Water soluble elements in decomposing japanese cedar needle litter     

Masamichi Takahashi 《Soil Science and Plant Nutrition》2013,59(2):395-399

Many studies on the decrease in the contents of elements of decomposing litter have been carried out usually by applying the litter bag method in forest ecosystems. Release of elements from the litter, however, can be divided into three routes, that is, via liquid, solid, and gaseous phases, including leaching, fragmentation, and decomposer respiration, respectively. This study focused on water soluble elements in the decomposing needle litter of Japanese cedar (Cryptomeria japonica, D. Don) as a route of release via the liquid phase. Because rainfall leaches water soluble elements from decomposing litter on forest floor, the leaching process is important for the transport of elements from litter layers to soil horizons, which can affect the composition of soil solutions (Takahashi 1995). Moreover, nutrients in the leachate can be used for microbial and plant communities to control the dynamics of these communities. I investigated 1) the relationships between water soluble elements and the decomposition stages of the litter, and 2) variation in the contents of water soluble elements.  相似文献   

Gentian Kobu-sho-associated virus: a tentative, novel double-stranded RNA virus that is relevant to gentian Kobu-sho syndrome     

Kappei Kobayashi  Go Atsumi  Yasuya Iwadate  Reiko Tomita  Ken-ichi Chiba  Shiho Akasaka  Masahiro Nishihara  Hideyuki Takahashi  Naoto Yamaoka  Masamichi Nishiguchi  Ken-Taro Sekine 《Journal of General Plant Pathology》2013,79(1):56-63

A virus-like dsRNA of about 23 kbp was detected in gentian plants showing Kobu-sho syndrome including stunting, shortened internodes, and tumors on stems, nodes and roots. Nucleotide sequence analysis has suggested that this dsRNA is related to Pestivirus species but not to any other plant viruses. It was protected from externally added RNase, suggesting that the dsRNA is encapsidated. The dsRNA was co-extracted in a crude homogenate of glutaraldehyde-fixed tissue with the virus-like particles that have been associated previously with Kobu-sho syndrome in gentian (Usugi et al. Jpn J Phytopathol 76:21–24, 2010). The RNA sequence was detected in more than 99 % of Kobu-sho gentian individuals but in less than 20 % of apparently healthy gentian individuals from fields affected with Kobu-sho. Thus, we propose naming the virus Gentian Kobu-sho-associated virus.  相似文献   

Occurrence of blueberry mosaic associated virus in highbush blueberry trees with blueberry mosaic disease in Japan     

Masamichi Isogai  Yurie Matsuhashi  Kenshu Suzuki  Satoru Yashima  Manabu Watanabe  Nobuyuki Yoshikawa 《Journal of General Plant Pathology》2016,82(3):177-179

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Genomic RNA accumulation of gentian ovary ring-spot virus and raspberry bushy dwarf virus in pollen tubes     

Masamichi Isogai  Youhei Suzuki  Takanori Matsudaira  Nobuyuki Yoshikawa 《Journal of General Plant Pathology》2018,84(5):376-380

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Cauliflower mosaic virus Tav protein induces leaf chlorosis in transgenic tobacco through a host response to virulence function of Tav     

Sumyya Waliullah  Naomi Kosaka  Takashi Yaeno  Md. Emran Ali  Ken-Taro Sekine  Go Atsumi  Naoto Yamaoka  Masamichi Nishiguchi  Hideki Takahashi  Kappei Kobayashi 《Journal of General Plant Pathology》2015,81(4):261-270

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An Ultrastructural Study of the Sertoli Cell in the Water Buffalo (Bubalus bubalis)     

M. Kurohmaru    S. Yamashiro    T. I. Azmi  P. K. Basrur 《Anatomia, histologia, embryologia》1992,21(1):82-90

The ultrastructure of Sertoli cell in the water buffalo (Bubalus bubalis) was observed in a transmission electron microscope. The nucleus had homogeneous nucleoplasm, scarce heterochromatin and multivesicular nuclear body (MNB). The MNB was composed of numerous vesicles and ribosome-like dense structures. The vesicles varied in size and number and contained a sparse and flocculent substance. In the indentation of the nucleus, aggregates of ribosomes were frequently observed. In the apical and middle region of the cell, long mitochondria and microtubules were distributed parallel to the long axis of the cell. Non-laminated smooth ER and some ribosomes were also recognizable throughout this region. In the basal region, widely-distributed laminated smooth ER was characteristic. Microfilament bundles at ectoplasmic specialization were irregularly arranged. Frequently-emerged nodular processes occasionally separated from basal lamina and formed round structures within Sertoli cytoplasm. Although these characteristics of buffalo Sertoli cell were very similar to those of the bovine studied, the aggregate of ribosomes was more developed in the buffalo.  相似文献   

The fine structure of the blood-testis barrier in the boar   总被引：1，自引：0，他引：1  

F Yazama  T Nishida  M Kurohmaru  Y Hayashi 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1988,50(6):1259-1261

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Effect of placental soluble factors on growth and differentiation of mouse ectoplacental cone in vitro.     

M Azuma  Y Kanai  A Ogura  M Kurohmaru  Y Hayashi 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(5):839-845

The effect of soluble fractions derived from the placenta on the outgrowth and giant cell transformation of the ectoplacental cone (EPC) was investigated in vitro. EPCs taken from the fetal mice on day 7.5 post coitum (pc) were incubated with alpha-MEM-containing fetal calf serum (FCS) (FCS-alpha-MEM) for 24 hr. Then, the medium was exchanged with alpha-MEM alone, FCS-alpha-MEM, or alpha-MEM containing a crude extract from placental region on day 8.5, 10.5 or 12.5 pc (10 ml phosphate buffer/g placenta). Each EPC was continued to be incubated for 6 days, and the rate of EPC outgrowth and the number of trophoblastic giant cells (TGCs) were evaluated under a phase-contrast microscope. As a result, the administration of each placental extract significantly induced the cell spreading and TGC transformation of EPC as compared with the culture in alpha-MEM alone. The rate of cell-spreading rapidly increased on the 2nd day after incubation in the medium containing placental extracts. In particular, EPC outgrowth was more remarkable in the medium containing the 10.5-day placental extract than in the other media including FCS-containing medium. The number of transformed TGCs was also the largest in the 10.5-day medium among the groups examined. These results indicate that certain placental factors at mid-gestation, especially on day 10.5 pc, may facilitate the EPC differentiation.  相似文献   

Identification and quantification of the conjugated metabolites derived from orally administered hesperidin in rat plasma     

Matsumoto H  Ikoma Y  Sugiura M  Yano M  Hasegawa Y 《Journal of agricultural and food chemistry》2004,52(21):6653-6659

Hesperidin is a biologically effective flavonoid. Several studies have reported that dietary hesperidin was converted to conjugated metabolites, such as hesperetin-glucuronides and sulfoglucuronides, during absorption and metabolism. However, the chemical structures of the conjugated metabolites, especially the sites of glucuronidation and sulfoglucuronidation in plasma, were unconfirmed. Therefore, the concentrations of the metabolites conjugated at various sites in plasma could not be individually quantified. In the present study, we identified the chemical structures and concentrations of the major conjugated metabolites in rat plasma after oral administration of hesperidin. Two hesperetin-glucuronides were prepared and identified as hesperetin-7-O-beta-D-glucuronide and hesperetin-3'-O-beta-D-glucuronide. Using these authentic compounds, the concentrations of hesperetin-7-O-beta-D-glucuronide and hesperetin-3'-O-beta-D-glucuronide in rat plasma were individually determined by liquid chromatography-mass spectrometry. In rat plasma, hesperetin-glucuronides were primarily comprised of hesperetin-7-O-beta-D-glucuronide and hesperetin-3'-O-beta-D-glucuronide. The concentration of hesperetin-7-O-beta-D-glucuronide was slightly higher than that of hesperetin-3'-O-beta-D-glucuronide. Furthermore, not only hesperetin conjugates but also homoeriodictyol conjugates were observed in rat plasma. The present study is the first report elucidating the chemical structures and changes in individual concentrations in rat plasma of glucuronides derived from orally administered hesperidin.  相似文献   

Postnatal testicular development and actin appearance in the seminiferous epithelium of the Habu,Trimeresurus flavoviridis     

Masamichi Kurohmaru  Toshiyasu Matsui  Hitomi Igarashi  Shosaku Hattori  Yoshihiro Hayashi 《Anatomia, histologia, embryologia》2021,50(2):417-421

The postnatal testicular development and actin distribution in the seminiferous epithelium were examined by light microscopy, using the testes of the Habu (Trimeresurus flavoviridis; snake) from 0-year-old to 3-year-old. At 0-year-old (about 1 month after birth), the testis was quite small in size, and the seminiferous epithelium was composed of only Sertoli cells and large spermatogonia. Actin immunoreactivity was observed in the peritubular myoid cells, but could not be detected in the seminiferous epithelium. At 1-year-old (about 10 months after birth), the testicular size increased to a great degree. In the seminiferous epithelium, spermatocytes newly appeared. Actin could still not be detected in the seminiferous epithelium. At 2-year-old (about 1 year and 10 months after birth), the testes continued to develop in size. In the seminiferous epithelium, elongate spermatids and round spermatids were frequently seen, in addition to Sertoli cells, spermatogonia and spermatocytes. Thus, active spermatogenesis was clearly recognized at this age. Moreover, the actin distribution in the seminiferous epithelium was observed at the site between Sertoli cells and spermatids, as well as that at adult stage. The immunoreactivity of actin in the peritubular myoid cells gradually increased from 0-year-old to 2-year-old. Conclusively, it seems likely that spermatogenesis in the Habu initiates at 2-year-old, accompanying with the appearance of actin in the seminiferous epithelium.  相似文献