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61.
Duncker SC Lorentz A Schroeder B Breves G Bischoff SC 《Veterinary immunology and immunopathology》2006,111(3-4):239-250
Several beneficial effects of probiotics have been described in studies using rodent disease models and in human patients; however, the underlying mechanisms remained mostly unclear. Only a few studies focused on the effects of probiotics on the intestinal mucosal immune system. Here, we studied the effect of the probiotic strain E. coli Nissle 1917 (EcN) administered orally to young pigs at two concentrations (10(9) and 10(11)CFU/d for 21 days) on the gut-associated lymphatic tissue. This probiotic strain was shown recently to reduce recurrence of inflammation in ulcerative colitis patients. We quantified the number and distribution of intestinal immune cells (granulocytes, mast cells, CD4+, CD8+, CD25+, IgA+ lymphocytes) and the mucosal mRNA expression of cytokines (IFN-gamma, TNF-alpha, TGF-beta, IL-10) and antimicrobial peptides (PR-39, NK-lysin, prepro-defensin-beta 1, protegrins). The number and distribution of cells were highly different between small intestinal and colon segments in all groups, but were not influenced by EcN, except high dose EcN fed pigs (10(11) CFU/d) showing an increase in mucosal CD8+ cells in the ascending colon. The mRNA analysis revealed no changes associated with EcN feeding. In conclusion, according to our analyses EcN has only minor effects on the distribution of mucosal immune cells in the gut of healthy individuals. The well-established preventive effects of EcN might therefore be relate to other mechanisms than simple modulation of immune cell distribution. 相似文献
62.
Comparison of new foliar nutrient thresholds derived from van den Burg’s literature compilation with established central European references 总被引:1,自引:1,他引:0
In this paper, we suggest new nutrient threshold values and ratios for the major nutrients (N, P, K, Ca, Mg) for four main trees species Pinus sylvestris, Picea abies, Fagus sylvatica and Quercus (Q. robur and Q. petraea) statistically derived from the data collection of van den Burg’s literature compilation (1985, 1990), and compare them with widely used central European literature. The comparison is focused on the normal range of nutrition of major elements. We could show that the new critical foliar nutrient concentrations and ratios do not have the imponderabilities of the established reference systems, like restricted calibration range or data gaps for species in general or some major nutrients in particular. Ranges from the new critical foliar nutrient concentrations are generally smaller, except for broadleaves foliar Ca and Mg values, where another reference provides the narrowest ranges. The practicability of the different systems has been exemplary tested on a foliage data set of Norway spruce from the Bavarian soil survey. This application illustrates that an evaluation based on the new nutrient thresholds is in the majority of cases more cautious than the other reference systems. Moreover, evaluations based on the new concentrations and ratios are quite consistent. Comparisons with nutrient ratios related to the susceptibility to parasite attacks show that the thresholds are close to a general optimum range, indicating health and intact resistance mechanisms of these tree species. Uncertainties of the new threshold values as well as the need to further evaluate and develop reference systems for nutrient status of forest trees are discussed. 相似文献
63.
64.
Kloss S Wehrend A Failing K Bostedt H 《Berliner und Münchener tier?rztliche Wochenschrift》2002,115(7-8):247-251
The incidence of dystocia from ewes in nine lambing periods (1992-2000) was recorded at an obstetrical clinic. First we analysed parturition difficulties in normal pregnant sheep (group 1, n = 229). In the second group parturitions of ewes with vaginal prolapse ante partum were investigated (n = 129). In group 1 maternal causes of dystocia occurred more often than fetal ones (50% maternal, 45% fetal). In maternal parturition difficulties ringwomb was the dominating reason (64%), while abnormal presentations, position and/or posture of the lambs occurred most frequently in fetal dystocia (67%). But there was no statistical influence of age and number of parturitions in both groups. The average of the first notice of prolapsed vaginal tissue was 11 days before lambing. There was a predominance in the affection of sheep at first and second pregnancy (52%). Only 26% of the group 2 sheep had a spontaneous delivery. In 58% of the cases a dystocia was diagnosed. A preterm caesarean section had carried out in 12%, five ewes died before parturition because of septicemia (4%). Sheep suffering from vaginal prolapse ante partum showed maternal caused dystocia significant more frequently than members of group 1 (p < 0.001), with ringwomb as dominating reason (70%). The number of born lambs was significant higher in group 2 than in group 1 (p = 0.019). 相似文献
65.
Single-step purification and evaluation of recombinant BP26 protein for serological diagnosis of Brucella ovis infection in rams 总被引:1,自引:0,他引:1
Zygmunt MS Baucheron S Vizcaino N Bowden RA Cloeckaert A 《Veterinary microbiology》2002,87(3):213-220
To investigate the value of the BP26 protein in the serological diagnosis of ovine brucellosis caused by Brucella ovis, recombinant BP26 protein was produced in Echerichia coli and purified for use in an indirect enzyme-linked immunosorbent assay (I-ELISA). The majority of the recombinant protein was recovered from the supernatant of sonicated recombinant E. coli cells in a soluble form. This facilitated the purification of the recombinant BP26 protein which was achieved by using ion-exchange chromatography. After one step of purification, the purity of the recombinant BP26 protein was analyzed by using SDS-PAGE, Coomassie blue staining, and Western blot with a monoclonal antibody (MAb) directed against the BP26 protein. The degree of purity appeared satisfactory so that it could be directly used in I-ELISA. Although the recombinant BP26-ELISA appeared less useful than I-ELISA using the B. ovis hot saline (HS) extract as antigen, the high number of sera from B. ovis infected rams found positive (90%) in the recombinant BP26-I-ELISA indicated that the BP26 protein may be an additional suitable antigen for serological diagnosis of B. ovis infection in rams. 相似文献
66.
67.
Ohne Zusammenfassung
Schriftleitung 相似文献
68.
Establishing what caused Earth's largest climatic changes in the past requires a precise knowledge of both the forcing and the regional responses. We determined the chronology of high- and low-latitude climate change at the last glacial termination by radiocarbon dating benthic and planktonic foraminiferal stable isotope and magnesium/calcium records from a marine core collected in the western tropical Pacific. Deep-sea temperatures warmed by approximately 2 degrees C between 19 and 17 thousand years before the present (ky B.P.), leading the rise in atmospheric CO2 and tropical-surface-ocean warming by approximately 1000 years. The cause of this deglacial deep-water warming does not lie within the tropics, nor can its early onset between 19 and 17 ky B.P. be attributed to CO2 forcing. Increasing austral-spring insolation combined with sea-ice albedo feedbacks appear to be the key factors responsible for this warming. 相似文献
69.
I B Weinstein R Gebert U C Stadler J M Orenstein R Axel 《Science (New York, N.Y.)》1972,178(65):1098-1100
Type C RNA viruses are present in cell cultures from transplantable and primary hepatomas induced by aromatic amine carcinogens. Virus yield was markedly enhanced by treating the cells with bromodeoxyuridine. Preparations of rat hepatoma-associated virus obtained from cultures treated with this compound were deficient in DNA polymerase activity. 相似文献
70.
Hess M Sczyrba A Egan R Kim TW Chokhawala H Schroth G Luo S Clark DS Chen F Zhang T Mackie RI Pennacchio LA Tringe SG Visel A Woyke T Wang Z Rubin EM 《Science (New York, N.Y.)》2011,331(6016):463-467
The paucity of enzymes that efficiently deconstruct plant polysaccharides represents a major bottleneck for industrial-scale conversion of cellulosic biomass into biofuels. Cow rumen microbes specialize in degradation of cellulosic plant material, but most members of this complex community resist cultivation. To characterize biomass-degrading genes and genomes, we sequenced and analyzed 268 gigabases of metagenomic DNA from microbes adherent to plant fiber incubated in cow rumen. From these data, we identified 27,755 putative carbohydrate-active genes and expressed 90 candidate proteins, of which 57% were enzymatically active against cellulosic substrates. We also assembled 15 uncultured microbial genomes, which were validated by complementary methods including single-cell genome sequencing. These data sets provide a substantially expanded catalog of genes and genomes participating in the deconstruction of cellulosic biomass. 相似文献