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Taras Y. Nechitaylo Kenneth N. Timmis Boris A. Byzov Elena Belogolova Manuel Ferrer 《Soil biology & biochemistry》2010,42(7):1168-1171
Prions represent the active agent in transmissible spongiform encephalopathy (TSE) diseases and can remain infective to mammals even after prolonged periods in soil. The influence of mesofauna on prion dispersal and degradation in soil, however, remains unknown. In this study the effect of earthworms on the retention/dissemination of TSEs in soil was evaluated using a model recombinant prion protein (recPrP) and aqueous extracts from soil and fresh casts of two earthworm species, Lumbricus terrestris and Aporrectodea caliginosa. Our results showed that earthworm gut-derived enzymes did not enhance the degradation of recPrP in comparison to soil, even though non-prion related proteolytic activity was higher in fresh worm excrements than in soil samples. Complete degradation of recPrP occurred in the aqueous extracts from all samples within up to 6 days at +15 °C. The proteolytic enzymes responsible for degrading recPrP were inhibited by aprotinin and leupeptin and studies in pure cultures suggested these were most probably of soil microbial origin. 相似文献
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Schierack P Filter M Scharek L Toelke C Taras D Tedin K Haverson K Lübke-Becker A Wieler LH 《Veterinary immunology and immunopathology》2009,127(1-2):26-37
Changing immune parameters during pregnancy have previously been reported in humans and cattle, and have been suggested to contribute to increased susceptibility to infections. However, data regarding immune parameters during pregnancy in sows are rare. In this study, we investigated the peripartal immune status of sows using phenotypical (FACS analysis) as well as functional (proliferation assays, cytokine analysis) parameters of peripheral blood mononuclear cells (PBMCs) in pregnant sows. In previous studies, we reported a modulation of the immune system after feed supplementation of the probiotic Bacillus cereus var. toyoi in piglets [Schierack, P., Wieler, L.H., Taras, D., Herwig, V., Tachu, B., Hlinak, A., Schmidt, M.F., Scharek, L., 2007. Bacillus cereus var. toyoi enhanced systemic immune response in piglets. Vet. Immunol. Immunopathol. 118, 1–11]. Here, we extended these previous studies to include investigations of possible probiotic effects on the peripartal immune status of sows and their reproductivity. We show that immune parameters of sows change during pregnancy, the proliferative response of PBMCs to several bacterial antigens in control animals decreased from days 90 to 30 ante partum. Relative numbers (%) of CD3+CD8+, CD4+, cytotoxic T, CD14+ and CD21+ cells were reduced compared to non-pregnant sows. In contrast, the proliferative response of PBMCs of probiotic-treated sows increased during pregnancy. Bacterial antigens primarily stimulated the proliferation of naïve CD21+ cells and the relative CD21+ cell numbers were elevated in the probiotic group in the absence of effects on other immune cell populations. The clinical and microbial status of both control and probiotic sows was similar, excluding pre-existing health problems or infections as responsible for the immunological changes, and feed supplementation also had no significant effects on reproductivity. The results suggest that the probiotic B. cereus var. toyoi can alter the proliferative response of lymphocytes and affects the immune cell population ratios of pregnant sows. How and to what extent this may affect health and reproductivity should be the focus of further studies. 相似文献
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Kraatz M Taras D Männer K Simon O 《Journal of animal physiology and animal nutrition》2006,90(9-10):361-368
Two 6-week feeding trials were conducted on a total of 112 newly weaned piglets to examine the recently reported growth promoting effects of dietary rare earth elements (REE) in European pig production. Rare earth element-diets were supplemented with a REE-citrate premix of lanthanum and the light lanthanoides cerium, praseodymium and neodymium at 200 mg/kg for 6 weeks after weaning. Overall for both trials, growth performance of REE-citrate and control fed piglets did not differ significantly (p > 0.05). An early enhancive tendency for REE-citrate in trial 1 (feed conversion ratio, FCR -3%, p = 0.15) proved irreproducible in trial 2. In the late period of trial 1, in-feed addition of REE-citrate significantly impaired piglet performance (FCR + 8%, p = 0.01). A cultivation-independent molecular approach, polymerase chain reaction-denaturing gradient gel electrophoresis was further applied to assess REE induced alterations in the predominant faecal microbiota from weaning pigs. Calculation of various ecological characteristics does not indicate (p > 0.05) an often discussed selective effect on local microbial composition of dietary REE. 相似文献
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Two probiotics of different ecological origin, Enterococcus faecium NCIMB 10415 and Bacillus cereus var. toyoi, were chosen as model organisms. Feed for sows during gestation/lactation and for piglets pre-/postweaning was supplemented with either of these probiotics. To evaluate the effect of different starting points of E. faecium NCIMB 10415 initiations the probiotic was administered to piglets of sows, which have not received the probiotic, from birth onwards or just postweaning. Here we report the impact of these variants on probiotic distribution in the gut, on the gut microbiota, on diarrhea and on performance. Both probiotic strains were detected immediately after the start of the supplementation in feces of sows and piglets. The vertical transfer of both probiotic strains with sow feces to piglets could be demonstrated already before suckling piglets had access to the supplemented diets. Both probiotics were recovered from all intestinal segments of piglets. The dominant autochthonous colonic microbiota of young piglets as revealed by denaturing gradient gel electrophoresis was more similar within than between treatment groups (control vs. probiotic). Both probiotics reduced the incidence of postweaning diarrhea (p < 0.05). For the E. faecium probiotic the relative magnitude of this effect was largely independent of dietary probiotic concentration or starting time of supplementation. Significant overall influence on piglet performance was observed only with the B. cereus probiotic. 相似文献
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Sarkki Simo Parpan Taras Melnykovych Mariana Zahvoyska Lyudmyla Derbal Juriy Voloshyna Nataliya Nijnik Maria 《Landscape Ecology》2019,34(7):1601-1618
Tuning participatory processes is often insufficient to achieve transition from authoritative state to democratic and participatory forest governance due to institutional inertia and unwillingness to truly decentralize decision-making power. Social innovations as reconfigurations of relationships between state, market actors, civil society and science can help to meet concerns of local people about forest Ecosystem Services (ES). In Ukraine, the Swiss-Ukrainian Forest Development (FORZA) pilot project initiated a social innovation process complementing regional forest planning with local participatory community development plans in Transcarpathia. This paper examines what kind of changes need to accompany the succession of participatory practices in transition processes from authoritative state to democratic forest governance, and what are the lessons learned for social innovations based on the Ukrainian case study. This paper synthesizes knowledge on the FORZA case analyzed by inductive content analysis, and integrates these local level results with a national survey (N?=?244) on Ukrainian forest governance. Transition processes need to go “beyond participation” by (i) legal reforms to better acknowledge ES important for local people, (ii) a change from an exclusive focus on timber to acknowledging multiple ES, (iii) changed spatial and temporal rationales of state-based governance, and (iv) recognition of local people as credible experts. Social innovations can detect key barriers to the transition during the policy experiments, and need to pay significant attention on how the novel practices can be sustained after the pilot, replicated elsewhere and up-scaled. Without such considerations, social innovation projects may only remain as a marginal curiosity.
相似文献7.
Scharek L Guth J Reiter K Weyrauch KD Taras D Schwerk P Schierack P Schmidt MF Wieler LH Tedin K 《Veterinary immunology and immunopathology》2005,105(1-2):151-161
The influence of the probiotic bacterium Enterococcus faecium SF68 on the immune system and the intestinal colonization of pigs were determined in a feeding experiment with sows and piglets. Mucosal immunity of the developing piglets was monitored by isolation and detection of intestinal lymphocyte cell populations from the proximal jejunal epithelium and the continuous Peyers patches by the use of flow cytometry. The levels of intestinal IgA in both groups of piglets were compared, as well as total IgG in the serum of sows and piglets. Feces of the sows and intestinal contents of the piglets were taken for determination of total anaerobe and coliform bacterial counts in both probiotic and control groups. Villus length and depth of the crypts were measured in the jejunum of sacrificed piglets to monitor the development of the intestinal mucosal surface amplification. Total serum IgG of the sows appeared to be unaffected. Piglets of both groups showed similar IgG levels up to 5 weeks after birth with a slight tendency toward lower values in the probiotic group. At an age of 8 weeks the total IgG levels of the probiotic animals were significantly lower (p<0.01). No differences were observed in the populations of CD4+ and CD8+ T cells in the Peyers patches. However, the levels of cytotoxic T cells (CD8+) in the jejunal epithelium of piglets of the probiotic group were significantly reduced. The depth of the jejunal crypts and length of the villi were similar in both groups, suggesting the relative T-cell population differences were not due to alterations in the epithelial cell numbers. The total anaerobe and coliform bacterial populations were not significantly affected by the probiotic treatment, either in sows or in the piglets. However, a remarkable decline in the frequency of beta-haemolytic and O141 serovars of Escherichia coli was observed in the intestinal contents of probiotic piglets, suggesting an explanation for the reduction in cytotoxic T-cell populations. 相似文献
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As part of an interdisciplinary research project, the performance response of sows and their litters to the probiotic strain Enterococcus faecium NCIMB 10415, as well as some health characteristics of the piglets, were studied. Gestating sows (n = 26) were randomly allotted into 2 groups. The probiotic was administered by dietary supplementation to 1 group of sows and their respective litters (probiotic group), whereas the second group (control group) received no probiotic supplementation. The duration of the treatment was nearly 17 wk for sows (d 90 ante partum until d 28 postpartum) and 6 wk for piglets (d 15 to 56). Body weight and feed consumption were recorded weekly. The frequency of 4 toxin and 5 adhesion genes of putative pathogenic Escherichia coli was monitored weekly (d 7 to 35) by multiplex PCR assays, and fecal consistency of weaned piglets was studied daily. Probiotic treatment of lactating sows led to an overall pre-weaning mortality of 16.2% compared with 22.3% in the control group (P = 0.44). Animal losses during the first 3 d of the suckling period were decreased in the probiotic group (P = 0.09). For piglets (n = 153), which were weaned at 28 d, there were no overall treatment differences in BW gain, feed intake, or feed efficiency. Probiotic supplementation, however, led to nearly a 40% reduction (P = 0.012). The actual percentage of piglets with postweaning diarrhea in the probiotic group was 21% compared with 38% in the control group (P = 0.05). The study on virulence factors of dominant fecal E. coli isolates revealed a high diversity with varying frequency and distribution of each single pathogenicity gene. The 440 isolates carried 29 different pathogenicity gene combinations as well as each of the 9 pathogenicity genes alone. Altogether, isolates with more than 2 pathogenicity genes were quite rare (< or = 10%), and up until d 28 isolates without any pathogenicity gene occurred most frequently. Depending on the time of sampling, one-third or more of all isolates contained est2 or est1b as single gene or in combination with other pathogenicity genes. 相似文献
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Schierack P Wieler LH Taras D Herwig V Tachu B Hlinak A Schmidt MF Scharek L 《Veterinary immunology and immunopathology》2007,118(1-2):1-11
Probiotic bacteria have been suggested to stimulate the host immune system. In this study we evaluated the immunomodulatory effects of probiotic Bacillus cereus var. toyoi on the systemic immunity of piglets. A pool of 70 piglets was divided into a probiotic or control group. We determined the ratios of peripheral blood mononuclear cell (PBMC) subsets and measured proliferative responses and cytokine production of PBMCs and effects on vaccination responses. Blood samples of probiotic-treated piglets showed a significantly lower frequency of CD8(high)/CD3+ T cells and CD8(low)/CD3+ T cells and a significant higher CD4+/CD8+ ratio. IL-4 and IFN-gamma production of polyclonally stimulated PBMCs was on average higher in the probiotic group. Specific proliferative responses of PBMCs to Influenza vaccination antigens were significantly higher and antibody titers against H3N2 Influenza and Mycoplasma vaccination antigens were on average higher in the probiotic group. In conclusion, B. cereus var. toyoi therefore alters the immune status of piglets as indicated by changes in the ratios as well as functionalities of systemic immune cell populations. 相似文献
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Rapid advances in microscopy have boosted research on cell biology. However sample preparation enabling excellent reproducible tissue preservation and cell labeling for in depth microscopic analysis of inner cell layers, tissues and organs still represents a major challenge for immunolocalization studies. Here we describe a protocol for whole-mount immunolocalization of proteins which is applicable to a wide range of plant species. The protocol is improved and robust for optimal sample fixation, tissue clearing and multi-protein staining procedures and can be used in combination with simultaneous detection of specific sequences of nucleic acids. In addition, cell wall and nucleus labelling can be implemented in the protocol, thereby allowing a detailed analysis of morphology and gene expression patterns with single-cell resolution. Besides enabling accurate, high resolution and reproducible protein detection in expression and localization studies, the procedure takes a single working day to complete without the need for robotic equipment. 相似文献