Leydig cell hyperplasia in an ENU-induced mutant mouse with germ cell depletion     

Khalaj M  Abbasi AR  Nishimura R  Akiyama K  Tsuji T  Noguchi J  Okuda K  Kunieda T 《The Journal of reproduction and development》2008,54(3):225-228

Repro22 is an N-ethyl-N-nitrosourea (ENU)-induced mutation in mice showing depletion of both male and female germ cells. In the present study, we investigated the male phenotypes of the mutant mouse at the adult stage. The repro22/repro22 homozygous mice showed reduced body weights as well as markedly reduced testis weights. Histological examination of the testes at 4 and 10 months of age showed no germ cells in the seminiferous tubules of the affected testis while a number of Sertoli cells were observed in the tubules. In addition to the germ cell depletion, the testes of the affected mouse contained expanded intertubular spaces that were filled by Leydig cell-like interstitial cells. These interstitial cells were confirmed to be Leydig cells by immunohistochmical staining using anti-3beta-HSD antibody. The estimated number of Leydig cells in the affected testes at 10 months of age increased approximately 2 fold compared with those of normal testes. Furthermore, the plasma testosterone levels of the affected mice at 10 months of age were significantly higher than those of the normal mice. These findings indicated that the repro22/repro22 mouse developed hyperplasia of Leydig cells that was presumably caused by the absence of germ cells in the seminiferous tubules.  相似文献   

Production efficiency and telomere length of the cloned pigs following serial somatic cell nuclear transfer   总被引：2，自引：0，他引：2  

Kurome M  Hisatomi H  Matsumoto S  Tomii R  Ueno S  Hiruma K  Saito H  Nakamura K  Okumura K  Matsumoto M  Kaji Y  Endo F  Nagashima H 《The Journal of reproduction and development》2008,54(4):254-258

The aim of the present study was to examine the production efficiency of cloned pigs by serial somatic cell nuclear transfer (SCNT) and to ascertain any changes in the telomere lengths of multiple generations of pigs. Using fetal fibroblasts as the starting nuclear donor cells, porcine salivary gland progenitor cells were collected from the resultant first-generation cloned pigs to successively produce second- and third-generation clones, with no significant differences in production efficiency, which ranged from 1.4% (2/140) to 3.3% (13/391) among the 3 generations. The average telomere lengths (terminal restriction fragment values) for the first, second and third generation clones were 16.3, 18.1 and 20.5 kb, respectively, and were comparable to those in age-matched controls. These findings suggest that third-generation cloned pigs can be produced by serial somatic cell cloning without compromising production efficiency and that the telomere lengths of cloned pigs from the first to third generations are normal.  相似文献   

拖拉机行驶路线的自动变更研究   总被引：3，自引：3，他引：0  

陈军  鸟巢谅 《农业工程学报》2005,21(1):83-86

为了实现拖拉机自动化作业的需要,本研究利用前馈控制和反馈控制相结合的控制方法,设计了拖拉机行驶路线自动变更的非线性反馈控制器。首先,利用非线性最优控制方法,设计了车辆进行行驶路线自动变更的基准轨迹;然后利用LQ最优控制技术,构造了车辆沿着基准轨迹进行行驶路线变更的反馈控制器。最后,利用设计的基准轨迹和反馈控制器进行了实车试验。试验表明,该控制方法具有良好的适应性,所设计的控制器具有良好的响应性和收敛性。  相似文献   

Augmentation and compatibility of Beauveria bassiana with pesticides against different growth stages of Bemisia tabaci (Gennadius); an in vitro and field approach     

David Wari  Ryo Okada  Motonori Takagi  Masato Yaguchi  Tetsuro Kashima  Takashi Ogawara 《Pest management science》2020,76(9):3236-3252

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Density and sound-speed contrasts,and target strength of Japanese sandeel <Emphasis Type="Italic">Ammodytes personatus</Emphasis>     

Hiroki Yasuma  Ryo Nakagawa  Takashi Yamakawa  Kazushi Miyashita  Ichiro Aoki 《Fisheries Science》2009,75(3):545-552

Sound-speed and density contrasts (h and g, respectively), important acoustic material properties, of Japanese sandeel Ammodytes personatus were measured to estimate theoretical target strength (TS). The measured sound-speed contrast of adult fish varied between 1.016 and 1.023 (mean 1.020), and showed temperature dependence. The measured density contrast differed significantly between juvenile and adult. The density contrast of juvenile varied between 1.017 and 1.024 (1.021), and that of adult varied between 1.026 and 1.038 (1.032). Using these results, TS at 38 and 120 kHz in the fishing season were estimated by an empirical sound scattering model. TS of an individual fish varied significantly with change of tilt angle. TS of near-dorsal aspect (TS_max) and tilt-averaged TS (TS_ave) differed by up to 7 dB. At both frequencies, two different TS_ave−length relationships (TS_ave = a log L + b) were obtained for adult and juvenile. The coefficients of log L of adult were close to 20, suggesting that backscattering strength was proportional to square of body length. These values were larger in juvenile (34.0 at 120 kHz, 56.5 at 38 kHz), suggesting that backscattering strength varied drastically with the cube or fifth power of body length.  相似文献   

Alpha-fetoprotein in serum and tumor tissues in dogs with hepatocellular carcinoma.   总被引：2，自引：0，他引：2  

Satoshi Kitao  Takatsugu Yamada  Takefumi Ishikawa  Hiroo Madarame  Mitsuru Furuichi  Sakurako Neo  Ryo Tsuchiya  Kosaku Kobayashi 《Journal of veterinary diagnostic investigation》2006,18(3):291-295

Serum alpha-fetoprotein (AFP) concentrations were measured before and after surgical removal of tumor masses in four dogs with hepatocellular carcinoma (HCC). Localization of AFP was also examined immunohistochemically in tumor tissues. In three cases, the serum AFP concentration was 10 to 20 times higher than that of normal dogs. One to two months after surgery, the serum AFP concentration had decreased to normal range. AFP was localized in the tumor tissues in these three cases. One case, which had a low serum AFP, did not show AFP localization in tumor tissue.  相似文献   

Progesterone stimulation by LH involves the phospholipase-C pathway in bovine luteal cells   总被引：2，自引：0，他引：2  

Nishimura R  Shibaya M  Skarzynski DJ  Okuda K 《The Journal of reproduction and development》2004,50(2):257-261

Luteinizing hormone (LH)-stimulated steroidogenesis in luteal cells is known to be mediated through the activation of cyclic AMP (cAMP)-dependent protein kinase, and to be also modulated by calcium-dependent mechanisms. In the present study, we tested the hypothesis that LH stimulates progesterone (P4) production in bovine luteal cells through activation of phospholipase (PL) C by using a cell culture system. Bovine mid-luteal cells (Days 8-12 of the estrous cycle) were cultured for 24 h and then exposed to a PLC inhibitor (U-73122; 10 microM) with or without LH (10 ng/ml) for 4 h. U-73122 blocked LH-stimulated P4 production without affecting cAMP accumulation. Moreover, exposure of luteal cells to PLC increased P4 production in a dose-dependent manner. These results support the hypothesis that the luteotropic action of LH in bovine luteal cells is mediated not only by activation of adenylate cyclase but also by activation of PLC.  相似文献   

Aboveground and belowground biomass in logged-over tropical rain forests under different soil conditions in Borneo     

Tanaka Kenzo  Ryo Furutani  Daisuke Hattori  Sota Tanaka  Katsutoshi Sakurai  Ikuo Ninomiya  Joseph Jawa Kendawang 《Journal of Forest Research》2015,20(1):197-205

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Relationship between formation of earlywood vessels and leaf phenology in two ring-porous hardwoods,Quercus serrata and Robinia pseudoacacia,in early spring     

Kayo Kudo  Koh Yasue  Yoshihiro Hosoo  Ryo Funada 《Journal of Wood Science》2015,61(5):455-464

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A Spontaneous Oligodendroglioma in the Lumbar Portion of the Spinal Cord in a Young BrlHan:WIST@Jcl (GALAS) Rat     

Shuji Takeda  Hiroyuki Asano  Ryo Ihara  Keiko Ogata  Masahiko Kushida 《Journal of toxicologic pathology》2014,27(2):143-146

Oligodendroglioma is a rare tumor originating from oligodendrocytes found mainly in the cerebrum in aged rats. Only a few reports have shown spontaneous occurrence of this tumor in the spinal cord, and no report has mentioned its occurrence in young rats. We encountered a case of spontaneous oligodendroglioma in the lumbar portion of the spinal cord in a young (9 weeks old) female BrlHan:WIST@Jcl (GALAS) rat. Here we report the detailed histopathological and immunohistochemical characteristics of this case. No clinical signs, no gross lesions at necropsy, and no specific changes in hematology or blood biochemistry were observed. The tumor was located in the dorsal funiculus in the lumbar portion of the spinal cord and widely spread to the dorsal root nerve. The neoplastic cells showed a sheet-like growth pattern and had small round nuclei, clear cytoplasm and distinct cell borders that resulted in a honeycomb pattern. No mitotic figures or other histological lesions were observed. The neoplastic cells were positively stained for Olig2 and PCNA. The present case was considered to be a low-grade oligodendroglioma based on the histological and immunohistochemical features. To our knowledge, our case is considered to be extremely rare and the first report in a young rat.  相似文献