Small Intestinal Angioectasia: Characterization, Risk Factors, and Rebleeding.

BACKGROUND: Gastrointestinal angioectasias (AEs) represent the most common vascular malformation within the gastrointestinal tract. This study sought to characterize epidemiologic/comorbid risk factors for AEs, rebleeding, and patterns of anatomic distribution within the small intestine. STUDY: This retrospective observational cohort study included 158 patients with AEs on capsule endoscopy (CE) from 2007 to 2015. Epidemiologic/comorbid data were collected and incorporated into final analysis. Each AE was categorized by location using a small bowel transit time-based quartile system. Rebleeding was evaluated following CE. Multivariate logistic regression was applied to statistically significant factors on univariate analysis to determine independent risk factors for rebleeding. RESULTS: Most lesions were found in the first quartile (67.1%). Rebleeding occurred in 46 (29.7%) of the 156 patients for whom data were available. Rates of rebleeding were significantly higher among older patients (74.4 vs. 67.7 y, P=0.001), those with active bleeding on CE (41.3% vs. 16.5%, P=0.001), those with a history of aortic stenosis (21.7% vs. 9.2%, P=0.033), and those with AEs presents in quartile 3 (26.1% vs. 8.3%, P=0.003). Age, active bleeding on CE, and AE presence in quartile 3 were independently associated with rebleeding in multivariate analysis (P=0.009, 0.023, and 0.008, respectively). CONCLUSIONS: These data help improve our knowledge of AEs regarding risk factors for rebleeding, and utilizes a novel small bowel transit time-based quartile localization method that may simplify future research and comparisons of anatomic distribution and behavior of small bowel AEs.

A model of fracture risk used to examine the link between bone mineral density and the impact of different therapeutic mechanisms on fracture outcomes in patients with osteoporosis.

A hazard model of fracture was developed using individual patient data (IPD) from the NHANES (2005-2008) database and summary-level data from an aggregate dataset (AD). The AD was built by performing a comprehensive and systematic literature search of clinical studies published from 1995 to 2015, recording fracture rate and bone mineral density (BMD) for both treatment and placebo arms. The search resulted in a metadata set comprised of 21 studies investigating the effects of various bisphosphonates, teriparatide, denosumab, and raloxifene in 65,254 patients over a cumulative 56.75 years of study. The IPD was used to augment an AD in a model-based meta-analysis (MBMA) hierarchical modeling approach. The resulting model predicts the probability of fracture events in patients with osteoporosis. The object of model building using this approach was to promote understanding of the impact of therapeutic drug effects on the probability of fracture together with, or independent of their effects on BMD. Candidate models were evaluated by deviance information criteria and posterior predictive check. The model with covariates for lumbar spine BMD with interaction with a drug effect on BMD, and patient body mass index, years post-menopause, fracture measure method (clinical or radiological) and an additional drug effect outperformed those models without interaction and without additional drug effects. The model quantitatively supports the widely held notion that changes in bone microarchitecture, which cannot be measured by areal BMD elicited by therapy contribute in a significant way to a reduction in fracture. Furthermore, this model can be used to simulate fracture risk in a clinical cohort similar to those contained in the MBMA.

Exposure-response modelling for empagliflozin, a sodium glucose cotransporter 2 (SGLT2) inhibitor, in patients with type 2 diabetes.

AIMS: To provide model-based clinical development decision support including dose selection guidance for empagliflozin, an orally administered sodium glucose cotransporter 2 inhibitor, through developed exposure-response (E-R) models for efficacy and tolerability in patients with type 2 diabetes mellitus (T2DM). METHODS: Five randomized, placebo-controlled, multiple oral dose studies of empagliflozin in patients with T2DM (n = 974; 1-100 mg once daily, duration ≤12 weeks) were used to develop E-R models for efficacy (glycosylated haemoglobin [HbA1c ], fasting plasma glucose [FPG] and urinary glucose excretion). Two studies (n = 748, 12 weeks) were used to evaluate tolerability E-R. RESULTS: The efficacy model predicted maximal decreases in FPG and HbA1c of 16% and 0.6%, respectively, assuming a baseline FPG concentration of 8 mm (144 mg dl(-1) ) and 10-25 mg every day empagliflozin targeted 80-90% of these maximums. Increases in exposure had no effect on incidence rates of hypoglycaemia (n = 4), urinary tract infection (n = 17) or genital/vulvovaginal-related (n = 16) events, although low prevalence rates may have precluded more accurate evaluation. CONCLUSIONS: E-R analyses indicated that 10 and 25 mg once daily empagliflozin doses achieved near maximal glucose lowering efficacy.

Modeling and simulation for medical product development and evaluation: highlights from the FDA-C-Path-ISOP 2013 workshop.

Medical-product development has become increasingly challenging and resource-intensive. In 2004, the Food and Drug Administration (FDA) described critical challenges facing medical-product development by establishing the critical path initiative [1]. Priorities identified included the need for improved modeling and simulation tools, further emphasized in FDA's 2011 Strategic Plan for Regulatory Science [Appendix]. In an effort to support and advance model-informed medical-product development (MIMPD), the Critical Path Institute (C-Path) [www.c-path.org], FDA, and International Society of Pharmacometrics [www.go-isop.org] co-sponsored a workshop in Washington, D.C. on September 26, 2013, to examine integrated approaches to developing and applying model- MIMPD. The workshop brought together an international group of scientists from industry, academia, FDA, and the European Medicines Agency to discuss MIMPD strategies and their applications. A commentary on the proceedings of that workshop is presented here.

Bayesian estimation in NONMEM.

Bayesian estimation is a powerful but underutilized tool for answering drug development questions. In this tutorial, the principles of Bayesian model development, assessment, and prior selection will be outlined. An example pharmacokinetic (PK) model will be used to demonstrate the implementation of Bayesian modeling using the nonlinear mixed-effects modeling software NONMEM.

Model-based meta-analysis using latent variable modeling to set benchmarks for new treatments of systemic lupus erythematosus.

Several investigational agents are under evaluation in systemic lupus erythematosus (SLE) clinical trials but quantitative frameworks to enable comparison of their efficacy to reference benchmark treatments are lacking. To benchmark SLE treatment effects and identify clinically important covariates, we developed a model-based meta-analysis (MBMA) within a latent variable model framework for efficacy end points and SLE composite end point scores (BILAG-based Composite Lupus Assessment and Systemic Lupus Erythematosus Responder Index) using aggregate-level data on approved and investigational therapeutics. SLE trials were searched using PubMed and www.clinicaltrials.gov for treatment name, SLE and clinical trial as search criteria that resulted in four data structures: (1) study and investigational agent, (2) dose and regimen, (3) baseline descriptors, and (4) outcomes. The final dataset consisted of 25 studies and 81 treatment arms evaluating 16 different agents. A previously developed (K Goteti et al. 2022) SLE latent variable model of data from placebo arms (placebo + standard of care treatments) was used to describe aggregate SLE end points over time for the various SLE placebo and treatment arms in a Bayesian MBMA framework. Continuous dose-effect relationships using a maximum effect model were included for anifrolumab, belimumab, CC-220 (iberdomide), epratuzumab, lulizumab pegol, and sifalimumab, whereas the remaining treatments were modeled as discrete dose effects. The final MBMA model was then used to benchmark these compounds with respect to the maximal efficacy on the latent variable compared to the placebo. This MBMA illustrates the application of latent variable models in understanding the trajectories of composite end points in chronic diseases and should enable model-informed development of new investigational agents in SLE.

Multisite Assembly of Gateway Induced Clones (MAGIC): a flexible cloning toolbox with diverse applications in vertebrate model systems.

Here we present the Multisite Assembly of Gateway Induced Clones (MAGIC) system, which harnesses site-specific recombination-based cloning via Gateway technology for rapid, modular assembly of between 1 and 3 "Entry" vector components, all into a fourth, standard high copy "Destination" plasmid backbone. The MAGIC toolkit spans a range of in vitro and in vivo uses, from directing tunable gene expression, to driving simultaneous expression of microRNAs and fluorescent reporters, to enabling site-specific recombinase-dependent gene expression. All MAGIC system components are directly compatible with existing multisite gateway Tol2 systems currently used in zebrafish, as well as existing eukaryotic cell culture expression Destination plasmids, and available mammalian lentiviral and adenoviral Destination vectors, allowing rapid cross-species experimentation. Moreover, herein we describe novel vectors with flanking piggyBac transposon elements for stable genomic integration in vitro or in vivo when used with piggyBac transposase. Collectively, the MAGIC system facilitates transgenesis in cultured mammalian cells, electroporated mouse and chick embryos, as well as in injected zebrafish embryos, enabling the rapid generation of innovative DNA constructs for biological research due to a shared, common plasmid platform.

Quality and efficiency in small practices transitioning to patient centered medical homes: a randomized trial.

BACKGROUND: There is growing evidence that even small and solo primary care practices can successfully transition to full Patient Centered Medical Home (PCMH) status when provided with support, including practice redesign, care managers, and a revised payment plan. Less is known about the quality and efficiency outcomes associated with this transition. OBJECTIVE: Test quality and efficiency outcomes associated with 2-year transition to PCMH status among physicians in intervention versus control practices. DESIGN: Randomized Controlled Trial. PARTICIPANTS: Eighteen intervention practices with 43 physicians and 14 control practices with 24 physicians; all from adult primary care practices. INTERVENTIONS: Modeled on 2008 NCQA PPC®-PCMH™, intervention practices received 18 months of tailored practice redesign support; 2 years of revised payment, including up to $2.50 per member per month (PMPM) for achieving quality targets and up to $2.50 PMPM for PPC-PCMH recognition; and 18 months of embedded care management support. Controls received yearly participation payments. MAIN MEASURES: Eleven clinical quality indicators from the 2009 HEDIS process and health outcomes measures derived from patient claims data; Ten efficiency indicators based on Thomson Reuter efficiency indexes and Emergency Department (ED) Visit Ratios; and a panel of costs of care measures. KEY RESULTS: Compared to control physicians, intervention physicians significantly improved TWO of 11 quality indicators: hypertensive blood pressure control over 2 years (intervention +23 percentage points, control -2 percentage points, p =0.02) and breast cancer screening over 3 years (intervention +3.5 percentage points, control -0.4 percentage points, p =0.03). Compared to control physicians, intervention physicians significantly improved ONE of ten efficiency indicators: number of care episodes resulting in ED visits was reduced (intervention -0.7 percentage points, control + 0.5 percentage points, p = 0.002), with 3.8 fewer ED visits per year, saving approximately $1,900 in ED costs per physician, per year. There were no significant cost-savings on any of the pre-specified costs of care measures. CONCLUSIONS: In a randomized trial, we observed that some indicators of quality and efficiency of care in general adult primary care practices transitioning to PCMH status can be significantly, but modestly, improved over 2 years, although most indicators did not improve and there were no cost-savings compared with control practices. For the most part, quality and efficiency of care provided in unsupported control practices remained unchanged or worsened during the trial.

A randomized, controlled trial of implementing the patient-centered medical home model in solo and small practices.

BACKGROUND: Transition to a Patient-Centered Medical Home (PCMH) is challenging in primary care, especially for smaller practices. OBJECTIVE: To test the effectiveness of providing external supports, including practice redesign, care management and revised payment, compared to no support in transition to PCMH among solo and small (<2-10 providers) primary care practices over 2 years. DESIGN: Randomized Controlled Trial. PARTICIPANTS: Eighteen supported practices (intervention) and 14 control practices (controls). INTERVENTIONS: Intervention practices received 6 months of intensive, and 12 months of less intensive, practice redesign support; 2 years of revised payment, including cost of National Council for Quality Assurance's (NCQA) Physician Practice Connections(®)-Patient-Centered Medical Home™ (PPC(®)-PCMH™) submissions; and 18 months of care management support. Controls received yearly participation payments plus cost of PPC(®)-PCMH™. MAIN MEASURES: PPC(®)-PCMH™ at baseline and 18 months, plus intervention at 7 months. KEY RESULTS: At 18 months, 5 % of intervention practices and 79% of control practices were not recognized by NCQA; 10% of intervention practices and 7% of controls achieved PPC(®)-PCMH™ Level 1; 5% of intervention practices and 0% of controls achieved PPC(®)-PCMH™ Level 2; and 80% of intervention practices and 14% of controls achieved PPC(®)-PCMH™ Level 3. Intervention practices were 27 times more likely to improve PPC(®)-PCMH™ by one level, irrespective of practice size (p < 0.001) 95% CI (5-157). Among intervention practices, a multilevel ordinal piecewise model of change showed a significant and rapid 7-month effect (p(time7) = 0.01), which was twice as large as the sustained effect over subsequent 12 months (p(time18) = 0.02). Doubly multivariate analysis of variance showed significant differential change by condition across PPC(®)-PCMH™ standards over time (p(time x group)=0.03). Intervention practices improved eight of nine standards, controls improved three of nine (p(PPC1) = 0.009; p(PPC2) = 0.005; p(PPC3) = 0.007). CONCLUSIONS: Irrespective of size, practices can make rapid and sustained transition to a PCMH when provided external supports, including practice redesign, care management and payment reform. Without such supports, change is slow and limited in scope.

Population model-based analysis of the memory B-cell response following belimumab therapy in the treatment of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by B-cell hyperactivity and breach of tolerance. Autoreactive memory B cells, which have a decreased activation threshold and the ability to survive in absence of antigen, are believed to contribute to chronicity in autoimmune diseases like SLE. Belimumab, the first approved biological treatment of active SLE and lupus nephritis, reduces B cells dependent on B-lymphocyte stimulator protein (BLyS) for survival, whereas memory B cells are spared; several studies reported circulating memory B-cell concentrations increase following BLyS neutralization. This analysis investigated the effect of dose, demographics, and disease status on memory B-cell response after starting belimumab treatment. Population pharmacodynamic models were fitted to a pooled dataset from seven belimumab SLE trials. The optimal model was selected using maximum likelihood methods and was then refit to the data using Bayesian analysis and used to simulate memory B-cell response by belimumab dose and covariate subgroups. At the belimumab approved doses (10 mg/kg intravenously every 4 weeks, 200 mg subcutaneously every week), circulatory memory B cells increase in the first 4-8 weeks after belimumab initiation, typically returning to baseline levels over 76 weeks. The model analysis suggested belimumab stimulates memory B-cell transition from lymphoid and/or inflamed tissues into the circulation, rather than inhibiting trafficking in the reverse direction. Baseline BLyS and anti-double-stranded deoxyribonucleic acid antibody concentrations were statistically identifiable covariates of memory B-cell response, although their impact on predicting size and response duration was small.

Bayesian PBPK modeling using R/Stan/Torsten and Julia/SciML/Turing.Jl.

Physiologically-based pharmacokinetic (PBPK) models are mechanistic models that are built based on an investigator's prior knowledge of the in vivo system of interest. Bayesian inference incorporates an investigator's prior knowledge of parameters while using the data to update this knowledge. As such, Bayesian tools are well-suited to infer PBPK model parameters using the strong prior knowledge available while quantifying the uncertainty on these parameters. This tutorial demonstrates a full population Bayesian PBPK analysis framework using R/Stan/Torsten and Julia/SciML/Turing.jl.

Interventions for preventing falls in older people living in the community.

BACKGROUND: Approximately 30% of people over 65 years of age living in the community fall each year. This is an update of a Cochrane review first published in 2009. OBJECTIVES: To assess the effects of interventions designed to reduce the incidence of falls in older people living in the community. SEARCH METHODS: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (February 2012), CENTRAL (The Cochrane Library 2012, Issue 3), MEDLINE (1946 to March 2012), EMBASE (1947 to March 2012), CINAHL (1982 to February 2012), and online trial registers. SELECTION CRITERIA: Randomised trials of interventions to reduce falls in community-dwelling older people. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed risk of bias and extracted data. We used a rate ratio (RaR) and 95% confidence interval (CI) to compare the rate of falls (e.g. falls per person year) between intervention and control groups. For risk of falling, we used a risk ratio (RR) and 95% CI based on the number of people falling (fallers) in each group. We pooled data where appropriate. MAIN RESULTS: We included 159 trials with 79,193 participants. Most trials compared a fall prevention intervention with no intervention or an intervention not expected to reduce falls. The most common interventions tested were exercise as a single intervention (59 trials) and multifactorial programmes (40 trials). Sixty-two per cent (99/159) of trials were at low risk of bias for sequence generation, 60% for attrition bias for falls (66/110), 73% for attrition bias for fallers (96/131), and only 38% (60/159) for allocation concealment.Multiple-component group exercise significantly reduced rate of falls (RaR 0.71, 95% CI 0.63 to 0.82; 16 trials; 3622 participants) and risk of falling (RR 0.85, 95% CI 0.76 to 0.96; 22 trials; 5333 participants), as did multiple-component home-based exercise (RaR 0.68, 95% CI 0.58 to 0.80; seven trials; 951 participants and RR 0.78, 95% CI 0.64 to 0.94; six trials; 714 participants). For Tai Chi, the reduction in rate of falls bordered on statistical significance (RaR 0.72, 95% CI 0.52 to 1.00; five trials; 1563 participants) but Tai Chi did significantly reduce risk of falling (RR 0.71, 95% CI 0.57 to 0.87; six trials; 1625 participants).Multifactorial interventions, which include individual risk assessment, reduced rate of falls (RaR 0.76, 95% CI 0.67 to 0.86; 19 trials; 9503 participants), but not risk of falling (RR 0.93, 95% CI 0.86 to 1.02; 34 trials; 13,617 participants).Overall, vitamin D did not reduce rate of falls (RaR 1.00, 95% CI 0.90 to 1.11; seven trials; 9324 participants) or risk of falling (RR 0.96, 95% CI 0.89 to 1.03; 13 trials; 26,747 participants), but may do so in people with lower vitamin D levels before treatment.Home safety assessment and modification interventions were effective in reducing rate of falls (RR 0.81, 95% CI 0.68 to 0.97; six trials; 4208 participants) and risk of falling (RR 0.88, 95% CI 0.80 to 0.96; seven trials; 4051 participants). These interventions were more effective in people at higher risk of falling, including those with severe visual impairment. Home safety interventions appear to be more effective when delivered by an occupational therapist.An intervention to treat vision problems (616 participants) resulted in a significant increase in the rate of falls (RaR 1.57, 95% CI 1.19 to 2.06) and risk of falling (RR 1.54, 95% CI 1.24 to 1.91). When regular wearers of multifocal glasses (597 participants) were given single lens glasses, all falls and outside falls were significantly reduced in the subgroup that regularly took part in outside activities. Conversely, there was a significant increase in outside falls in intervention group participants who took part in little outside activity.Pacemakers reduced rate of falls in people with carotid sinus hypersensitivity (RaR 0.73, 95% CI 0.57 to 0.93; three trials; 349 participants) but not risk of falling. First eye cataract surgery in women reduced rate of falls (RaR 0.66, 95% CI 0.45 to 0.95; one trial; 306 participants), but second eye cataract surgery did not.Gradual withdrawal of psychotropic medication reduced rate of falls (RaR 0.34, 95% CI 0.16 to 0.73; one trial; 93 participants), but not risk of falling. A prescribing modification programme for primary care physicians significantly reduced risk of falling (RR 0.61, 95% CI 0.41 to 0.91; one trial; 659 participants).An anti-slip shoe device reduced rate of falls in icy conditions (RaR 0.42, 95% CI 0.22 to 0.78; one trial; 109 participants). One trial (305 participants) comparing multifaceted podiatry including foot and ankle exercises with standard podiatry in people with disabling foot pain significantly reduced the rate of falls (RaR 0.64, 95% CI 0.45 to 0.91) but not the risk of falling.There is no evidence of effect for cognitive behavioural interventions on rate of falls (RaR 1.00, 95% CI 0.37 to 2.72; one trial; 120 participants) or risk of falling (RR 1.11, 95% CI 0.80 to 1.54; two trials; 350 participants).Trials testing interventions to increase knowledge/educate about fall prevention alone did not significantly reduce the rate of falls (RaR 0.33, 95% CI 0.09 to 1.20; one trial; 45 participants) or risk of falling (RR 0.88, 95% CI 0.75 to 1.03; four trials; 2555 participants).No conclusions can be drawn from the 47 trials reporting fall-related fractures.Thirteen trials provided a comprehensive economic evaluation. Three of these indicated cost savings for their interventions during the trial period: home-based exercise in over 80-year-olds, home safety assessment and modification in those with a previous fall, and one multifactorial programme targeting eight specific risk factors. AUTHORS' CONCLUSIONS: Group and home-based exercise programmes, and home safety interventions reduce rate of falls and risk of falling.Multifactorial assessment and intervention programmes reduce rate of falls but not risk of falling; Tai Chi reduces risk of falling.Overall, vitamin D supplementation does not appear to reduce falls but may be effective in people who have lower vitamin D levels before treatment.

Combining patient-level and summary-level data for Alzheimer's disease modeling and simulation: a ß regression meta-analysis.

Our objective was to develop a beta regression (BR) model to describe the longitudinal progression of the 11 item Alzheimer's disease (AD) assessment scale cognitive subscale (ADAS-cog) in AD patients in both natural history and randomized clinical trial settings, utilizing both individual patient and summary level literature data. Patient data from the coalition against major diseases database (3,223 patients), the Alzheimer's disease neruroimaging initiative study database (186 patients), and summary data from 73 literature references (representing 17,235 patients) were fit to a BR drug-disease-trial model. Treatment effects for currently available acetyl cholinesterase inhibitors, longitudinal changes in disease severity, dropout rate, placebo effect, and factors influencing these parameters were estimated in the model. Based on predictive checks and external validation, an adequate BR meta-analysis model for ADAS-cog using both summary-level and patient-level data was developed. Baseline ADAS-cog was estimated from baseline MMSE score. Disease progression was dependent on time, ApoE4 status, age, and gender. Study drop out was a function of time, baseline age, and baseline MMSE. The use of the BR constrained simulations to the 0-70 range of the ADAS-cog, even when residuals were incorporated. The model allows for simultaneous fitting of summary and patient level data, allowing for integration of all information available. A further advantage of the BR model is that it constrains values to the range of the original instrument for simulation purposes, in contrast to methodologies that provide appropriate constraints only for conditional expectations.

Flexible and efficient Bayesian pharmacometrics modeling using Stan and Torsten, Part I.

Stan is an open-source probabilistic programing language, primarily designed to do Bayesian data analysis. Its main inference algorithm is an adaptive Hamiltonian Monte Carlo sampler, supported by state-of-the-art gradient computation. Stan's strengths include efficient computation, an expressive language that offers a great deal of flexibility, and numerous diagnostics that allow modelers to check whether the inference is reliable. Torsten extends Stan with a suite of functions that facilitate the specification of pharmacokinetic and pharmacodynamic models and makes it straightforward to specify a clinical event schedule. Part I of this tutorial demonstrates how to build, fit, and criticize standard pharmacokinetic and pharmacodynamic models using Stan and Torsten.

An unusual and challenging cause of small bowel bleeding: Isolated gastrointestinal blue rubber bleb nevus syndrome.

Blue rubber bleb nevus syndrome (BRBNS) is a rare disease that presents as cutaneous and extra-cutaneous vascular malformations, most commonly affecting the gastrointestinal (GI) tract. We report a case of adult onset BRBNS in an African American male with vascular lesions isolated to the jejunum without any cutaneous manifestations. Physicians should recognize that BRBNS can present without skin involvement and may have complications from visceral organ involvement. Treatment of BRBNS is mainly symptomatic and aims at preserving the GI tract as much as possible. BRBNS may also present as delayed recurrence after surgical or endoscopic interventions.

Role of PPARgamma, a nuclear hormone receptor in neuroprotection.

Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptor superfamily. PPAR-alpha is involved in wound healing, stimulation of lipid and folic acid catabolism, inflammation control, inhibition of ureagenesis and peroxisome proliferation. The PPARgamma/delta is involved wound healing, cell proliferation, embryo implantation, adipocyte differentiation, myelination alteration and apoptosis. The PPARgamma is involved in fat, lipid and calorie utilization, sugar control, inflammation control and macrophage (MQ) matutation. Homocysteine (Hcy) binds to nuclear peroxisome proliferator activated receptor. Increase in PPAR expression decreases the level of nitrotyrosine and increases endothelial nitric oxide concentration, decreases metalloproteinase activity and expression as well as elastinolysis and reverses Hcy-mediated vascular dysfunction. The PPARgamma initially recognized as a regulator of adipocyte development has become a potential therapeutic target for the treatment of diverse disorders. In addition, the activation of PPARgamma receptor ameliorates neurodegenerative disease. This review focuses on the recent knowledge of PPARgamma in neuroprotection and deals with the mechanism of neuroprotection of central nervous system disorder by PPARgamma.

Hydrogen sulfide protects against vascular remodeling from endothelial damage.

Remodeling by its very nature implied synthesis and degradation of extracellular matrix (ECM) proteins. Although oxidative stress, matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) have been implicated in vascular remodeling, the differential role of MMPs versus TIMPs and oxidative stress in vascular remodeling was unclear. TIMP-3 induced vascular cell apoptosis, therefore, we hypothesized that during vascular injury TIMP-3, MMP-9 and -12 (elastin-degrading MMP) were increased, whereas MMP-2 (constitutive MMP) and TIMP-4 (cardioprotective TIMP) decreased. Because of the potent anti-oxidant, vasorelaxing, anti-hypertensive agent, hydrogen sulfide (H2S) was used to mitigate the vascular remodeling due to the differential expression of MMP and TIMP. Carotid artery injury was created by inserting a PE-10 catheter and rotating several times before pulling out. The insertion hole was sealed. Mice were grouped: wild type (WT), wild-type damaged artery (WTD), WT+NaHS (sodium hydrogen sulfide, precursor of H2S) treatment (30 µmol/L in drinking water/6 weeks) and WTD+NaHS treatment. Carotid arteries were analyzed for oxidative stress and remodeling, by measuring super oxide dismutase-1 (SOD1), p47 (NADPH oxidase subunit), nitrotyrosine, MMPs and TIMPs by in situ immunolabeling and by Western blot analyses. The results suggested robust increase in p47, nitrotyrosine, MMP-9, MMP-12, TIMP-3 and decrease in SOD1 and MMP-2 levels in the injured arteries. The treatment with H2S ameliorated these effects. We concluded that p47, TIMP-3, MMP-9 and -12 were increased where as SOD-1, MMP-2 and TIMP-4 were decreased in the injured arteries. The treatment with H2S mitigated the vascular remodeling by normalizing the levels of redox stress, MMPs and TIMPs.

Antibiotic prophylaxis for surgery for proximal femoral and other closed long bone fractures.

BACKGROUND: Surgical site infection and other hospital-acquired infections cause significant morbidity after internal fixation of fractures. The administration of antibiotics may reduce the frequency of infections. OBJECTIVES: To determine whether the prophylactic administration of antibiotics in people undergoing surgical management of hip or other closed long bone fractures reduces the incidence of surgical site and other hospital-acquired infections. SEARCH STRATEGY: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (December 2009), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2009, Issue 4), MEDLINE (1950 to November 2009), EMBASE (1988 to December 2009), other electronic databases including the WHO International Clinical Trials Registry Platform (December 2009), conferences proceedings and reference lists of articles. SELECTION CRITERIA: Randomised or quasi-randomised controlled trials comparing any regimen of systemic antibiotic prophylaxis administered at the time of surgery, compared with no prophylaxis, placebo, or a regimen of different duration, in people with a hip fracture undergoing surgery for internal fixation or prosthetic replacement, or with any closed long bone fracture undergoing internal fixation. All trials needed to report surgical site infection. DATA COLLECTION AND ANALYSIS: Two authors independently screened papers for inclusion, assessed risk of bias and extracted data. Pooled data are presented graphically. MAIN RESULTS: Data from 8447 participants in 23 studies were included in the analyses. In people undergoing surgery for closed fracture fixation, single dose antibiotic prophylaxis significantly reduced deep surgical site infection (risk ratio 0.40, 95% CI 0.24 to 0.67), superficial surgical site infections, urinary infections, and respiratory tract infections. Multiple dose prophylaxis had an effect of similar size on deep surgical site infection (risk ratio 0.35, 95% CI 0.19 to 0.62), but significant effects on urinary and respiratory infections were not confirmed. Although the risk of bias in many studies as reported was unclear, sensitivity analysis showed that removal from the meta-analyses of studies at high risk of bias did not alter the conclusions. Economic modelling using data from one large trial indicated that single dose prophylaxis with ceftriaxone is a cost-effective intervention. Data for the incidence of adverse effects were very limited, but as expected they appeared to be more common in those receiving antibiotics, compared with placebo or no prophylaxis. AUTHORS' CONCLUSIONS: Antibiotic prophylaxis should be offered to those undergoing surgery for closed fracture fixation.

Hip protectors for preventing hip fractures in older people.

BACKGROUND: Hip fracture in older people usually results from a fall on the hip. Hip protectors have been advocated as a means to reduce the risk of hip fracture. OBJECTIVES: To determine if external hip protectors reduce the incidence of hip fractures in older people following a fall. SEARCH STRATEGY: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (January 2010), The Cochrane Library 2010, Issue 2, MEDLINE (1950 to November 2009), MEDLINE in-process (30 December 2009), EMBASE (1988 to 2009 week 52), CINAHL (1982 to February 2009), BioMed Central (January 2010) and reference lists of relevant articles. SELECTION CRITERIA: All randomised or quasi-randomised controlled trials comparing the use of hip protectors with an unprotected control group. DATA COLLECTION AND ANALYSIS: Two authors independently assessed risk of bias and extracted data. We sought additional information from trialists. Data were pooled using fixed-effect or random-effects models as appropriate. MAIN RESULTS: Pooling of data from 13 studies (11,573 participants) conducted in nursing or residential care settings found a marginally significant reduction in hip fracture risk (risk ratio (RR) 0.81, 95% confidence interval (CI) 0.66 to 0.99); statistical significance was lost following exclusion of five studies (3757 participants) assessed at high risk of bias (RR 0.93, 95% CI 0.74 to 1.18).Pooling of data from three trials (5135 community-dwelling participants) showed no evidence of reduction in hip fracture risk (RR 1.14, 95% CI 0.83 to 1.57).There was no evidence of a statistically significant effect on incidence of pelvic or other fractures, or on rate of falls. No important adverse effects of the hip protectors were reported but adherence, particularly in the long term, was poor. AUTHORS' CONCLUSIONS: The effectiveness of the provision of hip protectors in reducing the incidence of hip fracture in older people is still not clearly established, although they may reduce the rate of hip fractures if made available to frail older people in nursing care. It remains unknown from studies identified to date if these findings apply to all types of hip protectors. Some cluster-randomised trials have been associated with high risk of bias. Poor acceptance and adherence by older people offered hip protectors have been key factors contributing to the continuing uncertainty.

Trainee participation during screening colonoscopy does not affect ADR at subsequent surveillance, but may result in early follow-up.

Background and study aims Training future endoscopists is essential to meet rising demands for screening and surveillance colonoscopies. Studies have shown conflicting results regarding the influence of trainees on adenoma detection rates (ADR). It is unclear whether trainee participation during screening adversely affects ADR at subsequent surveillance and whether it alters surveillance recommendations. Patients and methods A retrospective analysis of average-risk screening colonoscopies and surveillance exams over a subsequent 10-year period was performed. The initial inclusion criteria were met by 5208 screening and 2285 surveillance exams. Patients with poor preparation were excluded. The final analysis included 7106 procedures, including 4922 screening colonoscopies and 2184 surveillance exams. Data were collected from pathology and endoscopy electronic databases. The primary outcome was the ADR with and without trainee participation. Surveillance recommendations were analyzed as a secondary outcome. Results Trainees participated in 1131 (23 %) screening and in 232 (11 %) surveillance exams. ADR did not significantly differ ( P  = 0.19) for screening exams with trainee participation (19.5 %) or those without (21.4 %). ADRs were higher at surveillance exams with (22.4 %) and without (27.5 %) trainee participation. ADR at surveillance was not adversely affected by trainee participation during the previous colonoscopy. Shorter surveillance intervals were given more frequently if trainees participated during the initial screening procedure ( P  = 0.0001). Conclusions ADR did not significantly differ in screening or surveillance colonoscopies with or without trainee participation. ADR at surveillance was not adversely affected by trainee participation during the previous screening exam. However, trainee participation may result in shorter surveillance recommendations.