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Mounting evidence has revealed pathological interactions between HIV and malaria in dually infected patients, but the public health implications of the interplay have remained unclear. A transient almost one-log elevation in HIV viral load occurs during febrile malaria episodes; in addition, susceptibility to malaria is enhanced in HIV-infected patients. A mathematical model applied to a setting in Kenya with an adult population of roughly 200,000 estimated that, since 1980, the disease interaction may have been responsible for 8,500 excess HIV infections and 980,000 excess malaria episodes. Co-infection might also have facilitated the geographic expansion of malaria in areas where HIV prevalence is high. Hence, transient and repeated increases in HIV viral load resulting from recurrent co-infection with malaria may be an important factor in promoting the spread of HIV in sub-Saharan Africa.  相似文献   
23.
Cystic thymoma was diagnosed in 14 cats in a period of 6 years. The most common clinical sign was laboured breathing. The tumours were characterized by various-sized cystic spaces with central vessels. The epithelial cells varied from oval to spindle to polygonal cells enclosing cystic spaces or in pure epithelial cell components. The nuclei of the neoplastic cells had scattered chromatin and small nucleoli. The cytoplasm was pale eosinophilic. The concentration of mature lymphocytes varied from area to area with rare germinal centres. Immunohistochemically, the epithelial cells stained only with AE(1)/AE(3). The central vessels were positive for vimentin, smooth muscle actin, and factor VIII antigen. Electron microscopy revealed that the cyst walls were lined by epithelial cells that were joined by desmosomes, and the walls were well separated from the cystic spaces by a well-defined basement membrane. The neoplastic epithelial cells contained scattered tonofilaments. Three of the cats had metastasis to the lymph nodes and lungs. Two novel cases of ectopic cystic thymoma have also been described. Results of this study reveal that cystic thymoma is uncommon in cats, and that the histomorphologic, immunohistochemical, and electron microscopic features are similar to those of cystic thymoma in humans.  相似文献   
24.
In order to accelerate breeding progress of oil-used hemp, 8 quality traits related to lipid component were measured and analyzed in 55 representative hemp germplasms. Results showed that linolenic acid content had the highest variance coefficient of 51.67% as well as protein content had minimum variance coefficient of 4.07%. Correlation analysis showed that total oil content was significantly positively correlated to linolenic acid, while significantly negatively correlated with oleinic acid. Protein content was significantly positively correlated with linolenic acid but significantly negatively with stearic acid. Both total oil and protein content were closely correlated with other traits. The first 3 PCs from principal component analysis of 8 traits accounted for 83.53% contribution. All hemp germplasms were classified into 3 groups at the level of euclidian distance D=8.5 using cluster analysis. The above analysis and classification may provide a reliable theoretical basis and technological guidance for germplasms utilizing and accelerating breeding process.  相似文献   
25.
Dietary acidifiers have been recognized as beneficial in animal production including aquacultural production of fish where they confer such benefits as improved feed utilization, growth, and resistance to bacterial pathogens. If improvements in growth and immune responses by acidifier supplementation can be confirmed in shrimp, then mortalities due to diseases could be minimized, limiting the emergence of disease‐resistant bacterial pathogens as a potential result of antibiotic misuse. With this in mind, a 35‐d feeding trial was conducted to evaluate growth, enteric microbiota populations, and nonspecific immune responses of Litopenaeus vannamei fed diets containing the commercial acidifier Vitoxal, based on acidic calcium sulfate in an indoor temperature‐controlled, recirculating culture system without any natural productivity. Experimental diets were formulated to contain 0 (basal), 0.4, 1.2, 1.6, or 2.0% acidic calcium sulfate (ACS) by weight. Shrimp fed in excess, 15 times a day using automatic feeders. Weight gain and survival among treatments were excellent, but not significantly different (P > 0.05). Denaturing gradient gel electrophoresis analysis revealed that the enteric microbial community of shrimp fed the basal diet differed markedly from those fed the acidifier on the basis of 64.9% similarity coefficient. Shrimp fed the commercial acidifier at 1.2 and 2.0% responded significantly (P < 0.05) better to reduced stress and displayed enhanced immune responses including hemocyte phagocytic capacity, hemolymph protein concentration, hyaline cell counts, and hemolymph glucose, compared with shrimp fed the basal diet. These results point to an enhanced performance in terms of positive shifts in the composition of enteric microbial communities as well as improved immune performance, with no changes in growth or survival.  相似文献   
26.
Monocrotophos (MCP) is one of the organophosphate pesticides extensively used in agriculture and animal husbandry. The present study reports the effects of sub‐lethal concentrations of MCP on gonadosomatic index (GSI), gonadal histology and breeding fitness of the fish Anabas testudineus. The fish were exposed to three sub‐lethal concentrations of monocrotophos (T1: 3.5 mg/L, T2: 5.3 mg/L and T3: 10.6 mg/L) for 45 days with 12 fish (males and females in equal numbers) in each tank, and one group was kept as control (C) without any treatment. GSI decreased in all treatment groups in comparison with control. Significant decrease in fertilization and hatching rate was observed at all concentrations in comparison with control on 15, 30 and 45 days of monocrotophos exposure. The decreased vitellogenesis, disruption of follicular wall and oocyte atresia were observed in all the treated females at 30 and 45 days of exposure. Rupture of seminiferous tubules was noticed in all the treated males irrespective of exposure periods. The results thus indicated that monocrotophos could deleteriously impact the gonadal structure and function in A. testudineus, which could seriously impact the reproductive success of the animal.  相似文献   
27.
Aquaculture International - Lectin protein families are diverse and multi-functional in crustaceans. The carbohydrate-binding domains (CRDs) of lectins recognize the molecular patterns associated...  相似文献   
28.
Locally available low-cost material viz. sand from the Kaliani river of Kanaighat area of Golaghat district Assam, India, was collected. The sand was fractionated and the different fractions were characterized by classical chemical analysis, powder XRD, SEM-EDXA, DTA-TGA, and by FT-IR. The chemical analysis of the size fraction of a 600–850-μm range gave more than 90% silica. This fractionated portion was modified by coating with iron oxide. Coating was carried out on the washed and separated sand by repeated treatment of Fe(NO3)3 at 110 and 600 °C, respectively. From FESEM analysis, formation of iron oxide coating over sand surface is clearly observed. The coated sand was used to remove toxic fluoride ion from the drinking water. Iron oxide-coated sand shows highly improved fluoride removal capacity compared to raw sand. The defluoridation capacity of coated sands rose up to 89% from 7% in uncoated raw sand. The effects of different parameters like adsorbent dose, contact time, temperature, initial fluoride concentration, and pH and the effects of different anions present in water along with arsenic on defluoridation capacity of the material were studied in a batch mode.  相似文献   
29.
A 35‐day feeding trial was conducted to evaluate growth, bacterial populations of the gastrointestinal tract (GIT) and immune responses of Litopenaeus vannamei fed diets containing the commercial prebiotic Previda®. Diets were formulated to contain Previda® at 0, 0.2, 0.5, 1.0 or 1.6 g kg?1 by weight. At the end of the study, differences in weight gain and survival among treatments were not significant (> 0.05), but denaturing gradient gel electrophoresis analysis revealed that the microbial communities in the GIT changed significantly with the inclusion of dietary Previda® at different levels. Previda® was therefore able to selectively modify the microbial communities in the shrimp's GIT. Although individual bacterial species were not identified, enteric populations in shrimp fed the prebiotic at similar levels of inclusion were genetically similar. In addition, shrimp fed Previda® at 1.6 g kg?1 responded significantly (< 0.05) better immunologically with respect to hemocyte phagocytic capacity, haemolymph protein, hyaline cell counts and haemolymph glucose compared with shrimp fed the basal diet. Although shrimp were not exposed to virulent pathogens in this study, the observed upregulation of some of imm‐une responses upon prebiotic supplementation indicates that an improved outcome of such challenges may be anticipated in Previda®‐fed shrimp under commercial conditions.  相似文献   
30.
Scarcity of water and emission of greenhouse gases (GHGs) are the two key environmental issues affecting crop production in India.Reducing the carbon footprint (CF) and water footprint (WF) of crop production can help to mitigate the environmental hazards that stem from GHG emissions and water scarcity.The CFs and WFs of three major cereal crops,rice,wheat,and maize,were estimated for the year 2014 under the environmental conditions in India,based on national statistics and other data sources.To...  相似文献   
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