Insulin receptor has tyrosine kinase activity toward Shc in rat liver

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOInsulin induces tyrosine phosphorylation of Shc in cell cultures and in insulin-sensitive tissues of the intact rat. However, the ability of insulin receptor (IR) tyrosine kinase to phosphorylate Shc has not been previously demonstrated. In the present study, we investigated insulin-induced IR tyrosine kinase activity towards Shc. Insulin receptor was immunoprecipitated from liver extracts, before and after a very low dose of insulin into the portal vein, and incubated with immunopurified Shc from liver of untreated rats. The kinase assay was performed in vitro in the presence of exogenous ATP and the phosphorylation level was quantified by immunoblotting with antiphosphotyrosine antibody. The results demonstrate that Shc interacted with insulin receptor after infusion of insulin, and, more important, there was insulin receptor kinase activity towards immunopurified Shc. The description of this pathway in animal tissue may have an important role in insulin receptor tyrosine kinase activity toward mitogenic transduction pathways.Insulin induces tyrosine phosphorylation of Shc in cell cultures and in insulin-sensitive tissues of the intact rat. However, the ability of insulin receptor (IR) tyrosine kinase to phosphorylate Shc has not been previously demonstrated. In the present study, we investigated insulin-induced IR tyrosine kinase activity towards Shc. Insulin receptor was immunoprecipitated from liver extracts, before and after a very low dose of insulin into the portal vein, and incubated with immunopurified Shc from liver of untreated rats. The kinase assay was performed in vitro in the presence of exogenous ATP and the phosphorylation level was quantified by immunoblotting with antiphosphotyrosine antibody. The results demonstrate that Shc interacted with insulin receptor after infusion of insulin, and, more important, there was insulin receptor kinase activity towards immunopurified Shc. The description of this pathway in animal tissue may have an important role in insulin receptor tyrosine kinase activity toward mitogenic transduction pathways311114151419FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOsem informaçã

Comunicación corta. Aflatoxina y ochratoxina A totales en hígado, riñones y plasma de pollos contaminados experimentalmente

Mycotoxicosis, particularly that caused by aflatoxins and ochratoxins, is a serious problem for the poultry production industry. The aim of this study was to determine the total aflatoxin and ochratoxin A levels in liver and plasma, and kidneys and plasma, respectively, of chickens for fattening fed experimentally contaminated diets, and to assess the impact of these toxins on body weight increase and the feed conversion ratio (FCR). Forty eight 21 day-old Ross breeder chickens (n = 12 x four treatments) were fed diets containing different levels of mycotoxins: grower diet + ochratoxin A (200 mg/kg of feed) + total aflatoxin in different concentrations (T1 = 60 microg/kg of feed; T = 50 microg/kg; T3 = 30 microg/kg). Control chickens (T4) were fed only the grower diet. No significant differences were seen in the weight increase of chickens subjected to the different treatments. However, lower FCRs were seen in those exposed to T1 and T2. In general, the amount of total aflatoxin and ochratoxin A found in the liver, kidneys and plasma (determined by ELISA) were directly related to the amounts added to the experimental diets and feed consumption. Plasma ochratoxin A was always higher than kidney levels; this relationship was not seen for total aflatoxin.Las micotoxicosis, en particular las aflatoxicosis y ocratoxicosis, son un serio problema sanitario en la producción avícola. El objetivo de este trabajo fue determinar el nivel de aflatoxinas y ochratoxinas A en hígado y plasma, y riñones y plasma, respectivamente, de pollos alimentados con dietas experimentalmente contaminadas e investigar el impacto de estas toxinas en el peso corporal y el cociente de conversión del alimento (FCR). Se alimentaron 48 pollos Ross de 21 días de edad (n = 12 x cuatro tratamientos) con dietas conteniendo diferentes niveles de micotoxinas: una dieta de crecimiento + 200 mg/kg de ochratoxina A + aflatoxina total en diferentes concentraciones (T1 = 60 microg/kg; T2 = 50 microg/kg; T3 = 30 microg/kg). Lo pollos control (T4) fueron solamente alimentados con la dieta de engorde. No hubo diferencias significativas en el aumento de peso de los pollos sometidos a los diferentes tratamientos; sin embargo, se detectaron FCRs menores para los expuestos a T1 y T2. En general, la cantidad de aflatoxina total y ochratoxina A detectadas por ELISA en hígado, riñones y plasma fueron directamente proporcionales a los niveles de las micotoxinas añadidas a las dietas experimentales. La ochratoxina A en plasma fue siempre superior a la encontrada en riñón; esta relación no se detectó para la aflatoxina total

Effects of proportional assisted ventilation on exercise performance in idiopathic pulmonary fibrosis patients

SummaryBackgroundPatients with idiopathic pulmonary fibrosis (IPF) present an important ventilatory limitation reducing their exercise capacity. Non-invasive ventilatory support has been shown to improve exercise capacity in patients with obstructive diseases; however, its effect on IPF patients remains unknown.ObjectiveThe present study assessed the effect of ventilatory support using proportional assist ventilation (PAV) on exercise capacity in patients with IPF.MethodsTen patients (61.2±9.2 year-old) were submitted to a cardiopulmonary exercise testing, plethysmography and three submaximal exercise tests (60% of maximum load): without ventilatory support, with continuous positive airway pressure (CPAP) and PAV. Submaximal tests were performed randomly and exercise capacity, cardiovascular and ventilatory response as well as breathlessness subjective perception were evaluated. Lactate plasmatic levels were obtained before and after submaximal exercise.ResultsOur data show that patients presented a limited exercise capacity (9.7±3.8mLO2/kg/min). Submaximal test was increased in patients with PAV compared with CPAP and without ventilatory support (respectively, 11.1±8.8min, 5.6±4.7 and 4.5±3.8min; p<0.05). An improved arterial oxygenation and lower subjective perception to effort was also observed in patients with IPF when exercise was performed with PAV (p<0.05). IPF patients performing submaximal exercise with PAV also presented a lower heart rate during exercise, although systolic and diastolic pressures were not different among submaximal tests. Our results suggest that PAV can increase exercise tolerance and decrease dyspnoea and cardiac effort in patients with idiopathic pulmonary fibrosis

PAISAGENS NATURAIS, GEOMORFOLOGIA COSTEIRA E DINÂMICA AMBIENTAL NO IGUAPE, AQUIRAZ-CE.

A planície litorânea do Iguape, Aquiraz-CE, constitui um ambiente de elevada vulnerabilidade ambiental, porém, vem sendo modificada sem um planejamento ambiental prévio, gerando desequilíbrios no ambiente. Avalia-se que o estudo sobre a área poderá subsidiar trabalhos de planejamento e gestão da comunidade levando em consideração suas potencialidades, fragilidades e limitações, e que possam ser realizadas ações que priorizem a conservação desses ambientes através de práticas menos impactantes

CORREDORES GEOMORFOLÓGICOS E A CIRCULAÇÃO DOS PARTICULADOS ATMOSFÉRICOS DO DISTRITO INDUSTRIAL DE PIRAPORA - MG.

Este trabalho apresenta uma análise do comportamento dos particulados atmosféricos emitidos por fontes fixas localizadas no distrito industrial de Pirapora. A dinâmica atmosférica regional marcada por ventos vindos de nordeste condiciona a movimentação preferencial dos particulados para SW. A movimentação da pluma é condicionada por dois corredores geomorfológicos:(1) direção NE-SW delimitado pela barreira orográfica na cota de 600m e (2) direção E-W na cota média de 800m

Comparison of two questionnaires which measure the health-related quality of life of idiopathic pulmonary fibrosis patients

The objective of the present study was to determine if there is a health-related quality of life (HRQL) instrument, generic or specific, that better represents functional capacity dysfunction in idiopathic pulmonary fibrosis (IPF) patients. HRQL was evaluated in 20 IPF patients using generic and specific questionnaires (Medical Outcomes Short Form 36 (SF-36) and Saint George's Respiratory Questionnaire (SGRQ), respectively). Functional status was evaluated by pulmonary function tests, 6-min walking distance test (6MWDT) and dyspnea indexes (baseline dyspnea index) at rest and after exercise (modified Borg scale). There was a restrictive pattern with impairment of diffusion capacity (total lung capacity, TLC = 71.5 ± 15.6%, forced vital capacity = 70.4 ± 19.4%, and carbon monoxide diffusing capacity = 41.5 ± 16.2% of predicted value), a reduction in exercise capacity (6MWDT = 435.6 ± 95.5 m) and an increase of perceived dyspnea score at rest and during exercise (6 ± 2.5 and 7.1 ± 1.3, respectively). Both questionnaires presented correlation with some functional parameters (TLC, forced expiratory volume in 1 s and carbon monoxide diffusing capacity) and the best correlation was with TLC. Almost all of the SGRQ domains presented a strong correlation with functional status, while in SF-36 only physical function and vitality presented a good correlation with functional status. Dyspnea index at rest and 6MWDT also presented a good correlation with HRQL. Our results suggest that a specific instead of a generic questionnaire is a more appropriate instrument for HRQL evaluation in IPF patients and that TLC is the functional parameter showing best correlation with HRQL

Dissipative Abelian Sandpiles and Random Walks

We show that the dissipative Abelian sandpile on a graph L can be related to a random walk on a graph which consists of L extended with a trapping site. From this relation it can be shown, using exact results and a scaling assumption, that the dissipative sandpiles' correlation length exponent \nu always equals 1/d_w, where d_w is the fractal dimension of the random walker. This leads to a new understanding of the known results that \nu=1/2 on any Euclidean lattice. Our result is however more general and as an example we also present exact data for finite Sierpinski gaskets which fully confirm our predictions.Comment: 10 pages, 1 figur

Instanton Effects in QCD at High Baryon Density

We study instanton effects in QCD at very high baryon density. In this regime instantons are suppressed by a large power of $(\Lambda_{QCD}/\mu)$, where $\Lambda_{QCD}$ is the QCD scale parameter and $\mu$ is the baryon chemical potential. Instantons are nevertheless important because they contribute to several physical observables that vanish to all orders in perturbative QCD. We study, in particular, the chiral condensate and its contribution $m_{GB}^2\sim m$ to the masses of Goldstone bosons in the CFL phase of QCD with $N_f=3$ flavors. We find that at densities $\rho\sim (5-10) \rho_0$, where $\rho_0$ is the density of nuclear matter, the result is dominated by large instantons and subject to considerable uncertainties. We suggest that these uncertainties can be addressed using lattice calculations of the instanton density and the pseudoscalar diquark mass in QCD with two colors. We study the topological susceptibility and Witten-Veneziano type mass relations in both $N_c=2$ and $N_c=3$ QCD.Comment: 27 pages, 8 figures, minor revision

Cosmic Chronometers: Constraining the Equation of State of Dark Energy. I: H(z) Measurements

We present new determinations of the cosmic expansion history from red-envelope galaxies. We have obtained for this purpose high-quality spectra with the Keck-LRIS spectrograph of red-envelope galaxies in 24 galaxy clusters in the redshift range 0.2 < z < 1.0. We complement these Keck spectra with high-quality, publicly available archival spectra from the SPICES and VVDS surveys. We improve over our previous expansion history measurements in Simon et al. (2005) by providing two new determinations of the expansion history: H(z) = 97 +- 62 km/sec/Mpc at z = 0.5 and H(z) = 90 +- 40 km/sec/Mpc at z = 0.8. We discuss the uncertainty in the expansion history determination that arises from uncertainties in the synthetic stellar-population models. We then use these new measurements in concert with cosmic-microwave-background (CMB) measurements to constrain cosmological parameters, with a special emphasis on dark-energy parameters and constraints to the curvature. In particular, we demonstrate the usefulness of direct H(z) measurements by constraining the dark- energy equation of state parameterized by w0 and wa and allowing for arbitrary curvature. Further, we also constrain, using only CMB and H(z) data, the number of relativistic degrees of freedom to be 4 +- 0.5 and their total mass to be < 0.2 eV, both at 1-sigma.Comment: Submitted to JCA

A New Relativistic High Temperature Bose-Einstein Condensation

We discuss the properties of an ideal relativistic gas of events possessing Bose-Einstein statistics. We find that the mass spectrum of such a system is bounded by $\mu \leq m\leq 2M/\mu _K,$ where $\mu$ is the usual chemical potential, $M$ is an intrinsic dimensional scale parameter for the motion of an event in space-time, and $\mu _K$ is an additional mass potential of the ensemble. For the system including both particles and antiparticles, with nonzero chemical potential $\mu ,$ the mass spectrum is shown to be bounded by $|\mu |\leq m\leq 2M/\mu _K,$ and a special type of high-temperature Bose-Einstein condensation can occur. We study this Bose-Einstein condensation, and show that it corresponds to a phase transition from the sector of continuous relativistic mass distributions to a sector in which the boson mass distribution becomes sharp at a definite mass $M/\mu _K.$ This phenomenon provides a mechanism for the mass distribution of the particles to be sharp at some definite value.Comment: Latex, 22 page