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M Koga T Uchida M Ueda M Shigeta T Yamamuro K Tamai T Suzuki T Saeki 《Nucleic acids symposium series》2000,(44):117-118
Achiral carbocyclic "DL-like" 5'-nor nucleosides have been synthesized and analyzed by the chiral capillary electrophoresis to elucidate the "D-like" monomers. 相似文献
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Shuichi Nagashima Hiroaki Yagyu Ryuichi Tozawa Fumiko Tazoe Manabu Takahashi Tetsuya Kitamine Daisuke Yamamuro Kent Sakai Motohiro Sekiya Hiroaki Okazaki Jun-ichi Osuga Akira Honda Shun Ishibashi 《Journal of lipid research》2015,56(5):998-1005
Squalene synthase (SS) catalyzes the biosynthesis of squalene, the first specific intermediate in the cholesterol biosynthetic pathway. To test the feasibility of lowering plasma cholesterol by inhibiting hepatic SS, we generated mice in which SS is specifically knocked out in the liver (L-SSKO) using Cre-loxP technology. Hepatic SS activity of L-SSKO mice was reduced by >90%. In addition, cholesterol biosynthesis in the liver slices was almost eliminated. Although the hepatic squalene contents were markedly reduced in L-SSKO mice, the hepatic contents of cholesterol and its precursors distal to squalene were indistinguishable from those of control mice, indicating the presence of sufficient centripetal flow of cholesterol and/or its precursors from the extrahepatic tissues. L-SSKO mice showed a transient liver dysfunction with moderate hepatomegaly presumably secondary to increased farnesol production. In a fed state, the plasma total cholesterol and triglyceride were significantly reduced in L-SSKO mice, primarily owing to reduced hepatic VLDL secretion. In a fasted state, the hypolipidemic effect was lost. mRNA expression of liver X receptor α target genes was reduced, while that of sterol-regulatory element binding protein 2 target genes was increased. In conclusion, liver-specific ablation of SS inhibits hepatic cholesterol biosynthesis and induces hypolipidemia without increasing significant mortality. 相似文献
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Hiroshi Kamiya Hitoshi Ohshiro Yu Tabayashi Yoshihiro Kano Koji Mishima Toshiyuki Godo Masumi Yamamuro Osamu Mitamura Yu Ishitobi 《Landscape and Ecological Engineering》2011,7(1):53-64
In situ phosphorus release rates in three contiguous shallow brackish lakes were calculated by considering the amount of water
inflow, changes in salinity and phosphorus stock, and loading from phosphorus inflow based on monthly data. The annual amount
of sedimental phosphorus relative to that of phosphorus inflow was different for each of the three water bodies: 16% for Lake
Shinji, 3% for the Honjo area, and −8% for Lake Nakaumi, as estimated in a 10-year period from January 1993 to December 2002.
During the warm season, the quantity of phosphorus released surpassed sedimentation in these three water bodies. The low annual
sedimentation ratio in Lake Nakaumi is related to a large seawater backflow resulting in phosphorus removal, in addition to
a stable stratified structure promoting phosphorus release from sediment due to oxygen depletion in the lower layer. In Lake
Nakaumi, field data shows that if dissolved oxygen at the sediment surface falls below 2.54 mg L−1, phosphorus release from the sediment begins to be accelerated. 相似文献
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Hirai Nobuhiro; Yamamuro Munehiro; Koshimizu Koichi; Shinozaki Masateru; Takimoto Atsushi 《Plant & cell physiology》1994,35(4):691-695
Extracts from the cotyledons of seedlings of Pharbitis nil strainViolet cultured at low temperature, which inducestheir flowering even in continuous light, with or without precedentexposure to high-intensity light, which shortens the periodof low temperature required for flowering, were analyzed byHPLC for substances correlating with the flower-inducing process.The content of two phenylpropanoids were found to increase duringthe low-temperature, and were identified as 3-O-feruloylquinicacid and dehydrodiconiferyl alcohol-13-O-ß-D-glucoside.The increase was more rapid in the cotyledons exposed to high-intensitylight before the low-temperature. This suggests that the accumulationof these compounds is correlated to the promotive effect ofhigh-intensity light on the flower-induction by low temperature. (Received March 7, 1994; Accepted April 2, 1994) 相似文献
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Relationship between river water quality and land use in a small river basin running through the urbanizing area of Central Japan 总被引:9,自引:0,他引:9
In this study, the relationship between water quality (as represented by major inorganic ion concentrations) and land use
characteristics is examined for a small river basin which runs through the urbanizing area of central Japan. Water samples
were taken from 24 sites at base flow and analyzed, and the proportions of the various land uses associated with the respective
drainage basins were calculated using a digital land-use map (scale: 1:25000). The electrical conductivity (EC) of the water
ranged from 84.5 to 600 μS cm−1. Ca2+ and Na+ were the major cations, accounting for 77% of all cations. Among the anions, HCO3
− was dominant (56%), followed by Cl− (24%), SO4
2− (13%) and NO3
− (7%). Applying principal component analysis to land use in the drainage basin yielded three principal components. The first
principal component expressed the degree of occupation by residential areas, the second indicated the degree of urban developing
area (i.e., fast-developing and industrial areas), and the third showed the degree of coverage with farmland and green space.
The residential area showed significant positive correlations with K+, Mg2+, Ca2+, NO3
−, HCO3
−, EC and TMI (total major ions). Urban developing area showed significant positive correlations with Ca2+, Cl−, HCO3
−, EC and TMI as well as weak negative correlations with NO3
− and SO4
2−. Industrial area showed weak positive correlations with Na+ and Cl− and a moderate negative correlation with NO3
−. Farmland showed significant positive correlations with NO3
− and SO4
2−; these ions are present due to fertilizers and the biological activity of plants. Forest area is inversely related to almost
all ions, indicating the need for this form of land use in order to maintain river water quality. 相似文献
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Motohiro Sekiya Daisuke Yamamuro Taichi Ohshiro Akira Honda Manabu Takahashi Masayoshi Kumagai Kent Sakai Shuichi Nagashima Hiroshi Tomoda Masaki Igarashi Hiroaki Okazaki Hiroaki Yagyu Jun-ichi Osuga Shun Ishibashi 《Journal of lipid research》2014,55(10):2082-2092
An excess of cholesterol and/or oxysterols induces apoptosis in macrophages, contributing to the development of advanced atherosclerotic lesions. In foam cells, these sterols are stored in esterified forms, which are hydrolyzed by two enzymes: neutral cholesterol ester hydrolase 1 (Nceh1) and hormone-sensitive lipase (Lipe). A deficiency in either enzyme leads to accelerated growth of atherosclerotic lesions in mice. However, it is poorly understood how the esterification and hydrolysis of sterols are linked to apoptosis. Remarkably, Nceh1-deficient thioglycollate-elicited peritoneal macrophages (TGEMs), but not Lipe-deficient TGEMs, were more susceptible to apoptosis induced by oxysterols, particularly 25-hydroxycholesterol (25-HC), and incubation with 25-HC caused massive accumulation of 25-HC ester in the endoplasmic reticulum (ER) due to its defective hydrolysis, thereby activating ER stress signaling such as induction of CCAAT/enhancer-binding protein-homologous protein (CHOP). These changes were nearly reversed by inhibition of ACAT1. In conclusion, deficiency of Nceh1 augments 25-HC-induced ER stress and subsequent apoptosis in TGEMs. In addition to reducing the cholesteryl ester content of foam cells, Nceh1 may protect against the pro-apoptotic effect of oxysterols and modulate the development of atherosclerosis. 相似文献
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Hiroya Tanaka Takao Yamamuro Manabu Matsumoto Yoshihiko Kotoura Chiaki Tanaka 《Prostaglandins & other lipid mediators》1985,30(1)
Effects of antineoplastic prostaglandins (PG), PGD2 and 9-deoxy-Δ9-PGD2, on colony formation of cloned Dunn osteosarcoma (TA 102), normal Swiss 3T3 and V-79 cell lines were evaluated. PGD2 significantly inhibited the colony formation of TA 102 cells in a dose-dependent manner at concentrations between 0.5 and 5 ug/ml. The IC50 value was calculated to be 0.72 ug/ml. A dose-dependent inhibition of TA 102 colony formation was also observed with 9-deoxy-Δ9-PGD2 between 0.01 to 1 ug/ml, the IC50 value being 0.22 ug/ml. These prostaglandins did not exert cytocidal effects in vitro on Swiss 3T3 cells at concentrations between 0.01 to 1 ug/ml. The two agents had no significant cytocidal effects on V-79 cells except for 9-deoxy-Δ9-PGD2 at a concentration of 5 ug/ml. These results suggest that PGD2 and 9-deoxy-Δ9-PGD2 are considered to have cytocidal activity on Dunn osteosarcoma cells in dosages which do not affect non-malignant cells. 相似文献
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Yutaka Yamamuro 《Experimental Animals》2005,54(4):369-372
This study investigated the lactating stage of rats to determine the effect on maternal behavior of a single exposure to general anesthetic. Lactating Wistar rats were treated with anesthetic doses of pentobarbital (PENT) or ketamine (KET) on day 3 or 9 of lactation, and their behavioral responses were evaluated during a 50-min nursing period, after a 4-h mother-pup separation, on day 12. Exposure to KET on day 9 led to a significantly longer latency to pup-retrieval than that of the control. Duration of pup-retrieval in mothers treated with KET on day 3 and 9 was significantly longer than in the control. Other components of maternal behavior did not differ between the groups. The present findings suggested that general anesthetics have an impact upon pup-retrieval activities, which indirectly represent maternal motivation. 相似文献