docid
stringlengths
4
9
text
stringlengths
174
10k
title
stringlengths
2
300
25069745
OBJECTIVE To describe the epidemiology of urban malaria, an emerging problem in sub-Saharan Africa. METHOD Cross-sectional surveys of communities in Accra and Kumasi, Ghana, determining risk factors for malaria infection and anaemia in children aged 6-60 months. RESULTS Malaria prevalence rates ranged from 2% to 33% between urban communities. 47.1% of children were anaemic (Hb<11.0 g/dl). Factors associated with malaria prevalence were low socio-economic status, age and anaemia. The attributable risks of anaemia and severe anaemia (Hb<8.0 g/dl) caused by malaria were 5% and 23% respectively. CONCLUSIONS Malaria in urban areas displayed a heterogeneity and complexity that differed from the rural environment, which has important implications for malaria control. Marked intra-city variation indicates the importance of targeting specific areas or districts. The most vulnerable group, the urban poor, should be prioritized when designing control measures. This would require careful assessment of the malaria risk pattern in any city to guide an integrated control program.
Urban malaria and anaemia in children: a cross-sectional survey in two cities of Ghana.
25079962
CONTEXT Delayed cerebral vasospasm causes permanent neurological deficits or death in at least 15% of patients following otherwise successful treatment for ruptured intracranial aneurysm. Decreased bioavailability of nitric oxide has been associated with the development of cerebral vasospasm. OBJECTIVE To determine whether infusions of nitrite will prevent delayed cerebral vasospasm. DESIGN, SETTING, AND SUBJECTS A total of 14 anesthetized cynomolgus monkeys had an autologous blood clot placed around the right middle cerebral artery. Cerebral arteriography was performed before clot placement and on days 7 and 14 to assess vasospasm. The study was conducted from August 2003 to February 2004. INTERVENTIONS A 90-mg sodium nitrite intravenous solution infused over 24 hours plus a 45-mg sodium nitrite bolus daily (n = 3); a 180-mg sodium nitrite intravenous solution infused over 24 hours (n = 3); or a control saline solution infusion (n = 8). Each was infused continuously for 14 days. MAIN OUTCOME MEASURES Nitrite, S-nitrosothiol, and methemoglobin levels in blood and cerebrospinal fluid and degree of arteriographic vasospasm. RESULTS In control monkeys, mean (SD) cerebrospinal fluid nitrite levels decreased from 3.1 (1.5) micromol/L to 0.4 (0.1) micromol/L at day 7 and to 0.4 (0.4) micromol/L at day 14 (P = .03). All 8 control monkeys developed significant vasospasm of the right middle cerebral artery, which was complicated by stroke and death in 1 animal. Sodium nitrite infusions increased the nitrite and methemoglobin levels (<2.1% of total hemoglobin) in the blood and cerebrospinal fluid without evoking systemic hypotension. Nitrite infusion prevented development of vasospasm (no animals developed significant vasospasm; mean [SD] reduction in right middle cerebral artery area on day 7 after subarachnoid hemorrhage of 8% [9%] in nitrite-treated monkeys vs 47% [5%] in saline-treated controls; P<.001). There was a negative correlation between the concentration of nitrite in cerebrospinal fluid and the degree of cerebral vasospasm (P<.001). Pharmacological effects of nitrite infusion were also associated with the formation of S-nitrosothiol in cerebrospinal fluid. There was no clinical or pathological evidence of nitrite toxicity. CONCLUSION Subacute sodium nitrite infusions prevented delayed cerebral vasospasm in a primate model of subarachnoid hemorrhage.
Nitrite infusions to prevent delayed cerebral vasospasm in a primate model of subarachnoid hemorrhage.
25085979
Cells acquire their ultimate identities by activating combinations of transcription factors that initiate and sustain expression of the appropriate cell type-specific genes. T cell development depends on the progression of progenitor cells through three major phases, each of which is associated with distinct transcription factor ensembles that control the recruitment of these cells to the thymus, their proliferation, lineage commitment and responsiveness to T cell receptor signals, all before the allocation of cells to particular effector programmes. All three phases are essential for proper T cell development, as are the mechanisms that determine the boundaries between each phase. Cells that fail to shut off one set of regulators before the next gene network phase is activated are predisposed to leukaemic transformation.
Developmental gene networks: a triathlon on the course to T cell identity
25089501
Autosomal dominant polycystic kidney disease (ADPKD) is caused by heterozygous mutations in either PKD1 or PKD2, genes that encode polycystin-1 and polycystin-2, respectively. We show here that tumor necrosis factor-α (TNF-α), an inflammatory cytokine present in the cystic fluid of humans with ADPKD, disrupts the localization of polycystin-2 to the plasma membrane and primary cilia through a scaffold protein, FIP2, which is induced by TNF-α. Treatment of mouse embryonic kidney organ cultures with TNF-α resulted in formation of cysts, and this effect was exacerbated in the Pkd2+/− kidneys. TNF-α also stimulated cyst formation in vivo in Pkd2+/− mice. In contrast, treatment of Pkd2+/− mice with the TNF-α inhibitor etanercept prevented cyst formation. These data reveal a pathway connecting TNF-α signaling, polycystins and cystogenesis, the activation of which may reduce functional polycystin-2 below a critical threshold, precipitating the ADPKD cellular phenotype.
A tumor necrosis factor-α–mediated pathway promoting autosomal dominant polycystic kidney disease
25098790
Inefficient inhaler technique is a common problem resulting in poor drug delivery, decreased disease control and increased inhaler use. The aim of this study was to assess patients' use of different inhaler devices and to ascertain whether patient preference is indicative of ease of use and whether current inhaler use has any influence on either technique or preference. We also wished to define the most appropriate method of selecting an inhaler for a patient, taking into account observed technique and device cost. One hundred patients received instruction, in randomized order, in the use of seven different inhaler devices. After instruction they were graded (using predetermined criteria) in their inhaler technique. After assessment patients were asked which three inhalers they most preferred and which, if any, they currently used. Technique was best using the breath-actuated inhalers; the Easi-Breathe and Autohaler, with 91% seen to have good technique. The pressurized metered dose inhaler (pMDI) fared poorly, in last position with only 79% of patients showing good technique, despite being the most commonly prescribed. The Easi-Breathe was by far the most popular device with the patients. The Autohaler came in second position closely followed by the Clickhaler and Accuhaler. The majority of patients (55%) currently used the pMDI but the pMDI did not score highly for preference or achieve better grades than the other devices. Only 79% of patients tested could use the pMDI effectively even after expert instruction yet it continues to be commonly prescribed. This has important repercussions for drug delivery and hence disease control. Prescribing a patient's preferred device increases cost but can improve efficiency and therefore be cost effective in the long term. Using an inexpensive device (pMDI) when technique is good and the patient's preferred inhaler device when not is one way to optimize delivery and may even reduce cost.
Inappropriate inhaler use: assessment of use and patient preference of seven inhalation devices. EDICI.
25104843
We report on a patient treated with hemoperfusion-hemodialysis (HP-HD) for severe paraquat poisoning. This procedure was adopted since the combination of adsorption and dialysis may improve overall drug removal. On admission blood paraquat was 15.8 micrograms/ml. He received conventional treatment and combined HP-HD which started within 3 hours after ingestion of the chemical and lasted 5 hours. Blood samples were obtained during and after HP-HD. The samples during HP-HD were taken before the charcoal column, between the charcoal column and the artificial kidney and after the artificial kidney. Blood clearances of paraquat were 116 +/- 32 ml/min (n=6) for the charcoal column (HP), 90 +/- 54 ml/min (n=6) for the artificial kidney (HD) and 151 +/- 37 ml/min (n=6) for the combined systems (HP-HD). After HP-HD a limited rebound of blood paraquat level was seen. One day after admission renal and hepatic failure had developed, and the patient died after 5 days. Tissue paraquat levels (microgram/g wet tissue) were: skeletal muscle 9.4, pancreas 6.0, prostate 5.6, thyroid 4.2, lungs 4.0, bone marrow 4.0, kidney 3.1, spleen 2.9, adrenal 2.9, heart 2.8, liver 2.3, stomach and testis below 1.0. Measurements of blood levels demonstrated the efficient clearances of paraquat with HP-HD from the central (plasma) compartment. However, the present results confirmed those previously reported which suggest that the efficiency of short HP-HD in treating severe paraquat poisoning is questionable since paraquat levels in the peripheral (tissue) compartment remain elevated.
Hemoperfusion-hemodialysis ineffective for paraquat removal in life-threatening poisoning?
25121903
The number of cancer survivors continues to increase due to the aging and growth of the population and improvements in early detection and treatment. In order for the public health community to better serve these survivors, the American Cancer Society and the National Cancer Institute collaborated to estimate the number of current and future cancer survivors using data from the Surveillance, Epidemiology, and End Results (SEER) program registries. In addition, current treatment patterns for the most common cancer types are described based on information in the National Cancer Data Base and the SEER and SEER-Medicare linked databases; treatment-related side effects are also briefly described. Nearly 14.5 million Americans with a history of cancer were alive on January 1, 2014; by January 1, 2024, that number will increase to nearly 19 million. The 3 most common prevalent cancers among males are prostate cancer (43%), colorectal cancer (9%), and melanoma (8%), and those among females are cancers of the breast (41%), uterine corpus (8%), and colon and rectum (8%). The age distribution of survivors varies substantially by cancer type. For example, the majority of prostate cancer survivors (62%) are aged 70 years or older, whereas less than one-third (32%) of melanoma survivors are in this older age group. It is important for clinicians to understand the unique medical and psychosocial needs of cancer survivors and to proactively assess and manage these issues. There are a growing number of resources that can assist patients, caregivers, and health care providers in navigating the various phases of cancer survivorship.
Cancer treatment and survivorship statistics, 2014.
25124117
Archaeal viruses display unusually high genetic and morphological diversity. Studies of these viruses proved to be instrumental for the expansion of knowledge on viral diversity and evolution. The Sulfolobus islandicus rod-shaped virus 2 (SIRV2) is a model to study virus-host interactions in Archaea. It is a lytic virus that exploits a unique egress mechanism based on the formation of remarkable pyramidal structures on the host cell envelope. Using whole-transcriptome sequencing, we present here a global map defining host and viral gene expression during the infection cycle of SIRV2 in its hyperthermophilic host S. islandicus LAL14/1. This information was used, in combination with a yeast two-hybrid analysis of SIRV2 protein interactions, to advance current understanding of viral gene functions. As a consequence of SIRV2 infection, transcription of more than one-third of S. islandicus genes was differentially regulated. While expression of genes involved in cell division decreased, those genes playing a role in antiviral defense were activated on a large scale. Expression of genes belonging to toxin-antitoxin and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas systems was specifically pronounced. The observed different degree of activation of various CRISPR-Cas systems highlights the specialized functions they perform. The information on individual gene expression and activation of antiviral defense systems is expected to aid future studies aimed at detailed understanding of the functions and interplay of these systems in vivo.
Massive activation of archaeal defense genes during viral infection.
25134146
Hepatitis C virus (HCV) is frequently encountered in human immunodeficiency virus (HIV)-infected patients because of common routes of transmission. Previous studies suggested that HIV infection impaired the natural course of chronic hepatitis C, with a more rapid progression to cirrhosis. However, these studies did not assess the HIV infection impact on chronic hepatitis C by taking into account the risk factors for liver fibrosis progression: alcohol, sex, age at the contamination, and duration of HCV infection. We studied liver biopsy specimens of 2 groups of 58 patients that were infected by both HCV and HIV or by HCV alone. The 2 groups were matched according those risk factors, and liver biopsy responses were evaluated with the METAVIR items. The METAVIR activity was higher in HIV-positive than HIV-negative patients. Cirrhosis was more frequent: (1) in HIV-positive patients with CD4 < or = 200 cells/microL (45%) than in HIV-negative patients (10%) (P = .003), (2) in HIV-positive patients with CD4 < or = 200 cells/microL (45%) than in HIV-positive patients with CD4 > 200 cells/microL (17%) (P = .04). These differences, which were linked to HIV status, might be related to the enhanced HCV replication during HIV infection or other immune mechanisms that need further studies.
Impact of human immunodeficiency virus infection on the histological features of chronic hepatitis C: a case-control study. The MULTIVIRC group.
25135304
The purpose of this study was to examine the relation of leptin to metabolic and dietary factors in college-age adults. Young adult women and men (n = 32) were recruited and underwent testing for measurement of body mass index, body composition, peak oxygen consumption (VO2peak), dietary intake, and plasma levels of leptin and insulin. Ln leptin was significantly greater for women than for men (2.1 versus 1.2 ng/mL, respectively). This difference remained significant even after adjusting ln leptin for fat mass and fat-free mass as covariates in separate analyses. VO2peak was higher for men than for women and this remained significant after adjustment for differences in fat-free mass and total body mass. Significant correlations were found between ln leptin and indicators of fat mass in women and men, with higher correlations for similar variables observed in men (r = 0.548, 0.674, and 0.732 for body mass index, percentage of body fat, and fat mass [kg] for women, respectively, and r = 0.740, 0.888, 0.858 for body mass index, percentage of body fat, and fat mass [kg] for men, respectively). Ln leptin showed a significant inverse relationship with VO2peak (r = -0.751) in men only. After adjusting ln leptin for body fat mass using partial correlations, ln leptin was not significantly associated with any of the measured variables. Alternatively, after normalization of ln leptin using fat mass as the divisor, a less adequate statistical analysis method, men showed statistical significant correlations between ln leptin and dietary intake and VO2peak. Although plasma leptin values were higher in women, stronger associations were evident for men than for women between leptin and metabolic and dietary factors.
Relation of plasma leptin concentrations to sex, body fat, dietary intake, and peak oxygen uptake in young adult women and men.
25141908
The human cytomegalovirus UL111A region is active during both productive and latent phases of infection. During productive infection, the virus expresses ORF79, a protein with oncogenic properties, and cmvIL-10, a functional homolog of human IL-10. During latent infection of myeloid progenitor cells, an alternately spliced variant of cmvIL-10, termed latency-associated (LA) cmvIL-10 has previously been identified. To determine whether LAcmvIL-10 transcription occurs during productive infection, we performed 5' and 3' RACE to map UL111A-region transcripts in productively infected human foreskin fibroblasts (HFFs). This analysis revealed the presence of a singly spliced UL111A-region transcript predicted to encode LAcmvIL-10. This transcript was expressed in HFFs with early (beta) kinetics, a temporal class that differs from that of ORF79 (alpha kinetics) and cmvIL-10 (gamma kinetics). These data identify and map a transcript encoding a latency-associated homolog of IL-10 which is expressed by the virus during the productive phase of infection.
Expression of a human cytomegalovirus latency-associated homolog of interleukin-10 during the productive phase of infection.
25148216
Several members of the Kruppel-like factor (KLF) family of transcription factors play important roles in differentiation, survival, and trafficking of blood and immune cell types. We demonstrate in this study that hematopoietic cells from KLF4(-/-) fetal livers (FL) contained normal numbers of functional hematopoietic progenitor cells, were radioprotective, and performed as well as KLF4(+/+) cells in competitive repopulation assays. However, hematopoietic "KLF4(-/-) chimeras" generated by transplantation of KLF4(-/-) fetal livers cells into lethally irradiated wild-type mice completely lacked circulating inflammatory (CD115(+)Gr1(+)) monocytes, and had reduced numbers of resident (CD115(+)Gr1(-)) monocytes. Although the numbers and function of peritoneal macrophages were normal in KLF4(-/-) chimeras, bone marrow monocytic cells from KLF4(-/-) chimeras expressed lower levels of key trafficking molecules and were more apoptotic. Thus, our in vivo loss-of-function studies demonstrate that KLF4, previously shown to mediate proinflammatory signaling in human macrophages in vitro, is essential for differentiation of mouse inflammatory monocytes, and is involved in the differentiation of resident monocytes. In addition, inducible expression of KLF4 in the HL60 human acute myeloid leukemia cell line stimulated monocytic differentiation and enhanced 12-O-tetradecanoylphorbol 13-acetate induced macrophage differentiation, but blocked all-trans-retinoic acid induced granulocytic differentiation of HL60 cells. The inflammation-selective effects of loss-of-KLF4 and the gain-of-KLF4-induced monocytic differentiation in HL60 cells identify KLF4 as a key regulator of monocytic differentiation and a potential target for translational immune modulation.
Kruppel-like factor 4 is essential for inflammatory monocyte differentiation in vivo.
25157790
This study investigated the association between green tea consumption and leukemia. A total of 252 cases (90.3% response) and 637 controls (53.4% response) were enrolled. Controls were matched for cases on age and gender. Information was collected on participants’ living habits, including tea consumption. Green tea was used as a standard to estimate the total amount of individual catechin consumption. We stratified individual consumption of catechins into four levels. Conditional logistic regression models were fit to subjects aged 0–15 and 16–29 years to evaluate separate associations between leukemia and catechin consumption. A significant inverse association between green tea consumption and leukemia risk was found in individuals aged 16–29 years, whereas no significant association was found in the younger age groups. For the older group with higher amounts of tea consumption (>550 units of catechins), the adjusted odds ratio (OR) compared with the group without tea consumption was 0.47 [95% confidence interval (CI) = 0.23–0.97]. After we adjusted for smoking status and medical irradiation exposure, the overall OR for all participants was 0.49 (95% CI = 0.27–0.91), indicating an inverse relation between large amounts of catechins and leukemia. Drinking sufficient amounts of tea, especially green tea, which contains more catechins than oolong tea and black tea, may reduce the risk of leukemia.
A population-based, case–control study of green tea consumption and leukemia risk in southwestern Taiwan
25175223
RNA polymerase II is implicated in the RNA-templated RNA synthesis during replication of viroids and Hepatitis Delta Virus (HDV); however, neither the RNA template nor protein factor requirements for this process are well defined. We have developed an in vitro transcription system based on HeLa cell nuclear extract (NE), in which a segment of antigenomic RNA corresponding to the left-hand tip region of the HDV rod-like structure serves as a template for efficient and highly specific RNA synthesis. Accumulation of the unique RNA product is highly sensitive to alpha-amanitin in HeLa NE and only partially sensitive to this drug in NE from PMG cells that contain an allele of the alpha-amanitin-resistant subunit of pol II, strongly suggesting pol II involvement in this reaction. Detailed analysis of the RNA product revealed that it represents a chimeric molecule composed of a newly synthesized transcript covalently attached to the 5' half of the RNA template. Selection of the start site for transcription is remarkably specific and depends on the secondary structure of the RNA template, rather than on its primary sequence. Some features of this reaction resemble the RNA cleavage-extension process observed for pol II-arrested complexes in vitro. A possible involvement of the described reaction in HDV replication is discussed.
Specific HDV RNA-templated transcription by pol II in vitro.
25175997
In patients presenting with idiopathic pulmonary fibrosis (IPF), modifications of pulmonary vessels are well defined in fibrotic areas but have not been accurately assessed in the intervening patches of preserved lung. Moreover, the relation between pulmonary vessel lesions and pulmonary hemodynamics is not well known. We therefore designed a retrospective study on lung explant specimens from 26 patients with a firm diagnosis of IPF who had undergone lung transplantation. Our aim was to (1) describe the vascular lesions, especially in preserved lung areas, and (2) correlate them with pulmonary hemodynamics. In dense fibrotic zones, thickening of the arterial and venous wall with severe luminal narrowing was present in each patient. In architecturally preserved lung zones, occlusion of venules and small pulmonary veins was observed in 65% of the patients, although there were only mild changes of muscular pulmonary arteries. We found a significant positive correlation between the macroscopic extent of lung fibrosis and mean pulmonary artery pressure, but we failed to find a relation between mean pulmonary artery pressure and venous/venular lesions in nonfibrotic areas. Our study points out that in many patients with IPF, nonfibrotic lung areas demonstrate an occlusive venopathy, the signification of which remains undetermined.
Pulmonary vascular lesions in end-stage idiopathic pulmonary fibrosis: Histopathologic study on lung explant specimens and correlations with pulmonary hemodynamics.
25182647
Acute fatty liver of pregnancy (AFLP) and the syndrome of hemolysis, elevated liver enzyme levels, and low platelet count (HELLP) are rare but major disorders of the third trimester of pregnancy. Over a 10-year period, 46 women (median age, 30 years; range, 17-41 years) developed hepatic dysfunction severe enough to require transfer to our Liver Failure Unit. Three quarters of the women were nulliparous, and 5 had twin pregnancies; the median gestational age was 35 weeks (range, 24-40 weeks). At admission, 32 patients (70%) were preeclamptic and 21 (46%) were encephalopathic and/or ventilated. Thirty-two patients (70%) had clinical features and laboratory values consistent with AFLP, and 7 (15%) had HELLP syndrome. One patient had preeclamptic liver rupture requiring liver transplantation. In 6 other patients, causes of severe liver dysfunction unrelated to pregnancy were found. Infectious complications occurred in 17 of the patients with AFLP (53%) and in 2 of those with HELLP syndrome (29%). Major intra-abdominal bleeding occurred in 12 women (10 with AFLP), 9 of whom required laparotomies for clot evacuation. Four patients with AFLP (12.5%) had a fatal outcome, with a corresponding perinatal mortality rate of 9%. There were no maternal or perinatal deaths associated with HELLP syndrome. In contrast to results of many previous studies, the results of this large series suggest a relatively favorable maternal and perinatal outcome in severe AFLP and HELLP syndrome. Further improvements in outcome are likely to be achieved through the prevention of the bleeding and infectious complications associated with these disorders.
Maternal and perinatal outcome in severe pregnancy-related liver disease.
25183830
Circadian oscillators play an indispensable role in the coordination of physiological processes with the cyclic changes in the physical environment. A significant number of recent clinical and molecular studies suggest that circadian biology may play an important role in the regulation of adipose and other metabolic tissue functions. In this discussion, we present the hypothesis that circadian dysfunction may be involved in the pathogenesis of obesity, type 2 diabetes, and the metabolic syndrome.
Circadian rhythms and the regulation of metabolic tissue function and energy homeostasis.
25186412
The PANTHER (protein annotation through evolutionary relationship) classification system (http://www.pantherdb.org/) is a comprehensive system that combines gene function, ontology, pathways and statistical analysis tools that enable biologists to analyze large-scale, genome-wide data from sequencing, proteomics or gene expression experiments. The system is built with 82 complete genomes organized into gene families and subfamilies, and their evolutionary relationships are captured in phylogenetic trees, multiple sequence alignments and statistical models (hidden Markov models or HMMs). Genes are classified according to their function in several different ways: families and subfamilies are annotated with ontology terms (Gene Ontology (GO) and PANTHER protein class), and sequences are assigned to PANTHER pathways. The PANTHER website includes a suite of tools that enable users to browse and query gene functions, and to analyze large-scale experimental data with a number of statistical tests. It is widely used by bench scientists, bioinformaticians, computer scientists and systems biologists. In the 2013 release of PANTHER (v.8.0), in addition to an update of the data content, we redesigned the website interface to improve both user experience and the system's analytical capability. This protocol provides a detailed description of how to analyze genome-wide experimental data with the PANTHER classification system.
Large-scale gene function analysis with the PANTHER classification system
25191216
Fibrous dysplasia is a benign bone disease caused by a mutation in the gene for the stimulatory guanine nucleotide-binding protein Gs alpha, leading to high cyclic adenosine monophosphate levels. Histologically, fibrous dysplasia is characterized by the production of fibrous tissue accompanied by the deposition of ectopic type I collagen and other bone-associated extracellular matrix proteins, as well as by irregular woven intramembranous bone onto which type I collagen-containing Sharpey fibers are often attached. Fibrous dysplasia is also characterized by high expression of c-Fos/c-Jun, known targets for cyclic adenosine monophosphate signaling. In this study, we examined the expression of the bone-related extracellular matrix protein, periostin, and its known receptor, integrin alpha v beta 3 (CD51/61), in normal bones as well as in fibrous dysplasia. Immunohistochemistry and in situ hybridization studies revealed that periostin was expressed in the extracellular matrix during intramembranous but not endochondral ossification, as well as in the fibrous component of fibrous dysplasia; and all cells adjacent to periostin-positive regions expressed CD51/61. Importantly, periostin was abundantly localized to Sharpey fibers. To investigate the contribution of c-Fos, we examined transgenic mice overexpressing c-fos, which develop sclerotic lesions closely resembling those found in fibrous dysplasia. In all lesions, transformed osteoblasts expressed high levels of periostin, whereas normal osteoblasts did not. Our results show that periostin is a novel marker for intramembranous ossification, and is a good candidate as a diagnostic tool and/or a therapeutic target in fibrous dysplasia. Moreover, the Gs alpha-cyclic adenosine monophosphate-c-Fos pathway might represent one mechanism of periostin up-regulation in fibrous dysplasia, resulting in altered collagen fibrillogenesis characteristic of this disease.
Periostin, a novel marker of intramembranous ossification, is expressed in fibrous dysplasia and in c-Fos-overexpressing bone lesions.
25238950
Fibroblast growth factors (FGFs) have mitogenic activity toward a wide variety of cells of mesenchymal, neuronal, and epithelial origin and regulate events in normal embryonic development, angiogenesis, wound repair, and neoplasia. FGF-2 is expressed in many normal adult tissues and can regulate migration and replication of intestinal epithelial cells in culture. However, little is known about the effects of FGF-2 on intestinal epithelial stem cells during either normal epithelial renewal or regeneration of a functional epithelium after injury. In this study, we investigated the expression of FGF-2 in the mouse small intestine after irradiation and determined the effect of exogenous FGF-2 on crypt stem cell survival after radiation injury. Expression of FGF-2 mRNA and protein began to increase at 12 h after gamma-irradiation, and peak levels were observed from 48 to 120 h after irradiation. At all times after irradiation, the higher molecular mass isoform ( approximately 24 kDa) of FGF-2 was the predominant form expressed in the small intestine. Immunohistochemical analysis of FGF-2 expression after radiation injury demonstrated that FGF-2 was predominantly found in the mesenchyme surrounding regenerating crypts. Exogenous recombinant human FGF-2 (rhFGF-2) markedly enhanced crypt stem cell survival when given before irradiation. We conclude that expression of FGF-2 is induced by radiation injury and that rhFGF-2 can enhance crypt stem cell survival after subsequent injury.
FGF-2 enhances intestinal stem cell survival and its expression is induced after radiation injury.
25251625
The use of caspase inhibitors has revealed the existence of alternative backup cell death programs for apoptosis. The broad-spectrum caspase inhibitor zVAD-fmk modulates the three major types of cell death. Addition of zVAD-fmk blocks apoptotic cell death, sensitizes cells to necrotic cell death, and induces autophagic cell death. Several studies have shown a crucial role for the kinase RIP1 and the adenosine nucleotide translocator (ANT)-cyclophilin D (CypD) complex in necrotic cell death. The underlying mechanism of zVAD-fmk-mediated sensitization to necrotic cell death involves the inhibition of caspase-8-mediated proteolysis of RIP1 and disturbance of the ANT-CypD interaction. RIP1 is also involved in autophagic cell death. Caspase inhibitors and knockdown studies have revealed negative roles for catalase and caspase-8 in autophagic cell death. The positive role of RIP1 and the negative role of caspase-8 in both necrotic and autophagic cell death suggest that the pathways of these two types of cell death are interconnected. Necrotic cell death represents a rapid cellular response involving mitochondrial reactive oxygen species (ROS) production, decreased adenosine triphosphate concentration, and other cellular insults, whereas autophagic cell death first starts as a survival attempt by cleaning up ROS-damaged mitochondria. However, when this process occurs in excess, autophagy itself becomes cytotoxic and eventually leads to autophagic cell death. A better understanding of the molecular mechanisms of these alternative cell death pathways may provide therapeutic tools to combat cell death associated with neurodegenerative diseases, ischemia-reperfusion pathologies, and infectious diseases, and may also facilitate the development of alternative cytotoxic strategies in cancer treatment.
Caspase inhibitors promote alternative cell death pathways.
25254425
Nucleosomes containing the histone variant H3.3 tend to be clustered in vivo in the neighborhood of transcriptionally active genes and over regulatory elements. It has not been clear, however, whether H3.3-containing nucleosomes possess unique properties that would affect transcription. We report here that H3.3 nucleosomes isolated from vertebrates, regardless of whether they are partnered with H2A or H2A.Z, are unusually sensitive to salt-dependent disruption, losing H2A/H2B or H2A.Z/H2B dimers. Immunoprecipitation studies of nucleosome core particles (NCPs) show that NCPs that contain both H3.3 and H2A.Z are even less stable than NCPs containing H3.3 and H2A. Intriguingly, NCPs containing H3 and H2A.Z are at least as stable as H3/H2A NCPs. These results establish an hierarchy of stabilities for native nucleosomes carrying different complements of variants, and suggest how H2A.Z could play different roles depending on its partners within the NCP. They also are consistent with the idea that H3.3 plays an active role in maintaining accessible chromatin structures in enhancer regions and transcribed regions. Consistent with this idea, promoters and enhancers at transcriptionally active genes and coding regions at highly expressed genes have nucleosomes that simultaneously carry both H3.3 and H2A.Z, and should therefore be extremely sensitive to disruption.
Nucleosome stability mediated by histone variants H3.3 and H2A.Z.
25259746
We evaluated oral 1,25-vitamin D3 for as long as 26 months in six prepubescent children with renal osteodystrophy previously treated with vitamin D2. Therapy was given at 14 to 41 ng per kilogram per day to correct hypocalcemia and reverse bone disease. Serum levels of 1,25-vitamin D3 were initially reduced at 15 +/- 5 pg per milliliter (mean +/- S.E.M.) and after treatment rose to 54 +/- 13. Serum calcium rose from 7.5 +/- 1.6 mg per deciliter (mean +/- S.D.) to 9.8 +/- 0.6 after one month (P less than 0.02). Alkaline phosphatase activity fell from 536 +/- 298 to 208 +/- 91 IU per liter after 12 months (P less than 0.05). Serum immunoreactive parathyroid levels fell from 900 +/- 562 microliter eq per milliliter 411 +/- 377. Healing of rickets and subperiosteal erosions was found. Remineralization of bone was demonstrated by the photon absorption technic. In four patients growth velocity, evaluated for 12 months before and after therapy, increased from 2.6 +/- 0.8 to 8.0 +/- 3.2 cm per year. Growth velocity per year increased from less than third percentile in each to the 10th to 97th percentile after therapy. Height increment ranged from 27 to 113 per cent of that expected for change in chronologic age and 40 to 114 per cent expected for change in bone age after therapy. This trial demonstrates that oral 1,25-vitamin D3 can reverse renal bone disease and increase growth in uremic children.
Increased growth after long-term oral 1alpha,25-vitamin D3 in childhood renal osteodystrophy.
25261168
OBJECTIVES To assess the association between severity of neuropathy and disease stage, and estimate the rate of neuropathy progression in a retrospective cross-sectional analysis of a multinational population of patients with familial amyloidotic polyneuropathy (FAP). METHODS We characterize neuropathy severity and rate of progression in available patients with FAP in France, the United States, Portugal, and Italy. Neuropathy Impairment Scores (NIS), time from symptom onset to NIS measurement, polyneuropathy disability (PND) scores, FAP disease stage, and manual grip strength data were collected. We estimated neuropathy progression using Loess Fit and Gompertz Fit models. RESULTS For the 283 patients studied (mean age, 56.4 years), intercountry genotypic variation in the transthyretin (TTR) mutation was observed, with the majority of patients in Portugal (92%) having early-onset Val30Met-FAP. There was also marked intercountry variation in PND score, FAP stage, and TTR stabilizer use. NIS was associated with PND score (NIS 10 and 99 for scores I and IV, respectively; p < 0.0001) and FAP stage (NIS 14 and 99 for stages 1 and 3, respectively; p < 0.0001). In addition, there was an association between NIS and TTR genotype. The estimated rate of NIS progression for a population with a median NIS of 32 was 14.3 points/year; the corresponding estimated rate for the modified NIS+7 is 17.8 points/year. CONCLUSIONS In a multinational population of patients with FAP, rapid neuropathic progression is observed and the severity of neuropathy is associated with functional scales of locomotion.
Rapid progression of familial amyloidotic polyneuropathy: a multinational natural history study.
25263810
The switch from the latent to the lytic form of Epstein-Barr virus (EBV) infection is mediated by expression of the viral immediate-early (IE) proteins, BZLF1 (Z) and BRLF1 (R). An EBV early protein, BRRF1 (Na), is encoded by the opposite strand of the BRLF1 intron, but the function of this nuclear protein in the viral life cycle is unknown. Here we demonstrate that Na enhances the R-mediated induction of lytic EBV infection in 293 cells latently infected with a recombinant EBV (R-KO) defective for the expression of both R and Na. Na also enhances R-induced lytic infections in a gastric carcinoma line (AGS) carrying the R-KO virus, although it has no effect in a Burkitt lymphoma line (BL-30) stably infected with the same mutant virus. We show that Na is a transcription factor that increases the ability of R to activate Z expression from the R-KO viral genome in 293 cells and that Na by itself activates the Z promoter (Zp) in EBV-negative cells. Na activation of Zp requires a CRE motif (ZII), and a consensus CRE motif is sufficient to transfer Na responsiveness to the heterologous E1b promoter. Furthermore, we show that Na enhances the transactivator function of a Gal4-c-Jun fusion protein but does not increase the transactivator function of other transcription factors (including ATF-1, ATF-2, and CREB) known to bind CRE motifs. Na expression in cells results in increased levels of a hyperphosphorylated form of c-Jun, suggesting a mechanism by which Na activates c-Jun. Our results indicate that Na is a transcription factor that activates the EBV Zp IE promoter through its effects on c-Jun and suggest that Na cooperates with BRLF1 to induce the lytic form of EBV infection in certain cell types.
The BRRF1 early gene of Epstein-Barr virus encodes a transcription factor that enhances induction of lytic infection by BRLF1.
25263942
Endometrial polyps are very common benign endometrial lesions, but their pathogenesis is poorly understood, except for a few studies indicating the possibility of benign stromal neoplasm. Although the histopathological diagnosis of endometrial polyp on a surgical specimen is straightforward, it is often difficult to differentiate endometrial polyp from endometrial hyperplasia on a biopsy or curettage specimen. Presently, there is no immunohistochemical marker helpful in this differential diagnosis. In this study, we examined p16 expression in 35 endometrial polyps and 33 cases of endometrial hyperplasia that included 16 simple hyperplasias, 14 complex atypical hyperplasias, and 3 complex hyperplasias without atypia. Stromal p16 expression differed significantly between the two groups; it was seen in 31 (89 %) endometrial polyps, but in only 1 (3 %) endometrial hyperplasia. The percentage of p16-positive stromal cells ranged from 10 to 90 % (mean, 47 %) and the positive cells tended to be distributed around glands. Six cases of endometrial hyperplasia within an endometrial polyp were also examined and all cases showed stromal p16 expression. There was no difference in glandular p16 expression between endometrial polyps 33 (94 %) and hyperplasia 27 (82 %). The p16-immunoreactivity was mostly confined to metaplastic epithelial cells in both groups. Stromal p16 expression might be a peculiar characteristic of endometrial polyp and constitute a useful marker for the diagnosis, especially in fragmented specimens from biopsy or curettage. Stromal p16 expression might be a reflection of p16-induced cellular senescence, which has been documented in several benign mesenchymal neoplasms.
Stromal p16 expression differentiates endometrial polyp from endometrial hyperplasia
25293616
CONTEXT Despite improvements in mental health services in recent decades, it is unclear whether the risk of mortality in schizophrenia has changed over time. OBJECTIVE To explore the distribution of standardized mortality ratios (SMRs) for people with schizophrenia. DATA SOURCES Broad search terms were used in MEDLINE, PsychINFO, Web of Science, and Google Scholar to identify all studies that investigated mortality in schizophrenia, published between January 1, 1980, and January 31, 2006. References were also identified from review articles, reference lists, and communication with authors. STUDY SELECTION Population-based studies that reported primary data on deaths in people with schizophrenia. DATA EXTRACTION Operationalized criteria were used to extract key study features and mortality data. DATA SYNTHESIS We examined the distribution of SMRs and pooled selected estimates using random-effects meta-analysis. We identified 37 articles drawn from 25 different nations. The median SMR for all persons for all-cause mortality was 2.58 (10%-90% quantile, 1.18-5.76), with a corresponding random-effects pooled SMR of 2.50 (95% confidence interval, 2.18-2.43). No sex difference was detected. Suicide was associated with the highest SMR (12.86); however, most of the major causes-of-death categories were found to be elevated in people with schizophrenia. The SMRs for all-cause mortality have increased during recent decades (P = .03). CONCLUSIONS With respect to mortality, a substantial gap exists between the health of people with schizophrenia and the general community. This differential mortality gap has worsened in recent decades. In light of the potential for second-generation antipsychotic medications to further adversely influence mortality rates in the decades to come, optimizing the general health of people with schizophrenia warrants urgent attention.
A systematic review of mortality in schizophrenia: is the differential mortality gap worsening over time?
25293721
Placental oxidative stress plays a key role in the pathophysiology of placenta-related disorders, most notably preeclampsia (PE) and intrauterine growth restriction (IUGR). Oxidative stress occurs when accumulation of reactive oxygen species (ROS) damages DNA, proteins and lipids, an outcome that is limited by antioxidant enzymes; mitochondrial uncoupling protein 2 (UCP2) may also limit oxidative stress by reducing ROS production. Here we characterized placental antioxidant defenses during normal gestation and following glucocorticoid-induced IUGR. Placentas were collected on Days 16 and 22 of normal rat pregnancy (term = Day 23) and at Day 22 after dexamethasone treatment from Day 13. Expression of several genes encoding antioxidant enzymes (Sod1, Sod2, Sod3, Cat, Gpx3, Txn1, Txnrd1, Txnrd2, and Txnrd3) and Ucp2 was measured by quantitative RT-PCR in the labyrinth (LZ) and junctional zones (JZ) of the placenta. Expression of Sod1 and Ucp2 mRNAs and the activity of xanthine oxidase, a source of ROS, all increased from Days 16 to 22 in both placental zones, whereas Sod2 and Gpx3 increased only in the rapidly growing LZ. In contrast, Sod3 and Txnrd1 expression fell in the LZ over this period, whereas total superoxide dismutase activity remained stable. Dexamethasone treatment reduced fetal-placental growth and LZ expression of Ucp2 but increased JZ expression of Txn1. Indices of placental oxidative damage (TBARS, F2-isoprostanes, and 8-OHdG) did not change with gestational age or dexamethasone, indicative of adequate antioxidant protection. Overall, our data suggest that the rat placenta is protected from oxidative stress by the dynamic zone- and stage-dependent expression of antioxidant defense genes.
Antioxidant Defenses in the Rat Placenta in Late Gestation: Increased Labyrinthine Expression of Superoxide Dismutases, Glutathione Peroxidase 3, and Uncoupling Protein 21
25298276
Bisphosphonates are currently used for the treatment of bone metastases, and emerging data suggest that they may also have antitumor properties. Preclinical studies have demonstrated that zoledronic acid can inhibit angiogenesis, invasion and adhesion of tumor cells, and overall tumor progression, and emerging evidence suggests that the use of these agents may impede the development of skeletal metastases. In a recent clinical study in patients with metastatic bone disease, basal levels of vascular endothelial growth factor, a factor essential for angiogenesis, were significantly reduced in patients receiving zoledronic acid, suggesting that zoledronic acid may have clinically relevant antiangiogenic properties. Early clinical data on prevention of bone metastases by the early-generation bisphosphonate clodronate have yielded promising results in patients with breast cancer, and trials are currently ongoing to assess the efficacy of clodronate in this setting. Similarly, the new-generation bisphosphonate zoledronic acid has demonstrated activity in the prevention of bone metastases in small, 18-month pilot studies in patients with high-risk solid tumors (N=40; P=0.0002). Similarly, in a separate 5-year trial, the overall survival of patients with multiple myeloma was greater in patients whose standard treatment regimens included zoledronic acid compared with standard treatment alone (P<0.01). These encouraging early clinical results supported the initiation of larger randomized trials that are currently ongoing.
Emerging role of bisphosphonates in the clinic--antitumor activity and prevention of metastasis to bone.
25300426
Murine ES cells can be maintained as a pluripotent, self-renewing population by LIF/STAT3-dependent signaling. The downstream effectors of this pathway have not been previously defined. In this report, we identify a key target of the LIF self-renewal pathway by showing that STAT3 directly regulates the expression of the Myc transcription factor. Murine ES cells express elevated levels of Myc and following LIF withdrawal, Myc mRNA levels collapse and Myc protein becomes phosphorylated on threonine 58 (T58), triggering its GSK3beta dependent degradation. Maintained expression of stable Myc (T58A) renders self-renewal and maintenance of pluripotency independent of LIF. By contrast, expression of a dominant negative form of Myc antagonizes self-renewal and promotes differentiation. Transcriptional control by STAT3 and suppression of T58 phosphorylation are crucial for regulation of Myc activity in ES cells and therefore in promoting self-renewal. Together, our results establish a mechanism for how LIF and STAT3 regulate ES cell self-renewal and pluripotency.
LIF/STAT3 controls ES cell self-renewal and pluripotency by a Myc-dependent mechanism.
25300664
Cardiovascular mortality is 10 to 20 times increased in patients with chronic renal failure (CRF). Risk factors for atherosclerosis are abundant in patients with CRF. However, the pathogenesis of cardiovascular disease in CRF remains to be elucidated. The effect of CRF on the development of atherosclerosis in apolipoprotein E-deficient male mice was examined. Seven-week-old mice underwent 5/6 nephrectomy (CRF, n = 28), unilateral nephrectomy (UNX, n = 24), or no surgery (n = 23). Twenty-two weeks later, CRF mice showed increased aortic plaque area fraction (0.266 +/- 0.033 versus 0.045 +/- 0.006; P < 0.001), aortic cholesterol content (535 +/- 62 versus 100 +/- 9 nmol/cm(2) intimal surface area; P < 0.001), and aortic root plaque area (205,296 +/- 22,098 versus 143,662 +/- 13,302 micro m(2); P < 0.05) as compared with no-surgery mice; UNX mice showed intermediate values. The plaques from uremic mice contained CD11b-positive macrophages and showed strong staining for nitrotyrosine. Systolic BP and plasma homocysteine concentrations were similar in uremic and nonuremic mice. Plasma urea and cholesterol concentrations were elevated 2.6-fold (P < 0.001) and 1.5-fold (P < 0.001) in CRF compared with no-surgery mice. Both variables correlated with aortic plaque area fraction (r(2) = 0.5, P < 0.001 and r(2) = 0.3, P < 0.001, respectively) and with each other (r(2) = 0.5, P < 0.001). On multiple linear regression analysis, only plasma urea was a significant predictor of aortic plaque area fraction. In conclusion, the present findings suggest that uremia markedly accelerates atherogenesis in apolipoprotein E-deficient mice. This effect could not be fully explained by changes in BP, plasma homocysteine levels, or total plasma cholesterol concentrations. Thus, the CRF apolipoprotein E-deficient mouse is a new model for studying the pathogenesis of accelerated atherosclerosis in uremia.
Chronic renal failure accelerates atherogenesis in apolipoprotein E-deficient mice.
25301182
CONTEXT Limited information exists regarding the role of left ventricular function in predicting exercise capacity and impact on age- and sex-related differences. OBJECTIVES To determine the impact of measures of cardiac function assessed by echocardiography on exercise capacity and to determine if these associations are modified by sex or advancing age. DESIGN Cross-sectional study of patients undergoing exercise echocardiography with routine measurements of left ventricular systolic and diastolic function by 2-dimensional and Doppler techniques. Analyses were conducted to determine the strongest correlates of exercise capacity and the age and sex interactions of these variables with exercise capacity. SETTING Large tertiary referral center in Rochester, Minnesota, in 2006. PARTICIPANTS Patients undergoing exercise echocardiography using the Bruce protocol (N = 2867). Patients with echocardiographic evidence of exercise-induced ischemia, ejection fractions lower than 50%, or significant valvular heart disease were excluded. MAIN OUTCOME MEASURE Exercise capacity in metabolic equivalents (METs). RESULTS Diastolic dysfunction was strongly and inversely associated with exercise capacity. Compared with normal function, after multivariate adjustment, those with moderate/severe resting diastolic dysfunction (-1.30 METs; 95% confidence interval [CI], -1.52 to -0.99; P < .001) and mild resting diastolic dysfunction (-0.70 METs; 95% CI, -0.88 to -0.46; P < .001) had substantially lower exercise capacity. Variation of left ventricular systolic function within the normal range was not associated with exercise capacity. Left ventricular filling pressures measured by resting E/e' of 15 or greater (-0.41 METs; 95% CI, -0.70 to -0.11; P = .007) or postexercise E/e' of 15 or greater (-0.41 METs; 95% CI, -0.71 to -0.11; P = .007) were similarly associated with a reduction in exercise capacity, each in separate multivariate analyses. Individuals with impaired relaxation (mild dysfunction) or resting E/e' of 15 or greater had a progressive increase in the magnitude of reduction in exercise capacity with advancing age (P < .001 and P = .02, respectively). Other independent correlates of exercise capacity were age (unstandardized beta coefficient, -0.85 METs; 95% CI, -0.92 to -0.77, per 10-year increment; P < .001), female sex (-1.98 METs; 95% CI, -2.15 to -1.84; P < .001), and body mass index greater than 30 (-1.24 METs; 95% CI, -1.41 to -1.10; P < .001). CONCLUSION In this large cross-sectional study of those referred for exercise echocardiography and not limited by ischemia, abnormalities of left ventricular diastolic function were independently associated with exercise capacity.
Left ventricular function and exercise capacity.
25308734
A dynamic population model of Ixodes scapularis, the vector of a number of tick-borne zoonoses in North America, was developed to simulate effects of temperature on tick survival and seasonality. Tick development rates were modelled as temperature-dependent time delays, calculated using mean monthly normal temperature data from specific meteorological stations. Temperature also influenced host-finding success in the model. Using data from stations near endemic populations of I. scapularis, the model reached repeatable, stable, cyclical equilibria with seasonal activity of different instars being very close to that observed in the field. In simulations run using data from meteorological stations in central and eastern Canada, the maximum equilibrium numbers of ticks declined the further north was the station location, and simulated populations died out at more northerly stations. Tick die-out at northern latitudes was due to a steady increase in mortality of all life stages with decreasing temperature rather than a specific threshold event in phenology of one life stage. By linear regression we investigated mean annual numbers of degree-days >0 degrees C (DD>0 degrees C) as a readily mapped index of the temperature conditions at the meteorological stations providing temperature data for the model. Maximum numbers of ticks at equilibrium were strongly associated with the mean DD>0 degrees C (r2>0.96, P<0.001), when the Province of origin of the meteorological station was accounted for (Quebec>Ontario, beta=103, P<0.001). The intercepts of the regression models provided theoretical limits for the establishment of I. scapularis in Canada. Maps of these limits suggested that the range of southeast Canada where temperature conditions are currently suitable for the tick, is much wider than the existing distribution of I. scapularis, implying that there is potential for spread. Future applications of the model in investigating climate change effects on I. scapularis are discussed.
A dynamic population model to investigate effects of climate on geographic range and seasonality of the tick Ixodes scapularis.
25315295
Mounting evidence indicates that inflammatory cytokines contribute to the development of depression in both medically ill and medically healthy individuals. Cytokines are important for development and normal brain function, and have the ability to influence neurocircuitry and neurotransmitter systems to produce behavioral alterations. Acutely, inflammatory cytokine administration or activation of the innate immune system produces adaptive behavioral responses that promote conservation of energy to combat infection or recovery from injury. However, chronic exposure to elevated inflammatory cytokines and persistent alterations in neurotransmitter systems can lead to neuropsychiatric disorders and depression. Mechanisms of cytokine behavioral effects involve activation of inflammatory signaling pathways in the brain that results in changes in monoamine, glutamate, and neuropeptide systems, and decreases in growth factors, such as brain-derived neurotrophic factor. Furthermore, inflammatory cytokines may serve as mediators of both environmental (e.g. childhood trauma, obesity, stress, and poor sleep) and genetic (functional gene polymorphisms) factors that contribute to depression's development. This review explores the idea that specific gene polymorphisms and neurotransmitter systems can confer protection from or vulnerability to specific symptom dimensions of cytokine-related depression. Additionally, potential therapeutic strategies that target inflammatory cytokine signaling or the consequences of cytokines on neurotransmitter systems in the brain to prevent or reverse cytokine effects on behavior are discussed.
Inflammatory cytokines in depression: neurobiological mechanisms and therapeutic implications.
25319221
INTRODUCTION The GOLD guidelines advocate not to institute inhaled corticosteroids (ICS) in patients with mild-to-moderate COPD. However, many patients do use ICS and in some patients, withdrawal is associated with deteriorating lung function and increased exacerbation rates. Unfortunately, physicians do not know in which patients they can stop ICS treatment safely. AIM To identify predictors of COPD exacerbations after ICS withdrawal. METHODS During ICS treatment, post-bronchodilator spirometry, body plethysmography, and health status assessment were performed in 68 COPD patients using ICS. Additionally, sputum cell differentials, supernatant leukotriene B(4), eosinophilic cationic protein, and myeloperoxidase, serum C-reactive protein and soluble intracellular adhesion molecule, and urinary desmosine were assessed. Sputum was also analysed for mRNA levels of haemoxygenase-1, tumour necrosis factor-α, RANTES, interleukin 5(IL-5), IL-10, IL-12, IL-13, transforming growth factor-β, and interferon-γ. STATISTICS Cox regression analyses were performed using time to exacerbation as outcome variable to identify significant hazards for a COPD exacerbation after ICS withdrawal. RESULTS Higher sputum % eosinophils, higher sputum MPO/neutrophil level, longer duration of COPD symptoms, <40 packyears smoking, and ICS withdrawal in November, December or January were significant hazards (all p<0.05) for experiencing a COPD exacerbation after ICS withdrawal in a monovariate model. In a multivariate model, all factors proved independent predictors except for sputum MPO/neutrophil level. CONCLUSIONS Decisions on whether or not inhaled corticosteroids can be safely withdrawn in mild-to-moderate COPD can be facilitated by assessment of sputum inflammation, particularly eosinophil numbers, next to packyears smoking, season, and duration of COPD symptoms.
Sputum inflammation predicts exacerbations after cessation of inhaled corticosteroids in COPD.
25328476
PURPOSE Peroxisome proliferator-activated receptors (PPAR) regulate lipid and glucose metabolism but their anticancer properties have been recently studied as well. We previously reported the antimetastatic activity of the PPARalpha ligand, fenofibrate, against melanoma tumors in vivo. Here we investigated possible molecular mechanisms of fenofibrate anti metastatic action. EXPERIMENTAL DESIGN Monolayer cultures of mouse (B16F10) and human (SkMell88) melanoma cell lines, soft agar assay, and cell migration assay were used in this study. In addition, we analyzed PPARalpha expression and its transcriptional activity in response to fenotibrate by using Western blots and liciferase-based reporter system. RESULTS Fenofibrate inhibited migration of B16F10 and SkMel188 cells in Transwell chambers and colony formation in soft agar. These effects were reversed by PPAR inhibitor, GW9662. Western blot analysis revealed time-dependent down-regulation of Akt and extracellular signal-regulated kinase l/2 phosphorylation in fenofibrate-treated cells. A B16F10 cell line stably expressing constitutively active Akt mutant was resistant to fenofibrate. In contrast, Akt gene silencing with siRNA mimicked the fenofibrate action and reduced the migratory ability of B16F1O cells. In addition, fenofibrate strongly sensitized BI6FIO cells to the proapoptotic drug staurosporine, further supporting the possibility that fenofibrate-induced down-regulation of Akt function contributes to fenofibrate-mediated inhibition of metastatic potential in this experimental model. CONCLUSIONS Our results show that the PPAR-dependent antimetastatic activity of fenofibrate involves down-regulation of Akt phosphorylation and suggest that supplementation with this drug may improve the effectiveness of melanoma chemotherapy.
Peroxisome proliferator-activated receptor alpha activation decreases metastatic potential of melanoma cells in vitro via down-regulation of Akt.
25344732
Polyhomeotic-like 3 (PHC3) is a ubiquitously expressed member of the polycomb gene family and part of the human polycomb complex hPRC-H. We found that in normal cells PHC3 associated with both hPRC-H complex components and with the transcription factor E2F6. In differentiating and confluent cells, PHC3 and E2F6 showed nuclear colocalization in a punctate pattern that resembled the binding of polycomb bodies to heterochromatin. This punctate pattern was not seen in proliferating cells suggesting that PHC3 may be part of an E2F6-polycomb complex that has been shown to occupy and silence target promoters in G0. Previous loss of heterozygosity (LoH) analyses had shown that the region containing PHC3 underwent frequent LoH in primary human osteosarcoma tumors. When we examined normal bone and human osteosarcoma tumors, we found loss of PHC3 expression in 36 of 56 osteosarcoma tumors. Sequence analysis revealed that PHC3 was mutated in nine of 15 primary osteosarcoma tumors. These findings suggest that loss of PHC3 may favor tumorigenesis by potentially disrupting the ability of cells to remain in G0.
PHC3, a component of the hPRC-H complex, associates with E2F6 during G0 and is lost in osteosarcoma tumors
25353658
CD4 T cell help is critical for the generation and maintenance of germinal centers (GCs), and T follicular helper (T(FH)) cells are the CD4 T cell subset required for this process. Signaling lymphocytic activation molecule (SLAM)-associated protein (SAP [SH2D1A]) expression in CD4 T cells is essential for GC development. However, SAP-deficient mice have only a moderate defect in T(FH) differentiation, as defined by common T(FH) surface markers. CXCR5(+) T(FH) cells are found within the GC, as well as along the boundary regions of T/B cell zones. In this study, we show that GC-associated T follicular helper (GC T(FH)) cells can be identified by their coexpression of CXCR5 and the GL7 epitope, allowing for phenotypic and functional analysis of T(FH) and GC T(FH) populations. GC T(FH) cells are a functionally discrete subset of further polarized T(FH) cells, with enhanced B cell help capacity and a specialized ability to produce IL-4 in a T(H)2-independent manner. Strikingly, SAP-deficient mice have an absence of the GC T(FH) cell subset and SAP(-) T(FH) cells are defective in IL-4 and IL-21 production. We further demonstrate that SLAM (Slamf1, CD150), a surface receptor that uses SAP signaling, is specifically required for IL-4 production by GC T(FH) cells. GC T(FH) cells require IL-4 and -21 production for optimal help to B cells. These data illustrate complexities of SAP-dependent SLAM family receptor signaling, revealing a prominent role for SLAM receptor ligation in IL-4 production by GC CD4 T cells but not in T(FH) cell and GC T(FH) cell differentiation.
Germinal center T follicular helper cell IL-4 production is dependent on signaling lymphocytic activation molecule receptor (CD150).
25355575
Since the beginning of the 1990s the public health situation in Russia has been characterized by an extremely high mortality and a significant reduction in life expectancy. Cardiovascular diseases remained the major cause of death. Only a few large population studies were conducted in Russia during this period. A total of 1968 men and 1737 women aged 18–75 years participated in a health survey in Arkhangelsk, Russia, over the period 1999–2000. Investigation included assessment of classic cardiovascular risk factors (family history, smoking, blood pressure, and blood lipids) along with general health variables. The paper presents sex specific data on risk factors for coronary heart disease. Though the cardiovascular mortality is high in Russia, the calculated risk for coronary heart disease (the Framingham risk score and the Norwegian risk score) was lower in all age groups of men and women in Arkhangelsk compared with studies from the Western Europe and USA. Our data suggest that high cardiovascular mortality in Russia may be driven not only by the classic risk factors for coronary heart disease.
High cardiovascular mortality in Russia cannot be explained by the classical risk factors. The Arkhangelsk study 2000
25365522
Wnt7a signals through its receptor Fzd7 to activate the planar-cell-polarity pathway and drive the symmetric expansion of satellite stem cells resulting in enhanced repair of skeletal muscle. In differentiated myofibres, we observed that Wnt7a binding to Fzd7 directly activates the Akt/mTOR growth pathway, thereby inducing myofibre hypertrophy. Notably, the Fzd7 receptor complex was associated with Gα(s) and PI(3)K and these components were required for Wnt7a to activate the Akt/mTOR growth pathway in myotubes. Wnt7a-Fzd7 activation of this pathway was completely independent of IGF-receptor activation. Together, these experiments demonstrate that Wnt7a-Fzd7 activates distinct pathways at different developmental stages during myogenic lineage progression, and identify a non-canonical anabolic signalling pathway for Wnt7a and its receptor Fzd7 in skeletal muscle.
Wnt7a/Fzd7 Signalling Directly Activates the Akt/mTOR Anabolic Growth Pathway in Skeletal Muscle
25373397
A new technique has been developed for the facile location of pseudouridylate (psi) residues in any RNA molecule. The method uses two known modification procedures which in combination uniquely identify U residues which have been converted into psi. The first procedure involves reaction of all U-like and G-like residues with N-cyclohexyl-N'-beta-(4-methylmorpholinium)ethylcarbodiimide p-tosylate (CMC), followed by alkaline removal of all CMC groups except those linked to the N3 of psi. This stops reverse transcription, resulting in a gel band which identifies the U residue. The second procedure is uridine-specific hydrazinolysis which cleaves the RNA chain at all U residues and produces a gel band upon reverse transcription. psi residues, being resistant to hydrazinolysis, are not cleaved and do not stop reverse transcription. This leads to the absence of a band at psi residues. The combined method can also distinguish psi from 5-methyluridine, 4-thiouridine, uridine-5-oxyacetic acid, and 2-thio-5-methylaminomethyluridine as shown by treating rRNA and tRNA species known to contain these modified bases at defined sites. By this procedure, four new sites for psi in Escherichia coli 23S RNA were discovered, and one was disproven. The four new sites are at positions 2457, 2504, 2580, and 2605. The erroneous site is at position 2555. These four new psi residues, which are all in or within 2-3 residues of the peptidyltransferase ring, are thus in a position to play a functional and/or structural role at the peptidyltransferase center.(ABSTRACT TRUNCATED AT 250 WORDS)
Four newly located pseudouridylate residues in Escherichia coli 23S ribosomal RNA are all at the peptidyltransferase center: analysis by the application of a new sequencing technique.
25388309
The hypoxia-inducible factor (HIF) prolyl hydroxylase (PHD) enzymes represent novel targets for the treatment of anemia, ulcerative colitis, and ischemic and metabolic disease inter alia. We have identified a novel small-molecule inhibitor of PHD, 1-(5-chloro-6-(trifluoromethoxy)-1H-benzoimidazol-2-yl)-1H-pyrazole-4-carboxylic acid (JNJ-42041935), through structure-based drug design methods. The pharmacology of JNJ-42041935 was investigated in enzyme, cellular, and whole-animal systems and was compared with other compounds described in the literature as PHD inhibitors. JNJ-42041935, was a potent (pK(I) = 7.3-7.9), 2-oxoglutarate competitive, reversible, and selective inhibitor of PHD enzymes. In addition, JNJ-42041935 was used to compare the effect of selective inhibition of PHD to intermittent, high doses (50 μg/kg i.p.) of an exogenous erythropoietin receptor agonist in an inflammation-induced anemia model in rats. JNJ-42041935 (100 μmol/kg, once a day for 14 days) was effective in reversing inflammation-induced anemia, whereas erythropoietin had no effect. The results demonstrate that JNJ-42041935 is a new pharmacological tool, which can be used to investigate PHD inhibition and demonstrate that PHD inhibitors offer great promise for the treatment of inflammation-induced anemia.
Pharmacological characterization of 1-(5-chloro-6-(trifluoromethoxy)-1H-benzoimidazol-2-yl)-1H-pyrazole-4-carboxylic acid (JNJ-42041935), a potent and selective hypoxia-inducible factor prolyl hydroxylase inhibitor.
25404036
Gap junctions play a fundamental role in intercellular communication in cardiac tissue. Various types of heart disease including hypertrophy and ischemia are associated with alterations of the spatial arrangement of gap junctions. Previous studies applied two-dimensional optical and electron-microscopy to visualize gap junction arrangements. In normal cardiomyocytes, gap junctions were primarily found at cell ends, but can be found also in more central regions. In this study, we extended these approaches toward three-dimensional reconstruction of gap junction distributions based on high-resolution scanning confocal microscopy and image processing. We developed methods for quantitative characterization of gap junction distributions based on analysis of intensity profiles along the principal axes of myocytes. The analyses characterized gap junction polarization at cell ends and higher-order statistical image moments of intensity profiles. The methodology was tested in rat ventricular myocardium. Our analysis yielded novel quantitative data on gap junction distributions. In particular, the analysis demonstrated that the distributions exhibit significant variability with respect to polarization, skewness, and kurtosis. We suggest that this methodology provides a quantitative alternative to current approaches based on visual inspection, with applications in particular in characterization of engineered and diseased myocardium. Furthermore, we propose that these data provide improved input for computational modeling of cardiac conduction.
Three-Dimensional Modeling and Quantitative Analysis of Gap Junction Distributions in Cardiac Tissue
25413327
Embryonic stem (ES) cell lines derived from human blastocysts have the developmental potential to form derivatives of all three embryonic germ layers even after prolonged culture. Here we describe the clonal derivation of two human ES cell lines, H9.1 and H9.2. At the time of the clonal derivation of the H9.1 and H9.2 ES cell lines, the parental ES cell line, H9, had already been continuously cultured for 6 months. After an additional 8 months of culture, H9.1 and H9.2 ES cell lines continued to: (1) actively proliferate, (2) express high levels of telomerase, and (3) retain normal karyotypes. Telomere lengths, while somewhat variable, were maintained between 8 and 12 kb in high-passage H9.1 and H9.2 cells. High-passage H9.1 and H9.2 cells both formed teratomas in SCID-beige mice that included differentiated derivatives of all three embryonic germ layers. These results demonstrate the pluripotency of single human ES cells, the maintenance of pluripotency during an extended period of culture, and the long-term self-renewing properties of cultured human ES cells. The remarkable developmental potential, proliferative capacity, and karyotypic stability of human ES cells distinguish them from adult cells.
Clonally derived human embryonic stem cell lines maintain pluripotency and proliferative potential for prolonged periods of culture.
25416944
PURPOSE Mutations in the leucine rich, glioma inactivated gene (LGI1) were recently described in a small number of families with autosomal dominant lateral temporal epilepsy (ADLTE). ADLTE is characterized by partial seizures with symptoms suggestive of a lateral temporal onset, including frequent auditory aura. Here we report the results of clinical and genetic analyses of two newly identified families with ADTLE. METHODS We identified two families whose seizure semiology was suggestive of ADLTE. Evaluation included a detailed history and neurologic examination, as well as collection of DNA. The coding sequence of the LGI1 gene from affected subjects from both families was analyzed for evidence of mutation. RESULTS Each patient had a history of partial seizures, often with secondary generalization earlier in the course. Auditory aura was reported by approximately two thirds of affected patients in each pedigree. Novel mutations in LGI1 were detected in both families. A heterozygous single-nucleotide deletion at position 329 (del 329C) was detected in affected individuals from one family, whereas patients from the second family had a nonsynonymous variation, corresponding to C435G. CONCLUSIONS We identified two novel mutations in the LGI1 gene. The phenotype of these two families was similar to that of other kindreds with ADLTE, as auditory aura was absent in one third of affected individuals. Our results further support that LGI1 mutations should be considered in patients with a history of partial seizures if the semiology of seizures is consistent with the onset in the lateral temporal lobe.
Autosomal dominant lateral temporal epilepsy: two families with novel mutations in the LGI1 gene.
25419778
Cellular senescence is a fundamental mechanism by which cells remain metabolically active yet cease dividing and undergo distinct phenotypic alterations, including upregulation of p16Ink4a , profound secretome changes, telomere shortening, and decondensation of pericentromeric satellite DNA. Because senescent cells accumulate in multiple tissues with aging, these cells and the dysfunctional factors they secrete, termed the senescence-associated secretory phenotype (SASP), are increasingly recognized as promising therapeutic targets to prevent age-related degenerative pathologies, including osteoporosis. However, the cell type(s) within the bone microenvironment that undergoes senescence with aging in vivo has remained poorly understood, largely because previous studies have focused on senescence in cultured cells. Thus in young (age 6 months) and old (age 24 months) mice, we measured senescence and SASP markers in vivo in highly enriched cell populations, all rapidly isolated from bone/marrow without in vitro culture. In both females and males, p16Ink4a expression by real-time quantitative polymerase chain reaction (rt-qPCR) was significantly higher with aging in B cells, T cells, myeloid cells, osteoblast progenitors, osteoblasts, and osteocytes. Further, in vivo quantification of senescence-associated distension of satellites (SADS), ie, large-scale unraveling of pericentromeric satellite DNA, revealed significantly more senescent osteocytes in old compared with young bone cortices (11% versus 2%, p < 0.001). In addition, primary osteocytes from old mice had sixfold more (p < 0.001) telomere dysfunction-induced foci (TIFs) than osteocytes from young mice. Corresponding with the age-associated accumulation of senescent osteocytes was significantly higher expression of multiple SASP markers in osteocytes from old versus young mice, several of which also showed dramatic age-associated upregulation in myeloid cells. These data show that with aging, a subset of cells of various lineages within the bone microenvironment become senescent, although senescent myeloid cells and senescent osteocytes predominantly develop the SASP. Given the critical roles of osteocytes in orchestrating bone remodeling, our findings suggest that senescent osteocytes and their SASP may contribute to age-related bone loss. © 2016 American Society for Bone and Mineral Research.
Identification of Senescent Cells in the Bone Microenvironment.
25420421
Little is known about the changes in white blood cells and platelets in children with falciparum malaria in endemic areas. We measured the white cell count (WCC) and platelets of 230 healthy children from the community, 1369 children admitted to hospital with symptomatic malaria, and 1461 children with other medical conditions. Children with malaria had a higher WCC compared with community controls, and leucocytosis was strongly associated with younger age, deep breathing, severe anaemia, thrombocytopenia and death. The WCC was not associated with a positive blood culture. In children with malaria, high lymphocyte and low monocyte counts were independently associated with mortality. A platelet count of less than 150 x 109/l was found in 56.7% of children with malaria, and was associated with age, prostration and parasite density, but not with bleeding problems or mortality. The mean platelet volume was also higher in children with malaria compared with other medical conditions. This may reflect early release from the bone marrow in response to peripheral platelet destruction. Thus, leucocytosis was associated with both severity and mortality in children with falciparum malaria, irrespective of bacteraemia, whereas thrombocytopenia, although very common, was not associated with adverse outcome.
Changes in white blood cells and platelets in children with falciparum malaria: relationship to disease outcome.
25435456
There is currently great interest in molecular therapies to treat various diseases, and this has prompted extensive efforts to achieve target-specific and controlled delivery of bioactive macromolecules (for example, proteins, antibodies, DNA and small interfering RNA) through the design of smart drug carriers. By contrast, the influence of the microenvironment in which the target cell resides and the effect it might have on the success of biomacromolecular therapies has been under-appreciated. The extracellular matrix (ECM) component of the cellular niche may be particularly important, as many diseases and injury disrupt the normal ECM architecture, the cell adhesion to ECM, and the subsequent cellular activities. This Review will discuss the importance of the ECM and the ECM–cell interactions on the cell response to bioactive macromolecules, and suggest how this information could lead to new criteria for the design of novel drug delivery systems.
Microenvironmental regulation of biomacromolecular therapies
25439264
Abstract Hyperhomocysteinemia has been suggested as a possible risk factor in women suffering from habitual abortions, placental abruption or infarcts, preeclampsia, and/or intrauterine growth retardation. However, little is known about the pathogenic mechanisms underlying the action of homocysteine. The present study investigated the in vitro ability of homocysteine to affect trophoblast gonadotropin secretion and to induce cell death. In primary human trophoblast cells, homocysteine treatment (20 μmol/L) resulted in cellular flattening and enlargement, extension of pseudopodia, and cellular vacuolization. Cellular detachment, apoptosis, and necrosis were favored. With in situ nick end labeling, we investigated DNA degradation, and we used M30 CytoDEATH to selectively stain the cytoplasm of apoptotic cells. Cytochrome c release from mitochondria to the cytosol and DNA cleavage in agarose gel have been investigated. Homocysteine, but not cysteine, induced trophoblast apoptosis and significantly reduced human chorionic gonadotropin secretion. These findings suggest that trophoblast cell death might represent a pathogenic mechanism by which homocysteine may cause pregnancy complications related to placental diseases.
Homocysteine Induces Trophoblast Cell Death with Apoptotic Features1
25440070
Testosterone (T) and its 5alpha-reduced metabolite, dihydrotestosterone (DHT), can decrease anxiety-like behavior; however, the mechanisms underlying these effects have not been established. First, we hypothesized that if T reduces anxiety-like behavior through actions of its 5alpha-reduced metabolite, DHT, then gonadectomy (GDX) would increase anxiety-like behavior, an effect which would be reversed by systemic administration of DHT. Second, we hypothesized that if T and DHT reduce anxiety-like behavior in part through actions at intracellular androgen receptors in the hippocampus, then administration of an androgen receptor antagonist, flutamide, directly to the hippocampus should increase anxiety-like behavior of intact and DHT-replaced, but not GDX, male rats. Inserts that were empty or contained flutamide were applied directly to the dorsal hippocampus of intact, GDX, or GDX and DHT-replaced rats 2 h prior to testing in the open field, elevated plus maze, or defensive freezing tasks. GDX rats exhibited significantly more anxiety-like behaviors than intact or DHT-replaced rats. Intact and DHT-replaced rats administered flutamide to the hippocampus showed significantly more anxiety-like behavior than did intact and DHT-replaced controls. However, flutamide alone did not increase anxiety-like behavior of GDX rats. Together, these findings suggest that androgens can decrease anxiety-like behavior of male rats in part through DHT's actions at androgen receptors in the hippocampus.
Intrahippocampal administration of an androgen receptor antagonist, flutamide, can increase anxiety-like behavior in intact and DHT-replaced male rats.
25451374
BACKGROUND More than 80% of deaths from cardiovascular disease are estimated to occur in low-income and middle-income countries, but the reasons are unknown. METHODS We enrolled 156,424 persons from 628 urban and rural communities in 17 countries (3 high-income, 10 middle-income, and 4 low-income countries) and assessed their cardiovascular risk using the INTERHEART Risk Score, a validated score for quantifying risk-factor burden without the use of laboratory testing (with higher scores indicating greater risk-factor burden). Participants were followed for incident cardiovascular disease and death for a mean of 4.1 years. RESULTS The mean INTERHEART Risk Score was highest in high-income countries, intermediate in middle-income countries, and lowest in low-income countries (P<0.001). However, the rates of major cardiovascular events (death from cardiovascular causes, myocardial infarction, stroke, or heart failure) were lower in high-income countries than in middle- and low-income countries (3.99 events per 1000 person-years vs. 5.38 and 6.43 events per 1000 person-years, respectively; P<0.001). Case fatality rates were also lowest in high-income countries (6.5%, 15.9%, and 17.3% in high-, middle-, and low-income countries, respectively; P=0.01). Urban communities had a higher risk-factor burden than rural communities but lower rates of cardiovascular events (4.83 vs. 6.25 events per 1000 person-years, P<0.001) and case fatality rates (13.52% vs. 17.25%, P<0.001). The use of preventive medications and revascularization procedures was significantly more common in high-income countries than in middle- or low-income countries (P<0.001). CONCLUSIONS Although the risk-factor burden was lowest in low-income countries, the rates of major cardiovascular disease and death were substantially higher in low-income countries than in high-income countries. The high burden of risk factors in high-income countries may have been mitigated by better control of risk factors and more frequent use of proven pharmacologic therapies and revascularization. (Funded by the Population Health Research Institute and others.).
Cardiovascular risk and events in 17 low-, middle-, and high-income countries.
25452937
Thyroid cancers are infiltrated with tumor-associated macrophages (TAMs), yet their role in cancer progression is not known. The objectives of this study were to characterize the density of TAMs in well-differentiated (WDTC), poorly differentiated (PDTC), and anaplastic thyroid cancers (ATC) and to correlate TAM density with clinicopathologic parameters. Immunohistochemistry was performed on tissue microarray sections from WDTC (n=33), PDTC (n=37), and ATC (n=20) using macrophage-specific markers. Electronic medical records were used to gather clinical and pathologic data. Follow-up information of PDTC patients was available for 0-12 years. In total, 9 out of 33 WDTC (27%), 20 out of 37 PDTC (54%), and 19 out of 20 ATC (95%) had an increased density of CD68(+) TAMs (> or = 10 per 0.28 mm(2); WDTC versus PDTC, P=0.03; WDTC versus ATC, P<0.0001; PDTC versus ATC, P<0.002). Increased TAMs in PDTC was associated with capsular invasion (P=0.034), extrathyroidal extension (P=0.009), and decreased cancer-related survival (P=0.009) compared with PDTC with a low density of TAMs. In conclusion, the density of TAMs is increased in advanced thyroid cancers. The presence of a high density of TAMs in PDTC correlates with invasion and decreased cancer-related survival. These results suggest that TAMs may facilitate tumor progression. As novel therapies directed against thyroid tumor cell-specific targets are being tested, the potential role of TAMs as potential modulators of the thyroid cancer behavior will need to be considered.
Increased density of tumor-associated macrophages is associated with decreased survival in advanced thyroid cancer.
25453683
OBJECTIVE T cell immunoglobulin and mucin domain (Tim) proteins are expressed by numerous immune cells, recognize phosphatidylserine on apoptotic cells, and function as costimulators or coinhibitors. Tim-1 is expressed by activated T cells but is also found on dendritic cells and B cells. Tim-4, present on macrophages and dendritic cells, plays a critical role in apoptotic cell clearance, regulates the number of phosphatidylserine-expressing activated T cells, and is genetically associated with low low-density lipoprotein and triglyceride levels. Because these functions of Tim-1 and Tim-4 could affect atherosclerosis, their modulation has potential therapeutic value in cardiovascular disease. APPROACH AND RESULTS ldlr(-/-) mice were fed a high-fat diet for 4 weeks while being treated with control (rat immunoglobulin G1) or anti-Tim-1 (3D10) or -Tim-4 (21H12) monoclonal antibodies that block phosphatidylserine recognition and phagocytosis. Both anti-Tim-1 and anti-Tim-4 treatments enhanced atherosclerosis by 45% compared with controls by impairment of efferocytosis and increasing aortic CD4(+)T cells. Consistently, anti-Tim-4-treated mice showed increased percentages of activated T cells and late apoptotic cells in the circulation. Moreover, in vitro blockade of Tim-4 inhibited efferocytosis of oxidized low-density lipoprotein-induced apoptotic macrophages. Although anti-Tim-4 treatment increased T helper cell (Th)1 and Th2 responses, anti-Tim-1 induced Th2 responses but dramatically reduced the percentage of regulatory T cells. Finally, combined blockade of Tim-1 and Tim-4 increased atherosclerotic lesion size by 59%. CONCLUSIONS Blockade of Tim-4 aggravates atherosclerosis likely by prevention of phagocytosis of phosphatidylserine-expressing apoptotic cells and activated T cells by Tim-4-expressing cells, whereas Tim-1-associated effects on atherosclerosis are related to changes in Th1/Th2 balance and reduced circulating regulatory T cells.
Blockade of Tim-1 and Tim-4 Enhances Atherosclerosis in Low-Density Lipoprotein Receptor-Deficient Mice.
25462689
We have investigated HO endonuclease-induced double-strand break (DSB) recombination and repair in a LACZ duplication plasmid in yeast. A 117-bp MATa fragment, embedded in one copy of LACZ, served as a site for initiation of a DSB when HO endonuclease was expressed. The DSB could be repaired using wild-type sequences located on a second, promoterless, copy of LACZ on the same plasmid. In contrast to normal mating-type switching, crossing-over associated with gene conversion occurred at least 50% of the time. The proportion of conversion events accompanied by exchange was greater when the two copies of LACZ were in direct orientation (80%), than when inverted (50%). In addition, the fraction of plasmids lost was significantly greater in the inverted orientation. The kinetics of appearance of intermediates and final products were also monitored. The repair of the DSB is slow, requiring at least an hour from the detection of the HO-cut fragments to completion of repair. Surprisingly, the appearance of the two reciprocal products of crossing over did not occur with the same kinetics. For example, when the two LACZ sequences were in the direct orientation, the HO-induced formation of a large circular deletion product was not accompanied by the appearance of a small circular reciprocal product. We suggest that these differences may reflect two kinetically separable processes, one involving only one cut end and the other resulting from the concerted participation of both ends of the DSB.
Genetic and physical analysis of double-strand break repair and recombination in Saccharomyces cerevisiae.
25475802
Here we show that the relaxation induced by stimulation of the vagus nerve in the presence of cholinergic (muscarinic) and adrenergic blockade in the isolated stomach of the guinea pig is mediated by nitric oxide (NO). This is substantiated by inhibition of vagal relaxation by NG-monomethyl-L-arginine, an inhibitor of NO synthesis. The effect of NG-monomethyl-L-arginine was partially reversed by coincubation with L-arginine but not with D-arginine. NO activates soluble guanylate cyclase, and relaxation of the stomach induced by vagal stimulation was prevented by an inhibitor of soluble guanylate cyclase, methylene blue, further supporting our conclusions. The relaxant effect of vagal stimulation was also ablated by hexamethonium, an inhibitor of ganglionic nicotinic receptors, thereby showing that ganglionic transmission did not rely on NO, through its release from preganglionic neurons. However, hexamethonium did not inhibit the gastric relaxation brought about by increasing the intragastric pressure, which is also mediated by NO as previously described by us. The selective inhibition by hexamethonium of only the vagally mediated relaxation but not of the pressure-induced relaxation of the stomach indicates the existence of at least two separate neuronal pathways able to generate NO and bring about gastric accommodation of food or fluid.
Nitroxergic nerves mediate vagally induced relaxation in the isolated stomach of the guinea pig.
25479072
Cytotoxic T cell (CTL) activation by antigen requires the specific detection of peptide–major histo-compatibility class I (pMHC) molecules on the target-cell surface by the T cell receptor (TCR). We examined the effect of mutations in the antigen-binding site of a Kb-restricted TCR on T cell activation, antigen binding and dissociation from antigen. These parameters were also examined for variants derived from a Kd-restricted peptide that was recognized by a CTL clone. Using these two independent systems, we show that T cell activation can be impaired by mutations that either decrease or increase the binding half-life of the TCR-pMHC interaction. Our data indicate that efficient T cell activation occurs within an optimal dwell-time range of TCR-pMHC interaction. This restricted dwell-time range is consistent with the exclusion of either extremely low or high affinity T cells from the expanded population during immune responses.
Efficient T cell activation requires an optimal dwell-time of interaction between the TCR and the pMHC complex
25483562
Insulin-regulated aminopeptidase (IRAP or oxytocinase) is a membrane-bound zinc-metallopeptidase that cleaves neuroactive peptides in the brain and produces memory enhancing effects when inhibited. We have determined the crystal structure of human IRAP revealing a closed, four domain arrangement with a large, mostly buried cavity abutting the active site. The structure reveals that the GAMEN exopeptidase loop adopts a very different conformation from other aminopeptidases, thus explaining IRAP's unique specificity for cyclic peptides such as oxytocin and vasopressin. Computational docking of a series of IRAP-specific cognitive enhancers into the crystal structure provides a molecular basis for their structure-activity relationships and demonstrates that the structure will be a powerful tool in the development of new classes of cognitive enhancers for treating a variety of memory disorders such as Alzheimer's disease.
Crystal structure of human insulin-regulated aminopeptidase with specificity for cyclic peptides.
25488034
Increases in the intracellular levels of reactive oxygen species (ROS), frequently referred to as oxidative stress, represents a potentially toxic insult which if not counteracted will lead to membrane dysfunction, DNA damage and inactivation of proteins. Chronic oxidative stress has numerous pathological consequences including cancer, arthritis and neurodegenerative disease. Glutathione-associated metabolism is a major mechanism for cellular protection against agents which generate oxidative stress. It is becoming increasingly apparent that the glutathione tripeptide is central to a complex multifaceted detoxification system, where there is substantial inter-dependence between separate component members. Glutathione participates in detoxification at several different levels, and may scavenge free radicals, reduce peroxides or be conjugated with electrophilic compounds. Thus, glutathione provides the cell with multiple defences not only against ROS but also against their toxic products. This article discusses how glutathione biosynthesis, glutathione peroxidases, glutathione S-transferases and glutathione S-conjugate efflux pumps function in an integrated fashion to allow cellular adaption to oxidative stress. Co-ordination of this response is achieved, at least in part, through the antioxidant responsive element (ARE) which is found in the promoters of many of the genes that are inducible by oxidative and chemical stress. Transcriptional activation through this enhancer appears to be mediated by basic leucine zipper transcription factors such as Nrf and small Maf proteins. The nature of the intracellular sensor(s) for ROS and thiol-active chemicals which induce genes through the ARE is described. Gene activation through the ARE appears to account for the enhanced antioxidant and detoxification capacity of normal cells effected by many cancer chemopreventive agents. In certain instances it may also account for acquired resistance of tumours to cancer chemotherapeutic drugs. It is therefore clear that determining the mechanisms involved in regulation of ARE-driven gene expression has enormous medical implications.
Glutathione and glutathione-dependent enzymes represent a co-ordinately regulated defence against oxidative stress.
25493293
Disadvantaged family socioeconomic status (SES) is often assumed to diminish parent training program effectiveness. In examining effects of SES, influences of initial problem severity have been largely ignored. In the present meta-analysis, we examined (a) whether there is a differential influence of SES on parent training effectiveness at immediate posttreatment and at 1-year follow-up-controlling for levels of initial problem severity--and (b) whether SES interacts with initial problem severity in its effect on program effectiveness. Seventy-five studies on parent training program effectiveness to reduce disruptive child behavior were included. Separate analyses were conducted for immediate posttreatment and approximately 1-year follow-up assessments. Immediately posttreatment, disadvantaged samples benefited less from parent training, but only when they had low levels of initial problem severity. At follow-up, disadvantaged samples benefited less from parent training regardless of initial problem severity. Initial problem severity was a strong predictor of effect sizes both immediately posttreatment and at follow-up. Parent training programs are equally effective for disadvantaged and nondisadvantaged families immediately posttreatment, at least when initial problems are severe. Maintenance of treatment gain, however, seems harder for disadvantaged families, suggesting that more sustained family support may be needed.
Does socioeconomic status matter? A meta-analysis on parent training effectiveness for disruptive child behavior.
25499612
Despite its key role in determining the stability and intensity of malaria transmission, the infectiousness of human populations to mosquitoes has rarely been estimated. Field-based analyses of malaria transmission have frequently relied on the prevalence of asexual parasites or gametocytes as proxies for infectiousness. We now summarize empirical data on human infectiousness from Africa and Papua New Guinea. Over a wide range of transmission intensities there is little relationship between the infectiousness of human populations to vector mosquitoes and mosquito-to-human transmission intensity. We compare these data with the predictions of a stochastic simulation model of Plasmodium falciparum epidemiology. This model predicted little variation in the infectiousness of the human population for entomologic inoculation rates (EIRs) greater than approximately 10 infectious bites per year, demonstrating that the lack of relationship between the EIR and the infectious reservoir can be explained without invoking any effects of acquired transmission-blocking immunity. The near absence of field data from areas with an EIR < 10 per year precluded validation of the model predictions for low EIR values. These results suggest that interventions reducing mosquito-to-human transmission will have little or no effect on human infectiousness at the levels of transmission found in most rural areas of sub-Saharan Africa. Unless very large reductions in transmission can be achieved, measures to prevent mosquito-to-human transmission need to be complemented with interventions that reduce the density or infectiousness of blood stage parasites.
Infectiousness of malaria-endemic human populations to vectors.
25504006
Growing evidence for intratumour heterogeneity informs us that single-site biopsies fall short of revealing the complete genomic landscape of a tumour. With an expanding repertoire of targeted agents entering the clinic, screening tumours for genomic aberrations is increasingly important, as is interrogating the tumours for resistance mechanisms upon disease progression. Multiple biopsies separated spatially and temporally are impractical, uncomfortable for the patient and not without risk. Here, we describe how circulating tumour cells (CTCs), captured from a minimally invasive blood test—and readily amenable to serial sampling—have the potential to inform intratumour heterogeneity and tumour evolution, although it remains to be determined how useful this will be in the clinic. Technologies for detecting and isolating CTCs include the validated CellSearch® system, but other technologies are gaining prominence. We also discuss how recent CTC discoveries map to mechanisms of haematological spread, previously described in preclinical models, including evidence for epithelial–mesenchymal transition, collective cell migration and cells with tumour-initiating capacity within the circulation. Advances in single-cell molecular analysis are enhancing our ability to explore mechanisms of metastasis, and the combination of CTC and cell-free DNA assays are anticipated to provide invaluable blood-borne biomarkers for real-time patient monitoring and treatment stratification.
Molecular analysis of circulating tumour cells—biology and biomarkers
25510546
Increased lipid supply causes beta cell death, which may contribute to reduced beta cell mass in type 2 diabetes. We investigated whether endoplasmic reticulum (ER) stress is necessary for lipid-induced apoptosis in beta cells and also whether ER stress is present in islets of an animal model of diabetes and of humans with type 2 diabetes. Expression of genes involved in ER stress was evaluated in insulin-secreting MIN6 cells exposed to elevated lipids, in islets isolated from db/db mice and in pancreas sections of humans with type 2 diabetes. Overproduction of the ER chaperone heat shock 70 kDa protein 5 (HSPA5, previously known as immunoglobulin heavy chain binding protein [BIP]) was performed to assess whether attenuation of ER stress affected lipid-induced apoptosis. We demonstrated that the pro-apoptotic fatty acid palmitate triggers a comprehensive ER stress response in MIN6 cells, which was virtually absent using non-apoptotic fatty acid oleate. Time-dependent increases in mRNA levels for activating transcription factor 4 (Atf4), DNA-damage inducible transcript 3 (Ddit3, previously known as C/EBP homologous protein [Chop]) and DnaJ homologue (HSP40) C3 (Dnajc3, previously known as p58) correlated with increased apoptosis in palmitate- but not in oleate-treated MIN6 cells. Attenuation of ER stress by overproduction of HSPA5 in MIN6 cells significantly protected against lipid-induced apoptosis. In islets of db/db mice, a variety of marker genes of ER stress were also upregulated. Increased processing (activation) of X-box binding protein 1 (Xbp1) mRNA was also observed, confirming the existence of ER stress. Finally, we observed increased islet protein production of HSPA5, DDIT3, DNAJC3 and BCL2-associated X protein in human pancreas sections of type 2 diabetes subjects. Our results provide evidence that ER stress occurs in type 2 diabetes and is required for aspects of the underlying beta cell failure.
Endoplasmic reticulum stress contributes to beta cell apoptosis in type 2 diabetes
25513319
Metabolic pathway reprogramming is a hallmark of cancer cell growth and survival and supports the anabolic and energetic demands of these rapidly dividing cells. The underlying regulators of the tumor metabolic program are not completely understood; however, these factors have potential as cancer therapy targets. Here, we determined that upregulation of the oncogenic transcriptional coregulator steroid receptor coactivator 2 (SRC-2), also known as NCOA2, drives glutamine-dependent de novo lipogenesis, which supports tumor cell survival and eventual metastasis. SRC-2 was highly elevated in a variety of tumors, especially in prostate cancer, in which SRC-2 was amplified and overexpressed in 37% of the metastatic tumors evaluated. In prostate cancer cells, SRC-2 stimulated reductive carboxylation of α-ketoglutarate to generate citrate via retrograde TCA cycling, promoting lipogenesis and reprogramming of glutamine metabolism. Glutamine-mediated nutrient signaling activated SRC-2 via mTORC1-dependent phosphorylation, which then triggered downstream transcriptional responses by coactivating SREBP-1, which subsequently enhanced lipogenic enzyme expression. Metabolic profiling of human prostate tumors identified a massive increase in the SRC-2-driven metabolic signature in metastatic tumors compared with that seen in localized tumors, further implicating SRC-2 as a prominent metabolic coordinator of cancer metastasis. Moreover, SRC-2 inhibition in murine models severely attenuated the survival, growth, and metastasis of prostate cancer. Together, these results suggest that the SRC-2 pathway has potential as a therapeutic target for prostate cancer.
Coactivator SRC-2-dependent metabolic reprogramming mediates prostate cancer survival and metastasis.
25515662
Synthetic peptides such as P60stc autophosphorylation site peptides and angiotensin are indiscriminately phosphorylated by protein tyrosine kinases. The observation has led to the general belief that protein tyrosine kinases are highly promiscuous, displaying littlein vitro site specificity. In recent years, evidence has been accumulating to indicate that such a belief requires close examination. Synthetic peptides showing high substrate activity for specific groups of protein tyrosine kinases have been obtained. Systematic modification of certain substrate peptides suggests that kinase substrate determinants reside with specific amino acid residues proximal to the target tyrosine. A number of protein kinases have been shown to be regulated by tyrosine phosphorylation at specific sites by highly specific protein tyrosine kinases. These and other selected biochemical studies that contribute to the evolving view ofin vitro substrate specificity of protein tyrosine kinases are reviewed.
In vitro substrate specificity of protein tyrosine kinases
25515907
OBJECTIVE To determine the relative accuracy of clinic measurements and home blood pressure monitoring compared with ambulatory blood pressure monitoring as a reference standard for the diagnosis of hypertension. DESIGN Systematic review with meta-analysis with hierarchical summary receiver operating characteristic models. Methodological quality was appraised, including evidence of validation of blood pressure measurement equipment. DATA SOURCES Medline (from 1966), Embase (from 1980), Cochrane Database of Systematic Reviews, DARE, Medion, ARIF, and TRIP up to May 2010. Eligibility criteria for selecting studies Eligible studies examined diagnosis of hypertension in adults of all ages using home and/or clinic blood pressure measurement compared with those made using ambulatory monitoring that clearly defined thresholds to diagnose hypertension. RESULTS The 20 eligible studies used various thresholds for the diagnosis of hypertension, and only seven studies (clinic) and three studies (home) could be directly compared with ambulatory monitoring. Compared with ambulatory monitoring thresholds of 135/85 mm Hg, clinic measurements over 140/90 mm Hg had mean sensitivity and specificity of 74.6% (95% confidence interval 60.7% to 84.8%) and 74.6% (47.9% to 90.4%), respectively, whereas home measurements over 135/85 mm Hg had mean sensitivity and specificity of 85.7% (78.0% to 91.0%) and 62.4% (48.0% to 75.0%). CONCLUSIONS Neither clinic nor home measurement had sufficient sensitivity or specificity to be recommended as a single diagnostic test. If ambulatory monitoring is taken as the reference standard, then treatment decisions based on clinic or home blood pressure alone might result in substantial overdiagnosis. Ambulatory monitoring before the start of lifelong drug treatment might lead to more appropriate targeting of treatment, particularly around the diagnostic threshold.
Relative effectiveness of clinic and home blood pressure monitoring compared with ambulatory blood pressure monitoring in diagnosis of hypertension: systematic review
25516011
Mouse bone marrow hematopoietic stem cells were isolated with the use of a variety of phenotypic markers. These cells can proliferate and differentiate with approximately unit efficiency into myelomonocytic cells, B cells, or T cells. Thirty of these cells are sufficient to save 50 percent of lethally irradiated mice, and to reconstitute all blood cell types in the survivors.
Purification and characterization of mouse hematopoietic stem cells.
25519138
Bacteria such as Escherichia coli will often consume one sugar at a time when fed multiple sugars, in a process known as carbon catabolite repression. The classic example involves glucose and lactose, where E. coli will first consume glucose, and only when it has consumed all of the glucose will it begin to consume lactose. In addition to that of lactose, glucose also represses the consumption of many other sugars, including arabinose and xylose. In this work, we characterized a second hierarchy in E. coli, that between arabinose and xylose. We show that, when grown in a mixture of the two pentoses, E. coli will consume arabinose before it consumes xylose. Consistent with a mechanism involving catabolite repression, the expression of the xylose metabolic genes is repressed in the presence of arabinose. We found that this repression is AraC dependent and involves a mechanism where arabinose-bound AraC binds to the xylose promoters and represses gene expression. Collectively, these results demonstrate that sugar utilization in E. coli involves multiple layers of regulation, where cells will consume first glucose, then arabinose, and finally xylose. These results may be pertinent in the metabolic engineering of E. coli strains capable of producing chemical and biofuels from mixtures of hexose and pentose sugars derived from plant biomass.
Regulation of arabinose and xylose metabolism in Escherichia coli.
25523969
Small non-coding microRNAs (miRNAs) contribute to cancer development and progression, and are differentially expressed in normal tissues and cancers. However, the specific role of miRNAs in the metastatic process is still unknown. To seek a specific miRNA expression signature characterizing the metastatic phenotype of solid tumours, we performed a miRNA microarray analysis on 43 paired primary tumours (ten colon, ten bladder, 13 breast, and ten lung cancers) and one of their related metastatic lymph nodes. We identified a metastatic cancer miRNA signature comprising 15 overexpressed and 17 underexpressed miRNAs. Our results were confirmed by qRT-PCR analysis. Among the miRNAs identified, some have a well-characterized association with cancer progression, eg miR-10b, miR-21, miR-30a, miR-30e, miR-125b, miR-141, miR-200b, miR-200c, and miR-205. To further support our data, we performed an immunohistochemical analysis for three well-defined miRNA gene targets (PDCD4, DHFR, and HOXD10 genes) on a small series of paired colon, breast, and bladder cancers, and one of their metastatic lymph nodes. We found that the immunohistochemical expression of these targets significantly follows the corresponding miRNA deregulation. Our results suggest that specific miRNAs may be directly involved in cancer metastasis and that they may represent a novel diagnostic tool in the characterization of metastatic cancer gene targets.
MicroRNA expression profiling of human metastatic cancers identifies cancer gene targets.
25536577
We created a visualization tool called Circos to facilitate the identification and analysis of similarities and differences arising from comparisons of genomes. Our tool is effective in displaying variation in genome structure and, generally, any other kind of positional relationships between genomic intervals. Such data are routinely produced by sequence alignments, hybridization arrays, genome mapping, and genotyping studies. Circos uses a circular ideogram layout to facilitate the display of relationships between pairs of positions by the use of ribbons, which encode the position, size, and orientation of related genomic elements. Circos is capable of displaying data as scatter, line, and histogram plots, heat maps, tiles, connectors, and text. Bitmap or vector images can be created from GFF-style data inputs and hierarchical configuration files, which can be easily generated by automated tools, making Circos suitable for rapid deployment in data analysis and reporting pipelines.
Circos: an information aesthetic for comparative genomics.
25543207
Platelet inhibitors are the mainstay treatment for patients with vascular diseases. The current 'gold standard' antiplatelet agent clopidogrel has several pharmacological and clinical limitations that have prompted the search for more effective platelet antagonists. The candidates include various blockers of the purinergic P2Y12 receptor such as prasugrel, an oral irreversible thienopyridine; two adenosine triphosphate analogues that bind reversibly to the P2Y12 receptor: ticagrelor (oral) and cangrelor (intravenous); elinogrel, a direct-acting reversible P2Y12 receptor inhibitor (the only antiplatelet compound that can be administered both intravenously and orally); BX 667, an orally active and reversible small-molecule P2Y12 receptor antagonist; SCH 530348, SCH 205831, SCH 602539 and E5555, highly selective and orally active antagonists on the protease-activated receptor 1. A number of drugs also hit new targets: terutroban, an oral, selective and specific inhibitor of the thromboxane receptor; ARC1779, a second-generation, nuclease resistant aptamer which inhibits von Willebrand factor-dependent platelet aggregation; ALX-0081, a bivalent humanized nanobody targeting the GPIb binding site of von Willebrand factor and AJW200, an IgG4 monoclonal antibody of von Willebrand factor. The pharmacology and clinical profiles of new platelet antagonists indicate that they provide more consistent, more rapid and more potent platelet inhibition than agents currently used. Whether these potential advantages will translate into clinical advantages will require additional comparisons in properly powered, randomized, controlled trials.
Pharmacokinetic, pharmacodynamic and clinical profile of novel antiplatelet drugs targeting vascular diseases.
25550665
Mutations in BLM cause Bloom's syndrome, a disorder associated with cancer predisposition and chromosomal instability. We investigated whether BLM plays a role in ensuring the faithful chromosome segregation in human cells. We show that BLM-defective cells display a higher frequency of anaphase bridges and lagging chromatin than do isogenic corrected derivatives that eptopically express the BLM protein. In normal cells undergoing mitosis, BLM protein localizes to anaphase bridges, where it colocalizes with its cellular partners, topoisomerase IIIalpha and hRMI1 (BLAP75). Using BLM staining as a marker, we have identified a class of ultrafine DNA bridges in anaphase that are surprisingly prevalent in the anaphase population of normal human cells. These so-called BLM-DNA bridges, which also stain for the PICH protein, frequently link centromeric loci, and are present at an elevated frequency in cells lacking BLM. On the basis of these results, we propose that sister-chromatid disjunction is often incomplete in human cells even after the onset of anaphase. We present a model for the action of BLM in ensuring complete sister chromatid decatenation in anaphase.
BLM is required for faithful chromosome segregation and its localization defines a class of ultrafine anaphase bridges.
25562234
BACKGROUND Corin has been suggested to be associated with hypertension by cell- and animal-based studies. However, the association still lacks population-based evidence which critically promotes translation from basic research to clinical and preventive practice. Here, we aimed to explore the association in a general population of China. METHODS From January to May 2010, we conducted a cross-sectional study in 2,498 participants aged above 30 years, residing in Gusu district of Suzhou. Serum soluble corin and blood pressure were measured. RESULTS Hypertensive participants had a higher level of serum corin than nonhypertensive participants (median (interquartile range): 1,836.83 (1,497.85-2,327.87) pg/ml vs. 1,579.14 (1,322.18-1,956.82) pg/ml, P < 0.001). Higher serum corin was positively associated with prevalent hypertension (odds ratio (OR) = 2.01, P < 0.001). In the multiple analysis, participants in the third (OR = 1.43, P = 0.007) and fourth (OR = 1.96, P < 0.001) quartiles had significantly increased odds of hypertension compared to those in the lowest quartile of serum corin. ORs of hypertension positively and significantly increased with serum corin levels (P for trend <0.001). Further subgroup analysis showed that ORs of hypertension associated with high corin (over the median level of serum corin: 1,689.20 pg/ml) were still significant in subgroups by age, body mass index, total cholesterol, low-density lipoprotein cholesterol, and fasting plasma glucose (all P < 0.05). CONCLUSIONS Our study showed that hypertensive participants had an increased serum corin level compared to those without hypertension. This finding suggests that corin may play a role in the pathology of hypertension.
Association Between High Serum Soluble Corin and Hypertension: A Cross-Sectional Study in a General Population of China.
25571386
BACKGROUND Two inflammatory disorders, type 1 diabetes and celiac disease, cosegregate in populations, suggesting a common genetic origin. Since both diseases are associated with the HLA class II genes on chromosome 6p21, we tested whether non-HLA loci are shared. METHODS We evaluated the association between type 1 diabetes and eight loci related to the risk of celiac disease by genotyping and statistical analyses of DNA samples from 8064 patients with type 1 diabetes, 9339 control subjects, and 2828 families providing 3064 parent-child trios (consisting of an affected child and both biologic parents). We also investigated 18 loci associated with type 1 diabetes in 2560 patients with celiac disease and 9339 control subjects. RESULTS Three celiac disease loci--RGS1 on chromosome 1q31, IL18RAP on chromosome 2q12, and TAGAP on chromosome 6q25--were associated with type 1 diabetes (P<1.00x10(-4)). The 32-bp insertion-deletion variant on chromosome 3p21 was newly identified as a type 1 diabetes locus (P=1.81x10(-8)) and was also associated with celiac disease, along with PTPN2 on chromosome 18p11 and CTLA4 on chromosome 2q33, bringing the total number of loci with evidence of a shared association to seven, including SH2B3 on chromosome 12q24. The effects of the IL18RAP and TAGAP alleles confer protection in type 1 diabetes and susceptibility in celiac disease. Loci with distinct effects in the two diseases included INS on chromosome 11p15, IL2RA on chromosome 10p15, and PTPN22 on chromosome 1p13 in type 1 diabetes and IL12A on 3q25 and LPP on 3q28 in celiac disease. CONCLUSIONS A genetic susceptibility to both type 1 diabetes and celiac disease shares common alleles. These data suggest that common biologic mechanisms, such as autoimmunity-related tissue damage and intolerance to dietary antigens, may be etiologic features of both diseases.
Shared and distinct genetic variants in type 1 diabetes and celiac disease.
25576204
Malignant cells often display defects in autophagy, an evolutionarily conserved pathway for degrading long-lived proteins and cytoplasmic organelles. However, as yet, there is no genetic evidence for a role of autophagy genes in tumor suppression. The beclin 1 autophagy gene is monoallelically deleted in 40-75% of cases of human sporadic breast, ovarian, and prostate cancer. Therefore, we used a targeted mutant mouse model to test the hypothesis that monoallelic deletion of beclin 1 promotes tumorigenesis. Here we show that heterozygous disruption of beclin 1 increases the frequency of spontaneous malignancies and accelerates the development of hepatitis B virus-induced premalignant lesions. Molecular analyses of tumors in beclin 1 heterozygous mice show that the remaining wild-type allele is neither mutated nor silenced. Furthermore, beclin 1 heterozygous disruption results in increased cellular proliferation and reduced autophagy in vivo. These findings demonstrate that beclin 1 is a haplo-insufficient tumor-suppressor gene and provide genetic evidence that autophagy is a novel mechanism of cell-growth control and tumor suppression. Thus, mutation of beclin 1 or other autophagy genes may contribute to the pathogenesis of human cancers.
Promotion of tumorigenesis by heterozygous disruption of the beclin 1 autophagy gene.
25589047
CONTEXT Fatal adverse events (FAEs) have been reported in cancer patients treated with the widely used angiogenesis inhibitor bevacizumab in combination with chemotherapy. Currently, the role of bevacizumab in treatment-related mortality is not clear. OBJECTIVE To perform a systematic review and meta-analysis of published randomized controlled trials (RCTs) to determine the overall risk of FAEs associated with bevacizumab. DATA SOURCES PubMed, EMBASE, and Web of Science databases as well as abstracts presented at American Society of Clinical Oncology conferences from January 1966 to October 2010 were searched to identify relevant studies. STUDY SELECTION AND DATA EXTRACTION Eligible studies included prospective RCTs in which bevacizumab in combination with chemotherapy or biological therapy was compared with chemotherapy or biological therapy alone. Summary incidence rates, relative risks (RRs), and 95% confidence intervals (CIs) were calculated using fixed- or random-effects models. DATA SYNTHESIS A total of 10,217 patients with a variety of advanced solid tumors from 16 RCTs were included in the analysis. The overall incidence of FAEs with bevacizumab was 2.5% (95% CI, 1.7%-3.9%). Compared with chemotherapy alone, the addition of bevacizumab was associated with an increased risk of FAEs, with an RR of 1.46 (95% CI, 1.09-1.94; P = .01; incidence, 2.5% vs 1.7%). This association varied significantly with chemotherapeutic agents (P = .045) but not with tumor types (P = .13) or bevacizumab doses (P = .16). Bevacizumab was associated with an increased risk of FAEs in patients receiving taxanes or platinum agents (RR, 3.49; 95% CI, 1.82-6.66; incidence, 3.3% vs 1.0%) but was not associated with increased risk of FAEs when used in conjunction with other agents (RR, 0.85; 95% CI, 0.25-2.88; incidence, 0.8% vs 0.9%). The most common causes of FAEs were hemorrhage (23.5%), neutropenia (12.2%), and gastrointestinal tract perforation (7.1%). CONCLUSION In a meta-analysis of RCTs, bevacizumab in combination with chemotherapy or biological therapy, compared with chemotherapy alone, was associated with increased treatment-related mortality.
Treatment-related mortality with bevacizumab in cancer patients: a meta-analysis.
25597580
New neurons are generated in the adult hippocampus throughout life by neural stem/progenitor cells (NSCs), and neurogenesis is a plastic process responsive to external stimuli. We show that canonical Notch signaling through RBP-J is required for hippocampal neurogenesis. Notch signaling distinguishes morphologically distinct Sox2(+) NSCs, and within these pools subpopulations can shuttle between mitotically active or quiescent. Radial and horizontal NSCs respond selectively to neurogenic stimuli. Physical exercise activates the quiescent radial population whereas epileptic seizures induce expansion of the horizontal NSC pool. Surprisingly, reduced neurogenesis correlates with a loss of active horizontal NSCs in aged mice rather than a total loss of stem cells, and the transition to a quiescent state is reversible to rejuvenate neurogenesis in the brain. The discovery of multiple NSC populations with Notch dependence but selective responses to stimuli and reversible quiescence has important implications for the mechanisms of adaptive learning and also for regenerative therapy.
Quiescent and active hippocampal neural stem cells with distinct morphologies respond selectively to physiological and pathological stimuli and aging.
25599283
Vitamin D may play a role in glucose metabolism. A low vitamin D level has been associated with increased risk of diabetes mellitus, but the association has not been confirmed in Asians. Our objective was to examine the association of serum 25-hydroxyvitamin D [25(OH)D] levels with insulin resistance and diabetes mellitus in Korean adults based on a large population-based survey. Cross-sectional analyses were carried out on 5787 Korean adults (2453 men and 3334 women) who were 20 y or older and participated in the Fourth Korea NHANES conducted in 2008. Diabetes mellitus was defined as fasting plasma glucose ≥7 mmol/L or current use of oral hypoglycemic agents or insulin. Insulin resistance was estimated by homeostatic model assessment for insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI). Compared to individuals with a sufficient serum 25(OH)D concentration ≥75 nmol/L, the OR (95% CI) for diabetes mellitus were 1.73 (1.09-2.74), 1.30 (0.91-1.84), and 1.40 (0.99-1.98) for serum 25(OH)D concentrations <25, 25 to <50, and 50 to <75 nmol/L, respectively, after multiple adjustments (P-trend < 0.0001). Furthermore, the serum 25(OH)D level was inversely associated with HOMA-IR (β = -0.061; P = 0.001) and positively associated with QUICKI (β = 0.059; P = 0.001) in overweight or obese participants. In conclusion, a low serum vitamin D concentration is associated with a high risk of diabetes mellitus in Korean adults and the concentration is inversely associated with insulin resistance in those who are overweight or obese.
Low serum vitamin D is associated with high risk of diabetes in Korean adults.
25602549
Cells of the immune system have evolved various molecular mechanisms to sense their environment and react to alterations of self. NK cells are lymphocytes with effector and regulatory functions, which are remarkably adaptable to changes in self. In a study published in this issue of the JCI, Tarek and colleagues report the clinical benefits of manipulating NK cell adaptation to self in an innovative mAb-based therapy against neuroblastoma (NB). This novel therapeutic strategy should stimulate further research on NK cell therapies.
When NK cells overcome their lack of education.
25606339
TLR3 has been implicated in the pathogenesis of several viral infections, including SIV- and HIV-1-induced inflammation and AIDS. However the molecular mechanisms of these TLR3-mediated effects are not known, and it is not known whether HIV interacts with cellular TLR3 to affect disease process. Here we investigate the effects of TLR3 ligands on HIV-1 transactivation using both primary human macrophages and cells containing integrated copies of the HIV-1 promoter. We demonstrate that TLR3 activation induced upregulation of transcription factors such as c-Jun, CCAAT/enhancer-binding protein alpha (CEBPA), signal transducer and activator of transcription (STAT)-1, STAT-2, RELB, and nuclear factor kappa-B1 (NFκB1), most of which are known to regulate the HIV promoter activity. We also demonstrate that TLR3 activation increased HIV-1 transactivation via the c-Jun N-terminal kinase (JNK) and NFκB pathways. This was associated with epigenetic modifications, including decreased histone deacetylase activity, increased histone acetyl transferase (HAT) activity, and increased acetylation of histones H3 and H4 at lysine residues in the nucleosome-0 and nucleosome-1 of the HIV-1 promoter. However, prolonged TLR3 activation decreased HIV-1 transactivation, decreased HAT activity and Tat transcription, and suppressed viral replication. Overall, data suggests that TLR3 can act as viral sensor to mediate viral transactivation, cellular signaling, innate immune response, and inflammation in HIV-infected humans. Our study provides novel insights into the molecular basis for these TLR3-mediated effects.
Toll-like receptor-3 mediates HIV-1 transactivation via NFκB and JNK pathways and histone acetylation, but prolonged activation suppresses Tat and HIV-1 replication.
25612629
Although a moderate-sized patent ductus arteriosus (PDA) needs to be closed by the time a child is 1-2 years old, there is great uncertainty about whether it needs to be closed during the neonatal period. Although 95% of neonatologists believe that a moderate-sized PDA should be closed if it persists in infants (born before 28 weeks) who still require mechanical ventilation, the number of neonatologists who treat a PDA when it occurs in infants who do not require mechanical ventilation varies widely. Both the high likelihood of spontaneous ductus closure and the absence of randomized controlled trials, specifically addressing the risks and benefits of neonatal ductus closure, add to the current uncertainty. New information suggests that early pharmacologic treatment has several important short-term benefits for the preterm newborn. By contrast, ductus ligation, while eliminating the detrimental effects of a PDA on lung development, may create its own set of morbidities that counteract many of the benefits derived from ductus closure.
Patent ductus arteriosus: are current neonatal treatment options better or worse than no treatment at all?
25623469
A newly emerging family of phosphatases that are members of the haloacid dehalogenase superfamily contains the catalytic motif DXDX(T/V). A member of this DXDX(T/V) phosphatase family known as Dullard was recently shown to be a potential regulator of neural tube development in Xenopus [Satow R, Chan TC, Asashima M (2002) Biochem Biophys Res Commun 295:85-91]. Herein, we demonstrate that human Dullard and the yeast protein Nem1p perform similar functions in mammalian cells and yeast cells, respectively. In addition to similarity in primary sequence, Dullard and Nem1p possess similar domains and show similar substrate preferences, and both localize to the nuclear envelope. Additionally, we show that human Dullard can rescue the aberrant nuclear envelope morphology of nem1Delta yeast cells, functionally replacing Nem1p. Finally, Nem1p, has been shown to deposphorylate the yeast phosphatidic acid phosphatase Smp2p [Santos-Rosa H, Leung J, Grimsey N, Peak-Chew S, Siniossoglou S (2005) EMBO J 24:1931-1941], and we show that Dullard dephosphorylates the mammalian phospatidic acid phosphatase, lipin. Therefore, we propose that Dullard participates in a unique phosphatase cascade regulating nuclear membrane biogenesis, and that this cascade is conserved from yeast to mammals.
A conserved phosphatase cascade that regulates nuclear membrane biogenesis.
25628793
Endometriosis is an estrogen-dependent disease affecting up to 10% of all premenopausal women. There is evidence that different endometriosis sites show distinct local estrogen concentration, which, in turn, might be due to a unique local estrogen metabolism. We aimed to investigate whether there was a site-specific regulation of selected enzymes responsible for the oxidative metabolism of estrogens in biopsy samples and endometrial and endometriotic stromal cells. Cytochrome P450 (CYP) 1A1 and CYP1B1 mRNA and protein expressions in deep-infiltrating (rectal, retossigmoidal, and uterossacral) lesions, superficial (ovarian and peritoneal) lesions, and eutopic and healthy (control) endometrium were evaluated by real-time PCR and western blot. Using a cross-sectional study design with 58 premenopausal women who were not under hormonal treatment, we were able to identify an overall increased CYP1A1 and CYP1B1 mRNA expression in superficial lesions compared with the healthy endometrium. CYP1A1 mRNA expression in superficial lesions was also greater than in the eutopic endometrium. Interestingly, we found a similar pattern of CYP1A1 and CYP1B1 expression in in vitro stromal cells isolated from ovarian lesions (n=3) when compared with stromal cells isolated from either rectum lesions or eutopic endometrium. In contradiction, there was an increased half-life of estradiol (measured by HPLC-MS-MS) in ovarian endometriotic stromal cells compared with paired eutopic stromal endometrial cells. Our results indicate that there is a site-dependent regulation of CYP1A1 and CYP1B1 in ovarian/peritoneal lesions and ovarian endometriotic stromal cells, whereas a slower metabolism is taking place in these cells.
Increased expression of CYP1A1 and CYP1B1 in ovarian/peritoneal endometriotic lesions.
25629722
The histone H3 Lys 9 (H3K9) methyltransferase Eset is an epigenetic regulator critical for the development of the inner cell mass (ICM). Although ICM-derived embryonic stem (ES) cells are normally unable to contribute to the trophectoderm (TE) in blastocysts, we find that depletion of Eset by shRNAs leads to differentiation with the formation of trophoblast-like cells and induction of trophoblast-associated gene expression. Using chromatin immmunoprecipitation (ChIP) and sequencing (ChIP-seq) analyses, we identified Eset target genes with Eset-dependent H3K9 trimethylation. We confirmed that genes that are preferentially expressed in the TE (Tcfap2a and Cdx2) are bound and repressed by Eset. Single-cell PCR analysis shows that the expression of Cdx2 and Tcfap2a is also induced in Eset-depleted morula cells. Importantly, Eset-depleted cells can incorporate into the TE of a blastocyst and, subsequently, placental tissues. Coimmunoprecipitation and ChIP assays further demonstrate that Eset interacts with Oct4, which in turn recruits Eset to silence these trophoblast-associated genes. Our results suggest that Eset restricts the extraembryonic trophoblast lineage potential of pluripotent cells and links an epigenetic regulator to key cell fate decision through a pluripotency factor.
Eset partners with Oct4 to restrict extraembryonic trophoblast lineage potential in embryonic stem cells.
25641414
OBJECTIVE To determine rates of suicide associated with pregnancy by the type of pregnancy. DESIGN Register linkage study. Information on suicides in women of reproductive age was linked with the Finnish birth, abortion, and hospital discharge registers to find out how many women who committed suicide had had a completed pregnancy during her last year of life. SETTING Nationwide data from Finland. SUBJECTS Women who committed suicide in 1987-94. RESULTS There were 73 suicides associated with pregnancy, representing 5.4% of all suicides in women in this age group. The mean annual suicide rate was 11.3 per 100,000. The suicide rate associated with birth was significantly lower (5.9) and the rates associated with miscarriage (18.1) and induced abortion (34.7) were significantly higher than in the population. The risk associated with birth was higher among teenagers and that associated with abortion was increased in all age groups. Women who had committed a suicide tended to come from lower social classes and were more likely to be unmarried than other women who had had a completed pregnancy. CONCLUSIONS The increased risk of suicide after an induced abortion indicates either common risk factors for both or harmful effects of induced abortion on mental health.
Suicides after pregnancy in Finland, 1987-94: register linkage study.
25643818
AIMS Lactic acidosis is a well recognized complication of biguanide therapy which is potentially serious. Although the prevalence of metformin-associated lactic acidosis (MALA) is much lower than that associated with phenformin, it is still being reported sporadically which raises concerns for the practising clinicians. We review the currently available world-wide data of the prevalence of MALA, the risk factors for its development and the current practical guidelines on the use of metformin to minimize the risk of this potential hazard. METHODS An extensive literature search was conducted from both Medline and Ovid (1965-98) using the following keywords: 'Type 2 diabetes mellitus', 'oral hypoglycaemic drugs', 'biguanides', 'metformin-associated lactic acidosis' and 'renal impairment'. RESULTS MALA was found to be a very rare clinical entity, being 20 times less common than phenformin-associated lactic acidosis. Amongst all the risk factors, renal impairment appears to be the major precipitating factor for the development of MALA in metformin-treated patients. We also found cases of MALA where no precipitating factors were identified and the underlying mechanism in these cases remains unclear. Practical recommendations of metformin use to minimize the risk of MALA have been listed based on previous reports. CONCLUSIONS The low prevalence of MALA is comparable to the prevalence of sulphonylurea-induced hypoglycaemia. Metformin has many beneficial metabolic effects in the management of Type 2 diabetes mellitus. Provided that the recommended guidelines for metformin use are strictly adhered to, its widespread use would be safe and the incidence of MALA will be further reduced.
Metformin-associated lactic acidosis: a rare or very rare clinical entity?
25649545
Inborn errors of the genes encoding two of the four human JAKs (JAK3 and TYK2) and three of the six human STATs (STAT1, STAT3, and STAT5B) have been described. We review the disorders arising from mutations in these five genes, highlighting the way in which the molecular and cellular pathogenesis of these conditions has been clarified by the discovery of inborn errors of cytokines, hormones, and their receptors, including those interacting with JAKs and STATs. The phenotypic similarities between mice and humans lacking individual JAK-STAT components suggest that the functions of JAKs and STATs are largely conserved in mammals. However, a wide array of phenotypic differences has emerged between mice and humans carrying biallelic null alleles of JAK3, TYK2, STAT1, or STAT5B. Moreover, the high degree of allelic heterogeneity at the human JAK3, TYK2, STAT1, and STAT3 loci has revealed highly diverse immunological and clinical phenotypes, which had not been anticipated.
Inborn errors of human JAKs and STATs.
25649714
OBJECTIVE To establish the mental health needs of homeless children and families before and after rehousing. DESIGN Cross sectional, longitudinal study. SETTING City of Birmingham. SUBJECTS 58 rehoused families with 103 children aged 2-16 years and 21 comparison families of low socioeconomic status in stable housing, with 54 children. MAIN OUTCOME MEASURES Children's mental health problems and level of communication; mothers' mental health problems and social support one year after rehousing. RESULTS Mental health problems remained significantly higher in rehoused mothers and their children than in the comparison group (mothers 26% v 5%, P = 0.04; children 39% v 11%, P = 0.0003). Homeless mothers continued to have significantly less social support at follow up. Mothers with a history of abuse and poor social integration were more likely to have children with persistent mental health problems. CONCLUSIONS Homeless families have a high level of complex needs that cannot be met by conventional health services and arrangements. Local strategies for rapid rehousing into permanent accommodation, effective social support and health care for parents and children, and protection from violence and intimidation should be developed and implemented.
Mental health problems of homeless children and families: longitudinal study.
25653703
The possible role of motor development on psychological function is once again a topic of great theoretical and practical importance. The revival of this issue has stemmed from a different approach to the topic, away from Gesell's interest in the long-term prediction of psychological functions from early motoric assessments, toward an attempt to understand how the acquisition of motor skills orchestrates psychological changes. This paper describes how the acquisition of one motor skill, prone locomotion, has been linked to developmental changes in an infant's ability to regulate posture based on information available in patterns of optic flow. It is argued that the onset of prone locomotion presses the infant to differentiate spatially delimited regions of optic flow to effectively and efficiently control the important subtasks nested within the larger task of locomotion, namely, steering, attending to the surface of support, and maintaining postural control. Following this argument, a research program is described that aims to determine if locomotor experience is causally linked to improvements in the ability to functionalize peripheral optic flow for postural control or whether locomotor experience is merely a maturational forecaster of such improvements. Finally, a hypothesis is put forward that links the emergence of wariness of heights to infants' ability to regulate posture on the basis of peripheral optic flow. The paper's overarching theoretical point is the principle of probabilistic epigenesis, which states that one developmental acquisition produces experiences that bring about a host of new developmental changes in the same and different domains.
The flip side of perception-action coupling: locomotor experience and the ontogeny of visual-postural coupling.
25657127
Urease, a nickel-dependent metalloenzyme, is synthesized by plants, some bacteria, and fungi. It catalyzes the hydrolysis of urea into ammonia and carbon dioxide. Although the amino acid sequences of plant and bacterial ureases are closely related, some biological activities differ significantly. Plant ureases but not bacterial ureases possess insecticidal properties independent of its ureolytic activity. To date, the structural information is available only for bacterial ureases although the jack bean urease (Canavalia ensiformis; JBU), the best-studied plant urease, was the first enzyme to be crystallized in 1926. To better understand the biological properties of plant ureases including the mechanism of insecticidal activity, we initiated the structural studies on some of them. Here, we report the crystal structure of JBU, the first plant urease structure, at 2.05 A resolution. The active-site architecture of JBU is similar to that of bacterial ureases containing a bi-nickel center. JBU has a bound phosphate and covalently modified residue (Cys592) by beta-mercaptoethanol at its active site, and the concomitant binding of multiple inhibitors (phosphate and beta-mercaptoethanol) is not observed so far in bacterial ureases. By correlating the structural information of JBU with the available biophysical and biochemical data on insecticidal properties of plant ureases, we hypothesize that the amphipathic beta-hairpin located in the entomotoxic peptide region of plant ureases might form a membrane insertion beta-barrel as found in beta-pore-forming toxins.
Crystal structure of the first plant urease from jack bean: 83 years of journey from its first crystal to molecular structure.
25670099
Using differential interference contrast optics, combined with cinematography, we have studied the morphological changes that the living, syncytial embryo undergoes from stage 10 through 14 of Drosophila embryogenesis, that is just prior to and during formation of the cellular blastoderm. We have supplemented these studies with data collected from fixed, stained, whole embryos. The following information has been obtained. The average duration of nuclear cycles 10, 11, 12 and 13 is about 9, 10, 12 and 21 min, respectively (25 degrees C). In these four cycles, the duration of that portion of the mitotic period that lacks a discrete nuclear envelope is 3, 3, 3 and 5 min, respectively. The length of nuclear cycle 14 varies in a position-specific manner throughout the embryo, the shortest cycles being of 65 min duration. During nuclear cycles 10 through 13, it is commonly observed in living embryos that the syncytial blastoderm nuclei enter (and leave) mitosis in one of two waves that originate nearly simultaneously from the opposite anterior and posterior poles of the embryo, and terminate in its midregion. From our preparations of quick-frozen embryos, we estimate that these mitotic waves take on average about half a minute to travel over the embryonic surface from pole to equator. The yolk nuclei, which remain in the core of the embryo when the rest of the nuclei migrate to the periphery, divide in synchrony with the migrating nuclei at nuclear cycles 8 and 9, and just after the now peripherally located nuclei at nuclear cycle 10. After cycle 10, these yolk nuclei cease dividing and become polyploid. The syncytial embryo has at least three distinct levels of cytoskeletal organization: structured domains of cytoplasm are organized around each blastoderm nucleus; radially directed tracks orient colchicine-sensitive saltatory transport throughout the peripheral cytoplasm; and a long-range organization of the core of the embryo makes possible coherent movements of the large inner yolk mass in concert with each nuclear cycle. This highly organized cytoplasm may be involved in providing positional information for the important process of nuclear determination that is known to occur during these stages.
Studies of nuclear and cytoplasmic behaviour during the five mitotic cycles that precede gastrulation in Drosophila embryogenesis.
25677651
Microbe-macrophage interactions play a central role in the pathogenesis of many infections. The ability of some bacterial pathogens to induce macrophage apoptosis has been suggested to contribute to their ability to elude innate immune responses and successfully colonize the host. Here, we provide evidence that activation of liver X receptors (LXRs) and retinoid X receptors (RXRs) inhibits apoptotic responses of macrophages to macrophage colony-stimulating factor (M-CSF) withdrawal and several inducers of apoptosis. In addition, combined activation of LXR and RXR protected macrophages from apoptosis caused by infection with Bacillus anthracis, Escherichia coli, and Salmonella typhimurium. Expression-profiling studies demonstrated that LXR and RXR agonists induced the expression of antiapoptotic regulators, including AIM/CT2, Bcl-X(L), and Birc1a. Conversely, LXR and RXR agonists inhibited expression of proapoptotic regulators and effectors, including caspases 1, 4/11, 7, and 12; Fas ligand; and Dnase1l3. The combination of LXR and RXR agonists was more effective than either agonist alone at inhibiting apoptosis in response to various inducers of apoptosis, and it acted synergistically to induce expression of AIM/CT2. Inhibition of AIM/CT2 expression in response to LXR/RXR agonists partially reversed their antiapoptotic effects. These findings reveal unexpected roles of LXRs and RXRs in the control of macrophage survival and raise the possibility that LXR/RXR agonists may be exploited to enhance innate immunity to bacterial pathogens that induce apoptotic programs as a strategy for evading host responses.
Activation of liver X receptors and retinoid X receptors prevents bacterial-induced macrophage apoptosis.
25682129
The sequence-specific binding to DNA is crucial for the p53 tumor suppressor function. To investigate the constraints imposed on p53-DNA recognition by nucleosomal organization, we studied binding of the p53 DNA binding domain (p53DBD) and full-length wild-type p53 protein to a single p53 response element (p53RE) placed near the nucleosomal dyad in six rotational settings. We demonstrate that the strongest p53 binding occurs when the p53RE in the nucleosome is bent in the same direction as observed for the p53-DNA complexes in solution and in co-crystals. The p53RE becomes inaccessible, however, if its orientation in the core particle is changed by approximately 180 degrees. Our observations indicate that the orientation of the binding sites on a nucleosome may play a significant role in the initial p53-DNA recognition and subsequent cofactor recruitment.
p53 binding to nucleosomal DNA depends on the rotational positioning of DNA response element.
25687558
The genetically obese (ob/ob) mouse exhibits defective thermoregulatory responses to cold exposure. Pathophysiological explanations for this phenomenon have focused on abnormalities in intracellular metabolism or insensitivity of peripheral tissues to the thermogenic effects of catecholamines. Because the sympathetic nervous system (SNS) is subject to feedback regulation, a peripheral impairment in thermogenesis should be associated with a compensatory increase in SNS activity. To examine SNS activity in the ob/ob mouse, norepinephrine (NE) turnover was measured in heart and interscapular brown adipose tissue (IBAT) of ob/ob and lean mice. The results from studies utilizing radiolabeled NE or inhibition of NE biosynthesis with alpha-methyl-p-tyrosine to measure NE turnover demonstrated reductions in SNS activity of 33-56% in heart and of 45-73% in IBAT in ob/ob mice at ambient temperature (22 degrees C) compared with measurements in lean controls. During cold exposure (4 degrees C) NE turnover increased in heart and IBAT to a similar extent in both ob/ob and lean mice, but NE turnover rates in heart, and probably in IBAT as well, remained lower in the obese mice than in the lean despite the gradual development of hypothermia in the ob/ob mice during this period. Administration of naltrexone, a long-acting opiate antagonist, failed to reverse the suppression of SNS activity observed in the ob/ob mice. These data indicate that diminished SNS activity in ob/ob mice may be an additional factor contributing to the defective thermogenesis characteristic of these animals.
Diminished sympathetic nervous system activity in genetically obese (ob/ob) mouse.
25690516
The aim of the study was to evaluate whether treatment with recombinant human growth hormone (rhGH) affects the quality of life of young adults who were diagnosed as idiopathic short stature (ISS) during childhood, and whether their quality of life and aspects of the personality are different from normal. Experiences and expectations concerning rhGH treatment of the subjects and their parents were also investigated. Eighty-nine subjects were included into the study: 24 subjects (16M, 8F) were treated with rhGH from childhood, whereas 65 subjects (40M, 25F) were never treated. At the time of the interview all subjects had attained final height [mean (SD) -2.3 (0.9) SDS for Dutch references], and the age of the treated subjects was 20.5 (1.0) y, and 25.7 (3.5) y of the control subjects (p < 0.001). The level of education was similar, but the treated subjects had less often a partner compared to the control subjects (adjusted for age and gender, p < 0.001). The Nottingham Health Profile and Short Form 36 Health Survey showed no difference in general health state between treated and control subjects, and the healthy Dutch age-specific references (norm group). Although 74% of the subjects reported one or more negative events related to their height, and 61% would like to be taller, only 22% and 11% were willing to trade-off at Time Trade-Off and Standard Gamble, respectively. The personality of the subjects, which was measured by the Minnesota Multiphasic Personality Inventory, was not different from the norm group. The satisfaction with the rhGH treatment was high, as it had caused 12 (8) cm and 13 (7) cm gain in final height according to the subjects and parents, respectively. Based on initial predicted adult height (Bayley & Pinneau), this gain was only 3.3 (5.6) cm. We concluded that although the treated subjects had a partner less often when compared to the control subjects, the quality of life of subjects with ISS at adult age is normal and appears not to be affected by rhGH therapy, The treated subjects were very satisfied with the treatment, probably by overestimation of the final height gain.
Quality of life of young adults with idiopathic short stature: effect of growth hormone treatment. Dutch Growth Hormone Working Group.
25690564
Homicide is one of the leading causes of death among African-American and Hispanic men. We investigated how neighborhood characteristics associated with social disadvantage explain racial/ethnic homicide gaps in 10 U.S. cities. The test hypotheses were that (1) higher concentrations of African-Americans and Hispanics would be associated with higher homicide rates and (2) the relationship between racial/ethnic concentration and homicide would be attenuated after adjusting for neighborhood characteristics (e.g., unemployment, median household income, low educational attainment, and female headship). The test hypotheses were examined using separate Poisson regression models, which adjusted for spatial autocorrelation. Homicide rates were greater in neighborhoods with higher concentrations of African-Americans and Hispanics than in other groups, and the association of neighborhood racial/ethnic concentration with homicide was reduced after adjusting for neighborhood social disadvantage variables, especially percent female head of household and percent persons with less than a high school education. We also found that the relationship between neighborhood racial/ethnic concentration and homicide was explained more by social disadvantage variables in some cities than in others. Based on our findings, policy makers may wish to consider implementation of policies that (1) expand early childhood education programs and higher education opportunities and (2) encourage economic and community development initiatives in socially disadvantaged neighborhoods.
Neighborhood Racial/Ethnic Concentration, Social Disadvantage, and Homicide Risk: An Ecological Analysis of 10 U.S. Cities
25691541
How to manage the preterm patent ductus arteriosus (PDA) remains a conundrum. On the one hand, physiology and statistical association with adverse outcomes suggest that it is pathological. On the other hand, clinical trials of treatment strategies have failed to show any long-term benefit. Ultrasound studies of PDA have suggested that the haemodynamic impact may be much earlier after birth than previously thought (in the first hours); however, we still do not know when to treat PDA. Studies that have tested symptomatic or pre-symptomatic treatment are mainly historical and have not tested the effect of no treatment. Prophylactic treatment is the best-studied regimen but improvements in some short-term outcomes do not translate to any difference in longer-term outcomes. Neonatologists have been reluctant to engage in trials that test treatment against almost never treating. Observations of very early postnatal haemodynamic significance suggest that targeting treatment on the basis of the early postnatal constrictive response of the duct may optimize benefits. A pilot trial of this strategy showed reduction in the incidence of pulmonary haemorrhage but more trials of this strategy are needed.
Preterm patent ductus arteriosus: A continuing conundrum for the neonatologist?
25691878
Countries have reached universal health coverage by different paths and with varying health systems. Nonetheless, the trajectory toward universal health coverage regularly has three common features. The first is a political process driven by a variety of social forces to create public programmes or regulations that expand access to care, improve equity, and pool financial risks. The second is a growth in incomes and a concomitant rise in health spending, which buys more health services for more people. The third is an increase in the share of health spending that is pooled rather than paid out-of-pocket by households. This pooled share is sometimes mobilised as taxes and channelled through governments that provide or subsidise care--in other cases it is mobilised in the form of contributions to mandatory insurance schemes. The predominance of pooled spending is a necessary condition (but not sufficient) for achieving universal health coverage. This paper describes common patterns in countries that have successfully provided universal access to health care and considers how economic growth, demographics, technology, politics, and health spending have intersected to bring about this major development in public health.
Political and economic aspects of the transition to universal health coverage.
25725663
Cigarette smoke is the leading cause of the development of various lung diseases including lung cancer through triggering oxidant stress and inflammatory responses which contributed to the lesions of normal human bronchial epithelial (NHBE) cell. Wedelolactone (WEL), a natural compound from Eclipta prostrata L., has been found to possess the inhibitive effects on the proliferation and growth of cancers. In the present study, we investigated the effects of WEL on NHBE cell injury induced by cigarette smoke extract (CSE) in vitro. It showed that the pretreatment WEL (2.5-20μM) resulted in a significant protective effect on 10% CSE-induced cell death in NHBE cells. The pretreatment with WEL dose-dependently and significantly reversed the activities of SOD, CAT, GSH and the level of MDA to normal level. We also found that the protein expression levels of COX-2 and ICAM-1 which are related to inflammatory response were remarkably reduced by WEL compared with 10% CSE treatment. Additionally, WEL also reduced the expressions of antioxidases including NAD(P)H dehydrogenase:Quinone 1 (NQO1) and heme oxygenase-1 (HO-1). Moreover, Nrf2 inhibitor all-trans-retinoic acid (ATRA) decreased remarkably their expressions. These results suggest that WEL protects NHBE cell against CSE-induced injury through modulating Nrf2 pathway. Our study indicates that WEL may be a new potential protective agent against CSE-induced lung injury.
Wedelolactone protects human bronchial epithelial cell injury against cigarette smoke extract-induced oxidant stress and inflammation responses through Nrf2 pathway.
25726838
The role of immune responses in tumor development is a central issue for tumor biology and immunology. IL-17 is an important cytokine for inflammatory and autoimmune diseases. Although IL-17-producing cells are detected in cancer patients and tumor-bearing mice, the role of IL-17 in tumor development is controversial, and mechanisms remain to be fully elucidated. In the current study, we found that the development of tumors was inhibited in IL-17R-deficient mice. A defect in IFN-gammaR increased tumor growth, whereas tumor growth was inhibited in mice that were deficient in both IL-17R and IFN-gammaR compared with wild-type animals. Further experiments showed that neutralization of IL-17 by Abs inhibited tumor growth in wild-type mice, whereas systemic administration of IL-17 promoted tumor growth. The IL-17R deficiency increased CD8 T cell infiltration, whereas it reduced the infiltration of myeloid-derived suppressor cells (MDSCs) in tumors. In contrast, administration of IL-17 inhibited CD8 T cell infiltration and increased MDSCs in tumors. Further analysis indicated that IL-17 was required for the development and tumor-promoting activity of MDSCs in tumor-bearing mice. These data demonstrate that IL-17-mediated responses promote tumor development through the induction of tumor-promoting microenvironments at tumor sites. IL-17-mediated regulation of MDSCs is a primary mechanism for its tumor-promoting effects. The study provides novel insights into the role of IL-17 in tumor development and has major implications for targeting IL-17 in treatment of tumors.
IL-17 promotes tumor development through the induction of tumor promoting microenvironments at tumor sites and myeloid-derived suppressor cells.
25732836
PURPOSE Circulating tumor cells (CTCs) and [(18)F]fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) are two new promising tools for therapeutic monitoring. In this study, we compared the prognostic value of CTC and FDG-PET/CT monitoring during systemic therapy for metastatic breast cancer (MBC). PATIENTS AND METHODS A retrospective analyses of 115 MBC patients who started a new line of therapy and who had CTC counts and FDG-PET/CT scans performed at baseline and at 9 to 12 weeks during therapy (midtherapy) was performed. Patients were categorized according to midtherapy CTC counts as favorable (ie, < five CTCs/7.5 mL blood) or unfavorable (> or = five CTCs/7.5 mL blood) outcomes. CTC counts and FDG-PET/CT response at midtherapy were compared, and univariate and multivariate analyses were performed to identify factors associated with survival. RESULTS In 102 evaluable patients, the median overall survival time was 14 months (range, 1 to > 41 months). Midtherapy CTC levels correlated with FDG-PET/CT response in 68 (67%) of 102 evaluable patients. In univariate analysis, midtherapy CTC counts and FDG-PET/CT response predicted overall survival (P < .001 and P = .001, respectively). FDG-PET/CT predicted overall survival (P = .0086) in 31 (91%) of 34 discordant patients who had fewer than five CTCs at midtherapy. Only midtherapy CTC levels remained significant in a multivariate analysis (P = .004). CONCLUSION Detection of five or more CTCs during therapeutic monitoring can accurately predict prognosis in MBC beyond metabolic response. FDG-PET/CT deserves a role in patients who have fewer than five CTCs at midtherapy. Prospective trials should evaluate the most sensitive and cost-effective modality for therapeutic monitoring in MBC.
Circulating tumor cells and [18F]fluorodeoxyglucose positron emission tomography/computed tomography for outcome prediction in metastatic breast cancer.