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991.
Hitoshi Suzuki Makoto Kawasaki Hideo Ohnishi Toshitaka Nakamura Yoichi Ueta 《Peptides》2009,30(9):1763-1770
Various kinds of stress cause neuroendocrine responses such as corticotropin-releasing hormone (CRH) or arginine vasopressin (AVP) release from parvocellular division of the paraventricular nucleus (PVN) and activation of the hypothalamo-pituitary adrenal (HPA) axis. We examined the effects of acute and chronic stress on the expression of the AVP-enhanced green fluorescent protein (eGFP) fusion gene in the hypothalamus, using chronic salt loading as an osmotic stimulation, intraperitoneal administration of lipopolysaccharide (LPS) as acute inflammatory stress and adjuvant arthritis (AA) as chronic inflammatory/nociceptive stress. Salt loading caused a marked increase in the eGFP gene expression and eGFP fluorescence in the supraoptic nucleus, magnocellular division of the PVN and internal layer of the median eminence (ME). Administration of LPS caused increased fluorescence in parvocellular division of the PVN and external layer of the ME. AA rats revealed an increased expression of the eGFP gene and eGFP fluorescence in both magnocellular and parvocellular divisions of the PVN and both internal and external layers of the ME. On the other hand, the levels of the CRH gene expression in parvocellular division of the PVN were significantly decreased as AA developed, though plasma concentrations of corticosterone were significantly increased. These results indicate that AVP-eGFP transgenic rats enable the detection of changes in AVP expression more easily than by using procedures such as immunohistochemistry. We propose that AVP-eGFP transgenic rats represent a useful animal model for further understanding of the physiology of AVP expression in the hypothalamo-pituitary system under various physiological conditions, including various kinds of stress. 相似文献
992.
993.
We measured seasonal changes in the gut clearance rate of three stonefly species in a stream. The rate declined with water
temperature. Based on the gut clearance rate obtained here, we estimated the half-reduction time of gut contents and consumption
rate of stoneflies on algae. Irrespective of stonefly species, the half-reduction time in winter (2 days) was twice as long
as that in summer (1 day). The areal consumption rates of stoneflies varied depending on species and season. These results
imply that the seasonal consumption impact of aquatic insects can be different, despite their daily ration being similar among
species. 相似文献
994.
995.
Natalie C. Ban 《Biodiversity and Conservation》2009,18(7):1829-1845
Marine protected areas (MPAs) can be an effective tool for marine biodiversity conservation, yet decision-makers usually have
limited and biased datasets with which to make decisions about where to locate MPAs. Using commonly available abiotic and
biotic datasets, I asked how many datasets are necessary to achieve robust patterns of conservation importance. I applied
a decision support tool for marine protected area design in two regions of British Columbia, Canada, and sequentially excluded
the datasets with the most limited geographic distribution. I found that the reserve selection method was robust to some missing
datasets. The removal of up to 15 of the most geographically limited datasets did not significantly change the geographic
patterns of the importance of areas for conservation. Indeed, including abiotic datasets plus at least 12 biotic datasets
resulted in a spatial pattern similar to including all available biotic datasets. It was best to combine abiotic and biotic
datasets in order to ensure habitats and species were represented. Patterns of clustering differed according to whether I
used one set alone or both combined. Biotic datasets served as better surrogates for abiotic datasets than vice versa, and
both represented more biodiversity features than randomly selected reserves. These results should provide encouragement to
decision-makers engaged in MPA planning with limited spatial data. 相似文献
996.
Yoshikazu Uto Tsuneaki Ogata Jun Harada Yohei Kiyotsuka Yuko Ueno Yuriko Miyazawa Hitoshi Kurata Tsuneo Deguchi Nobuaki Watanabe Toshiyuki Takagi Satoko Wakimoto Ryo Okuyama Manabu Abe Nobuya Kurikawa Sayako Kawamura Michiko Yamato Jun Osumi 《Bioorganic & medicinal chemistry letters》2009,19(15):4151-4158
A series of structurally novel stearoyl-CoA desaturase-1 (SCD-1) inhibitors has been identified by optimizing a hit from our corporate library. Preliminary structure–activity relationship (SAR) studies led to the discovery of the highly potent and orally bioavailable thiazole-based SCD-1 inhibitor, 3-(2-hydroxyethoxy)-4-methoxy-N-[5-(3-trifluoromethylbenzyl)thiazol-2-yl]benzamide (23a). 相似文献
997.
Masaki Goto Shunsuke Ishida Hitoshi Matsuki Shoji Kaneshina 《Chemistry and physics of lipids》2009,161(2):65-5831
The alignment of the sn-1 and sn-2 acyl chains at the terminal methyl ends generally produces significant influence on the thermodynamic properties of the bilayer phase transitions. We investigated the bilayer phase behavior of asymmetric phospholipids, myristoylpalmitoylphosphatidylcholine and palmitoylmyristoylphosphatidylcholine, by high-pressure light-transmittance and Prodan-fluorescence techniques and differential scanning calorimetry. Constructed temperature-pressure phase diagrams revealed that no stable phase can exist in the whole pressure range because of the formation of the most stable Lc phase. Nevertheless, the pretransition, the detection of which is severely hampered by the exceptionally prompt formation of the Lc phase, was successfully observed. Moreover, the effect of the total and difference of the sn-1 and sn-2 acyl chain lengths on minimal interdigitation pressure (MIP) was summarized in a MIP vs. chain-length inequivalence parameter plot, where the effect was proved to be classified in three zones depending on the alignment of both terminal methyl ends. 相似文献
998.
999.
Takuya Sakurai Tetsuya Izawa Jun-etsu Ogasawara Kazuhiko Imaizumi Hitoshi Ishida 《Biochemical and biophysical research communications》2009,379(2):605-1926
Increased oxidative stress in adipocytes causes dysregulated expression of inflammation-related adipokines. We have examined the effects of exercise training on oxidative stress in rat white adipose tissue (WAT), especially focusing on inflammation-related adipokines. The levels of lipid peroxidation in WAT of exercise-trained (TR) rats were lower than those in control (C) rats. The content of manganese-containing superoxide dismutase in WAT of TR rats was increased as compared with those in C rats. In contrast, the expression of the NADPH oxidase NOX2 protein in WAT was downregulated by exercise training. Moreover, the levels of inflammation-related adipokines, such as tumor necrosis factor-α and monocyte chemoattractant protein-1, in WAT of TR rats were lower than those in C rats. The effects of exercise training were more remarkable in visceral WAT than in subcutaneous. These results suggest that exercise training decreases the expression of inflammation-related adipokines by reducing oxidative stress in WAT. 相似文献
1000.