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101.
Pulmonary fibrosis is an end-stage disorder for which efficacious therapeutic options are not readily available. Although its pathogenesis is poorly understood, pulmonary fibrosis occurs as a result of various inflammations. NKT cells modulate inflammation because of their ability to produce large amounts of cytokines by stimulation with their glycolipid ligand. In the present study, we investigated the effects of alpha-galactosylceramide (alpha-GalCer), a selective NKT cell ligand, on the development of bleomycin-induced pulmonary fibrosis. Treatment of mice with alpha-GalCer prolonged their survival under bleomycin administration by attenuating the development of pulmonary fibrosis. The protective effects of alpha-GalCer were associated with an increase in the pulmonary level of IFN-gamma and a decrease in the pulmonary level of fibrogenic cytokines such as TGF-beta and connective tissue growth factor. The initial pulmonary inflammation caused by bleomycin was also attenuated by alpha-GalCer with the reduction of the macrophage inflammatory protein-2 level. The protective effects of alpha-GalCer were markedly reduced in mice lacking NKT cells or as a result of treatment with anti-IFN-gamma Ab. These results suggest that alpha-GalCer suppresses bleomycin-induced acute pulmonary inflammation and thus attenuates the development of pulmonary fibrosis possibly by regulating several cytokine levels.  相似文献   
102.
Rosmarinic acid (RA) is contained in various Lamiaceae herbs used commonly as culinary herbs. Although RA has various potent physiological actions, little is known on its bioavailability. We therefore investigated the absorption and metabolism of orally administered RA in rats. After being deprived of food for 12 h, RA (50 mg/kg body weight) or deionized water was administered orally to rats. Blood samples were collected from a cannula inserted in the femoral artery before and at designated time intervals after administration of RA. Urine excreted within 0 to 8 h and 8 to 18 h post-administration was also collected. RA and its related metabolites in plasma and urine were measured by LC-MS after treatment with sulfatase and/or beta-glucuronidase. RA, mono-methylated RA (methyl-RA) and m-coumaric acid (COA) were detected in plasma, with peak concentrations being reached at 0.5, 1 and 8 h after RA administration, respectively. RA, methyl-RA, caffeic acid (CAA), ferulic acid (FA) and COA were detected in urine after RA administration. These components in plasma and urine were present predominantly as conjugated forms such as glucuronide or sulfate. The percentage of the original oral dose of RA excreted in the urine within 18 h of administration as free and conjugated forms was 0.44 +/- 0.21% for RA, 1.60 +/- 0.74% for methyl-RA, 1.06 +/- 0.35% for CAA, 1.70 +/- 0.45% for FA and 0.67 +/- 0.29% for COA. Approximately 83% of the total amount of these metabolites was excreted in the period 8 to 18 h after RA administration. These results suggest that RA was absorbed and metabolized as conjugated and/or methylated forms, and that the majority of RA absorbed was degraded into conjugated and/or methylated forms of CAA, FA and COA before being excreted gradually in the urine.  相似文献   
103.
Heme oxygenase-1 (HO-1) acts in cytoprotection against oxidants and aromatic hydrocarbons in cigarette smoke. A (GT)n dinucleotide repeat in the 5-flanking region of the human HO-1 gene (alias HMOX1) reduces HO-1 inducibility and shows length polymorphism, which is grouped into three classes: class S (<27 GT), class M (27–32 GT), and class L (33 GT) alleles. To investigate the correlation between the HO-1 gene polymorphism and the development of lung adenocarcinoma, we screened 151 Japanese patients with lung adenocarcinoma and 153 control subjects. Patients and control subjects were frequency-matched by age, gender, smoking history and proportion of chronic pulmonary emphysema. The proportion of class L allele frequencies, as well as that of genotypic frequencies in L allele carriers (LL, LM, and LS), were significantly higher in patients with lung adenocarcinoma than those of control subjects. The adjusted odds ratio (OR) for lung adenocarcinoma with class L allele vs non-L allele (M+S) was 1.6 [95% confidence interval (CI) 1.0–2.5, P=0.03] and that with L allele carriers vs. non-L allele carriers was 1.8 (95% CI 1.1–3.0, P=0.02). Furthermore, the risk of lung adenocaricinoma for L allele carriers versus non-L allele carriers was much increased in the group of male smokers (OR=3.3, 95% CI 1.5–7.4, P=0.004). However, in the female non-smokers, the proportion of L allele carriers did not differ between patients and control subjects (OR=0.93, 95% CI 0.4–2.0, P=0.85). These findings suggest that the large size of a (GT)n repeat in the HO-1 gene promoter may be associated with the development of lung adenocarcinoma in Japanese male smokers.  相似文献   
104.
Summary Glucosyltransferase fromAureobasidium, which produces panose and isomaltose from maltose, was immobilized by alginate gel or DEAE-cellulose at high efficiency (71 and 41% respectively). Alkylamine porous silica was less efficient as a support. The enzymatic profiles of immobilized enzymes were almost identical to the native one except that their stabilities to extreme pH, metal ions and inhibitors were improved. Both immobilization procedures successfully produced high amounts of panose, 125 mg ml–1 (alginate gel) or 141 mg ml–1 (DEAE-cellulose), from 300 mg ml–1 of maltose.  相似文献   
105.
Summary -Fructofuranosidase was immobilized by alginate gel at high efficiency (92 %). The extreme long-term continuous reaction (half-life, 275 days) was achieved by the immobilized enzyme using sucrose at high concentration (500 mg ml–1) to produce fructo-olicosaccharides, such as 1-kestose (Fru21Fru21aGlc) and nystose (Fru21Fru21Fru21aGlc).  相似文献   
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The chemical structure of the oligosaccharide produced from sucrose by an enzyme extracted fromAureobasidium sp. ATCC 20524 was observed. The GC-MS analysis by methylation indicated that this oligosaccharide is composed of 2-linked, 1,2-linked fructose and 1-linked glucose. The [13C]-NMR spectrum indicated that the 1,2-linked glycosidic linkages of fructose of this oligosaccharide are, and the 1-linked glycosidic linkages of fructose are . This investigation suggested that this oligosaccharide is isokestose.  相似文献   
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