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301.
A dot-ELISA test for the detection of anti-BRSV antibodies is described. The objective of this study was the standardisation of a test as a fast, inexpensive and effective alternative to detect anti-BRSV antibodies. Its sensitivity, specificity and usefulness were compared to a commercial ELISA-kit and to the standard serum neutralisation (SN) test. The standardisation of the technique was done using nitrocellulose disks soaked with a viral sample isolated in Brazil, BRSV-25-BR. The best results were obtained when the disks were sensitised with a purified antigen at a concentration of 0.7 microg/disk and the bovine serum was diluted 1: 200. The experiment used 423 samples of bovine serum collected in the main cattle breeding centres in Brazil. The standard SN, dot-ELISA technique and commercial ELISA kits scored 67.8%, 71.8% and 72.3% of the samples as positive, respectively. When compared to the SN test, the standardised dot-ELISA and the commercial ELISA tests presented relative sensitivities of 92.3% and 91.6% and relative specificities of 71.3% and 68.4% respectively. The results demonstrated that the dot-ELISA test is adequate for the objectives proposed by this study, being easy to use and economically viable. Thus, this test represents an alternative for BRSV serological diagnosis in the substitution of SN and commercial ELISA tests, recommendable for utilisation in laboratories with few resources. 相似文献
302.
Small mammals in a mosaic of forest remnants and anthropogenic habitats—evaluating matrix quality in an Atlantic forest landscape 总被引:1,自引:0,他引:1
The matrix of altered habitats that surrounds remnants in human dominated landscapes has been considered homogeneous and inhospitable.
Recent studies, however, have shown the crucial role of the matrix in maintaining diversity in fragmented landscapes, acting
as a mosaic of units with varying permeability to different species. Inclusion of matrix quality parameters is especially
urgent in managing fragmented landscapes in the tropics where agriculture frontiers are still expanding. Using standardized
surveys in 23 sites in an Atlantic forest landscape, we evaluated matrix use by small mammals, the most diverse ecological
group of mammals in the Neotropics, and tested the hypothesis that endemic species are the most affected by the conversion
of original forest into anthropogenic habitats. By comparing species distribution among forest remnants and the predominant
adjacent habitats (native vegetation in initial stages of regeneration, eucalyptus plantations, areas of agriculture and rural
areas with buildings), we found a strong dissimilarity in small mammal assemblages between native vegetation (including initial
stages) and anthropogenic habitats, with only two species being able to use all habitats. Endemic small mammals tended to
occupy native vegetation, whereas invading species from other countries or open biomes tended to occupy areas of non-native
vegetation. Our results highlight that future destruction of native vegetation will favor invading or generalist species which
could dominate highly disturbed landscapes, and that some matrix habitats, such as regenerating native vegetation, should
be managed to increase connectivity among populations of endemic species. 相似文献
303.
Silva Alisson David Ávila Suelen Küster Renata Tulio dos Santos Mayara Padovan Grassi Marco Tadeu de Queiroz Pereira Pinto Christiane Miguel Obdulio Gomes Ferreira Sila Mary Rodrigues 《Plant foods for human nutrition (Dordrecht, Netherlands)》2021,76(4):478-486
Plant Foods for Human Nutrition - The aim of this study was to investigate the chemical composition, mineral content and report the effect of gastrointestinal digestion on the proteins, phenolics,... 相似文献
304.
Mildner-Szkudlarz Sylwia Siger Aleksander Przygoński Krzysztof Radziejewska-Kubzdela Elżbieta Zawirska-Wojtasiak Renata 《Plant foods for human nutrition (Dordrecht, Netherlands)》2022,77(2):190-197
Plant Foods for Human Nutrition - We investigated the changes in N?-(carboxymethyl)lysine (CML) and available lysine content, antioxidant properties, volatiles, and oxidation products of... 相似文献
305.
Rodrigo Otávio Silveira Silva Monique Silva Neves Márcio Garcia Ribeiro Maristela Silveira Palhares Renata de Pino Albuquerque Maranhão Francisco Carlos Faria Lobato 《Journal of Equine Veterinary Science》2014
The aim of the present study was to compare the test performances of three commercial enzyme immunoassays (EIAs) against the toxigenic culture using the cytotoxicity assay as the gold standard. All EIAs showed >78% sensitivity, and the lowest specificity was 92.6%. These results suggest that EIAs could be useful for the diagnosis of Clostridium difficile infection in foals. 相似文献
306.
Andressa Reis Alitcia Moraes Kleinowski Fátima Rosane Schuquel Klein Renata Trevizan Telles Luciano do Amarante Eugenia Jacira Bolacel Braga 《Journal of Crop Science and Biotechnology》2015,18(5):349-357
In tissue culture, several chemical and physiological factors can influence the production of secondary metabolites. The growth response and increased secondary metabolite production generated by a high irradiance environment, can be used to determine a favorable habitat for the growth and conservation of medicinal plants. Thus, the present study aimed to evaluate the influence of light quality on growth and production of secondary metabolites in Alternanthera sessilis (L.) R. Br. ex DC. (sessile joyweed), Alternanthera philoxeroides (Mart.) Grisebach (alligatorweed), Alternanthera tenella Colla (joyweed), and Alternanthera brasiliana (L.) Kuntze (Brazilian joyweed) plants cultured in vitro. The species were grown in MS medium, for 45 days in different light qualities (blue, white, and red). Growth parameters and biochemical analysis were performed at the end of the study. The results show that the red light allowed a higher accumulation of biomass in most species; red and white light were great inductors for the production of betacyanin and the blue light favored the enhancement of flavonoids. In this manner, the quality of light can affect the betacyanin, betaxanthin, and flavonoid biosynthesis as well as growth patterns in the related Alternanthera species. Based on the data presented, we suggest that specific genes can encode the pigment production according to the light quality which exhibit distinct activation patterns in different plant species. 相似文献
307.
Nisoli E Clementi E Paolucci C Cozzi V Tonello C Sciorati C Bracale R Valerio A Francolini M Moncada S Carruba MO 《Science (New York, N.Y.)》2003,299(5608):896-899
Nitric oxide was found to trigger mitochondrial biogenesis in cells as diverse as brown adipocytes and 3T3-L1, U937, and HeLa cells. This effect of nitric oxide was dependent on guanosine 3',5'-monophosphate (cGMP) and was mediated by the induction of peroxisome proliferator-activated receptor gamma coactivator 1alpha, a master regulator of mitochondrial biogenesis. Moreover, the mitochondrial biogenesis induced by exposure to cold was markedly reduced in brown adipose tissue of endothelial nitric oxide synthase null-mutant (eNOS-/-) mice, which had a reduced metabolic rate and accelerated weight gain as compared to wild-type mice. Thus, a nitric oxide-cGMP-dependent pathway controls mitochondrial biogenesis and body energy balance. 相似文献
308.