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Marcelino I de Almeida AM Brito C Meyer DF Barreto M Sheikboudou C Franco CF Martinez D Lefrançois T Vachiéry N Carrondo MJ Coelho AV Alves PM 《Veterinary microbiology》2012,156(3-4):305-314
The Rickettsiales Ehrlichia ruminantium (ER) is the causative agent of heartwater, a fatal tick-borne disease of livestock in sub-Saharan Africa and in the Caribbean, posing strong economical constraints to livestock production. In an attempt to identify the most prominent proteins expressed by this bacterium, especially those encoded by the major antigenic protein 1 (map1) multigene family, a proteome map of ER cultivated in endothelial cells was constructed by using two dimensional gel electrophoresis combined with mass spectrometry. Among the sixty-four spots detected, we could identify only four proteins from the MAP1-family; the other proteins detected were mainly related to energy, amino acid and general metabolism (26%), to protein turnover, chaperones and survival (21%) and to information processes (14%) or classified as hypothetical proteins (23%). Additional studies on MAP1-family protein using immunochemical labeling also revealed that these proteins are differentially expressed along the bacterium life cycle, presenting different structural organization. Interestingly, when infectious elementary bodies (EBs) are released from host cells, MAP1 appears to be organized in SDS and heat-resistant dimers and trimers stabilized by disulfide bridges. Overall, the results presented herein not only reveal the first partial proteome map of ER but provide new insights on the expression ER MAP1-family proteins in host endothelial cells. 相似文献
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António Santos Ofélia Anjos Maria Emília Amaral Nuno Gil Helena Pereira Rogério Sim?es 《Journal of Wood Science》2012,58(6):479-486
Wood density and pulp yield are key parameters in the evaluation of tree productivity and quality for pulping and their relationships are of high practical importance. The influence of wood density on pulp yield and other pulp quality parameters was investigated using Acacia melanoxylon and its natural variability as a case study. Twenty trees were harvested (five trees in each of four sites in Portugal), and wood discs taken at different height levels, from the base to the top of the tree, providing 100 wood samples, covering the natural variability of wood density ranging from 449?kg?m?3 to 649?kg?m?3. Under the same experimental conditions of kraft pulping, screened pulp yield ranged 47.0?C58.2?%, Kappa number 10.9?C18.4, ISO brightness 14.9?C45.6, fibre length 0.660?C0.940?mm and fibre width 16.2?C22.9???m. The pulp yield and Kappa number were not correlated with wood density. Higher pulp yields were associated with lower Kappa numbers and alkali consumption, suggesting the important role of chemical composition of wood on kraft cooking. The results confirm the high pulping potential of Acacia melanoxylon trees grown in Portugal and suggest the possibility of tree selection using both wood density and pulp yield. 相似文献
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Diaz S Fonseca IP Rodrigues A Martins C Cartaxeiro C Silva MJ Brito TV Alexandre-Pires G Santos-Gomes GM 《Veterinary parasitology》2012,189(2-4):137-144
Canine leishmaniosis, caused by Leishmania infantum, is a systemic disease with variable clinical signs and a progressive evolution. This disease is characterized by impaired T cell-mediated immune response, which has been associated with disease chronicity and high mortality. Protective immunity against leishmaniosis is thought to be mediated by T cell and cytokine production. The T cell activation requires a primary signal delivered by the major histocompatibility complex (MHC) molecules present on the surface of antigen presenting cells, and a non-specific signal generated by co-stimulatory molecules. To characterize canine immune responses in the presence of L. infantum parasites or their antigens, in vitro cell cultures of canine macrophages and lymphocytes were established, and the macrophages presenting MHC class II molecules were evaluated as well as the expression of IL-12 and CD80-86 co-stimulatory molecules and nitric oxide production. The results showed for the first time the up-regulation of MHC class II molecules on the surface in canine peripheral blood monocyte-derived macrophages during L. infantum infection in the presence of lymphocytes. In addition, a lack of co-stimulatory expression and a reduced release of nitric oxide were observed, suggesting a loss of T cell function and consequently an inactivation of the macrophage oxidative burst which, in turn, favors the survival of Leishmania. These results constitute a new contribution for the understanding of the interactions between L. infantum and the canine immune system. 相似文献
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Leonardo José Assis de Barros Marcelo de Andrade Ferreira Julio César Vieira de Oliveira Djalma Cordeiro dos Santos Juana Catarina Cariri Chagas Adryanne Marjorie Souza Vitor Alves Aghata Elins Moreira da Silva Wandemberg Rocha Freitas 《Tropical animal health and production》2018,50(1):149-154
This study aims to evaluate the effect of the Tifton 85 hay (Cynodon dactylon L. Pers) replacement by Orelha de Elefante Mexicana spineless cactus (Opuntia stricta [Haw.] Haw) on the nutrient intake and digestibility, growth performance, microbial protein synthesis, and efficiency of dietary nitrogen compound utilization in the diets of Girolando heifers. Twenty-four (3.5 months and 100 kg ± 3.5 kg) Girolando heifers (5/8 Holstein x Gyr) were used and arranged in a completely randomized design. Dry matter, organic matter, crude protein, and neutral detergent fiber decreased linearly as a function of the levels of Tifton hay (TH) replacement by Orelha de Elefante Mexicana spineless cactus (OEM). The non-fiber carbohydrate intake and coefficient of dry matter digestibility increased, while the neutral detergent fiber (NDF) digestibility decreased linearly with the OEM inclusion. After evaluating the growth performance by observing weight gain and morphometric measurements, there were no significant alterations. The urinary volume, nitrogen balance as well as the efficiency of nitrogen retention had increased, while the urinary and plasma urea concentrations had decreased linearly with the OEM inclusion. The results obtained in this study show that Orelha de Elefante Mexicana spineless cactus should replace Tifton hay in post-weaned heifer diets. 相似文献
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Helena M. Amaro Rita Barros Tnia Tavares Raquel Almeida Isabel Sousa Pinto Francisco Xavier Malcata Ana Catarina Guedes 《Marine drugs》2021,19(11)
Bioactive lipidic compounds of microalgae, such as polyunsaturated fatty acids (PUFA) and carotenoids, can avoid or treat oxidation-associated conditions and diseases like inflammation or cancer. This study aimed to assess the bioactive potential of lipidic extracts obtained from Gloeothece sp.–using Generally Recognized as Safe (GRAS) solvents like ethanol, acetone, hexane:isopropanol (3:2) (HI) and ethyl lactate. The bioactive potential of extracts was assessed in terms of antioxidant (ABTS•+, DPPH•, •NO and O2•assays), anti-inflammatory (HRBC membrane stabilization and Cox-2 screening assay), and antitumor capacity (death by TUNEL, and anti-proliferative by BrdU incorporation assay in AGS cancer cells); while its composition was characterized in terms of carotenoids and fatty acids, by HPLC-DAD and GC-FID methods, respectively. Results revealed a chemopreventive potential of the HI extract owing to its ability to: (I) scavenge -NO• radical (IC50, 1258 ± 0.353 µg·mL−1); (II) inhibit 50% of COX-2 expression at 130.2 ± 7.4 µg·mL−1; (III) protect 61.6 ± 9.2% of lysosomes from heat damage, and (IV) induce AGS cell death by 4.2-fold and avoid its proliferation up to 40% in a concentration of 23.2 ± 1.9 µg·mL−1. Hence, Gloeothece sp. extracts, namely HI, were revealed to have the potential to be used for nutraceutical purposes. 相似文献
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Cortisol and testosterone accumulation in a low pH recirculating aquaculture system for rainbow trout (Oncorhynchus mykiss) 
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下载免费PDF全文 Vasco C Mota Catarina I M Martins Ep H Eding Adelino V M Canário Johan A J Verreth 《Aquaculture Research》2017,48(7):3579-3588
Steroids accumulate in recirculating aquaculture system (RAS), although explanatory factors for such accumulation are still poorly explored. This study investigated the effect of water exchange rate and pH in six replicated RAS on the concentration of the stress hormone cortisol in rainbow trout blood plasma and in the holding water and of the sex steroids testosterone, 11‐ketotestosterone (11‐KT) and 17,20β‐dihydroxypregn‐4‐en‐3‐one (17,20β‐P) over a 70‐day experimental period. Three combinations of water exchange rate and pH were used each treatment, with two replications: (i) high water exchange rate (±1700 L kg?1 feed) and neutral pH (±7.3), (ii) low water exchange rate (±500 L kg?1 feed) and neutral pH (±7.3) and (iii) low water exchange rate (±500 L kg?1 feed) and low pH (±5.8). Plasma cortisol concentrations at day 70 were higher (24.4 ± 9.5 ng mL?1) for fish kept at low pH when compared to fish kept at neutral pH (12.0 ± 0.1 and 8.7 ± 0.2 ng mL?1). Water cortisol and testosterone concentrations at day 35 were higher at low pH than at neutral pH, whereas water 11‐KT and 17,20β‐P did not differ among treatments. At day 70, there were no significant differences between low and high pH. These results demonstrate that low pH contributes to increased plasma cortisol concentrations and to its accumulation in water, possibly indicating a stress response to low pH. The higher concentration of testosterone but not of the other sex hormones point to unspecified reproductive effects that need further investigation. 相似文献
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Marco Antonio Thomaz Antonio Cleber da Silva Camargo Bruno Leite dos Anjos Carlos Frederico Ceccon Lanes 《Aquaculture Research》2019,50(6):1651-1657
Tuviras (Gymnotus sp.) are a small fish widely used as live bait in sport fishing. Interest in its culture has increased, but there are still several bottlenecks that need to be solved. For example, the process of sexing in tuviras is difficult since they do not present sexual dimorphism. Thus, the aim of this study was to verify if an abdominal puncture could be used as an inexpensive, fast and reliable technique to identify the sex of adult Gymnotus sp. Before performing the abdominal puncture, five individuals were dissected to determine the exact location of the gonads. Based on this information, the abdominal puncture was performed 6 cm away from the tip of the animal's head and 1 cm below the lateral line with an intravenous infusion set connected to a 5 ml syringe. An abdominal puncture was performed on 24 adult animals that were larger than 20 cm in length. Twenty‐two individuals were sexed correctly, and the accuracy degree was 91.66%. The survival rate of the animals 96 hr after the abdominal puncture was 100%. These results indicate that the abdominal puncture is an easy, simple, fast and inexpensive technique that can be performed in a reliable way. 相似文献
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Tonoli Adonis Lopes dos Anjos Breno Benvindo Belan Leônidas Leoni de Resende Camara Guilherme Silva e Castro Leonardo Humberto Pereira Jéssica Priscila Cavatte Paulo Cezar da Silva Xavier André Moraes Willian Bucker 《植物病害和植物保护杂志》2021,128(1):273-278
Journal of Plant Diseases and Protection - White mold caused by the fungus Sclerotinia sclerotiorum is one of the main common bean diseases. The aim of this study was to evaluate the effect of... 相似文献