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61.
Murata K Inami M Hasegawa A Kubo S Kimura M Yamashita M Hosokawa H Nagao T Suzuki K Hashimoto K Shinkai H Koseki H Taniguchi M Ziegler SF Nakayama T 《International immunology》2003,15(8):987-992
CD69, known as an early activation marker antigen on T and B cells, is also expressed on platelets and activated neutrophils, suggesting certain roles in inflammatory diseases. In order to address the role of CD69 in the pathogenesis of arthritis, we established CD69-null mice. CD69-null mice displayed a markedly attenuated arthritic inflammatory response when injected with anti-type II collagen antibodies. Cell transfer experiments with neutrophils, but not T cells or spleen cells, from wild-type mice into CD69-null mice restored the induction of arthritis. These results indicate a critical role for CD69 in neutrophil function in arthritis induction during the effector phase. Thus, CD69 would be a possible therapeutic target for arthritis in human patients. 相似文献
62.
Effect of ethanol treatment on metabolic activation and detoxification of esophagus carcinogenic N-nitrosamines in rat liver 总被引:3,自引:0,他引:3
In order to elucidate the mechanism underlying enhancement by ethanol of N-nitrosodiethylamine (DEN)- and N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumorigenesis in rats, hepatic levels of cytochrome P-450 (CYP) enzymes, mutagenic activation of several N-nitrosamines and three kinds of UDP-glucuronyltransferase (UDPGT) activities were assayed in F344 rats. Immunoblot analyses of microsomal CYP proteins revealed induction of CYP2E1 (approximately 2-fold), but not CYP2B1/2, 1A1/2 or 3A2, by treatment with 10% ethanol in the drinking water for 2 weeks. In contrast, s.c. treatment with 0.5 mg/kg NMBA three times per week for 2 weeks produced no significant alterations in the levels of these CYP species. Ethanol treatment also elevated the mutagenic activities of N-nitrosodimethylamine (DMN), DEN and N-nitrosopyrrolidine (NPYR) in strain TA100 up to 2.1-, 1.6- and 2.3-fold above each control, respectively. However, this was not the cases for four N-nitrosamines, including NMBA, in strain TA100 and two heterocyclic amines and aflatoxin B(1) in strain TA98. In addition, ethanol did not affect UDPGT activities towards 4-nitrophenol, bilirubin and testosterone. Hepatic CYP species responsible for mutagenic activation of selected N-nitrosodialkylamines were confirmed by use of specific CYP inducers and inhibitors with the liver from F344 and Wistar rats, indicating that DMN, DEN and NMBA are selectively activated by CYP2E1, predominantly by CYP2E1 with a slight contribution by CYP2B2 and selectively by CYP2B1/2, respectively. These results demonstrate that ethanol exerts an enhancing effect on mutagenic activation by CYP2E1 of DMN, DEN and NPYR, but does not affect that of NMBA and the other carcinogens by CYP2B1/2, 1A1/2 and 3A2 and UDPGT1A1, 1A6 and 2B1 activities. Consequently, this suggests that enhancement by ethanol of DEN-induced esophageal carcinogenesis in F344 rats can be attributed to an increase in hepatic activation during the initiation phase, but that of NMBA-induced tumorigenesis is not attributable to metabolic activation and inactivation via glucuronidation in liver. 相似文献
63.
Hirata T Iida A Shiraki-Iida T Kitazato K Kato A Nagai Y Hasegawa M 《Journal of virological methods》2002,104(2):125-133
An improved system is described to recover non-transmissible Sendai virus that lack the envelope fusion (F) gene from cloned cDNA. The system (1) used plasmids that expressed the F and the HN viral envelope proteins, as well as the plasmids that expressed the viral NP, P, and L proteins as helper plasmids for recovery, and (2) overlaid packaging cells that expressed the F protein. With this improved system, we have succeeded in recovery of F-defective Sendai virus expressing two foreign proteins, and expression vectors that do not contain the EGFP reporter gene. This system may provide the basis for constructing recombinant F-defective Sendai virus for preventing and treating human diseases in the form of vaccines and vectors for gene therapy. 相似文献
64.
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
65.
66.
Eva Müller Wolfgang Neuhofer Akihiro Ohno Silvia Rucker Klaus Thurau Franz-X. Beck 《Pflügers Archiv : European journal of physiology》1996,431(4):608-617
The distribution of heat shock proteins (HSP) HSP60, HSP73, HSP72 and HSP25 in the isoosmotic cortex and the hyperosmotic medulla of the rat kidney was investigated using Western blot analysis and immunohistochemistry. HSP73 was homogeneously distributed throughout the whole kidney. The level of HSP60 was high in the renal cortex and low in the medulla. HSP25 and HSP72 were present in large amounts in the medulla. Only low levels of HSP25 and almost undetectable amounts of HSP72 were found in the cortex. HSP25 exists in one nonphosphorylated and several phosphorylated isoforms. Western blot analysis preceded by isoelectric focussing showed that HSP25 predominates in its nonphosphorylated form in the outer medulla but in its phosphorylated form in cortex and inner medulla. Although this intrarenal distribution pattern was not changed during prolonged anaesthesia (thiobutabarbital sodium), a shift from the nonphosphorylated to the phosphorylated isoforms of HSP25 occurred in the medulla. The characteristic intrarenal distribution of the constitutively expressed HSPs (HSP73, HSP60, HSP25) may reflect different states of metabolic activity in the isoosmotic (cortex) and hyperosmotic (medulla) zones of the kidney. The high content of inducible HSP72 in the medulla most likely is a consequence of the osmotic stress imposed upon the cells by the high urea and salt concentrations in the hyperosmotic medullary environment. 相似文献
67.
Sun X Rokuhara A Tanaka E Gad A Mutou H Matsumoto A Yoshizawa K Kiyosawa K 《Journal of medical virology》2005,76(2):170-175
One hundred and forty four patients with chronic hepatitis B were tested to identify new mutations associated with hepatitis B e antigen (HBeAg) negativity, using a full genome sequence analysis. All the patients were Chinese and had hepatitis B virus infection of genotype C. Patients with none of the pre-core or core promoter mutations were significantly (P < 0.001) less common in the group with anti-HBe (13%) than in the group with HBeAg (56%). The complete nucleotide sequence was determined in four anti-HBe-positive patients who had neither pre-core nor core promoter mutations and in five HBeAg-positive patients who also had neither of these mutations (the groups were matched for age and sex). Six mutations were found to be significantly more common in the former group than in the latter: G529A (3/4 vs. 0/5), C934A (4/4 vs. 1/5), A1053G (4/4 vs. 1/5), G1915T/A (4/4 vs. 0/5), T2005C/A (4/4 vs. 0/5), and C3026T (3/4 vs. 0/5). Three of the six mutations were significantly more common in the four anti-HBe-positive patients who had neither pre-core nor core promoter mutations, compared to 11 HBeAg-positive patients who had pre-core and core promoter mutations, and also compared to 15 anti-HBe-positive patients who had pre-core and core promoter mutations, suggesting further the specificity of these mutations. Of the six mutations, two resulted in amino acid substitution in the polymerase protein, and one is located near the enhancer I region. The results suggest that the six newly discovered mutations are associated with HBeAg negativity. 相似文献
68.
Yamazaki K McGovern D Ragoussis J Paolucci M Butler H Jewell D Cardon L Takazoe M Tanaka T Ichimori T Saito S Sekine A Iida A Takahashi A Tsunoda T Lathrop M Nakamura Y 《Human molecular genetics》2005,14(22):3499-3506
The inflammatory bowel diseases (IBDs), Crohn's disease (CD) and ulcerative colitis, are chronic inflammatory disorders of the digestive tract. The pathogenesis of IBD is complicated, and it is widely accepted that immunologic, environmental and genetic components contribute to its etiology. To identify genetic susceptibility factors in CD, we performed a genome-wide association study in Japanese patients and controls using nearly 80,000 gene-based single nucleotide polymorphism (SNP) markers and investigated the haplotype structure of the candidate locus in Japanese and European patients. We identified highly significant associations (P = 1.71 x 10(-14) with odds ratio of 2.17) of SNPs and haplotypes within the TNFSF15 (the gene encoding tumor necrosis factor superfamily, member 15) genes in Japanese CD patients. The association was confirmed in the study of two European IBD cohorts. Interestingly, a core TNFSF15 haplotype showing association with increased risk to the disease was common in the two ethnic groups. Our results suggest that the genetic variations in the TNFSF15 gene contribute to the susceptibility to IBD in the Japanese and European populations. 相似文献
69.
70.
STUDY OBJECTIVES: The positional dependency of obstructive sleep apnea (OSA) is well known, but objective evidence for the positional effect on snoring is lacking. The aim of this study is to elucidate the effect of body position on snoring, and that of sleep stage as well. DESIGN: Retrospective analysis of the effects of body position and sleep stage on snoring in nonapneic snorers (snorer group) and OSA patients (apneic group). SETTING: A sleep laboratory in a national hospital in Japan. PATIENTS: Seventy-two patients who complained of habitual snoring and underwent overnight polysomnography. INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: In the lateral position, most subjects in the snorer group showed decreased snoring both in time (p = 0.0004) and intensity (p = 0.0003), but subjects in the apneic group showed variable changes. In the apneic group, the positional dependency of snoring (the ratio of lateral value to supine value) was correlated with supine apnea-hypopnea index (AHI), that is, OSA patients with higher supine AHI tended to show increased snoring in the lateral position. AS to the effect of sleep stage, snoring was increased in deeper non-rapid eye movement sleep and decreased in rapid eye movement sleep in a given position. CONCLUSIONS: This study demonstrated that the positional dependency is different between nonapneic snorers and OSA patients. Most of the nonapneic snorers snore less in the lateral position than in the supine position in contrast to OSA patients who often fail to decrease snoring even in the lateral position. 相似文献