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61.
62.
Poly(ADP-ribose): Historical perspective 总被引:2,自引:0,他引:2
63.
Masanao Matsui Bernard Stalla-Bourdillon 《Bioscience, biotechnology, and biochemistry》2013,77(10):1246-1249
The use of the Claisen type rearrangement previously studied by K. C. Brannock1) on some alkyl allyl esters leads in the present study from I, I-dimethyl-2-propenyl senecioate to a mixture of lavandulic acid 70% and iso-lavandulic acid 30%, 相似文献
64.
Iwai M Kanno H Senba I Nakaoka H Moritani T Horiuchi M 《Biochemical and biophysical research communications》2011,(1):403-126
The effect of the PPARγ agonistic action of an AT1 receptor blocker, irbesartan, on adipose tissue dysfunction was explored using atherosclerotic model mice. Adult male apolipoprotein E-deficient (ApoEKO) mice at 9 weeks of age were treated with a high-cholesterol diet (HCD) with or without irbesartan at a dose of 50 mg/kg/day for 4 weeks. The weight of epididymal and retroperitoneal adipose tissue was decreased by irbesartan without changing food intake or body weight. Treatment with irbesartan increased the expression of PPARγ in white adipose tissue and the DNA-binding activity of PPARγ in nuclear extract prepared from adipose tissue. The expression of adiponectin, leptin and insulin receptor was also increased by irbesartan. These results suggest that irbesartan induced activation of PPARγ and improved adipose tissue dysfunction including insulin resistance. 相似文献
65.
Sasakawa Y Kominami A Yamamoto K Nakaoka F Nakamura M Nakao M Abe M Fukuhama C Kagawa K 《Life sciences》2012,90(5-6):190-199
AimsWe investigated the effects of globin digest (GD) and its active ingredient Trp-Thr-Gln-Arg (WTQR) on galactosamine/lipopolysaccharide (GalN/LPS)-induced liver injury in imprinting control region (ICR) mice.Main methodsThe effects of WTQR and GD on the liver injury were examined by measuring the survival rate, serum aminotransferase activities, hepatic components, antioxidant enzyme activities, histopathological analysis, serum levels and hepatic gene expression of tumor necrosis factor-alpha (TNF-α), macrophage inflammatory protein-2 (MIP-2), and nitric oxide (NO) or inducible nitric oxide synthase (iNOS), and nuclear factor-kappa B (NF-κB) p65 content in GalN/LPS-treated ICR mice. RAW264 mouse macrophages were used to confirm the anti-inflammatory effects of WTQR and GD on the macrophages.Key findingsWTQR and GD increased the survival rate, suppressed the serum aminotransferase activities, serum levels and hepatic gene expression of TNF-α, MIP-2, and NO or iNOS, and nuclear NF-κB p65 content in GalN/LPS-treated mice; decreased the oxidized glutathione content, increased the superoxide dismutase activity, and decreased the histopathological grade values of the hepatocyte necrosis and lobular inflammation in GalN/LPS-injured liver; and suppressed the release levels and gene expression of TNF-α, MIP-2, and NO or iNOS, and nuclear NF-κB p65 content in LPS-stimulated RAW264 macrophages. WTQR and GD may improve the antioxidant defense system and inflammatory status in GalN/LPS-injured liver.SignificanceThese findings indicate that WTQR and GD have hepatoprotective effects on GalN/LPS-induced liver injury in ICR mice. 相似文献
66.
Akimi Wakui Masanao Sueyoshi Ayuma Shimokawabe Gaku Kudo Junko Morimoto Futoshi Nakamura 《Ecological Research》2017,32(2):183-191
Algific talus is a micro-scale habitat type where highland plants (subalpine and alpine species) are found, disjunct from their typical range, in lowland forests. On algific talus, cold airflows from the interstices between talus fragments create a local microclimate colder than surrounding forests. Despite of the widely-known occurrence of unique vegetation on algific talus, critical environmental factors determining the distribution of highland species in this habitat type are unclear. In order to reveal the environmental factors enabling highland species to inhabit algific talus, we investigated the vegetation and environments of 26 algific talus sites and four reference (non-algific talus) sites in Hokkaido, northern Japan. Several algific talus sites were dominated by highland species, while some algific talus sites and all non-algific talus sites were dominated by lowland species. Community analysis based on detrended correspondence analysis (DCA) and canonical corresponding analysis (CCA) revealed that the algific talus sites dominated by highland species had lower ground temperature, more acidic soil, larger canopy openness, and less diverse vegetation than the sites dominated by lowland species. Highland plants might be maintained under conditions stressful for lowland plants, resulting in less competitive situation. Generalized linear models (GLM), used to evaluate the response of individual highland species to environmental factors, revealed that preferable environmental conditions for highland plants are highly species specific. These results indicate that the maintenance of diverse environments is crucial for the conservation of the unique vegetation and local populations of highland species in algific talus areas. 相似文献
67.
Masahiro Tsujino Masakazu Hori Takehiro Okuda Masahiro Nakaoka Tomoko Yamamoto Takashi Noda 《Population Ecology》2010,52(1):171-180
It is well known that the similarity in species composition between two communities decays with the geographic distance that
separates them. It is thus likely that the similarity in the dynamics of two communities also decays with distance, because
the distance–decay relationship is fundamental in nature. However, the distance–decay relationships of community dynamics
have not yet been revealed. We used transition matrix models to evaluate distance–decay relationships of seasonal community
dynamics (from spring to summer) in rocky intertidal sessile assemblages along the Pacific coast of Japan between 31°N and
43°N. We evaluated the distance–decay relationships of whole-community dynamics and of three dynamics-related components—recruitment,
disturbance, and species interaction (competition and facilitation)—for communities separated by distances ranging from several
meters to thousands of kilometers. The similarity of the recruitment dynamics among communities declined rapidly with distance
within the fine spatial scale, but only moderately within larger scales. The similarity of the disturbance dynamics was independent
of distance, and the similarity of species interaction declined slightly with increasing distance. The similarity of whole-community
dynamics declined rapidly with distance at a fine spatial scale and moderately at larger scales. The fact that the distance–decay
relationship of whole-community dynamics was similar to that of recruitment may suggest that recruitment processes are the
most important determinant of spatial variability of community dynamics at our study sites during the study period. 相似文献
68.
Orientation of paramecium swimming in a static magnetic field: Dependence on membrane lipid fluidity
We studied the swimming orientation of the ciliated protozoan Paramecium aurelia in a static magnetic field (0.78 T). P. aurelia is a complex of species termed syngens, whose cell morphology appears similar on microscopic examination. In the magnetic field, the cells of some syngens gradually changed their swimming orientation so that they were swimming perpendicular or parallel to the magnetic field, although such sensitivity to magnetic fields differs between syngens. When the temperature of the cell suspension was raised, the magnetic sensitivity of the cells was decreased. On the other hand, when the cells were cultured beforehand at a high temperature, their magnetic sensitivity was increased. These results raise the possibility that membrane lipid fluidity, which is inversely proportional to the membrane lipid order, contributes to the magnetic orientation of syngens. In this study, measurements of membrane lipid fluidity obtained using fluorescence image analysis with the lipophilic dye, laurdan (6-lauroyl-2-dimethylaminonaphtalene), showed that the degree of membrane lipid fluidity was correlated with the differences in magnetic orientation between syngens. That is, the syngens with decreased membrane fluidity showed an increased degree of magnetic orientation. Therefore, the membrane lipid order is a key factor in the magnetic orientation of Paramecium swimming. 相似文献
69.
Takeshi Kitahara Keimei Fujimoto Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(8):1511-1514
The synthesis and biological activities of 2,2-dimethyl-3,3-dichlorocyclopropane carboxylic esters are descrived. 相似文献
70.
Toshio Atsumi Toshitsugu Fukumaru Tomoya Ogawa Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(11):2621-2626
A novel synthesis of N-acetyllincosamine derivatives (3) and (14) was accomplished. 相似文献