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31.
A new coccidian species (Protozoa: Apicomplexa: Eimeriidae) is reported from the endangered yellow cardinal Gubernatrix cristata (Vieillot) in southern Brazil. Isospora bocamontensis n. sp. has oöcysts which are subspheroidal, measure 32.1 × 28.9 μm and have a smooth, bilayered wall c.1.5 μm thick. The micropyle and the oöcyst residuum are absent, but a polar granule is sometimes present. Its sporocysts are ellipsoidal and 17.3 × 12.2 μm in size and contain a half-moon-shaped Stieda body, a prominent, homogeneous substieda body; and a sporocyst residuum composed of a compact mass of granules. The sporozoites have one refractile body and a nucleus.  相似文献   
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To better understand the roles of gammadelta T cells in mucosal infection, we utilized Salmonella enterica serovar Typhimurium (Salmonella serovar Typhimurium) infection in cattle as it closely approximates Salmonella serovar Typhimurium-induced enterocolitis in humans. Protein and gene expression in alphabeta and gammadelta T cells derived from lymphatic ducts draining the gut mucosa in Salmonella serovar Typhimurium-infected calves were analyzed. In calves with enterocolitis, general gene expression trends in gammadelta T cells suggested subtle activation and innate response, whereas alphabeta T cells were relatively quiescent following Salmonella serovar Typhimurium infection. An increase in IL-2R alpha expression on gammadelta T cells from infected calves and results from in vitro assays suggested that gammadelta T cells were primed by Salmonella serovar Typhimurium LPS to better respond to IL-2 and IL-15. Together with gene expression trends in vivo, these data support early priming activation of target tissue gammadelta T cells during Salmonella serovar Typhimurium infection.  相似文献   
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We analyzed single nucleotide polymorphisms in calpain, leptin, leptin receptor, and growth hormone receptor genes and their association with color, drip and cooking losses of longissimus muscle at 7, 14 and 21 days postmortem in 638 purebred Nellore bulls slaughtered between 22 and 26 months of age. Meat samples were vacuum-packed and aged at 4°C. The single nucleotide polymorphisms T945M, GHR2, E2FB, and CAPN4751 were evaluated. All genotypic classes were observed; however, the T/T genotype of T945M and E2FB was found at a low frequency. A significant association of E2FB with drip loss (a measure of water-holding capacity) was detected at seven days of meat aging. CAPN4751 had an additive effect on red and yellow color intensities. The T allele of CAPN4751 was found to be positively associated with improved meat color, but not with meat tenderness, differing from a previous report indicating that it is associated with meat tenderness. We conclude that the potential for use of CAPN4751 as a marker for these meat quality traits requires further research.  相似文献   
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Mesenchymal stem cells (MSCs) are viewed as safe, readily available and promising adult stem cells, which are currently used in several clinical trials. Additionally, their soluble-factor secretion and multi-lineage differentiation capacities place MSCs in the forefront of stem cell types with expected near-future clinical applications. In the present work MSCs were isolated from the umbilical cord matrix (Wharton''s jelly) of human umbilical cord samples. The cells were thoroughly characterized and confirmed as bona-fide MSCs, presenting in vitro low generation time, high proliferative and colony-forming unit-fibroblast (CFU-F) capacity, typical MSC immunophenotype and osteogenic, chondrogenic and adipogenic differentiation capacity. The cells were additionally subjected to an oligodendroglial-oriented step-wise differentiation protocol in order to test their neural- and oligodendroglial-like differentiation capacity. The results confirmed the neural-like plasticity of MSCs, and suggested that the cells presented an oligodendroglial-like phenotype throughout the differentiation protocol, in several aspects sharing characteristics common to those of bona-fide oligodendrocyte precursor cells and differentiated oligodendrocytes.  相似文献   
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The Bacteroides genus, the most prevalent anaerobic bacteria of the intestinal tract, carries a plethora of the mobile elements, such as plasmids and conjugative and mobilizable transposons, which are probably responsible for the spreading of resistance genes. Production of β-lactamases is the most important resistance mechanism including cephalosporin resistance to β-lactam agents in species of the Bacteroides fragilis group. In our previous study, the cfxA gene was detected in B. distasonis species, which encodes a clinically significant broad-spectrum β-lactamase responsible for widespread resistance to cefoxitin and other β-lactams. Such gene has been associated with the mobilizable transposon Tn4555. Therefore, the aim of this study was to detect the association between the cfxA gene and the presence of transposon Tn4555 in 53 Bacteroides strains isolated in Rio de Janeiro, Brazil, by PCR assay. The cfxA gene was detected in 11 strains and the Tn4555 in 15. The transposon sequence revealed similarities of approximately 96% with the B. vulgatus sequence which has been deposited in GenBank. Hybridization assay was performed in attempt to detect the cfxA gene in the transposon. It was possible to associate the cfxA gene in 11 of 15 strains that harbored Tn4555. Among such strains, 9 presented the cfxA gene as well as Tn4555, but in 2 strains the cfxA gene was not detected by PCR assay. Our results confirm the involvement of Tn4555 in spreading the cfxA gene in Bacteroides species.  相似文献   
37.
The health of the coral reefs of the Abrolhos Bank (Southwestern Atlantic) was characterized with a holistic approach using measurements of four ecosystem components: (i) inorganic and organic nutrient concentrations, [1] fish biomass, [1] macroalgal and coral cover and (iv) microbial community composition and abundance. The possible benefits of protection from fishing were particularly evaluated by comparing sites with varying levels of protection. Two reefs within the well-enforced no-take area of the National Marine Park of Abrolhos (Parcel dos Abrolhos and California) were compared with two unprotected coastal reefs (Sebasti?o Gomes and Pedra de Leste) and one legally protected but poorly enforced coastal reef (the "paper park" of Timbebas Reef). The fish biomass was lower and the fleshy macroalgal cover was higher in the unprotected reefs compared with the protected areas. The unprotected and protected reefs had similar seawater chemistry. Lower vibrio CFU counts were observed in the fully protected area of California Reef. Metagenome analysis showed that the unprotected reefs had a higher abundance of archaeal and viral sequences and more bacterial pathogens, while the protected reefs had a higher abundance of genes related to photosynthesis. Similar to other reef systems in the world, there was evidence that reductions in the biomass of herbivorous fishes and the consequent increase in macroalgal cover in the Abrolhos Bank may be affecting microbial diversity and abundance. Through the integration of different types of ecological data, the present study showed that protection from fishing may lead to greater reef health. The data presented herein suggest that protected coral reefs have higher microbial diversity, with the most degraded reef (Sebasti?o Gomes) showing a marked reduction in microbial species richness. It is concluded that ecological conditions in unprotected reefs may promote the growth and rapid evolution of opportunistic microbial pathogens.  相似文献   
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Nitrile degradation by Candida guilliermondii CCT 7207 using free and immobilized cell systems was compared. Different specific growth rates were observed for immobilized (mumax=0.021 h(-1)) and the free cells (mumax=0.029 h(-1)). The maximum specific rate of acetic acid formation was 0.387 h(-1) and 0.266 h(-1) for free and immobilized cells, respectively. Cell adhesion to the support materials was confirmed by scanning electron microscopy. When immobilized, the yeast was able to use high nitrile and amide concentrations (aliphatic and aromatic) as nitrogen sources. The results suggest that C. guilliermondii CCT 7207 presents a physiological pattern potentially useful for the bioremediation of polluted environments or for the bioproduction of amides and organic acid of high commercial value.  相似文献   
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