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111.
We examined the effects of radiation on decreases in osteoclast numbers after regional irradiation of rats with carbon ions and gamma rays. Male Wistar rats were subjected to hind-leg irradiation with carbon ions (290 MeV/u) or gamma rays at doses of 15, 22.5, or 30 Gy. The effects of carbon ions and gamma rays on osteoclasts were studied using histologic and morphometric methods. At doses of 15 Gy and 22.5 Gy, osteoclast numbers increased transiently until day 5 after irradiation and then decreased rapidly in both the carbon ion and gamma ray irradiation groups. The carbon ion group showed reduced osteoclast size compared with the gamma ray group. Carbon ion irradiation had a more marked effect on osteoclast activity, and suppressed maturation to a greater extent than gamma irradiation. These observations suggest that carbon ion irradiation induces differential modulation of osteoclast growth factor expression. 相似文献
112.
A new synthetic methodology for aldoses and aldonitols was developed in which two stereospecific epoxide-opening reactions with double inversion of the configuration, i.e., the ring-opening reaction of epoxy sulfides with phenylboronic acid and the stereospecific interconversion of trans- and cis-epoxy sulfides, were designed as the key steps. The synthetic potential of the new methodology was exemplified by the highly stereoselective synthesis of two pentose-derived sugars, arabitol and adonitol (ribitol). 相似文献
113.
We studied the synergistic effects of Japanese green tea extract (JGTE) and levofloxacin (LVFX) against enterohemorrhagic
Escherichia coli (EHEC) infection in a gnotobiotic mouse model. Mice fed on JGTE conferred a significant degree of protection against an oral
challenge with EHEC. Complete elimination of the bacteria from the mice, was however, difficult. The combination of JGTE and
LVFX increased the survival rate and reduced damage to target organs. Thus, dietary supplementation with JGTE improved the
therapeutic effects of antibiotic treatment.
Received: 28 July 2000 / Accepted: 19 September 2000 相似文献
114.
115.
Production of the Carotenoids Lycopene, β-Carotene, and Astaxanthin in the Food Yeast Candida utilis
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Yutaka Miura Keiji Kondo Toshiko Saito Hiroshi Shimada Paul D. Fraser Norihiko Misawa 《Applied microbiology》1998,64(4):1226-1229
The food-grade yeast Candida utilis has been engineered to confer a novel biosynthetic pathway for the production of carotenoids such as lycopene, β-carotene, and astaxanthin. The exogenous carotenoid biosynthesis genes were derived from the epiphytic bacterium Erwinia uredovora and the marine bacterium Agrobacterium aurantiacum. The carotenoid biosynthesis genes were individually modified based on the codon usage of the C. utilis glyceraldehyde 3-phosphate dehydrogenase gene and expressed in C. utilis under the control of the constitutive promoters and terminators derived from C. utilis. The resultant yeast strains accumulated lycopene, β-carotene, and astaxanthin in the cells at 1.1, 0.4, and 0.4 mg per g (dry weight) of cells, respectively. This was considered to be a result of the carbon flow into ergosterol biosynthesis being partially redirected to the nonendogenous pathway for carotenoid production. 相似文献
116.
Matoh Toru; Takasaki Miki; Takabe Keiji; Kobayashi Masaru 《Plant & cell physiology》1998,39(5):483-491
A polyclonal antibody against a borate-RG-II complex is raisedin rabbits. The antibody recognized RG-II exclusively in cellwall polysaccharides. Immunocytochemical studies demonstratedthat the epitope is ubiquitous in cell walls of all the cellsin radish and rice roots, cultured tobacco cells, red cloverroot nodules, and lily growing pollen tubes. The label was denserin proximal to plasma membrane, and not detected in middle lamella,suggesting that borate may cross-link newly secreted pecticpolysaccharides at the membrane-cell wall interface. (Received October 13, 1997; Accepted February 16, 1998) 相似文献
117.
1. Human medulloblastoma (ONS-76), a central nervous system (CNS)-derived undifferentiated cell line, was found to possess glial characteristics as defined by responses in the interferon (IFN) system; ONS-76 cells produced as much IFN- as human fibroblast and glioma cells by viral infection and poly(I):poly(C) induction.2. Major histocompatibility complex (MHC) class I antigens were also induced under IFN- stimulation. ONS-76 cells expressed neurofilament protein, as shown by Northern blot analysis, and morphological differentiation was induced by dibutyryl cyclic AMP (dcAMP).3. Expression of IFN- and MHC class I antigens was suppressed in ONS-76 cells during the dcAMP-induced differentiation.4. These results showed that ONS-76 cells possessed a glial properly in IFN system responses and a neuronal property in cytoskeleton protein, suggesting that the precursors of medulloblastoma may be characterized as bipotent neuronal and glial progenitors in CNS. 相似文献
118.
Munetaka Ozeki Adeeb Salah Wulamujiang Aini Keiji Tamaki Hironori Haga Aya Miyagawa-Hayashino 《PloS one》2015,10(8)
The biological significance of STK17A, a serine/threonine kinase, in the liver is not known. We analyzed STK17A expression in HepG2 cells and human liver tissue. Accordingly, we investigated whether STK17A could help in identifying earlier changes during the evolution of chronic rejection (CR) after liver transplantation. RT-PCR and immunofluorescence were used to analyze STK17A expression in HepG2 cells. Antibody microarray was performed using human liver samples from CR and healthy donors. Immunohistochemistry was used to verify the clinical utility of STK17A on sequential biopsies for the subsequent development of CR. A novel short isoform of STK17A was found in HepG2 cells. STK17A was localized in the nuclei and bile canaliculi in HepG2 cells and human livers. Microarray of STK17A revealed its decrease in failed liver allografts by CR. During the evolution of CR, the staining pattern of bile canalicular STK17A gradually changed from diffuse linear to focal intermittent. The focal intermittent staining pattern was observed before the definite diagnosis of CR. In conclusion, the present study was the first to find localization of STK17A in normal bile canaliculi. Abnormal expression and localization of STK17A were associated with CR of liver allografts since the early stage of the rejection process. 相似文献
119.
Kazuyuki Wakabayashi Kouichi Soga Takayuki Hoson Toshihisa Kotake Takashi Yamazaki Akira Higashibata Noriaki Ishioka Toru Shimazu Keiji Fukui Ikuko Osada Haruo Kasahara Motoshi Kamada 《PloS one》2015,10(9)
Network structures created by hydroxycinnamate cross-links within the cell wall architecture of gramineous plants make the cell wall resistant to the gravitational force of the earth. In this study, the effects of microgravity on the formation of cell wall-bound hydroxycinnamates were examined using etiolated rice shoots simultaneously grown under artificial 1 g and microgravity conditions in the Cell Biology Experiment Facility on the International Space Station. Measurement of the mechanical properties of cell walls showed that shoot cell walls became stiff during the growth period and that microgravity suppressed this stiffening. Amounts of cell wall polysaccharides, cell wall-bound phenolic acids, and lignin in rice shoots increased as the shoot grew. Microgravity did not influence changes in the amounts of cell wall polysaccharides or phenolic acid monomers such as ferulic acid (FA) and p-coumaric acid, but it suppressed increases in diferulic acid (DFA) isomers and lignin. Activities of the enzymes phenylalanine ammonia-lyase (PAL) and cell wall-bound peroxidase (CW-PRX) in shoots also increased as the shoot grew. PAL activity in microgravity-grown shoots was almost comparable to that in artificial 1 g-grown shoots, while CW-PRX activity increased less in microgravity-grown shoots than in artificial 1 g-grown shoots. Furthermore, the increases in expression levels of some class III peroxidase genes were reduced under microgravity conditions. These results suggest that a microgravity environment modifies the expression levels of certain class III peroxidase genes in rice shoots, that the resultant reduction of CW-PRX activity may be involved in suppressing DFA formation and lignin polymerization, and that this suppression may cause a decrease in cross-linkages within the cell wall architecture. The reduction in intra-network structures may contribute to keeping the cell wall loose under microgravity conditions. 相似文献
120.
Yoko Maruyama Yu-Shin Sou Shun Kageyama Takao Takahashi Takashi Ueno Keiji Tanaka Masaaki Komatsu Yoshinobu Ichimura 《Biochemical and biophysical research communications》2014
Autophagy is a unique intracellular protein degradation system accompanied by autophagosome formation. Besides its important role through bulk degradation in supplying nutrients, this system has an ability to degrade certain proteins, organelles, and invading bacteria selectively to maintain cellular homeostasis. In yeasts, Atg8p plays key roles in both autophagosome formation and selective autophagy based on its membrane fusion property and interaction with autophagy adaptors/specific substrates. In contrast to the single Atg8p in yeast, mammals have 6 homologs of Atg8p comprising LC3 and GABARAP families. However, it is not clear these two families have different or similar functions. The aim of this study was to determine the separate roles of LC3 and GABARAP families in basal/constitutive and/or selective autophagy. While the combined knockdown of LC3 and GABARAP families caused a defect in long-lived protein degradation through lysosomes, knockdown of each had no effect on the degradation. Meanwhile, knockdown of LC3B but not GABARAPs resulted in significant accumulation of p62/Sqstm1, one of the selective substrate for autophagy. Our results suggest that while mammalian Atg8 homologs are functionally redundant with regard to autophagosome formation, selective autophagy is regulated by specific Atg8 homologs. 相似文献