Introduction and Objective: Progressive loss of beta-cell mass and function associated with islet inflammation is a key defect in type 2 diabetes (T2D). Islet amyloid, formed by aggregation of the beta-cell hormone, human islet amyloid polypeptide (hIAPP), contributes to islet inflammation and beta-cell failure in T2D, but the cellular mechanisms are still unclear. Here, we examined the effects of amyloid formation in human islets on the characteristics of islet-derived extracellular vesicles (EVs), as a potential mediator of amyloid-associated islet inflammation. Methods: Isolated human islets (purity 90-95%; dithizone) from cadaveric pancreatic donors (n=3) were cultured at normal (5.5 mmol/L) or elevated (11.1 mmol/L) glucose for 7 days. Small EVs (sEVs) were isolated from the culture medium collected on day 3 or 7, characterized by tunable resistive pulse sensing (TRPS) technique, and purity assessed by sEV markers. (Pro)hIAPP forms were detected in purified sEVs by Western blot. Islet IL-1 beta production, amyloid formation, beta-cell Fas upregulation, and apoptosis were assessed by quantitative immunolabelling. Results: Human islets progressively formed amyloid during 7-day culture at elevated (but not normal) glucose, associated with elevated islet IL-1beta production, beta-cell Fas upregulation and apoptosis. These changes correlated with increased number and size of sEVs released from amyloid-forming islets following 3- and 7-day culture. Also, sEVs released from amyloid-forming islets contained higher levels of (pro)hIAPP forms than sEVs released from islets cultured at normal glucose which did not form amyloid. Conclusion: In summary, these data show an increase in the number, size, and (pro)hIAPP content of sEVs released from amyloid-forming human islets associated with elevated islet IL-1 beta production and beta-cell apoptosis, suggesting that islet-derived sEVs may play a role in amyloid-mediated islet inflammation in T2D. R. Tyagi: None. B. Ozerklig: None. A. Saleem: None. L. Marzban: None.
Metabolic abnormalities affect clinical recovery and long-term survival in patients with acute myocardial infarction, but the underlying mechanisms remain unclear. D-dopachrome tautomerase (DDT) in cardiomyocytes protects the heart from injury during hypoxia-ischemia in mice. Our present study found that metabolic dysfunction induced by high fat diet (HFD) was associated with reduced cardiac DDT expression and aggravated cardiac injury following ischemia-reperfusion. Supplementation of DDT prior to ischemia decreased post-ischemic injury in these hearts, suggesting that DDT reduction is an important mechanism regulating post-ischemic cardiac injury associated with metabolic dysfunction. Among all the major fatty acid species in HFD, high palmitic acid (PA) triggered the expression and activation of protease activated receptor 2 (PAR2), which upregulated the transcriptional factors, CREB1 and FOXO1 leading to downregulation of DDT expression in the heart. PAR2 stimulated ERK phosphorylation, thereby upregulating CREB1 phosphorylation. Attenuation of CREB by siRNA significantly decreased FOXO1 expression and accumulation in the nucleus, thereby reducing cardiac DDT expression. Accordingly, PAR2 deficient mice exhibited normal ERK and CREB phosphorylation and DDT levels in the heart following HFD and reversed cardiac function recovery following reperfusion. Overall, our data reveal for the first time a novel role for DDT in mediating myocardial ischemia-reperfusion injury associated with metabolic dysfunction. Disclosure L. Li: None. Y. Qi: None. N. Cui: None. L. Leng: None. H. Wu: None. R. Bucala: None. D. Qi: None. Funding This study was supported by National Sciences and Engineering Research Council of Canada (NSERC: RGPIN-2017-04542) and Canadian Institutes of Health Research (CIHR Project Grant: PJT-156116).
Objective: To evaluate the benefits and risks of minimally invasive procedures in the management of patients with infertility and provide guidance to gynaecologists who manage common conditions in these patients.Target Population: Patients with infertility (inability to conceive after 12 months of unprotected intercourse) undergoing investigation and treatment.Benefits, Harms, and Costs: Minimally invasive reproductive surgery can be used to treat infertility, improve fertility treatment outcomes, or preserve fertility. All surgery has risks and associated complications. Reproductive surgery may not improve fertility outcomes and may, in some instances, damage ovarian reserve. All procedures have costs, which are borne either by the patient or their health insurance provider.Evidence: We searched English-language articles from January 2010 to May 2021 in PubMed/MEDLINE, Embase, Science Direct, Scopus, and Cochrane Library (see Appendix A for MeSH search terms).Validation Methods: The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix B (Tables B1 for definitions and B2 for interpretations of strong and conditional [weak] recommendations).
Objective: This guideline presents evidence and recommendations for cervical ripening and induction of labour. It aims to provide information to birth attendants and pregnant individuals on optimal perinatal care while avoiding unnecessary obstetrical intervention. Target Population: All pregnant patients. Benefits, Harms, and Costs: Consistent interprofessional use of the guideline, appropriate equipment, and trained professional staff enhance safe intrapartum care. Pregnant individuals and their support person(s) should be informed of the benefits and risks of induction of labour. Evidence: Literature published to March 2022 was reviewed. PubMed, CINAHL, and the Cochrane Library were used to search for systematic reviews, randomized controlled trials, and observational studies on cervical ripening and induction of labour. Grey (unpublished) literature was identified by searching the websites of health technology assessment and health technology related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. Validation Methods: The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations). Intended Audience: All providers of obstetrical care.
Purpose Our recent work has shown that bronchoalveolar lavage (BAL) lipopolysaccharide (LPS) is associated with increased risk of chronic lung allograft dysfunction (CLAD) in the absence of infection. Moreover, BAL LPS was associated with aspiration and reduced by anti-reflux surgery. As aspiration may increase CLAD risk by potentiating acute rejection (AR), we investigated whether BAL LPS is associated with AR in lung transplant recipients (LTRs). Moreover, we wanted to validate our previously identified BAL LPS cut-off that predicted CLAD in LTRs in an independent cohort. Methods LPS was measured in BAL samples in a case control cohort of 120 adult bilateral LTRs from 2010-2015 with a transbronchial biopsy within the first-year post-transplant without concurrent infection. Lung function was characterised as either spirometrically significant or stable based on the presence or absence of ≥10% concurrent drop in FEV1. AR was based on A-grade ≥ 1. Reflux episodes were measured with 24h pH-impedance testing, bile acids were measured using mass spectrometry. Cox-PH models were used to assess the relationship between BAL LPS, using our previously reported cut-off >0.48 EU/mL, and outcomes. Results LTRs with spirometrically significant AR had higher levels of BAL LPS than those with stable AR or stable no AR (Figure 1A). BAL LPS was positively associated with total reflux episodes (r=0.39; p=0.004), proximal reflux episodes (r=0.51; p<0.001), and BAL bile acid levels (r=0.25; p=0.007). BAL LPS>0.48 EU/mL was associated with an increased risk of CLAD [HR: 2.27 (1.16-4.45); p=0.02] (Figure 1B) and death/retransplantation [HR: 2.45 (1.24-4.84); p=0.01]. Conclusion We demonstrate independent validation that BAL LPS predicts CLAD. LPS mediated immune activation may explain the link between aspiration, acute rejection, and CLAD. Anti-reflux surgery in LTRs with BAL LPS>0.48 EU/mL may help reduce BAL LPS levels and prevent CLAD.
