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971.
Brilhante RS Coelho CG Sidrim JJ de Lima RA Ribeiro JF de Cordeiro RA Castelo-Branco Dde S Gomes JM Simões-Mattos L Mattos MR Beserra HE Nogueira GC Pinheiro Ade Q Rocha MF 《Mycopathologia》2012,173(2-3):193-197
The present study described clinical and epidemiological aspects of three cases of feline histoplasmosis and compared them to previously described cases. A detailed mycological identification and antifungal susceptibility profile of each isolate are presented. Secondarily, a serological survey for anti-Histoplasma antibodies was performed with domestic and wild cats. Diseased animals presented nodular to ulcerated skin lesions and respiratory disorders as main clinical signs. H. capsulatum var. capsulatum was isolated and the strains showed to be susceptible to antifungal drugs. Considering that feline histoplasmosis is uncommonly observed in veterinary clinics, diagnosis, and clinical management in endemic areas should be improved. 相似文献
972.
Nazmun Lyle Shrabana Chakrabarti Tapas Sur Antony Gomes Dipankar Bhattacharyya 《Neurochemical research》2012,37(12):2748-2757
Cold restraint stress (CRS) model exerts similar effect as physiological stress because it combines emotional stress (escape reaction) and physical stress (muscle work). It is well established that various responses to stress are regulated by sympathoadrenal system, brain monoaminergic systems and oxidative processes. Nardostachys jatamansi (NJE) is known to possess soothing and sedative action on the central nervous system. The present investigation was performed to explore the anti-stress activity of NJE on CRS model, through its effect on biochemical and neurochemical alterations. The rats were restrained in metallic chambers for 3?h at 4?°C was followed by sacrifice and assessment of stress related alterations. Hydro-ethanolic (30:70) extract of NJE was administrated orally at the doses of 200 and 500?mg/kg for 14?days and compared with vehicle control and Panax ginseng (100?mg/kg). Effects of NJE on CRS induced oxidative stress including reduced glutathione, glutathione peroxidase, glutathione reductase, glutathione-s-transferase were estimated. Dopamine, norepinephrine, serotonin and 5-hydroxy indole acetic acid were measured in the cerebral cortex, hippocampus and hypothalamus by HPLC electrochemical detector. NJE at both doses significantly inhibited CRS induced oxidative stress. It significantly mitigated CRS induced altered level of neurotransmitters in different brain regions. The study implied that NJE has the ability to provide protection against CRS induced oxidative stress and neurochemical alterations. Findings indicated that NJE revealed potent anti-stress effect implicating its therapeutic importance in stress-related disorders. 相似文献
973.
Tramontina AC Nardin P Quincozes-Santos A Tortorelli L Wartchow KM Andreazza AC Braganhol E de Souza DO Gonçalves CA 《Neurochemical research》2012,37(7):1399-1408
Diabetes mellitus is a disease associated with several changes in the central nervous system, including oxidative stress and abnormal glutamatergic neurotransmission, and the astrocytes play an essential role in these alterations. In vitro studies of astroglial function have been performed using cultures of primary astrocytes or C6 glioma cells. Herein, we investigated glutamate uptake, glutamine synthetase and S100B secretion in C6 glioma cells cultured in a high-glucose environment, as well as some parameters of oxidative stress and damage. C6 glioma cells, cultured in 12 mM glucose medium, exhibited signals of oxidative and nitrosative stress similar to those found in diabetes mellitus and other models of diabetic disease (decrease in glutathione, elevated NO, DNA damage). Interestingly, we found an increase in glutamate uptake and S100B secretion, and a decrease in glutamine synthetase, which might be linked to the altered glutamatergic communication in diabetes mellitus. Moreover, glutamate uptake in C6 glioma cells, like primary astrocytes, was stimulated by extracellular S100B. Aminoguanidine partially prevented the glial alterations induced by the 12 mM glucose medium. Together, these data emphasize the relevance of astroglia in diabetes mellitus, as well as the importance of glial parameters in the evaluation of diabetic disease progression and treatment. 相似文献
974.
Gomes SZ Lorenzon AR Vieira JS Rocha CR Bandeira C Hoshida MS Lopes LR Bevilacqua E 《Biology of reproduction》2012,86(2):56
Cytochemical localization of hydrogen peroxide-generating sites suggests NADPH (nicotinamide adenine dinucleotide 3-phosphate [reduced form]) oxidase expression at the maternal-fetal interface. To explore this possibility, we have characterized the expression and activity of the NADPH oxidase complex in trophoblast cells during the postimplantation period. Implantation sites and ectoplacental cones (EPCs) from 7.5-gestational day embryos from CD1 mice were used as a source for expression analyses of NADPH oxidase catalytic and regulatory subunits. EPCs grown in primary culture were used to investigate the production of superoxide anion through dihydroxyethidium oxidation in confocal microscopy and immunohistochemical assays. NADPH subunits Cybb (gp91phox), Cyba (p22phox), Ncf4 (p40phox), Ncf1 (p47phox), Ncf2 (p67phox), and Rac1 were expressed by trophoblast cells. The fundamental subunits of membrane CYBB and cytosolic NCF2 were markedly upregulated after phorbol-12-myristate-13-acetate (PMA) treatment, as detected by quantitative real-time PCR, Western blotting, and immunohistochemistry. Fluorescence microscopy imaging showed colocalization of cytosolic and plasma membrane NADPH oxidase subunits mainly after PMA treatment, suggesting assembly of the complex after enzyme activation. Cultured EPCs produced superoxide in a NADPH-dependent manner, associating the NADPH oxidase-mediated superoxide production with postimplantation trophoblast physiology. NADPH-oxidase cDNA subunit sequencing showed a high degree of homology between the trophoblast and neutrophil isoforms of the oxidase, emphasizing a putative role for reactive oxygen species production in phagocytic activity and innate immune responses. 相似文献
975.
Alves E Henriques BJ Rodrigues JV Prudêncio P Rocha H Vilarinho L Martinho RG Gomes CM 《Biochimica et biophysica acta》2012,1822(8):1284-1292
Following a screening on EMS-induced Drosophila mutants defective for formation and morphogenesis of epithelial cells, we have identified three lethal mutants defective for the production of embryonic cuticle. The mutants are allelic to the CG12140 gene, the fly homologue of electron transfer flavoprotein:ubiquinone oxidoreductase (ETF:QO). In humans, inherited defects in this inner membrane protein account for multiple acyl-CoA dehydrogenase deficiency (MADD), a metabolic disease of β-oxidation, with a broad range of clinical phenotypes, varying from embryonic lethal to mild forms. The three mutant alleles carried distinct missense mutations in ETF:QO (G65E, A68V and S104F) and maternal mutant embryos for ETF:QO showed lethal morphogenetic defects and a significant induction of apoptosis following germ-band elongation. This phenotype is accompanied by an embryonic accumulation of short- and medium-chain acylcarnitines (C4, C8 and C12) as well as long-chain acylcarnitines (C14 and C16:1), whose elevation is also found in severe MADD forms in humans under intense metabolic decompensation. In agreement the ETF:QO activity in the mutant embryos is markedly decreased in relation to wild type activity. Amino acid sequence analysis and structural mapping into a molecular model of ETF:QO show that all mutations map at FAD interacting residues, two of which at the nucleotide-binding Rossmann fold. This structural domain is composed by a β-strand connected by a short loop to an α-helix, and its perturbation results in impaired cofactor association via structural destabilisation and consequently enzymatic inactivation. This work thus pinpoints the molecular origins of a severe MADD-like phenotype in the fruit fly and establishes the proof of concept concerning the suitability of this organism as a potential model organism for MADD. 相似文献
976.
977.
T Rozental LF Mascarenhas R Rozenbaum R Gomes GS Mattos CC Magno DN Almeida MI Rossi AR Favacho ER Lemos 《Memórias do Instituto Oswaldo Cruz》2012,107(5):695-697
Coxiella burnetii is the agent of Q fever , an emergent worldwide zoonosis of wide clinical spectrum. Although C. burnetii infection is typically associated with acute infection, atypical pneumonia and flu-like symptoms, endocarditis, osteoarticular manifestations and severe disease are possible, especially when the patient has a suppressed immune system; however, these severe complications are typically neglected. This study reports the sequencing of the repetitive element IS1111 of the transposase gene of C. burnetii from blood and bronchoalveolar lavage (BAL) samples from a patient with severe pneumonia following methotrexate therapy, resulting in the molecular diagnosis of Q fever in a patient who had been diagnosed with active seronegative polyarthritis two years earlier. To the best of our knowledge, this represents the first documented case of the isolation of C. burnetii DNA from a BAL sample. 相似文献
978.
Andrade-Neto VV de Matos-Guedes HL Gomes DC do Canto-Cavalheiro MM Rossi-Bergmann B Torres-Santos EC 《Memórias do Instituto Oswaldo Cruz》2012,107(3):416-419
Ketoconazole is a clinically safe antifungal agent that also inhibits the growth of Leishmania spp. A study was undertaken to determine whether Leishmania parasites are prone to becoming resistant to ketoconazole by upregulating C14-demethylase after stepwise pharmacological pressure. Leishmania amazonensis promastigotes [inhibitory concentration (IC)?? = 2 μM] were subjected to stepwise selection with ketoconazole and two resistant lines were obtained, La8 (IC?? = 8 μM) and La10 (IC?? = 10 μM). As a result, we found that the resistance level was directly proportional to the C14-demethylase mRNA expression level; we also observed that expression levels were six and 12 times higher in La8 and La10, respectively. This is the first demonstration that L. amazonensis can up-regulate C14-demethylase in response to drug pressure and this report contributes to the understanding of the mechanisms of parasite resistance. 相似文献
979.
The effectiveness of antiviral treatments of chronic hepatitis B has been poorly studied in Brazil. Here, hepatitis B virus (HBV) DNA positivity, drug resistance mutations and their association with HBV genotypes were evaluated in chronically HBV-infected patients under different drug regimens in Brazil. The study involved 129 patients under interferon or nucleos(t)ide analogue therapy for a median treatment time of 12 months. One hundred and five (81%) of these patients were treated with lamivudine (LAM), either in monotherapy or in combination with newer drugs, such as entecavir (ETV) or tenofovir (TDF). High (37.5-100%) rates of HBV DNA positivity were observed with all but one drug regimen (LAM + ETV). However, patients that were treated with ETV alone, TDF alone or with LAM combination therapies had a mean viral load that was 3-4 log lower than patients treated with LAM monotherapy. Of the patients treated with LAM, 47% developed resistance mutations. HBV genotypes A (59.1%), D (30.3%) and F (9.1%) were found. There was no association between the presence of LAM resistance mutations and genotypes, HBeAg status or treatment duration. Nevertheless, the rtM204V mutation was observed more frequently (12/13, 92%) in genotype A than in the others (p = 0.023). Six out of nine isolates that contained the rtM204I mutation belonged to genotype D and half of them displayed a single mutation. Genotype D isolates with the rtM204V variant preferentially displayed a triple mutation, while genotype A preferentially displayed a double mutation (p = 0.04). 相似文献
980.