Type 2 diabetes is associated with suppression of autophagy and lipid accumulation in ß-cells.

Both type 2 diabetes (T2D) and obesity are characterized by excessive hyperlipidaemia and subsequent lipid droplet (LD) accumulation in adipose tissue. To investigate whether LDs also accumulate in ß-cells of T2D patients, we assessed the expression of PLIN2, a LD-associated protein, in non-diabetic (ND) and T2D pancreata. We observed an up-regulation of PLIN2 mRNA and protein in ß-cells of T2D patients, along with significant changes in the expression of lipid metabolism, apoptosis and oxidative stress genes. The increased LD buildup in T2D ß-cells was accompanied by inhibition of nuclear translocation of TFEB, a master regulator of autophagy and by down-regulation of lysosomal biomarker LAMP2. To investigate whether LD accumulation and autophagy were influenced by diabetic conditions, we used rat INS-1 cells to model the effects of hyperglycaemia and hyperlipidaemia on autophagy and metabolic gene expression. Consistent with human tissue, both LD formation and PLIN2 expression were enhanced in INS-1 cells under hyperglycaemia, whereas TFEB activation and autophagy gene expression were significantly reduced. Collectively, these results suggest that lipid clearance and overall homeostasis is markedly disrupted in ß-cells under hyperglycaemic conditions and interventions ameliorating lipid clearance could be beneficial in reducing functional impairments in islets caused by glucolipotoxicity.

Expanding the trauma code to other causes of hemorrhagic shock ­ ruptured abdominal aortic aneurysms

Summary: Expediting life-saving care for hemorrhagic shock through multi-disciplinary code protocols is a potential method to improve outcomes. Trauma codes have become standard of care at most tertiary care centres; however, it is unclear if similar protocols can improve delivery of care for other forms of hemorrhagic shock. We examined the feasibility of a code protocol for ruptured abdominal aortic aneurysms (RAAAs) by reviewing the literature and comparing patient outcomes for RAAA and trauma patients at our institution, where the latter have a wellestablished trauma code protocol. We show that, despite being similarly unstable, patients with RAAA experienced delays to care milestones compared with trauma patients, even when accounting for diagnostic delays. Combining these data with present understanding of factors implicated in RAAA survival, we propose that a "CodeAAA" protocol may fill an important gap in RAAA care and that further prospective studies examining the utility of such a code are warranted.

Management of aboriginal and nonaboriginal people with chronic kidney disease in Quebec: quality-of-care indicators.

OBJECTIVE: To compare quality-of-care indicators for management of patients with chronic kidney disease (CKD) and type 2 diabetes among the James Bay Cree of Northern Quebec with those among residents of Montreal, Que. DESIGN: A cross-sectional survey using medical records from patients seen between 2002 and 2008. SETTING: Predialysis clinics of the McGill University Health Centre in Montreal. PARTICIPANTS: Thirty Cree and 51 nonaboriginal patients older than 18 years of age with type 2 diabetes mellitus and estimated glomerular filtration rates of less than 60 mL/min/1.73 m2. MAIN OUTCOME MEASURES: Rates of anemia, iron deficiency, obesity, and renoprotective medication use among aboriginal and nonaboriginal patients. RESULTS: Overall, the Cree patients were younger (59 vs 68 years of age, P < .0035) and weighed more (101 vs 77 kg,P < .001). The 2 groups were prescribed medication to control blood pressure, lipids, and phosphate levels at similar rates, but the Cree patients were more likely to receive renoprotective agents (87% vs 65%, P = .04). Despite similar rates of erythropoietin supplementation, the Cree patients were at greater risk of anemia, with an adjusted risk ratio of 2.80 (95% CI 1.01 to 7.87). CONCLUSION: Cree patients with CKD were younger, weighed more, and were more likely to receive renoprotective agents. With the exception of the management of anemia, quality of CKD care was similar between the 2 groups.Anemia education for family physicians and continuous monitoring of quality indicators must be implemented in northern Quebec.

Mechanism of 2-aminopurine-stimulated mutagenesis in Escherichia coli.

2-Aminopurine (2AP), a base analog, causes both transition and frameshift mutations in Escherichia coli. The analog is thought to cause mutations by two mechanisms: directly, by mispairing with cytosine, and indirectly, by saturation of mismatch repair (MMR). The goal of this work was to measure the relative contribution of these two mechanisms to the occurrence of transition mutations. Our data suggest that, in contrast to 2-aminopurine-stimulated frameshift mutations, the majority of transition mutations are a direct effect of base mispairing.

Long-term in vitro human pancreatic islet culture using three-dimensional microfabricated scaffolds.

Human pancreatic islet in vitro culture is very challenging and requires the presence of various extra cellular matrix (ECM) components in a three-dimensional environment, which provides mechanical and biological support. The development of such an environment is vital in providing favourable conditions to preserve human islets in long-term culture. In this study, we investigated the effects of human islet culture within various three-dimensional environments; collagen I gel, collagen I gel supplemented with ECM components fibronectin and collagen IV, and microfabricated scaffold with ECM-supplemented gel. The cultured human islets were analyzed for functionality, gene expression and hormone content following long-term in vitro culture. It was clear the incorporation of ECM components within the three-dimensional support improved prolonged culture. However, long-term and highly uniform human islet culture within a microfabricated scaffold, with controlled pore structures, coupled with the presence of ECM components, displayed an insulin release profile similar to freshly isolated islets, yielding a stimulation index of approximately 1.8. Moreover, gene expression was markedly increased for all pancreatic genes, giving a approximately 50-fold elevation of insulin gene expression with respect to suspension culture. The distribution and presence of pancreatic hormones was also highly elevated. These findings provide a platform for the long-term maintenance and preservation of human pancreatic islets in vitro.