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991.
Sachiko Nomura Taku Miyasho Naoyuki Maeda Katsumi Doh‐ura Hiroshi Yokota 《Proteomics》2009,9(16):4029-4035
It is desirable to make the diagnosis in live cattle with bovine spongiform encephalopathy (BSE), and thus surrogate markers for the disease have been eagerly sought. Serum proteins from BSE cattle were analyzed by 2‐D Western blotting and TOF‐MS. Autoantibodies against proteins in cytoskeletal fractions prepared from normal bovine brains were found in the sera of BSE cattle. The protein recognized was identified to be glial fibrillary acidic protein (GFAP), which is expressed mainly in astrocytes in the brain. The antigen protein, GFAP, was also found in the sera of BSE cattle. The percentages of both positive sera in the autoantibody and GFAP were 44.0% for the BSE cattle, 0% for the healthy cattle, and 5.0% for the clinically suspected BSE‐negative cattle. A significant relationship between the presence of GFAP and the expression of its autoantibody in the serum was recognized in the BSE cattle. These findings suggest a leakage of GFAP into the peripheral blood during neurodegeneration associated with BSE, accompanied by the autoantibody production, and might be useful in understanding the pathogenesis and in developing a serological diagnosis of BSE in live cattle. 相似文献
992.
The factors of bile tolerance (as one among the fundamental characteristics of probiotic bacteria) were determined in lactococci
by using plasmid variants. Bile tolerance of Lactococcus lactis wild-type (WT) strains 527 and N7 (determined by viability counts on bile-containing agar) was equivalent to the corresponding
plasmid-free derivatives. In contrast, L. lactis WT strain DRC1 had lower bile tolerance than its plasmid-free derivative DRC1021. Plasmid pDR1-1B, extracted from strain
DRC1, was introduced into strain DRC1021 by co-transformation with the vector plasmid pGKV21 as an indicator. Strain DRC121
(DRC1021 harboring pGKV21) had good bile tolerance as did strain DRC1021, while strain DRC13 (DRC1021 harboring both pDR1-1B
and pGKV21) did not. Fatty acid (FA) composition was different between strains DRC121 and DRC13. The plasmid pDR1-1B or plasmid
profile and FA composition are key factors for bile tolerance of strain DRC1, and therefore changing the plasmid profile might
be a way of modulating bile tolerance in lactococci. 相似文献
993.
994.
Rie Oka Katsuyuki Miura Masaru Sakurai Koshi Nakamura Kunimasa Yagi Susumu Miyamoto Tadashi Moriuchi Hiroshi Mabuchi Junji Koizumi Hideki Nomura Yoshiyu Takeda Akihiro Inazu Atsushi Nohara Masa‐Aki Kawashiri Shinya Nagasawa Junji Kobayashi Masakazu Yamagishi 《Obesity (Silver Spring, Md.)》2010,18(1):153-160
Regional fat distribution rather than overall fat volume has been considered to be important to understanding the link between obesity and metabolic disorders. We aimed to evaluate the independent associations of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) with metabolic risk factors in apparently healthy middle‐aged Japanese. Participants were 1,119 men and 854 women aged 38–60 years who were not taking medications for diabetes, hypertension, or dyslipidemia. VAT and SAT were measured by use of computed tomography (CT) scanning. VAT and SAT were significantly and positively correlated with each other in men (r = 0.531, P < 0.001) and women (r = 0.589, P < 0.001). In multiple regression analyses, either measure of abdominal adiposity (VAT or SAT) was positively associated with blood pressure, fasting plasma glucose, and log triglyceride (P < 0.001) and inversely with high‐density lipoprotein (HDL)‐cholesterol (P < 0.001). When VAT and SAT were simultaneously included in the model, the association of VAT with triglycerides was maintained (P < 0.001) but that of SAT was lost. The same was true for HDL‐cholesterol in women. For fasting plasma glucose, the association with VAT was strong (P < 0.001) and the borderline association with SAT was maintained (P = 0.060 in men and P = 0.020 in women). Both VAT and SAT were independently associated with blood pressure (P < 0.001). Further adjustment for anthropometric indices resulted in the independent association only with VAT for all risk factors. In conclusion, impacts of VAT and SAT differed among risk factors. VAT showed dominant impacts on triglyceride concentrations in both genders and on HDL‐cholesterol in women, while SAT also had an independent association with blood pressure. 相似文献
995.
The medicinal plant Psychotria ipecacuanha produces ipecac alkaloids, a series of monoterpenoid-isoquinoline alkaloids such as emetine and cephaeline, whose biosynthesis derives from condensation of dopamine and secologanin. Here, we identified three cDNAs, IpeOMT1–IpeOMT3, encoding ipecac alkaloid O-methyltransferases (OMTs) from P. ipecacuanha. They were coordinately transcribed with the recently identified ipecac alkaloid β-glucosidase Ipeglu1. Their amino acid sequences were closely related to each other and rather to the flavonoid OMTs than to the OMTs involved in benzylisoquinoline alkaloid biosynthesis. Characterization of the recombinant IpeOMT enzymes with integration of the enzymatic properties of the IpeGlu1 revealed that emetine biosynthesis branches off from N-deacetylisoipecoside through its 6-O-methylation by IpeOMT1, with a minor contribution by IpeOMT2, followed by deglucosylation by IpeGlu1. The 7-hydroxy group of the isoquinoline skeleton of the aglycon is methylated by IpeOMT3 prior to the formation of protoemetine that is condensed with a second dopamine molecule, followed by sequential O-methylations by IpeOMT2 and IpeOMT1 to form cephaeline and emetine, respectively. In addition to this central pathway of ipecac alkaloid biosynthesis, formation of all methyl derivatives of ipecac alkaloids in P. ipecacuanha could be explained by the enzymatic activities of IpeOMT1–IpeOMT3, indicating that they are sufficient for all O-methylation reactions of ipecac alkaloid biosynthesis. 相似文献
996.
997.
Koji Nagao Nao Inoue Masashi Inafuku Bungo Shirouchi Takanori Morooka Saori Nomura Naoki Nagamori Teruyoshi Yanagita 《The Journal of nutritional biochemistry》2010,21(5):418-423
Nonalcoholic fatty liver disease (NAFLD) is emerging as the most common liver disease in industrialized countries. Thus, the discovery of food components that would ameliorate NAFLD is of interest. Various mushrooms have been used in folk medicine for the treatment of lifestyle diseases in eastern countries and several compounds that modulate immune system, lower blood lipid levels, inhibit tumor and viral action have been isolated from them. In this study, we tested whether feeding Panellus serotinus (Mukitake) to db/db mice protects them from hepatic injury. After 4 weeks of feeding, hepatomegaly, hepatic triglyceride accumulation and elevated hepatic injury markers in serum were markedly alleviated in Mukitake-fed db/db mice compared with control mice. These effects were partly attributable to the enhancement of lipolytic enzyme activity and the suppression of lipogenic enzyme activities due to the Mukitake diet. The severe hyperinsulinemia in control db/db mice tended to attenuate in Mukitake-fed mice due to an enhanced production of adiponectin, which improves insulin sensitivity. Moreover, production of monocyte chemoattractant protein 1 (MCP1), an inflammatory cytokine, was markedly suppressed by the Mukitake diet. In addition, water-soluble extracts of Mukitake powder showed an inhibitory effect on inhibitor of κB (IκB) kinase (IKK) β, whose activation is required for nuclear factor κB (NFκB)-mediated inflammatory response. We speculate that the development and progression of NAFLD was prevented by the reduction of MCP1 production through the interference in the IKKβ–NFκB signaling pathway in Mukitake-fed db/db mice. 相似文献
998.
Shintaro Suzuki Kasthuraiah Maddali Chie Hashimoto Emiko Urano Nami Ohashi Tomohiro Tanaka Taro Ozaki Hiroshi Arai Hiroshi Tsutsumi Tetsuo Narumi Wataru Nomura Naoki Yamamoto Yves Pommier Jun A. Komano Hirokazu Tamamura 《Bioorganic & medicinal chemistry》2010,18(18):6771-6775
Structure–activity relationship studies were conducted on HIV integrase (IN) inhibitory peptides which were found by the screening of an overlapping peptide library derived from HIV-1 gene products. Since these peptides located in the second helix of Vpr are considered to have an α-helical conformation, Glu-Lys pairs were introduced into the i and i + 4 positions to increase the helicity of the lead compound possessing an octa-arginyl group. Ala-scan was also performed on the lead compound for the identification of the amino acid residues responsible for the inhibitory activity. The results indicated the importance of an α-helical structure for the expression of inhibitory activity, and presented a binding model of integrase and the lead compound. 相似文献
999.
1000.
Hideaki Matsuura Tadayoshi Hata Masafumi Miyata Yoshimi Yoshitani Yoko Sano Kenji Suzuki Toshio Yamazaki Hiroko Nomura Syunji Nagaoka 《Biological Sciences in Space》2003,17(3):261-262
We examined the developmental change by which autonomic neural activity associated respiration modulates spontaneous firing rate of sinus (SA) node and atrioventricular (AV) conduction in premature infants born with low birth weight (LBWI). The purpose of this study was to clarify whether variation of PR is correlated with that of PP or those are independent in LBWI with immature autonomic nervous system. We investigated, therefore, whether there are spontaneous functional differences in the innervation of SA and AV nodes. Further, we evaluated the maturation of autonomic nervous system progressing in the period, on the day of birth (Day 0) to approximately one month after the birth (Month 1). This study was performed in thirteen LBWI during deep sleep. EEG, EOG, ECG, respiratory waves were digitized on line, spontaneous firing cycle of SA node (PP), and AV nodal conduction time (PR) that were recorded on Day 0 and Month 1. Then, the data were analyzed as follows: 1) correlations among the means and standard deviations (SD) of PP, PR and RR, 2) variance evaluation of PP and PR intervals by Lorenz plot analysis method, 3) correlation analysis among PP, PR and RR intervals by linear regression method and 4) frequency analysis for PP and PR intervals by high-speed Fourier transform method (FFT) and determination of frequency density. The PP interval decreased as growing in the period. Contrary PR interval increased. In LBWI, the automatic nervous activities including parasympathetic nerve activity for spontaneous firing cycle of SA node and ventricular excitation cycle on Month 1 were higher than Day 0. It was assumed that the vagal nerve activity for the AV conduction was enhanced. However, there was no significant change in linear regression slope for the spontaneous firing cycle of SA node and the AV conduction time. Postnatal LF/HF changes for PP and PR obtained by frequency analysis, were opposite. Therefore, it was suggested that the maturity of autonomic nervous system progresses in the period, Day 0 to approximately Month 1, but the variations in PP and PR are independent each other. 相似文献