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41.
Takashi Umeda Kazuo Saito Masashi Matsuzaka Shigeyuki Nakaji Manabu Totsuka Toshiki Okumura Toshiaki Tsukamoto Makoto Yaegaki Umi Kudoh Ippei Takahashi 《Luminescence》2008,23(3):115-120
In order to examine in detail the influence on the neutrophil immune function in sumo wrestlers of performing traditional and original training we examined changes in the neutrophil immune function in 17 male amateur university sumo wrestlers (aged 20.2 ± 1.5 years), before (‘Pre’) and after the training (‘Post’) for 2.5 h under fasting conditions. Assays included blood leukocyte and neutrophil counts, serum concentration of immunoglobulins, complements, myogenic enzymes and neutrophil oxidative burst activity (OBA) and phagocytic activity (PA). Myogenic enzymes, neutrophil counts, the ratio of neutrophil counts:leukocyte counts significantly increased and immunoglobulins and complements decreased in Post compared with Pre. There was a positive correlation between the change of neutrophil counts before and after the training and the change of creatine kinase (r = 0.667, p < 0.01). The Post OBA significantly increased and PA significantly decreased compared with Pre. It was concluded that sumo training causes muscular damage and an increase in the neutrophil count as a response. In this time, although OBA increased, PA decreased after training. Compensation between PA and reactive oxygen species production may exist to maintain the overall integrity of the neutrophil immune function. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
42.
Jeong BY Jeong WG Moon SK Ohshima T 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2002,131(2):251-259
The effect of dietary lipid on the fatty acid composition of muscle, testis and ovary of cultured sweet smelt, Plecoglossus altivelis, was investigated and compared with that of wild sweet smelt. Cultured fish were fed three different diets for 12 weeks: a control diet rich in docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) (CO group); a diet deficient in DHA and EPA (DP group); and a diet rich in alpha-linolenic acid (ALA, 18:3n-3), but deficient in DHA and EPA (LP group). The fatty acid composition of muscle and gonad lipids was related with dietary fatty acids. Despite the difference in DHA and EPA content in the diets, muscles and gonads, respectively, contained almost equal levels of DHA and EPA in each CO and DP group. However, the muscle and gonad of the LP group showed a lower level of DHA than other groups, due to having the highest level of ALA. In the wild fish muscle, the DHA content was similar to that of CO and DP groups, but the EPA content showed the highest level in all groups. There was no difference in the muscle fatty acid proportions between male and female. On the other hand, the testes of cultured and wild fish were rich in DHA, EPA, docosapentaenoic acid and arachidonic acid, while ovaries were rich in oleic, palmitoleic, linoleic acids and ALA. Moreover, of all the groups, the fish fatty acid composition of the LP group was closest to that of wild fish. These results indicate that in the sweet smelt, tissue n-3 polyunsaturated fatty acids (PUFAs) greater than C20 can be synthesized from dietary precursors and special fatty acids are preferentially accumulated to the testis or ovary, respectively, to play different physiological functions. 相似文献
43.
Bacterial cometabolic degradation of chlorinated paraffins 总被引:1,自引:0,他引:1
Toshio Omori Toshiaki Kimura Tohru Kodama 《Applied microbiology and biotechnology》1987,25(6):553-557
Summary Cometabolic dechlorination of chlorinated paraffins was demonstrated in the presence of n-hexadecane by bacterial strains (HK-3, HK-6, HK-8, and HK-10) isolated from soil samples.Eleven per cent of chlorine of chlorinated paraffin-150 (CP-150) was released by strain HK-3. The mixed culture of strain HK-3, catalyzing the dechlorination of terminal chlorine of chloroalkane, and strain H15-4, capable of releasing the chlorine from 2-chlorinated fatty acids, dechlorinated CP-150 up to 13%. The mixed culture of the four strains (HK-3, HK-6, HK-8, and HK-10) performed the dechlorination of CP-150 by cometabolism in a jar fermentor pH at 7.0. The amount of chloride released from the chlorinated paraffins tested was in the range of 15–57%.The activated sludge acclimatized to n-hexadecane for 60 days showed a little dechlorination activity to CP-150. 相似文献
44.
Odaka C Mizuochi T Yang J Ding A 《Journal of immunology (Baltimore, Md. : 1950)》2003,171(3):1507-1514
Macrophage-derived secretory leukocyte protease inhibitor (SLPI) can be induced locally as well as systemically in response to microbial products such as LPS and lipotechoic acid. It is not known whether phagocytosis of apoptotic cells, an essential function of macrophages, can regulate expression and secretion of SLPI. In this study, we report that exposure of peritoneal macrophages of BALB/c mice or murine macrophage cell lines RAW264.7 and J774.1 to apoptotic target cells induced an elevation in SLPI secretion. Secreted SLPI retained its antichymotrypsin activity. SLPI expression in thymuses from BALB/c mice that had been injected with anti-CD3 Ab to induce apoptosis of thymocytes was also elevated both at the mRNA and protein levels. Colchicine, a microtubular inhibitor, blocked the internalization of apoptotic cells by macrophages but not SLPI secretion, suggesting that surface recognition of apoptotic cells is sufficient for the induction of SLPI. Exposure of RAW264.7 cells to apoptotic CTLL-2 cells induced both SLPI and TNF-alpha, and addition of IFN-gamma inhibited SLPI but augmented TNF-alpha production. Transfection of either the secreted or a nonsecreted form of SLPI into RAW264.7 cells led to suppression of TNF-alpha production in response to apoptotic cells. Thus, macrophages secrete an increased amount of SLPI when encountering apoptotic cells, which may help to attenuate potential inflammation during clearance of these cells. 相似文献
45.
Wu X Kobori H Orita I Zhang C Imanaka T Xing XH Fukui T 《Biotechnology and bioengineering》2012,109(1):53-62
A novel thermostable NAD(P)H oxidase from the hyperthermophilic archaeon Thermococcus kodakarensis KOD1 (TkNOX) catalyzes oxidation of NADH and NADPH with oxygen from atmospheric air as an electron acceptor. Although the optimal temperature of TkNOX is >90°C, it also shows activity at 30°C. This enzyme was used for the regeneration of both NADP(+) and NAD(+) in alcohol dehydrogenase (ADH)-catalyzed enantioselective oxidation of racemic 1-phenylethanol. NADP(+) regeneration at 30°C was performed by TkNOX coupled with (R)-specific ADH from Lactobacillus kefir, resulting in successful acquisition of optically pure (S)-1-phenylethanol. The use of TkNOX with moderately thermostable (S)-specific ADH from Rhodococcus erythropolis enabled us to operate the enantioselective bioconversion accompanying NAD(+) regeneration at high temperatures. Optically pure (R)-1-phenylethanol was successfully obtained by this system after a shorter reaction time at 45-60°C than that at 30°C, demonstrating an advantage of the combination of thermostable enzymes. The ability of TkNOX to oxidize both NADH and NADPH with remarkable thermostability renders this enzyme a versatile tool for regeneration of the oxidized nicotinamide cofactors without the need for extra substrates other than dissolved oxygen from air. 相似文献
46.
Ken Yamazaki Toshio Maruyama Toshiaki Ihara Ikuo Yasumasu 《Development, growth & differentiation》1997,39(1):105-109
The allelic division of the Na+ /K+ -ATPase α-subunit gene was found in eggs of the sea urchin Hemicentrotus pulcherrimus by polymerase chain reaction (PCR). Two PCR products of different lengths were detected from a genome in one embryo derived from a fertilized egg, although only one product in one embryo derived from an artificially activated egg by parthenogenesis was detected, indicating one copy of the gene in a haploid genome. One of the two PCR products from each fertilized egg was identical in size to the product from an artificially activated egg in the same batch. The other PCR product was the same in length as one of the products from the sperm with which the eggs were fertilized. These results indicate that recombination of the heteromeric alleles of the Na+ /K+ -ATPase α-subunit gene occurs in the sea urchin egg due to meiosis and fertilization. The sequencing of these products demonstrated that their exon sequences were identical and that the intron, inserted in the PCR products, generated polymorphism in length due to the frequency of the repeating 53 bp sequence and insertion/deletion of other two segments. 相似文献
47.
48.
Kinetic resolution of organosilicon compounds by stereoselective dehydrogenation with horse liver alcohol dehydrogenase 总被引:3,自引:0,他引:3
Toshiaki Fukui Min-Hua Zong Takuo Kawamoto Atsuo Tanaka 《Applied microbiology and biotechnology》1992,38(2):209-213
Streoselective dehydrogenation of three isomers of trimethylsilypropanol was carried out with horse liver alcohol dehydrogenase (HLADH, EC 1.1.1.1.) and optically active organosilicon compounds were obtained in a water-organic solvent two-layer system with coenzyme regeneration. Furthermore, we examined the effects of the silicon atom on stereoselectivity of HLADH compared to the corresponding carbon compounds. Substitution of the silicon atom for the carbon atom was found to improve the stereoselectivity of HLADH. For example, the optical purity of the remaining 1-trimethylsilyl-2-propanol was higher than 99% enantiomeric excess (ee) at 50% conversion, whereas that of the carbon analogue was 84% ee. This phenomenon was probably ascribable to the bulkiness of the organosilicon compounds derived from their longer Si-C bond. Kinetic analysis in an aqueous monolayer system demonstrated that the specific properties of the silicon atom greatly affected the reactivity of these substrate compounds.Correspondence to: A. Tanaka 相似文献
49.
50.
Daisuke Sato Takahiro Tsuchikawa Tomoko Mitsuhashi Yutaka Hatanaka Katsuji Marukawa Asami Morooka Toru Nakamura Toshiaki Shichinohe Yoshihiro Matsuno Satoshi Hirano 《PloS one》2016,11(3)
It has been clear that cancer-associated fibroblasts (CAFs) in the tumor microenvironment play an important role in pancreatic ductal adenocarcinoma (PDAC) progression. However, how CAFs relate to the patients’ prognosis and the effects of chemoradiation therapy (CRT) has not been fully investigated. Tissue microarrays (TMAs) representing 167 resected PDACs without preoperative treatment were used for immunohistochemical studies (IHC) of palladin, α-smooth muscle actin (SMA), and podoplanin. Correlations between the expression levels of these markers and clinicopathological findings were analyzed statistically. Whole sections of surgical specimens from PDACs with and without preoperative CRT, designated as the chemotherapy-first group (CF, n = 19) and the surgery-first group (SF, n = 21), respectively, were also analyzed by IHC. In TMAs, the disease-specific survival rate (DSS) at 5 years for all 167 cases was 23.1%. Seventy cases (41.9%) were positive for palladin and had significantly lower DSS (p = 0.0430). α-SMA and podoplanin were positive in 167 cases (100%) and 131 cases (78.4%), respectively, and they were not significantly associated with DSS. On multivariable analysis, palladin expression was an independent poor prognostic factor (p = 0.0243, risk ratio 1.60). In the whole section study, palladin positivity was significantly lower (p = 0.0037) in the CF group (5/19) with a significantly better DSS (p = 0.0144) than in the SF group (16/22), suggesting that stromal palladin expression is a surrogate indicator of the treatment effect after chemoradiation therapy. 相似文献