976 resultados para Biochemical Indexes
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Polifenoloxidase (PPO, EC 1.14.18.1) extraída de folhas de Mentha arvensis foi isolada por precipitação com (NH4)2SO4 e diálise extensiva. Seu pH e temperatura ótimos variaram com o substrato. A PPO apresentou atividade com vários difenóis. Valores de Km foram 0,825; 0,928 e 7,41 mM para ácido caféico, 4-metilcatecol e catecol, respectivamente. Na inativação térmica, 50% da enzima foi inativada após 60 e 15 segundos a 70 e 75ºC, respectivamente. A medida de atividade residual mostrou um efeito estabilizante de sacarose a várias temperaturas e uma energia de ativação (Ea) para inativação aumentando com a concentração de sacarose de 0 a 40% (p/p). Valores de energias de ativação de 78,13; 80,37; 82,79 and 81,00 kJ/Mol foram encontradas para 0, 15, 30 e 40% de sacarose, respectivamente. A PPO foi inibida pelos ácidos ascórbico, benzóico, cinamico, ferulico, p-cumárico, protocatéquico, além de metabisulfito de sódio, resorcinol e pirogalol. Os valores de Ki mostram que o ácido ascórbico foi o mais efetivo inibidor. O tipo de inibição foi determinado para cada inibidor.
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This work evaluated the potential of the isoforms of methamidophos to cause organophosphorus-induced delayed neuropathy (OPIDN) in hens. In addition to inhibition of neuropathy target esterase (NTE) and acetylcholinesterase (AChE), calpain activation, spinal cord lesions and clinical signs were assessed. The isoforms (+)-, (+/-)- and (-)-methamidophos were administered at 50 mg/kg orally; tri-ortho-cresyl phosphate (TOCP) was administered (500 mg/kg, po) as positive control for delayed neuropathy. The TOCP hens showed greater than 80% and approximately 20% inhibition of NTE and AChE in hen brain, respectively. Among the isoforms of methamidophos, only the (+)-methamidophos was capable of inhibiting NTE activity (approximately 60%) with statistically significant difference compared to the control group. Calpain activity in brain increased by 40% in TOCP hens compared to the control group when measured 24h after dosing and remained high (18% over control) 21 days after dosing. Hens that received (+)-methamidophos had calpain activity 12% greater than controls. The histopathological findings and clinical signs corroborated the biochemical results that indicated the potential of the (+)-methamidophos to be the isoform responsible for OPIDN induction. Protection against OPIDN was examined using a treatment of 2 doses of nimodipine (1 mg/kg, i.m.) and one dose of calcium gluconate (5 mg/kg, iv.). The treatment decreased the effect of OPIDN-inducing TOCP and (+)-methamidophos on calpain activity, spinal cord lesions and clinical signs. (C) 2012 Elsevier B.V. All rights reserved.
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Food restriction (FR) has been shown to induce important morphological changes in rat myocardium. However, its influence on myocardial performance is not completely defined. We examined the effects of chronic FR on cardiac muscle function and morphology. Sixty-day-old Wistar-Kyoto rats were fed a control (C) or a restricted diet (daily intake reduced to 50% of the amount of food consumed by the control group) for 90 days. Myocardial performance was studied in isolated left ventricular (LV) papillary muscle. Fragments of the LV free wall were analysed by light microscopy, and the ultrastructure of the myocardium was examined in the LV papillary muscle. The myocardial collagen concentration was also evaluated. FR decreased body weight (BW) and LV weight (LVW); the LVW/BW ratio was higher in the restricted group (C, 1.86 +/- 0.17 mg/g; FR, 2.19 +/- 0.31 mg/g; p < 0.01). In the FR animals, the cardiac fibers were polymorphic, some of them were of small diameter and others presented lateral infoldings; the ultrastructural alterations were focal and included reduction of sarcoplasmic content, absence and (or) disorganization of myofilaments and Z line, numerous electron dense and polymorphic mitochondria, and deep infoldings of the plasma membrane. The hydroxyproline concentration was higher in the FR animals (p < 0.01). FR prolonged the contraction and relaxation time of the papillary muscle and did not change its ability to contract and shorten. In conclusion, although a 90-day period of FR caused striking myocardial ultrastructural alterations and increased the collagen concentration, it only minimally affected the mechanical function.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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OBJETIVOS: propor padrão de normalidade das dimensões do IVventrículo e estudar suas características em neurocisticercose. MÉTODO: em um grupo controle (GC) constituído de 114 indivíduos com tomografias normais e em outro grupo composto de 80 doentes com neurocisticercose (GN), mediram-se a distância fronto-polar de ventrículos laterais (FP) e os diâmetros craniano interno (Cr), ântero-posterior (AP) e látero-lateral (LL) do IVº ventrículo para a padronização de seis índices. RESULTADOS: AP/Cr, AP/LL e AP/FP foram os índices mais discriminatórios e apresentaram, em GC, valores médios de 0,063, 0,267 e 0,582, respectivamente. em GN os valores foram estatisticamente superiores a GC. Selecionaram-se 51 doentes do GN com índice> ou =2 desvios-padrão da média em GC. Neles, AP/Ll foi> ou =1 em 95% doentes com derivação liquórica e em 88% com depressão, ocorrendo em 73% com evolução satisfatória e todos que faleceram. CONCLUSÃO: AP/Cr, AP/LL e, principalmente, AP/FP são representativos das dimensões do IVventrículo.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Three semen samples were collected at 48 It intervals from 20 mature research dogs previously conditioned to manual semen collection. Vasectomy was performed in all dogs, and 15 days after surgery, another three ejaculates were similarly collected. The semen was evaluated, and centrifuged to obtain seminal plasma for measurement of pH, and concentrations of total proteins (TP), total chlorides (Cl), calcium (Ca), potassium (K), and sodium (Na). The seminal plasma protein profile was evaluated by SDS-PAGE; molecular weights and the integrated optical density (IOD) of each band were estimated. There was a negative correlation between K concentration and progressive motility (r = -0.49, P = 0.027), sperm vigor (r = -0.60, P = 0.0053), and plasma integrity, evaluated by both the hypo-osmotic swelling test (r = -0.50, P = 0.026) and a fluorescent stain (r = -0.45, P = 0.046). Positive correlations between Na and K pre- and post-vasectomy (r = 0.88, P < 0.001; r = 0.56, P < 0.01, respectively) were verified. There were a total of 37 bands pre-vasectomy and 35 post-vasectomy (range, 100.6-3.6 kDa). Bands B9 and B13 (42.6 and 29.2 kDa) were not present post-vasectomy. The IOD of band B3 (73.5 kDa) was higher (P 0.03) pre-vasectomy, compared to post-vasectomy; conversely, the IODs of bands B29 and B37 (7.8 and 3.6 kDa) increased (P 0.026 and 0.047). Pre-vasectomy, there was a positive correlation (r = 0.49, P = 0.029) between band B37 band (3.6 kDa) and the Na:K ratio. In conclusion, K appeared to be involved in sperm motility in dogs and could be a tool to evaluate sperm function. The prostate contributed several elements to canine seminal plasma. Vasectomy changed Ca concentrations and the protein profile of the seminal plasma. Further studies must be performed to clarify the function of these elements on the in vivo fertility of dogs. (c) 2006 Elsevier B.V. All rights reserved.