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71.
Traute Jan?en Matthias Voss Michael Kühl Torsten Semmler Hans-Christian Philipp Christa Ewers 《Veterinary research》2015,46(1)
Erysipelothrix rhusiopathiae infections re-emerged as a matter of great concern particularly in the poultry industry. In contrast to porcine isolates, molecular epidemiological traits of avian E. rhusiopathiae isolates are less well known. Thus, we aimed to (i) develop a multilocus sequence typing (MLST) scheme for E. rhusiopathiae, (ii) study the congruence of strain grouping based on pulsed-field gel electrophoresis (PFGE) and MLST, (iii) determine the diversity of the dominant immunogenic protein SpaA, and (iv) examine the distribution of genes putatively linked with virulence among field isolates from poultry (120), swine (24) and other hosts (21), including humans (3). Using seven housekeeping genes for MLST analysis we determined 72 sequence types (STs) among 165 isolates. This indicated an overall high diversity, though 34.5% of all isolates belonged to a single predominant ST-complex, STC9, which grouped strains from birds and mammals, including humans, together. PFGE revealed 58 different clusters and congruence with the sequence-based MLST-method was not common. Based on polymorphisms in the N-terminal hyper-variable region of SpaA the isolates were classified into five groups, which followed the phylogenetic background of the strains. More than 90% of the isolates harboured all 16 putative virulence genes tested and only intI, encoding an internalin-like protein, showed infrequent distribution. MLST data determined E. rhusiopathiae as weakly clonal species with limited host specificity. A common evolutionary origin of isolates as well as shared SpaA variants and virulence genotypes obtained from avian and mammalian hosts indicates common reservoirs, pathogenic pathways and immunogenic properties of the pathogen.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-015-0216-x) contains supplementary material, which is available to authorized users. 相似文献72.
Andreas VERNUNFT Mona SCHWERHOFF Torsten VIERGUTZ Mike DIEDERICH Andreas KUWER 《The Journal of reproduction and development》2015,61(1):74-79
The aim of this study was to investigate whether plasma anti-Muellerian hormone (AMH) levels of Holstein-Friesian heifers could be used to predict ovum pick-up (OPU) and embryo production outcomes. Plasma samples and data were collected from 64 heifers, which underwent repeated OPU with subsequent in vitro embryo production followed by embryo flushing after superovulation. AMH levels were significantly positively correlated with the number of follicles aspirated per OPU session (r = 0.45), recovered oocytes per OPU (r =0.43) and in vitro produced embryos per OPU (r = 0.28). No significant correlations between AMH and in vivo produced embryos were ascertained. Our results suggest that correlations between AMH and outcomes of an OPU-IVF program are too low to use AMH as a precise predictive parameter for the success of a particular OPU procedure in Holstein-Friesian heifers. However, AMH can help to identify groups of
very good or very poor oocyte donors. 相似文献
73.
Oevermann A Botteron C Seuberlich T Nicolier A Friess M Doherr MG Heim D Hilbe M Zimmer K Zurbriggen A Vandevelde M 《Veterinary microbiology》2008,130(3-4):320-329
This paper describes the prevalence of brain lesions in the Swiss fallen stock population of small ruminants. 3075 whole brains (75% sheep, 25% goats) were collected as part of a year-long active survey of transmissible spongiform encephalopathies (TSEs) in small ruminants conducted by the Swiss authorities between July 2004 and July 2005. All fallen stock brains were systematically examined by histopathology to obtain reliable data on histologically identifiable brain lesions. Lesions were found in an unexpectedly high number of animals (8.1% of all examined brains). A wide spectrum of diseases was detected showing that this approach provides an excellent opportunity to screen for the prevalence of neurological diseases. Encephalitic listeriosis was by far the most frequent cause of CNS lesions in both species and its prevalence was unexpectedly high when compared to notified confirmed cases. In conclusion, the prevalence of listeriosis as estimated by passive surveillance based on the notification of clinical suspects has been underestimated in the past. 相似文献
74.
Torsten W. Berger Erich Inselsbacher Franz Mutsch Michael Pfeffer 《Forest Ecology and Management》2009,258(11):2578-2592
Studies on the combined effects of beech–spruce mixtures are very rare. Hence, forest nutrition (soil, foliage) and nutrient fluxes via throughfall and soil solution were measured in adjacent stands of pure spruce, mixed spruce–beech and pure beech on three nutrient rich sites (Flysch) and three nutrient poor sites (Molasse) over a 2-year period. At low deposition rates (highest throughfall fluxes: 17 kg N ha−1 year−1 and 5 kg S ha−1 year−1) there was hardly any linkage between nutrient inputs and outputs. Element outputs were rather driven by internal N (mineralization, nitrification) and S (net mineralization of organic S compounds, desorption of historically deposited S) sources. Nitrate and sulfate seepage losses of spruce–beech mixtures were higher than expected from the corresponding single-species stands due to an unfavorable combination of spruce-similar soil solution concentrations coupled with beech-similar water fluxes on Flysch, while most processes on Molasse showed linear responses. Our data show that nutrient leaching through the soil is not simply a “wash through” but is mediated by a complex set of reactions within the plant–soil system. 相似文献
75.
76.
Experimental plots within the Hubbard Brook Experimental Forest, NH, were treated with sodium trifluoroacetate (TFA) and lithium bromide (Br), to study the impact of TFA alone and in the presence of increased anion concentrations (e.g. acid deposition) on the soil solution chemistry of a northern hardwood forest soil. Trifluoroacetate is a major atmospheric degradation product of replacement compounds of chlorofluorocarbons (CFC) and Br is widely used as a hydrologic tracer. Calculated drainage losses via soil water flow were less than 60% of inputs, added during the summer, and TFA and Br were temporarily retained in the soil until fall. The initial indication of an acid input of the treatments (HTFA, HBr) in the Bs2 horizon, which reflects stream water chemistry as well, was an increase of base cations in the soil solution, decreasing the soil's acid neutralizing capacity. Thereafter, trifluoroacetate and Br concentrations peaked after the peak in base cations, synchronous with peaks in H+ and Al concentrations. Organic anions, nitrate and chloride played the major role in accompaning base cations out of the solum. Sulfate retention at soil adsorption sites was increased by the presence of TFA and Br, reducing its role as a mobile anion of base cations in this experiment. Relative retention of anions for the whole profile of this northern hardwood forest soil was estimated by correlation analyses and input-output balances in decreasing order on an equivalant basis: SO4 > TFA = Br ≥ Cl > NO3 > organic anions. Recovery from acid additions were recorded within several weeks after the treatments were stopped. Evaluating the impact of added chemical compounds to soils must be considered within the context of linkages among element cycles and pools. 相似文献
77.
This study evaluates employment patterns of domestic migrants and immigrants and also explores the role of ethnic niching for Asian and African American recent arrivals in the context of local structural transformation (e.g., the shift from manufacturing to services). Employment patterns are examined for industry-occupation groups using the 5% Public Use Micro Sample of the 2000 U.S. Decennial Census and the 2006–2010 of the American Community Survey. The study area is a Rustbelt city that has suffered from population loss: the Buffalo-Niagara Falls MSA. Location quotients and shift-share analysis are used to classify employment shifts into four industry-occupation groups: growing, transforming, declining, and emerging. Logistic regressions are estimated to identify the role of various demographic factors and ethnic niches on the employment of recent arrivals in the above four industry-occupation groups. The results show that the employment of recent arrivals vary by migration status and ethnicity. The role of ethnic niches is especially important in declining industry-occupation groups. The analytical framework can be used to understand where and how migrants, both domestic and immigrants, find work. Future studies can focus on the pros and cons of ethnic niching (e.g., barriers to suitable jobs, ethnic entrepreneurship through niche experience) as structural transformation continues across U.S. regions, especially with new technologies. 相似文献
78.
Development of sediment quality criteria in Norway 总被引:1,自引:0,他引:1
Torgeir Bakke Torsten Källqvist Anders Ruus Gijs D. Breedveld Ketil Hylland 《Journal of Soils and Sediments》2010,10(2):172-178
Introduction
A Norwegian system for classification of environmental quality of contaminated marine sediments has been in force since 1997 and was revised in 2007. 相似文献79.
Unlu NZ Bohn T Francis D Clinton SK Schwartz SJ 《Journal of agricultural and food chemistry》2007,55(4):1597-1603
Tomato sauces were produced from unique tomato varieties to study carotenoid absorption in humans. Tangerine tomatoes, high in cis-lycopene, especially prolycopene (7Z,9Z,7'Z,9'Z), and high-beta-carotene tomatoes as an alternative dietary source of beta-carotene were grown and processed. Sauces were served after 2 week washout periods and overnight fasting for breakfast to healthy subjects (n = 12, 6M/6F) in a randomized crossover design. The serving size was 150 g (containing 15 g of corn oil), tangerine sauce containing 13 mg of lycopene (97.0% as cis-isomers) and high-beta-carotene sauce containing 17 mg of total beta-carotene (1.6% as the 9-cis-isomer) and 4 mg of lycopene. Blood samples were collected 0, 2, 3, 4, 5, 6, 8, and 9.5 h following test meal consumption and carotenoids determined in the plasma triacylglycerol-rich lipoprotein fraction by HPLC-electrochemical detection. Baseline-corrected areas under the concentration vs time curves (AUC) were used as a measure of absorption. AUC0-9.5h values for total lycopene in the tangerine sauce group were 870 +/- 187 (nmol.h)/L (mean +/- SEM) with >99% as cis-isomers (59% as the tetra-cis-isomer). The AUC0-9.5h values for total beta-carotene and lycopene after consumption of the high-beta-carotene sauce were 304 +/- 54 (4% as 9-cis-carotene) and 118 +/- 24 (nmol.h)/L, respectively. Lycopene dose-adjusted triacylglycerol-rich lipoprotein AUC responses in the tangerine sauce group were relatively high when compared to those in the literature and the high-beta-carotene group. The results support the hypothesis that lycopene cis-isomers are highly bioavailable and suggest that special tomato varieties can be utilized to increase both the intake and bioavailability of health-beneficial carotenoids. 相似文献
80.
Olszak T An D Zeissig S Vera MP Richter J Franke A Glickman JN Siebert R Baron RM Kasper DL Blumberg RS 《Science (New York, N.Y.)》2012,336(6080):489-493
Exposure to microbes during early childhood is associated with protection from immune-mediated diseases such as inflammatory bowel disease (IBD) and asthma. Here, we show that in germ-free (GF) mice, invariant natural killer T (iNKT) cells accumulate in the colonic lamina propria and lung, resulting in increased morbidity in models of IBD and allergic asthma as compared with that of specific pathogen-free mice. This was associated with increased intestinal and pulmonary expression of the chemokine ligand CXCL16, which was associated with increased mucosal iNKT cells. Colonization of neonatal-but not adult-GF mice with a conventional microbiota protected the animals from mucosal iNKT accumulation and related pathology. These results indicate that age-sensitive contact with commensal microbes is critical for establishing mucosal iNKT cell tolerance to later environmental exposures. 相似文献