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991.
Ikuko Ueno Masaru Sekijima Mikio Hoshino Hiroaki Ohya-Nishiguchi Yoshio Ueno 《Free radical research》1995,23(1):41-50
Luteoskyrin is a hepatotoxic and hepatocarcinogenic bisdihydroanthraquinone produced by Penicillium islandicum Sopp. By observing the EPR spectra of DMPO-spin adducts and luteoskyrin semiquinone radical, we investigated in vitro whether luteoskyrin is reduced to its semiquinone radical leading to the generation of active oxygen species in redox systems catalyzed by NADPH-dependent cytochrome reductases of the liver. We found (1) the formation of luteoskyrin semiquinone radical in the NADPH-cytochrome P-450 reductase system under anaerobic conditions, (2) the generation of O- in the systems composed of luteoskyrin, NAD(P)H, and either rat liver microsomal NADPH-cytochrome P-450 reductase or submitochondrial particles and (3) dicoumarol showed no effect on the O- generation in the case of submitochondrial particles. From these results we proposed that luteoskyrin liver injuries are induced by the active oxygen species generated in the process of autoxidation of luteoskyrin semiquinone radical which is produced in the one-electron redox systems catalyzed by the liver NAD(P)H-dependent cytochrome reductases. 相似文献
992.
Masayuki Nakamichi Yasuo Kojima Naosuke Itoigawa Shinji Imakawa Shoji Machida 《Primates; journal of primatology》1995,36(3):385-396
This report documents the social interactions among adult Japanese macaques in a free-ranging troop before and after the death
of the alpha male, who died at 28 years of age after occupying his rank position for 17 years. The alpha male’s physical condition
had deteriorated due to his extreme age for several months before his death. However, he maintained his alpha position. When
he was attacked by the second-ranking adult male, he was rescued by the alpha female. Thereafter, whenever the second-ranking
male approached him, the alpha male screamed for the alpha female’s support. The number of adult females to whom the alpha
male maintained proximity during his last four months was similar to that during the same period of the previous year. Prior
to his death, the alpha male was observed in close proximity to the alpha female much more frequently than was the second-ranking
male. These results indicate that the alpha male maintained his position by depending on female support and particularly that
of the alpha female. 相似文献
993.
Morphological changes of female reproductive organs of Japanese monkeys with reproductive conditions
Macroscopic and histological changes were examined on the female reproductive organs of Japanese monkeys (Macaca fuscata) with varying reproductive status in enclosed and provisioned troops. The weight and size of reproductive organs are described.
The size of uterus declined in 2–3 months after parturition. The number of parturition was roughly estimated by degrees of
sclerosis in myometrial vessels. The nipple length of parous animals was longer than that of nulliparous ones. The bilateral
difference in the length (more than 3 mm) between nipples indicated the experience of nursing. Interpreting ovaries on the
basis of macroscopic examination alone was less precise. The present results suggested that the female sexual maturity and
the experience of nursing can be estimated by the measurement of reproductive organs in the Japanese monkey. 相似文献
994.
995.
Spawning behavior and haremic mating system in the corallivorous butterflyfish,Chaetodon trifascialis, at Kuroshima Island, Okinawa 总被引:1,自引:1,他引:0
Territorial and spawning behavior ofChaetodon trifascialis were investigated on a small patch of reef at Kuroshima Island, Okinawa, Japan. Three males and 8 females inhabited the reef,
each individual defending a territory against conspecifics of the same sex. Each male territory included 2 or 3 female territories.
In the daytime, each male frequently visited the females living in its territory. At dusk in the full or new moon periods,
courtship began within the female territories, pair spawning subsequently occurring within or near those territories. When
a male actively courted a female in the territory of a second male, the latter male immediately chased off the intruder. Thus,
mating occurred only between a male and females living in former's territory. This is the first report of a haremic mating
system among butterflyfishes (Chaetodontidae). 相似文献
996.
Shinji Yabuta 《Ichthyological Research》1997,44(2-3):177-182
Spawning and related behavior of a monogamous butterflyfish,Chaetodon trifasciatus, were observed at Kuroshima Island, Okinawa, Japan. Each heterosexual pair defended a feeding territory in the daytime. Spawning
occurred at dusk on the days around full or new moon in the daytime. Spawning occurred at dusk on the days around full or
new moon in the vicinity of offshore tidal currents. Spawning migration to such sites occurred in pairs, the feeding territories
of which were located in areas of inshore currents. In the evening each pair established a small temporary territory, which
they spawned adjacent to and slept within until the next morning. The distribution of sleeping sites as well as tidal current
directions may determine the spawning sites of this butterflyfish. 相似文献
997.
Daisei Miyamoto Takao Ueno Sachiko Takashima Kazuhide Ohta Toshio Miyawaki Takashi Suzuki Yasuo Suzuki 《Glycoconjugate journal》1997,14(3):379-388
A new monoclonal antibody (TU-1) directed against the Galα1-4Galβ1-4Glc residue of the Gb3Cer/CD77 antigen was prepared by
the hybridoma technique following immunization of mice with an emulsion composed of monophosphoryl lipid A, trehalose dimycolate,
and Gb3Cer isolated from porcine erythrocytes. TU-1 showed reactivity towards Gb3Cer and lyso-Gb3Cer (Galα1-4Galβ1-4Glcβ1-1′Sph),
although the reactivity towards lyso-Gb3Cer was about 10-fold lower than that to Gb3Cer. But it did not react with other structurally-related
glycolipids, such as LacCer (Galβ1-4Glcβ1-1′Cer), Gg3Cer, Gg4Cer, Gb4Cer (GalNAcβ1-3Galα1-4Galβ1-4Glcβ1-1′Cer), galactosylparagloboside
(Galα1-3Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer), sulfatide (HSO3-3Galβ1-1′Cer), other gangliosides (GM3, GM2, GM1a, GD1a and
GT1b), or P1 antigen (Galα1-4Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer) among neutral glycolipids prepared from P1 phenotype red
blood cells. Furthermore, TU-1 reacted with viable lymphoma cells, such as human Burkitt lymphoma cell line, Daudi, and Epstein-Barr
virus (EBV)-transformed B cells by the immunofluorescence method, and also with germinal centre B cells in human tonsil and
vessel endothelial cells in human thymus histochemically. These results indicate that TU-1 is a monoclonal antibody directed
against Gb3Cer/CD77 antigen and can be utilized as a diagnostic reagent for Burkitt's lymphoma and also for detection of the
blood group Pk antigen in glycolipid extracts of erythrocytes. Abbreviations: ATL, adult T-cell leukaemia; BSA, bovine serum
albumin; Cer, ceramide; DPPC, L-α-dipalmitoylphosphatidylcholine; EBV, Epstein-Barr virus; FCS, fetal calf serum; GalCer,
Galβ1-1′Cer; GlcCer, Glcβ1-1′Cer; LacCer, Galβ1-4Glcβ1-1′Cer; Gb3Cer, Galα1-4Galβ1-4Glcβ1-1′Cer; Iyso-Gb3Cer, Galα1-4Galβ1-4Glc1-1′Sph;
Gb4Cer, GalNAcβ1-3Galα1-4Galβ1-4Glc1-1′Cer; galactosylparagloboside, Galα1-3Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer; Gg3Cer, GalNAcβ1-4Galβ1-4Glcβ1-1′Cer;
Gg4Cer, Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1′Cer; GM3, Neu5Acα2-3Galβ1-4Glcβ1-1′Cer; GM2, GalNAcβ1-4(Neu5Acα2-3) Galβ1-4Glcβ1-1′Cer;
GM1a, Galβ1-3GalNAcβ1-4(Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GD1a, Neu5Acα2-3Galβ1-3GalNAcβ1-4(Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GD1b,
Galβ1-3GalNAcβ1-4(Neu5Acα2-8Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GT1b, Neu5Acα2-3Galβ1-3GalNAcβ1-4(Neu5Acα2-8Neu5Acα2-3) Galβ1-4Glcβ1-1′Cer;
HRP, horseradish peroxidase; LDH, lactate dehydrogenase; MAb, monoclonal antibody; MPL, monophosphoryl lipid A; P1 antigen,
Galα1-4Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer; PVP, polyvinylpyrolidone; Sph, sphingosine; sulfatide, HSO3-Galβ1-1′Cer; TDM,
trehalose dimycolate; TLC, thin-layer chromatography
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
998.
Chiharu Morita Kimisachi Tsuchiya Hiroshi Ueno Yasukazu Muramatsu Akiko Kojimahara Hitoshi Suzuki Nobumoto Miyashita Kazuo Moriwaki Mei-Lei Jin Xiang-Lin Wu Feng-Shan Wang 《Microbiology and immunology》1996,40(4):313-315
Serum samples from 337 wild house mice (Mus musculus) from 35 sites in China, collected in 1992 and 1993, were examined for antibodies against lymphocytic choriomeningitis virus (LCMV). Ten samples from eight sites were found to contain such antibodies. Six of the eight positive sites were located in the territory of M. m. gansuensis. One of the other two sites was located in the territory of M. m. castaneus in southern China and the other site was in a habitat of M. m. castaneus which had invaded into the western end of the territory of M. m. homourus. It seems likely that LCMV is distributed in the territories of M. m. gansuensis and M. m. castaneus in China. This is the first report of detection of these antibodies in wild house mice in China and specifically in the territories of M. m. gansuensis and M. m. castaneus. 相似文献
999.
H. Okuyama Akio Ueno Daisuke Enari Naoki Morita Teruo Kusano 《Archives of microbiology》1997,169(1):29-35
A 9-hexadecenoic acid cis-trans isomerase (9-isomerase) that catalyzed the cis-to-trans isomerization of the double bond of free 9-cis-hexadecenoic acid [16:1(9c)] was purified to homogeneity from an extract of Pseudomonas sp. strain E-3 and characterized. Electrophoresis of the purified enzyme on both incompletely denaturing and denaturing polyacrylamide
gels yielded a single band of a protein with a molecular mass of 80 kDa, suggesting that the isomerase is a monomeric protein
of 80 kDa. The 9-isomerase, assayed with 16:1(9c) as a substrate, had a specific activity of 22.8 μmol h–1 (mg protein)–1 and a K
m of 117.6 mM. The optimal pH and temperature for catalysis were approximately pH 7–8 and 30° C, respectively. The 9-isomerase
catalyzed the cis-to-trans conversion of a double bond at positions 9, 10, or 11, but not that of a double bond at position 6 or 7 of cis-mono-unsaturated fatty acids with carbon chain lengths of 14, 15, 16, and 17. Octadecenoic acids with a double bond at position
9 or 11 were not susceptible to isomerization. These results suggest that 9-isomerase has a strict specificity for both the
position of the double bond and the chain length of the fatty acid. The enzyme catalyzed the cis-to-trans isomerization of fatty acids in a free form, and in the presence of a membrane fraction it was also able to isomerize 16:1(9c)
esterified to phosphatidylethanolamine. The 9-isomerase was strongly inhibited by catecholic antioxidants such as α-tocopherol
and nordihydroguaiaretic acid, but was not inhibited by 1,10-phenanthroline or EDTA or under anoxic conditions. Based on these
results, the possible mechanism of catalysis by this enzyme is discussed.
Received: 21 May 1997 / Accepted: 5 September 1997 相似文献
1000.
Tsuyoshi Yanase Yasukazu Muramatsu Hiroshi Ueno Chiharu Morita 《Microbiology and immunology》1997,41(2):73-75
The prevalence and seasonal variations of infection by Coxiella burnetii in cattle were investigated seroepidemiologically on a farm in Hokkaido, Japan, by an immunofluorescent antibody test. A total of 364 serum samples from 28 cows were collected from August 1993 to October 1995 in two barns on the farm. It was found that the number of antibody-positive cows and their antibody titers were significantly elevated in winter and decreased in summer. In addition, antibodies were detectable in seroconverted cows for about five months. 相似文献