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AbstractBackgroundTo date, genetic‐association studies of single nucleotide polymorphisms (SNP) in selected candidate genes with the symptom phenotype of irritable bowel syndrome (IBS) have typically involved hundreds to 2000 patients. SNPs in immune‐related genes, such as cytokine and cytokine receptor encoding genes, have been reported to associate with IBS risk.MethodsWe conducted two independent case–control studies on 16 SNPs in IL1R1, IL4, IL6, IL8, IL10, IL23R, TNFA, and TNFSF15, one from the UK (194 patients and 92 healthy volunteers) and one from the USA (137 patients and 96 healthy volunteers). The main aim was to examine the relationship between inherited immunological diversity and IBS risk in a meta‐analysis which included 12 additional, earlier studies. The meta‐analysis comprised a total of 2894 patients (839 IBS‐C, 1073 IBS‐D, 502 IBS‐M), and 3138 healthy volunteers with self‐reported Caucasian ancestry.Key ResultsThe association of SNP rs4263839 (TNFSF15) was investigated in four studies and confirmed in the meta‐analysis: IBS (OR 1.19, 95% CI 1.08–1.31), and IBS‐C (OR 1.24, 95% CI 1.08–1.42). No additional SNPs residing in immunogenes associated with IBS symptom phenotypes.Conclusions & InferencesOur meta‐analysis could not confirm a major role of most investigated SNPs, but a moderate association between rs4263839 TNFSF15 and IBS, in particular IBS‐C. The analysis emphasizes the importance of definition and phenotype homogeneity, adequate study size and representativeness of the patient and control collective.

Background and aim Although Non-steroidal anti-inflammatory drugs reduce colorectal adenoma burden in familial adenomatous polyposis (FAP), the utility of combining chemopreventive agents in FAP is not known. We conducted a randomised trial of celecoxib (CXB) versus CXB+diflouromethylornithine (DFMO) to determine the synergistic effect, if any. Methods The primary endpoint was % change in adenoma count in a defined field. Secondary endpoints were adenoma burden (weighted by adenoma diameter) and video review of entire colon/rectal segments. Adverse event (AEs) were monitored by National Cancer Institution toxicity criteria. Results 112 subjects were randomised: 60 men and 52 women at a mean age of 38 years. For the 89 patients who had landmark-matched polyp counts available at baseline and 6 months, the mean % change in adenoma count over the 6 months of trial was −13.0% for CXB+DFMO and −1.0% for CXB (p=0.69). Mean % change in adenoma burden was −40% (CXB+DFMO) vs −27% (CXB) (p=0.13). Video-based global polyp change was −0.80 for CXB+DFMO vs −0.33 for CXB (p=0.03). Fatigue was the only significant AE, worse on the CXB arm (p=0.02). Conclusions CXB combined with DFMO yielded moderate synergy according to a video-based global assessment. No significant difference in adenoma count, the primary endpoint, was seen between the two study arms. No evidence of DFMO-related ototoxicity was seen. There were no adverse cardiovascular outcomes in either trial arm and no significant increase in AEs in the CXB+DFMO arm of the trial. Differences in outcomes between primary and secondary endpoints may relate to sensitivity of the endpoint measures themselves. Trial registration number ClinicalTrials.gov number N01-CN95040.

Objectives. We sought to describe the prevalence of a hyaluronidase gene and hyaluronidase production in 197 clinical isolates ofP. acnes; we assessed kinetics of hyaluronidase production in a subset of three isolates.Methods. The hyaluronidase gene was detected using polymerase chain reaction. Hyaluronidase production was detected by growing isolates on BHI agar containing 400 μg/mL hyaluronic acid and 1% albumin and flooding plates with 2 N glacial acetic acid to precipitate unbound hyaluronic acid, with a zone of clearing representing a positive phenotype. Hyaluronidase production kinetics were measured as a function of hyaluronic acid digestion over time in a liquid medium.Results. A hyaluronidase gene and hyaluronidase production were detected in 100 and 97% ofP. acnesisolates, respectively. Hyaluronidase production in liquid medium was detectable after 96 hours of growth.Conclusions. Hyaluronidase production is nearly universal amongP. acnesisolates. Three days appear to be required for significant hyaluronidase production in a liquid medium. Detection of hyaluronidase in tissue specimens may be a strategy to differentiateP. acnesinfection from colonization whenP. acnesis isolated from a clinical specimen.

Circadian rhythm dysfunction is linked to many diseases, yet pathophysiological roles in articular cartilage homeostasis and degenerative joint disease including osteoarthritis (OA) remains to be investigated in vivo. Here, we tested whether environmental or genetic disruption of circadian homeostasis predisposes to OA‐like pathological changes. Male mice were examined for circadian locomotor activity upon changes in the light:dark (LD) cycle or genetic disruption of circadian rhythms. Wild‐type (WT) mice were maintained on a constant 12 h:12 h LD cycle (12:12 LD) or exposed to weekly 12 h phase shifts. Alternatively, male circadian mutant mice ( Clock Δ19 or Csnk1e tau mutants) were compared with age‐matched WT littermates that were maintained on a constant 12:12 LD cycle. Disruption of circadian rhythms promoted osteoarthritic changes by suppressing proteoglycan accumulation, upregulating matrix‐degrading enzymes and downregulating anabolic mediators in the mouse knee joint. Mechanistically, these effects involved activation of the PKCδ‐ERK‐RUNX2/NFκB and β‐catenin signaling pathways, stimulation of MMP‐13 and ADAMTS‐5, as well as suppression of the anabolic mediators SOX9 and TIMP‐3 in articular chondrocytes of phase‐shifted mice. Genetic disruption of circadian homeostasis does not predispose to OA‐like pathological changes in joints. Our results, for the first time, provide compelling in vivo evidence that environmental disruption of circadian rhythms is a risk factor for the development of OA‐like pathological changes in the mouse knee joint. J. Cell. Physiol. 230: 2174–2183, 2015. © 2015 Wiley Periodicals, Inc.

Significance Butyrylcholinesterase (BChE), a common plasma enzyme, has been known for decades but its real physiological roles are just beginning to emerge. Although BChE eliminates the neurotransmitter acetylcholine, it is not vital for locomotion, cognition, or other cholinergic functions. Nevertheless, we now find that circulating BChE has a large impact on aggressive behavior in mice that is attributable to its ability to inactivate ghrelin, a peptide hormone involved in hunger, feeding, and stress. A key observation was decreased fighting among group-housed male mice overexpressing BChE after viral gene transfer. In contrast, BChE knockout mice exhibited increased fighting. These effects mirrored changes in plasma levels of active ghrelin. Controlling them might offer therapeutic potential for certain behavioral disorders.

ABSTRACT A process employing patient- or parent-collected pharyngeal swabs for group A Streptococcus (GAS) testing would expedite diagnosis and treatment, reduce patient exposure to the health care setting, and decrease health care costs. Our aim was to determine the concordance between patient- or parent-collected (self-collected) and health care worker (HCW)-collected pharyngeal swabs for detection of GAS by PCR. From 9 October 2012 to 21 March 2013, patients presenting with a sore throat meeting criteria for GAS testing and not meeting criteria for severe disease were offered the opportunity to collect their own pharyngeal swab. The HCW also collected a swab. Paired swabs were tested by GAS real-time PCR, allowing semiquantitative comparisons between positive results. Of the 402 participants, 206 had a swab collected by the patient and 196 a swab collected by the parent. The percent positivity results were 33.3% for HCW-collected swabs and 34.3% for self-collected swabs ( P = 0.41). The overall concordance between the two collection strategies was 94.0% (95% confidence interval [CI], 91.3 to 96.0). Twenty-four of the paired swabs had discordant results, with 10 and 14 positives detected only with the HCW- and self-collected swabs, respectively ( P = 0.41). The person collecting the swab in the self-collected arm, the order of collection, and prior swab collection training did not influence results. Among the 124 specimens that were positive by both collection methods, the amount of GAS DNA was higher in the self-collected versus the HCW-collected swabs ( P = 0.008). Self-collected pharyngeal swabs provide a reliable alternative to HCW collection for detection of GAS and offer a strategy for improved health care delivery.

Background and Purpose— NINDS (National Institute of Neurological Disorders and Stroke)-SiGN (Stroke Genetics Network) is an international consortium of ischemic stroke studies that aims to generate high-quality phenotype data to identify the genetic basis of pathogenic stroke subtypes. This analysis characterizes the etiopathogenetic basis of ischemic stroke and reliability of stroke classification in the consortium. Methods— Fifty-two trained and certified adjudicators determined both phenotypic (abnormal test findings categorized in major pathogenic groups without weighting toward the most likely cause) and causative ischemic stroke subtypes in 16 954 subjects with imaging-confirmed ischemic stroke from 12 US studies and 11 studies from 8 European countries using the web-based Causative Classification of Stroke System. Classification reliability was assessed with blinded readjudication of 1509 randomly selected cases. Results— The distribution of pathogenic categories varied by study, age, sex, and race ( P <0.001 for each). Overall, only 40% to 54% of cases with a given major ischemic stroke pathogenesis (phenotypic subtype) were classified into the same final causative category with high confidence. There was good agreement for both causative (κ 0.72; 95% confidence interval, 0.69–0.75) and phenotypic classifications (κ 0.73; 95% confidence interval, 0.70–0.75). Conclusions— This study demonstrates that pathogenic subtypes can be determined with good reliability in studies that include investigators with different expertise and background, institutions with different stroke evaluation protocols and geographic location, and patient populations with different epidemiological characteristics. The discordance between phenotypic and causative stroke subtypes highlights the fact that the presence of an abnormality in a patient with stroke does not necessarily mean that it is the cause of stroke.