Direct reprogramming of human fibroblasts into insulin-producing cells using transcription factors.

Direct lineage reprogramming of one somatic cell into another without transitioning through a progenitor stage has emerged as a strategy to generate clinically relevant cell types. One cell type of interest is the pancreatic insulin-producing β cell whose loss and/or dysfunction leads to diabetes. To date it has been possible to create β-like cells from related endodermal cell types by forcing the expression of developmental transcription factors, but not from more distant cell lineages like fibroblasts.

Gsα-dependent signaling is required for postnatal establishment of a functional β-cell mass.

Objective: Early postnatal life is a critical period for the establishment of the functional β-cell mass that will sustain whole-body glucose homeostasis during the lifetime. β cells are formed from progenitors during embryonic development but undergo significant expansion in quantity and attain functional maturity after birth. The signals and pathways involved in these processes are not fully elucidated.

Wisp1 is a circulating factor that stimulates proliferation of adult mouse and human beta cells.

Expanding the mass of pancreatic insulin-producing beta cells through re-activation of beta cell replication has been proposed as a therapy to prevent or delay the appearance of diabetes. Pancreatic beta cells exhibit an age-dependent decrease in their proliferative activity, partly related to changes in the systemic environment. Here we report the identification of CCN4/Wisp1 as a circulating factor more abundant in pre-weaning than in adult mice.

Bis-allylic Deuterated DHA Alleviates Oxidative Stress in Retinal Epithelial Cells.

Oxidative stress plays a crucial role in developing and accelerating retinal diseases including age-related macular degeneration (AMD). Docosahexaenoic acid (DHA, C22:6, n-3), the main lipid constituent of retinal epithelial cell membranes, is highly prone to radical and enzymatic oxidation leading to deleterious or beneficial metabolites for retinal tissue. To inhibit radical oxidation while preserving enzymatic metabolism, deuterium was incorporated at specific positions of DHA, resulting in D-DHA when incorporated at position 6 and D-DHA when incorporated at the 6,9 -allylic positions.

MCM8- and MCM9 Deficiencies Cause Lifelong Increased Hematopoietic DNA Damage Driving p53-Dependent Myeloid Tumors.

Hematopoiesis is particularly sensitive to DNA damage. Myeloid tumor incidence increases in patients with DNA repair defects and after chemotherapy. It is not known why hematopoietic cells are highly vulnerable to DNA damage.

Targeting pancreatic islet PTP1B improves islet graft revascularization and transplant outcomes.

Deficient vascularization is a major driver of early islet graft loss and one of the primary reasons for the failure of islet transplantation as a viable treatment for type 1 diabetes. This study identifies the protein tyrosine phosphatase 1B (PTP1B) as a potential modulator of islet graft revascularization. We demonstrate that grafts of pancreatic islets lacking PTP1B exhibit increased revascularization, which is accompanied by improved graft survival and function, and recovery of normoglycemia and glucose tolerance in diabetic mice transplanted with PTP1B-deficient islets.

New Lipophenol Antioxidants Reduce Oxidative Damage in Retina Pigment Epithelial Cells.

Age-related macular degeneration (AMD) is a multifactorial pathology and its progression is exacerbated by oxidative stress. Oxidation and photo-oxidation reactions modify lipids in retinal cells, contribute to tissue injury, and lead to the formation of toxic adducts. In particular, autofluorescent pigments such as -retinylidene--retinylethanolamine (A2E) accumulate as lipofuscin in retinal pigment epithelial cells, contribute to the production of additional reactive oxygen species (ROS), and lead to cell degeneration.

Indocyanine green fluorescence angiography during liver and pancreas transplantation: a tool to integrate perfusion statement's evaluation.

Background: Indocyanine green (ICG) fluorescence imaging is a promising tool for intraoperative decision-making during surgical procedures, in particular to assess organs perfusion.

Methods: We used the ICG fluorescence during liver transplantations in six cirrhotic patients to help assessing the graft biliary duct perfusion in order to identify the appropriate level to perform the anastomosis. We also used ICG fluorescence also in five patients receiving kidney-pancreas transplantation to evaluate the perfusion levels of the duodenal stump of the pancreas graft.

Evaluating bevacizumab in combination with FOLFIRI after the failure of platinum-etoposide regimen in patients with advanced poorly differentiated neuroendocrine carcinoma: The PRODIGE 41-BEVANEC randomized phase II study.

Introduction: Patients with gastroenteropancreatic (GEP), metastatic or locally advanced, non-resectable, grade 3 poorly-differentiated neuroendocrine carcinoma (NEC) are treated with cisplatin (or carboplatin)-etoposide in first-line palliative chemotherapy (CT1). However, nearly all patients will develop resistance and there is no standard second-line treatment.

Aim: PRODIGE 41-BEVANEC is an academic randomized, phase II study designed to evaluate the efficacy of bevacizumab in combination with FOLFIRI after failure of CT1 in unknown primary NEC and GEP-NEC.

microRNA target prediction programs predict many false positives.

According to the current view, each microRNA regulates hundreds of genes. Computational tools aim at identifying microRNA targets, usually selecting evolutionarily conserved microRNA binding sites. While the false positive rates have been evaluated for some prediction programs, that information is rarely put forward in studies making use of their predictions.

Insulin like growth factor binding protein 7 (IGFBP7) expression is linked to poor prognosis but may protect from bone disease in multiple myeloma.

Background: Insulin like growth factor binding protein 7 (IGFBP7) is a secreted protein binding insulin like growth factor 1 (IGF-1), insulin, vascular endothelial growth factor A (VEGFA), and activin A. It antagonizes bone morphogenetic proteins and is involved in the tumour propagation of solid as well as haematological malignancies. Its role in multiple myeloma (MM) is not defined so far.

Molecular analysis of PRRT2 gene in a case of paroxysmal kinesigenic dyskinesia patient.

Paroxysmal kinesigenic dyskinesia (PKD) is an abnormal involuntary movement that is episodic or intermittent, with sudden onset, and the attacks are induced by sudden movement. Mutations in proline-rich transmembrane protein 2 (PRRT2) gene have been implicated in the cause of this disorder. This study presents a case of PKD on the basis of clinical findings supported and evidences obtained through a mutational analysis.

Acute nutrient regulation of the mitochondrial glutathione redox state in pancreatic β-cells.

The glucose stimulation of insulin secretion by pancreatic β-cells depends on increased production of metabolic coupling factors, among which changes in NADPH and ROS (reactive oxygen species) may alter the glutathione redox state (EGSH) and signal through changes in thiol oxidation. However, whether nutrients affect EGSH in β-cell subcellular compartments is unknown. Using redox-sensitive GFP2 fused to glutaredoxin 1 and its mitochondria-targeted form, we studied the acute nutrient regulation of EGSH in the cytosol/nucleus or the mitochondrial matrix of rat islet cells.

Proteasome dysfunction mediates high glucose-induced apoptosis in rodent beta cells and human islets.

The ubiquitin/proteasome system (UPS), a major cellular protein degradation machinery, plays key roles in the regulation of many cell functions. Glucotoxicity mediated by chronic hyperglycaemia is detrimental to the function and survival of pancreatic beta cells. The aim of our study was to determine whether proteasome dysfunction could be involved in beta cell apoptosis in glucotoxic conditions, and to evaluate whether such a dysfunction might be pharmacologically corrected.

Risk of colorectal high-grade dysplasia and cancer in a prospective observational cohort of patients with inflammatory bowel disease.

Background & Aims: There is an unclear risk of colonic high-grade dysplasia (HGD) and colorectal cancer (CRC) among patients with inflammatory bowel disease (IBD) treated with immunosuppressants. We analyzed data on CRC development among patients with IBD enrolled in the observational cohort Cancers et Surrisque Associé aux Maladies Inflammatoires Intestinales En France (CESAME).

Methods: We followed and collected data from 19,486 patients with IBD (60.

Efficient transduction of healthy and malignant plasma cells by lentiviral vectors pseudotyped with measles virus glycoproteins.

A lot of genes deregulated in malignant plasma cells (PCs) involved in multiple myeloma have been reported these last years. The expression of some of these genes is associated with poor survival. A critical step is to elucidate the biological mechanisms triggered by these gene products.

Dropped gallstones after laparoscopic cholecystectomy mimicking appendicitis: CT features.

We present a case in which clinical and ultrasonographic features of dropped gallstones after laparoscopic cholecystectomy mimicked appendicitis.