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151.
Salome Dürr Borna Müller Silvia Alonso Jan Hattendorf Cláudio J. M. Laisse Paul D. van Helden Jakob Zinsstag 《PLoS neglected tropical diseases》2013,7(8)
Tuberculosis (TB) is one of the most devastating infectious diseases worldwide. Whilst global burden estimates for M. tuberculosis infection (MtTB) are well established, accurate data on the contribution of zoonotic TB (zTB) caused by M. bovis or M. caprae to human TB are scarce. The association of M. bovis infection with extrapulmonary tuberculosis has been suggested repeatedly, though there is little scientific evidence available to support this relationship. The present study aimed to determine globally the occurrence of extrapulmonary TB and the primary site (i.e. primary body location affected) of zTB in comparison with MtTB, based on previously published reports. A systematic literature review was conducted in 32 different bibliographic databases, selecting reports on zTB written in English, French, German, Spanish or Portuguese. Data from 27 reports from Africa, America, Europe and the Western Pacific Region were extracted for analyses. Low income countries, in Africa and South-East Asia, were highly underrepresented in the dataset. The median proportion of extrapulmonary TB cases was significantly increased among zTB in comparison with data from registries of Europe and USA, reporting mainly MtTB cases (47% versus 22% in Europe, 73% versus 30% in the USA). These findings were confirmed by analyses of eight studies reporting on the proportions of extrapulmonary TB in comparable populations of zTB and MtTB cases (median 63% versus 22%). Also, disparities of primary sites of extrapulmonary TB between zTB and MtTB were detected. Our findings, based on global data, confirm the widely suggested association between zTB and extrapulmonary disease. Different disability weights for zTB and MtTB should be considered and we recommend separate burden estimates for the two diseases. 相似文献
152.
153.
Forecasting the influence of climatic changes on the distribution of the Maned Wolf (Chrysocyon brachyurus) is important for the conservation of the species. We explored the environmental characteristics than best explain the current distribution of the species, modelled the past and present distribution, projected the niche model into the future, and identified suitable areas for conservation. Niche modelling was performed using Maxent and 21 environmental variables. For past conditions, we considered the Last Glacial Maximum (LGM) and the mid-Holocene (MH) climates. For future conditions, we used the A2a greenhouse gas emission scenario for 2050. Four General Circulation Models (FGOALS 1.0, HADCM3, IPSL-CM4 and MIROC 3.2) were used. The resulting niche model (AUC = 0.89 ± 0.02) predicts maximum probability of presence at precipitation of 106 mm during the coldest quarter, of 396 mm during the warmest quarter, and in totally flat areas. The suitable area for the Maned Wolf currently covers 4,320,364 km2. For the LGM, there were inter-model differences in predicted areas (from 819,324 km2 to 6,395,886 km2) and in geographic location. The MH models showed drastic changes with respect to the present and considerable inter-model variation. Predictions for 2050 show significant (at least 33%) reductions in distribution. Only a minor fraction (39%) of the current distribution can be considered stable for the period LGM-2050. The FGOALS model was the best option for projecting species occurrence into the future because it included the three localities known for the Maned Wolf from the late Pleistocene and predicts stable areas that coincide with spatial patterns of genetic diversity. The FGOALS projection for 2050 predicts a 33% reduction in suitable habitats, indicating some stable areas (central South America) that will probably be key sites for the conservation of the species. 相似文献
154.
Maria A. Herreros Antonio Gonzalez-Bulnes Silvia Iñigo-Nuñez Ignacio Contreras-Solis Jose M. Ros Teresa Encinas 《Reproductive biology》2013,13(1):66-74
The aim of the present study was to determine the toxicokinetics of short-term exposures to di(2-ethylhexyl) phthalate (DEHP) and its effects on ovarian cyclicity and luteal function using a sheep experimental model. For establishing the model, we examined the clearance of DEHP after intravenous (i.v.) and intramuscular (i.m.) administration of a single dose of 25 mg/kg body weight (b.w.) and after i.m. administration of two different doses (25 and 50 mg/kg b.w.; DEHP25 and DEHP50, respectively) three times a week for two months. Results showed a significant, dose-dependent effect of DEHP administration, when compared to the control group (CTL; untreated ewes; n = 6), on the duration of the ewes’ estrous cycles (17.1 ± 0.5 days, CTL; 15.1 ± 0.9 days, DEHP25; 12.0 ± 0.8 days, DEHP50; p < 0.05); 94.9% of the cycles were of regular duration (15–19 days) in CTL, but only 51.1% and 25.4% in DEHP25 and DEHP50, respectively. Corpora lutea (CL) were smaller in DEHP50 than in DEHP25 (p < 0.05) and were smaller in both groups than in CTL (p < 0.005), but the maximum plasma concentrations of progesterone were greater (p < 0.05) in DEHP25 and DEHP50 than in CTL. In conclusion, the exposure of cycling ewes to DEHP causes shortening of the ovulatory cycles due mainly to a reduction in the size and lifespan of CL. However, the exposure to the phthalate is also associated with an increase in circulating concentrations of progesterone, suggesting the influence of DEHP on steroid metabolism. 相似文献
155.
Pascal Vittoz Daniel Cherix Yves Gonseth Verena Lubini Ramona Maggini Niklaus Zbinden Silvia Zumbach 《Journal for Nature Conservation》2013,21(3):154-162
A noticeable increase in mean temperature has already been observed in Switzerland and summer temperatures up to 4.8 K warmer are expected by 2090. This article reviews the observed impacts of climate change on biodiversity and considers some perspectives for the future at the national level.The following impacts are already evident for all considered taxonomic groups: elevation shifts of distribution towards mountain summits, spread of thermophilous species, colonisation by new species from warmer areas and phenological shifts. Additionally, in the driest areas, increasing droughts are affecting tree survival and fish species are suffering from warm temperatures in lowland regions. These observations are coherent with model projections, and future changes will probably follow the current trends.These changes will likely cause extinctions for alpine species (competition, loss of habitat) and lowland species (temperature or drought stress). In the very urbanised Swiss landscape, the high fragmentation of the natural ecosystems will hinder the dispersal of many species towards mountains. Moreover, disruptions in species interactions caused by individual migration rates or phenological shifts are likely to have consequences for biodiversity. Conversely, the inertia of the ecosystems (species longevity, restricted dispersal) and the local persistence of populations will probably result in lower extinction rates than expected with some models, at least in 21st century. It is thus very difficult to estimate the impact of climate change in terms of species extinctions. A greater recognition by society of the intrinsic value of biodiversity and of its importance for our existence will be essential to put in place effective mitigation measures and to safeguard a maximum number of native species. 相似文献
156.
Mariarosaria Calvello Silvia Tabano Patrizia Colapietro Silvia Maitz Alessandra Pansa Claudia Augello Faustina Lalatta Barbara Gentilin Filippo Spreafico Luciano Calzari Daniela Perotti Lidia Larizza Silvia Russo Angelo Selicorni Silvia M Sirchia Monica Miozzo 《Epigenetics》2013,8(10):1053-1060
Beckwith-Wiedemann syndrome (BWS) is a rare disorder characterized by overgrowth and predisposition to embryonal tumors. BWS is caused by various epigenetic and/or genetic alterations that dysregulate the imprinted genes on chromosome region 11p15.5. Molecular analysis is required to reinforce the clinical diagnosis of BWS and to identify BWS patients with cancer susceptibility. This is particularly crucial prenatally because most signs of BWS cannot be recognized in utero. We established a reliable molecular assay by pyrosequencing to quantitatively evaluate the methylation profiles of ICR1 and ICR2. We explored epigenotype-phenotype correlations in 19 patients that fulfilled the clinical diagnostic criteria for BWS, 22 patients with suspected BWS, and three fetuses with omphalocele. Abnormal methylation was observed in one prenatal case and 19 postnatal cases, including seven suspected BWS. Seven cases showed ICR1 hypermethylation, five cases showed ICR2 hypomethylation, and eight cases showed abnormal methylation of ICR1 and ICR2 indicating paternal uniparental disomy (UPD). More cases of ICR1 alterations and UPD were found than expected. This is likely due to the sensitivity of this approach, which can detect slight deviations in methylation from normal levels. There was a significant correlation (p < 0.001) between the percentage of ICR1 methylation and BWS features: severe hypermethylation (range: 75–86%) was associated with macroglossia, macrosomia, and visceromegaly, whereas mild hypermethylation (range: 55–59%) was associated with umbilical hernia and diastasis recti. Evaluation of ICR1 and ICR2 methylation by pyrosequencing in BWS can improve epigenotype-phenotype correlations, detection of methylation alterations in suspected cases, and identification of UPD. 相似文献
157.
Central giant cell lesion of the jaws: study of CCND1 gene amplification and p16INK4a protein levels
Renato Luiz Maia Nogueira Mário Henrique Girão Faria Rafael Lima Verde Osterne Roberta Barroso Cavalcante Ronaldo Albuquerque Ribeiro Cassiano Francisco Weege Nonaka Silvia Helena Barem Rabenhorst 《Journal of molecular histology》2013,44(5):527-534
Central giant cell lesions (CGCLs) are uncommon benign jaw lesions with uncertain etiology and a variable clinical behavior. In neoplasms, alterations in molecules involved in the G1/S checkpoint are frequently found. Loss of p16INK4a expression or overexpression of cyclin D1 may stimulate cell proliferation. The purpose of this study was to analyze CCND1 gene amplification and the expression of p16INK4a in CGCLs. Structural analysis of the CCND1 was performed using chromogenic in situ hybridization. Immmunohistochemistry was used to identify p16INK4a protein levels. Statistical analysis correlated the two biomarkers with clinical behavior and between each other. Twenty-four lesions were included, being 11 aggressive and 13 non-aggressive. Moderate/high-level CCND1 amplification was found in 12 lesions. Also, immunoreactivity for p16INK4a was present in 12 cases, mainly in mononuclear cells. There was a significantly higher level of p16INK4a expression in mononuclear cells of non-aggressive lesions and lesions with moderate/high-level CCND1 amplification in mononuclear cells. It could be speculated that some CGCLs may develop as a true benign neoplasm. The higher expression of p16INK4a in non-aggressive lesions and in cases with moderate/high-level CCND1 amplification may show that these molecules have a role in CGCLs. 相似文献
158.
Claudine Porta Abhay Kotecha Alison Burman Terry Jackson Jingshan Ren Silvia Loureiro Ian M. Jones Elizabeth E. Fry David I. Stuart Bryan Charleston 《PLoS pathogens》2013,9(3)
Foot-and-mouth disease remains a major plague of livestock and outbreaks are often economically catastrophic. Current inactivated virus vaccines require expensive high containment facilities for their production and maintenance of a cold-chain for their activity. We have addressed both of these major drawbacks. Firstly we have developed methods to efficiently express recombinant empty capsids. Expression constructs aimed at lowering the levels and activity of the viral protease required for the cleavage of the capsid protein precursor were used; this enabled the synthesis of empty A-serotype capsids in eukaryotic cells at levels potentially attractive to industry using both vaccinia virus and baculovirus driven expression. Secondly we have enhanced capsid stability by incorporating a rationally designed mutation, and shown by X-ray crystallography that stabilised and wild-type empty capsids have essentially the same structure as intact virus. Cattle vaccinated with recombinant capsids showed sustained virus neutralisation titres and protection from challenge 34 weeks after immunization. This approach to vaccine antigen production has several potential advantages over current technologies by reducing production costs, eliminating the risk of infectivity and enhancing the temperature stability of the product. Similar strategies that will optimize host cell viability during expression of a foreign toxic gene and/or improve capsid stability could allow the production of safe vaccines for other pathogenic picornaviruses of humans and animals. 相似文献
159.
We report on 2D plasmonic crystals composed of a hexagonal lattice of polymeric nanopillars embedded in an optically thick gold film on a glass substrate. A tapered shape of the polymeric pillars is proved to localize the electric field distribution close to the free surface of the device and to determine a significant increase in the electric field intensity particularly when the incident light comes from the glass side. These effects significantly improve the sample sensitivity to a refractive index change occurring at the free surface of the device. 相似文献
160.
Silvia C. Locatelli-Hoops Inna Gorshkova Klaus Gawrisch Alexei A. Yeliseev 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(10):2045-2056
Human peripheral cannabinoid receptor CB2, a G protein-coupled receptor (GPCR) involved in regulation of immune response has become an important target for pharmaceutical drug development. Structural and functional studies on CB2 may benefit from immobilization of the purified and functional receptor onto a suitable surface at a controlled density and, preferably in a uniform orientation. The goal of this project was to develop a generic strategy for preparation of functional recombinant CB2 and immobilization at solid interfaces. Expression of CB2 as a fusion with Rho-tag (peptide composed of the last nine amino acids of rhodopsin) in E. coli was evaluated in terms of protein levels, accessibility of the tag, and activity of the receptor. The structural integrity of CB2 was tested by ligand binding to the receptor solubilized in detergent micelles, captured on tag-specific monoclonal 1D4 antibody-coated resin. Highly pure and functional CB2 was obtained by sequential chromatography on a 1D4- and Ni-NTA-resin and its affinity to the 1D4 antibody characterized by surface plasmon resonance (SPR). Either the purified receptor or fusion CB2 from the crude cell extract was captured onto a 1D4-coated CM4 chip (Biacore) in a quantitative fashion at uniform orientation as demonstrated by the SPR signal. Furthermore, the accessibility of the extracellular surface of immobilized CB2 and the affinity of interaction with a novel monoclonal antibody NAA-1 was studied by SPR. In summary, we present an integral strategy for purification, surface immobilization, ligand- and antibody binding studies of functional cannabinoid receptor CB2. 相似文献