Ketosis-Prone Type 2 Diabetes Mellitus and<em> Human Herpesvirus 8 </em>Infection in Sub-Saharan Africans

Context: An atypical form of type 2 diabetes mellitus (DM-2) is revealed by ketosis (ketosis-prone type 2 diabetes mellitus), frequently occurring in individuals who are black and of African origin, and characterized by an acute onset requiring transient insulin therapy. Its sudden onset suggests precipitating factors. Objective: To investigate the putative role of human herpesvirus 8 (HHV-8) in the pathogenesis of ketosis-prone DM-2. Design, Setting, and Participants: A cross-sectional study in which antibodies were searched against latent and lytic HHV-8 antigens using immunofluorescence. The presence of HHV-8 in genomic DNA was investigated in 22 of the participants at clinical onset of diabetes. We also tested whether HHV-8 was able to infect human pancreatic β cells in culture in vitro. The study was conducted at Saint-Louis University Hospital, Paris, France, from January 2004 to July 2005. All participants were black and of African origin: 187 were consecutive diabetic patients of whom 81 had ketosis-prone DM-2 and 106 had nonketotic DM-2, and 90 individuals were nondiabetic control participants who were matched for age and sex. Main Outcome Measures: Seroprevalence of HHV-8 and percentage of patients with HHV-8 viremia at onset in ketosis-prone DM-2. Results: HHV-8 antibodies were found in 71 patients (87.7%) with ketosis-prone DM-2 vs 16 patients (15.1%) with nonketotic DM-2 (odds ratio, 39.9; 95% confidence interval, 17.1-93.4; P &lt; .001) and 36 of the control participants (40.0%) (odds ratio, 10.7; 95% confidence interval, 4.9-23.4; P &lt; .001). HHV-8 in genomic DNA was present in 6 of 13 patients with ketosis-prone DM-2 tested at acute onset and in 0 of 9 patients with nonketotic DM-2. HHV-8 proteins were present in human islet cells that were cultured for 4 days in the presence of HHV-8. Conclusions: In this preliminary cross-sectional study, the presence of HHV-8 antibodies was associated with ketosis-prone DM-2 in patients of sub-Saharan African origin. Longitudinal studies are required to understand the clinical significance of these findings. \ua92008 American Medical Association. All rights reserved

One-year metreleptin improves insulin secretion in patients with diabetes linked to genetic lipodystrophic syndromes

International audienceRecombinant methionyl human leptin (metreleptin) therapy was shown to improve hyperglycaemia, dyslipidaemia and insulin sensitivity in patients with lipodystrophic syndromes, but its effects on insulin secretion remain controversial. We used dynamic intravenous (i.v.) clamp procedures to measure insulin secretion, adjusted to insulin sensitivity, at baseline and after 1 year of metreleptin therapy, in 16 consecutive patients with lipodystrophy, diabetes and leptin deficiency. Patients, with a mean [± standard error of the mean (s.e.m.)] age of 39.2 (±4) years, presented with familial partial lipodystrophy (n = 11, 10 women) or congenital generalized lipodystrophy (n = 5, four women). Their mean (± s.e.m.) BMI (23.9 ± 0.7 kg/m2), glycated haemoglobin levels (8.5 ± 0.4%) and serum triglycerides levels (4.6 ± 0.9 mmol/l) significantly decreased within 1 month of metreleptin therapy, then remained stable. Insulin sensitivity (from hyperglycaemic or euglycaemic-hyperinsulinaemic clamps, n = 4 and n = 12, respectively), insulin secretion during graded glucose infusion (n = 12), and acute insulin response to i.v. glucose adjusted to insulin sensitivity (disposition index, n = 12), significantly increased after 1 year of metreleptin therapy. The increase in disposition index was related to a decrease in percentage of total and trunk body fat. Metreleptin therapy improves not only insulin sensitivity, but also insulin secretion in patients with diabetes attributable to genetic lipodystrophies

Biofluid Flow and Heat Transfer

2nd EditionInternational audienceMajor moving biological fluids, or biofluids, are blood and air that cooperate to bring oxygento the body’s cells and eliminate carbon dioxide produced by these cells. Blood is conveyed ina closed network composed of 2 circuits in series — the systemic and pulmonary circulation—, each constituted by arteries, capillaries, and veins, under the synchronized action of theleft and right cardiac pumps, respectively. Air is successively inhaled from and exhaled to theatmosphere through the airway openings (nose and/or mouth). In the head, blood generatesthe cerebrospinal fluid in choroid plexi of all compartments of the ventricular system andreceives it in arachnoid villi. Other biofluids are either secreted, such as bile from the liverand breast milk that both transport released substances with specific tasks, or excreted,such as urine from kidneys or sweat from skin glands that both convey useless materials andwaste produced by the cell metabolism. In addition to the convective transport, peristalsis,which results from the radial contraction and relaxation of mural smooth muscles, propelsthe content of the lumen of the muscular bioconduit (e.g., digestive tract) in an anterogradedirection.Blood circulation and air flow in the respiratory tract are widely explored because oftheir vital functions. Note that inhaled air is transported through the respiratory tract bytwo processes: convection down to bronchioles and diffusion down to pulmonary alveoli.1Furthermore, investigations of these physiological flows in deformable bioconduits give riseto models such as the Starling resistance that themselves become object of new study fieldsin physics and mechanics (e.g., collapsible tubes) as well as of new developments in math-ematical modeling and scientific computing. Whereas fluid–structure interaction problemsin aeronautics and civil engineering deal with materials of distinct properties, blood streamand vessel wall correspond to two domains of nearly equal physical properties, as both bloodand vessels have densities close to that of water. New processing strategies must then beconceived