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991.
Sayaka Ohrui Naoshi Yamamoto Tsuyoshi Saitoh Noriki Kutsumura Yasuyuki Nagumo Yoko Irukayama-Tomobe Yasuhiro Ogawa Yukiko Ishikawa Yurie Watanabe Daichi Hayakawa Hiroaki Gouda Masashi Yanagisawa Hiroshi Nagase 《Bioorganic & medicinal chemistry letters》2018,28(4):774-777
The 14-dehydration- and 14-H derivatives of the orexin 1 receptor (OX1R) antagonist YNT-707 (2) were synthesized. The obtained derivatives showed higher affinities for OX1R than the corresponding 14-hydroxy derivatives. The conformational analysis suggested that the 17-sulfonamide groups in the derivatives without the 14-hydroxy group have a greater tendency to be oriented toward the upper side of the D-ring compared with the 14-hydroxy derivatives. Additionally, the 14-dehydration-derivative with 6α-amide side chain showed significantly higher affinity than the 14-hydroxy derivative, while the corresponding 14-H derivative showed only slightly higher affinity. Thus, the 14-hydroxy group strongly affects the affinity of the antagonist for the OX1R. 相似文献
992.
Antonio Villalobo Hiroaki Ishida Hans J. Vogel Martin W. Berchtold 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2018,1865(3):507-521
Calmodulin (CaM) is a universal regulator for a huge number of proteins in all eukaryotic cells. Best known is its function as a calcium-dependent modulator of the activity of enzymes, such as protein kinases and phosphatases, as well as other signaling proteins including membrane receptors, channels and structural proteins. However, less well known is the fact that CaM can also function as a Ca2 +-dependent adaptor protein, either by bridging between different domains of the same protein or by linking two identical or different target proteins together. These activities are possible due to the fact that CaM contains two independently-folded Ca2 + binding lobes that are able to interact differentially and to some degree separately with targets proteins. In addition, CaM can interact with and regulates several proteins that function exclusively as adaptors. This review provides an overview over our present knowledge concerning the structural and functional aspects of the role of CaM as an adaptor protein and as a regulator of known adaptor/scaffold proteins. 相似文献
993.
Background
The purpose of this study was to determing which psychological traits of Japanese type 2 diabetes patients would provide reliability and validity to the Japanese version of the Acceptance and Action Diabetes Questionnaire (AADQ-J).Methods
Various questionnaires were administered to type 2 diabetes patients who were registered on the database of the research service provider; data from a total of 600 patients (mean?±?SD age was 57.50?±?9.87 years, female 21.83%) were analyzed.Results
Three items were excluded because of psychometric concerns related to the original 11-item AADQ. Confirmation factor analyses revealed that the eight-item version demonstrated the best indicators of a goodness of fit. The questionnaire showed adequate internal consistency. The questionnaire demonstrated high measurement accuracy in broad trait values by the test information function of Item Response Theory. The questionnaire showed stronger positive correlations with self-care activities and HbA1c than with diabetes distress and depressive mood.Conclusions
The eight-item Japanese version of AADQ has reliability and validity for type 2 diabetes patients.994.
Naoki Kodama Yoshiya Moriguchi Aya Takeda Motonari Maeda Tetsuya Ando Hiroe Kikuchi Motoharu Gondo Hiroaki Adachi Gen Komaki 《BioPsychoSocial medicine》2018,12(1):15
Background
The neural mechanisms underlying body dissatisfaction and emotional problems evoked by social comparisons in patients with anorexia nervosa (AN) are currently unclear. Here, we elucidate patterns of brain activation among recovered patients with AN (recAN) during body comparison and weight estimation with functional magnetic resonance imaging (fMRI).Methods
We used fMRI to examine 12 patients with recAN and 13 healthy controls while they performed body comparison and weight estimation tasks with images of underweight, healthy weight, and overweight female bodies. In the body comparison task, participants rated their anxiety levels while comparing their own body with the presented image. In the weight estimation task, participants estimated the weight of the body in the presented image. We used between-group region of interest (ROI) analyses of the blood oxygen level dependent (BOLD) signal to analyze differences in brain activation patterns between the groups. In addition, to investigate activation outside predetermined ROIs, we performed an exploratory whole-brain analysis to identify group differences.Results
We found that, compared to healthy controls, patients with recAN exhibited significantly greater activation in the pregenual anterior cingulate cortex (pgACC) when comparing their own bodies with images of underweight female bodies. In addition, we found that, compared with healthy controls, patients with recAN exhibited significantly smaller activation in the middle temporal gyrus corresponding to the extrastriate body area (EBA) when comparing their own bodies, irrespective of weight, during self-other comparisons of body shape.Conclusions
Our findings from a group of patients with recAN suggest that the pathology of AN may lie in an inability to regulate negative affect in response to body images via pgACC activation during body comparisons. The findings also suggest that altered body image processing in the brain persists even after recovery from AN.995.
Osamu Shida Hiroaki Takagi Kiyoshi Kadowaki Hiroshi Yano Kazuo Komagata 《Antonie van Leeuwenhoek》1996,70(1):31-39
Ninety strains of eleven Bacillus species in the Bacillus brevis group and the Bacillus aneurinolyticus group were compared with the electrophoretic whole-cell protein pattern. The strains were separated into two clusters at the similarity of 55%. One cluster (cluster 1) was consisted of strains from the B. brevis group, and another cluster (cluster 2) was composed of strains from the B. aneurinolyticus group. The cluster 1 was separated into eight subclusters. Out of eight subclusters, seven subclusters contain strains from B. brevis, B. laterosporus, B. agri, B. reuszeri, B. choshinensis, B. formosus, and B. borstelensis. Another subcluster was further separated into two related clusters, which corresponded to B. centrosporus and B. parabrevis, and they were fused at the similarity of 76%. Cluster 2 was separated into two subclusters, which corresponded to B. aneurinolyticus and B. migulanus. The above eleven species showed characteristic patterns distinct from one another, and this correlated well with the published DNA relatedness data. The comparison of the electrophoretic whole-cell protein pattern proved to be useful for evaluation of taxonomic relationships among these taxa. 相似文献
996.
997.
Gorou Horiguchi Hirotaka Iwakawa Hiroaki Kodama Naoto Kawakami Mitsuo Nishimura Koh Iba 《Physiologia plantarum》1996,96(2):275-283
The leaves of monocotyledonous plants create a developmental sequence of cells and plastids from the base to the apical portion. We investigated fatty-acid and lipid compositions in successive leaf sections of light- and dark-grown wheat (Triticum aestivum L. cv. Chihoku) seedlings. The most notable change in the fatty acid composition was the increase of linolenic acid (18:3) with maturation of leaf cells, which occurred both in light- and dark-grown leaf tissues. In light-grown leaves, the increase of 18:3 with maturation was mainly attributed to the increase of monogalactosyldiacylglycerol (MGD) and also to the increase of the 18:3 level of MGD. In dark-grown leaves, the increase of 18:3 in the leaf apex was caused by the increase of the levels of MGD and digalactosyldiacylglycerol (DGD) and also by the increase of the 18:3 levels of within these two lipids. Since MGD and DGD are mainly found in plastid membranes, these findings indicate that both the synthesis of galactolipids and the formation of 18:3 these lipids take place during plastid development. The plastid ω-3 fatty acid desaturase is responsible for the formation of 18:3 in plastid membrane lipids. To investigate the regulation of desaturation, we isolated a gene for wheat plastid ω-3 fatty acid desaturase (TaFAD7). The mRNA level of TaFAD7 in light-grown leaves was much higher than that in dark-grown leaves. During the greening of etiolated leaves the level of TaFAD7 mRNA increased significantly, accompanied by an increase of the 18:3 level of total fatty acids. On the other hand, the levels of TaFAD7 mRNA were almost the same in all the leaf sections of both light- and dark-grown leaf tissues. These results suggest that the effect of the expression of the TaFAD7 gene on the increase of the 18:3 level is different between the leaf development under continuous light- or dark-conditions and the light-induced greening process of etiolated leaves. The increase of 18:3 content of MGD (or MGD and DGD) with maturation is apparently regulated not solely by the level of TaFAD7 mRNA. 相似文献
998.
Changes in fluxes of cytokinins in exudates transported viathe xylem from roots of rice plants cvs. Nipponbare (a standardJapanese cultivar) and Akenohoshi (a slowly senescing cultivar)were measured by mass spectrometry with deuterium-labeled standards.The fluxes of zeatin (Z), trans-ribosylzeatin (trans-RZ), N6-isopentenyladenine(iP), and "conjugated Z" (Z in the hydrolysates of highly polarfractions) decreased from heading to the late ripening stagein both cultivars. At the late ripening stage, iP and Z couldno longer be detected, while the flux of N6-isopentenyladenosine(iPA) increased slightly. In Akenohoshi, conjugated Z was thepredominant cytokinin from heading to the middle of the ripeningstage. The flux of each of the cytokinins in Akenohoshi washigher than that in Nipponbare at every time point, with theexception of the flux of iPA just after heading. The total concentrationof cytokinins in the xylem exudate of Akenohoshi was higherthan that of Nipponbare after the middle of ripening stage.The chlorophyll content of the third leaves, which were senescingrapidly, was significantly correlated with the flux of totalcytokinins per plant or per unit leaf area. These results suggestthat the larger amounts of cytokinins, in particular conjugatedZ, transported from the roots to the shoots caused the slowsenescence of leaves in Akenohoshi during the ripening stage. (Received May 9, 1994; Accepted July 1, 1995) 相似文献
999.
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
1000.
Tomohiro Ando Tetsuo Kato Kazuyuki Ishihara Hideki Ogiuchi Katsuji Okuda 《Microbiology and immunology》1995,39(5):321-327
The production of HSP by periodontopathic Gram-negative bacteria was examined by SDS-PAGE, two dimensional gel electrophoresis, and Western blotting using monoclonal antibodies against HSPs. Strains of Actinobacillus actinomycetemcomitans, Eikenella corrodens, Fusobacterium nucleatum, Prevotella intermedia, Prevotella nigrescens, Prevotella melaninogenica, and Treponema socranskii species produced HSP which reacted with anti-Yersinia enterocolitica HSP 60 and/or mycobacterial 65-kDa HSP monoclonal antibodies. It was found that gingival homogenate samples from patients with adult periodontitis reacted with anti-human HSP 60 and bovine brain HSP 70 monoclonal antibodies. Antibodies which reacted with bacterial HSP were also found in a serum sample from a periodontitis patient. The present study suggests that HSPs are implicated in the human periodontal disease process. 相似文献