Alzheimer’s Disease Risk Gene CD33 Inhibits Microglial Uptake of Amyloid Beta

Abstract: The transmembrane protein CD33 is a sialic acid-binding immunoglobulin-like lectin that regulates innate immunity but has no known functions in the brain. We have previously shown that the CD33 gene is a risk factor for Alzheimer's disease (AD). Here, we observed increased expression of CD33 in microglial cells in AD brain. The minor allele of the CD33 SNP rs3865444, which confers protection against AD, was associated with reductions in both CD33 expression and insoluble amyloid beta 42 (Aβ42) levels in AD brain. Furthermore, the numbers of CD33-immunoreactive microglia were positively correlated with insoluble Aβ42 levels and plaque burden in AD brain. CD33 inhibited uptake and clearance of Aβ42 in microglial cell cultures. Finally, brain levels of insoluble Aβ42 as well as amyloid plaque burden were markedly reduced in APP(Swe)/PS1(ΔE9)/CD33(-/-) mice. Therefore, CD33 inactivation mitigates Aβ pathology and CD33 inhibition could represent a novel therapy for AD.


A longitudinal diffusion tensor imaging study assessing white matter fiber tracts after sports-related concussion.

Abstract: The extent of structural injury in sports-related concussion (SRC) is central to the course of recovery, long-term effects, and the decision to return to play. In the present longitudinal study, we used diffusion tensor imaging (DTI) to assess white matter (WM) fiber tract integrity within 2 days, 2 weeks, and 2 months of concussive injury. Participants were right-handed male varsity contact-sport athletes (20.2±1.0 years of age) with a medically diagnosed SRC (no loss of consciousness). They were compared to right-handed male varsity non-contact-sport athletes serving as controls (19.9±1.7 years). We found significantly increased radial diffusivity (RD) in concussed athletes (n=12; paired t-test, tract-based spatial statistics; p<0.025) at 2 days, when compared to the 2-week postinjury time point. The increase was found in a cluster of right hemisphere voxels, spanning the posterior limb of the internal capsule (IC), the retrolenticular part of the IC, the inferior longitudinal fasciculus, the inferior fronto-occipital fasciculus (sagittal stratum), and the anterior thalamic radiation. Post-hoc, univariate, between-group (controls vs. concussed), mixed-effects analysis of the cluster showed significantly higher RD at 2 days (p=0.002), as compared to the controls, with a trend in the same direction at 2 months (p=0.11). Results for fractional anisotropy (FA) in the same cluster showed a similar, but inverted, pattern; FA was decreased at 2 days and at 2 months postinjury, when compared to healthy controls. At 2 weeks postinjury, no statistical differences between concussed and control athletes were found with regard to either RD or FA. These results support the hypothesis of increased RD and reduced FA within 72 h postinjury, followed by recovery that may extend beyond 2 weeks. RD appears to be a sensitive measure of concussive injury.


Notch targets and their regulation.

Abstract: The proteolytic cleavages elicited by activation of the Notch receptor release an intracellular fragment, Notch intracellular domain, which enters the nucleus to activate the transcription of targets. Changes in transcription are therefore a major output of this pathway. However, the Notch outputs clearly differ from cell type to cell type. In this review we discuss current understanding of Notch targets, the mechanisms involved in their transcriptional regulation, and what might underlie the activation of different sets of targets in different cell types.


MicroRNA-21 is up-regulated in allergic airway inflammation and regulates IL-12p35 expression.

Abstract: Allergic airway inflammation is characterized by marked in situ changes in gene and protein expression, yet the role of microRNAs (miRNAs), a new family of key mRNA regulatory molecules, in this process has not yet been reported. Using a highly sensitive microarray-based approach, we identified 21 miRNAs with differential expression between doxycycline-induced lung-specific IL-13 transgenic mice (with allergic airway inflammation) and control mice. In particular, we observed overexpression of miR-21 and underexpression of miR-1 in the induced IL-13 transgenic mice compared with control mice. These findings were validated in two independent models of allergen-induced allergic airway inflammation and in IL-4 lung transgenic mice. Although IL-13-induced miR-21 expression was IL-13Ralpha1 dependent, allergen-induced miR-21 expression was mediated mainly independent of IL-13Ralpha1 and STAT6. Notably, predictive algorithms identified potential direct miR-21 targets among IL-13-regulated lung transcripts, such as IL-12p35 mRNA, which was decreased in IL-13 transgenic mice. Introduction of pre-miR-21 dose dependently inhibited cellular expression of a reporter vector harboring the 3'-untranslated region of IL-12p35. Moreover, mutating miR-21 binding sites in IL-12p35 3'-untranslated region abrogated miR-21-mediated repression. In summary, we have identified a miRNA signature in allergic airway inflammation, which includes miR-21 that modulates IL-12, a molecule germane to Th cell polarization.


COPD: epidemiology, prevalence, morbidity and mortality, and disease heterogeneity.

Abstract: COPD continues to cause a heavy health and economic burden both in the United States and around the world. Some of the risk factors for COPD are well-known and include smoking, occupational exposures, air pollution, airway hyperresponsiveness, asthma, and certain genetic variations, although many questions, such as why < 20% of smokers develop significant airway obstruction, remain. Precise definitions of COPD vary and are frequently dependent on an accurate diagnosis of the problem by a physician. These differences in the definition of COPD can have large effects on the estimates of COPD in the population. Furthermore, evidence that COPD represents several different disease processes with potentially different interventions continues to emerge. In most of the world, COPD prevalence and mortality are still increasing and likely will continue to rise in response to increases in smoking, particularly by women and adolescents. Resources aimed at smoking cessation and prevention, COPD education and early detection, and better treatment will be of the most benefit in our continuing efforts against this important cause of morbidity and mortality.


Mutant KRAS is a druggable target for pancreatic cancer.

Abstract: Pancreatic ductal adenocarcinoma (PDA) represents an unmet therapeutic challenge. PDA is addicted to the activity of the mutated KRAS oncogene which is considered so far an undruggable therapeutic target. We propose an approach to target KRAS effectively in patients using RNA interference. To meet this challenge, we have developed a local prolonged siRNA delivery system (Local Drug EluteR, LODER) shedding siRNA against the mutated KRAS (siG12D LODER). The siG12D LODER was assessed for its structural, release, and delivery properties in vitro and in vivo. The effect of the siG12D LODER on tumor growth was assessed in s.c. and orthotopic mouse models. KRAS silencing effect was further assessed on the KRAS downstream signaling pathway. The LODER-encapsulated siRNA was stable and active in vivo for 155 d. Treatment of PDA cells with siG12D LODER resulted in a significant decrease in KRAS levels, leading to inhibition of proliferation and epithelial-mesenchymal transition. In vivo, siG12D LODER impeded the growth of human pancreatic tumor cells and prolonged mouse survival. We report a reproducible and safe delivery platform based on a miniature biodegradable polymeric matrix, for the controlled and prolonged delivery of siRNA. This technology provides the following advantages: (i) siRNA is protected from degradation; (ii) the siRNA is slowly released locally within the tumor for prolonged periods; and (iii) the siG12D LODER elicits a therapeutic effect, thereby demonstrating that mutated KRAS is indeed a druggable target.


Basics of PD-1 in self-tolerance, infection, and cancer immunity

Abstract: Successful cancer treatment requires understanding host immune response against tumor cells. PD-1 belongs to the CD28 superfamily of receptors that work as “checkpoints” of immune activation. PD-1 maintains immune self-tolerance to prevent autoimmunity and controls T-cell reaction during infection to prevent excessive tissue damage. Tumor cells that arise from normal tissue acquire mutations that can be targeted by lymphocytes. Accumulating lines of evidence suggest that tumor cells evade host immune attack by expressing physiological PD-1 ligands and stimulating PD-1 on the lymphocytes. Based on this idea, researchers have successfully demonstrated that systemic administration of monoclonal antibodies that inhibit the binding of PD-1 to the ligands reactivated T cells and augmented the anti-cancer immune response. In this review, I summarize the basics of T-cell biology and its regulation by PD-1 and discuss the current understanding and questions about this multifaceted molecule.


The histone demethylases Jhdm1a/1b enhance somatic cell reprogramming in a vitamin-C-dependent manner.

Abstract: Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) resets the epigenome to an embryonic-like state. Vitamin C enhances the reprogramming process, but the underlying mechanisms are unclear. Here we show that the histone demethylases Jhdm1a/1b are key effectors of somatic cell reprogramming downstream of vitamin C. We first observed that vitamin C induces H3K36me2/3 demethylation in mouse embryonic fibroblasts in culture and during reprogramming. We then identified Jhdm1a/1b, two known vitamin-C-dependent H3K36 demethylases, as potent regulators of reprogramming through gain- and loss-of-function approaches. Furthermore, we found that Jhdm1b accelerates cell cycle progression and suppresses cell senescence during reprogramming by repressing the Ink4/Arf locus. Jhdm1b also cooperates with Oct4 to activate the microRNA cluster 302/367, an integral component of the pluripotency machinery. Our results therefore reveal a role for H3K36me2/3 in cell fate determination and establish a link between histone demethylases and vitamin-C-induced reprogramming.


Perinatal mortality in rural China: retrospective cohort study.

Abstract:
OBJECTIVES To explore the use of local civil registration data to assess the perinatal mortality in a typical rural county in a less developed province in China, 1999-2000.
 DESIGN Retrospective cohort study. Pregnancies in a cohort of women followed from registration of pregnancy to outcome of infant seven days after birth.
 SETTING Routine family planning records in 20 rural townships in eastern China.    SUBJECTS 3697 pregnancies registered by the local family planning system during 1999.
 MAIN OUTCOME MEASURES Abortions, stillbirths, early neonatal mortality, perinatal mortality.
 RESULTS Only three cases were lost to follow up. The average age of the women at pregnancy was 25.9 years. Three hundred and twelve pregnancies were aborted and 240 ended in miscarriage (total 552, 15%). The perinatal mortality rate was 69 per 1000 births, the rate of stillbirth was 24 per 1000 births, and the early neonatal mortality was 46 per 1000 live births. The early neonatal mortality was 29 in boys and 69 in girls per 1000 live births. The perinatal mortality rate increased notably with parity and was higher in townships having lower income per capita.
 CONCLUSIONS The family planning system at the most local level is a useful data source for studying perinatal mortality in rural China. The perinatal mortality rate in the study county was higher than previously reported for both rural and urban areas in China. The results by parity and sex of the infant raise concern over the impact of the one child policy.


Lessons from sudden coronary death: a comprehensive morphological classification scheme for atherosclerotic lesions.

Abstract: This review will reconsider the current paradigm for understanding the critical, final steps in the progression of atherosclerotic lesions. That scheme, largely an outgrowth of observations of autopsy tissues by Davies and colleagues,1 2 asserts that the cause of death in atherosclerotic coronary artery disease is rupture of an advanced atherosclerotic lesion. Although this assumption may be partially true, recent autopsy studies suggest that it is incomplete.   To reconsider this paradigm, we reexamined the morphological classification scheme for lesions proposed by the American Heart Association (AHA).3 4 This scheme is difficult to use for 2 reasons. First, it uses a very long list of roman numerals modified by letter codes that are difficult to remember. Second, it implies an orderly, linear pattern of lesion progression. This tends to be ambiguous, because it is not clear whether there is a single sequence of events during the progression of all lesions. We have therefore tried to devise a simpler classification scheme that is consistent with the AHA categories but is easier to use, able to deal with a wide array of morphological variations, and not overly burdened by mechanistic implications.   The current paradigm is based on the belief that type IV lesions, or “atheromas,” described by the AHA are stable because the fatty, necrotic core is contained by a smooth muscle cell–rich fibrous cap. Virchow’s analysis5 in 1858 pointed out that historically, the term “atheroma” refers to a dermal cyst (“Grutzbalg”), a fatty …


Diaphragm Atrophy and Contractile Dysfunction in a Murine Model of Pulmonary Hypertension

Abstract: Pulmonary hypertension (PH) causes loss of body weight and inspiratory (diaphragm) muscle dysfunction. A model of PH induced by drug (monocrotaline, MCT) has been extensively used in mice to examine the etiology of PH. However, it is unclear if PH induced by MCT in mice reproduces the loss of body weight and diaphragm muscle dysfunction seen in patients. This is a pre-requisite for widespread use of mice to examine mechanisms of cachexia and diaphragm abnormalities in PH. Thus, we measured body and soleus muscle weight, food intake, and diaphragm contractile properties in mice after 6-8 weeks of saline (control) or MCT (600 mg/kg) injections. Body weight progressively decreased in PH mice, while food intake was similar in both groups. PH decreased (P<0.05) diaphragm maximal isometric specific force, maximal shortening velocity, and peak power. Protein carbonyls in whole-diaphragm lysates and the abundance of select myofibrillar proteins were unchanged by PH. Our findings show diaphragm isometric and isotonic contractile abnormalities in a murine model of PH induced by MCT. Overall, the murine model of PH elicited by MCT mimics loss of body weight and diaphragm muscle weakness reported in PH patients.


Margination of white blood cells in microcapillary flow.

Abstract: Margination of white blood cells (WBCs) towards vessel walls is an essential precondition for their efficient adhesion to the vascular endothelium. We perform numerical simulations with a two-dimensional blood flow model to investigate the dependence of WBC margination on hydrodynamic interactions of blood cells with the vessel walls, as well as on their collective behavior and deformability. We find WBC margination to be optimal in intermediate ranges of red blood cell (RBC) volume fractions and flow rates, while, beyond these ranges, it is substantially attenuated. RBC aggregation enhances WBC margination, while WBC deformability reduces it. These results are combined in state diagrams, which identify WBC margination for a wide range of flow and cell suspension conditions.


Platelet glycoprotein IIb/IIIa inhibitors reduce mortality in diabetic patients with non-ST-segment-elevation acute coronary syndromes.

Abstract:
BACKGROUND Diabetes mellitus is a major risk factor for adverse outcomes after acute coronary syndromes (ACS). Because this disease may be associated with increased platelet aggregation, we investigated whether diabetic patients with ACS derive particular benefit from platelet glycoprotein (GP) IIb/IIIa receptor inhibition.
 METHODS AND RESULTS We performed a meta-analysis of the diabetic populations enrolled in the 6 large-scale platelet GP IIb/IIIa inhibitor ACS trials: PRISM, PRISM-PLUS, PARAGON A, PARAGON B, PURSUIT, and GUSTO IV. Among 6458 diabetic patients, platelet GP IIb/IIIa inhibition was associated with a significant mortality reduction at 30 days, from 6.2% to 4.6% (OR 0.74; 95% CI 0.59 to 0.92; P=0.007). Conversely, 23 072 nondiabetic patients had no survival benefit (3.0% versus 3.0%). The interaction between platelet GP IIb/IIIa inhibition and diabetic status was statistically significant (P=0.036). Among 1279 diabetic patients undergoing percutaneous coronary intervention (PCI) during index hospitalization, the use of these agents was associated with a mortality reduction at 30 days from 4.0% to 1.2% (OR 0.30; 95% CI 0.14 to 0.69; P=0.002).
 CONCLUSIONS This meta-analysis, including the entire large-scale trial experience of intravenous platelet GP IIb/IIIa inhibitors for the medical management of non-ST-segment-elevation ACS, shows that these agents may significantly reduce mortality at 30 days in diabetic patients. Although not based on a randomized assessment, the survival benefit appears to be of greater magnitude in patients undergoing PCI. Therefore, the use of platelet GP IIb/IIIa inhibitors should be strongly considered in diabetic patients with ACS.


The INO80 chromatin remodeling complex in transcription, replication and repair.

Abstract: The Ino80 ATPase is a member of the SNF2 family of ATPases and functions as an integral component of a multisubunit ATP-dependent chromatin remodeling complex. Although INO80 complexes from yeast and higher eukaryotes share a common core of conserved subunits, the complexes have diverged substantially during evolution and have acquired new subunits with apparently species-specific functions. Recent studies have shown that the INO80 complex contributes to a wide variety of chromatin-dependent nuclear transactions, including transcription, DNA repair and DNA replication.


ACAM2000™: The new smallpox vaccine for United States Strategic National Stockpile

Abstract: Smallpox was eradicated more than 30 years ago, but heightened concerns over bioterrorism have brought smallpox and smallpox vaccination back to the forefront. The previously licensed smallpox vaccine in the United States, Dryvax (Wyeth Laboratories, Inc.), was highly effective, but the supply was insufficient to vaccinate the entire current US population. Additionally, Dryvax had a questionable safety profile since it consisted of a pool of vaccinia virus strains with varying degrees of virulence, and was grown on the skin of calves, an outdated technique that poses an unnecessary risk of contamination. The US government has therefore recently supported development of an improved live vaccinia virus smallpox vaccine. This initiative has resulted in the development of ACAM2000 (Acambis, Inc.), a single plaque-purified vaccinia virus derivative of Dryvax, aseptically propagated in cell culture. Preclinical and clinical trials reported in 2008 demonstrated that ACAM2000 has comparable immunogenicity to that of Dryvax, and causes a similar frequency of adverse events. Furthermore, like Dryvax, ACAM2000 vaccination has been shown by careful cardiac screening to result in an unexpectedly high rate of myocarditis and pericarditis. ACAM2000 received US Food and Drug Administration (FDA) approval in August 2007, and replaced Dryvax for all smallpox vaccinations in February 2008. Currently, over 200 million doses of ACAM2000 have been produced for the US Strategic National Stockpile. This review of ACAM2000 addresses the production, characterization, clinical trials, and adverse events associated with this new smallpox vaccine.


Risk of malignant neoplasms in patients with pulmonary sarcoidosis.

Abstract:
BACKGROUND For over 20 years the association between sarcoidosis and malignancy, particularly lymphoma and lung cancer, has been disputed with misclassification being the major concern. The aim of the present study was to analyse the incidence of malignancies in a cohort of patients with sarcoidosis by linkage to a nationwide population based cancer register.
 METHODS The cohort comprised 254 patients followed for a median of 25 years until death, emigration, or 31 December 1992, whichever came first. The expected number of cancer cases was calculated using the annual age and sex specific cancer rates from the Danish Cancer Registry.
 RESULTS Thirty six cancers were registered, three of which were misclassified as sarcoidosis, leaving 33 cancers compared with 23 expected (standardised incidence ratio (SIR) = 1.4; 95% CI 0.99 to 2.0). Five lung cancers were observed compared with 2.5 expected, yielding an SIR of 2.0 (95% CI 0.7 to 4.7). There was no incidence of lymphoma and only one case of leukaemia. There was a significant excess number of pharyngeal cancers based on two cases (SIR = 15.4; 95% CI 1.7 to 56).
 CONCLUSIONS This study does not support the theory of an association between sarcoidosis and malignancy, and the main reason other studies have shown such an association is most likely to have been due to selection bias and misclassification.


Structure of the Guanine Nucleotide Exchange Factor Sec7 Domain of Human Arno and Analysis of the Interaction with ARF GTPase

Abstract: Sec7-related guanine nucleotide exchange factors (GEFs) initiate vesicle budding from the Golgi membrane surface by converting the GTPase ARF to a GTP-bound, membrane-associated form. Here we report the crystal structure of the catalytic Sec7 homology domain of Arno, a human GEF for ARF1, determined at 2.2 angstroms resolution. The Sec7 domain is an elongated, all-helical protein with a distinctive hydrophobic groove that is phylogenetically conserved. Structure-based mutagenesis identifies the groove and an adjacent conserved loop as the ARF-interacting surface. The sites of Sec7 domain interaction on ARF1 have subsequently been mapped, by protein footprinting experiments, to the switch 1 and switch 2 GTPase regions, leading to a model for the interaction between ARF GTPases and Sec7 domain exchange factors.


Brief Communication Repeated Cocaine Administration Increases Voltage-Sensitive Calcium Currents in Response to Membrane Depolarization in Medial Prefrontal Cortex Pyramidal Neurons

Abstract: The medial prefrontal cortex (mPFC) plays a critical role in cocaine addiction. However, evidence to elucidate how the mPFC is functionally involved in cocaine addiction remains incomplete. Recent studies have revealed that repeated cocaine administration induces various neuroadaptations in pyramidal mPFC neurons, including a reduction in voltage-gated K+ currents (VGKCs) and a possible increase in voltage-sensitive Ca2+ currents (I(Ca)). Here, we performed both current-clamp recordings in brain slices and voltage-clamp recordings in freshly dissociated cells to determine whether I(Ca) is altered in mPFC pyramidal neurons after chronic cocaine treatment with a short-term or long-term withdrawal. In addition, a critical role of VGKCs in regulating the generation of Ca2+ plateau potential was also studied in mPFC neurons. Repeated cocaine administration significantly prolonged the duration of evoked Ca2+ plateau potentials and increased the whole-cell I(Ca) in mPFC neurons after a 3 d withdrawal. Selective blockade of L-type Ca2+ channels by nifedipine not only significantly increased the threshold but also reduced the duration and amplitude of Ca2+ plateau potentials in both saline- and cocaine-withdrawn mPFC neurons. However, there was no significant difference in the increased threshold, reduced duration, and decreased amplitude of Ca2+ potentials between saline- and cocaine-withdrawn neurons after blockade of L-type Ca2+ channels. Moreover, an increase in amplitude was also observed, whereas the prolonged duration persisted, in Ca2+ potentials after 2-3 weeks of withdrawal. These findings indicate that chronic exposure to cocaine facilitates the responsiveness of I(Ca), particularly via the activated L-type Ca2+ channels, to excitatory stimuli in rat mPFC pyramidal neurons.


Locations of cerebral infarctions in tuberculous meningitis

Abstract: The locations of cerebral infarctions were studied in 14 patients with tuberculous meningitis (TBM) and 173 patients with noninflammatory ischemic stroke (IS). In patients with TBM, 75% of infarctions occurred in the “TB zone” supplied by medial striate and thalamoperforating arteries; only 11% occurred in the “IS zone” supplied by lateral striate, anterior choroidal and thalamogeniculate arteries. In patients with IS 29% of infarctions occurred in the IS zone, 29% in the subcortical white matter, and 24% in (or involving) the cerebral cortex. Only 11% occurred in the TB zone. Bilaterally symmetrical infarctions of the TB zone were common with TMB (71%) but rare with IS (5%).


TRP channels of intracellular membranes.

Abstract: Ion channels are classically understood to regulate the flux of ions across the plasma membrane in response to a variety of environmental and intracellular cues. Ion channels serve a number of functions in intracellular membranes as well. These channels may be temporarily localized to intracellular membranes as a function of their biosynthetic or secretory pathways, i.e., en route to their destination location. Intracellular membrane ion channels may also be located in the endocytic pathways, either being recycled back to the plasma membrane or targeted to the lysosome for degradation. Several channels do participate in intracellular signal transduction; the most well known example is the inositol 1,4,5-trisphosphate receptor (IP(3)R) in the endoplasmic reticulum. Some organellar intracellular membrane channels are required for the ionic homeostasis of their residing organelles. Several newly-discovered intracellular membrane Ca(2+) channels actually play active roles in membrane trafficking. Transient receptor potential (TRP) proteins are a superfamily (28 members in mammal) of Ca(2+)-permeable channels with diverse tissue distribution, subcellular localization, and physiological functions. Almost all mammalian TRP channels studied thus far, like their ancestor yeast TRP channel (TRPY1) that localizes to the vacuole compartment, are also (in addition to their plasma membrane localization) found to be localized to intracellular membranes. Accumulated evidence suggests that intracellularly-localized TRP channels actively participate in regulating membrane traffic, signal transduction, and vesicular ion homeostasis. This review aims to provide a summary of these recent works. The discussion will also be extended to the basic membrane and electrical properties of the TRP-residing compartments.


Single-Cell Expression Analyses during Cellular Reprogramming Reveal an Early Stochastic and a Late Hierarchic Phase

Abstract: During cellular reprogramming, only a small fraction of cells become induced pluripotent stem cells (iPSCs). Previous analyses of gene expression during reprogramming were based on populations of cells, impeding single-cell level identification of reprogramming events. We utilized two gene expression technologies to profile 48 genes in single cells at various stages during the reprogramming process. Analysis of early stages revealed considerable variation in gene expression between cells in contrast to late stages. Expression of Esrrb, Utf1, Lin28, and Dppa2 is a better predictor for cells to progress into iPSCs than expression of the previously suggested reprogramming markers Fbxo15, Fgf4, and Oct4. Stochastic gene expression early in reprogramming is followed by a late hierarchical phase with Sox2 being the upstream factor in a gene expression hierarchy. Finally, downstream factors derived from the late phase, which do not include Oct4, Sox2, Klf4, c-Myc, and Nanog, can activate the pluripotency circuitry.


Geographic distribution of community-acquired methicillin-resistant Staphylococcus aureus soft tissue infections.

Abstract:
PURPOSE The goal of this study is to look at the geographic growth patterns of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections in our local region and to determine if specific geographic areas are at increased risk.
 METHODS After Institution Review Board approval (132603-3), a retrospective chart review was conducted of 614 patients who underwent incision and drainage of an abscess by a single pediatric surgical practice from January 2004 to December 2008. In addition, previously published data from 195 patients who underwent incision and drainage of an abscess from January 2000 to December 2003 were reviewed.
 RESULTS The most commonly cultured organism found in the pediatric population undergoing incision and drainage was S aureus (n = 388), of which 258 (66%) were methicillin resistant. This is a 21% increase from the rate of MRSA cultures identified from 2000 to 2003. Geographic information system space-time analysis showed that a cluster of 14 MRSA cases was located within a 1.44-km radius between 2000 and 2003, and 5 separate clusters of more than 20 MRSA infection cases each were identified in 3 separate cities over the 8-year time span using geographic information system spatial analysis (P value = .001).
 CONCLUSION Methicillin-resistant S aureus has now become the most prevalent organism isolated from cultures of community-acquired abscesses requiring incision and drainage in the pediatric population in our local region. Significant clustering of MRSA infections has appeared in several different cities within our geographic region.


Treatment of spondyloarthropathy with 5-aminosalicylic acid (mesalazine): an open trial.

Abstract:
OBJECTIVE Ankylosing spondylitis (AS) and spondyloarthropathy (SpA) are inflammatory diseases of unknown etiology. Various exogenous and endogenous (inherited) factors play a role in their development. Sulfasalazine (SSZ) is generally accepted as a disease modifying drug in the treatment of AS and SpA. Which part of SSZ, 5-acetylsalicylic acid (5-ASA, mesalazine) or sulfapyridine (SP), is the effective moiety is unknown. As the bowel, colon, and the ileum play an important role in the development of AS and SpA, it may be possible that 5-ASA is the effective moiety, with a similar mode of action as in the treatment of inflammatory bowel disease. To determine the efficacy of 5-ASA an open pilot study was done in 2 groups of patients with SpA.   METHODS Twenty patients with SpA, who were taking SSZ, were switched to 5-ASA (Pentasa), and 19 patients with active SpA were treated with 5-ASA without previous administration of SSZ.
 RESULTS In the first group, 17 (85%) patients responded with respect to the physician global clinical assessment compared to the previous SSZ treatment period; whereas in the second patient group a statistically significant improvement was obtained in erythrocyte sedimentation rate.
 CONCLUSION The results support our hypothesis that 5-ASA might be the active moiety of SSZ in the treatment of SpA.


Convergence of 9-cis retinoic acid and peroxisome proliferator signalling pathways through heterodimer formation of their receptors

Abstract: PEROXISOMES are cytoplasmic organelles which are important in mammals in modulation of lipid homeostasis, including the metabolism of long-chain fatty acids and conversion of cholesterol to bile salts (reviewed in refs 1 and 2). Amphipathic carboxylates such as clofibric acid have been used in man as hypolipidaemic agents and in rodents they stimulate the proliferation of peroxisomes. These agents, termed peroxisome proliferators, and all-trans retinoic acid activate genes involved in peroxisomal-mediated β-oxidation of fatty acids1–4. Here we show that the receptor activated by peroxisome proliferators5 and the retinoid X receptor-α (ref. 6) form a heterodimer that activates acyl-CoA oxidase gene expression in response to either clofibric acid or the retinoid X receptor-α ligand, 9-cis retinoic acid, an all-trans retinoic acid metabolite7,8; simultaneous exposure to both activators results in a synergistic induction of gene expression. These data demonstrate the coupling of the peroxisome proliferator and retinoid signalling pathways and provide evidence for a physiological role for 9-cis retinoic acid in modulating lipid metabolism.


Exercise and the immune system: regulation, integration, and adaptation.

Abstract: Stress-induced immunological reactions to exercise have stimulated much research into stress immunology and neuroimmunology. It is suggested that exercise can be employed as a model of temporary immunosuppression that occurs after severe physical stress. The exercise-stress model can be easily manipulated experimentally and allows for the study of interactions between the nervous, the endocrine, and the immune systems. This review focuses on mechanisms underlying exercise-induced immune changes such as neuroendocrinological factors including catecholamines, growth hormone, cortisol, beta-endorphin, and sex steroids. The contribution of a metabolic link between skeletal muscles and the lymphoid system is also reviewed. The mechanisms of exercise-associated muscle damage and the initiation of the inflammatory cytokine cascade are discussed. Given that exercise modulates the immune system in healthy individuals, considerations of the clinical ramifications of exercise in the prevention of diseases for which the immune system has a role is of importance. Accordingly, drawing on the experimental, clinical, and epidemiological literature, we address the interactions between exercise and infectious diseases as well as exercise and neoplasia within the context of both aging and nutrition.


Bax translocation and mitochondrial fragmentation induced by Helicobacter pylori.

Abstract:
BACKGROUND AND AIMS Previous in vitro and in vivo studies have revealed an association between Helicobacter pylori infection and apoptosis in gastric epithelial cells. Although involvement of the Bcl-2 family of proteins as well as cytochrome c release has been demonstrated in H pylori induced cell death, the exact role of the mitochondria during this type of programmed cell death has not been fully elucidated. Therefore, we sought to determine whether or not Bax translocation and mitochondrial fragmentation occur on exposure of gastric epithelial cells to H pylori, resulting in cell death.
 METHODS Experiments were performed with human gastric adenocarcinoma (AGS) cells, AGS cells transfected with the HPV-E6 gene (which inactivates p53 function), AGS-neo cells (transfected with the backbone construct), mouse embryonic fibroblasts (MEFs), and p19(ARF) null (ARF(-/-)) MEFs. Cells were incubated with a cag positive H pylori strain for up to 24 hours, lysed, and cytoplasmic and mitochondrial membrane fractions were analysed by western blot for Bax translocation.
 RESULTS Bax translocation was detected in AGS, AGS-neo, and normal MEF cells after exposure to H pylori for three hours, but not in ARF(-/-) MEFs cells. Translocation of Bax after H pylori incubation was also detected in AGS-E6 cells (inactive p53 gene) but to a lesser degree than in AGS-neo cells. In parallel studies, the mitochondrial morphology of living cells infected with H pylori was assessed by confocal microscopy. Mitochondrial fragmentation was detectable after 10 hours of H pylori incubation with AGS cells and after seven hours with MEF cells. In wild-type MEFs, mitochondrial fragmentation was significantly increased in comparison with ARF null MEFs (43% v 10.4%, respectively). Furthermore, mitochondrial depolarisation and caspase-3 activity were initiated within four hours in cells incubated with H pylori, and these events were inhibited by forced expression of Bcl-2.
 CONCLUSIONS These data suggest that during H pylori induced apoptosis, Bax translocates to the mitochondria which subsequently undergo depolarisation and profound fragmentation. Functional ARF and p53 proteins may play an important role in H pylori induced mitochondrial modification.


Deregulation of Scribble Promotes Mammary Tumorigenesis and Reveals a Role for Cell Polarity in Carcinoma

Abstract: Loss of cell polarity proteins such as Scribble induces neoplasia in Drosophila by promoting uncontrolled proliferation. In mammals, the role that polarity proteins play during tumorigenesis is not well understood. Here, we demonstrate that depletion of Scribble in mammary epithelia disrupts cell polarity, blocks three-dimensional morphogenesis, inhibits apoptosis, and induces dysplasia in vivo that progress to tumors after long latency. Loss of Scribble cooperates with oncogenes such as c-myc to transform epithelial cells and induce tumors in vivo by blocking activation of an apoptosis pathway. Like depletion, mislocalization of Scribble from cell-cell junction was sufficient to promote cell transformation. Interestingly, spontaneous mammary tumors in mice and humans possess both downregulated and mislocalized Scribble. Thus, we demonstrate that scribble inhibits breast cancer formation and that deregulation of polarity pathways promotes dysplastic and neoplastic growth in mammals by disrupting morphogenesis and inhibiting cell death.


The Polymeal: a more natural, safer, and probably tastier (than the Polypill) strategy to reduce cardiovascular disease by more than 75%.

Abstract:
OBJECTIVE Although the Polypill concept (proposed in 2003) is promising in terms of benefits for cardiovascular risk management, the potential costs and adverse effects are its main pitfalls. The objective of this study was to identify a tastier and safer alternative to the Polypill: the Polymeal.
 METHODS Data on the ingredients of the Polymeal were taken from the literature. The evidence based recipe included wine, fish, dark chocolate, fruits, vegetables, garlic, and almonds. Data from the Framingham heart study and the Framingham offspring study were used to build life tables to model the benefits of the Polymeal in the general population from age 50, assuming multiplicative correlations.
 RESULTS Combining the ingredients of the Polymeal would reduce cardiovascular disease events by 76%. For men, taking the Polymeal daily represented an increase in total life expectancy of 6.6 years, an increase in life expectancy free from cardiovascular disease of 9.0 years, and a decrease in life expectancy with cardiovascular disease of 2.4 years. The corresponding differences for women were 4.8, 8.1, and 3.3 years.
 CONCLUSION The Polymeal promises to be an effective, non-pharmacological, safe, cheap, and tasty alternative to reduce cardiovascular morbidity and increase life expectancy in the general population.


Contemporary type 1 diabetes pregnancy outcomes: impact of obesity and glycaemic control.

Abstract:
OBJECTIVE To compare contemporary pregnancy outcomes in women with and without type 1 diabetes, and to examine the effects of obesity and glycaemic control on these outcomes.
 DESIGN AND SETTING Historical cohort study in a specialist diabetes and maternity network in Victoria.
 PARTICIPANTS All singleton births (at least 20 weeks' gestation), 2010-2013, were analysed: 107 pregnancies to women with type 1 diabetes and 27 075 pregnancies to women without diabetes. Women with type 2 diabetes or gestational diabetes were excluded.
 METHODS Data were extracted from the Birthing Outcomes System database; associations between type 1 diabetes and pregnancy outcomes were analysed by multivariable regression.
 MAIN OUTCOME MEASURES Mode of birth; maternal and neonatal outcomes.
 RESULTS The mean body mass index was higher for women with type 1 diabetes than for women without diabetes (mean, 27.3 kg/m(2) [SD, 5.0] v 25.7 kg/m(2) [SD, 5.9]; P = 0.01); the median gestation period for their babies was shorter (median, 37.3 weeks [IQR, 34.6-38.1] v 39.4 weeks [IQR, 38.4-40.4]; P < 0.001) and they were more likely to be large for gestational age (LGA) (adjusted odds ratio [aOR], 7.9; 95% CI, 5.3-11.8). Women with type 1 diabetes were more likely to have had labour induced (aOR, 3.0; 95% CI, 2.0-4.5), a caesarean delivery (aOR, 4.6; 95% CI, 3.1-7.0), or a pre-term birth (aOR, 6.7; 95% CI, 4.5-10.0); their babies were more likely to have shoulder dystocia (aOR, 8.2; 95% CI, 3.6-18.7), hypoglycaemia (aOR, 10.3; 95% CI, 6.8-15.6), jaundice (aOR, 5.1; 95% CI, 3.3-7.7), respiratory distress (aOR, 2.5; 95% CI, 1.4-4.4) or to suffer perinatal death (aOR, 4.3; 95% CI, 1.9-9.9). In women with type 1 diabetes, greater obesity was associated with increased odds for an LGA baby or congenital malformation, and increased HbA1c levels were associated with pre-term birth and perinatal death.
 CONCLUSION Women with type 1 diabetes, even when managed in a specialist setting, still experience adverse obstetric and neonatal outcomes. Poor glycaemic control is not wholly responsible for adverse outcomes, reinforcing the importance of other risk factors, such as obesity and weight gain.


Antibody-Based HIV-1 Vaccines: Recent Developments and Future Directions

Abstract: The Global HIV Vaccine Enterprise convened a two-day workshop in May of 2007 to discuss humoral immune responses to HIV and approaches to design vaccines that induce viral neutralizing and other potentially protective antibody responses. The goals of this workshop were to identify key scientific issues, gaps, and opportunities that have emerged since the Enterprise Strategic Plan was first published in 2005 [1], and to make recommendations that Enterprise stakeholders can use to plan new activities.     Most effective viral vaccines work, at least in part, by generating antibodies that inactivate or neutralize the invading virus, and the existing data strongly suggest that an optimally effective HIV-1 vaccine should elicit potent antiviral neutralizing antibodies. However, unlike acute viral pathogens, HIV-1 chronically replicates in the host and evades the antibody response. This immune evasion, along with the large genetic variation among HIV-1 strains worldwide, has posed major obstacles to vaccine development. Current HIV vaccine candidates do not elicit neutralizing antibodies against most circulating virus strains, and thus the induction of a protective antibody response remains a major priority for HIV-1 vaccine development. For an antibody-based HIV-1 vaccine, progress in vaccine design is generally gauged by in vitro assays that measure the ability of vaccine-induced antibodies to neutralize a broad spectrum of viral isolates representing the major genetic subtypes (clades) of HIV-1 [2]. Although it is not known what magnitude and breadth of neutralization will predict protection in vaccine recipients, it is clear that current vaccine immunogens elicit antibodies that neutralize only a minority of circulating isolates. Thus, much progress needs to be made in this area. Also, though virus neutralization is considered a critical benchmark for a vaccine, this may not be the only benchmark for predicting success with antibody-based HIV-1 vaccine immunogens.     The main targets for neutralizing antibodies to HIV-1 are the surface gp120 and trans-membrane gp41 envelope glycoproteins (Env) that mediate receptor and coreceptor binding and the subsequent membrane fusion events that allow the virus to gain entry into cells [3]. Antibodies neutralize the virus by binding these viral spikes and blocking virus entry into susceptible cells, such as CD4+ T cells [4,5]. In order to chronically replicate in the host, the virus exploits several mechanisms to shield itself against antibody recognition, including a dense outer coating of sugar molecules (N-linked glycans) and the strategic positioning of cysteine–cysteine loop structures on the gp120 molecule [6–8]. These shielding mechanisms, although highly effective, have vulnerabilities imposed by fitness constraints. Information on the precise location and molecular structure of these vulnerable regions could be valuable for the rational design of improved vaccine immunogens.     Participants in the workshop identified four areas that, if given proper attention, could provide key information that would bring the field closer to an effective antibody-based HIV-1 vaccine: (1) structure-assisted immunogen design, (2) role of Fc receptors and complement, (3) assay standardization and validation, and (4) immunoregulation of B cell responses.


PD-L1 expression in human cancers and its association with clinical outcomes

Abstract: PD-L1 is an immunoinhibitory molecule that suppresses the activation of T cells, leading to the progression of tumors. Overexpression of PD-L1 in cancers such as gastric cancer, hepatocellular carcinoma, renal cell carcinoma, esophageal cancer, pancreatic cancer, ovarian cancer, and bladder cancer is associated with poor clinical outcomes. In contrast, PD-L1 expression correlates with better clinical outcomes in breast cancer and merkel cell carcinoma. The prognostic value of PD-L1 expression in lung cancer, colorectal cancer, and melanoma is controversial. Blocking antibodies that target PD-1 and PD-L1 have achieved remarkable response rates in cancer patients who have PD-L1-overexpressing tumors. However, using PD-L1 as an exclusive predictive biomarker for cancer immunotherapy is questionable due to the low accuracy of PD-L1 immunohistochemistry staining. Factors that affect the accuracy of PD-L1 immunohistochemistry staining are as follows. First, antibodies used in different studies have different sensitivity. Second, in different studies, the cut-off value of PD-L1 staining positivity is different. Third, PD-L1 expression in tumors is not uniform, and sampling time and location may affect the results of PD-L1 staining. Therefore, better understanding of tumor microenvironment and use of other biomarkers such as gene marker and combined index are necessary to better identify patients who will benefit from PD-1/PD-L1 checkpoint blockade therapy.


Centrosome aberrations: cause or consequence of cancer progression?

Abstract: Many human tumours show centrosome aberrations, indicating an underlying deregulation of centrosome structure, duplication or segregation. Centrosomes organize microtubule arrays throughout the cell cycle, thereby influencing both tissue architecture and the accuracy of chromosome segregation. But what are the origins of centrosomal abnormalities in tumours, and what impact do they have on the generation of invasive, genetically unbalanced cells during cancer progression?


Early lymphocyte expansion is severely impaired in interleukin 7 receptor-deficient mice

Abstract: Interleukin 7 (IL-7) stimulates the proliferation of B cell progenitors, thymocytes, and mature T cells through an interaction with a high affinity receptor (IL-7R) belonging to the hematopoietin receptor superfamily. We have further addressed the role of IL-7 and its receptor during B and T cell development by generating mice genetically deficient in IL-7R. Mutant mice display a profound reduction in thymic and peripheral lymphoid cellularity. Analyses of lymphoid progenitor populations in IL-7R-deficient mice define precisely those developmental stages affected by the mutation and reveal a critical role for IL-7R during early lymphoid development. Significantly, these studies indicate that the phase of thymocyte expansion occurring before the onset of T cell receptor gene rearrangement is critically dependent upon, and mediated by the high affinity receptor for IL-7.


The role of red cell distribution width in the prognosis of patients with gastric cancer.

Abstract:
BACKGROUND Although the red cell distribution width (RDW) has been reported as a reliable predictor of prognosis in several types of cancer, to our knowledge the prognostic value of RDW in gastric carcinoma has not been studied, so far.
 OBJECTIVE We aimed to investigate the role of red cell distribution width (RDW) in predicting prognosis in gastric cancer patients.
 METHODS All gastric cancer patients who underwent curative surgery (n= 172, 110M/62F) over a five-year study period were evaluated. Data on demographics, preoperative RDW levels, tumor characteristics (early stage: I and II, advanced stage: IIIA-B-C), disease-free (DFS) and overall survival (OS) were retrospectively reviewed. Patients were classified as high RDW group (RDW ≥ 16, n= 62) or low RDW group (RDW < 16, n= 110).
 RESULTS Overall mortality and postoperative 60-day mortality in both groups were 55% and 14%, respectively. A borderline significant association between RDW (0.063) and mortality was noted. Preoperative RDW levels were significantly higher in patients with short-term mortality (17.9 ± 4.3 vs. 16 ± 3.2, p= 0.015). In high RDW group, the incidence of advanced gastric cancer was significantly higher (75 vs. 51%, p= 0.002), whereas DFS (0.035) and OS (p= 0.04) were lower.
 CONCLUSION The frequency of advanced cancer was high in patients with high RDWvalues. High RDW values were strongly associated with short-term mortality although only a borderline relationship with overall survival was observed.


DNA replication is required To elicit cellular responses to psoralen-induced DNA interstrand cross-links.

Abstract: Following introduction of DNA interstrand cross-links (ICLs), mammalian cells display chromosome breakage or cell cycle delay with a 4N DNA content. To further understand the nature of the delay, previously described as a G(2)/M arrest, we developed a protocol to generate ICLs during specific intervals of the cell cycle. Synchronous populations of G(1), S, and G(2) cells were treated with photoactivated 4'-hydroxymethyl-4,5',8-trimethylpsoralen (HMT) and scored for normal passage into mitosis. In contrast to what was found for ionizing radiation, ICLs introduced during G(2) did not result in a G(2)/M arrest, mitotic arrest, or chromosome breakage. Rather, subsequent passage through S phase was required to trigger both chromosome breakage and arrest in the next cell cycle. Similarly, ICLs introduced during G(1) did not cause a G(1)/S arrest. We conclude that DNA replication is required to elicit the cellular responses of cell cycle arrest and genomic instability after psoralen-induced ICLs. In primary human fibroblasts, the 4N DNA content cell cycle arrest triggered by ICLs was long lasting but reversible. Kinetic analysis suggested that these cells could remove up to approximately 2,500 ICLs/genome at an average rate of 11 ICLs/genome/h.


DNA methylation and healthy human aging

Abstract: The process of aging results in a host of changes at the cellular and molecular levels, which include senescence, telomere shortening, and changes in gene expression. Epigenetic patterns also change over the lifespan, suggesting that epigenetic changes may constitute an important component of the aging process. The epigenetic mark that has been most highly studied is DNA methylation, the presence of methyl groups at CpG dinucleotides. These dinucleotides are often located near gene promoters and associate with gene expression levels. Early studies indicated that global levels of DNA methylation increase over the first few years of life and then decrease beginning in late adulthood. Recently, with the advent of microarray and next-generation sequencing technologies, increases in variability of DNA methylation with age have been observed, and a number of site-specific patterns have been identified. It has also been shown that certain CpG sites are highly associated with age, to the extent that prediction models using a small number of these sites can accurately predict the chronological age of the donor. Together, these observations point to the existence of two phenomena that both contribute to age-related DNA methylation changes: epigenetic drift and the epigenetic clock. In this review, we focus on healthy human aging throughout the lifetime and discuss the dynamics of DNA methylation as well as how interactions between the genome, environment, and the epigenome influence aging rates. We also discuss the impact of determining 'epigenetic age' for human health and outline some important caveats to existing and future studies.


Acquired EGFR C797S mutation mediates resistance to AZD9291 in non–small cell lung cancer harboring EGFR T790M

Abstract: Here we studied cell-free plasma DNA (cfDNA) collected from subjects with advanced lung cancer whose tumors had developed resistance to the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) AZD9291. We first performed next-generation sequencing of cfDNA from seven subjects and detected an acquired EGFR C797S mutation in one; expression of this mutant EGFR construct in a cell line rendered it resistant to AZD9291. We then performed droplet digital PCR on serial cfDNA specimens collected from 15 AZD9291-treated subjects. All were positive for the T790M mutation before treatment, but upon developing AZD9291 resistance three molecular subtypes emerged: six cases acquired the C797S mutation, five cases maintained the T790M mutation but did not acquire the C797S mutation and four cases lost the T790M mutation despite the presence of the underlying EGFR activating mutation. Our findings provide insight into the diversity of mechanisms through which tumors acquire resistance to AZD9291 and highlight the need for therapies that are able to overcome resistance mediated by the EGFR C797S mutation.


Nuclear RNAi maintains heritable gene silencing in Caenorhabditis elegans.

Abstract: RNA interference (RNAi) is heritable in Caenorhabditis elegans; the progeny of C. elegans exposed to dsRNA inherit the ability to silence genes that were targeted by RNAi in the previous generation. Here we investigate the mechanism of RNAi inheritance in C. elegans. We show that exposure of animals to dsRNA results in the heritable expression of siRNAs and the heritable deposition of histone 3 lysine 9 methylation (H3K9me) marks in progeny. siRNAs are detectable before the appearance of H3K9me marks, suggesting that chromatin marks are not directly inherited but, rather, reestablished in inheriting progeny. Interestingly, H3K9me marks appear more prominently in inheriting progeny than in animals directly exposed to dsRNA, suggesting that germ-line transmission of silencing signals may enhance the efficiency of siRNA-directed H3K9me. Finally, we show that the nuclear RNAi (Nrde) pathway maintains heritable RNAi silencing in C. elegans. The Argonaute (Ago) NRDE-3 associates with heritable siRNAs and, acting in conjunction with the nuclear RNAi factors NRDE-1, NRDE-2, and NRDE-4, promotes siRNA expression in inheriting progeny. These results demonstrate that siRNA expression is heritable in C. elegans and define an RNAi pathway that promotes the maintenance of RNAi silencing and siRNA expression in the progeny of animals exposed to dsRNA.


The M/GP5 Glycoprotein Complex of Porcine Reproductive and Respiratory Syndrome Virus Binds the Sialoadhesin Receptor in a Sialic Acid-Dependent Manner

Abstract: The porcine reproductive and respiratory syndrome virus (PRRSV) is a major threat to swine health worldwide and is considered the most significant viral disease in the swine industry today. In past years, studies on the entry of the virus into its host cell have led to the identification of a number of essential virus receptors and entry mediators. However, viral counterparts for these molecules have remained elusive and this has made rational development of new generation vaccines impossible. The main objective of this study was to identify the viral counterparts for sialoadhesin, a crucial PRRSV receptor on macrophages. For this purpose, a soluble form of sialoadhesin was constructed and validated. The soluble sialoadhesin could bind PRRSV in a sialic acid-dependent manner and could neutralize PRRSV infection of macrophages, thereby confirming the role of sialoadhesin as an essential PRRSV receptor on macrophages. Although sialic acids are present on the GP(3), GP(4) and GP(5) envelope glycoproteins, only the M/GP(5) glycoprotein complex of PRRSV was identified as a ligand for sialoadhesin. The interaction was found to be dependent on the sialic acid binding capacity of sialoadhesin and on the presence of sialic acids on GP(5). These findings not only contribute to a better understanding of PRRSV biology, but the knowledge and tools generated in this study also hold the key to the development of a new generation of PRRSV vaccines.


Genome-wide association analyses in East Asians identify new susceptibility loci for colorectal cancer

Abstract: To identify new genetic factors for colorectal cancer (CRC), we conducted a                 genome-wide association study in east Asians. By analyzing genome-wide data in 2,098                 cases and 5,749 controls, we selected 64 promising SNPs for replication in an                 independent set of samples, including up to 5,358 cases and 5,922 controls. We                 identified four SNPs with association P values of 8.58 ×                     10(-7) to 3.77 × 10(-10)                 in the combined analysis of all east Asian samples. Three of the four were                 replicated in a study conducted in 26,060 individuals of European descent, with                 combined P values of 1.22 × 10(-10) for                 rs647161 (5q31.1), 6.64 × 10(-9) for rs2423279                 (20p12.3) and 3.06 × 10(-8) for rs10774214                 (12p13.32 near the CCND2 gene), derived from meta-analysis of data from both                 east Asian and European-ancestry populations. This study identified three new CRC                 susceptibility loci and provides additional insight into the genetics and biology of                 CRC.


Roles of histone acetylation and chromatin remodeling factor in a meiotic recombination hotspot.

Abstract: Histone acetyltransferases (HATs) and ATP-dependent chromatin remodeling factors (ADCRs) are involved in selective gene regulation via modulation of local chromatin configuration. Activation of the recombination hotspot ade6-M26 of Schizosaccharomyces pombe is mediated by a cAMP responsive element (CRE)-like sequence, M26, and a heterodimeric ATF/CREB transcription factor, Atf1.Pcr1. Chromatin remodeling occurs meiotically around M26. We examined the roles of HATs and ADCRs in chromatin remodeling around M26. Histones H3 and H4 around M26 were hyperacetylated in an M26- and Atf1-dependent manner early in meiosis. SpGcn5, the S. pombe homolog of Gcn5p, was required for the majority of histone H3 acetylation around M26 in vivo. Deletion of gcn5+ caused a significant delay in chromatin remodeling but only partial reduction of M26 meiotic recombination frequency. The snf22+ (a Swi2/Snf2-ADCR homologue) deletion and snf22+ gcn5+ double deletion abolished chromatin remodeling and significant reduction of meiotic recombination around M26. These results suggest that HATs and ADCRs cooperatively alter local chromatin structure, as in selective transcription activation, to activate meiotic recombination at M26 in a site-specific manner.


Radioiodine treatment of multinodular non-toxic goitre.

Abstract:
OBJECTIVE To investigate the long term effect of radioactive iodine on thyroid function and size in patients with non-toxic multinodular goitre.
 DESIGN Consecutive patients with multinodular non-toxic goitre selected for radioactive iodine treatment and followed for a minimum of 12 months (median 48 months) after an intended dose of 3.7 MBq/g thyroid tissue corrected to a 100% uptake of iodine-131 in 24 hours.
 PATIENTS 69 patients with a growing multinodular non-toxic goitre causing local compression symptoms or cosmetic inconveniences. The treatment was chosen because of a high operative risk, previous thyroidectomy, or refusal to be operated on.
 MAIN OUTCOME MEASUREMENTS Standard thyroid function variables and ultrasonically determined thyroid volume before treatment as well as 1, 2, 3, 6, and 12 months after treatment and then once a year.
 RESULTS 56 patients were treated with a single dose of 131I, 12 with two doses, and one with four doses. In 45 patients treated with one dose and remaining euthyroid the median thyroid volume was reduced from 73 (interquartile range 50-106) ml to 29 (23-48) ml at 24 months in the 39 patients in whom this was measured during follow up. The median reduction was 40 (22-48) ml (60% reduction, p < 0.0001), half of which occurred within three months. Patients treated with two doses as well as those developing hypothyroidism and hyperthyroidism had a significant reduction in thyroid volume. Eleven patients developed hypothyroidism (cumulative five year risk 22%, 95% confidence interval 4.8% to 38.4%). Side effects were few: three cases of hyperthyroidism and two cases of radiation thyroiditis. Only one patient was dissatisfied with the result; she was referred for operation six months after treatment.
 CONCLUSIONS A substantial reduction in thyroid volume accompanied by a low incidence of hypothyroidism and few side effects makes the use of radioactive iodine an attractive alternative to surgery in selected cases of non-toxic multinodular goitre.


Sugar-sweetened beverages, weight gain, and incidence of type 2 diabetes in young and middle-aged women.

Abstract:
CONTEXT Sugar-sweetened beverages like soft drinks and fruit punches contain large amounts of readily absorbable sugars and may contribute to weight gain and an increased risk of type 2 diabetes, but these relationships have been minimally addressed in adults.
 OBJECTIVE To examine the association between consumption of sugar-sweetened beverages and weight change and risk of type 2 diabetes in women.
 DESIGN, SETTING, AND PARTICIPANTS Prospective cohort analyses conducted from 1991 to 1999 among women in the Nurses' Health Study II. The diabetes analysis included 91,249 women free of diabetes and other major chronic diseases at baseline in 1991. The weight change analysis included 51,603 women for whom complete dietary information and body weight were ascertained in 1991, 1995, and 1999. We identified 741 incident cases of confirmed type 2 diabetes during 716,300 person-years of follow-up.
 MAIN OUTCOME MEASURES Weight gain and incidence of type 2 diabetes.
 RESULTS Those with stable consumption patterns had no difference in weight gain, but weight gain over a 4-year period was highest among women who increased their sugar-sweetened soft drink consumption from 1 or fewer drinks per week to 1 or more drinks per day (multivariate-adjusted means, 4.69 kg for 1991 to 1995 and 4.20 kg for 1995 to 1999) and was smallest among women who decreased their intake (1.34 and 0.15 kg for the 2 periods, respectively) after adjusting for lifestyle and dietary confounders. Increased consumption of fruit punch was also associated with greater weight gain compared with decreased consumption. After adjustment for potential confounders, women consuming 1 or more sugar-sweetened soft drinks per day had a relative risk [RR] of type 2 diabetes of 1.83 (95% confidence interval [CI], 1.42-2.36; P<.001 for trend) compared with those who consumed less than 1 of these beverages per month. Similarly, consumption of fruit punch was associated with increased diabetes risk (RR for > or =1 drink per day compared with <1 drink per month, 2.00; 95% CI, 1.33-3.03; P =.001).
 CONCLUSION Higher consumption of sugar-sweetened beverages is associated with a greater magnitude of weight gain and an increased risk for development of type 2 diabetes in women, possibly by providing excessive calories and large amounts of rapidly absorbable sugars.


Pancreatic stellate cells: partners in crime with pancreatic cancer cells.

Abstract: Pancreatic stellate cells (PSC) produce the stromal reaction in pancreatic cancer, but their role in cancer progression is not fully elucidated. We examined the influence of PSCs on pancreatic cancer growth using (a) an orthotopic model of pancreatic cancer and (b) cultured human PSCs (hPSC) and human pancreatic cancer cell lines MiaPaCa-2 and Panc-1. Athymic mice received an intrapancreatic injection of saline, hPSCs, MiaPaCa-2 cells, or hPSCs + MiaPaCa-2. After 7 weeks, tumor size, metastases, and tumor histology were assessed. In vitro studies assessed the effect of cancer cell secretions on PSC migration and the effect of hPSC secretions on cancer cell proliferation, apoptosis, and migration. Possible mediators of the effects of hPSC secretions on cancer cell proliferation were examined using neutralizing antibodies. Compared with mice receiving MiaPaCa-2 cells alone, mice injected with hPSCs + MiaPaCa-2 exhibited (a) increased tumor size and regional and distant metastasis, (b) fibrotic bands (desmoplasia) containing activated PSCs within tumors, and (c) increased tumor cell numbers. In vitro studies showed that, in the presence of pancreatic cancer cells, PSC migration was significantly increased. Furthermore, hPSC secretions induced the proliferation and migration, but inhibited the apoptosis, of MiaPaCa-2 and Panc-1 cells. The proliferative effect of hPSC secretions on pancreatic cancer cells was inhibited in the presence of neutralizing antibody to platelet-derived growth factor. Our studies indicate a significant interaction between pancreatic cancer cells and stromal cells (PSCs) and imply that pancreatic cancer cells recruit stromal cells to establish an environment that promotes cancer progression.


Behavioral characterization of neuropeptide Y knockout mice.

Abstract: An extensive behavioral characterization was conducted with mice lacking the gene for neuropeptide Y (NPY) including response to 24 and 48 h fast and challenge with small molecule antagonists of NPY receptors implicated in mediating the feeding effects of NPY (i.e., Y1 and Y5). In addition, wildtype (WT) and NPY knockout (KO) mice were tested in locomotor monitors, elevated plus maze, inhibitory avoidance, acoustic startle, prepulse inhibition, and hot plate assays. One of the major findings was that the NPY KO mice have a reduced food intake relative to WT controls in response to fasting. Also, based on data from the behavioral models, the NPY KO mice may have an anxiogenic-like phenotype, and appear to be hypoalgesic in the hot plate paradigm. The data from these studies provide further evidence of involvement of NPY in energy balance, anxiety, and possibly nociception.


Acute myopericarditis after multiple vaccinations in an adolescent: case report and review of the literature.

Abstract: We report a case of postvaccination acute myopericarditis in an adolescent. The patient presented with acute chest pain, diffuse ST-segment elevation, and elevated cardiac enzyme levels. Cardiac MRI was consistent with acute myocarditis. He recovered within a few days with nonsteroidal antiinflammatory treatment and remains clinically stable, with improvement of MRI findings at the 10-week follow-up. Postvaccination cases of myopericarditis reported in the pediatric literature are also reviewed.


Cardiovascular diseases in Chinese, Malays, and Indians in Singapore. I. Differences in mortality.

Abstract:
STUDY OBJECTIVE The aim of the study was to analyse differences in mortality from the main cardiovascular diseases (ischaemic heart disease, hypertensive disease, and cerebrovascular disease) among Chinese, Malays, and Indians in Singapore.
 DESIGN The study was a survey using national death registration data in Singapore for the five years 1980 to 1984. The underlying cause of death, coded according to the ninth revision of the International Classification of Diseases, was taken for the analyses.
 SETTING The study was confined to the independent island state of Singapore, population 2.53 million (Chinese 76.5%, Malays 14.8%, Indians 6.4%, Others 2.3%). Death registration is thought to be complete.    SUBJECTS All registered deaths in the age range 30-69 years during the study period were analysed by ethnic group.
 MEASUREMENT AND MAIN RESULTS Indians had higher mortality from ischaemic heart disease than the other ethnic groups in both sexes, with age-standardised relative risks of Indian v Chinese (males 3.8, females 3.4), Indian v Malay (males 1.9, females 1.6), and Malay v Chinese (males 2.0, females 2.2). The excess mortality in Indians declined with age. For hypertensive disease Malays had the highest mortality, with age-standardised relative risks of Malay v Chinese (males 3.4, females 4.4), Malay v Indian (males 2.0, females 2.5), and Indian v Chinese (males 1.6, females 1.6). For cerebrovascular disease there was little ethnic difference except for lower rates in Chinese females, with age-standardised relative risks of Malay v Chinese (males 1.1, females 1.9), Malay v Indian (males 1.0, females 1.1), and Indian v Chinese (males 1.1, females 1.7).
 CONCLUSIONS There are significant differences in mortality from the three main cardiovascular diseases in the different ethnic groups in Singapore.


Two sequence motifs from HIF-1alpha bind to the DNA-binding site of p53.

Abstract: There is evidence that hypoxia-inducible factor-1alpha (HIF-1alpha) interacts with the tumor suppressor p53. To characterize the putative interaction, we mapped the binding of the core domain of p53 (p53c) to an array of immobilized HIF-1alpha-derived peptides and found two peptide-sequence motifs that bound to p53c with micromolar affinity in solution. One sequence was adjacent to and the other coincided with the two proline residues of the oxygen-dependent degradation domain (P402 and P564) that act as switches for the oxygen-dependent regulation of HIF-1alpha. The binding affinity was independent of the hydroxylation state of P564. We found from NMR spectroscopy that these sequence motifs bind to the DNA-binding site of p53c. Because the two sequences are homologous and separated by 120 residues, and one is in a largely unstructured transactivation domain, we speculate that each sequence motif in HIF-1alpha binds to a different subunit of the p53 tetramer, leading to very tight binding. The binding data support the proposal that p53 provides a route for the degradation in hypoxic tumor cells of HIF-1alpha that is not hydroxylated at the two proline residues.


Knowledge and use of secondary contraception among patients requesting termination of pregnancy.

Abstract: The results of a survey of 769 patients attending the St. James's University Fertility Control Clinic, England, for abortion services showed that patients seeing general practitioners were less knowledgeable than those attending specialist clinics. There was a demonstrated need for counseling on pill and condom use and protection against sexually transmitted diseases. Knowledge of postcoital methods was also found to be lacking. The survey was conducted between April 1, 1991, and January 31, 1992. Respondents included minorities such as Afro-Caribbean (8%) and Asian (9%). 307 of the cases were using a less effective form of contraception at the time of conception, usually a change from the pill to condoms. Of the 171 people reporting failure of contraception, 93 noted a split or leaking condom; 13, a condom falling off during intercourse; 32, inconsistent use of condoms;l 32, forgetting to take contraceptive pills or using antibiotics with the pill; and 1, a late injection of medroxyprogesterone acetate. 45 of the 309 people who had conceived while using condoms recognized a potential condom failure, and only 20 attempted any emergency contraceptive method such as the postcoital pill. Only 30% of the 171 patients with recognized condom failure and 12% of the 210 who had not used any contraception had adequate knowledge of the existence, timing, and source of postcoital pills; i.e., 20% of 381. Only 2% of the 171 nd 2% of the 381 patients, had knowledge of postcoital insertion of an intrauterine contraceptive device. Given the choice between and unplanned pregnancy and postcoital contraceptive, most (718 out of 769) preferred using postcoital contraception. Contraceptive information was given to 501 by a general practitioner, to 102 by a community family planning clinic, and 163 had no medical advice. There was a range of knowledge of postcoital contraceptive methods. Knowledge of how to deal with forgotten pills, severe vomiting, severe diarrhea, and concurrent antibiotic treatment among the 422 patients who had ever used the combined pill also was variable. 19% of the 372 patients treated by general practitioners knew 4 correct answers, but 50% of the 50 patients in community family planning clinics answered correctly 4 times. Differences could not be explained by other demographic characteristics.


Long tandem arrays of complex repeat units in Chironomus telomeres.

Abstract: A cloned 340-bp DNA fragment excised by EcoRI from the Chironomus pallividittatus genome has been localized to the telomeres by in situ hybridization as well as to connectives between telomeres. No hybridization was observed in other regions of the chromosomes. Another cloned EcoRI fragment, 525 bp long has also been studied. This represents a partial duplication of the 340-bp sequence. Genomic blot hybridization experiments show that the 340-bp sequence is a representative monomeric unit of tandemly repeated arrays which account for 1.2% of the Chironomus genome, on average 300 kb per telomere. The repeat unit contains two types of subrepeats each present twice per repeat unit. Northern blot hybridization experiments show that the telomere-associated sequences are transcribed into a discrete RNA species approximately 20 kb in size. The evolution of this telomere-associated DNA is discussed.


Parallel processing in the mammalian retina

Abstract: Our eyes send different 'images' of the outside world to the brain — an image of contours (line drawing), a colour image (watercolour painting) or an image of moving objects (movie). This is commonly referred to as parallel processing, and starts as early as the first synapse of the retina, the cone pedicle. Here, the molecular composition of the transmitter receptors of the postsynaptic neurons defines which images are transferred to the inner retina. Within the second synaptic layer — the inner plexiform layer — circuits that involve complex inhibitory and excitatory interactions represent filters that select 'what the eye tells the brain'.


Association between folate intake from different food sources in Norway and homocysteine status in a dietary intervention among young male adults.

Abstract: The aim of the present investigation was to study the effect of a dietary intervention which combined nutrition information with increased availability of vegetables, fruits and wholegrain bread. The effect of the intervention was determined by changes in the intake of vegetables, fruits, wholegrain bread and estimated nutrients. Furthermore, the study investigated whether changes in relative contribution from different food sources of folate were related to changes in the concentration of plasma total homocysteine (p-tHcy). The 5-month intervention study included 376 male recruits from the Norwegian National Guard, Vaernes (intervention group) and 105 male recruits from the Norwegian National Guard, Heggelia (control group). The study resulted in an increase in the total consumption of vegetables, fruits, berries and juice (P < 0.001) and of wholegrain bread (P < 0.001). The participants in the intervention group showed a higher increase in the intake of dietary fibre (P < 0.001) and folate (P < 0.001) compared with the control group. The relative contribution of folate intake from fruits, vegetables and wholegrain bread was higher in the intervention group compared with the control group (P < 0.001 for all). The increased intake of folate from wholegrain bread was inversely associated with a reduced concentration of p-tHcy (P = 0.017). In summary, the dietary intervention resulted in an increased intake of vegetables, fruits and wholegrain bread and a subsequent increase in folate intake from these food components. Reduction in the concentration of p-tHcy was significantly related to an increased folate intake due to an increased consumption of wholegrain bread.


A unique cell division machinery in the Archaea.

Abstract: In contrast to the cell division machineries of bacteria, euryarchaea, and eukaryotes, no division components have been identified in the second main archaeal phylum, Crenarchaeota. Here, we demonstrate that a three-gene operon, cdv, in the crenarchaeon Sulfolobus acidocaldarius, forms part of a unique cell division machinery. The operon is induced at the onset of genome segregation and division, and the Cdv proteins then polymerize between segregating nucleoids and persist throughout cell division, forming a successively smaller structure during constriction. The cdv operon is dramatically down-regulated after UV irradiation, indicating division inhibition in response to DNA damage, reminiscent of eukaryotic checkpoint systems. The cdv genes exhibit a complementary phylogenetic range relative to FtsZ-based archaeal division systems such that, in most archaeal lineages, either one or the other system is present. Two of the Cdv proteins, CdvB and CdvC, display homology to components of the eukaryotic ESCRT-III sorting complex involved in budding of luminal vesicles and HIV-1 virion release, suggesting mechanistic similarities and a common evolutionary origin.


A general role for splicing enhancers in exon definition.

Abstract: Exonic splicing enhancers (ESEs) facilitate exon definition by assisting in the recruitment of splicing factors to the adjacent intron. Here we demonstrate that suboptimal 5' and 3' splice sites are activated independently by ESEs when they are located on different exons. However, when they are situated within a single exon, the same weak 5' and 3' splice sites are activated simultaneously by a single ESE. These findings demonstrate that a single ESE promotes the recognition of both exon/intron junctions within the same step during exon definition. Our results suggest that ESEs recruit a multicomponent complex that minimally contains components of the splicing machinery required for 5' and 3' splice site selection.


Imaging the expression of transfected genes in vivo.

Abstract: Imaging the expression of successful gene transduction has been demonstrated in vivo for the first time by using an appropriate combination of "marker gene" and "marker substrate" in an experimental animal model. The herpes simplex virus 1 thymidine kinase (HSV1-tk) gene was selected as an example of a marker gene, and the recombinant STK retrovirus containing HSV1-tk was used to transduce RG2 glioma cells in vitro and in vivo. RG2TK+ cell lines expressing the HSV1-tk gene and three potential marker substrates for the HSV1-TK enzyme were evaluated. Radiolabeled 5-iodo-2'-fluoro-2'deoxy-1-beta-D-arabinofuranosyluracil (FIAU) was shown to be a substantially better marker substrate for the HSV1-TK enzyme than 5-iodo-2'-deoxyuridine or ganciclovir. The magnitude of FIAU accumulation in different RG2TK+ clones corresponded to their sensitivity to ganciclovir and to the level of HSV1-tk mRNA expression. Imaging the expression of HSV1-tk in transduced RG2 tumor cells was demonstrated in animals using quantitative autoradiography; 2-[14C]FIAU accumulation was shown to be high in RG2TK+ brain tumors growing in one hemisphere and very low in nontransduced RG2 tumors in the contralateral hemisphere. Transduction of RG2 tumor cells with the HSV-tk gene in vivo resulted in tumors which accumulated FIAU to high levels and produced clearly defined images. Given the level of FIAU accumulation in the transduced tumors, it is likely that a clinically applicable method for imaging HSV1-tk gene expression can be implemented using existing clinical imaging techniques.


Immune cells contribute to the maintenance of neurogenesis and spatial learning abilities in adulthood

Abstract: Neurogenesis is known to take place in the adult brain. This work identifies T lymphocytes and microglia as being important to the maintenance of hippocampal neurogenesis and spatial learning abilities in adulthood. Hippocampal neurogenesis induced by an enriched environment was associated with the recruitment of T cells and the activation of microglia. In immune-deficient mice, hippocampal neurogenesis was markedly impaired and could not be enhanced by environmental enrichment, but was restored and boosted by T cells recognizing a specific CNS antigen. CNS-specific T cells were also found to be required for spatial learning and memory and for the expression of brain-derived neurotrophic factor in the dentate gyrus, implying that a common immune-associated mechanism underlies different aspects of hippocampal plasticity and cell renewal in the adult brain.


Functional inhibition of osteoblastic cells in an in vivo mouse model of myeloid leukemia.

Abstract: Pancytopenia is a major cause of morbidity in acute myeloid leukemia (AML), yet its cause is unclear. Normal osteoblastic cells have been shown to support hematopoiesis. To define the effects of leukemia on osteoblastic cells, we used an immunocompetent murine model of AML. Leukemic mice had inhibition of osteoblastic cells, with decreased serum levels of the bone formation marker osteocalcin. Osteoprogenitor cells and endosteal-lining osteopontin(+) cells were reduced, and osteocalcin mRNA in CD45(-) marrow cells was diminished. This resulted in severe loss of mineralized bone. Osteoclasts were only transiently increased without significant increases in bone resorption, and their inhibition only partially rescued leukemia-induced bone loss. In vitro data suggested that a leukemia-derived secreted factor inhibited osteoblastic cells. Because the chemokine CCL-3 was recently reported to inhibit osteoblastic function in myeloma, we tested its expression in our model and in AML patients. Consistent with its potential novel role in leukemic-dependent bone loss, CCL-3 mRNA was significantly increased in malignant marrow cells from leukemic mice and from samples from AML patients. Based on these results, we propose that therapeutic mitigation of leukemia-induced uncoupling of osteoblastic and osteoclastic cells may represent a novel approach to promote normal hematopoiesis in patients with myeloid neoplasms.


Cohort profile: the China Health and Retirement Longitudinal Study (CHARLS).

Abstract: The China Health and Retirement Longitudinal Study (CHARLS) is a nationally representative longitudinal survey of persons in China 45 years of age or older and their spouses, including assessments of social, economic, and health circumstances of community-residents. CHARLS examines health and economic adjustments to rapid ageing of the population in China. The national baseline survey for the study was conducted between June 2011 and March 2012 and involved 17 708 respondents. CHARLS respondents are followed every 2 years, using a face-to-face computer-assisted personal interview (CAPI). Physical measurements are made at every 2-year follow-up, and blood sample collection is done once in every two follow-up periods. A pilot survey for CHARLS was conducted in two provinces of China in 2008, on 2685 individuals, who were resurveyed in 2012. To ensure the adoption of best practices and international comparability of results, CHARLS was harmonized with leading international research studies in the Health and Retirement Study (HRS) model. Requests for collaborations should be directed to Dr Yaohui Zhao (yhzhao@nsd.edu.cn). All data in CHARLS are maintained at the National School of Development of Peking University and will be accessible to researchers around the world at the study website. The 2008 pilot data for CHARLS are available at: http://charls.ccer.edu.cn/charls/. National baseline data for the study are expected to be released in January 2013.


Identification of Epstein-Barr virus nuclear antigen 1 protein domains that direct interactions at a distance between DNA-bound proteins.

Abstract: The EBNA1 protein of Epstein-Barr virus (EBV) binds to and activates DNA replication from the EBV latent origin of replication, oriP, via a direct interaction with the two noncontiguous subelements of oriP. The EBNA1 molecules bound to the oriP subelements interact efficiently with each other by a DNA looping mechanism. We have previously mapped a region of EBNA1 (termed the looping region) that is required to mediate the interaction of the EBNA1 molecules bound to the oriP subelements. We now demonstrate that two fragments of this region of EBNA1, which consist largely of an eight amino acid repeat, can mediate homotypic interactions when transferred to another DNA-binding protein. Protein interactions mediated by the EBNA1 looping region appear to be dependent on DNA binding since these interactions were detected between DNA-bound forms of the proteins only.


Organization of the mitotic chromosome.

Abstract: Mitotic chromosomes are among the most recognizable structures in the cell, yet for over a century their internal organization remains largely unsolved. We applied chromosome conformation capture methods, 5C and Hi-C, across the cell cycle and revealed two distinct three-dimensional folding states of the human genome. We show that the highly compartmentalized and cell type-specific organization described previously for nonsynchronous cells is restricted to interphase. In metaphase, we identified a homogenous folding state that is locus-independent, common to all chromosomes, and consistent among cell types, suggesting a general principle of metaphase chromosome organization. Using polymer simulations, we found that metaphase Hi-C data are inconsistent with classic hierarchical models and are instead best described by a linearly organized longitudinally compressed array of consecutive chromatin loops.


Opposing Effects of PKCθ and WASp on Symmetry Breaking and Relocation of the Immunological Synapse

Abstract: The immunological synapse (IS) is a junction between the T cell and antigen-presenting cell and is composed of supramolecular activation clusters (SMACs). No studies have been published on naive T cell IS dynamics. Here, we find that IS formation during antigen recognition comprises cycles of stable IS formation and autonomous naive T cell migration. The migration phase is driven by PKCtheta, which is localized to the F-actin-dependent peripheral (p)SMAC. PKCtheta(-/-) T cells formed hyperstable IS in vitro and in vivo and, like WT cells, displayed fast oscillations in the distal SMAC, but they showed reduced slow oscillations in pSMAC integrity. IS reformation is driven by the Wiscott Aldrich Syndrome protein (WASp). WASp(-/-) T cells displayed normal IS formation but were unable to reform IS after migration unless PKCtheta was inhibited. Thus, opposing effects of PKCtheta and WASp control IS stability through pSMAC symmetry breaking and reformation.


Towards an improved investment approach for an effective response to HIV/AIDS.

Abstract: Substantial changes are needed to achieve a more targeted and strategic approach to investment in the response to the HIV/AIDS epidemic that will yield long-term dividends. Until now, advocacy for resources has been done on the basis of a commodity approach that encouraged scaling up of numerous strategies in parallel, irrespective of their relative effects. We propose a strategic investment framework that is intended to support better management of national and international HIV/AIDS responses than exists with the present system. Our framework incorporates major efficiency gains through community mobilisation, synergies between programme elements, and benefits of the extension of antiretroviral therapy for prevention of HIV transmission. It proposes three categories of investment, consisting of six basic programmatic activities, interventions that create an enabling environment to achieve maximum effectiveness, and programmatic efforts in other health and development sectors related to HIV/AIDS. The yearly cost of achievement of universal access to HIV prevention, treatment, care, and support by 2015 is estimated at no less than US$22 billion. Implementation of the new investment framework would avert 12·2 million new HIV infections and 7·4 million deaths from AIDS between 2011 and 2020 compared with continuation of present approaches, and result in 29·4 million life-years gained. The framework is cost effective at $1060 per life-year gained, and the additional investment proposed would be largely offset from savings in treatment costs alone.


Adverse Events Associated With the Treatment of Multidrug-Resistant Tuberculosis: A Systematic Review and Meta-analysis.

Abstract: Multidrug-resistant tuberculosis (MDR-TB) is a growing public health problem. Due to long duration of therapy and concurrent use of multiple second-line drugs, adverse drug events (ADEs) are regarded as the most important clinical consideration in patients undergoing anti-MDR-TB treatment. To evaluate the frequency and type of treatment-related ADEs owing to MDR-TB therapy. The Cochrane Library, MEDLINE, and EMBASE were searched from inception through October 1, 2012, with additional manual search of International Journal of Tuberculosis and Lung Disease. Studies with available ADEs were selected if MDR-TB patients were treated with regimen including second-line drugs. Pooled estimations of incidence for each specific type of ADEs were calculated with 95% confidence intervals using random-effects model. Of the 5346 patients included, 2602 (57.3%) experienced at least 1 kind of ADE. The 3 most common side effects were gastrointestinal disorders (32.1%), ototoxicity (14.6%), and psychiatric disorders (13.2%). Subgroup analyses based on each characteristic (study population, previous tuberculosis treated, human immunodeficiency virus prevalence, and length of treatment) did not show any significant difference between groups. Additionally, among 1519 patients who developed ADEs with available data of impact on MDR-TB therapy, 70.4% required change of MDR-TB treatment. Adverse events were common among MDR-TB cases, occurring in more than half of the cases, with over two-thirds requiring change of anti-MDR-TB treatment. MDR-TB patients should be monitored closely and managed aggressively for side effects during therapy, especially for ototoxicity and psychiatric disorders.


Presynaptically Localized Cyclic GMP-Dependent Protein Kinase 1 Is a Key Determinant of Spinal Synaptic Potentiation and Pain Hypersensitivity

Abstract: Synaptic long-term potentiation (LTP) at spinal neurons directly communicating pain-specific inputs from the periphery to the brain has been proposed to serve as a trigger for pain hypersensitivity in pathological states. Previous studies have functionally implicated the NMDA receptor-NO pathway and the downstream second messenger, cGMP, in these processes. Because cGMP can broadly influence diverse ion-channels, kinases, and phosphodiesterases, pre- as well as post-synaptically, the precise identity of cGMP targets mediating spinal LTP, their mechanisms of action, and their locus in the spinal circuitry are still unclear. Here, we found that Protein Kinase G1 (PKG-I) localized presynaptically in nociceptor terminals plays an essential role in the expression of spinal LTP. Using the Cre-lox P system, we generated nociceptor-specific knockout mice lacking PKG-I specifically in presynaptic terminals of nociceptors in the spinal cord, but not in post-synaptic neurons or elsewhere (SNS-PKG-I(-/-) mice). Patch clamp recordings showed that activity-induced LTP at identified synapses between nociceptors and spinal neurons projecting to the periaqueductal grey (PAG) was completely abolished in SNS-PKG-I(-/-) mice, although basal synaptic transmission was not affected. Analyses of synaptic failure rates and paired-pulse ratios indicated a role for presynaptic PKG-I in regulating the probability of neurotransmitter release. Inositol 1,4,5-triphosphate receptor 1 and myosin light chain kinase were recruited as key phosphorylation targets of presynaptic PKG-I in nociceptive neurons. Finally, behavioural analyses in vivo showed marked defects in SNS-PKG-I(-/-) mice in several models of activity-induced nociceptive hypersensitivity, and pharmacological studies identified a clear contribution of PKG-I expressed in spinal terminals of nociceptors. Our results thus indicate that presynaptic mechanisms involving an increase in release probability from nociceptors are operational in the expression of synaptic LTP on spinal-PAG projection neurons and that PKG-I localized in presynaptic nociceptor terminals plays an essential role in this process to regulate pain sensitivity.


Development of leukemia in donor cells after allogeneic stem cell transplantation--a survey of the European Group for Blood and Marrow Transplantation (EBMT).

Abstract: Leukemia in donor cells (donor cell leukemia; DCL) has been reported as a rare but severe complication of allogeneic stem cell transplantation (SCT). However, the incidence, potential pathogenetic factors, therapeutic options and outcome of patients suffering from DCL and the leukemia risk of their donors are not well defined. A questionnaire survey was carried out within European Blood and Marrow Transplantation Group (EBMT) centers. Ninety-one EBMT centers participated in this survey, covering 10489 allogeneic SCT between 12/1982 and 09/2003. Fourteen cases of DCL, most with a myeloid phenotype (7 cases of acute myeloid leukemia, 3 each of acute lymphocytic leukemia and 1 case of chronic myeloid leukemia) were identified. Demonstration of donor cell origin included molecular analysis of chimerism in most cases. DCL type and cytogenetic alterations were independent from the original disease. The median time between transplantation and diagnosis of DCL was 17 months (4-164). No type of conditioning, donor, graft manipulation, graft-versus-host disease prophylaxis or subsequent complications were identified as risk factors for DCL. Chemotherapy induced remissions in DCL and 2 of 5 patients remain alive in remission after a second transplant. None of the stem cell donors developed hematologic malignancies (median follow-up period of 9 years; range 6-30 years). DCL is an extremely rare complication of allogeneic SCT in which treatment attempts with chemotherapy and a second SCT are justified. Donors are not at an increased risk of developing hematologic malignancies.


Effect of a C/EBP gene replacement on mitochondrial biogenesis in fat cells.

Abstract: CCAAT/enhancer-binding proteins, C/EBPalpha and C/EBPbeta, are required for fat cell differentiation and maturation. Previous studies showed that replacement of C/EBPalpha with C/EBPbeta, generating the beta/beta alleles in the mouse genome, prevents lipid accumulation in white adipose tissue (WAT). In this study, beta/beta mice lived longer and had higher energy expenditure than their control littermates due to increased WAT energy oxidation. The WAT of beta/beta mice was enriched with metabolically active, thermogenic mitochondria known for energy burning. The beta/beta allele exerted its effect through the elevated expression of the G protein alpha stimulatory subunit (Galphas) in WAT. Galphas, when overexpressed in fat-laden 3T3-L1 cells, stimulated mitochondrial biogenesis similar to that seen in the WAT of beta/beta mice, and effectively diminished the stored lipid pool.


Body-mass index and mortality in Korean men and women.

Abstract:
BACKGROUND Obesity is associated with diverse health risks, but the role of body weight as a risk factor for death remains controversial.
 METHODS We examined the association between body weight and the risk of death in a 12-year prospective cohort study of 1,213,829 Koreans between the ages of 30 and 95 years. We examined 82,372 deaths from any cause and 48,731 deaths from specific diseases (including 29,123 from cancer, 16,426 from atherosclerotic cardiovascular disease, and 3362 from respiratory disease) in relation to the body-mass index (BMI) (the weight in kilograms divided by the square of the height in meters).
 RESULTS In both sexes, the average baseline BMI was 23.2, and the rate of death from any cause had a J-shaped association with the BMI, regardless of cigarette-smoking history. The risk of death from any cause was lowest among patients with a BMI of 23.0 to 24.9. In all groups, the risk of death from respiratory causes was higher among subjects with a lower BMI, and the risk of death from atherosclerotic cardiovascular disease or cancer was higher among subjects with a higher BMI. The relative risk of death associated with BMI declined with increasing age.
 CONCLUSIONS Underweight, overweight, and obese men and women had higher rates of death than men and women of normal weight. The association of BMI with death varied according to the cause of death and was modified by age, sex, and smoking history.


Maintaining the norm: T-cell homeostasis

Abstract: The persistence of naive and memory T cells has long been of interest to immunologists, but the factors that influence the survival and homeostasis of these subsets have remained obscure. In recent years, it has become evident that the homeostasis of both naive and memory T-cell pools is highly dynamic and tightly regulated by internal stimuli, including cytokines and self-peptide–MHC ligands for the T-cell receptor. These homeostatic mechanisms might have a vital influence on the capacity of the T-cell pool to respond to both foreign and self-antigens.