Heterogeneity of proliferative markers in pancreatic β-cells of patients with severe hypoglycemia following Roux-en-Y gastric bypass.

Severe postprandial hypoglycemia with neuroglycopenia is an increasingly recognized, debilitating complication of Roux-en-Y gastric bypass (RYGB) surgery. Increased secretion of insulin and incretin hormones is implicated in its pathogenesis. Histopathologic examination of pancreas has demonstrated increased islet size and/or nuclear diameter in post-RYGB patients who underwent pancreatectomy for severe refractory hypoglycemia with neuroglycopenia (RYGB + NG). We aimed to determine whether β-cell proliferation or apoptosis is altered in RYGB + NG. We performed an observational study to analyze markers of proliferation, apoptosis, cell cycle, and transcription factor expression in pancreatic tissue from affected RYGB + NG patients (n = 12), normoglycemic patients undergoing pancreatic surgery for benign lesions (controls, n = 6), and individuals with hypoglycemia due to insulinoma (n = 52). Proliferative cell nuclear antigen (PCNA) expression was increased in insulin-positive cells in RYGB + NG patients (4.5-fold increase, p < 0.001 vs. controls) and correlated with β-cell mass. Ki-67 immunoreactivity was low in both RYGB + NG and controls, but did not differ between groups. Phospho-histone H3 levels did not differ between RYGB + NG and controls. PCNA and Ki-67 were both significantly lower in both controls and RYGB + NG than insulinomas. Markers of apoptosis and cell cycle (M30, p27, and p21) did not differ between groups. PDX1 and menin exhibited similar expression patterns, while FOXO1 appeared to be more cytosolic in RYGB + NG. Markers of proliferation are heterogeneous in patients with severe post-RYGB hypoglycemia. Increased β-cell proliferation in some individuals may contribute to increased β-cell mass observed in severely affected patients

TEMPO NECESSÁRIO PARA NOVILHAS NELORE CRIADAS A PASTO, GANHAREM 210, 240, 270 KG DESDE O NASCIMENTO

O objetivo foi avaliar o número de dias para novilhas da raça Nelore (4.577) ganharem 210, 240 e 270 kg a partir do nascimento, criadas em regime de pasto. Para as análises estatísticas, utilizou-se o método dos quadrados mínimos. O modelo continha os efeitos fixos de mês e ano de nascimento da novilha e a idade da mãe como covariável; como efeito aleatório, touro aninhado dentro de fazenda e o erro. As respostas mostraram que é possível desafiar fêmeas mais jovens, com pesos menores, quando lhes são asseguradas boas condições nutricionais, e assim permitir que seu crescimento não seja interrompido. Days from birth to get 210, 240, 270 kg for nellore heifers on grazing Abstract The objective of this study was to evaluate the number of days for 4,577 nellore heifers raised in regimen of grass to get 210, 240 and 270 kg of weight since the birth. For statistical analyses, the square means method was used. The model contained the fixed effects from helfer´s month and year of birth and the dam´s age as co-variable; as random effect, bull sheltered inside the farm and the error. The results showed that it is possible to challenge younger females, with lower weight, when good nutritional conditions are assured, allowing uninterrupted growth

Understandings on the Inhibition of Oxygen Reduction Reaction by Bromide Adsorption on Pt(111) Electrodes at Different pH Values

Oxygen reduction reaction (ORR) is studied on Pt(111) in the presence of different concentrations of bromide anions at different pH values ranging from very acidic to neutral solutions. While adsorbed bromide inhibits the ORR, the strength of the inhibition decreases when the pH is increased. This is a consequence of the lower relative adsorption energy of bromide at higher pH values, caused by the lower absolute applied potential. This is reflected in a shift of the onset of the ORR (as measured with the hanging meniscus rotating disc electrode, HMRDE) to higher values as the pH is increased. HMRDE measurements reveal that the limiting current density (jlim) coincides with the theoretical value for two electrons only at very acidic solutions. However, when pH is increased, jlim tends toward the value for a four electrons reaction. From pH > 3 jlim coincides both in the presence and in the absence of bromide despite the specific anion adsorption. Experiments in solutions with different ionic strength and hydrogen peroxide reduction measurements suggest that the formation of a reaction intermediate different from H2O2 is favored at neutral pH values.This work has been financially supported by the MCINN-FEDER (Spain) through project CTQ2016-76221-P. VBM thankfully acknowledges to MINECO the award of a pre-doctoral grant (BES-2014-068176, project CTQ2013-44803-P). GABM thanks the post-doctorate fellowship from CNPq (grant no. PDE 233268/2014-6)

Svestka's Research: Then and Now

Zdenek Svestka's research work influenced many fields of solar physics, especially in the area of flare research. In this article I take five of the areas that particularly interested him and assess them in a "then and now" style. His insights in each case were quite sound, although of course in the modern era we have learned things that he could not readily have envisioned. His own views about his research life have been published recently in this journal, to which he contributed so much, and his memoir contains much additional scientific and personal information (Svestka, 2010).Comment: Invited review for "Solar and Stellar Flares," a conference in honour of Prof. Zden\v{e}k \v{S}vestka, Prague, June 23-27, 2014. This is a contribution to a Topical Issue in Solar Physics, based on the presentations at this meeting (Editors Lyndsay Fletcher and Petr Heinzel

Nonperturbative renormalization group approach to frustrated magnets

This article is devoted to the study of the critical properties of classical XY and Heisenberg frustrated magnets in three dimensions. We first analyze the experimental and numerical situations. We show that the unusual behaviors encountered in these systems, typically nonuniversal scaling, are hardly compatible with the hypothesis of a second order phase transition. We then review the various perturbative and early nonperturbative approaches used to investigate these systems. We argue that none of them provides a completely satisfactory description of the three-dimensional critical behavior. We then recall the principles of the nonperturbative approach - the effective average action method - that we have used to investigate the physics of frustrated magnets. First, we recall the treatment of the unfrustrated - O(N) - case with this method. This allows to introduce its technical aspects. Then, we show how this method unables to clarify most of the problems encountered in the previous theoretical descriptions of frustrated magnets. Firstly, we get an explanation of the long-standing mismatch between different perturbative approaches which consists in a nonperturbative mechanism of annihilation of fixed points between two and three dimensions. Secondly, we get a coherent picture of the physics of frustrated magnets in qualitative and (semi-) quantitative agreement with the numerical and experimental results. The central feature that emerges from our approach is the existence of scaling behaviors without fixed or pseudo-fixed point and that relies on a slowing-down of the renormalization group flow in a whole region in the coupling constants space. This phenomenon allows to explain the occurence of generic weak first order behaviors and to understand the absence of universality in the critical behavior of frustrated magnets.Comment: 58 pages, 15 PS figure

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02