A selective role for neuronal activity regulated pentraxin in the processing of sensory-specific incentive value

Neuronal activity regulated pentraxin (Narp) is a secreted neuronal product which clusters AMPA receptors and regulates excitatory synaptogenesis. Although Narp is selectively enriched in brain, its role in behavior is not known. As Narp is expressed prominently in limbic regions, we examined whether Narp deletion affects performance on tasks used to assess motivational consequences of food-rewarded learning. Narp knock-out (KO) mice were unimpaired in learning simple pavlovian discriminations, instrumental lever pressing, and in acquisition of at least two aspects of pavlovian incentive learning, conditioned reinforcement and pavlovian-instrumental transfer. In contrast, Narp deletion resulted in a substantial deficit in the ability to use specific outcome expectancies to modulate instrumental performance in a devaluation task. In this task, mice were trained to respond on two levers for two different rewards. After training, mice were prefed with one of the two rewards, devaluing it. Responding on both levers was then assessed in extinction. Whereas control mice showed a significant preference in responding on the lever associated with the nondevalued reward, Narp KO mice responded equally on both levers, failing to suppress responding on the lever associated with the devalued reward. Both groups consumed more of the nondevalued reward in a subsequent choice test, indicating Narp KO mice could distinguish between the rewards themselves. These data suggest Narp has a selective role in processing sensory-specific information necessary for appropriate devaluation performance, but not in general motivational effects of reward-predictive cues on performance

The challenges of control groups, placebos and blinding in clinical trials of dietary interventions

High-quality placebo-controlled evidence for food, nutrient or dietary advice interventions is vital for verifying the role of diet in optimising health or for the management of disease. This could be argued to be especially important where the benefits of dietary intervention are coupled with potential risks such as compromising nutrient intake, particularly in the case of exclusion diets. The objective of the present paper is to explore the challenges associated with clinical trials in dietary research, review the types of controls used and present the advantages and disadvantages of each, including issues regarding placebos and blinding. Placebo-controlled trials in nutrient interventions are relatively straightforward, as in general placebos can be easily produced. However, the challenges associated with conducting placebo-controlled food interventions and dietary advice interventions are protean, and this has led to a paucity of placebo-controlled food and dietary advice trials compared with drug trials. This review appraises the types of controls used in dietary intervention trials and provides recommendations and nine essential criteria for the design and development of sham diets for use in studies evaluating the effect of dietary advice, along with practical guidance regarding their evaluation. The rationale for these criteria predominantly relate to avoiding altering the outcome of interest in those delivered the sham intervention in these types of studies, while not compromising blinding.</jats:p

Determinants of carotid microembolization

AbstractPurpose: Earlier studies have highlighted risk factors for perioperative stroke after carotid endarterectomy, such as female sex, preoperative symptoms, and cerebral infarction. In this study, we investigated the relationship between these factors and perioperative microembolization. Methods: A total of 235 patients were entered in the study at two centers. Transcranial Doppler ultrasound scanning was possible in 190 patients (81%) and was performed for 1 hour preoperatively and continuously intraoperatively as a means of detecting microemboli and monitoring mean middle cerebral artery velocity. The findings of transcranial Doppler ultrasound scanning were related to perioperative risk factors by means of univariate analysis. Results: Microemboli were detected in 28 (15%), 79 (42%), and 98 (52%) patients preoperatively, during carotid artery dissection, and after closure of the artery, respectively. Having 10 or more emboli after carotid artery closure was more common in women (P =.04) and in patients with symptomatic carotid artery disease (P =.04) and was demonstrated in three of the six patients who had a perioperative stroke. These three patients also had preoperative evidence of cerebral infarction and an intraoperative middle cerebral artery velocity less than 40 cm/s. Conclusion: In this study, perioperative microembolization was more common in women and patients with symptomatic carotid artery disease. These findings may explain the increased risk of carotid surgery in these patients. (J Vasc Surg 2001;34:1060-4.

Faecal and urine metabolites, but not gut microbiota, may predict response to low FODMAP diet in irritable bowel syndrome

BackgroundThe low FODMAP diet (LFD) leads to clinical response in 50%-80% of patients with irritable bowel syndrome (IBS). It is unclear why only some patients respond.AimsTo determine if differences in baseline faecal microbiota or faecal and urine metabolite profiles may separate clinical responders to the diet from non-responders allowing predictive algorithms to be proposed.MethodsWe recruited adults fulfilling Rome III criteria for IBS to a blinded randomised controlled trial. Patients were randomised to sham diet with a placebo supplement (control) or LFD supplemented with either placebo (LFD) or 1.8 g/d B-galactooligosaccharide (LFD/B-GOS), for 4 weeks. Clinical response was defined as adequate symptom relief at 4 weeks after the intervention (global symptom question). Differences between responders and non-responders in faecal microbiota (FISH, 16S rRNA sequencing) and faecal (gas-liquid chromatography, gas-chromatography mass-spectrometry) and urine (1 H NMR) metabolites were analysed.ResultsAt 4 weeks, clinical response differed across the 3groups with adequate symptom relief of 30% (7/23) in controls, 50% (11/22) in the LFD group and 67% (16/24) in the LFD/B-GOS group (p = 0.048). In the control and the LFD/B-GOS groups, microbiota and metabolites did not separate responders from non-responders. In the LFD group, higher baseline faecal propionate (sensitivity 91%, specificity 89%) and cyclohexanecarboxylic acid esters (sensitivity 80%, specificity 78%), and urine metabolite profile (Q2 0.296 vs. randomised -0.175) predicted clinical response.ConclusionsBaseline faecal and urine metabolites may predict response to the LFD

Influenza Vaccine Effectiveness against Hospitalisation with Confirmed Influenza in the 2010-11 Seasons: A Test-negative Observational Study

Immunisation programs are designed to reduce serious morbidity and mortality from influenza, but most evidence supporting the effectiveness of this intervention has focused on disease in the community or in primary care settings. We aimed to examine the effectiveness of influenza vaccination against hospitalisation with confirmed influenza. We compared influenza vaccination status in patients hospitalised with PCR-confirmed influenza with patients hospitalised with influenza-negative respiratory infections in an Australian sentinel surveillance system. Vaccine effectiveness was estimated from the odds ratio of vaccination in cases and controls. We performed both simple multivariate regression and a stratified analysis based on propensity score of vaccination. Vaccination status was ascertained in 333 of 598 patients with confirmed influenza and 785 of 1384 test-negative patients. Overall estimated crude vaccine effectiveness was 57% (41%, 68%). After adjusting for age, chronic comorbidities and pregnancy status, the estimated vaccine effectiveness was 37% (95% CI: 12%, 55%). In an analysis accounting for a propensity score for vaccination, the estimated vaccine effectiveness was 48.3% (95% CI: 30.0, 61.8%). Influenza vaccination was moderately protective against hospitalisation with influenza in the 2010 and 2011 seasons

Systematic Literature Review and Meta-analysis: Real-World Mucosal Healing in Vedolizumab-Treated Patients with Crohn's Disease

Background. Vedolizumab is a gut-selective monoclonal anti-α4β7-integrin antibody approved for the treatment of adults with moderately to severely active Crohn's disease (CD). Aim. To conduct a systematic literature review and meta-analysis of published real-world studies examining mucosal healing (MH) rates in patients with CD treated with vedolizumab in routine clinical practice. Methods. MEDLINE-, Cochrane-, and EMBASE-indexed publications from January 2014 to January 2020 and 2018-2019 conference abstracts were searched for real-world studies reporting MH-related outcomes in vedolizumab-treated adults with CD. A meta-analysis was conducted in R to generate pooled estimates of MH. The primary analysis included studies reporting point estimates of MH/endoscopic remission as absence of ulcers/erosions and/or Simple Endoscopic Score for CD (SES-CD) cut − points < 4 , at 6 and 12 months. Results. The systematic literature review included 36 studies, predominantly of antitumour necrosis factor-experienced patients. MH and endoscopic remission were the most frequently reported endpoints. MH rates were 10.1%-46.0% at 6 months (ten studies) and 21.2%-62.5% at 12 months (eight studies). Fifteen studies defining MH as absence of ulcers/erosions and/or SES-CD cut − points < 4 were included for meta-analysis. Pooled MH rates for the primary analysis were 31.8% at 6 months (95% confidence interval (CI): 25.6-38.3; five studies, N = 223 ) and 33.4% at 12 months (95% CI: 25.9-41.4; three studies, N = 151 ). Conclusion. Approximately one-third of vedolizumab-treated patients with CD achieved MH at both 6 and 12 months in real-world clinical settings, despite utilisation in largely biologic-refractory patients. These findings confirm the effectiveness of vedolizumab for achieving MH in patients with CD

Regulatory T cells and immunoglobulin E: A new therapeutic link for autoimmunity?

Autoimmune diseases have a prevalence of approximately 7 to 9% and are classified as either organ-specific diseases, including type I diabetes, multiple sclerosis, inflammatory bowel disease and myasthenia gravis, or systemic diseases, including systemic lupus erythematosus, rheumatoid arthritis and Sjögren's syndrome. While many advancements have been made in understanding of the mechanisms of autoimmune disease, including the nature of self-tolerance and its breakdown, there remain unmet needs in terms of effective and highly targeted treatments. T regulatory cells (Tregs) are key mediators of peripheral tolerance and are implicated in many autoimmune diseases, either as a result of reduced numbers or altered function. Tregs may be broadly divided into those generated in the thymus (tTregs) and those generated in the periphery (pTregs). Tregs target many different immune cell subsets and tissues to suppress excessive inflammation and to support tissue repair and homeostasis: there is a fine balance between Treg cell stability and the plasticity that is required to adjust Tregs' regulatory purposes to particular immune responses. The central role of immunoglobulin E (IgE) in allergic disease is well recognized, and it is becoming increasingly apparent that this immunoglobulin also has a wider role encompassing other diseases including autoimmune disease. Anti-IgE treatment restores the capacity of plasmacytoid dendritic cells (pDCs) impaired by IgE- high-affinity IgE receptor (FcεR1) cross-linking to induce Tregs in vitro in atopic patients. The finding that antiIgE therapy restores Treg cell homeostasis, and that this mechanism is associated with clinical improvement in asthma and chronic spontaneous urticaria suggests that antiIgE therapy may also have a potential role in the treatment of autoimmune diseases in which Tregs are involved