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91.
Bovine tuberculosis (bTB), widely considered a disease of livestock, can also affect large game species despite their poorly understood role in the epidemiology of the endemic state of the disease. The Idanha-a-Nova County, situated in the eastern region of central Portugal, is one of the most important regions for large game hunting activity. In order to investigate the role of large game and the presence of bTB in Idanha-a-Nova, 132 wild boar (Sus scrofa) and 339 red deer (Cervus elaphus) were inspected for bTB-compatible lesions (bTBCL) during the 2008–2009 hunting season. Tissue samples with bTBCL were collected and processed for bacteriological confirmation and spoligotyping of Mycobacterium bovis isolates. In wild boar, bTB lesions were single, mostly calcified (21/29, 72.4%) and situated in the mandibular lymph nodes. Lesions were more severe and largely non-calcified (36/40, 90%) in red deer. Wild boar presented a consistently higher bTB infection rate than the red deer; however, the difference was only significant in the southern B area. This area was significantly affected by bTB for both animal species (up to 72.7% in wild boar and 34.8% in red deer) and requires the urgent implementation of intervention measures to contain the disease. Wild boar may assume an important role in the emergence of new disease foci in distant areas that infected red deer cannot reach. Spoligotyping of M. bovis isolates grouped the strains into three clusters, revealing patterns common to wild boar, red deer, and also to local cattle, indicating possible transmission among different animal species.  相似文献   
92.
A new species of Hypostomus with spoon-shaped teeth is described from the Rio Cupari basin, a right margin affluent of the lower Rio Tapajós, Pará State, Brazil. The new species inhabits rocky bottom areas in the main channel of Rio Cupari and its tributaries. The new species can be distinguished from all its congeners, except from the Hypostomus cochliodon group, by having six to eight spoon-shaped teeth, dentaries angled at less than 80° and the absence of a notch between the hyomandibular and the metapterygoid. The new species is distinguished from all species of the H. cochliodon group by its unique colour pattern, containing dark vermiculations on head and anterior portion of the trunk, and by the absence of medial buccal papillae.  相似文献   
93.
94.
A conformational analysis of the fragment 110–121 of VP3 coating protein of the hepatitis A virus was carried out using circular dichroism spectroscopy and computational studies. The latter studies indicate the tendency of the peptide to adopt hairpin-type structures. Circular dichroism experiments indicate that, in spite of the fact that the isolated peptide exhibits no structure under different experimental conditions, negatively charged liposomes induce a secondary structure that agrees with the results of the computational study.  相似文献   
95.
96.
Localized expression of genes in plants from T‐DNAs delivered into plant cells by Agrobacterium tumefaciens is an important tool in plant research. The technique, known as agroinfiltration, provides fast, efficient ways to transiently express or silence a desired gene without resorting to the time‐consuming, challenging stable transformation of the host, the use of less efficient means of delivery, such as bombardment, or the use of viral vectors, which multiply and spread within the host causing physiological alterations themselves. A drawback of the agroinfiltration technique is its temperature dependence: early studies have shown that temperatures above 29 °C are nonpermissive to tumour induction by the bacterium as a result of failure in pilus formation. However, research in plant sciences is interested in studying processes at these temperatures, above the 25 °C experimental standard, common to many host–environment and host–pathogen interactions in nature, and agroinfiltration is an excellent tool for this purpose. Here, we measured the efficiency of agroinfiltration for the expression of reporter genes in plants from T‐DNAs at the nonpermissive temperature of 30 °C, either transiently or as part of viral amplicons, and envisaged procedures that allow and optimize its use for gene expression at this temperature. We applied this technical advance to assess the performance at 30 °C of two viral suppressors of silencing in agropatch assays [Potato virus Y helper component proteinase (HCPro) and Cucumber mosaic virus 2b protein] and, within the context of infection by a Potato virus X (PVX) vector, also assessed indirectly their effect on the overall response of the host Nicotiana benthamiana to the virus.  相似文献   
97.

Background

Since osteoporosis is a complex disease characterized by low bone mineral density (BMD), which is determined by an interaction of genetics with metabolic and environmental factors, the aim of this study was to analyze the possible association among one polymorphism of VDR and two polymorphisms of ESR1; as well as their haplotypes with BMD in postmenopausal Mexican-mestizo women.

Methods

We studied 742 postmenopausal Mexican-mestizo women. A structured questionnaire for risk factors was applied and BMD was measured in the lumbar spine and total hip by dual-energy X-ray absorptiometry. DNA was obtained from blood leukocytes. One polymorphism of VDR (rs11568820) and two of ESR1 (rs2234693 and rs9340799) were studied. Real-time PCR allelic discrimination was used for genotyping. The differences between the means of the BMDs according to genotype were analyzed with covariance. Hardy–Weinberg equilibrium was tested. Pairwise linkage disequilibrium between single nucleotide polymorphisms was calculated by direct correlation r2; haplotype analysis was conducted.

Results

Rs9340799 of ESR1 and one haplotype formed by the two polymorphisms of the ESR1 were significantly associated with FN-BMD variations. Moreover, analysis of the genotype of rs11568820 of VDR and the rs2234693 of ESR1 showed no significant differences with BMD variations.

Conclusions

Our results showed that rs9340799 and one haplotype of ESR1 were significantly associated with BMD only at the femoral neck and this association remained after adjusting for covariates.  相似文献   
98.
ObjectivePonseti method is suitable to treat neglected clubfoot after the walking age. However, limited evidence exists on its effectiveness, outcomes and rate of relapse. Methods: 429 clubfeet in 303 patients with no previous treatment and older than one-year were treated with the Ponseti method in 15 centers from seven countries. The median age at treatment onset was three years, and the median follow-up of 1.3 years. Standard Ponseti Method was applied. Bilateral abduction brace was recommended after casting. Patients were classified according to group ages (<2 years, 2-4 years, >4-8years, >8 years). Feet were evaluated by Pirani score and a clinical outcome classification. Relapses were described in a subset of 103 clubfeet with minimal follow-up of two years.ResultsPonseti method was able to correct the deformity in 87% (373 of 429) of neglected clubfeet, after a mean of 6.8 casts. Residual equinus was treated with percutaneous sectioning of the Achilles tendon in 356 (83%) of 429 clubfeet. A bilateral foot abduction brace was prescribed and used in 70% of children. Relapses occurred in 31% (32 of 103) of clubfeet and were associated with age less than 4 years at treatment onset, and bracing noncompliance.ConclusionThe Ponseti method is effective to correct neglected clubfeet. Relapses occurred in one-third of clubfeet, mainly in children younger than four years and in noncompliance with the brace. Our study reinforces the recommendation for the Ponseti method with no major modification to treat neglected clubfoot in patients after walking age.Level of Evidence: IV  相似文献   
99.
The synthesis of glycogen in bacteria and starch in plants is allosterically controlled by the production of ADP-glucose by ADP-glucose pyrophosphorylase. Using computational studies, site-directed mutagenesis, and kinetic characterization, we found a critical region for transmitting the allosteric signal in the Escherichia coli ADP-glucose pyrophosphorylase. Molecular dynamics simulations and structural comparisons with other ADP-glucose pyrophosphorylases provided information to hypothesize that a Pro103–Arg115 loop is part of an activation path. It had strongly correlated movements with regions of the enzyme associated with regulation and ATP binding, and a network analysis showed that the optimal network pathways linking ATP and the activator binding Lys39 mainly involved residues of this loop. This hypothesis was biochemically tested by mutagenesis. We found that several alanine mutants of the Pro103–Arg115 loop had altered activation profiles for fructose-1,6-bisphosphate. Mutants P103A, Q106A, R107A, W113A, Y114A, and R115A had the most altered kinetic profiles, primarily characterized by a lack of response to fructose-1,6-bisphosphate. This loop is a distinct insertional element present only in allosterically regulated sugar nucleotide pyrophosphorylases that could have been acquired to build a triggering mechanism to link proto-allosteric and catalytic sites.  相似文献   
100.

Background

Statins are commonly used against arteriosclerotic disease, but recent retrospective analyses have suggested that statins also prevent cancer. The aim of this systematic review is to verify the vitro anti-tumor effects of statins on head and neck squamous cell carcinoma.

Methods

Studies were gathered by searching Cochrane, MEDLINE, EMBASE, LILACS, and PubMed, up until May 9, 2015, with no time or language restrictions. Only in vitro studies that discuss the effect of statins on head and neck carcinoma were selected.

Results

Of 153 identified papers, 14 studies met the inclusion criteria. These studies demonstrated that statins had a significant effect on head and neck squamous cell carcinoma cell lines and influenced cell viability, cell cycle, cell death, and protein expression levels involved in pathways of carcinogenesis, which corroborates with the potential in vitro anti-tumor effects. It provides highlights about the biological mechanisms of statins used alone or associated with traditional therapy for cancer.

Conclusions

Though there are few studies on the topic, currently available evidence suggests that statins shows that preclinical experiments supports the potentiality of statin as an adjuvant agent in chemotherapy and/or radiotherapy approaches routinely used in the management of HNSCC and should undergo further clinical assessment.  相似文献   
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