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101.
Increased peripheral blood Ia positive T cells and their effect on autologous mixed lymphocyte reaction in chronic active liver disease. 下载免费PDF全文
K Fukui S Kakumu H Murakami J Kuriki K Yoshioka N Sakamoto 《Clinical and experimental immunology》1984,58(1):90-96
We measured Ia antigen bearing peripheral blood T cells, as an index of immunological stimulation, of patients with chronic active liver diseases (CALD) by the rosette assay method. We also examined the role of Ia antigen which represents the products of the genes of the major histocompatibility complex on the autologous mixed lymphocyte reaction (AMLR) since this reaction may reflect self regulation of immune responses. The percentages of Ia positive T cells of 29 patients with CALD (17.1 +/- 4.3%, P less than 0.001) and of 12 patients with other liver diseases (12.9 +/- 2.4%, P less than 0.05) were increased when compared with that of normal individuals (10.7 +/- 2.0%). However, levels of Ia positive T cells activated by phytohaemagglutinin-P in patients with CALD and other liver diseases did not differ from normal subjects. Ia positive cells in OKT8 positive cells were markedly elevated (P less than 0.001), whereas those in OKT4 positive cells were decreased (P less than 0.01) in CALD. The impaired values for the AMLR correlated inversely (P less than 0.01) with the increased percentages of Ia positive T cells in patients with CALD. Further analysis showed that there was no suppression of the proliferation of Ia and OKT4 positive cells by Ia and OKT8 positive cells although the culture of increasing numbers of Ia and OKT8 positive cells and decreasing numbers of Ia and OKT4 positive cells gave a lesser AMLR value. These data suggest that the increase in Ia positive T cells and the alteration of Ia positive cells in the T cell subsets reflect an activation of immune system and provide further evidence in favour of an abnormality of the immunoregulatory system in CALD. 相似文献
102.
Endo S Inoue Y Fujino Y Yamada Y Sato N Wakabayashi G Sakamoto T Ishikura H Tanaka T Inada K Sato S 《Research communications in molecular pathology and pharmacology》2000,108(3-4):179-186
The FasL-Fas system is an apoptosis induction system and plays an important role in homeostasis and biophylaxis. The present study was conducted to investigate soluble Fas (sFas), soluble Fas ligand (sFasL), and tumor necrosis factor alpha (TNF-alpha) in patients with acute pancreatitis. As acute pancreatitis became severe, the levels of sFas in the serum increased significantly, while those of sFasL decreased significantly. A significant inverse correlation was observed between the serum levels of sFas and those of sFasL. Also, a significant positive correlation was observed between the levels of TNF-alpha and sFas. A greater increase in serum sFas and decrease in serum sFasL levels was observed in patients with complicating multiple organ dysfunction syndrome (MODS) than in those without it. The results of the study suggest that the pathological aggravation of acute pancreatitis could be related to changes in the Fas-FasL system. 相似文献
103.
Toshikatsu Shimizu Koji Yoshitomi Junichi Taniguchi Masashi Imai 《Pflügers Archiv : European journal of physiology》1989,414(5):500-508
Morphological studies have demonstrated that a chronic increase in distal Na+ delivery causes hypertrophy of the distal convoluted tubule (DCT). To examine whether high NaCl-intake also causes functional changes in the well defined DCT, we measured transmural voltage (V
T), lumen-to-bath Na+ flux (J
Na(LB)), and net K+ secretion (J
K(net)) in DCTs obtained from control rabbits and those on high NaCl-intake diets. The lumen negativeV
T was significantly greater in the high NaCl group than in the control group. The net K+ secretion (pmol mm–1 min–1) was greater in the high NaCl-intake group (54.1±13.0 vs 14.7±5.6). The K+ permeabïlities in both luminal and basolateral DCT membranes, as assessed by the K+-induced transepithelial voltage deflection inhibitable with Ba2+, were increased in the experimental group. The lumen-to-bath22Na flux (pmol mm–1 min–1) was also greater in the experimental group (726±119 vs 396±65). TheV
T component inhibitable with amiloride was also elevated in the high NaCl-intake group. Furthermore, Na+–K+-ATPase activity of the DCT was higher in the experimental than in the control group. We conclude that high NaCl intake increases both Na+ reabsorption and K+ secretion by the DCT. This phenomenon is associated with an increased Na+–K+-ATPase activity along with increased Na+ and K+ permeabilities of the luminal membrane, and an increase in the K+ permeability of the basolateral membrane. Cellular mechanisms underlying these functional changes remain to be established. 相似文献
104.
Effects of sodium, potassium and calcium ions on the slow wave in the circular muscle of the guinea-pig stomach 总被引:1,自引:0,他引:1
1. The contribution of Na, K and Ca ions to the generation of slow waves in the circular muscle of the guinea-pig stomach was studied. 相似文献
105.
Frequent importation of enterovirus 71 from surrounding countries into the local community of Yamagata, Japan, between 1998 and 2003 下载免费PDF全文
Mizuta K Abiko C Murata T Matsuzaki Y Itagaki T Sanjoh K Sakamoto M Hongo S Murayama S Hayasaka K 《Journal of clinical microbiology》2005,43(12):6171-6175
Phylogenetic analysis of 45 enterovirus 71 (EV71) isolates for 6 years in Yamagata, Japan, clarified that the annual outbreak of hand-foot-and-mouth disease was due to four genetically distinct subgenogroups, including a novel "B5." Our results suggest that the importation of EV71 from surrounding countries has had a major epidemiological impact on the local community used in our study. 相似文献
106.
Kashimura T Kodama M Hotta Y Hosoya J Yoshida K Ozawa T Watanabe R Okura Y Kato K Hanawa H Kuwano R Aizawa Y 《Virchows Archiv : an international journal of pathology》2004,444(3):283-292
Coxsackievirus B is the most common cause of viral myocarditis and is particularly virulent in neonates and children. Adenovirus is also a leading cause of the disease. The determinant of tropism for both viruses is considered to be the expression of coxsackievirus and adenovirus receptor (CAR) in target organs. However, developmental change and physiological localization of CAR in the heart are unknown. We examined expression levels of CAR in rat hearts by quantitative real-time polymerase chain reaction and Western blot analysis and found that CAR decreased gradually during postnatal development, although CAR was detectable, even in adults. Immunohistochemistry revealed CAR on the whole surface of cardiomyocytes in immature rat hearts. In contrast, CAR was detected predominantly on intercalated disks in the adult heart and was accumulated especially at the contact point between the cultured cardiomyocytes, even though they were prepared from the neonatal rat heart. In conclusion, CAR was expressed abundantly on the whole surface of cardiomyocytes in immature rat hearts. Both the expression level and the localization of CAR are possible determinants of the susceptibility to viral myocarditis of neonates and children. 相似文献
107.
Effects of repeated subculturing and prolonged storage at room temperature of enterohemorrhagic Escherichia coli O157:H7 on pulsed-field gel electrophoresis profiles 下载免费PDF全文
Iguchi A Osawa R Kawano J Shimizu A Terajima J Watanabe H 《Journal of clinical microbiology》2002,40(8):3079-3081
Three clinical strains of enterohemorrhagic Escherichia coli O157:H7 which were subcultured repeatedly or stored at room temperature over a 25-week period showed appreciable variations in their pulsed-field gel electrophoresis fragment patterns. The variations could be explained by a couple of spontaneous genetic events at most and thus did not invalidate the genetic lineage of the strains. 相似文献
108.
Nishioji K Okanoue T Itoh Y Narumi S Sakamoto M Nakamura H Morita A Kashima K 《Clinical and experimental immunology》2001,123(2):271-279
To clarify the role of IP-10 in autoimmune liver diseases, we studied the serum levels of IP-10 in 14 patients with autoimmune hepatitis (AIH), 23 patients with primary biliary cirrhosis (PBC), and 65 patients with chronic viral hepatitis (20 type B and 45 type C). The hepatic expression of IP-10 mRNA and the correlation between the serum levels of IP-10 and clinical parameters were also evaluated. In addition to 20 healthy controls, 16 rheumatoid arthritis (RA) patients were included as an extrahepatic inflammatory disease. The serum level of IP-10 was significantly (P < 0.02) higher in patients with AIH, PBC, and chronic hepatitis B and C than in healthy controls, and it was significantly correlated (P < 0.05) with the serum levels of aspartate aminotransferase and alanine aminotransferase in patients with AIH, PBC, and chronic hepatitis B and C. The serum level of IP-10 was not elevated in RA patients. After successful treatment of AIH and chronic hepatitis C, the serum level of IP-10 decreased to the same level as in healthy volunteers. As we previously showed in cases with chronic hepatitis B or C, in situ hybridization in both AIH and PBC cases demonstrated the expression of IP-10 mRNA in hepatocytes around focal or lobular necrosis surrounded by infiltrating mononuclear cells, whereas IP-10 mRNA was not expressed in areas around the damaged bile ducts in PBC cases. The present results suggest that IP-10 is specifically produced by hepatocytes in inflammatory areas irrespective of the aetiology of hepatitis, and that IP-10 may help to recruit T cells to the hepatic lesions in autoimmune liver diseases as well as in chronic viral hepatitis. 相似文献
109.
Komei Ito Masaki Futamura Yuri Takaoka Masashi Morishita Kumiko Nakanishi Tatsuo Sakamoto 《Arerugī》2008,57(8):1043-1052
Background: A method for open food challenge test to determine food allergy has not been established in an evidence-based manner. Methods: We conducted an analysis of 438 open food challenges of raw milk (n=133, mean age 2.7+/-1.9 years), boiled egg white (n=216, 2.8+/-2.1 years) or udon noodles (n=89, 2.7+/-1.7 years) for the patients aged 1 year or more. Doses were increased (trace amounts, 1 g, 2 g, 5 g, 10 g, 20-30 g) every 20 minutes. Results: In total, 151 (38.5%) of food challenges were positive. The positive rates of milk, egg and wheat challenges were 35.8%, 42.4% and 33.3%, respectively. Of these, 76.2%, 32.5%, 27.8% and 0.7% had, respectively, skin, respiratory, gastrointestinal and cardiovascular symptoms. Although the prevalence of positive challenge increased with level of specific IgE, it did not correlate with the threshold amount of positive food challenge or the severity of symptoms. Among the challnege positive patients, 10.6% required injection of antihistamines, corticosteroids or adrenalines for the treatment of the symptoms. Conclusions: This challenge protocol seemed to be appropriate and safe. 相似文献
110.
Studies on the osmophilic fungus Wallemia sebi as an allergen evaluated by skin prick test and radioallergosorbent test 总被引:1,自引:0,他引:1
T Sakamoto A Urisu M Yamada Y Matsuda K Tanaka S Torii 《International archives of allergy and applied immunology》1989,90(4):368-372
Recently, Wallemia sebi, a species of osmophilic fungi, has been abundantly detected in house dust using low water activity media. In this study, allergenic activity of W. sebi was assessed by skin prick test and radioallergosorbent test (RAST) in 74 asthmatic patients ranging from 6 to 32 years of age. Aspergillus fumigatus and house dust were used for comparison. In skin prick test, W. sebi extract, A. fumigatus extract and house dust extract elicited positive reactions in 4 (5.4%), 4 (5.4%) and 51 (68.9%) patients, respectively. RAST showed positive results in 14 subjects (18.9%) for W. sebi extract, in 8 (10.8%) for A. fumigatus extract and in 59 (79.7%) for house dust extract. These results indicated that some asthmatic individuals showed immediate-type hypersensitivity to W. sebi, and which means this fungal species may be of importance to atopic diseases as a causative agent. 相似文献