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71.
Role of nitric oxide in lipopolysaccharide-induced hepatic injury in D-galactosamine-sensitized mice as an experimental endotoxic shock model 总被引:4,自引:0,他引:4 下载免费PDF全文
Morikawa A Kato Y Sugiyama T Koide N Chakravortty D Yoshida T Yokochi T 《Infection and immunity》1999,67(3):1018-1024
The role of nitric oxide (NO) in lipopolysaccharide (LPS)-induced hepatic injury was studied in D-galactosamine (D-GalN)-sensitized mice. The inducible isoform of NO synthase (iNOS) was immunohistochemically detected on hepatocytes around blood vessels in livers of mice injected with D-GalN and LPS not on hepatocytes in mice injected with D-GalN or LPS alone, although mRNA for iNOS was found in those mice. Nitrotyrosine (NT) was also found in livers of mice injected with D-GalN and LPS. The localization of NT was consistent with that of iNOS, and the time courses of NT and iNOS expression were almost the same. Expression of iNOS and NT was detected exclusively in the hepatic lesions of mice injected with D-GalN and LPS. Anti-tumor necrosis factor alpha neutralizing antibody inhibited iNOS and NT expression and hepatic injury. The results suggested that NO from iNOS may play a role in LPS-induced hepatic injury on D-GalN-sensitized mice as an experimental endotoxic shock model. 相似文献
72.
Kiyohisa Sekizawa MDa Hideki Nakazawa MDa Masatoshi Morikawa MDa Kohei Yamauchi MDb Kazutaka Maeyama MDc Takehiko Watanabe MDc Hidetada Sasaki MDa 《The Journal of allergy and clinical immunology》1995,96(6)
Background: Histamine N-methyltransferase (HMT) modulates histamine- and antigen-induced bronchoconstriction. However, it is unclear whether vascular permeability evoked by an allergic reaction can be exaggerated by inhibition of HMT activity. Methods: We studied the effects of intravenously injected SKF 91488, a specific HMT inhibitor, on increases in plasma extravasation induced by intravenously injected histamine in unsensitized guinea pigs and by intravenously injected ovalbumin antigen in guinea pigs sensitized to ovalbumin in vivo with Evans blue dye as a marker. Results: Pretreatment with SKF 91488 shifted, in a dose-dependent fashion, the dose-response curves of the leakage of dye to histamine to lower concentrations in the trachea, main bronchi, and nasal mucosa. Likewise, pretreatment with SKF 91488 (20 mg/kg intravenously) significantly increased the leakage of dye induced by ovalbumin antigen (200 μg/kg intravenously) in three parts of the airway (p < 0.05). In contrast to SKF 91488, intravenously injected aminoguanidine, a specific inhibitor of diamine oxidase (16 mg/kg intravenously), did not alter the leakage of dye induced by histamine (from 0.001 μg/kg to 10 μg/kg intravenously) (p > 0.20). HMT activities were observed in the nasal mucosa, as well as in the trachea and main bronchi, as shown in a previous study. Conclusion: These findings suggest that HMT modulates the effects of exogenous histamine and endogenously released histamine induced by antigen challenge on plasma extravasation in the airway in guinea pigs in vivo. (J ALLERGY CLIN IMMUNOL 1995;96:910-6.) 相似文献
73.
Yamada H Shimada S Morikawa M Iwabuchi K Kishi R Onoé K Minakami H 《Molecular human reproduction》2005,11(6):451-457
The aim of this cohort study was to investigate immunophenotypic characteristics of natural killer (NK) cells by assessing specific molecules expressed in the decidua of sporadic miscarriages and induced abortions. The deciduae were obtained from 29 consecutively seen women whose pregnancies ended in first trimester miscarriages (MS), and the fetal chromosome karyotype of these MS was analysed. Additionally, 13 deciduae were obtained from induced abortion (IA) with informed consent. The expression of perforin, CD94, CD161, CD158a, CD158b, CD244 on CD3-CD56+NK cells, and perforin on CD3+CD8+ T cells was analysed by flow cytometry. The CD158a (mean+/-SD, 26.2+/-14.7%) and CD94 (50.2+/-25.7%) expressions in MS with normal chromosome karyotype (MSNK; n=11) were significantly decreased as compared with those (41.5+/-19.5%, 71.4+/-20.4%) in MS with abnormal karyotype (MSAK; n=18) and those (44.3+/-21.9%, 80.8+/-17.5%) in IA (n=13). Conversely, the perforin expression on CD3-CD8-CD56+NK cells (76.3+/-11.0%) and CD3+CD8+T cells (30.6+/-9.2%) in MSNK was significantly increased as compared with those (66.8+/-16.6%, 23.6+/-8.7%) in MSAK and those (62.9+/-11.6%, 19.7+/-8.1%) in IA. A positive correlation between CD94 and CD158a expressions on NK cells, negative correlations between CD94 on NK cells and perforin on NK cells/T cells, and between CD158a on NK cells and perforin on T cells were found in the decidua. A divergence of NK cell repertoire in the decidua might be related to aetiology of sporadic MSNK. 相似文献
74.
The evaluation of gastroesophageal reflux symptoms in patients with bronchial asthma 总被引:1,自引:0,他引:1
Lower esophageal sphincter pressure (LESP) and extended pH monitoring of the distal esophagus were assessed in 15 asthmatic children in order to evaluate the most important symptoms of suspected gastroesophageal reflux (GER)-asthma. As a result, episodes of asthmatic attacks after overeating were closely correlated with GER as determined by decreased LESP and high pH score. 相似文献
75.
The IBD6 Crohn's disease locus demonstrates complex interactions with CARD15 and IBD5 disease-associated variants 总被引:2,自引:0,他引:2
van Heel DA Dechairo BM Dawson G McGovern DP Negoro K Carey AH Cardon LR Mackay I Jewell DP Lench NJ 《Human molecular genetics》2003,12(20):2569-2575
Genetic studies in inflammatory bowel disease have identified multiple susceptibility loci, whose relevance depends critically on verification in independent cohorts. Genetic variants associated with Crohn's disease have now been identified on chromosomes 5 (IBD5/5q31 risk haplotype) and 16 (IBD1 locus, CARD15/NOD2 mutations). Stratification of genome-wide linkage analyses by disease associated variants is now possible, offering both increased power for identification of other loci and improved understanding of genetic mechanisms. We performed a genome-wide scan of 137 Crohn's disease affected relative pairs from 112 families. Multipoint non-parametric linkage analyses were performed, with further stratification of affection status by common CARD15 mutations and the IBD5 haplotype. We verified linkage of Crohn's disease to regions on chromosome 3 (P=0.0009) and X (P=0.001) in our cohort. Linkage to chromosome 16 (IBD1) was observed in Crohn's disease pairs not possessing common CARD15 mutations (P=0.0007), approximately 25 cM q telomeric of CARD15. Evidence for linkage to chromosome 19 (IBD6) was observed in Crohn's disease pairs not possessing CARD15 mutations (P=0.0001), and in pairs possessing one or two copies of the IBD5 risk haplotype (P=0.0005), with significant evidence for genetic heterogeneity and epistasis, respectively. These analyses demonstrate the complex genetic basis to Crohn's disease, and show that the discovery of disease-causing variants may be used to aid identification of further susceptibility loci in complex disease. 相似文献
76.
Nishimura H Tokuyama K Arakawa H Ohki Y Sato A Kato M Mochizuki H Morikawa A 《International archives of allergy and immunology》2002,129(4):320-326
BACKGROUND: Chronic exposure to fenoterol (FEN), a beta(2)-adrenergic receptor (beta(2)-AR) agonist, was shown to induce both airway hyperresponsiveness and airway remodeling in experimental animals. OBJECTIVE: We wanted to know the effects of chronic exposure to procaterol (PRO), a beta(2)-AR agonist, on airway function and structure, because this agent is widely used as a bronchodilator in Japan. For comparison, the effects of FEN were also examined. METHODS: Aerosolized PRO (0.1 or 1 mg/ml), FEN (1 mg/ml) or vehicle (0.9% NaCl) was given to guinea pigs 3 times a day for 6 weeks. Sublaryngeal deposition of these agents was calculated using radioisotopes. At 72 h after the last inhalation of PRO, FEN or vehicle, the dose-response relationship between lung resistance (R(L)) and intravenously administered acetylcholine (ACh) was measured. After measuring R(L), histological changes in noncartilaginous airway dimensions were evaluated. RESULTS: The amount of sublaryngeal deposition of 0.1 mg/ml PRO in the present study was speculated to be 100 times larger than that of therapeutic dose. ACh concentrations causing 2-fold, 10-fold and maximal increases in R(L) were not different in 4 groups tested. In the smaller membranous airways (<0.4 mm in diameter), but not the larger ones, thickening of adventitial areas was significantly greater in animals treated with beta(2)-AR agonists than in control animals (23 and 25, and 96% higher in animals treated with 0.1 and 1 mg/ml PRO or 1 mg/ml FEN, respectively). The degree of the increase was significantly less in PRO-treated animals than in FEN-treated animals (p < 0.01). CONCLUSION: Our results did not provide any evidence that regular inhalation of PRO at the therapeutic dose might induce bronchial hyperresponsiveness. In addition, huge amounts of PRO only caused a mild thickening of the adventitial areas, suggesting that PRO may be a weak inducer of airway remodeling compared with FEN. 相似文献
77.
Human muscle sympathetic neural and haemodynamic responses to tilt following spaceflight 总被引:6,自引:5,他引:6
Benjamin D. Levine James A. Pawelczyk rew C. Ertl James F. Cox Julie H. Zuckerman ré Diedrich Italo Biaggioni Chester A. Ray Michael L. Smith Satoshi Iwase Mitsuru Saito Yoshiki Sugiyama Tadaaki Mano Rong Zhang Kenichi Iwasaki Lynda D. Lane Jay C. Buckey Jr William H. Cooke Friedhelm J. Baisch David Robertson Dwain L. Eckberg C. Gunnar Blomqvist 《The Journal of physiology》2002,538(1):331-340
78.
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80.
Kenichi Ohashi Yo Kato Jun Kanno Tsutomu Kasuga 《Virchows Archiv : an international journal of pathology》1990,417(2):137-143
Summary Normal oesophagus specimens taken from 65 autopsy cases and surgical specimens from 127 oesophageal carcinoma cases were examined
histopathologically to determine melanocyte incidence and distribution. Melanocytes were found in the epithelio-stromal junction
in 7.7% of normal oesophagus specimens examined at autopsy, and in 29.9% of surgical cases with oesophageal carcinoma. Positive
specimens in the latter groups, especially from pre-operatively irradiated individuals, showed a more remarkable increase
of melanocytes than was evident in any of the normal oesophageal samples. There were no significant differences in incidence
between males and females, or between age groups. In cases where the cancer invaded into deeper stroma, the melanocytes were
mainly observed in the normal epithelium around the carcinomas. Epithelial and stromal elements of the melanotic mucosa commonly
showed hyperplastic changes such as acanthosis or basal cell hyperplasia, and chronic oesophagitis. Melanocytes were observed
most commonly in the lower part of the oesophagus, the site where malignant melanoma of the oesophagus, most often originates.
These results strongly suggest that the melanocyte increase observed in areas of hyperplastic epithelium and chronic oesophagitis
may play an important role as a precursor lesion for malignant melanoma in the oesophagus. 相似文献