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101.
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We investigated the localization of hepatitis B virus (HBV) antigens and HBV DNA in dark reddish patchy markings (DRPM) on the hepatic surface in three patients with chronic active hepatitis B. The number of hepatitis B core antigen-positive hepatocytes in areas of DRPM was less than that in areas not appearing as DRPM. The grain concentration indicating HBV DNA on autoradiography in hepatocytes in areas of DRPM was less than that in areas not appearing as DRPM. These findings suggest that replication of the hepatitis B virus is reduced in pre-nodular lesions which are appearing as DRPM in chronic active hepatitis.  相似文献   
103.
ABSTRACT— The expression of intercellular adhesion molecule-1 (ICAM-1) on the hepatocyte membrane was studied in 27 patients with chronic hepatitis B and C (CHB, CHC) by immunostaining using a monoclonal antibody. ICAM-1 was expressed focally in a honeycomb-like pattern by hepatocytes in livers of 26/27 patients. The degree of ICAM-1 expression was closely related to the ALT level and the histological grade of liver damage. Abundant cytotoxic T cells (CD8 +, CD11b –) were found in ICAM-1-positive areas of the liver. Zones of focal necrosis contained both ICAM-1-positive hepatocytes and cytotoxic T cells. The expression of ICAM-1 was decreased in 4/6 CHB patients after interferon-α therapy. No relationship between the degree of hepatocyte ICAM-1 expression and viral replication markers (DNA polymerase activity and the presence of HBcAg in the liver) was observed in patients with CHB. In addition, no positive correlation was found between the distribution of ICAM-1-positive hepatocytes and HBcAg-positive hepatocytes. These results suggest that ICAM-1 may play an important role in the pathogenesis of hepatocellular injury mediated by cytotoxic T cells in CHB and CHC.  相似文献   
104.
Clinical characteristics of autoimmune hepatitis in older aged patients.   总被引:2,自引:0,他引:2  
BACKGROUND AND AIMS: Autoimmune hepatitis (AIH) is an inflammatory disease of the liver that usually develops in middle-aged women. However, due to the increasing aging of the population and better diagnostic facilities, AIH is now diagnosed in older patients as well. This analysis compared the clinical and pathologic characteristics of older and middle-aged patients with AIH. PATIENTS AND METHODS: Thirteen older patients with AIH (mean age, 75.0+/-5.3 years; range, 70-89 years) and 27 middle-aged patients (mean age, 51.3+/-5.8 years; range, 41-60 years) were included in this study. In addition, the use of different treatment regimens, including prednisolone therapy and ursodeoxycholic acid (UDCA), was examined. RESULTS: There were no significant differences in gender, complications of other autoimmune diseases, and liver function tests between groups. However, the degree of hepatic fibrosis was significantly higher in older patients compared with middle-aged patients (P<0.05). Four patients with AIH in the older age group were successfully managed by UDCA alone. CONCLUSION: This study shows that older patients with abnormal liver function should be checked for AIH. In addition, UDCA may be an effective drug for management of older patients with AIH.  相似文献   
105.
BACKGROUND: The inhibition of nitric oxide (NO) exerts injurious effects on the cardiovascular system by several mechanisms, such as the activation of the renin-angiotensin system, oxidative stress, and inflammatory cytokines. We examined whether COX-2, an inducible isoform of cyclooxygenase, is associated with the pathogenesis observed in N(omega)-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats. METHODS: Three groups of 8-week-old male Sprague-Dawley rats were studied (n = 6 in each group): group 1, untreated controls; group 2, treated with L-NAME (1 g/l for 3 weeks, p.o.); and group 3, L-NAME co-treated with COX-2 inhibitor NS-398 (5 mg/kg per day, i.p.). The L-NAME-induced expression of COX-2 mRNA and protein was semi-quantified in the kidneys and the thoracic aorta. Urinary excretion of the prostaglandin 6-keto PGF(1alpha), thromboxane B2 (TXB2), and prostaglandin E2 (PGE2) was measured in the three groups. Moreover, urinary excretion of 8-iso-PGF(2alpha), a potent vasoconstricting arachidonic acid metabolite acting through thromboxane A (TXA) receptor activation, proposed recently as a marker of oxidative stress, was also measured. RESULTS: L-NAME induced significant increases in systolic blood pressure (P< 0.01), urinary protein (P< 0.05), and renal excretion of 8-iso-PGF(2alpha)(P< 0.01), compared with the control. In L-NAME-treated rats, the levels of COX-2 mRNA and protein were more than 50% higher in the kidneys (P< 0.05), and six-fold higher in the thoracic aorta (P< 0.01) than in control rats. NS-398 significantly ameliorated an increase in systolic blood pressure (P< 0.01) and urinary protein (P< 0.05) induced by L-NAME. CONCLUSIONS: These data indicate that an increase in COX-2 expression might have a hypertensive effect, partly associated with 8-iso-PGF(2alpha) formation in l-NAME-treated rats.  相似文献   
106.
Summary To identify the K+ channels responsible for endothelium-derived hyperpolarizing factor (EDHF)-dependent relaxation, we studied the effects of various K+ channel blockers on acetylcholine-induced relaxation, which persists even in the presence of both an inhibitor of nitric oxide synthase and that of cyclooxygenase, in canine coronary artery rings. A nonselective K+ channel blocker, tetrabutylammonium (TBA), a large and intermediate conductance Ca2+-activated K+ channel blocker, charybdotoxin (CTX), and a voltage-dependent K+ channel blocker, 4-aminopyridine (4-AP), significantly inhibited this residual relaxation. A combined treatment with CTX and 4-AP almost completely blocked the relaxation. Neither a large (iberiotoxin) nor a small (apamin) conductance Ca2+-activated K+ channel blocker blocked the relaxation. We also investigated effects of K+ channel blockers on basal tone to determine whether or not EDHF is involved in regulating basal tone. TBA and CTX substantially raised basal tone to a greater degree in endothelium-intact preparations than in endothelium-denuded preparations. These results indicate that EDHF may exert its relaxing action through intermediate conductance Ca2+-activated and voltage-dependent K+ channels in canine coronary arteries. In addition, EDHF may play a role in maintaining basal vascular tone. This study was supported in part by a Grant-in-Aid for Scientific Research (B07457167) from the Ministry of Education, Science and Culture of Japan.  相似文献   
107.
We have evaluated the usefulness of off-pump coronary artery bypass grafting (CABG)[OPCAB]. The subjects were 153 patients who underwent isolated CABG between May 2005 and May 2009. They were divided into 2 groups( on-pump/arrest;ON group:76 subjects vs OPCAB;OFF group:77 subjects). The concomitant conditions, the number of bypasses, the postoperative outcome and the early graft patency rate were compared between the 2 groups. The mean age and the incidence of carotid artery lesions were significantly higher in the OFF group. The number of bypasses was significantly smaller in the OFF group. The postoperative intubation time and the length of postoperative hospitalization were significantly shorter in the OFF group. Concerning major postoperative complications, mediastinitis, cerebral infarction or bleeding was not observed in the OFF group. There was no hospital death in the OFF group. The early graft patency rate with saphenous vein graft (SVG) was significantly lower in the OFF group. Early stage extubation was achieved by the introduction of OPCAB. In some occasions, however, the target site could not be reached with OPCAB, and furthermore, the quality of anastomosis was poor. In order to achieve complete revascularization, therefore, on-pump/arrest surgery should be considered in some cases.  相似文献   
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PURPOSE: Only a few studies have been reported on CTL epitope peptides restricted with alleles other than HLA-A2 and -A24. The HLA-A11, -A31, and -A33 alleles share similar binding motifs with HLA-A3 and -A68 alleles, and, thus, are classified as an HLA-A3 supertype. This study tried to identify CTL epitope peptides as vaccine candidates sharing by HLA-A3(+), -A11(+), -A31(+), and -A33(+) cancer patients. EXPERIMENTAL DESIGN: Seven peptides possessing the ability to induce HLA-A31-restricted and tumor-reactive CTLs were examined for their ability to induce HLA-A3-, -A11-, and -A33-restricted and tumor-reactive CTLs from peripheral blood mononuclear cells (PBMCs) of 18 epithelial cancer patients. The five reference peptides all have the ability to induce CTL activity restricted with one of the HLA-A3 supertypes, and, thus, were also examined as positive controls. RESULTS: Three peptides (2 from beta-tublin5- and 1 from CGI37-derived peptides) induced tumor-reactive CTLs in PBMCs of HLA-A3(+), -A11(+), and -A33(+) cancer patients with various frequencies (17-50%). One RLI- or KIAA0036-derived peptide induced tumor-reactive CTLs in PBMCs of HLA-A3(+) and -A11(+) or HLA-A11(+) and -A33(+) cancer patients also with various frequencies (22-67%), respectively, whereas the other peptide induced CTL activity in only HLA-A33(+) patients. Among the five reference peptides tested, one peptide, TRP2-197, induced CTL activity in both HLA-A11(+)- and -A33(+)-restricted manners. CONCLUSIONS: We identified new peptide vaccine candidates for HLA-A3, -A11, -A31, and -A33 positive cancer patients. This study may facilitate the development of both basic and clinical studies of peptide-based immunotherapy for cancer patients with other alleles of HLA-A2 and -A24.  相似文献   
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