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Phenotypic and functional analysis of bovine peripheral blood dendritic cells before parturition by a novel purification method 下载免费PDF全文
Tao Zhuang Megumi Urakawa Hidetoshi Sato Yuko Sato Teruaki Taguchi Tsuyoshi Umino Shiro Katto Koutaro Tanaka Kozue Yoshimura Naokazu Takada Hiroko Kobayashi Megumi Ito Michael T. Rose Yoshio Kiku Yuya Nagasawa Haruki Kitazawa Kouichi Watanabe Tomonori Nochi Tomohito Hayashi Hisashi Aso 《Animal Science Journal》2018,89(7):1011-1019
Dendritic cells (DCs) are specialized antigen presenting cells specializing in antigen uptake and processing, and play an important role in the innate and adaptive immune response. A subset of bovine peripheral blood DCs was identified as CD172a+/CD11c+/MHC (major histocompatibility complex) class II+ cells. Although DCs are identified at 0.1%–0.7% of peripheral blood mononuclear cells (PBMC), the phenotype and function of DCs remain poorly understood with regard to maintaining tolerance during the pregnancy. All cattle used in this study were 1 month before parturition. We have established a novel method for the purification of DCs from PBMC using magnetic‐activated cell sorting, and purified the CD172a+/CD11c+ DCs, with high expression of MHC class II and CD40, at 84.8% purity. There were individual differences in the expressions of CD205 and co‐stimulatory molecules CD80 and CD86 on DCs. There were positive correlations between expression of cytokine and co‐stimulatory molecules in DCs, and the DCs maintained their immune tolerance, evidenced by their low expressions of the co‐stimulatory molecules and cytokine production. These results suggest that before parturition a half of DCs may be immature and tend to maintain tolerance based on the low cytokine production, and the other DCs with high co‐stimulatory molecules may already have the ability of modulating the T‐cell linage. 相似文献
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This study focuses on the longevity data accumulated for the family Estrildidae, specifically exploring longevity records for each species using ringing data. Longevity is the minimum age reached by an individual as determined by the time elapsed between initial ringing and last recapture or recovery date. In southern Africa bird ringing started in 1948 and is managed by the South African Bird Ringing Scheme. For estrildids, there are 151 831 ringing records. Approximately 7.0% of those ringed individuals have since been resighted, retrapped or recovered. This family is poorly studied and more research is necessary, particularly as certain estrildid species have been highlighted as data-deficient whilst others are potentially of conservation concern. The South African Bird Ringing scheme (SAFRING) has longevity records for 23 of the 27 southern Africa estrildid species. The maximum longevity record was 10.9 years (Blue Waxbill Uraeginthus angolensis). The overall average longevity for an individual is 3.7 years (SD = 2.5). The low longevity values make sense given the low mass (6.3–22.7 g) of estrildids. Coupled with large clutch sizes of four eggs on average, as well as potentially low surivival, estrildids may counter low longevity by breeding at an early age and double-brooding. 相似文献
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V Aksyuk FF Balakirev GS Boebinger PL Gammel RC Haddon DJ Bishop 《Science (New York, N.Y.)》1998,280(5364):720-722
A silicon micromechanical magnetometer was constructed and successfully used in 60-tesla pulsed magnetic fields of less than 100-millisecond duration. The device is small, inexpensive to fabricate, and easy to use. It features a fast mechanical response (up to 50,000 hertz) and extremely high sensitivity yet is relatively robust against electrical and mechanical noise. Quantum oscillations in the magnetization of a 1-microgram sample of an organic superconductor, kappa-[bis(ethylenedithio)tetrathiafulvalene]2Cu(NCS)2, have been observed with this device. 相似文献
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S. Manninen D. Le Thiec C. Rose G. Nourrisson F. Radnai J.P. Garrec S. Huttunen 《Water, air, and soil pollution》1999,116(1-2):333-338
Two-year-old Aleppo pine (Pinus halepensis Mill.) seedlings were exposed to ambient air+50 ppb O3 in open-top chambers (24 hours/day, 7 days/week) during May-October 1997 and to ambient air+70 ppb O3 from May 1998 onwards. One growing season fumigation with ozone did not affect the pigment concentrations of the current-year (c) needles, nor were there any differences in photosynthesis or stomatal conductance. In May 1998, however, a marked carry-over effect was seen in the chlorophyll a and b and total carotenoid concentrations of the O3-fumigated one-year-old (c+1) needles. The chlorophyll a and b and total carotenoid concentrations of newly flushed needles of the O3-fumigated seedlings also seemed to be slightly decreased, as was their net photosynthesis when compared to the values of the filtered-air control needles. The chlorotic mottle and the changes in chloroplast pigments and photosynthesis of the c and/or c+1 needles of the NFA+O33 seedlings in May 1998 indicate that frequent episodes of ozone concentrations of ≥100 ppb, especially when they also occur during the evening and night hours, as in some areas in southern Europe, may result in visible needle damage on Aleppo pine. 相似文献
149.
N. Rose F. Beaudeau P. Drouin J. Y. Toux V. Rose P. Colin 《Preventive veterinary medicine》1999,39(4):1158
Broiler-chicken are often Salmonella carriers. However, these bacteria are responsible for major food-borne human infection, in which poultry-meat products are frequently implicated. In order to prevent Salmonella spread during the slaughtering process, control measures should be implemented at the farm level to reduce the prevalence before slaughtering. The objective of this study was to identify the risk factors for Salmonella contamination in French commercial broiler flocks at the end of the rearing period. A prospective study was carried out in 1996 and 1997 on 86 broiler flocks located in western France. The Salmonella status of the flocks was assessed by means of litter swabs and dust samples analyzed with classical bacteriological methods. Sixty flocks (70%) had at least one contaminated environmental sample and were classified as Salmonella-contaminated flocks. Logistic regression was used to assess association of managerial practices, general hygiene and results of environmental Salmonella recovery, with the odds that the flock itself would be Salmonella-contaminated at the end of the rearing period. Salmonella contamination of the house before placing day-old chicks and the Salmonella contamination of day-old chicks were significantly related to Salmonella contamination of the flock at the end of the rearing period. The risk for Salmonella contamination of the flock was increased when feed trucks parked near the entrance of the change room and when feed meal, instead of small pellets, was provided at the start. 相似文献
150.
B M Alexander J N Stellflug J D Rose J A Fitzgerald G E Moss 《Journal of animal science》1999,77(7):1869-1874
High-performing, low-performing, and male-oriented rams were used to investigate behavior and neuroendocrine correlates of sexual interest and discrimination. Treatment consisted of visual and olfactory contact with stimulus animals through a woven wire fence, which inhibited copulation (either ewes in estrus or other rams), for 4 h on each of three consecutive days. Before exposure to stimulus animals on d 1 and during the final 1 h of exposure on d 2, blood samples were collected every 15 min for 1 h to determine concentrations of LH and testosterone. During exposure to stimulus animals, rams were continuously observed and investigatory behaviors were recorded. There was no day effect for any behavior. Groups of rams differed (P < .05) in amounts of behaviors exhibited, but behaviors were not influenced by sex of stimulus animals. High-performing rams exhibited more (P < .05) investigatory behaviors toward stimulus animals than low-performing or male-oriented rams. Plasma concentrations of LH increased (P < .05) in high-performing rams following exposure to estrous ewes, but not following exposure to rams. In low-performing and male-orientated rams, concentrations of LH were unchanged regardless of sex of the stimulus animal. Change in plasma concentrations of testosterone from pre- to posttreatment did not differ between high-performing, low-performing, and male-oriented rams. However, low-performing rams exhibited an increase (P < .05) in plasma concentrations of testosterone following exposure to rams. In conclusion, high-performing rams exhibit a high degree of investigatory behaviors toward estrous ewes and other rams. High-performing rams seem to discriminate sex of stimulus animals and exhibit a neuroendocrine response (i.e., increased plasma LH) only when exposed to ewes in estrus. The sensory signals provided by estrous females are either not detected by low-performing or male-oriented rams or are not sufficiently provocative to elicit further investigation by these rams. 相似文献