29 resultados para ACTIVE GHRELIN LEVELS
em Repositório Institucional UNESP - Universidade Estadual Paulista "Julio de Mesquita Filho"
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Aluminum (Al3+) toxicity is a major limiting factor to crop productivity in acid soils. The effects of aluminum on root and shoot growth of physic nut (Jatropha curcas L.) young plants and, the uptake and distribution of phosphorus, calcium, magnesium and aluminum in the roots and shoots were investigated in the present study. Plants were grown in 2.5L pots in a greenhouse. After fourteen days of adaptation to nutrient solution, plants were exposed to Al concentrations of 0, 370, 740, 1,100 and 1,480 mu mol L-1, corresponding to an active Al3+ solution of 13.3, 35.3, 90.0, 153.3 and 220.7 mu mol L-1, respectively. The dry matter partitioning between roots, stems and leaves, and the concentrations of P, Ca, Mg and Al in plant tissue, were measured after 75 days exposure to Al. The increasing level of Al3+ activity in solution progressively decreased the growth of the shoot and root of physic nut plants, and at the two highest active Al3+ levels, plants showed morphological abnormalities typical of the toxicity caused by this metal. Higher Al3+ activity reduced P concentrations in leaves and Ca and Mg in leaves and roots of physic nut, demonstrating the effect of Al on the uptake, transport and use of these nutrients by plants. The Al accumulated preferentially in the roots of physic nut, whereas only a small amount was transported to shoots.
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The existence of multiple active levels in a photorefractive Bi12TiO20 crystal is here investigated at 514.5nm wavelength. We carry out two-wave mixing experiments using symmetrically incident beams of equal intensities. A large amplitude fast phase modulation in one of the beams reduces the fringes visibility and improves the detection of the generated frequency modulated signals in both (R and S) output directions. Diffraction efficiencies of the phase (photorefractive) and the absorption (photochromic) gratings are quantitatively computed as functions of the grating period. Results show that the absorption grating has two distinct components: one associated to the photorefractive trap density modulation and another related to local light-induced effects between different levels. The photorefractive grating was also investigated at 633nm and 594nm (besides 514.5nm) and a significant quenching of the photorefractive effect was observed at these wavelengths.
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INTRODUÇÃO: A lipodistrofia relacionada ao uso de terapia antirretroviral (TARV) pode causar estigma estético e elevar o risco de doenças cardiovasculares. A atividade física pode ser uma alternativa válida para o tratamento e prevenção da lipodistrofia. Entretanto, poucos estudos tratam dessa temática. O objetivo deste estudo foi verificar a ocorrência de lipodistrofia relacionada ao uso de TARV em portadores de HIV/AIDS, com diferentes hábitos de atividades físicas. MÉTODOS: A casuística foi formada por 42 portadores de HIV em uso de TARV, do Centro de Testagem e Aconselhamento de Presidente Prudente. Para obtenção do nível de atividade física aplicou-se o Questionário Internacional de Atividade Física (IPAQ); a lipodistrofia foi diagnosticada pelo autorrelato do paciente e a confirmação médica. O percentual de gordura de tronco foi estimado pela absortometria por raio-X de dupla energia (DEXA). Foram coletados também dados referentes a sexo, idade, tempo de uso de TARV, valores de CD4 e carga viral. RESULTADOS: Verificou-se maior ocorrência de lipodistrofia no grupo sedentário quando comparado ao ativo, além de fator protetor da prática da atividade física em relação à ocorrência da lipodistrofia. O grupo com valores mais elevados de CD4 também apresentou maior proporção de sujeitos com lipodistrofia, além de maior proporção de ativos e de indivíduos com menor faixa etária. Os acometidos pela lipodistrofia apresentaram maiores valores de percentual de gordura de tronco, bem como, os sedentários em relação aos ativos. CONCLUSÕES: O estilo de vida fisicamente ativa resultou em efeito protetor para ocorrência da lipodistrofia relacionada ao uso da TARV.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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HIV infection is associated with disturbances in lipid metabolism due to a host's response mechanism and the current antiretroviral therapy. The pathological appearance and progression of atherosclerosis is dependent on the presence of injurious agents in the vascular endothelium and variations in different subsets of candidate genes. Therefore, the Hha I polymorphism in the apolipoprotein E gene was evaluated in addition to triglycerides, total cholesterol, very low-density lipoprotein (VLDL), LDL, high-density lipoprotein (HDL), and apolipoprotein (apo) Al, B and E levels in 86 Brazilian HIV-infected patients and 29 healthy controls. The allele frequency for apoE in the HIV-infected group and controls was in agreement with data on the Brazilian population. Dyslipidemia was observed in the HIV group and verified by increased levels of triglycerides, VLDL and apoE, and decreased levels of HDL and apoAl. The greatest abnormalities in these biochemical variables were shown in the HIV-infected individuals whose immune function was more compromised. The effect of the genetic variation at the APOE gene on biochemical variables was more pronounced in the HIV-infected individuals who carried the apoE2/3 genotype. The highly active antiretroviral therapy (HAART)-receiving group presented increased levels of total cholesterol and apoE. Dyslipidemia was a predictable consequence of HIV infection and the protease inhibitors intensified the increase in apoE values.
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The addition of a hydroxymethyl group to the antimicrobial drug nitrofurazone generated hydroxymethylnitrofurazone (NFOH), which had reduced toxicity when its activity against Trypanosoma cruzi was tested in a murine model of Chagas' disease. Four groups of 12 Swiss female mice each received 150 mg of body weight/kg/day of NFOH, 150 mg/kg/day of nitrofurazone (parental compound), 60 mg/kg/day of benznidazole (BZL), or the solvent as a placebo. Treatments were administered orally once a day 6 days a week until the completion of 60 doses. NFOH was as effective as BZL in keeping direct parasitemia at undetectable levels, and PCR results were negative. No histopathological lesions were seen 180 days after completion of the treatments, a time when the levels of anti-T. cruzi antibodies were very low in mice treated with either NFOH or BZL. Nitrofurazone was highly toxic, which led to an overall rate of mortality of 75% and necessitated interruption of the treatment. In contrast, the group treated with its hydroxymethyl derivative, NFOH, displayed the lowest mortality (16%), followed by the BZL (33%) and placebo (66%) groups. The findings of histopathological studies were consistent with these results, with the placebo group showing the most severe parasite infiltrates in skeletal muscle and heart tissue and the NFOH group showing the lowest. The present evidence suggests that NFOH is a promising anti-T. cruzi agent.
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This paper investigates a novel design approach for a vibration isolator for use in space structures. The approach used can particularly be applicable for aerospace structures that support high precision instrumentation such as satellite payloads. The isolator is a space-frame structure that is folded in on itself to act as a mechanical filter over a defined frequency range. The absence of viscoelastic elements in such a mounting makes the design suitable for use in a vacuum and in high temperature or harsh environments with no risk of drift in alignment of the structure. The design uses a genetic algorithm based geometric optimisation routine to maximise passive vibration isolation, and this is hybridised with a geometric feasibility search. To complement the passive isolation system, an active system is incorporated in the design to add damping. Experimental work to validate the feasibility of the approach is also presented, with the active/passive structure achieving transmissibility of about 19 dB over a range of 1-250 Hz. It is shown here that the use of these novel anti-vibration mountings has no or little consequent weight and cost penalties whilst maintaining their effectiveness with the vibration levels. The approach should pave the way for the design of anti-vibration mountings that can be used between most pieces of equipment and their supporting structure. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The advent of highly active antiretroviral therapy (HAART), since 1996, represented a profound impact on the natural history of HIV-infection by promoting important and sustainable viral replication suppression and increasing survival and quality of life among seropositive patients. Nonetheless, antiretroviral therapy has been observed to be accompanied by metabolic alterations such as dyslipidemia, especially hypertriglyceridemia, insulin resistance, hyperglycemia and lipodystrophy (body fat redistribution). Epidemiological studies have demonstrated a correlation between high triglyceride (TG) levels and higher incidence of coronary artery disease (CAD). Some investigators suggest dietary intervention as part of hyperlipidemia treatment, including an increase in soluble fiber intake (10-25g/day). Whereas some studies have demonstrated that both cholesterol and serum triglyceride levels decrease with the use of food fiber, others have shown just a serum triglyceride decrease, and others failed to observe any alteration in lipid metabolism. The purpose of this study was to assess the effect of soluble fiber (R) (partially hydrolyzed guar gum) supplementation on hypertriglyceridemia and immune profile in HIVpositive individuals on HAART. Nineteen HIV-positive individuals with hypertriglyceridemia (serum levels >= 150 to < 500mg/dl) were studied. of these individuals, 63.16% were males and 36.84% females, with mean age of 43.52 +/- 9.22 years. These individuals had been on the same HAART regimen for at least six months, had no change in therapy during the study and received 20g/day of soluble fiber for four months at pre-established times. Clinical-nutritional, biochemical (total proteins, albumin, globulin, total cholesterol, LDL-c, HDL-c, TG, TG/HDL-c and LDLc/HDL-c), hematimetric (hemoglobin, hematocrit and total lymphocytes), and immunologic (lymphocytes T CD4(+), T CD8(+); T CD4(+)/CD8(+) ratio, viral load, TNF-alpha and IL-6) parameters were assessed in all patients at three time points (M0: pretreatment, M1: 30 days, and M2: four months after intervention). Significance level was set at 5% for all data statistically analyzed. Serum TG and TG/HDL-c ratio reduction was observed at all time points, but statistical significance was found just at M0 and M2. The remaining biochemical, hematimetric and immunologic parameters (lymphocytes T CD4(+), T CD8(+); T CD4(+)/ CD8(+) ratio, and viral load) showed no significant difference at all times. Regarding serum cytokines, TNF-alpha and IL-6 significantly decreased between M0 and M2, and only IL-6 reduced between M1 and M2. The data collected show that dietary and anthropometric parameters remained unchanged excluding potential confounding factors related with the effect of fiber supplementation on serum TG, TNF-alpha and IL-6. Thus, soluble fiber (R) contributed to an important reduction in hypertriglyceridemia and in the serum levels of the proinflammatory cytokines TNF-alpha and IL-6 in HIV-seropositive individuals on HAART. In addition, soluble fiber (R) might have minimized the process of atherosclerosis in these individuals, given that elevated serum levels of TG, TNF-alpha and IL-6 have been associated with the development of these lesions.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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We investigated the production of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) during canine visceral leishmaniasis (VL) to gain a better understanding of the role of such multi-functional cytokines in parasite resistance. IL-6 and TNF-alpha levels were measured by capture ELISA in sera from 8 healthy dogs from a non-endemic area (control group) and in sera from 16 dogs from Aracatuba, SP, Brazil, an area endemic for leishmaniosis. The dogs from the endemic area were selected by positive ELISA serology against total Leishmania chagasi antigen, positive spleen imprints for Leishmania, and the presence of at least three clinical signs associated with active visceral leishmaniasis (fever, dermatitis, lymphoadenopathy, onychogryphosis, weight loss, cachexia, locomotory difficulty, conjunctivitis, epistaxis, hepatosplenomegaly, edema, and apathy).Enhanced systemic IL-6 production was found in sera from dogs with the active disease compared to healthy dogs (t-test, P < 0.05). In contrast, TNF-alpha did not differ between the two groups studied. There was no correlation between IL-6 production and anti-leishmanial antibody titers in the sera. Our findings suggest that IL-6 is a good marker of active disease during leishmaniasis, and that other cytokines may be involved in the hypergammaglobulinemia characteristic of canine visceral leishmaniasis. (c) 2006 Published by Elsevier B.V.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Paracoccidioidomycosis patients present an antigen-specific Th1 immunosuppression. To better understand this phenomenon, we evaluated the interleukin (IL)-12 pathway by measuring IL-12p70 production and CD3(+) T cell expression of the IL-12 receptor (IL-12R)beta1/beta2 chains, induced with the main fungus antigen (gp43) and a control antigen, from Candida albicans (CMA). We showed that gp43-induced IL-12p70 production and IL-12Rbeta2 expression were significantly decreased in acute and chronic patients as compared to healthy subjects cured from PCM or healthy infected subjects from endemic areas. Interestingly, the healthy infected Subjects had higher gp43-induced IL12p70 production and beta2 expression than the cured subjects. The addition of a neutralizing anti-IL-10 antibody to the cultures increased IL12p70 levels and beta2 expression in acute and chronic patients to levels observed in Cured subjects. Conversely, addition of the cytokine IL-10 strongly inhibited both parameters in the latter group. In conclusion, we have shown that paracoccidioidomycosis-related Th1 immunosuppression is associated with down-modulation of the IL-12 pathway, that IL-10 may participate in this process, and that patients cured from paracoccidioidomycosis may not fully recover their immune responsiveness. (C) 2004 Elsevier B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Cell-mediated and humoral immunity were studied in seventeen patients with toxic multinodular goitre, ten with active Graves' disease and fourteen healthy controls. The study included determination of sheep erythrocyte and complement rosette-forming cells in peripheral blood, immunoglobulin levels, titres of microsomal antibodies and migration inhibition test using thyroid extract and phytohaemagglutinin. When compared with controls the patients showed a positive response to thyroid antigen in the leucocyte migration inhibition test. Microsomal antibodies were detected in seven out of ten active Graves' disease patients against two out of seventeen of those with toxic multinodular goitre. Significantly increased IgG and IgA and decreased IgM levels were found only in the toxic multinodular group. These data provide further evidence for immunological disturbances in toxic multinodular goitre.