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43647194
The availability of valid migraine-specific questionnaires is important when large numbers of migraine patients have to be analysed. The Finnish Migraine-Specific Questionnaire has been validated in two stages. In the first, a clinical diagnosis of migraine was reached, using International Headache Society criteria, in 100 consecutive patients. Migraine was then diagnosed independently on the basis of responses to the Finnish Migraine-Specific Questionnaire. In the second stage, responses to 100 questionnaires returned consecutively in a family study in progress were analysed, and respondents were contacted by telephone for interview and diagnosis of migraine. Contact proved impossible in six cases. The sensitivity of the questionnaire for migraine was 0.99 (167 out of 168; validation stages 1 and 2 combined) and specificity was 0.96 (25 out of 26 cases; validation stage 2). It also proved possible to differentiate between migraine with and without aura on the basis of responses to the Finnish Migraine-Specific Questionnaire: chance-corrected agreement (Cohen's kappa) was 0.804 in relation to diagnoses reached on the basis of responses to the Finnish Migraine-Specific Questionnaire and clinically was 0.858 in relation to diagnoses reached on the basis of responses to the Finnish Migraine-Specific Questionnaire combined with the results of the telephone interviews. A value for Cohen's kappa > 0.75 indicates good agreement. Therefore, use of the Finnish Migraine-Specific Questionnaire in research into migraine genetics is justified.
Validation of a migraine-specific questionnaire for use in family studies.
43661837
The canonical Wnt/beta-catenin signaling has remarkably diverse roles in embryonic development, stem cell self-renewal and cancer progression. Here, we show that stabilized expression of beta-catenin perturbed human embryonic stem (hES)-cell self-renewal, such that up to 80% of the hES cells developed into the primitive streak (PS)/mesoderm progenitors, reminiscent of early mammalian embryogenesis. The formation of the PS/mesoderm progenitors essentially depended on the cooperative action of beta-catenin together with Activin/Nodal and BMP signaling pathways. Intriguingly, blockade of BMP signaling completely abolished mesoderm generation, and induced a cell fate change towards the anterior PS progenitors. The PI3-kinase/Akt, but not MAPK, signaling pathway had a crucial role in the anterior PS specification, at least in part, by enhancing beta-catenin stability. In addition, Activin/Nodal and Wnt/beta-catenin signaling synergistically induced the generation and specification of the anterior PS/endoderm. Taken together, our findings clearly demonstrate that the orchestrated balance of Activin/Nodal and BMP signaling defines the cell fate of the nascent PS induced by canonical Wnt/beta-catenin signaling in hES cells.
Defining early lineage specification of human embryonic stem cells by the orchestrated balance of canonical Wnt/beta-catenin, Activin/Nodal and BMP signaling.
43700577
Consistent with previous reports, sphingosine at a high concentration (5 microM) was cardiotoxic as evidenced by increased infarct size in response to ischemia/reperfusion in an ex vivo rat heart. Sphingosine 1-phosphate (S1P) at 5 microM was cardioprotective. However, at a physiologic concentration (0.4 microM) sphingosine as well as S1P was effective in protecting the heart from ischemia/reperfusion injury both when perfused prior to 40 min of ischemia (preconditioning) or when added to reperfusion media following ischemia (postconditioning). Protection by sphingosine and S1P was evidenced with both pre- and post-conditioning by a >75% recovery of left ventricular developed pressure during reperfusion and a decrease in infarct size from 45% of the risk area to less than 8%. When VPC23019, an S1P(1and3)G-protein coupled receptor antagonist, was added to the preconditioning or postconditioning medium along with S1P, it completely blocked S1P-induced protection. However, VPC 23019 did not affect the ability of 0.4 microM sphingosine to either precondition or postcondition hearts. Studies of preconditioning revealed that inhibition of protein kinase C with GF109203X blocked preconditioning by S1P. However, GF109203X did not affect preconditioning by 0.4 microM sphingosine. Likewise, cotreatment with the PI3 kinase inhibitor wortmanin blocked preconditioning by S1P but not by sphingosine. By contrast, inhibition of protein kinase G with KT5823 had no effect on S1P preconditioning but completely eliminated preconditioning by sphingosine. Also, the protein kinase A inhibitory peptide 14-22 amide blocked preconditioning by sphingosine but not S1P. These data reveal for the first time that sphingosine is not toxic at physiologic concentrations but rather is a potent cardioprotectant that utilizes a completely different mechanism than S1P; one that is independent of G-protein coupled receptors and utilizes cyclic nucleotide-dependent pathways.
Sphingosine can pre- and post-condition heart and utilizes a different mechanism from sphingosine 1-phosphate.
43711341
Transcriptional coactivators showing physical and functional interactions with PPARgamma include the protein acetyl transferase p300, the TRAP/Mediator complex that interacts with the general transcription machinery, and the highly regulated PGC-1alpha. We show that PGC-1alpha directly interacts with TRAP/Mediator, through the PPARgamma-interacting subunit TRAP220, and stimulates TRAP/Mediator-dependent function on DNA templates. Further, while ineffective by itself, PGC-1alpha stimulates p300-dependent histone acetylation and transcription on chromatin templates in response to PPARgamma. These functions are mediated by largely independent PPARgamma, p300, and TRAP220 interaction domains in PGC-1alpha, whereas p300 and TRAP220 show ligand-dependent interactions with a common region of PPARgamma. Apart from showing PGC-1alpha functions both in chromatin remodeling and in preinitiation complex formation or function (transcription), these results suggest a key role for PGC-1alpha, through concerted but dynamic interactions, in coordinating these steps.
Coordination of p300-mediated chromatin remodeling and TRAP/mediator function through coactivator PGC-1alpha.
43752562
Subcellular membranes of Saccharomyces cerevisiae, including mitochondria, microsomes, plasma membranes, secretory vesicles, vacuoles, nuclear membranes, peroxisomes, and lipid particles, were isolated by improved procedures and analyzed for their lipid composition and their capacity to synthesize phospholipids and to catalyze sterol delta 24-methylation. The microsomal fraction is heterogeneous in terms of density and classical microsomal marker proteins and also with respect to the distribution of phospholipid-synthesizing enzymes. The specific activity of phosphatidylserine synthase was highest in a microsomal subfraction which was distinct from heavier microsomes harboring phosphatidylinositol synthase and the phospholipid N-methyltransferases. The exclusive location of phosphatidylserine decarboxylase in mitochondria was confirmed. CDO-diacylglycerol synthase activity was found both in mitochondria and in microsomal membranes. Highest specific activities of glycerol-3-phosphate acyltransferase and sterol delta 24-methyltransferase were observed in the lipid particle fraction. Nuclear and plasma membranes, vacuoles, and peroxisomes contain only marginal activities of the lipid-synthesizing enzymes analyzed. The plasma membrane and secretory vesicles are enriched in ergosterol and in phosphatidylserine. Lipid particles are characterized by their high content of ergosteryl esters. The rigidity of the plasma membrane and of secretory vesicles, determined by measuring fluorescence anisotropy by using trimethylammonium diphenylhexatriene as a probe, can be attributed to the high content of ergosterol.
Phospholipid synthesis and lipid composition of subcellular membranes in the unicellular eukaryote Saccharomyces cerevisiae.
43855756
The future organisation of prison health care 1 recommends that the NHS and the Prison Service work together to plan and provide health care services for prisoners. Whereas previously the Prison Service had this responsibility alone. The NHS will therefore have to take stock of the current level at which prison health care is demanded and provided. A key part of the information base for joint planning therefore includes data on current service utilisation. This paper compares primary care and inpatient health service utilisation data for UK prisoners with health services utilisation data for equivalent community populations. In the community, primary care is provided principally by general practitioners and professions allied to medicine (mostly nurses). Residents in the community have access to the full range of NHS outpatient and inpatient facilities. Within prisons, primary care is provided by medical officers (some of whom are general practitioners), nursing grades and health care officers (who have received some training in health care). Some prisons have their own inpatient facilities (health care centre beds). These provide a low level of inpatient care and do not have a direct equivalent in the community. Prisoners also have access to NHS outpatient and inpatient facilities and to visiting specialists. The prison population has a high turnover and varies from day to day. Because of this, the prison population is expressed as an average daily population during a one year period. …
Use of health services by prison inmates: comparisons with the community.
43880096
Activation of p53 can occur in response to a number of cellular stresses, including DNA damage, hypoxia and nucleotide deprivation. Several forms of DNA damage have been shown to activate p53, including those generated by ionising radiation (IR), radio-mimetic drugs, ultraviolet light (UV) and chemicals such as methyl methane sulfonate (MMS). Under normal conditions, p53 levels are maintained at a low state by virtue of the extremely short-half life of the polypeptide. In addition to this, p53 normally exists in an largely inactive state that is relatively inefficient at binding to DNA and activating transcription. Activation of p53 in response to DNA damage is associated with a rapid increase in its levels and with an increased ability of p53 to bind DNA and mediate transcriptional activation. This then leads to the activation of a number of genes whose products trigger cell-cycle arrest, apoptosis, or DNA repair. Recent work has suggested that this regulation is brought about largely through DNA damage triggering a series of phosphorylation, de-phosphorylation and acetylation events on the p53 polypeptide. Here, we discuss the nature of these modifications, the enzymes that bring them about, and how changes in p53 modification lead to p53 activation.
Regulation of p53 in response to DNA damage
43890638
We investigated the role of hydrogen sulphide (H(2)S) in intracellular pH (pH(i)) regulation in vascular smooth muscle cells and its contribution on vasodilation. NaHS, a H(2)S donor, decreased pH(i) in a concentration-dependent manner ranging from 10 microM to 1mM. Neither inhibition of the Na(+)/H(+) exchanger with 5-(N-ethyl-N-isopropyl) amiloride, (EIPA, 10 microM), nor plasmalemmal Ca(2+)-ATPase with CdCl(2) (20nM) alters the effect of NaHS on pH(i). Blockade of the Cl(-)/HCO3- exchanger with 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) significantly attenuated the pH(i) lowering effect of NaHS. Moreover, NaHS significantly increased the activity of Cl(-)/HCO3- exchanger when measured with NH(4)Cl prepulse method. DIDS attenuated the vasorelaxation induced by NaHS whereas EIPA and CdCl(2) did not cause any change. In conclusion, H(2)S induced intracellular acidification via activation of Cl(-)/HCO3- exchanger, which is, at least partially, responsible for H(2)S-mediated vasorelaxation.
Hydrogen sulphide regulates intracellular pH in vascular smooth muscle cells.
43990286
Tissue engineering frequently involves cells and scaffolds to replace damaged or diseased tissue. It originated, in part, as a means of effecting the delivery of biomolecules such as insulin or neurotrophic factors, given that cells are constitutive producers of such therapeutic agents. Thus cell delivery is intrinsic to tissue engineering. Controlled release of biomolecules is also an important tool for enabling cell delivery since the biomolecules can enable cell engraftment, modulate inflammatory response or otherwise benefit the behavior of the delivered cells. We describe advances in cell and biomolecule delivery for tissue regeneration, with emphasis on the central nervous system (CNS). In the first section, the focus is on encapsulated cell therapy. In the second section, the focus is on biomolecule delivery in polymeric nano/microspheres and hydrogels for the nerve regeneration and endogenous cell stimulation. In the third section, the focus is on combination strategies of neural stem/progenitor cell or mesenchymal stem cell and biomolecule delivery for tissue regeneration and repair. In each section, the challenges and potential solutions associated with delivery to the CNS are highlighted.
Cell and biomolecule delivery for tissue repair and regeneration in the central nervous system.
44030361
Accumulated evidence suggests that an altered ambulatory blood pressure (BP) profile, particularly elevated nighttime BP, reflects target organ injury and is a better predictor of further cardiorenal risk than the clinic BP or daytime BP in hypertensive patients complicated by chronic kidney disease (CKD). In this study, we examined the beneficial effects of olmesartan, an angiotensin II type 1 receptor blocker (ARB), on ambulatory BP profiles and renal function in hypertensive CKD patients. Forty-six patients were randomly assigned to the olmesartan add-on group (n=23) or the non-ARB group (n=23). At baseline and after the 16-week treatment period, ambulatory BP monitoring was performed and renal function parameter measurements were collected. Although the baseline clinic BP levels and the after-treatment/baseline (A/B) ratios of clinic BP levels were similar in the olmesartan add-on and non-ARB groups, the A/B ratios of ambulatory 24-h and nighttime BP levels in the olmesartan add-on group were significantly lower. Furthermore, the A/B ratios of urinary protein, albumin and type IV collagen excretion in the olmesartan add-on group were significantly lower than those in the non-ARB group (urinary protein excretion, 0.72±0.41 vs. 1.45±1.48, P=0.030; urinary albumin excretion, 0.73±0.37 vs. 1.50±1.37, P=0.005; urinary type IV collagen excretion, 0.87±0.42 vs. 1.48±0.87, P=0.014) despite comparable A/B ratios for the estimated glomerular filtration rate in the two groups. These results indicate that in hypertensive patients with CKD, olmesartan add-on therapy improves the ambulatory BP profile via a preferential reduction in nighttime BP with concomitant renal injury inhibition.
The angiotensin II type 1 receptor blocker olmesartan preferentially improves nocturnal hypertension and proteinuria in chronic kidney disease
44048701
IMPORTANCE The need for surgery for the majority of patients with displaced proximal humeral fractures is unclear, but its use is increasing. OBJECTIVE To evaluate the clinical effectiveness of surgical vs nonsurgical treatment for adults with displaced fractures of the proximal humerus involving the surgical neck. DESIGN, SETTING, AND PARTICIPANTS A pragmatic, multicenter, parallel-group, randomized clinical trial, the Proximal Fracture of the Humerus Evaluation by Randomization (PROFHER) trial, recruited 250 patients aged 16 years or older (mean age, 66 years [range, 24-92 years]; 192 [77%] were female; and 249 [99.6%] were white) who presented at the orthopedic departments of 32 acute UK National Health Service hospitals between September 2008 and April 2011 within 3 weeks after sustaining a displaced fracture of the proximal humerus involving the surgical neck. Patients were followed up for 2 years (up to April 2013) and 215 had complete follow-up data. The data for 231 patients (114 in surgical group and 117 in nonsurgical group) were included in the primary analysis. INTERVENTIONS Fracture fixation or humeral head replacement were performed by surgeons experienced in these techniques. Nonsurgical treatment was sling immobilization. Standardized outpatient and community-based rehabilitation was provided to both groups. MAIN OUTCOMES AND MEASURES Primary outcome was the Oxford Shoulder Score (range, 0-48; higher scores indicate better outcomes) assessed during a 2-year period, with assessment and data collection at 6, 12, and 24 months. Sample size was based on a minimal clinically important difference of 5 points for the Oxford Shoulder Score. Secondary outcomes were the Short-Form 12 (SF-12), complications, subsequent therapy, and mortality. RESULTS There was no significant mean treatment group difference in the Oxford Shoulder Score averaged over 2 years (39.07 points for the surgical group vs 38.32 points for the nonsurgical group; difference of 0.75 points [95% CI, -1.33 to 2.84 points]; P = .48) or at individual time points. There were also no significant between-group differences over 2 years in the mean SF-12 physical component score (surgical group: 1.77 points higher [95% CI, -0.84 to 4.39 points]; P = .18); the mean SF-12 mental component score (surgical group: 1.28 points lower [95% CI, -3.80 to 1.23 points]; P = .32); complications related to surgery or shoulder fracture (30 patients in surgical group vs 23 patients in nonsurgical group; P = .28), requiring secondary surgery to the shoulder (11 patients in both groups), and increased or new shoulder-related therapy (7 patients vs 4 patients, respectively; P = .58); and mortality (9 patients vs 5 patients; P = .27). Ten medical complications (2 cardiovascular events, 2 respiratory events, 2 gastrointestinal events, and 4 others) occurred in the surgical group during the postoperative hospital stay. CONCLUSIONS AND RELEVANCE Among patients with displaced proximal humeral fractures involving the surgical neck, there was no significant difference between surgical treatment compared with nonsurgical treatment in patient-reported clinical outcomes over 2 years following fracture occurrence. These results do not support the trend of increased surgery for patients with displaced fractures of the proximal humerus. TRIAL REGISTRATION isrctn.com Identifier: ISRCTN50850043.
Surgical vs nonsurgical treatment of adults with displaced fractures of the proximal humerus: the PROFHER randomized clinical trial.
44172171
The RNA-guided DNA endonuclease Cas9 is a powerful tool for genome editing. Little is known about the kinetics and fidelity of the double-strand break (DSB) repair process that follows a Cas9 cutting event in living cells. Here, we developed a strategy to measure the kinetics of DSB repair for single loci in human cells. Quantitative modeling of repaired DNA in time series after Cas9 activation reveals variable and often slow repair rates, with half-life times up to ∼10 hr. Furthermore, repair of the DSBs tends to be error prone. Both classical and microhomology-mediated end joining pathways contribute to the erroneous repair. Estimation of their individual rate constants indicates that the balance between these two pathways changes over time and can be altered by additional ionizing radiation. Our approach provides quantitative insights into DSB repair kinetics and fidelity in single loci and indicates that Cas9-induced DSBs are repaired in an unusual manner.
Kinetics and Fidelity of the Repair of Cas9-Induced Double-Strand DNA Breaks
44264297
I present methods for assessing the relative effectiveness of two treatments when they have not been compared directly in a randomized trial but have each been compared to other treatments. These network meta-analysis techniques allow estimation of both heterogeneity in the effect of any given treatment and inconsistency ('incoherence') in the evidence from different pairs of treatments. A simple estimation procedure using linear mixed models is given and used in a meta-analysis of treatments for acute myocardial infarction.
Network meta-analysis for indirect treatment comparisons.
44265107
ContextChronic hepatitis C is the leading cause for liver transplantation in the United States. Intravenous drug use, the major risk factor, accounts for approximately 60% of hepatitis C virus transmission. Information from the United Network of Organ Sharing (UNOS) does not address substance use among liver transplantation patients. ObjectiveTo identify addiction-related criteria for admission to the UNOS liver transplantation waiting list and posttransplantation problems experienced by patients who are prescribed maintenance methadone. Design, Setting, and ParticipantsMail survey of all 97 adult US liver transplantation programs (belonging to UNOS) in March 2000 with telephone follow-up conducted in May and June 2000.Main Outcome MeasuresPrograms' acceptance and management of patients with past or present substance use disorder. ResultsOf the 97 programs surveyed, 87 (90%) responded. All accept applicants with a history of alcoholism or other addictions, including heroin dependence. Eighty-eight percent of the responding programs require at least 6 months of abstinence from alcohol; 83% from illicit drugs. Ninety-four percent have addiction treatment requirements. Consultations from substance abuse specialists are obtained by 86%. Patients receiving methadone maintenance are accepted by 56% of the responding programs. Approximately 180 patients receiving methadone maintenance are reported to have undergone liver transplantation. ConclusionsMost liver transplantation programs have established policies for patients with substance use disorders. Opiate-dependent patients receiving opiate replacement therapy seem underrepresented in transplantation programs. Little anecdotal evidence for negative impact of opiate replacement therapy on liver transplantation outcome was found. Policies requiring discontinuation of methadone in 32% of all programs contradict the evidence base for efficacy of long-term replacement therapies and potentially result in relapse of previously stable patients.
Liver transplantation and opioid dependence.
44366096
Double-stranded RNA (dsRNA) produced during viral replication is believed to be the critical trigger for activation of antiviral immunity mediated by the RNA helicase enzymes retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5). We showed that influenza A virus infection does not generate dsRNA and that RIG-I is activated by viral genomic single-stranded RNA (ssRNA) bearing 5'-phosphates. This is blocked by the influenza protein nonstructured protein 1 (NS1), which is found in a complex with RIG-I in infected cells. These results identify RIG-I as a ssRNA sensor and potential target of viral immune evasion and suggest that its ability to sense 5'-phosphorylated RNA evolved in the innate immune system as a means of discriminating between self and nonself.
RIG-I-mediated antiviral responses to single-stranded RNA bearing 5'-phosphates.
44384384
AIMS While randomized clinical trials have compared clopidogrel with higher potency adenosine diphosphate (ADP) receptor inhibitors among patients with acute myocardial infarction, little is known about the frequency, effectiveness and safety of switching between ADP receptor inhibitors in routine clinical practice. METHODS AND RESULTS We studied 11,999 myocardial infarction patients treated with percutaneous coronary intervention at 230 hospitals from April 2010 to October 2012 in the TRANSLATE-ACS study. Multivariable Cox regression was used to compare six-month post-discharge risks of major adverse cardiovascular events (MACE: death, myocardial infarction, stroke, or unplanned revascularization) and Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO)-defined bleeding between in-hospital ADP receptor inhibitor switching versus continuation of the initially selected therapy. Among 8715 patients treated initially with clopidogrel, 994 (11.4%) were switched to prasugrel or ticagrelor; switching occurred primarily after percutaneous coronary intervention (60.9%) and at the time of hospital discharge (26.7%). Among 3284 patients treated initially with prasugrel or ticagrelor, 448 (13.6%) were switched to clopidogrel; 48.2% of switches occurred after percutaneous coronary intervention and 48.0% at hospital discharge. Switching to prasugrel or ticagrelor was not associated with increased bleeding when compared with continuation on clopidogrel (2.7% vs. 3.3%, adjusted hazard ratio 0.96, 95% confidence interval 0.64-1.42, p=0.82). Switching from prasugrel or ticagrelor to clopidogrel was not associated with increased MACE (8.9% vs. 7.7%, adjusted hazard ratio 1.06, 95% confidence interval 0.75-1.49, p=0.76) when compared with continuation on the higher potency agent. CONCLUSIONS In-hospital ADP receptor inhibitor switching occurs in more than one in 10 myocardial infarction patients in contemporary practice. In this observational study, ADP receptor inhibitor switching does not appear to be significantly associated with increased hazard of MACE or bleeding.
In-hospital switching between adenosine diphosphate receptor inhibitors in patients with acute myocardial infarction treated with percutaneous coronary intervention: Insights into contemporary practice from the TRANSLATE-ACS study.
44387884
The abnormal metabolic state that accompanies diabetes renders arteries susceptible to atherosclerosis, being capable of altering the functional properties of multiple cell types, including endothelium and platelets. In particular, an altered platelet metabolism and changes in intraplatelet signaling pathways may contribute to the pathogenesis of atherothrombotic complications of diabetes. A variety of mechanisms may be responsible for enhanced platelet aggregation. Among them, hyperglycemia may represent a causal factor for in vivo platelet activation, and may be responsible for nonenzymatic glycation of platelet glycoproteins, causing changes in their structure and conformation, as well as alterations of membrane lipid dynamics. Furthermore, hyperglycemia-induced oxidative stress is responsible for enhanced peroxidation of arachidonic acid to form biologically active isoprostanes, which represents an important biochemical link between impaired glycemic control and persistent platelet activation. Finally, increased oxidative stress is responsible for activation of transcription factors and expression of redox-sensitive genes leading to a phenotypic switch of endothelium toward an adhesive, pro-thrombotic condition, initial platelet activation, adhesion and subsequent platelet aggregate formation. All this evidence is strengthened by the results of clinical trials documenting the beneficial effects of metabolic control on platelet function, and by the finding that aspirin treatment may even be more beneficial in diabetic than in high-risk non-diabetic patients. Attention to appropriate medical management of diabetic patients will have great impact on long-term outcome in this high-risk population.
Platelet activation in type 2 diabetes mellitus.
44408494
Multiple lines of evidence, from molecular and cellular to epidemiological, have implicated nicotinic transmission in the pathology of Alzheimer's disease (AD) and Parkinson's disease (PD). This review article presents evidence for nicotinic acetylcholine receptor (nAChR)-mediated protection and the signal transduction involved in this mechanism. The data is based mainly on our studies using rat-cultured primary neurons. Nicotine-induced protection was blocked by an alpha7 nAChR antagonist, a phosphatidylinositol 3-kinase (PI3K) inhibitor, and an Src inhibitor. Levels of phosphorylated Akt, an effector of PI3K, Bcl-2 and Bcl-x were increased by nicotine administration. From these experimental data, our hypothesis for the mechanism of nAChR-mediated survival signal transduction is that the alpha7 nAChR stimulates the Src family, which activates PI3K to phosphorylate Akt, which subsequently transmits the signal to up-regulate Bcl-2 and Bcl-x. Up-regulation of Bcl-2 and Bcl-x could prevent cells from neuronal death induced by beta-amyloid (Abeta), glutamate and rotenone. These findings suggest that protective therapy with nAChR stimulation could delay the progress of neurodegenerative diseases such as AD and PD.
Nicotinic receptor-mediated neuroprotection in neurodegenerative disease models.
44409062
In recent years, a new paradigm for genome annotation has emerged, termed "proteogenomics," that leverages peptide MS to annotate a genome. This is achieved by mapping peptides to a six-frame translation of a genome, including available splice databases, which may suggest refinements to gene models. Using this approach, it is possible to refine gene regions such as exon boundaries, novel genes, gene boundaries, frame shifts, reverse strands, translated UTRs, and novel splice junctions. One of the challenges of proteogenomics is how best to (1) tackle assigning confidence to any resulting annotation and (2) apply these gene model refinements, either through manual annotation or through an automated process via training gene prediction tools. This is not a straightforward process, as many gene prediction tools have their defined suitability for niche genomes (either eukaryotic or prokaryotic) trained on and refined with model organisms such as Arabidopsis thaliana and Escherichia coli, and varying degrees of features that can leverage the use of external evidence. In this study, we outline a suitable approach toward preprocessing mass spectra and optimizing the MS/MS search for a given dataset. We also discuss future challenges, which continue to pose a problem in the field of proteogenomics, and better strategies to successfully tackle them with, using existing tools. We use Bradyrhizobium diazoefficiens (Nitrogen-fixing bacteria), with a 9.1 Mb genome as a case study, utilizing the latest in second-generation proteogenomics tools with multiple gene models for cross-validation of proteogenomics annotations.
High-throughput parallel proteogenomics: a bacterial case study.
44420873
The predominant form of the cross-linking enzyme, transglutaminase, in cultured normal human epidermal keratinocytes, is found in cell particulate material and can be solubilized by nonionic detergent. It elutes as a single peak upon either anion-exchange or gel-filtration chromatography. Monoclonal antibodies raised to the particulate enzyme cross-react with one of two transglutaminases in the cell cytosol. The second cytosolic transglutaminase, which has distinct kinetic and physical properties from the first, does not cross-react and is not essential for formation of the keratinocyte cross-linked envelope in vitro. The anti-transglutaminase antibodies stain the more differentiated layers of epidermis in a pattern similar to that given by anti-involucrin antiserum. These observations support the hypothesis that the transglutaminase so identified is involved in cross-linked envelope formation in vivo.
Keratinocyte-specific transglutaminase of cultured human epidermal cells: relation to cross-linked envelope formation and terminal differentiation.
44500794
The aim of this study was to compare the effects of the genetic and pharmacological disruption of CB1 cannabinoid receptors on the elevated plus-maze test of anxiety. In the first experiment, the behaviour of CB1-knockout mice and wild-type mice was compared. In the second experiment, the cannabinoid antagonist SR141716A (0, 1, and 3 mg/kg) was administered to both CB1-knockout and wild type mice. Untreated CB1-knockout mice showed a reduced exploration of the open arms of the plus-maze apparatus, thus appearing more anxious than the wild-type animals, however no changes in locomotion were noticed. The vehicle-injected CB1-knockout mice from the second experiment also showed increased anxiety as compared with wild types. Surprisingly, the cannabinoid antagonist SR141716A reduced anxiety in both wild type and CB1 knockout mice. Locomotor behaviour was only marginally affected. Recent evidence suggests the existence of a novel cannabinoid receptor in the brain. It has also been shown that SR141716A binds to both the CB1 and the putative novel receptor. The data presented here supports these findings, as the cannabinoid receptor antagonist affected anxiety in both wild type and CB1-knockout mice. Tentatively, it may be suggested that the discrepancy between the effects of the genetic and pharmacological blockade of the CB1 receptor suggests that the novel receptor plays a role in anxiety.
The effects of genetic and pharmacological blockade of the CB1 cannabinoid receptor on anxiety.
44562058
Despite complete or near-complete suppression of human immunodeficiency virus (HIV) replication with combination antiretroviral therapy, both HIV and chronic inflammation/immune dysfunction persist indefinitely. Untangling the association between the virus and the host immune environment during therapy might lead to novel interventions aimed at either curing the infection or preventing the development of inflammation-associated end-organ disease. Chronic inflammation and immune dysfunction might lead to HIV persistence by causing virus production, generating new target cells, enabling infecting of activated and resting target cells, altering the migration patterns of susceptible target cells, increasing the proliferation of infected cells, and preventing normal HIV-specific clearance mechanisms from function. Chronic HIV production or replication might contribute to persistent inflammation and immune dysfunction. The rapidly evolving data on these issues strongly suggest that a vicious cycle might exist in which HIV persistence causes inflammation that in turn contributes to HIV persistence.
Immune activation and HIV persistence: implications for curative approaches to HIV infection.
44562221
Endogenous glucocorticoids (GC) play an important role in the termination of the inflammatory response following infection and tissue injury. However, recent findings indicate that stress can impair the anti-inflammatory capacities of these hormones. Lipopolysaccharide (LPS)-stimulated splenocytes of mice that were repeatedly subjected to social disruption (SDR) stress were less sensitive to the immunosuppressive effects of corticosterone (CORT) as demonstrated by an increased production of pro-inflammatory cytokines and enhanced cell survival. Myeloid cells expressing the marker CD11b were shown to play a key role in this process. Here we investigated the role of the bone marrow as a potential source of the GC-insensitive cells. The study revealed that LPS-stimulated bone marrow cells, in the absence of experimental stress, were virtually GC-resistant and retained high levels of cell viability after treatment with CORT. Recurrent exposure to the acute stressor over a period of 2, 4 or 6 days led to an increase in the GC sensitivity of the bone marrow cells. This increase in GC sensitivity was associated with enhanced mRNA expression of granulocyte-macrophage colony-stimulating factor (GM-CSF), an increase in the number of myeloid progenitors, and a decrease in the proportion of mature CD11b+ cells. The changes in the cellular composition of the bone marrow were accompanied by an increase in splenic CD11b+ cell numbers. Simultaneous assessment of the GC sensitivity in bone marrow and spleen revealed a significant negative correlation between both tissues suggesting that social stress causes the redistribution of GC-insensitive myeloid cells from the bone marrow to the spleen.
Tissue-specific alterations in the glucocorticoid sensitivity of immune cells following repeated social defeat in mice
44562904
BACKGROUND Many patients with lung cancer report delays in diagnosing their disease. This may contribute to advanced stage at diagnosis and poor long term survival. This study explores the delays experienced by patients referred to a regional cancer centre with lung cancer. METHODS A prospective cohort of patients referred with newly diagnosed lung cancer were surveyed over a 3 month period to assess delays in diagnosis. Patients were asked when they first experienced symptoms, saw their doctor, what tests were done, when they saw a specialist and when they started treatment. Descriptive statistics were used to summarize the different time intervals. RESULTS 56 of 73 patients consented (RR 77%). However only 52 patients (30M, 22F) were interviewed as 2 died before being interviewed and two could not be contacted. The mean age was 68yrs. Stage distribution was as follows (IB/IIA 10%, stage IIIA 20%, IIIB/IV 70%). Patients waited a median of 21 days (iqr 7-51d) before seeing a doctor and a further 22d (iqr 0-38d) to complete any investigations. The median time from presentation to specialist referral was 27d (iqr 12-49d) and a further 23.5d (iqr 10-56d) to complete investigations. The median wait to start treatment once patients were seen at the cancer centre was 10d (iqr 2-28d). The overall time from development of first symptoms to starting treatment was 138d (iqr 79-175d). CONCLUSIONS Lung cancer patients experience substantial delays from development of symptoms to first initiating treatment. There is a need to promote awareness of lung cancer symptoms and develop and evaluate rapid assessment clinics for patients with suspected lung cancers.
Delays in the diagnosis of lung cancer.
44572913
On the basis of previous epidemiological, clinical and experimental studies, it was demonstrated that adequate calcium intake during growth may influence peak bone mass/density, and may be instrumental in preventing subsequent postmenopausal and senile osteoporosis. Calcium intake during adolescence appears to affect skeletal calcium retention directly, and a calcium intake of up to 1600 mg d-1 may be required. Therefore, adolescent females at the time of puberty probably represent the optimal population for early prevention of osteoporosis with calcium. Young individuals must be in positive calcium balance to provide the calcium necessary for skeletal modelling and consolidation, but the degree of positive balance required to achieve peak bone mass and density is unknown. To assess calcium requirements in young individuals, and also to evaluate the determinants of calcium metabolism during the period of acquisition of peak bone mass, 487 calcium balances from previously published reports have been collected and analysed according to developmental phase and calcium intake. The results of this analysis showed that calcium intake and skeletal modelling/turnover are the most important determinants of calcium balance during growth. The highest requirements for calcium are during infancy and adolescence, and then during childhood and young adulthood. Infants (adequate vitamin D supply) and adolescents have higher calcium absorption than children and young adults to meet their high calcium requirements. Calcium absorption during the periods of rapid bone modelling/turnover is probably mediated by Nicolaysen's endogenous factor. Urinary calcium increases with age, and reaches a maximum by the end of puberty. The results also show that calcium intake has little effect on urinary calcium excretion during the period of most rapid skeletal formation: a weak correlation is present in children and young adults. On the basis of the above studies it was suggested that the RDA for calcium should be higher than currently established for children, adolescents, and young adults, in order to ensure a level of skeletal retention of calcium sufficient for maximal peak bone mass. In addition to nutrition, heredity (both parents) and endocrine factors (sexual development) appear to have profound effects on peak bone mass formation. Most of the skeletal mass will be accumulated by late adolescence, indicating early timing of peak bone mass.
Calcium and peak bone mass.
44586415
QUESTION Do clinical tests accurately diagnose rotator cuff pathology? DESIGN A systematic review of investigations into the diagnostic accuracy of clinical tests for rotator cuff pathology. PARTICIPANTS People with shoulder pain who underwent clinical testing in order to diagnose rotator cuff pathology. OUTCOME MEASURES The diagnostic accuracy of clinical tests was determined using likelihood ratios. RESULTS Thirteen studies met the inclusion criteria. The 13 studies evaluated 14 clinical tests in 89 separate evaluations of diagnostic accuracy. Only one evaluation, palpation for supraspinatus ruptures, resulted in significant positive and negative likelihood ratios. Eight of the 89 evaluations resulted in either significant positive or negative likelihood ratios. However, none of these eight positive or negative likelihood ratios were found in other studies. Of the 89 evaluations of clinical tests 71 (80%) did not result in either significant positive or negative likelihood ratio evaluations across different studies. CONCLUSION Overall, most tests for rotator cuff pathology were inaccurate and cannot be recommended for clinical use. At best, suspicion of a rotator cuff tear may be heightened by a positive palpation, combined Hawkins/painful arc/infraspinatus test, Napoleon test, lift-off test, belly-press test, or drop-arm test, and it may be reduced by a negative palpation, empty can test or Hawkins-Kennedy test.
Most clinical tests cannot accurately diagnose rotator cuff pathology: a systematic review.
44614949
OBJECTIVE To investigate the role of skeletal muscle (SkM) interleukin (IL)-6 in the regulation of adipose tissue metabolism. METHODS Muscle-specific IL-6 knockout (IL-6 MKO) and IL-6(loxP/loxP) (Floxed) mice were subjected to standard rodent diet (Chow), high-fat diet (HFD), or HFD in combination with exercise training (HFD ExTr) for 16 weeks. RESULTS Total fat mass increased (P < 0.05) in both genotypes with HFD. However, HFD IL-6 MKO mice had lower (P < 0.05) inguinal adipose tissue (iWAT) mass than HFD Floxed mice. Accordingly, iWAT glucose transporter 4 (GLUT4) protein content, 5'AMP activated protein kinase (AMPK)(Thr172) phosphorylation, and fatty acid synthase (FAS) mRNA content were lower (P < 0.05) in IL-6 MKO than Floxed mice on Chow. In addition, iWAT AMPK(Thr172) and hormone-sensitive lipase (HSL)(Ser565) phosphorylation as well as perilipin protein content was higher (P < 0.05) in HFD IL-6 MKO than HFD Floxed mice, and pyruvate dehydrogenase E1α (PDH-E1α) protein content was higher (P < 0.05) in HFD ExTr IL-6 MKO than HFD ExTr Floxed mice. CONCLUSIONS These findings indicate that SkM IL-6 affects iWAT mass through regulation of glucose uptake capacity as well as lipogenic and lipolytic factors.
Skeletal muscle interleukin‐6 regulates metabolic factors in iWAT during HFD and exercise training
44624045
BACKGROUND Few previous prospective studies have examined differences in incident ischemic heart disease (IHD) risk between vegetarians and nonvegetarians. OBJECTIVE The objective was to examine the association of a vegetarian diet with risk of incident (nonfatal and fatal) IHD. DESIGN A total of 44,561 men and women living in England and Scotland who were enrolled in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Oxford study, of whom 34% consumed a vegetarian diet at baseline, were part of the analysis. Incident cases of IHD were identified through linkage with hospital records and death certificates. Serum lipids and blood pressure measurements were available for 1519 non cases, who were matched to IHD cases by sex and age. IHD risk by vegetarian status was estimated by using multivariate Cox proportional hazards models. RESULTS After an average follow-up of 11.6 y, there were 1235 IHD cases (1066 hospital admissions and 169 deaths). Compared with nonvegetarians, vegetarians had a lower mean BMI [in kg/m(2); -1.2 (95% CI: -1.3, -1.1)], non-HDL-cholesterol concentration [-0.45 (95% CI: -0.60, -0.30) mmol/L], and systolic blood pressure [-3.3 (95% CI: -5.9, -0.7) mm Hg]. Vegetarians had a 32% lower risk (HR: 0.68; 95% CI: 0.58, 0.81) of IHD than did nonvegetarians, which was only slightly attenuated after adjustment for BMI and did not differ materially by sex, age, BMI, smoking, or the presence of IHD risk factors. CONCLUSION Consuming a vegetarian diet was associated with lower IHD risk, a finding that is probably mediated by differences in non-HDL cholesterol, and systolic blood pressure.
Risk of hospitalization or death from ischemic heart disease among British vegetarians and nonvegetarians: results from the EPIC-Oxford cohort study.
44629665
Multiple health priorities, limited human resources and logistical capacities, as well as expensive vaccines with limited funds available increase the need for evidence-based decision making in immunization programs. The aim of the Supporting Independent Immunization and Vaccine Advisory Committees (SIVAC) Initiative is to support countries in the establishment or strengthening of National Immunization Technical Advisory Groups (NITAGs) that provide recommendations on immunization policies and programs (e.g., vaccination schedules, improvements of routine immunization coverage, new vaccine introduction, etc.). SIVAC, a program funded by the Bill & Melinda Gates Foundation, is based on a country-driven, step-by-step process that ensures its support is tailored to country needs and emphasizes NITAG sustainability. SIVAC supports countries by reinforcing the capacities of the NITAG scientific and technical secretariat and by providing specific support activities established in consultation with the country and other international partners. Additionally, SIVAC and partners have built an electronic platform, the NITAG Resource Center, that provides information, tools, and briefings to NITAGs and the immunization community.
The Supporting Independent Immunization and Vaccine Advisory Committees (SIVAC) initiative: a country-driven, multi-partner program to support evidence-based decision making.
44640124
SIGNIFICANCE The extracellular matrix (ECM) fulfills essential functions in multicellular organisms. It provides the mechanical scaffold and environmental cues to cells. Upon cell attachment, the ECM signals into the cells. In this process, reactive oxygen species (ROS) are physiologically used as signalizing molecules. RECENT ADVANCES ECM attachment influences the ROS-production of cells. In turn, ROS affect the production, assembly and turnover of the ECM during wound healing and matrix remodeling. Pathological changes of ROS levels lead to excess ECM production and increased tissue contraction in fibrotic disorders and desmoplastic tumors. Integrins are cell adhesion molecules which mediate cell adhesion and force transmission between cells and the ECM. They have been identified as a target of redox-regulation by ROS. Cysteine-based redox-modifications, together with structural data, highlighted particular regions within integrin heterodimers that may be subject to redox-dependent conformational changes along with an alteration of integrin binding activity. CRITICAL ISSUES In a molecular model, a long-range disulfide-bridge within the integrin β-subunit and disulfide bridges within the genu and calf-2 domains of the integrin α-subunit may control the transition between the bent/inactive and upright/active conformation of the integrin ectodomain. These thiol-based intramolecular cross-linkages occur in the stalk domain of both integrin subunits, whereas the ligand-binding integrin headpiece is apparently unaffected by redox-regulation. FUTURE DIRECTIONS Redox-regulation of the integrin activation state may explain the effect of ROS in physiological processes. A deeper understanding of the underlying mechanism may open new prospects for the treatment of fibrotic disorders.
Redox-relevant aspects of the extracellular matrix and its cellular contacts via integrins.
44660616
OBJECTIVE To determine the prevalence of hypertension and pre-hypertension on the basis of the 2004 National High Blood Pressure Education Program Working Group guidelines in an adolescent school-screening population. STUDY DESIGN Cross-sectional assessment of blood pressure (BP) in 6790 adolescents (11-17 years) in Houston schools was conducted from 2003 to 2005. Initial measurements included height, weight, and 4 oscillometric BP readings. Repeat measurements were obtained on 2 subsequent occasions in students with persistently elevated BP. Final prevalence was adjusted for loss to follow-up and logistic regression used to assess risk factors. RESULTS BP distribution at initial screen was 81.1% normal, 9.5% pre-hypertension, and 9.4% hypertension (8.4% Stage 1; 1% Stage 2). Prevalence after 3 screenings was 81.1% normal, 15.7% pre-hypertension, and 3.2% hypertension (2.6% Stage 1; 0.6% Stage 2). Hypertension and pre-hypertension increased with increasing body mass index. Sex, race, and classification as either at-risk for overweight or overweight were independently associated with pre-hypertension. Only classification as overweight was associated with hypertension. CONCLUSIONS Application of new classification guidelines for adolescents with elevated BP reveals approximately 20% are at risk for hypertension. Further research determining the significance of each BP category and refining definitions to account for BP variability is warranted.
Prevalence of hypertension and pre-hypertension among adolescents.
44672703
BACKGROUND & AIMS Various commensal enteric and potentially pathogenic bacteria may be involved in the pathogenesis of inflammatory bowel diseases (IBD). We compared the risk of IBD between a cohort of patients with documented Salmonella or Campylobacter gastroenteritis and an age- and gender-matched control group from the same population in Denmark. METHODS We identified 13,324 patients with Salmonella/Campylobacter gastroenteritis from laboratory registries in North Jutland and Aarhus counties, Denmark, from 1991 through 2003, and 26,648 unexposed controls from the same counties. Of these, 176 exposed patients with IBD before the infection, their 352 unexposed controls, and 80 unexposed individuals with IBD before the Salmonella/Campylobacter infection were excluded. The final study cohort of 13,148 exposed and 26,216 unexposed individuals were followed for up to 15 years (mean, 7.5 years). RESULTS A first-time diagnosis of IBD was reported in 107 exposed (1.2%) and 73 unexposed individuals (0.5%). By age, gender, and comorbidity adjusted Cox proportional hazards regression analysis, the hazard ratio (95% confidence interval) for IBD was 2.9 (2.2-3.9) for the whole period and 1.9 (1.4-2.6) if the first year after the Salmonella/Campylobacter infection was excluded. The increased risk in exposed subjects was observed throughout the 15-year observation period. The increased risk was similar for Salmonella (n = 6463) and Campylobacter (n = 6685) and for a first-time diagnosis of Crohn's disease (n = 47) and ulcerative colitis (n = 133). CONCLUSIONS In our population-based cohort study with complete follow-up, an increased risk of IBD was demonstrated in individuals notified in laboratory registries with an episode of Salmonella/Campylobacter gastroenteritis.
Increased short- and long-term risk of inflammatory bowel disease after salmonella or campylobacter gastroenteritis.
44674301
A long-term cell culture epithelioid cell line was established from a recurrent squamous carcinoma of the nasopharynx of a Chinese male 17 1/2 years after radiation therapy. The cell line, designated NPC/HK1, has been passed 72 times over a period 1 year. The cells have been shown by light and electron microscopies to be of the squamous epithelial type. When they were transplanted subcutaneously into the back of athymic nude BALB/c (nu/nu) mice, tumors developed at the sites of inoculation, which on histological examination were shown to be well-differentiated squamous carcinomas, similar in morphology to the recurrent human tumor from which they were derived. Karyotypic analysis of cells from the cell line demonstrates an aneuploid human type with a modal chromosome number of 74 with both numerical and structural aberrations. Viral particles or Epstein-Barr viral nuclear antigen (EBNA) has not been demonstrated in the cells from the primary culture or several of the subcultures tested. The presence of EBNA in touch smears prepared from the biopsy tissue was inconclusive. Infection of the subcultured cells with EBV from P3HR1 and B95-8 cells was unsuccessful.
Establishment of a cell line (NPC/HK1) from a differentiated squamous carcinoma of the nasopharynx.
44693226
Many studies have shown that caloric restriction (40%) decreases mitochondrial reactive oxygen species (ROS) generation in rodents. Moreover, we have recently found that 7 weeks of 40% protein restriction without strong caloric restriction also decreases ROS production in rat liver. This is interesting since it has been reported that protein restriction can also extend longevity in rodents. In the present study we have investigated the possible role of dietary lipids in the effects of caloric restriction on mitochondrial oxidative stress. Using semipurified diets, the ingestion of lipids in male Wistar rats was decreased by 40% below controls, while the other dietary components were ingested at exactly the same level as in animals fed ad libitum. After 7 weeks of treatment the liver mitochondria of lipid-restricted animals showed significant increases in oxygen consumption with complex I-linked substrates (pyruvate/malate and glutamate/malate). Neither mitochondrial H(2)O(2) production nor oxidative damage to mitochondrial or nuclear DNA was modified in lipid-restricted animals. Oxidative damage to mitochondrial DNA was one order of magnitude higher than that of nuclear DNA in both dietary groups. These results deny a role for lipids and reinforce the possible role of dietary proteins as being responsible for the decrease in mitochondrial ROS production and DNA damage in caloric restriction.
Effect of lipid restriction on mitochondrial free radical production and oxidative DNA damage.
44724517
Although myeloid cell activation is requisite for an optimal innate immune response, this process must be tightly controlled to prevent collateral host tissue damage. Kruppel-like factor 2 (KLF2) is a potent regulator of myeloid cell proinflammatory activation. As an approximately 30% to 50% reduction in KLF2 levels has been observed in human subjects with acute or chronic inflammatory disorders, we studied the biological response to inflammation in KLF2(+/-) mice. Herein, we show that partial deficiency of KLF2 modulates the in vivo response to acute (sepsis) and subacute (skin) inflammatory challenge. Mechanistically, we link the anti-inflammatory effects of KLF2 to the inhibition of NF-κB transcriptional activity. Collectively, the observations provide biologically relevant insights into KLF2-mediated modulation of these inflammatory processes that could potentially be manipulated for therapeutic gain.
Kruppel-like factor 2 is a transcriptional regulator of chronic and acute inflammation.
44737533
METHODS To define potential common features of simian immunodeficiency virus (SIV) infections in different naturally infected host species, we compared the dynamics of viral replication in 31 African green monkeys (10 sabeus, 15 vervets and seven Caribbean AGMs), 14 mandrills and three sooty mangabeys (SMs) that were experimentally infected with their species-specific viruses. RESULTS After infection, these SIVs replicated rapidly reaching viral loads (VLs) of 10(5)-10(9) copies/ml of plasma between days 9-14 post-infection (p.i). Set point viremia was established between days 42 and 60 p.i., with levels of approximately 10(5)-10(6) copies/ml in SM and mandrills, and lower levels (10(3)-10(5) copies/ml) in AGMs. VL during the chronic phase did not correlate with viral genome structure: SIVmnd-2 (a vpx-containing virus) and SIVmnd-1 (which does not contain vpu or vpx) replicated to similar levels in mandrills. VL was dependent on virus strain: vervets infected with three different viral strains showed different patterns of viral replication. The pattern of viral replication of SIVagm.sab, which uses both CCR5 and CXCR4 co-receptors was similar to those of the other viruses. CONCLUSIONS Our results show a common pattern of SIV replication in naturally and experimentally infected hosts. This is similar overall to that observed in pathogenic SIV infection of macaques. This result indicates that differences in clinical outcome between pathogenic and non-pathogenic infections rely on host responses rather than the characteristics of the virus itself.
Simian immunodeficiency viruses replication dynamics in African non-human primate hosts: common patterns and species-specific differences.
44801733
The zinc-finger transcription factor KLF2 transduces the physical forces exerted by blood flow into molecular signals responsible for a wide range of biological responses. Following its initial recognition as a flow-responsive endothelial transcription factor, KLF2 is now known to be expressed in a range of cell types and to participate in a number of processes during development and disease such as endothelial homeostasis, vasoregulation, vascular growth/remodeling, and inflammation. In this review, we summarize the current understanding about KLF2 with a focus on its effects on vascular biology.
The role of the transcription factor KLF2 in vascular development and disease.
44827480
BACKGROUND Few data exist about the implementation of contemporary oral antiplatelet treatment guidelines in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). METHODS GReek AntiPlatelet rEgistry (GRAPE), initiated on January 2012, is a prospective, observational, multicenter cohort study focusing on contemporary use of P2Y12 inhibitors. In 1434 patients we evaluated appropriateness of P2Y12 selection initially and at discharge by applying an eligibility-assessing algorithm based on P2Y12 inhibitors' contraindications/specific warnings and precautions. RESULTS Appropriate, less preferable and inappropriate P2Y12 inhibitor selections were made initially in 45.8%, 47.2% and 6.6% and at discharge in 64.1%, 29.2% and 6.6% of patients, respectively. The selection of clopidogrel was most commonly less preferable, both initially (69.7%) and at discharge (75.6%). Appropriate selection of newer agents was high initially (79.2%-82.8%), with further increase as selection at discharge (89.4%-89.8%). Inappropriate selection of the newer agents was 17.2%-20.8% initially, decreasing to 10.2%-10.6% at discharge. Conditions and co-medications related to increased bleeding risk, presentation with ST elevation myocardial infarction and the absence of reperfusion within the first 24h were the most powerful predictors of appropriate P2Y12 selection initially, whereas age ≥75 years, conditions and co-medications related to increased bleeding risk and regional trends mostly affected appropriate P2Y12 selection at discharge. CONCLUSIONS In GRAPE, adherence with the recently released guidelines on oral antiplatelet therapy was satisfactory. Clopidogrel was most commonly used as a less preferable selection, while prasugrel or ticagrelor selection was mostly appropriate. Certain factors may predict initial and at discharge guideline implementation. Clinical Trial Registration-clinicaltrials.gov Identifier: NCT01774955 http://clinicaltrials.gov/.
Implementation of contemporary oral antiplatelet treatment guidelines in patients with acute coronary syndrome undergoing percutaneous coronary intervention: a report from the GReek AntiPlatelet rEgistry (GRAPE).
44830890
OBJECTIVE To investigate the frequency of depressive and anxiety disorders in patients with chronic daily headache. BACKGROUND There is a lack of data in the literature on the extent of psychiatric comorbidity in patients with different subtypes of chronic daily headache. METHODS We recruited consecutive patients with chronic daily headache seen in a headache clinic from November 1998 to December 1999. The subtypes of chronic daily headache were classified according to the criteria proposed by Silberstein et al. A psychiatrist evaluated the patients according to the structured Mini-International Neuropsychiatric Interview to assess the comorbidity of depressive and anxiety disorders. RESULTS Two hundred sixty-one patients with chronic daily headache were recruited. The mean age was 46 years, and 80% were women. Transformed migraine was diagnosed in 152 patients (58%) and chronic tension-type headache in 92 patients (35%). Seventy-eight percent of patients with transformed migraine had psychiatric comorbidity, including major depression (57%), dysthymia (11%), panic disorder (30%), and generalized anxiety disorder (8%). Sixty-four percent of patients with chronic tension-type headache had psychiatric diagnoses, including major depression (51%), dysthymia (8%), panic disorder (22%), and generalized anxiety disorder (1%). The frequency of anxiety disorders was significantly higher in patients with transformed migraine after controlling for age and sex (P =.02). Both depressive and anxiety disorders were significantly more frequent in women. CONCLUSION Psychiatric comorbidity, especially major depression and panic disorders, was highly prevalent in patients with chronic daily headache seen in a headache clinic. These results demonstrate that women and patients with transformed migraine are at higher risk of psychiatric comorbidity.
Comorbidity of depressive and anxiety disorders in chronic daily headache and its subtypes.
44935041
Although most cytokines are studied for biological effects after engagement of their specific cell surface membrane receptors, increasing evidence suggests that some function in the nucleus. In the present study, the precursor form of IL-1alpha was overexpressed in various cells and assessed for activity in the presence of saturating concentrations of IL-1 receptor antagonist to prevent receptor signaling. Initially diffusely present in the cytoplasm of resting cells, IL-1alpha translocated to the to nucleus after activation by endotoxin, a Toll-like receptor ligand. The IL-1alpha precursor, but not the C-terminal mature form, activated the transcriptional machinery in the GAL4 system by 90-fold; a 50-fold increase was observed using only the IL-1alpha propiece, suggesting that transcriptional activation was localized to the N terminus where the nuclear localization sequence resides. Under conditions of IL-1 receptor blockade, intracellular overexpression of the precursor and propiece forms of IL-1alpha were sufficient to activate NF-kappaB and AP-1. Stable transfectants overproducing precursor IL-1alpha released the cytokines IL-8 and IL-6 but also exhibited a significantly lower threshold of activation to subpicomolar concentrations of tumor necrosis factor alpha or IFN-gamma. Thus, intracellular functions of IL-1alpha might play an unforeseen role in the genesis of inflammation. During disease-driven events, the cytosolic precursor moves to the nucleus, where it augments transcription of proinflammatory genes. Because this mechanism of action is not affected by extracellular inhibitors, reducing intracellular functions of IL-1alpha might prove beneficial in some inflammatory conditions.
The precursor form of IL-1alpha is an intracrine proinflammatory activator of transcription.
44947611
We have used NMR spectroscopy to determine the solution structure of protein AAH26994.1 from Mus musculus and propose that it represents the first three-dimensional structure of a ubiquitin-related modifier 1 (Urm1) protein. Amino acid sequence comparisons indicate that AAH26994.1 belongs to the Urm1 family of ubiquitin-like modifier proteins. The best characterized member of this family has been shown to be involved in nutrient sensing, invasive growth, and budding in yeast. Proteins in this family have only a weak sequence similarity to ubiquitin, and the structure of AAH26994.1 showed a much closer resemblance to MoaD subunits of molybdopterin synthases (known structures are of three bacterial MoaD proteins with 14%-26% sequence identity to AAH26994.1). The structures of AAH26994.1 and the MoaD proteins each contain the signature ubiquitin secondary structure fold, but all differ from ubiquitin largely in regions outside of this fold. This structural similarity bolsters the hypothesis that ubiquitin and ubiquitin-related proteins evolved from a protein-based sulfide donor system of the molybdopterin synthase type.
Three-dimensional structure of the AAH26994.1 protein from Mus musculus, a putative eukaryotic Urm1.
45015767
BACKGROUND Adenocarcinoma of the endometrium is the most common gynecologic malignancy in the United States, accounting for approximately 36,000 diagnoses of invasive carcinoma annually. The most common histologic type, endometrioid adenocarcinoma (EC), accounts for 75-80% of patients. The objective of this work was to estimate the prevalence of concurrent carcinoma in women with a biopsy diagnosis of the precursor lesion, atypical endometrial hyperplasia (AEH). METHODS This prospective cohort study included women who had a community diagnosis of AEH. Diagnostic biopsy specimens were reviewed independently by three gynecologic pathologists who used International Society of Gynecologic Pathologists/World Health Organization criteria. Study participants underwent hysterectomy within 12 weeks of entry onto protocol without interval treatment. The hysterectomy slides also were reviewed by the study pathologists, and their findings were used in the subsequent analyses. RESULTS Between November 1998 and June 2003, 306 women were enrolled on the study. Of these, 17 women were not included in the analysis: Two patients had unreadable slides because of poor processing or insufficient tissue, 2 patients had only slides that were not endometrial, the slides for 5 patients were not available for review, and 8 of the hysterectomy specimens were excluded because they showed evidence of interval intervention, either progestin effect or ablation. In total, 289 patients were included in the current analysis. The study panel review of the AEH biopsy specimens was interpreted as follows: 74 of 289 specimens (25.6%) were diagnosed as less than AEH, 115 of 289 specimens (39.8%) were diagnosed as AEH, and 84 of 289 specimens (29.1%) were diagnosed as endometrial carcinoma. In 5.5% (16 of 289 specimens), there was no consensus on the biopsy diagnosis. The rate of concurrent endometrial carcinoma for analyzed specimens was 42.6% (123 of 289 specimens). Of these, 30.9% (38 of 123 specimens) were myoinvasive, and 10.6% (13 of 123 specimens) involved the outer 50% of the myometrium. Among the women who had hysterectomy specimens with carcinoma, 14 of 74 women (18.9%) had a study panel biopsy consensus diagnosis of less than AEH, 45 of 115 women (39.1%) had a study panel biopsy consensus diagnosis of AEH, and 54 of 84 women (64.3%) had a study panel diagnosis of carcinoma. Among women who had no consensus in their biopsy diagnosis, 10 of 16 women (62.5%) had carcinoma in their hysterectomy specimens. CONCLUSIONS The prevalence of endometrial carcinoma in patients who had a community hospital biopsy diagnosis of AEH was high (42.6%). When considering management strategies for women who have a biopsy diagnosis of AEH, clinicians and patients should take into account the considerable rate of concurrent carcinoma.
Concurrent endometrial carcinoma in women with a biopsy diagnosis of atypical endometrial hyperplasia: a Gynecologic Oncology Group study.
45027320
BACKGROUND The aim of this study was to examine the clustering of four major lifestyle risk factors (smoking, heavy drinking, lack of fruit and vegetables consumption, and lack of physical activity), and to examine the variation across different socio-demographic groups in the English adult population. METHODS The study population was derived from the 2003 Health Survey for England (n=11,492). Clustering was examined by comparing the observed and expected prevalence of the different possible combinations. A multinomial multilevel regression model was conducted to examine the socio-demographic variation in the clustering of the four risk factors. RESULTS The study found that, when using British health recommendations, a majority of the English population have multiple lifestyle risk factors at the same time. Clustering was found at both ends of the lifestyle spectrum and was more pronounced for women than for men. Overall, multiple risk factors were more prevalent among men, lower social class households, singles, and people who are economically inactive, but less prevalent among home owners and older age groups. CONCLUSIONS The clustering of multiple risk factors provides support for multiple-behavior interventions as opposed to single-behavior interventions.
The prevalence and clustering of four major lifestyle risk factors in an English adult population.
45096063
IL-17 is an inflammatory cytokine produced primarily by a unique lineage of CD4 T cells that plays critical roles in the pathogenesis of multiple autoimmune diseases. IL-17RA is a ubiquitously expressed receptor that is essential for IL-17 biologic activity. Despite widespread receptor expression, the activity of IL-17 is most classically defined by its ability to induce the expression of inflammatory cytokines, chemokines, and other mediators by stromal cells. The lack of IL-17 responsiveness in mouse stromal cells genetically deficient in IL-17RA is poorly complemented by human IL-17RA, suggesting the presence of an obligate ancillary component whose activity is species specific. This component is IL-17RC, a distinct member of the IL-17R family. Thus, the biologic activity of IL-17 is dependent on a complex composed of IL-17RA and IL-17RC, suggesting a new paradigm for understanding the interactions between the expanded family of IL-17 ligands and their receptors.
Cutting edge: interleukin 17 signals through a heteromeric receptor complex.
45143088
Long non-coding RNAs (lncRNAs) are involved in regulating chromatin modifications, gene transcription, mRNA translation, and protein function. We recently reported a high variation in the basal expression levels of a panel of lncRNAs in HeLa and MCF-7 cells and their differential response to DNA damage induction. Here, we hypothesized that lncRNA molecules with different cellular expression may have a differential abundance in secreted exosomes, and their exosome levels would reflect cellular response to DNA damage. MALAT1, HOTAIR, lincRNA-p21, GAS5, TUG1, CCND1-ncRNA in exosomes secreted from cultured cells were characterized. A different expression pattern of lncRNAs in exosomes was seen compared to cells. RNA molecules with relative low expression levels (lincRNA-p21, HOTAIR, ncRNA-CCND1) were highly enriched in exosomes. TUG1 and GAS5 levels were moderately elevated in exosomes, whereas MALAT1--which was the most abundant molecule in cells--was present at levels comparable to its cellular levels. lincRNA-p21 and ncRNA-CCND1 were the main molecules; exosome levels of them best reflect the change of their cellular levels upon exposure of the cells to bleomycin-induced DNA damage. In conclusion, we provide evidence that lncRNAs have a differential abundance in exosomes, indicating a selective loading.
Long non-coding RNAs with low expression levels in cells are enriched in secreted exosomes.
45153864
Treatment with second-generation antipsychotic agents such as olanzapine frequently results in metabolic adverse effects, e.g. hyperphagia, weight gain and dyslipidaemia in patients of both genders. The molecular mechanisms underlying metabolic adverse effects are still largely unknown, and studies in rodents represent an important approach in their exploration. However, the validity of the rodent model is hampered by the fact that antipsychotics induce weight gain in female, but not male, rats. When administered orally, the short half-life of olanzapine in rats prevents stable plasma concentrations of the drug. We recently showed that a single intramuscular injection of long-acting olanzapine formulation yields clinically relevant plasma concentrations accompanied by several dysmetabolic features in the female rat. In the current study, we show that depot injections of 100-250 mg/kg olanzapine yielded clinically relevant plasma olanzapine concentrations also in male rats. In spite of transient hyperphagia, however, olanzapine resulted in weight loss rather than weight gain. The resultant negative feed efficiency was accompanied by a slight elevation of thermogenesis markers in brown adipose tissue for the highest olanzapine dose, but the olanzapine-related reduction in weight gain remains to be explained. In spite of the absence of weight gain, an olanzapine dose of 200mg/kg or above induced significantly elevated plasma cholesterol levels and pronounced activation of lipogenic gene expression in the liver. These results confirm that olanzapine stimulates lipogenic effects, independent of weight gain, and raise the possibility that endocrine factors may influence gender specificity of metabolic effects of antipsychotics in the rat.
Olanzapine depot exposure in male rats: Dose-dependent lipogenic effects without concomitant weight gain.
45154987
The melanocortin receptor 4 (MC4R) is a well-established mediator of body weight homeostasis. However, the neurotransmitter(s) that mediate MC4R function remain largely unknown; as a result, little is known about the second-order neurons of the MC4R neural pathway. Single-minded 1 (Sim1)-expressing brain regions, which include the paraventricular nucleus of hypothalamus (PVH), represent key brain sites that mediate melanocortin action. We conditionally restored MC4R expression in Sim1 neurons in the background of Mc4r-null mice. The restoration dramatically reduced obesity in Mc4r-null mice. The anti-obesity effect was completely reversed by selective disruption of glutamate release from those same Sim1 neurons. The reversal was caused by lower energy expenditure and hyperphagia. Corroboratively, selective disruption of glutamate release from adult PVH neurons led to rapid obesity development via reduced energy expenditure and hyperphagia. Thus, this study establishes glutamate as the primary neurotransmitter that mediates MC4Rs on Sim1 neurons in body weight regulation.
Glutamate mediates the function of melanocortin receptor 4 on Sim1 neurons in body weight regulation.
45166582
We review the cellular mechanisms implicated in cholesterol trafficking and distribution. Recent studies have provided new information about the distribution of sterols within cells, including analysis of its transbilayer distribution. The cholesterol interaction with other lipids and its engagement in various trafficking processes will determine its proper level in a specific membrane; making the cholesterol distribution uneven among the various intracellular organelles. The cholesterol content is important since cholesterol plays an essential role in membranes by controlling their physicochemical properties as well as key cellular events such as signal transduction and protein trafficking. Cholesterol movement between cellular organelles is highly dynamic, and can be achieved by vesicular and non-vesicular processes. Various studies have analyzed the proteins that play a significant role in these processes, giving us new information about the relative importance of these two trafficking pathways in cholesterol transport. Although still poorly characterized in many trafficking routes, several potential sterol transport proteins have been described in detail; as a result, molecular mechanisms for sterol transport among membranes start to be appreciated.
Intracellular sterol dynamics.
45199834
Abstract Intact HeLa cells can bind virions of poliovirus type 1 and can subsequently convert them to altered particles by incubation at 37°. Altered particles sediment more slowly than virions, have lost VP-4, and are disrupted by sodium dodecyl sulfate, but their RNA is intact and ribonuclease insensitive. These characteristics allow assay of altered particles and of particles that have released their RNA, using nuclease digestion with or without sodium dodecyl sulfate treatment. With this simple assay procedure, quantitative parameters of binding and alteration can be measured. The binding-altering activity can be localized in plasma membranes, and pure membranes can be shown to carry out alteration. The membrane-bound activity is abolished by proteases and by nonionic detergents. Only altered particles are formed by membranes; release of RNA is not caused by membranes but is caused by intact cells. Binding and alteration are processes that are closely associated; it is possible that alteration is a consequence of binding by multiple receptors in a fluid membrane.
A plasma membrane component able to bind and alter virions of poliovirus type 1: studies on cell-free alteration using a simplified assay.
45200347
Decreasing costs of next-generation sequencing (NGS) experiments have made a wide range of genomic questions open for study with nonmodel organisms. However, experimental designs and analysis of NGS data from less well-known species are challenging because of the lack of genomic resources. In this work, we investigate the performance of alternative experimental designs and bioinformatics approaches in estimating variability and neutrality tests based on the site-frequency-spectrum (SFS) from individual resequencing data. We pay particular attention to challenges faced in the study of nonmodel organisms, in particular the absence of a species-specific reference genome, although phylogenetically close genomes are assumed to be available. We compare the performance of three alternative bioinformatics approaches – genotype calling, genotype–haplotype calling and direct estimation without calling genotypes. We find that relying on genotype calls provides biased estimates of population genetic statistics at low to moderate read depth (2–8X). Genotype–haplotype calling returns more accurate estimates irrespective of the divergence to the reference genome, but requires moderate depth (8–20X). Direct estimation without calling genotypes returns the most accurate estimates of variability and of most SFS tests investigated, including at low read depth (2–4X). Studies without species-specific reference genome should thus aim for low read depth and avoid genotype calling whenever individual genotypes are not essential. Otherwise, aiming for moderate to high depth at the expense of number of individuals, and using genotype–haplotype calling, is recommended.
Resequencing studies of nonmodel organisms using closely related reference genomes: optimal experimental designs and bioinformatics approaches for population genomics.
45218443
The hemoglobinopathies are probably the world's most common genetic diseases: The World Health Organization has estimated that at least 5% of the population are carriers for one or other of the most serious forms, the alpha- and beta-thalassemias and the structural variant hemoglobins S, C, and E, which are found at polymorphic frequencies in many countries. All these hemoglobinopathies are believed to provide protection against malaria, and it is thought that, in malarial regions of the world, natural selection has been responsible for elevating and maintaining their gene frequencies, an idea first proposed 50 years ago by J.B.S. Haldane. Epidemiological studies undertaken in the 1950s on hemoglobin S in Africa provided support for the "malaria hypothesis," but until recently it has proved extremely difficult to verify it for the thalassemias. The application of molecular methods has, however, provided new opportunities to address this old question. Population and molecular genetic analysis of thalassemia variants, and microepidemiological studies of the relationship between alpha-thalassemia and malaria in the southwest Pacific, have provided unequivocal evidence for protection. Surprisingly, some of this protection appears to derive from enhanced susceptibility in very young thalassemic children to both Plasmodium falciparum and, especially, P. vivax, and this early exposure appears to provide the basis for better protection in later life.
Thalassemia and malaria: new insights into an old problem.
45244537
Evaluation of testicular functions (production of sperm and androgens) is an important aspect of preclinical safety assessment and testicular toxicity is comparatively far more common than ovarian toxicity. This chapter focuses (1) on the histological sequelae of disturbed reproductive endocrinology in rat, dog and nonhuman primates and (2) provides a review of our current understanding of the roles of gonadotropins and androgens. The response of the rodent testis to endocrine disturbances is clearly different from that of dog and primates with different germ cell types and spermatogenic stages being affected initially and also that the end-stage spermatogenic involution is more pronounced in dog and primates compared to rodents. Luteinizing hormone (LH)/testosterone and follicle-stimulating hormone (FSH) are the pivotal endocrine factors controlling testicular functions. The relative importance of either hormone is somewhat different between rodents and primates. Generally, however, both LH/testosterone and FSH are necessary for quantitatively normal spermatogenesis, at least in non-seasonal species.
Endocrine control of spermatogenesis: Role of FSH and LH/ testosterone.
45276789
This survey of regional neonatal intensive care units determined a prevalence of 38 per 1000 neonates who sustained an extravasation injury that caused skin necrosis. Most injuries occurred in infants of 26 weeks gestation or less, with parenteral nutrition infused through intravenous cannulae. Common treatments were exposing wounds to the air, infiltration with hyaluronidase and saline, and occlusive dressings.
Extravasation injuries on regional neonatal units.
45287266
Hepatitis C virus (HCV) nonstructural protein 3-4A (NS3-4A) is a complex composed of NS3 and its cofactor NS4A. It harbours serine protease as well as NTPase/RNA helicase activities and is essential for viral polyprotein processing, RNA replication and virion formation. Specific inhibitors of the NS3-4A protease significantly improve sustained virological response rates in patients with chronic hepatitis C when combined with pegylated interferon-α and ribavirin. The NS3-4A protease can also target selected cellular proteins, thereby blocking innate immune pathways and modulating growth factor signalling. Hence, NS3-4A is not only an essential component of the viral replication complex and prime target for antiviral intervention but also a key player in the persistence and pathogenesis of HCV. This review provides a concise update on the biochemical and structural aspects of NS3-4A, its role in the pathogenesis of chronic hepatitis C and the clinical development of NS3-4A protease inhibitors.
Nonstructural protein 3-4A: the Swiss army knife of hepatitis C virus.
45336190
OBJECTIVE To evaluate the safety, tolerability, and amyloid beta (Abeta) response to the gamma-secretase inhibitor LY450139 in Alzheimer disease. DESIGN Multicenter, randomized, double-blind, dose-escalation, placebo-controlled trial. SETTING Community-based clinical research centers. Patients Fifty-one individuals with mild to moderate Alzheimer disease were randomized to receive placebo (n=15) or LY450139 (100 mg [n=22] or 140 mg [n=14]), with 43 completing the treatment phase. Intervention The LY450139 groups received 60 mg/d for 2 weeks, then 100 mg/d for 6 weeks, and then either 100 or 140 mg/d for 6 additional weeks. MAIN OUTCOME MEASURES Primary outcome measures were adverse events, plasma and cerebrospinal fluid Abeta levels, vital signs, electrocardiographic data, and laboratory safety test results. Secondary outcome measures included the Alzheimer's Disease Assessment Scale cognitive subscale and the Alzheimer's Disease Cooperative Study Activities of Daily Living Scale. RESULTS Group differences were seen in skin and subcutaneous tissue concerns (P=.05), including 3 possible drug rashes and 3 reports of hair color change in the treatment groups. There were 3 adverse event-related discontinuations, including 1 transient bowel obstruction. The plasma Abeta(40) concentration was reduced by 58.2% for the 100-mg group and 64.6% for the 140-mg group (P<.001). No significant reduction was seen in cerebrospinal fluid Abeta levels. No group differences were seen in cognitive or functional measures. CONCLUSIONS LY450139 was generally well tolerated at doses of up to 140 mg/d for 14 weeks, with several findings indicating the need for close clinical monitoring in future studies. Decreases in plasma Abeta concentrations were consistent with inhibition of gamma-secretase. Trial Registration clinicaltrials.gov Identifier: NCT00244322.
Phase 2 safety trial targeting amyloid beta production with a gamma-secretase inhibitor in Alzheimer disease.
45341480
AIM/PURPOSE The aim of this study was to compare clinical outcome of children with scald burns treated with a hydrofiber dressing (Aquacel(®), Convatec Inc.) with the former standard of care with silver sulfadiazine (Flammazine(®); Solvay Pharmaceuticals), considering surgical intervention and length of stay (LOS). METHODS A retrospective study of all consecutive children from zero to four years with primary scald burns up to 10% admitted to the Burn Centre of the Maasstad Hospital Rotterdam between January 1987 and January 2010 were reviewed. For data collection a prospective computerized database was used. For comparison the study period was divided into two periods representing the period before and after the introduction of the hydrofiber dressing (HFD), respectively 1987-1999 (period 1) and 1999-2010 (period 2). RESULTS Over the whole study period 27.3% of 502 patients treated with silver sulfadiazine (Ag-SD) underwent surgery, while before the introduction of HFD 30.5% of 338 Ag-SD treated patients were operated upon. After the introduction of the HFD 20.7% of 164 patients treated with Ag-SD eventually underwent skin grafting, a significant difference with the 11.6% of 302 patients whose wounds were dressed with HFD (p<0.01). CONCLUSIONS Compared to silver sulfadiazine treatment a reduced number of surgical interventions was observed in mixed partial thickness scald burns up to 10% TBSA burned in children aged 0-4 years after the introduction of hydrofiber dressings. The mode of treatment with this wound dressing also limited hospital length of stay.
Reduction in skin grafting after the introduction of hydrofiber dressings in partial thickness burns: a comparison between a hydrofiber and silver sulphadiazine.
45364685
The effects of a set of stress treatments on gene expression of Chironomus thummi salivary gland cells have been analyzed. Among the treatments assayed, only during recovery from carbon dioxide have we observed a response similar to that previously described after heat-shock treatment: induction of the heat-shock puffs and synthesis of the heat-shock polypeptides. In these conditions, puffing and transcription of telomeric regions were observed, which led to the appearance of the temperature-inducible telomeric Balbiani ring T-BR-III. Other treatments failed to induce the heat-shock response, despite promoting real stress conditions to C. thummi larvae or salivary gland cells.
Induction of the heat-shock response by carbon dioxide in Chironomus thummi.
45401535
Despite advances in medical device fabrication and antimicrobial treatment therapies, fungal-bacterial polymicrobial peritonitis remains a serious complication for surgery patients, those on peritoneal dialysis, and the critically ill. Using a murine model of peritonitis, we have demonstrated that monomicrobial infection with Candida albicans or Staphylococcus aureus is nonlethal. However, coinfection with these same doses leads to a 40% mortality rate and increased microbial burden in the spleen and kidney by day 1 postinfection. Using a multiplex enzyme-linked immunosorbent assay, we have also identified a unique subset of innate proinflammatory cytokines (interleukin-6, granulocyte colony-stimulating factor, keratinocyte chemoattractant, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1α) that are significantly increased during polymicrobial versus monomicrobial peritonitis, leading to increased inflammatory infiltrate into the peritoneum and target organs. Treatment of coinfected mice with the cyclooxygenase (COX) inhibitor indomethacin reduces the infectious burden, proinflammatory cytokine production, and inflammatory infiltrate while simultaneously preventing any mortality. Further experiments demonstrated that the immunomodulatory eicosanoid prostaglandin E2 (PGE2) is synergistically increased during coinfection compared to monomicrobial infection; indomethacin treatment also decreased elevated PGE2 levels. Furthermore, addition of exogenous PGE2 into the peritoneal cavity during infection overrode the protection provided by indomethacin and restored the increased mortality and microbial burden. Importantly, these studies highlight the ability of fungal-bacterial coinfection to modulate innate inflammatory events with devastating consequences to the host.
Candida albicans-Staphylococcus aureus polymicrobial peritonitis modulates host innate immunity.
45408403
The frog Xenopus laevis has provided significant insights into developmental and cellular processes. However, X. laevis has an allotetraploid genome precluding its use in forward genetic analysis. Genetic analysis may be applicable to Xenopus (Silurana) tropicalis, which has a diploid genome and a shorter generation time. Here, we show that many tools for the study of X. laevis development can be applied to X. tropicalis. By using the developmental staging system of Nieuwkoop and Faber, we find that X. tropicalis embryos develop at similar rates to X. laevis, although they tolerate a narrower range of temperatures. We also show that many of the analytical reagents available for X. laevis can be effectively transferred to X. tropicalis. The X. laevis protocol for whole-mount in situ hybridization to mRNA transcripts can be successfully applied to X. tropicalis without alteration. Additionally, X. laevis probes often work in X. tropicalis--alleviating the immediate need to clone the X. tropicalis orthologs before initiating developmental studies. Antibodies that react against X. laevis proteins can effectively detect the X. tropicalis protein by using established immunohistochemistry procedures. Antisense morpholino oligonucleotides (MOs) offer a new alternative to study loss of gene activity during development. We show that MOs function in X. tropicalis. Finally, X. tropicalis offers the possibility for forward genetics and genomic analysis.
Techniques and probes for the study of Xenopus tropicalis development.
45414636
Previous reports have suggested that the protooncogene c-myb participates in T cell development in the thymus and mature T cell proliferation. We have generated two T cell-specific c-myb knockout mouse models, myb/LckCre and myb/CD4Cre. We have demonstrated that c-myb is required for the development of thymocytes at the DN3 stage, for survival and proliferation of double-positive thymocytes, for differentiation of single-positive CD4 and CD8 T cells, and for the proliferative responses of mature T cells. In addition, our data show that c-myb is directly involved in the formation of double-positive CD4+CD8+CD25+, CD4+CD25+, and CD8+CD25+ T cells, developmental processes that may imply a role for c-myb in autoimmune dysfunction.
Requirement of c-myb in T cell development and in mature T cell function.
45447613
OBJECTIVE Previous studies have shown increases in ambulatory short-term blood pressure (BP) variability to be related to cardiovascular disease. In this study, we examined whether an angiotensin II type 1 receptor blocker losartan would improve ambulatory short-term BP variability in hypertensive patients on hemodialysis. METHODS Forty hypertensive patients on hemodialysis therapy were randomly assigned to the losartan treatment group (n=20) or the control treatment group (n=20). At baseline and 6 and 12 months after the treatment, 24-h ambulatory BP monitoring was performed. Echocardiography and measurements of brachial-ankle pulse wave velocity (baPWV) and biochemical parameters were also performed before and after therapy. RESULTS After 6- and 12-months of treatment, nighttime short-term BP variability, assessed on the basis of the coefficient of variation of ambulatory BP, was significantly decreased in the losartan group, but remained unchanged in the control group. Compared with the control group, losartan significantly decreased left ventricular mass index (LVMI), baPWV, and the plasma levels of brain natriuretic peptide and advanced glycation end products (AGE). Furthermore, multiple regression analysis showed significant correlations between changes in LVMI and changes in nighttime short-term BP variability, as well as between changes in LVMI and changes in the plasma levels of AGE. CONCLUSION These results suggest that losartan is beneficial for the suppression of pathological cardiovascular remodeling though its inhibitory effect on ambulatory short-term BP variability during nighttime.
Effect of losartan on ambulatory short-term blood pressure variability and cardiovascular remodeling in hypertensive patients on hemodialysis.
45449835
Myelin-directed autoimmunity is considered to play a key role in the pathogenesis of multiple sclerosis (MS). Increased production of both pro- and anti-inflammatory cytokines is a common finding in MS. Interleukin-17 (IL-17) is a recently described cytokine produced in humans almost exclusively by activated memory T cells, which can induce the production of proinflammatory cytokines and chemokines from parenchymal cells and macrophages. In situ hybridisation with synthetic oligonucleotide probes was adopted to detect and enumerate IL-17 mRNA expressing mononuclear cells (MNC) in blood and cerebrospinal fluid (CSF) from patients with MS and control individuals. Numbers of IL-17 mRNA expressing blood MNC were higher in patients with MS and acute aseptic meningoencephalitis (AM) compared to healthy individuals. Higher numbers of IL-17 mRNA expressing blood MNC were detected in MS patients examined during clinical exacerbation compared to remission. Patients with MS had higher numbers of IL-17 mRNA expressing MNC in CSF compared to blood. This increase in numbers of IL-17 mRNA expressing MNC in CSF was not observed in patients with AM. Our results thus demonstrate increased numbers of IL-17 mRNA expressing MNC in MS with higher numbers in CSF than blood, and with the highest numbers in blood during clinical exacerbations.
Interleukin-17 mRNA expression in blood and CSF mononuclear cells is augmented in multiple sclerosis.
45457778
The change in the world's age demographics and the predicted rise in the incidence of age-related diseases, including dementia, is a source of major public health concern. Major research effort in both the United States and Europe has been targeted toward understanding the pathogenesis and epidemiology of dementia. This article presents a general overview of the history of dementia research in Europe and how it compares with that in the United States. The review highlights the common issues which both U.S. and European researchers have identified and attempted to tackle. To maximize information gained from studies across the world, better harmonization of methodology is needed, as informed from current research practice.
A European perspective on population studies of dementia.
45461275
BACKGROUND PEPFAR, national governments, and other stakeholders are investing unprecedented resources to provide HIV treatment in developing countries. This study reports empirical data on costs and cost trends in a large sample of HIV treatment sites. DESIGN In 2006-2007, we conducted cost analyses at 43 PEPFAR-supported outpatient clinics providing free comprehensive HIV treatment in Botswana, Ethiopia, Nigeria, Uganda, and Vietnam. METHODS We collected data on HIV treatment costs over consecutive 6-month periods starting from scale-up of dedicated HIV treatment services at each site. The study included all patients receiving HIV treatment and care at study sites [62,512 antiretroviral therapy (ART) and 44,394 pre-ART patients]. Outcomes were costs per patient and total program costs, subdivided by major cost categories. RESULTS Median annual economic costs were US$ 202 (2009 USD) for pre-ART patients and US$ 880 for ART patients. Excluding antiretrovirals, per patient ART costs were US$ 298. Care for newly initiated ART patients cost 15-20% more than for established patients. Per patient costs dropped rapidly as sites matured, with per patient ART costs dropping 46.8% between first and second 6-month periods after the beginning of scale-up, and an additional 29.5% the following year. PEPFAR provided 79.4% of funding for service delivery, and national governments provided 15.2%. CONCLUSION Treatment costs vary widely between sites, and high early costs drop rapidly as sites mature. Treatment costs vary between countries and respond to changes in antiretroviral regimen costs and the package of services. Whereas cost reductions may allow near-term program growth, programs need to weigh the trade-off between improving services for current patients and expanding coverage to new patients.
The cost of providing comprehensive HIV treatment in PEPFAR-supported programs.
45487164
Caenorhabditis elegans oocytes, like those of most animals, arrest during meiotic prophase. Sperm promote the resumption of meiosis (maturation) and contraction of smooth muscle-like gonadal sheath cells, which are required for ovulation. We show that the major sperm cytoskeletal protein (MSP) is a bipartite signal for oocyte maturation and sheath contraction. MSP also functions in sperm locomotion, playing a role analogous to actin. Thus, during evolution, MSP has acquired extracellular signaling and intracellular cytoskeletal functions for reproduction. Proteins with MSP-like domains are found in plants, fungi, and other animals, suggesting that related signaling functions may exist in other phyla.
A sperm cytoskeletal protein that signals oocyte meiotic maturation and ovulation.
45548062
OBJECTIVE Policy discussions regarding the mental health needs of children and adolescents emphasize a lack of use of mental health services among youth, but few national estimates are available. The authors use three national data sets and examine ethnic disparities in unmet need (defined as having a need for mental health evaluation but not using any services in a 1-year period) to provide such estimates. METHOD The authors conducted secondary data analyses in three nationally representative household surveys fielded in 1996-1998: the National Health Interview Survey, the National Survey of American Families, and the Community Tracking Survey. They determined rates of mental health service use by children and adolescents 3-17 years of age and differences by ethnicity and insurance status. Among the children defined as in need of mental health services, defined by an estimator of mental health problems (selected items from the Child Behavior Checklist), they examined the association of unmet need with ethnicity and insurance status. RESULTS In a 12-month period, 2%-3% of children 3-5 years old and 6%-9% of children and adolescents 6-17 years old used mental health services. Of children and adolescents 6-17 years old who were defined as needing mental health services, nearly 80% did not receive mental health care. Controlling for other factors, the authors determined that the rate of unmet need was greater among Latino than white children and among uninsured than publicly insured children. CONCLUSIONS These findings reveal that most children who need a mental health evaluation do not receive services and that Latinos and the uninsured have especially high rates of unmet need relative to other children. Rates of use of mental health services are extremely low among preschool children. Research clarifying the reasons for high rates of unmet need in specific groups can help inform policy and clinical programs.
Unmet need for mental health care among U.S. children: variation by ethnicity and insurance status.
45581752
OBJECTIVE This article reviews psychology and behavioral economic approaches to HIV prevention, and examines the integration and application of these approaches in conditional economic incentive (CEI) programs for reducing HIV risk behavior. METHODS We discuss the history of HIV prevention approaches, highlighting the important insights and limitations of psychological theories. We provide an overview of the theoretical tenets of behavioral economics that are relevant to HIV prevention, and utilize CEIs as an illustrative example of how traditional psychological theories and behavioral economics can be combined into new approaches for HIV prevention. RESULTS Behavioral economic interventions can complement psychological frameworks for reducing HIV risk by introducing unique theoretical understandings about the conditions under which risky decisions are amenable to intervention. Findings from illustrative CEI programs show mixed but generally promising effects of economic interventions on HIV and sexually transmitted infection (STI) prevalence, HIV testing, HIV medication adherence, and drug use. CONCLUSIONS CEI programs can complement psychological interventions for HIV prevention and behavioral risk reduction. To maximize program effectiveness, CEI programs must be designed according to contextual and population-specific factors that may determine intervention applicability and success.
Conditional economic incentives for reducing HIV risk behaviors: integration of psychology and behavioral economics.
45638119
Application of stem cell biology to breast cancer research has been limited by the lack of simple methods for identification and isolation of normal and malignant stem cells. Utilizing in vitro and in vivo experimental systems, we show that normal and cancer human mammary epithelial cells with increased aldehyde dehydrogenase activity (ALDH) have stem/progenitor properties. These cells contain the subpopulation of normal breast epithelium with the broadest lineage differentiation potential and greatest growth capacity in a xenotransplant model. In breast carcinomas, high ALDH activity identifies the tumorigenic cell fraction, capable of self-renewal and of generating tumors that recapitulate the heterogeneity of the parental tumor. In a series of 577 breast carcinomas, expression of ALDH1 detected by immunostaining correlated with poor prognosis. These findings offer an important new tool for the study of normal and malignant breast stem cells and facilitate the clinical application of stem cell concepts.
ALDH1 is a marker of normal and malignant human mammary stem cells and a predictor of poor clinical outcome.
45651303
Concentrations of interleukin (IL)-6 and IL-8 in serum and synovial fluid obtained from patients with osteoarthritis (OA) of the knee were determined by the chemiluminescence-ELISA (CL-ELISA) method, the sensitivity of which is 100-1,000 times greater than that of the conventional ELISA method. The results were compared with those obtained from patients with rheumatoid arthritis (RA) and from healthy subjects. The mean IL-6 and IL-8 levels in synovial fluid indicated higher concentrations in RA than in OA. The IL-6 and IL-8 levels in serum were significantly higher in RA and OA relative to controls. Among OA patients in whom remarkable improvement was noted in hydrarthrosis, the synovial fluid IL-6 and IL-8 levels at the initial examination were relatively higher, and were markedly decreased after treatment with sodium hyaluronate (NaHA). Among those in whom no improvement was noted in hydrarthrosis, the synovial fluid IL-6 and IL-8 levels at the time of initial examination were relatively lower, and hydrarthrosis was not significantly improved even after treatment with NaHA. In addition, there was a tendency for the synovial fluid IL-6 and IL-8 levels to decrease as HA levels increased. Evaluation of X-ray findings revealed that the IL-6 levels in synovial fluid at the initial examination in low-grade cases tended to be significantly higher than in high-grade cases. In low-grade cases, as determined by X-ray findings, there was a significant decrease in IL-6 levels in synovial fluid after treatment with NaHA.
Interleukin-6 and interleukin-8 levels in serum and synovial fluid of patients with osteoarthritis.
45764440
The nonreceptor protein tyrosine kinase Src is overexpressed in 70% of pancreatic adenocarcinomas. Here, we describe the effect of molecular and pharmacological down-regulation of Src on incidence, growth, and metastasis of pancreatic tumor cells in an orthotopic model. Src expression in L3.6pl human pancreatic tumor cells was reduced by stable expression of a plasmid encoding small interfering RNA (siRNA) to c-src. In stable siRNA clones, Src expression was reduced >80%, with no change in expression of the related kinases c-Yes and c-Lyn, and proliferation rates were similar in all clones. Phosphorylation of Akt and p44/42 Erk mitogen-activated protein kinase and production of VEGF and IL-8 in culture supernatants were also reduced (P < 0.005). On orthotopic implantation of varying cell numbers into nude mice, tumor incidence was unchanged; however, in the siRNA clones, large tumors failed to develop, and incidence of metastasis was significantly reduced, suggesting that c-Src activity is critical to tumor progression. To examine this possibility further, animals bearing established wild-type tumors were treated with the Src/Abl-selective inhibitor BMS-354825 (dasatinib). Tumor size was decreased, and incidence of metastases was significantly reduced in treated mice compared with controls. These results demonstrate that Src activation contributes to pancreatic tumor progression in this model, offering Src as a candidate for targeted therapy.
Inhibition of SRC expression and activity inhibits tumor progression and metastasis of human pancreatic adenocarcinoma cells in an orthotopic nude mouse model.
45770026
Eicosapentaenoic acid (EPA) has beneficial effects in many inflammatory disorders. In this study, dietary EPA was converted to 17,18-epoxyeicosatetraenoic acid (17,18-EpETE) by ω-3 epoxygenation in the mouse peritoneal cavity. Mediator lipidomics revealed a series of novel oxygenated metabolites of 17,18-EpETE, and one of the major metabolites, 12-hydroxy-17,18-epoxyeicosatetraenoic acid (12-OH-17,18-EpETE), displayed a potent anti-inflammatory action by limiting neutrophil infiltration in murine zymosan-induced peritonitis. 12-OH-17,18-EpETE inhibited leukotriene B4-induced neutrophil chemotaxis and polarization in vitro in a low nanomolar range (EC50 0.6 nM). The complete structures of two natural isomers were assigned as 12S-OH-17R,18S-EpETE and 12S-OH-17S,18R-EpETE, using chemically synthesized stereoisomers. These natural isomers displayed potent anti-inflammatory action, whereas the unnatural stereoisomers were essentially devoid of activity. These results demonstrate that 17,18-EpETE derived from dietary EPA is converted to a potent bioactive metabolite 12-OH-17,18-EpETE, which may generate an endogenous anti-inflammatory metabolic pathway.
Eicosapentaenoic acid is converted via ω-3 epoxygenation to the anti-inflammatory metabolite 12-hydroxy-17,18-epoxyeicosatetraenoic acid.
45820464
Five strains of scrapie agent were used as intracerebral inocula for 2 inbred mouse strains, C57BL and VM, and their F1 cross. The degree of vacuolation in specified regions of the brain, and the relative distribution of this damage in 9 regions represented as a “lesion profile”, was different for each agent. Any of the 5 scrapie agents could be distinguished from the others with a very high degree of reliability solely on the basis of these histological parameters, using either strain of mouse. The lesion profile was unaffected by the dose of the agent, using doses of ME7 agent ranging over 6 orders of magnitude in C57BL mice. The genotype of mouse had a marked effect on the overall degree of vacuolation and on the shape of the lesion profile: these effects were more profound with some agents than others. In certain areas of the brain, depending upon the strain of agent used, the (C57BL × VM)F1 cross was found to have either significantly more or significantly less vacuolation than either parental genotype. The genetic control of the lesion profile was found to be too complex for more detailed analysis in these data.
Scrapie in mice. Agent-strain differences in the distribution and intensity of grey matter vacuolation.
45875990
Cyclin A2 activates the cyclin-dependent kinases Cdk1 and Cdk2 and is expressed at elevated levels from S phase until early mitosis. We found that mutant mice that cannot elevate cyclin A2 are chromosomally unstable and tumor-prone. Underlying the chromosomal instability is a failure to up-regulate the meiotic recombination 11 (Mre11) nuclease in S phase, which leads to impaired resolution of stalled replication forks, insufficient repair of double-stranded DNA breaks, and improper segregation of sister chromosomes. Unexpectedly, cyclin A2 controlled Mre11 abundance through a C-terminal RNA binding domain that selectively and directly binds Mre11 transcripts to mediate polysome loading and translation. These data reveal cyclin A2 as a mechanistically diverse regulator of DNA replication combining multifaceted kinase-dependent functions with a kinase-independent, RNA binding–dependent role that ensures adequate repair of common replication errors.
Cyclin A2 is an RNA binding protein that controls Mre11 mRNA translation
45908102
The Expanded Program on Immunization (EPI) is using a simplified cluster sampling method, based on the random selection of 210 children in 30 clusters of 7 children each, to estimate immunization coverage levels. This article analyzes the results of this method in actual and computer simulated surveys. Results from 60 actual surveys conducted in 25 countries were available for analysis, for a total of 446 sample estimations of immunization coverage. 83% of the sample results had 95% confidence limits within + or - 10%, and none of the surveys had 95% confidence limits exceeding + or - 13%. In addition, 12 hypothetical population strata with immunization coverage rates ranging from 10%-99% were established for the purposes of computer simulation, and 10 hypothetical communities were established by allocating to them various proportions of each of the strata. These simulated surveys also supported the validity of the EPI method: over 95% of the results were less than + or - 10% from the actual population mean. The precision of this method, as estimated from the results of both actual and simulated surveys, is considered satisfactory for the requirements of the EPI. Among the actual surveys, the proportion of results whose confidence limits exceeded + or - 10% was greatest (50%) when immunization coverage in the sample was 45%-54%.
Cluster sampling to assess immunization coverage: a review of experience with a simplified sampling method.
45920278
BACKGROUND Studies have shown that women use more health care services than men. We used important independent variables, such as patient sociodemographics and health status, to investigate gender differences in the use and costs of these services. METHODS New adult patients (N = 509) were randomly assigned to primary care physicians at a university medical center. Their use of health care services and associated charges were monitored for 1 year of care. Self-reported health status was measured using the Medical Outcomes Study Short Form-36 (SF-36). We controlled for health status, sociodemographic information, and primary care physician specialty in the statistical analyses. RESULTS Women had significantly lower self-reported health status and lower mean education and income than men. Women had a significantly higher mean number of visits to their primary care clinic and diagnostic services than men. Mean charges for primary care, specialty care, emergency treatment, diagnostic services, and annual total charges were all significantly higher for women than men; however, there were no differences for mean hospitalizations or hospital charges. After controlling for health status, sociodemographics, and clinic assignment, women still had higher medical charges for all categories of charges except hospitalizations. CONCLUSIONS Women have higher medical care service utilization and higher associated charges than men. Although the appropriateness of these differences was not determined, these findings have implications for health care.
Gender differences in the utilization of health care services.
46112052
Recombinant human tumor necrosis factor (rH-TNF) is a cytokine with direct antitumor properties. In a phase I trial we continuously infused rH-TNF for 24 hours. We gave a total of 115 courses of therapy to 50 patients. Doses ranged from 4.5 to 645 micrograms of rH-TNF/m2. Systemic toxicity, including fever, chills, fatigue, and hypotension, increased with the dose of rH-TNF administered. Doses greater than 454 micrograms/m2 frequently caused severe lethargy and fatigue, which precluded hospital discharge of the patient at the completion of therapy. The dose-limiting toxicity was hypotension, and five patients treated at the two highest dose levels required dopamine treatment. Other organ-specific toxicity was modest and spontaneously resolved after 48 hours. The 24-hour infusions of rH-TNF were associated with significant decreases in serum cholesterol and high-density lipoprotein levels. Pharmacokinetic studies using an enzyme-linked immunosorbent assay demonstrated peak plasma rH-TNF levels of 90-900 pg/mL. Despite continuous infusion of rH-TNF, no steady-state level was achieved. The recommended phase II dose for rH-TNF as a 24-hour continuous infusion is 545 micrograms/m2.
Recombinant human tumor necrosis factor administered as a 24-hour intravenous infusion. A phase I and pharmacologic study.
46127781
Cells or cell-free fluid of malignant pleural effusion could be important clinical specimen for epidermal growth factor receptor (EGFR) mutation screening in advanced non-small cell lung cancer (NSCLC) patients. However, their usefulness in mutation detection has not been well compared. In this study we recruited 26 East Asian NSCLC patients with malignant pleural effusion, determined the mutation status of EGFR in both cells and matched cell-free fluid with the use of sequencing and mutant-enriched PCR. After comparing the mutation spectrums, we found both the cells and cell-free pleural fluid may be feasible clinical specimen for EGFR mutation detection in unresectable NSCLC given sensitive genotyping assays employed. Direct sequencing could miss a significant portion of mutations in these heterogeneous specimens. More sensitive methods, such as mutant-enriched PCR and gene scan, could provide more reliable mutational information.
Detection and comparison of epidermal growth factor receptor mutations in cells and fluid of malignant pleural effusion in non-small cell lung cancer.
46135768
Endosomal Toll-like receptors (TLRs) 7 and 9 recognize viral pathogens and induce signals leading to the activation of nuclear factor κB (NF-κB)-dependent proinflammatory cytokines and interferon regulatory factor 7 (IRF7)-dependent type I interferons (IFNs). Recognition of viral nucleic acids by TLR9 requires its cleavage in the endolysosomal compartment. Here, we show that TLR9 signals leading to the activation of type I IFN, but not proinflammatory cytokine genes, require TLR9 trafficking from endosomes to a specialized lysosome-related organelle. Furthermore, we identify adapter protein-3 as the protein complex responsible for the trafficking of TLR9 to this subcellular compartment. Our results reveal an intracellular mechanism for bifurcation of TLR9 signals by selective receptor trafficking within the endosomal system.
Materials and Methods Figs. S1 to S15 References Supporting Online Materials
46153874
Sedimentation analysis in the analytical ultracentrifuge can be employed to detect macromolecular interactions. Whenever two molecules interact the mass of the resulting complex is increased and this is reflected in the sedimentation behavior. In this chapter we discuss how this phenomenon can be utilized to determine quantitative parameters of an interaction. An example, interaction of single-stranded DNA binding protein with a subunit of DNA polymerase III holoenzyme is given together with a thorough treatment of the relating theory and a description of evaluation algorithms.
Sedimentation velocity method in the analytical ultracentrifuge for the study of protein-protein interactions.
46182525
Hip scans of U.S. adults aged 20-99 years acquired in the Third National Health and Nutrition Examination Survey (NHANES III) using dual-energy X-ray absorptiometry (DXA) were analyzed with a structural analysis program. The program analyzes narrow (3 mm wide) regions at specific locations across the proximal femur to measure bone mineral density (BMD) as well as cross-sectional areas (CSAs), cross-sectional moments of inertia (CSMI), section moduli, subperiosteal widths, and estimated mean cortical thickness. Measurements are reported here on a non-Hispanic white subgroup of 2,719 men and 2,904 women for a cortical region across the proximal shaft 2 cm distal to the lesser trochanter and a mixed cortical/trabecular region across the narrowest point of the femoral neck. Apparent age trends in BMD and section modulus were studied for both regions by sex after correction for body weight. The BMD decline with age in the narrow neck was similar to that seen in the Hologic neck region; BMD in the shaft also declined, although at a slower rate. A different pattern was seen for section modulus; furthermore, this pattern depended on sex. Specifically, the section modulus at both the narrow neck and the shaft regions remains nearly constant until the fifth decade in females and then declined at a slower rate than BMD. In males, the narrow neck section modulus declined modestly until the fifth decade and then remained nearly constant whereas the shaft section modulus was static until the fifth decade and then increased steadily. The apparent mechanism for the discord between BMD and section modulus is a linear expansion in subperiosteal diameter in both sexes and in both regions, which tends to mechanically offset net loss of medullary bone mass. These results suggest that aging loss of bone mass in the hip does not necessarily mean reduced mechanical strength. Femoral neck section moduli in the elderly are on the average within 14% of young values in females and within 6% in males.
Structural trends in the aging femoral neck and proximal shaft: analysis of the Third National Health and Nutrition Examination Survey dual-energy X-ray absorptiometry data.
46193388
Bone marrow stem cells give rise to a variety of hematopoietic lineages and repopulate the blood throughout adult life. We show that, in a strain of mice incapable of developing cells of the myeloid and lymphoid lineages, transplanted adult bone marrow cells migrated into the brain and differentiated into cells that expressed neuron-specific antigens. These findings raise the possibility that bone marrow-derived cells may provide an alternative source of neurons in patients with neurodegenerative diseases or central nervous system injury.
Turning blood into brain: cells bearing neuronal antigens generated in vivo from bone marrow.
46193478
Abstract A simple technique has been developed for the study of the external form and structure of virus particles. High contrast with good preservation is obtained by mixing virus preparations with 1% phosphotungstic acid adjusted to pH 7.5 and spraying directly onto electron microscope supporting films made from evaporated carbon. The application of the technique to tobacco mosaic virus and turnip yellow mosaic virus is described. Structural details suggested by X-ray diffraction methods have been resolved.
A negative staining method for high resolution electron microscopy of viruses.
46202852
Several recent reports indicate that cholesterol might play an important role in human immunodeficiency virus type 1 (HIV-1) replication. We investigated the effects of HIV-1 infection on cholesterol biosynthesis and uptake using microarrays. HIV-1 increased gene expression of cholesterol genes in both transformed T-cell lines and primary CD4(+) T cells. Consistent with our microarray data, (14)C-labeled mevalonate and acetate incorporation was increased in HIV-1-infected cells. Our data also demonstrate that changes in cholesterol biosynthesis and uptake are only observed in the presence of functional Nef, suggesting that increased cholesterol synthesis may contribute to Nef-mediated enhancement of virion infectivity and viral replication.
Nef induces multiple genes involved in cholesterol synthesis and uptake in human immunodeficiency virus type 1-infected T cells.
46248894
Long intergenic noncoding RNAs (lincRNAs) regulate chromatin states and epigenetic inheritance. Here, we show that the lincRNA HOTAIR serves as a scaffold for at least two distinct histone modification complexes. A 5' domain of HOTAIR binds polycomb repressive complex 2 (PRC2), whereas a 3' domain of HOTAIR binds the LSD1/CoREST/REST complex. The ability to tether two distinct complexes enables RNA-mediated assembly of PRC2 and LSD1 and coordinates targeting of PRC2 and LSD1 to chromatin for coupled histone H3 lysine 27 methylation and lysine 4 demethylation. Our results suggest that lincRNAs may serve as scaffolds by providing binding surfaces to assemble select histone modification enzymes, thereby specifying the pattern of histone modifications on target genes.
Long noncoding RNA as modular scaffold of histone modification complexes
46266579
BACKGROUND The amyloid fibril deposits that cause systemic amyloidosis always contain the nonfibrillar normal plasma protein, serum amyloid P component (SAP). The drug (R)-1-[6-[(R)-2-carboxy-pyrrolidin-1-yl]-6-oxo-hexanoyl]pyrrolidine-2-carboxylic acid (CPHPC) efficiently depletes SAP from the plasma but leaves some SAP in amyloid deposits that can be specifically targeted by therapeutic IgG anti-SAP antibodies. In murine amyloid A type amyloidosis, the binding of these antibodies to the residual SAP in amyloid deposits activates complement and triggers the rapid clearance of amyloid by macrophage-derived multinucleated giant cells. METHODS We conducted an open-label, single-dose-escalation, phase 1 trial involving 15 patients with systemic amyloidosis. After first using CPHPC to deplete circulating SAP, we infused a fully humanized monoclonal IgG1 anti-SAP antibody. Patients with clinical evidence of cardiac involvement were not included for safety reasons. Organ function, inflammatory markers, and amyloid load were monitored. RESULTS There were no serious adverse events. Infusion reactions occurred in some of the initial recipients of larger doses of antibody; reactions were reduced by slowing the infusion rate for later patients. At 6 weeks, patients who had received a sufficient dose of antibody in relation to their amyloid load had decreased liver stiffness, as measured with the use of transient elastography. These patients also had improvements in liver function in association with a substantial reduction in hepatic amyloid load, as shown by means of SAP scintigraphy and measurement of extracellular volume by magnetic resonance imaging. A reduction in kidney amyloid load and shrinkage of an amyloid-laden lymph node were also observed. CONCLUSIONS Treatment with CPHPC followed by an anti-SAP antibody safely triggered clearance of amyloid deposits from the liver and some other tissues. (Funded by GlaxoSmithKline; ClinicalTrials.gov number, NCT01777243.).
Therapeutic Clearance of Amyloid by Antibodies to Serum Amyloid P Component.
46277811
Background: The relationship of LPA single nucleotide polymorphisms (SNPs), apolipoprotein(a) isoforms, and lipoprotein(a) [Lp(a)] levels with major adverse cardiovascular events (MACE) in different ethnic groups is not well known. Methods: LPA SNPs, apolipoprotein(a) isoforms, Lp(a), and oxidized phospholipids on apolipoprotein B-100 (OxPL-apoB) levels were measured in 1792 black, 1030 white, and 597 Hispanic subjects enrolled in the Dallas Heart Study. Their interdependent relationships and prospective association with MACE after median 9.5-year follow-up were determined. Results: LPA SNP rs3798220 was most prevalent in Hispanics (42.38%), rs10455872 in whites (14.27%), and rs9457951 in blacks (32.92%). The correlation of each of these SNPs with the major apolipoprotein(a) isoform size was highly variable and in different directions among ethnic groups. In the entire cohort, Cox regression analysis with multivariable adjustment revealed that quartiles 4 of Lp(a) and OxPL-apoB were associated with hazard ratios (95% confidence interval) for time to MACE of 2.35 (1.50–3.69, P<0.001) and 1.89 (1.26–2.84, P=0.003), respectively, versus quartile 1. Addition of the major apolipoprotein(a) isoform and the 3 LPA SNPs to these models attenuated the risk, but significance was maintained for both Lp(a) and OxPL-apoB. Evaluating time to MACE in specific ethnic groups, Lp(a) was a positive predictor and the size of the major apolipoprotein(a) isoform was an inverse predictor in blacks, the size of the major apolipoprotein(a) isoform was an inverse predictor in whites, and OxPL-apoB was a positive predictor in Hispanics. Conclusions: The prevalence and association of LPA SNPs with size of apolipoprotein(a) isoforms, Lp(a), and OxPL-apoB levels are highly variable and ethnicity-specific. The relationship to MACE is best explained by elevated plasma Lp(a) or OxPL-apoB levels, despite significant ethnic differences in LPA genetic markers.
LPA Gene, Ethnicity, and Cardiovascular Events
46305977
The maize abscisic acid responsive protein Rab17 is a highly phosphorylated late embryogenesis abundant protein involved in plant responses to stress. In this study, we provide evidence of the importance of Rab17 phosphorylation by protein kinase CK2 in growth-related processes under stress conditions. We show the specific interaction of Rab17 with the CK2 regulatory subunits CK2 beta-1 and CK2 beta-3, and that these interactions do not depend on the phosphorylation state of Rab17. Live-cell fluorescence imaging of both CK2 and Rab17 indicates that the intracellular dynamics of Rab17 are regulated by CK2 phosphorylation. We found both CK2 beta subunits and Rab17 distributed over the cytoplasm and nucleus. By contrast, catalytic CK2 alpha subunits and a Rab17 mutant protein (mRab17) that is not a substrate for CK2 phosphorylation remain accumulated in the nucleoli. A dual-color image shows that the CK2 holoenzyme accumulates mainly in the nucleus. The importance of Rab17 phosphorylation in vivo was assessed in transgenic plants. The overexpression of Rab17, but not mRab17, arrests the process of seed germination under osmotic stress conditions. Thus, the role of Rab17 in growth processes is mediated through its phosphorylation by protein kinase CK2.
Protein kinase CK2 modulates developmental functions of the abscisic acid responsive protein Rab17 from maize.
46328296
Patients with essential hypertension exhibit blunted endothelium-dependent vasodilator responses, which may be largely attributable to reduced bioactivity of nitric oxide (NO). Therefore, we measured the end product of NO, nitrate plus nitrite (nitrogen oxide), and examined the relationship between the degree of hypertension and plasma nitrate plus nitrite levels in patients with essential hypertension. The combined plasma concentration of nitrate plus nitrite, end products of NO metabolism, was reduced in individuals with essential hypertension relative to that in control subjects (15.7+/-1.1 versus 22.8+/-1.4 mmol x L(-1), P<.001); individuals with borderline hypertension showed values that were intermediate between those of the other two groups (18.2+/-1.2 mmol x L(-1), P<.001). The plasma nitrogen oxide concentration showed significant inverse correlations with both systolic and diastolic blood pressures. The basal concentration of nitrogen oxide in the plasma was reduced, at least in the peripheral circulation, in individuals with essential hypertension.
Reduced plasma concentrations of nitrogen oxide in individuals with essential hypertension.
46346525
Mu transposons carrying the chloramphenicol resistance marker have been inserted into the cloned Escherichia coli genes sodA and sodB coding for manganese superoxide dismutase (MnSOD) and iron superoxide dismutase (FeSOD) respectively, creating mutations and gene fusions. The mutated sodA or sodB genes were introduced into the bacterial chromosome by allelic exchange. The resulting mutants were shown to lack the corresponding SOD by activity measurements and immunoblot analysis. Aerobically, in rich medium, the absence of FeSOD or MnSOD had no major effect on growth or sensitivity to the superoxide generator, paraquat. In minimal medium aerobic growth was not affected, but the sensitivity to paraquat was increased, especially in the sodA mutant. A sodA sodB double mutant completely devoid of SOD was also obtained. It was able to grow aerobically in rich medium, its catalase level was unaffected and it was highly sensitive to paraquat and hydrogen peroxide; the double mutant was unable to grow aerobically on minimal glucose medium. Growth could be restored by removing oxygen, by providing an SOD-overproducing plasmid or by supplementing the medium with the 20 amino acids. It is concluded that the total absence of SOD in E. coli creates a conditional sensitivity to oxygen.
Isolation of superoxide dismutase mutants in Escherichia coli: is superoxide dismutase necessary for aerobic life?
46353045
Late presentation remains a major concern despite the dramatically improved prognosis realized by ART. We define a first presentation for HIV care during the course of HIV infection as 'late' if an AIDS-defining opportunistic disease is apparent, or if CD4+ T-cells are <200/microl. In the Western world, approximately 10 and 30% of HIV-infected individuals still present with CD4+ T-cells <50 and <200/microl, respectively; estimates are substantially higher for developing countries. Diagnosis and treatment of opportunistic diseases and intense supportive in-hospital care take precedence over ART. Benefits of starting ART without delay, that is, when opportunistic diseases are still active, include faster resolution of opportunistic diseases and a decreased risk of recurrence. The downside of starting ART without delay could include toxicity, drug interactions and immune reconstitution inflammatory syndrome (IRIS). Among asymptomatic or oligosymptomatic individuals presenting late, where ART and primary prophylaxis are initiated, approximately 10-20% will become symptomatic from drug toxicity or undiagnosed opportunistic complications, including IRIS, which require appropriate therapies. In this review we describe late presentation to HIV care, the scale of the problem, the evaluation of a late-presenting patient and challenges associated with initiation of potent antiretroviral therapy (ART) in the setting of acute opportunistic infections and other comorbidities.
Late presentation of HIV-infected individuals.
46355579
Health professionals and the public need to understand the natural history of human papillomavirus (HPV) infections of the cervix to best use the information provided by new molecular screening tests. We investigated outcomes of 800 carcinogenic HPV infections detected in 599 women at enrollment into a population-based cohort (Guanacaste, Costa Rica). For individual infections, we calculated cumulative proportions of three outcomes (viral clearance, persistence without cervical intraepithelial neoplasia grade 2 or worse [CIN2+], or persistence with new diagnosis of CIN2+) at successive 6-month time points for the first 30 months of follow-up. Cervical specimens were tested for carcinogenic HPV genotypes using an L1 degenerate-primer polymerase chain reaction method. Infections typically cleared rapidly, with 67% (95% confidence interval [CI] = 63% to 70%) clearing by 12 months. However, among infections that persisted at least 12 months, the risk of CIN2+ diagnosis by 30 months was 21% (95% CI = 15% to 28%). The risk of CIN2+ diagnosis was highest among women younger than 30 years with HPV-16 infections that persisted for at least 12 months (53%; 95% CI = 29% to 76%). These findings suggest that the medical community should emphasize persistence of cervical HPV infection, not single-time detection of HPV, in management strategies and health messages.
Rapid clearance of human papillomavirus and implications for clinical focus on persistent infections.
46437558
AIMS Alcohol is believed to be an important factor behind the sharp rise in mortality during the period 1990-94 in Russia. However, the rise in the standard alcohol consumption proxy does not seem to be sufficient to explain all the increase in mortality. This study adopts a novel approach to exploring the role of the alcohol factor in the increased mortality by investigating whether the mismatch between trends in mortality and recorded alcohol consumption is due to an underestimation of the consumption increase. DESIGN AND MEASUREMENTS First, the alcohol effect on the male accident rate was estimated using data for the period 1959-89. Next, the estimated alcohol effect and the observed accident mortality rate for the period 1990-98 were used to backcast alcohol consumption during that period. Thirdly, the backcasted alcohol series was used to predict trajectories in alcohol poisoning mortality, the homicide rate and all-cause mortality during the period 1990-98. FINDINGS There was a markedly stronger increase in the backcasted consumption proxy than in the standard alcohol consumption proxy during the period 1990-98. There was a substantial gap between the observed mortality rates and the rates predicted from the standard alcohol consumption proxy, whereas the predictions from the backcasted alcohol proxy were much closer to the target. CONCLUSIONS Much of the rise in Russian mortality in 1990-94 appears to have been due to the increase in population drinking, but this increase is grossly underestimated by the commonly used consumption proxy combining alcohol sales, estimation of illicit alcohol production and proportion of alcohol-positive violent deaths.
The role of alcohol in the Russian mortality crisis.
46451940
Lateral hypothalamic (LH) injections of the excitatory neurotransmitter glutamate, or its excitatory amino acid (EAA) agonists, kainic acid (KA), D,L-alpha-amino-3-hydroxy-5-methyl-isoxazole propionic acid (AMPA), or N-methyl-D-aspartic acid (NMDA), can rapidly elicit an intense feeding response in satiated rats. To determine whether the LH is the actual locus of this effect, we compared these compounds' ability to stimulate feeding when injected into the LH, versus when injected into sites bracketing this region. Food intake in groups of adult male rats was measured 1 h after injection of glutamate (30-900 nmol), KA (0.1-1.0 nmol), AMPA (0.33-3.3 nmol), NMDA (0.33-33.3 nmol) or vehicle, through chronically implanted guide cannulas, into one of seven brain sites. These sites were: the LH, the anterior and posterior tips of the LH, the thalamus immediately dorsal to the LH, the amygdala just lateral to the LH, or the paraventricular and perifornical areas medial to the LH. The results show that across doses and agonists the eating-stimulatory effects were largest with injections into the LH. In the LH, glutamate between 300 and 900 nmol elicited a dose-dependent eating response of up to 5 g within 1 h (P < 0.01). Each of the other agonists at doses of 3.3 nmol or less elicited eating responses of at least 10 g with injections into this site. Injections into the other brain sites produced either no eating, or occasionally smaller and less consistent eating responses.(ABSTRACT TRUNCATED AT 250 WORDS)
The lateral hypothalamus: a primary site mediating excitatory amino acid-elicited eating.
46478393
RNA interference is the most rapid method for generation of conditional knockdown mutants in Trypanosoma brucei. The dual T7 promoter (pZJM) and the stem-loop vectors have been widely used to generate stable inducible RNAi cell lines with the latter providing tighter regulatory control. However, the steps for cloning stem-loop constructs are cumbersome requiring either multiple cloning steps or multi-fragment ligation reactions. We report the development of a vector (pTrypRNAiGate) derived from pLEW100 that utilizes the Gateway® recombination system to facilitate easy production of hairpin RNA constructs. This approach allows the final stem-loop RNAi construct to be generated from a single cloning step of the PCR-derived gene fragment followed by an in vitro recombination reaction. The new vector facilitates high-throughput applications for gene silencing and provides a tool for functional genomics in T. brucei.
A Gateway® compatible vector for gene silencing in bloodstream form Trypanosoma brucei.
46485368
BACKGROUND Calcium supplementation has been shown to decrease the risk of recurrence of colorectal adenomas in randomized trials. However, the duration of this protective effect after cessation of active supplementation is not known. METHODS In the Calcium Polyp Prevention Study, 930 subjects with a previous colorectal adenoma were randomly assigned from November 1988 through April 1992 to receive placebo or 1200 mg of elemental calcium daily for 4 years. The Calcium Follow-up Study was an observational phase of the trial that tracked adenoma occurrence for an average of 7 years after the end of randomized treatment and gathered information regarding the use of medications, vitamins, and supplements during that time. We obtained follow-up information for 822 subjects, 597 of whom underwent at least one colonoscopy after the end of study treatment and are included in this analysis. Generalized linear models were used to compute relative risks (RRs) and 95% confidence intervals (CIs) for the effect of randomized calcium treatment on risk of adenoma recurrence during the first 5 years after study treatment ended and during the subsequent 5 years. Statistical tests were two-sided. RESULTS During the first 5 years after randomized treatment ended, subjects in the calcium group still had a substantially and statistically significantly lower risk of any adenoma than those in the placebo group (31.5% versus 43.2%; adjusted RR = 0.63, 95% CI = 0.46 to 0.87, P = .005) and a smaller and not statistically significant reduction in risk of advanced adenomas (adjusted RR = 0.85, 95% CI = 0.43 to 1.69, P = .65). However, the randomized treatment was not associated with the risk of any type of polyp during the next 5 years. The findings were broadly similar when the analysis was restricted to subjects who did not report use of any calcium supplements after the treatment phase of the trial ended. CONCLUSION The protective effect of calcium supplementation on risk of colorectal adenoma recurrence extends up to 5 years after cessation of active treatment, even in the absence of continued supplementation.
Prolonged effect of calcium supplementation on risk of colorectal adenomas in a randomized trial.
46517055
Uncontrolled proteolysis by neutrophil serine proteases (NSPs) in lung secretions is a hallmark of cystic fibrosis (CF). We have shown that the active neutrophil elastase, protease 3, and cathepsin G in CF sputum resist inhibition in part by exogenous protease inhibitors. This resistance may be due to their binding to neutrophil extracellular traps (NETs) secreted by the activated neutrophils in CF sputum and to genomic DNA released from senescent and dead neutrophils. Treating CF sputum with DNase dramatically increases its elastase activity, which can then be stoichiometrically inhibited by exogenous elastase inhibitors. However, DNase treatment does not increase the activities of protease 3 and cathepsin G, indicating their different distribution and/or binding in CF sputum. Purified blood neutrophils secrete NETs when stimulated by the opportunistic CF bacteria Pseudomonas aeruginosa and Staphylococcus aureus. The activities of the three proteases were unchanged in these conditions, but subsequent DNase treatment produced a dramatic increase in all three proteolytic activities. Neutrophils activated with a calcium ionophore did not secrete NETs but released huge amounts of active proteases whose activities were not modified by DNase. We conclude that NETs are reservoirs of active proteases that protect them from inhibition and maintain them in a rapidly mobilizable status. Combining the effects of protease inhibitors with that of DNA-degrading agents could counter the deleterious proteolytic effects of NSPs in CF lung secretions.
Influence of DNA on the activities and inhibition of neutrophil serine proteases in cystic fibrosis sputum.
46565020
BACKGROUND AN1792 (beta-amyloid [Abeta]1-42) immunization reduces Abeta plaque burden and preserves cognitive function in APP transgenic mice. The authors report the results of a phase IIa immunotherapy trial of AN1792(QS-21) in patients with mild to moderate Alzheimer disease (AD) that was interrupted because of meningoencephalitis in 6% of immunized patients. METHODS This randomized, multicenter, placebo-controlled, double-blind trial of IM AN1792 225 microg plus the adjuvant QS-21 50 microg (300 patients) and saline (72 patients) included patients aged 50 to 85 years with probable AD, Mini-Mental State Examination (MMSE) 15 to 26. Injections were planned for months 0, 1, 3, 6, 9, and 12. Safety and tolerability were evaluated, and pilot efficacy (AD Assessment Scale-Cognitive Subscale [ADAS-Cog], MRI, neuropsychological test battery [NTB], CSF tau, and Abeta42) was assessed in anti-AN1792 antibody responder patients (immunoglobulin G titer > or = 1:2,200). RESULTS Following reports of meningoencephalitis (overall 18/300 [6%]), immunization was stopped after one (2 patients), two (274 patients), or three (24 patients) injections. Of the 300 AN1792(QS-21)-treated patients, 59 (19.7%) developed the predetermined antibody response. Double-blind assessments were maintained for 12 months. No significant differences were found between antibody responder and placebo groups for ADAS-Cog, Disability Assessment for Dementia, Clinical Dementia Rating, MMSE, or Clinical Global Impression of Change, but analyses of the z-score composite across the NTB revealed differences favoring antibody responders (0.03 +/- 0.37 vs -0.20 +/- 0.45; p = 0.020). In the small subset of subjects who had CSF examinations, CSF tau was decreased in antibody responders (n = 11) vs placebo subjects (n = 10; p < 0.001). CONCLUSION Although interrupted, this trial provides an indication that Abeta immunotherapy may be useful in Alzheimer disease.
Clinical effects of Abeta immunization (AN1792) in patients with AD in an interrupted trial.
46565968
Quantitative assessment of metastatic disease in bone is often considered immeasurable and, as such, patients with skeletal metastases are often excluded from clinical trials. In order to effectively quantify the impact of metastatic tumor involvement in the spine, accurate segmentation of the vertebra is required. Manual segmentation can be accurate but involves extensive and time-consuming user interaction. Potential solutions to automating segmentation of metastatically involved vertebrae are demons deformable image registration and level set methods. The purpose of this study was to develop a semiautomated method to accurately segment tumor-bearing vertebrae using the aforementioned techniques. By maintaining morphology of an atlas, the demons-level set composite algorithm was able to accurately differentiate between trans-cortical tumors and surrounding soft tissue of identical intensity. The algorithm successfully segmented both the vertebral body and trabecular centrum of tumor-involved and healthy vertebrae. This work validates our approach as equivalent in accuracy to an experienced user.
Quantitative characterization of metastatic disease in the spine. Part I. Semiautomated segmentation using atlas-based deformable registration and the level set method.
46594244
In response to a variety of stimuli, dendritic cells (DCs) transform from immature cells specialized for antigen capture into mature cells specialized for T cell stimulation. During maturation, the DCs acquire an enhanced capacity to form and accumulate peptide-MHC (major histocompatibility complex) class II complexes. Here we show that a key mechanism responsible for this alteration was the generalized activation of lysosomal function. In immature DCs, internalized antigens were slowly degraded and inefficiently used for peptide loading. Maturation induced activation of the vacuolar proton pump that enhanced lysosomal acidification and antigen proteolysis, facilitating efficient formation of peptide-MHC class II complexes. Lysosomal function in DCs thus appears to be specialized for the developmentally regulated processing of internalized antigens.
Activation of lysosomal function during dendritic cell maturation.
46602807
The activities of cefotaxime (CTX) and desacetyl cefotaxime (des-CTX) were tested both singly and in combination against 173 anaerobic clinical isolates. The MIC of CTX for 50% of 60 Bacteroides fragilis isolates was 22.4 micrograms/ml in broth, compared with 47.4 micrograms/ml in agar. This reduced efficacy in agar was seen with all species tested and is in apparent conflict with reported clinical efficacy of the drug. Synergy between CTX and des-CTX was observed with 70 to 100% of the isolates, including 60% of all Bacteroides spp. tested. The susceptibility results in a synergy system correlated well with those noted in a broth-disk elution method incorporating 32 micrograms of CTX and 8 micrograms of des-CTX per ml. The correlation was poorer when the broth-disk method contained 16 micrograms of CTX and 8 micrograms of des-CTX per ml.
Comparison of agar dilution, microdilution, and disk elution methods for measuring the synergy of cefotaxime and its metabolite against anaerobes.