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231.
Amado LA Villar LM de Paula VS de Almeida AJ Gaspar AM 《Memórias do Instituto Oswaldo Cruz》2006,101(2):149-155
In this report, we examine the adaptability of commercially available serological kits to detect antibodies markers for viral hepatitis in oral fluid samples. We also assessed the prevalence of hepatitis A, B, and C virus-specific antibodies, and related risk factors for these infectious diseases through sensitivity of the tests in saliva samples to evaluate if oralfluid can be an alternative tool to substitute serum in diagnosis of acute viral hepatitis and in epidemiological studies. One hundred and ten paired serum and saliva specimens from suspect patients of having acute hepatitis were collected to detect antibodies to hepatitis A (total and IgM), hepatitis B (anti-HBs, total anti-HBc and IgM anti-HBc), and hepatitis C (anti-HCV) using commercially available enzyme-linked immunossorbent assay (EIA). In relation to serum samples, oral fluid assay sensitivity and specificity were as follows: 87 and 100% for total anti-HAV, 79 and 100% for anti-HAVIgM, 6 and 95% for anti-HBs, 13 and 100%for total anti-HBc, 100 and 100% for anti-HBc IgM, and 75 and 100% for anti-HCV The consistency observed between antibodies tests in saliva and expected risk factors for hepatitis A and C suggests that the saliva method could replace serum in epidemiological studies for hepatitis A and C. 相似文献
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234.
Feksa LR Latini A Rech VC Wajner M Dutra-Filho CS de Souza Wyse AT Wannmacher CM 《Neurochemistry international》2006,49(1):87-93
Despite the significant brain abnormalities, the neurotoxic mechanisms of brain injury in hypertryptophanemia are virtually unknown. In this work, it was investigated the in vitro effect of l-tryptophan on various parameters of oxidative stress, namely spontaneous chemiluminescence, thiobarbituric acid-reactive substances (TBA-RS), total radical-trapping antioxidant potential (TRAP), total antioxidant reactivity (TAR) and glutathione (GSH) levels in cerebral cortex from 30-day-old rats. Tryptophan significantly increased chemiluminescence and TBA-RS measurements indicating that this amino acid induced lipid peroxidation in vitro. We also observed that tryptophan significantly decreased the brain antioxidant defenses by reducing the values of TRAP, TAR and GSH, reflecting that the overall content of antioxidants was reduced by tryptophan. Furthermore, the tryptophan-induced increase of TBA-RS was fully prevented by GSH and by combination of catalase plus superoxide dismutase, but not by the inhibitor of nitric oxide synthase N(omega)-nitro-L-arginine methyl ester (L-NAME). In case these findings also occur in human hypertryptophanemia or in other neurodegenerative diseases in which tryptophan accumulates, it is feasible that oxidative stress may be involved in the mechanism leading to the brain injury observed in patients affected by these disorders. 相似文献
235.
Leijiane F. Sousa Carolina A. Nicolau Pedro S. Peixoto Juliana L. Bernardoni Samella S. Oliveira José Antonio Portes-Junior Rosa Helena V. Mour?o Isa Lima-dos-Santos Ida S. Sano-Martins Hipócrates M. Chalkidis Richard H. Valente Ana M. Moura-da-Silva 《PLoS neglected tropical diseases》2013,7(9)
In Latin America, Bothrops snakes account for most snake bites in humans, and the recommended treatment is administration of multispecific Bothrops antivenom (SAB – soro antibotrópico). However, Bothrops snakes are very diverse with regard to their venom composition, which raises the issue of which venoms should be used as immunizing antigens for the production of pan-specific Bothrops antivenoms. In this study, we simultaneously compared the composition and reactivity with SAB of venoms collected from six species of snakes, distributed in pairs from three distinct phylogenetic clades: Bothrops, Bothropoides and Rhinocerophis. We also evaluated the neutralization of Bothrops atrox venom, which is the species responsible for most snake bites in the Amazon region, but not included in the immunization antigen mixture used to produce SAB. Using mass spectrometric and chromatographic approaches, we observed a lack of similarity in protein composition between the venoms from closely related snakes and a high similarity between the venoms of phylogenetically more distant snakes, suggesting little connection between taxonomic position and venom composition. P-III snake venom metalloproteinases (SVMPs) are the most antigenic toxins in the venoms of snakes from the Bothrops complex, whereas class P-I SVMPs, snake venom serine proteinases and phospholipases A2 reacted with antibodies in lower levels. Low molecular size toxins, such as disintegrins and bradykinin-potentiating peptides, were poorly antigenic. Toxins from the same protein family showed antigenic cross-reactivity among venoms from different species; SAB was efficient in neutralizing the B. atrox venom major toxins. Thus, we suggest that it is possible to obtain pan-specific effective antivenoms for Bothrops envenomations through immunization with venoms from only a few species of snakes, if these venoms contain protein classes that are representative of all species to which the antivenom is targeted. 相似文献
236.
Juliana Caroline Butzge Christiane Pivotto Leticia Mezzomo Simone Krause Ferrão João Marcelo Astolfi Picanço Adelina Mezzari Luciane Noal Calil Renata Pereira Limberger Miriam A. Apel 《化学与生物多样性》2023,20(10):e202300663
Essential oils (EOs) are products of secondary metabolism with recognized organoleptic characteristics and biological properties. Recently, there has been a growing demand for EOs in the national and international market, mainly due to the recognition of their use as complementary medicine practices, and the increased use in the industries of pharmaceutics, cosmetics, well-being, veterinary and agroecology, boosting the productive sector. In this context, EOs from grasses of the Cymbopogon (Poaceae) are promising sources of bioactive compounds, due to their recognized biological properties, such as anti-inflammatory, antibacterial, antifungal, antidiabetic, repellent, and larvicide. Thus, the present study aims to carry out a review of the scientific literature of the main works related to the evaluation of the antifungal action of essential oils extracted from plants of the Cymbopogon genus, compiling the species that showed the best results and relating them to their main chemical constituents. This review covers the following species: C. citratus, C. flexuosus, C. winterianus, C. martinii, C. nardus, C. giganteus, C. schoenanthus, C. khasans, and C. proximus. Among them, C. citratus was the most assessed, being associated with the vast majority of studies (61.9 %), and it was also the species that showed the best results in terms of MIC. 相似文献
237.
Nazari Mateus Torres Freitag João Felipe Cavanhi Vítor Augusto Farina Colla Luciane Maria 《Reviews in Environmental Science and Biotechnology》2020,19(2):369-388
Reviews in Environmental Science and Bio/Technology - Although the production of biofuels from microalgae has numerous advantages over other raw materials, its large-scale application still comes... 相似文献
238.
Israel C. Vasconcelos Raquel M. Campos Hanna K. Schwaemmle Ana P. Masson Gustavo D. Ferrari Luciane C. Alberici Vitor M. Faa Norberto Garcia-Cairasco Adriano Sebollela 《Bioscience reports》2021,41(3)
Tau is a microtubule-associated protein (MAP) responsible for controlling the stabilization of microtubules in neurons. Tau function is regulated by phosphorylation. However, in some neurological diseases Tau becomes aberrantly hyperphosphorylated, which contributes to the pathogenesis of neurological diseases, known as tauopathies. Western blotting (WB) has been widely employed to determine Tau levels in neurological disease models. However, Tau quantification by WB should be interpreted with care, as this approach has been recognized as prone to produce artifactual results if not properly performed. In the present study, our goal was to evaluate the influence of a freeze-and-thaw cycle, a common procedure preceding WB, to the integrity of Tau in brain homogenates from rats, 3xTg-AD mice and human samples. Homogenates were prepared in ice-cold RIPA buffer supplemented with protease/phosphatase inhibitors. Immediately after centrifugation, an aliquot of the extracts was analyzed via WB to quantify total and phosphorylated Tau levels. The remaining aliquots of the same extracts were stored for at least 2 weeks at either −20 or −80°C and then subjected to WB. Extracts from rodent brains submitted to freeze-and-thaw presented a ∼25 kDa fragment immunoreactive to anti-Tau antibodies. An in-gel digestion followed by mass spectrometry (MS) analysis in excised bands revealed this ∼25 kDa species corresponds to a Tau fragment. Freeze-and-thaw-induced Tau proteolysis was detected even when extracts were stored at −80°C. This phenomenon was not observed in human samples at any storage condition tested. Based on these findings, we strongly recommend the use of fresh extracts of brain samples in molecular analysis of Tau levels in rodents. 相似文献
239.
Camille Granada Pedro Beschoren da Costa Bruno Brito Lisboa Luciano Kayser Vargas Luciane M. P. Passaglia 《Plant and Soil》2013,373(1-2):339-358