Role of the hyaluronan receptor CD44 during porcine oocyte maturation     

Yokoo M  Shimizu T  Kimura N  Tunjung WA  Matsumoto H  Abe H  Sasada H  Rodriguez-Martinez H  Sato E 《The Journal of reproduction and development》2007,53(2):263-270

Previous our studies have shown that CD44, the principal receptor for hyaluronan, is present on cumulus cells during oocyte maturation. Although hyaluronan-CD44 interaction has been implicated in cumulus expansion and/or oocyte maturation, the full significance of CD44 remains unknown. The objective of the present study was to further investigate the role of CD44 in cumulus expansion and oocyte maturation in pigs. We demonstrate here in that CD44 has a key role in oocyte maturation but not in cumulus expansion. Previous studies have reported the physiological significance of cumulus expansion in oocyte maturation. However, our results suggest that cumulus expansion is a necessary condition for oocyte maturation, but that it is not sufficient on its own. Furthermore, western blot analysis demonstrated that the CD44 of the in vitro-matured cumulus-oocyte complexes (COCs) had a larger molecular weight and more terminal sialic acid, which has been proven to inhibit the hyaluronan-binding ability of the receptor, than the CD44 of the in vivo-matured COCs, indicating that the hyaluronan-CD44 interactions during in vitro maturation might be insufficient compared with those in vivo. The insufficient interactions of hyaluronan-CD44 during in vitro maturation may cause the inferior capacity of fertilization and development of oocytes matured in vitro.  相似文献   

Spindle formation and microtubule organization during first division in reconstructed rat embryos produced by somatic cell nuclear transfer     

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   

Comparison of the RNA polymerase I-, II- and III-dependent transcript levels between nuclear transfer and in vitro fertilized embryos at the blastocyst stage     

Suzuki T  Minami N  Kono T  Imai H 《The Journal of reproduction and development》2007,53(3):663-671

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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   

Silicon content in rice seedlings to protect rice blast fungus at the nursery stage   总被引：1，自引：0，他引：1  

Tsuyoshi Hayasaka  Hiroshi Fujii  Tsuneo Namai 《Journal of General Plant Pathology》2005,71(3):169-173

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   

Spatiotemporal pattern of EphA4 gene expression in developing quail limb buds     

Kenjiro ARISAWA  Shigenobu YAZAWA  June-ichi EGUCHI  Hiroshi KAGAMI  Tamao ONO 《Animal Science Journal》2005,76(1):65-71

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Identification of cDNA for the HSPA2, HSPA5 and HSPA8 orthologs of the heat shock protein 70 family from guinea fowl (Numida meleagris)     

Shigehisa IWAMOTO  Yohei KOIKE  Kazuyoshi HOSOMICHI  Hiromi HARA  Yutaka YOSHIDA  Hiroshi OGAWA  Kei HANZAWA 《Animal Science Journal》2005,76(5):519-524

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Antifungals produced by dinoflagellates—gambieric acids     

Hiroshi Nagai  Yuzuru Mikami  Takeshi Yasumoto 《Pest management science》1995,44(1):92-94

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A nematode, Orientostrongylus ezoensis, from brown rats in Sakai, Osaka Prefecture.     

M Yokota  M Hashimoto  T Matsui  N Oku  M Kida  K Ishikawa  H Miyagawa  T Ohnaka  K Nakajima 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(1):159-160

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Serological survey of influenza A virus infection in mink     

K Yagyu  R Yanagawa  Y Matsuura  H Fukushi  H Kida  H Noda 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1982,44(4):691-693

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