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51.
Habitat loss is the main threat to biodiversity conservation worldwide. Some species may be particularly susceptible to the effects of fragmentation and the isolation of populations. The impacts of human activity on wild animal populations may be understood through relationships between individual genetic data and spatial landscape variables, particularly when considering local population dynamics influenced by fragmented habitats. Thus, the objective of this study was to analyze the population structure and genetic diversity of the giant anteater (Myrmecophaga tridactyla) using an individual sampling scheme (ISS) on a regional geographic scale. Data were collected from 41 specimens from twenty different locations in São Paulo State, Brazil, and six polymorphic microsatellite loci were genotyped. Our results indicate that barriers to gene flow exist and have segregated individuals of the farther away areas into two spatially structured clusters. The populations were also found to have high genetic diversity. The experimental sampling approach used herein enabled an analysis of the population dynamics of the giant anteater on a regional scale, as well as the identification of priority populations for genetic resource conservation for this species. The results reflect the need for adequate management plans. The efficacy of the sampling scheme may vary based on the study model used, but we argue that the use of an ISS combined with suitable molecular markers and statistical methods may serve as an important tool for initial analyses of threatened or vulnerable species, particularly in anthropized regions where populations are small or hard to characterize.  相似文献   
52.
Ferraris L  Aires J  Butel MJ 《Anaerobe》2012,18(1):172-173
Robinsoniella peoriensis is a recently described anaerobic, spore-forming, Gram positive bacillus originally recovered from swine-manure and clinical human samples. In this study, R. peoriensis was isolated from the feces of one set of twin premature neonates. It suggests that this anaerobic bacillus may be a commensal bacterium of human gut.  相似文献   
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54.
The invasive gall wasp Quadrastichus erythrinae, a pest of Erythrina plants, is recorded for the first time in South America in Espírito Santo, Brazil. Research on Q. erythrinae and its potential natural enemies in this region is required to determine the need for classical biological control of this invasive pest.  相似文献   
55.
BackgroundLung cancer is the most common cancer worldwide. It is estimated that 60% of patients with NSCLC at time of diagnosis have advanced disease. The aim of this study was to identify factors that play a major role in the survival of lung cancer patients treated with palliative radiotherapy.Materials and methodsWe retrospectively reviewed data of 280 lung cancer patients treated with palliative radiotherapy from January 2013 to December 2017. A multivariate analysis using the proportional hazards model of Cox was conducted. Also, Kaplan Meier curves were used to describe the distribution of survival times of the patients. The level of significance was set at 0.05.ResultsThe mean age at diagnosis was 65.6 years. About 77.5% of patients were male and 22.5% were female. In our cohort > 95% had stage 4 lung cancer. Most cases were adenocarcinomas (72.5%) and ECOG-PS 0–1 (80.4%). Different sites were submitted to palliative treatment: 120 brain metastases, 96 bone metastases, 53 lung tumour, 8 lymph nodes and 3 lung metastases. Brain as first site of palliative radiotherapy (HR: 1.553, 95% CI: 1.167–2.067, p = 0.003) and ECOG-PS 2–3 compared with ECOG-PS 0–1 (HR: 2.253, 95% CI: 1.546–3.283, p ≤ 0.001) were associated with increased likelihood of lung cancer death. Patients who received biological therapy had 70.7% (p ≤ 0.001) reduction in lung cancer death risk.ConclusionBrain as the first metastatic site treated with radiotherapy and ECOG-PS 2–3 are associated with increased lung cancer death. Biological therapy was associated with decreased death risk.  相似文献   
56.
The International Journal of Life Cycle Assessment - Aquaculture is the best alternative to fulfil global fish demand, however it still relies heavily on fisheries-derived products for aquafeeds...  相似文献   
57.
The hypothesis whether valproic acid (VPA) and its main microsomal metabolite, Delta(4)-valproic acid, can be activated to the respective CoA esters in the cell cytosol was investigated. The valproyl-CoA formation was measured in different subcellular fractions obtained by differential centrifugation of liver homogenates of rats treated with VPA (studies ex vivo) and digitonin fractionation of rat hepatocytes incubated with VPA and cofactors (studies in vitro). The results show that VPA activation may occur in the cytosol and is not restricted to the mitochondrial matrix as believed until now. Furthermore, the activation of Delta(4)-VPA is demonstrated in vitro. Valproyl-CoA and Delta(4)-valproyl-CoA were detected after in vitro incubations and the former also in the mitochondrial and cytosolic fractions obtained from liver cells of treated rats. The activation to valproyl-CoA was characterized in cytosolic fractions, optimized with respect to time and protein and the kinetic constants (K(m)(app)) were estimated for the reaction substrates. Other medium-chain fatty acids decreased the formation of valproyl-CoA suggesting a competition for both mitochondrial and extra-mitochondrial VPA activating enzymes. The present findings suggest additional mechanisms of mitochondrial dysfunction associated with VPA, and they may contribute to the further understanding of the toxic effects associated with this drug.  相似文献   
58.
Infections with human papillomavirus type 16 (HPV-16) are closely associated with the development of human cervical carcinoma, which is one of the most common causes of cancer death in women worldwide. At present, the most promising vaccine against HPV-16 infection is based on the L1 major capsid protein, which self-assembles in virus-like particles (VLPs). In this work, we used a lactose-inducible system based on the Lactobacillus casei lactose operon promoter (plac) for expression of the HPV-16 L1 protein in L. casei. Expression was confirmed by Western blotting, and an electron microscopy analysis of L. casei expressing L1 showed that the protein was able to self-assemble into VLPs intracellularly. The presence of conformational epitopes on the L. casei-produced VLPs was confirmed by immunofluorescence using the anti-HPV-16 VLP conformational antibody H16.V5. Moreover, sera from mice that were subcutaneously immunized with L. casei expressing L1 reacted with Spodoptera frugiperda-produced HPV-16 L1 VLPs, as determined by an enzyme-linked immunosorbent assay. The production of L1 VLPs by Lactobacillus opens the possibility for development of new live mucosal prophylactic vaccines.  相似文献   
59.
Mucosal epithelia constitute the first barriers to be overcome by pathogens during infection. The induction of protective IgA in this location is important for the prevention of infection and can be achieved through different mucosal immunization strategies. Lactic acid bacteria have been tested in the last few years as live vectors for the delivery of antigens at mucosal sites, with promising results. In this work, Streptococcus pneumoniae PsaA antigen was expressed in different species of lactic acid bacteria, such as Lactococcus lactis, Lactobacillus casei, Lactobacillus plantarum, and Lactobacillus helveticus. After nasal inoculation of C57Bl/6 mice, their ability to induce both systemic (IgG in serum) and mucosal (IgA in saliva, nasal and bronchial washes) anti-PsaA antibodies was determined. Immunization with L. lactis MG1363 induced very low levels of IgA and IgG, possibly by the low amount of PsaA expressed in this strain and its short persistence in the nasal mucosa. All three lactobacilli persisted in the nasal mucosa for 3 days and produced a similar amount of PsaA protein (150-250 ng per 10(9) CFU). However, L. plantarum NCDO1193 and L. helveticus ATCC15009 elicited the highest antibody response (IgA and IgG). Vaccination with recombinant lactobacilli but not with recombinant L. lactis led to a decrease in S. pneumoniae recovery from nasal mucosa upon a colonization challenge. Our results confirm that certain Lactobacillus strains have intrinsic properties that make them suitable candidates for mucosal vaccination experiments.  相似文献   
60.
MICs of tetracyclines were determined for 86 human Bifidobacterium isolates and three environmental strains. The tet(O) gene was found to be absent in these isolates. tet(W) and tet(M) were found in 26 and 7%, respectively, of the Bifidobacterium isolates, and one isolate contained both genes. Chromosomal DNA hybridization showed that there was one chromosomal copy of tet(W) and/or tet(M).  相似文献   
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