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21.
Tomioka I Mizutani E Yoshida T Sugawara A Inai K Sasada H Sato E 《The Journal of reproduction and development》2007,53(4):835-842
The present study was conducted to demonstrate the spindle formation and behavior of chromosomes and microtubules during first division in reconstructed rat embryos produced by somatic cell nuclear transfer (SCNT) with cumulus cell nuclei. To demonstrate the effect of oocyte aging after ovulation on the cleavage of SCNT embryos, micromanipulation was carried out 11, 15 and 18 h after injection of hCG. SCNT oocytes were activated by incubation in culture medium supplemented with 5 microM ionomycin for 5 min followed by treatment with 2 mM 6-dimethylaminopurine (6-DMAP) in mR1ECM for 2-3 h. For immunocytochemical observation, the SCNT embryos were incubated with monoclonal anti-alpha-tubulin antibody and then fluorescein isothiocyanate (FITC)-conjugated goat anti-mouse IgG. Cleavage rates were significantly higher for oocytes collected after 15 and 18 h rather than for those collected 11 h after injection of hCG (56 and 53%, respectively vs. 28%; P<0.05). Premature chromosome condensation occurred before activation of the SCNT oocytes, but adequate spindle formation was only rarely observed. The distribution of microtubules in SCNT embryos after activation was different from those of fertilized and parthenogenic oocytes, i.e., a dense microtubule organization shaped like a ring was observed. Eighteen to 20 h post-activation, most SCNT embryos were in the 2-cell stage, but no nucleoli were clearly visible, which was quite different from the fertilized oocytes. In addition, first division with and without small cellular bodies containing DNA was observed in the rat SCNT embryos in some cases. The present study suggests that reorganization of transferred nuclei in rat SCNT embryos may be inadequate in terms of formation of the mitotic assembly and nucleolar reorganization. 相似文献
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A novel culture method of canine peripheral blood lymphocytes with concanavalin a and recombinant human interleukin-2 for adoptive immunotherapy 总被引:1,自引:0,他引:1
Kato M Watarai S Nishikawa S Iwasaki T Kodama H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(5):481-486
This study was designed to develop a novel culture method for the efficient proliferation of canine peripheral blood lymphocytes (cPBL) for adoptive immunotherapy. When cPBL were cultured in the presence of concanavalin A (Con A), proliferation of cPBL was induced and expression of interleukin-2 receptor (IL-2R) which enables to respond to exogenously added IL-2 was upregulated. And then, when cPBL were cultured with recombinant human interleukin-2 (rhIL-2) in addition to Con A, proliferation was accelerated and increased to about 10-fold after 1 week. The phenotypic analysis showed that the main population of the cultured cPBL was consisted of CD8+ positive lymphocytes. Among them, CD4+CD8+ double positive (DP) lymphocytes had significantly increased, and the ratio of CD4+ single positive (SP) lymphocytes to CD8+ SP lymphocytes (CD4+SP/CD8+SP) was decreased as compared to before culturing. To evaluate the cytotoxic activity of cPBL cultured with Con A and rhIL-2, furthermore, cytotoxic assay was carried out against xenogeneic melanoma cell line (MeWo), which resulted in MHC-unrestricted cytokilling. These results suggest that the culture method of cPBL by the use of Con A and rhIL-2 may be useful for generating lymphokine activated killer cells, and also this may be beneficial for adoptive immunotherapy of tumor-bearing dogs. 相似文献
24.
To control rice blast effectively at the nursery stage, the absolute SiO2 content necessary for rice plants to resist blast disease was investigated using various rice cultivars and soils. Nine rice cultivars with different complete resistance genes and different degrees of partial resistance were grown on nursery soils amended with silica gel at different rates to change the SiO2 content of rice plant. The rice seedlings were then inoculated 28 days after sowing with Pyricularia grisea to estimate their blast resistance. In all rice cultivars, the number of lesions was significantly reduced when SiO2 content increased in the rice seedling; lesions were reduced to 5%–20% of the number on the seedlings grown in soil without silica gel when the seedling SiO2 content reached 5%. Additionally, the susceptibility to blast disease of rice seedlings grown on eight soils collected from different districts, with varying amounts of silica gel, was compared. The number of lesions decreased significantly when the SiO2 content in the seedlings reached 5%. These results suggest that SiO2 content of at least 5% in the rice plant can control this disease at the nursery stage under any conditions. 相似文献
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Nakano S Kishi H Ogawa H Yasue H Okano A Okuda K 《The Journal of reproduction and development》2003,49(2):127-134
We investigated endometrial expression of trophinin mRNA and protein, homophilic cell adhesion molecules, during the estrous cycle of gilts. An immunopositive reaction for trophinin was observed in the luminal and glandular epithelia of the endometrium at all stages of the estrous cycle, but not in endometrial stromal cells or the myometrium. A partial coding sequence of porcine trophinin was similar to sequences in humans and mice, with homologies of 75% and 70%, respectively. As in humans and mice, the trophinin gene is expressed in the endometrium. Trophinin, however, is expressed in the endometrium of the pig throughout the estrous cycle, higher expression levels were observed at some points of the luteal phase, as in humans. These findings suggest that regulation of trophinin gene expression in the pig is different from that in mice, but similar to that in humans. Furthermore, the present results suggest that the pig might be a suitable model for studying the physiological importance of trophinin in early pregnancy in humans. 相似文献
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Mohamed T Oikawa S Nakada K Kurosawa T Sawamukai Y Sato H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(7):821-824
A new method for catheterization of the portal and hepatic veins in cattle by means of the over-the-wire system was investigated to maintain more reliable long-term patency of catheters. Four cattle were used to evaluate the success rate, patency and safety of the procedure. The catheters, coated by urokinase were patent as long as they were in situ. In addition, the introducer was useful to prevent the catheter from being broken. No complications developed during the10 days after the procedure. Two cows were then euthanized. Post mortem findings were minimal. The results of the study reported here are promising, the benefits are significant and there is no apparent disadvantage to its use. 相似文献
30.
Katakura K Mimori T Furuya M Uezato H Nonaka S Okamoto M Gomez L EA Hashiguchi Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(5):649-653
PCR amplification and nucleotide sequencing of the mini-exon gene revealed that four strains isolated from a sloth (Choloepus hoffmanni), a squirrel (Sciurus granatensis) and two sandflies (Lutzomyia hartmanni) in Ecuador were indistinguishable from Endotrypanum monterogeii. Another strain isolated from Lu. hartmanni showed the high sequence similarity to E. schaudinni. Since three of these strains have been previously identified as Leishmania (Viannia) equatorensis, the results demonstrate that L. (V.) equatorensis is genetically closely related to the genus Endotrypanum. The present study also indicates that Endotrypanum species are distributed in arboreal animals and sandflies in Ecuador, and that mini-exon gene amplification is useful for epidemiological studies of Leishmania and Endotrypanum in the New World. 相似文献