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991.
Drs Hideo Tanaka Drs Tomohiko Hiyama Drs Hideaki Tsukuma Drs Yasuto Okubo Drs Hajime Yamano Drs Akira Kitada Drs Isaburo Fujimoto 《Cancer causes & control : CCC》1994,5(5):409-413
To clarify the demographic characteristics of the prevalence of hepatitis C virus (HCV) infection in Osaka, Japan, where hepatocellular carcinoma is common, we investigated the screening data of antibody to HCV (anti-HCV, DAINABOTHCVPHA, second generation assay) in 197,600 voluntary blood donors residing in Osaka. The study found that age-standardized prevalence of anti-HCV was significantly higher than that of HBsAg (2.25cf 0.86 percent among males,P<0.001; 2.17cf 0.55 percent among females,P<0.001. It was much higher in the blood donors aged 55–64 years than in those aged 16–54 years (8.49cf 1.32 percent among males,P<10–5; 7.26cf 1.42 percent among females,P<10–5). The prevalence of anti-HCV among males was significantly higher than that of females in the younger (25–34 years) generations (1.02 to 1.49 percentcf 0.71 to 1.13 percent,P<0.05). A similar tendency was observed in the prevalence of high-titer (212) anti-HCV. The number of coinfection (both HBsAg and anti-HCV seropositive) was very small, and it was not statistically different from the expected number. 相似文献
992.
Chia-Ming Chu MD I-Shyan Sheen MD Chau-Ting Yeh MD Sen-Yung Hsieh MD Sun-Lung Tsai MD Yun-Fan Liaw MD 《Digestive diseases and sciences》1995,40(10):2107-2112
To evaluate the potential implication ofin vivo interferon production in the pathogenesis of different forms of acute and chronic hepatitis B virus infection, serum levels of interferon- and- were measured using immunoassay techniques in 20 patients with acute hepatitis B who subsequently cleared the virus (group Ia), 8 patients with acute hepatitis B who became HBsAg carriers (group Ib), 55 patients with chronic hepatitis B (group II), and 15 healthy controls. None of the controls had interferon- or- detectable in serum, while 15% and 100% of group Ia patients, 25% and 100% of group Ib patients, and 22% and 15% of group II patients, had raised serum levels of interferon- and-, respectively. Serum interferon- was detected significantly more frequently in group Ia and Ib patients than in controls and in group II patients. Among patients with acute hepatitis B, serum levels of interferon- and- showed no significant difference between group Ia and group Ib patients. Among patients with chronic hepatitis B, interferon- was detected significantly more frequently in patients with serum HBV-DNA (31.4% or 11/35) than in those without (5% or 1/20), whereas interferon- was detected significantly more frequently in patients with chronic active hepatitis (28% or 7/25) than in those with chronic persistent hepatitis (3.3% or 1/30). In conclusion, in acute hepatitis B, serum levels of interferon- and- did not show a significant difference between patients who subsequently cleared the virus and those who became HBsAg carriers. In chronic hepatitis B, the raised serum levels of interferon- correlated with the presence of viral replication, while the raised serum levels of interferon- correlated with the presence of histological evidence of active hepatitis. 相似文献
993.
It has been estimated that presently hepatitis B kills more people every day than AIDS kills in a year world-wide. Infection
with hepatitis B produces a wide range of manifestations ranging from asymptomatic carriers to persistent infections leading
to chronic liver diseases and hepatocellular carcinoma. Availability of effective and safe vaccine has made all this preventable.
To formulate on appropriate vaccination strategy for India the epidemiology of hepatitis B needs to be defined. This report
critically reviews the available data. The burden of long term sequelae of HBV infection is probably under-diagnosed and under-reported
in India. Prevalence studies of HBV markers indicate that India falls under the area of intermediate endemicity. Limited data
on agespecific prevalence of HBV markers suggests that the majority of the infection seems to take place below 15 years of
age, and most of it under one year. Perinatal transmission appears to contribute significantly to the carrier pool. Childhood
vaccination for HB among the general population is the obvious strategy of choice. But more information is required to decide
on the timing of the first dose. 相似文献
994.
H. H. F. Derkx E. J. Kuijper C. A. P. Fijen M. Jak J. Dankert S. J. H. van Deventer 《European journal of pediatrics》1995,154(9):735-738
We evaluated the complement system in 29 children (mean age: 4.5 years) who survived fulminant meningococcal septic shock. No terminal complement deficiencies were found. One patient, who experienced the most dramatic disease course, had a decreased haemolytic activity in the haemolytis-in-gel test for the alternative pathway. The properdin concentration in serum of this patient was < 0.1 g/ml (n = 17.1–27.7 g/ml). Coagulation studies revealed a heterozygeous type I protein C deficiency as well. He was the only patient with aNeisseria meningitidis group Y infection. 相似文献
995.
Tumor necrosis factor-{alpha} up-regulates Bcl-2 expression and decreases calcium-dependent apoptosis in human B cell lines 总被引:7,自引:0,他引:7
Genestier Laurent; Bonnefoy-Berard Nathalie; Rouault Jean-Pierre; Flacher Monique; Revillard Jean-Pierre 《International immunology》1995,7(4):533-540
Group I and Epstein–Barr virus-negative Burkitt's lymphomacell lines and the B104 lymphoma cell line which expresses aphenotype of immature B cells undergo apoptosis after cross-linkingof their surface Ig receptors or after exposure to a calciumionophore. We show here that tumor necrosis factor (TNF)- protectsthese B cell lines against Ca2+-dependent apoptosis. Protectionwas associated with up-regulatlon of bcl-2 mRNA and proteinexpression. The increase of Bcl-2 expression induced by TNF-was inhibited by chelerythrine, a specific inhibitor of proteinkinase C (PKC), suggesting that Bcl-2 expression was dependenton PKC activation. Furthermore, we show that phorbol estersand cyclosporin A (CsA), which prevent Ca2+-dependent apoptosis,up-regulated Bcl-2 expression. The effect of CsA on Bcl-2 expressionis controlled by calcineurin since we have shown that FK506but not rapamycin had the same effect on Bcl-2 expression, whereasokadaic acid, an inhibitor of phosphatases 1, 2A and 2C, wasineffective. These data provide direct evidence that TNF- preventsCa2+-dependent apoptosis by a Bcl-2-dependent mechanism mediatedby PKC. 相似文献
996.
Wright Jennifer D. Ma Tianwei Chu Chung K. Boudinot F. Douglas 《Pharmaceutical research》1995,12(9):1350-1353
Purpose. The objective of this study was to characterize the pharmacokinetics of 1 -(2-deoxy-2-fluoro--L-arabinofuranosyl)-5-methyluracil (L-FMAU), a nucleoside analogue with potent activity against the hepatitis B virus and the Epstein-Barr virus, in rats.
Methods. Three doses of L-FMAU were administered intravenously (10, 25, and 50 mg/kg) to rats, and L-FMAU concentrations in plasma and urine were measured by HPLC. Pharmacokinetic parameters were generated by using area-moment analysis.
Results. There were no significant differences in the pharmacokinetic parameters between the three doses ( < 0.05). Thus, the disposition of L-FMAU was linear over the dosage of 10 to 50 mg/kg. Plasma concentrations of L-FMAU declined rapidly with a terminal phase half-life of 1.33 ± 0.45 h (mean ± SD). Total clearance of L-FMAU was moderate, averaging 1.15 ± 0.28 L/h/kg. The fraction of compound excreted unchanged in urine was 0.59 ± 0.13. No glucuronide metabolite was found in the urine. The steady-state volume of distribution was 1.12 ± 0.26 L/kg indicating intracellular distribution of the compound. The fraction of L-FMAU bound to plasma proteins was approximately 15% and was independent of nucleoside concentration.
Conclusions. The pharmacokinetics of L-FMAU in rats were independent of dose over the dosage range of 10 to 50 mg/kg. 相似文献
997.
Recombinant {alpha}-interferon in renal allograft recipients with chronic hepatitis C 总被引:5,自引:0,他引:5
Ozgur O.; Boyacioglu S.; Telatar H.; Haberal M. 《Nephrology, dialysis, transplantation》1995,10(11):2104-2106
BACKGROUND.: Although chronic hepatitis C infection is one of the factorsthat can lead to morbidity and mortality in renal allograftrecipients, treatment procedures have not been well documented.Interferon treatment has been shown to be effective in the normalizationof biochemical hepatitis C and in the clearing of hepatitisC virus RNA. However, little is known concerning the efficacyand safety of interferon treatment in renal allograft recipientswith chronic hepatitis C. Interferon has also been accused ofincreasing renal allograft rejection. METHODS.: Recombinant -interferon in a dose of 4.5 million units threetimes per week was given to five renal-allograft recipientswith chronic hepatitis C for 6 months. Besides biochemical investigations,liver histopathologies before and after the treatment coursewere also studied. RESULTS.: Interferon treatment was effective in two of the patients, inanother two cases renal function deteriorated during the treatment.In the last case ALT increased again after cessation of interferontherapy. CONCLUSION.: We conclude that interferon seems to be moderately effectivein treating chronic hepatitis C in renal allograft recipients,but a risk of renal functional deterioration and rejection remains. 相似文献
998.
Wan-Wan Lin 《Naunyn-Schmiedeberg's archives of pharmacology》1995,352(6):679-684
To investigate the role of calmodulin (CaM)-dependent pathways in agonist-induced phosphoinositide (PI) turnover, the influence of several CaM antagonists on PI-phospholipase C (PLC) activation in intact and permeabilized C6 glioma cells was examined. The extent of PI turnover was assessed by measuring the accumulation of inositol phosphates (IPs) in the presence of LiCl in C6 glioma cells prelabelled with myo-[3H]inositol. Trifluoperazine, N-(6-aminohexyl)-5-chloro-l-naphthalenesulphonamide (W7), fendiline and calmidazolium themselves had no effect on basal IP formation, but concentration-dependently (1–30 M) potentiated ATP-, NaF- and A23187-stimulated IP formation. The maximal response to ATP (I mM) was increased by up to 50%, while the concentration for half-maximal effect (EC50, 60 M) as unaffected by trifluoperazine. In digitonin-permeabilized C6 glioma cells, the concentration-dependent increase of PI-PLC activation elicited by free Ca2+ was potentiated by the GTP analogue, guanosine 5-[-thio]triphosphate (GTPS), with an EC50 of 6 M. Trifluoperazine (1–30 M) enhanced the Ca2+-stimulated IP formation concentration dependently and this potentiation was counteracted by the addition of CaM. In the combined presence of each CaM antagonist studied and GTPS, an additive increase in IP formation was observed. The results indicate that CaM antagonists enhance stimulus-induced IP formation in C6 glioma cells primarily by increasing the Ca2+-dependent activation of PI-PLC. 相似文献
999.
I. Ieiri W. Goto S. Higuchi K. Hirata A. Toshitani S. Imayama Y. Ohyama H. Yamada K. Ohtsubo 《European journal of clinical pharmacology》1995,49(1-2):51-56
The purpose of this study was to assess the possible role of the (R)- and (S)- enantiomers of the phenytoin metabolite p-HPPH in the pathogenesis of gingival hyperplasia (GH). About 98% of circulating p-HPPH is in the (S)-form. There were significant differences between patients with and without GH in (R)-p-HPPH level (0.055 vs 0.042 g·ml–1), both enantiomer/racemate level ratios, and R/S enantiomeric ratio (0.0313 vs 0.0232); an increase in serum (R)-p-HPPH level was observed in patients with GH. In separate experiments, the effect of p-HPPH enantiomers on the proliferation of the normal human dermal fibroblast was studied. The in vitro study showed that (R)-p-HPPH selectively stimulated fibroblast growth. The results suggest that the least abundant metabolite, (R)-p-HPPH, is the most toxic with respect to gingival hyperplasia. 相似文献
1000.
447C88 (N-Heptyl-N-(2,4 difluoro-4-6-(2(-4-(2,2 dimethylpropyl)phenyl)ethyl)phenyl)urea) is an inhibitor of human microsomal AcylCoA:Cholesterol acyltransferase (ACAT) with an IC50 of 10.2 ng·ml–1 (23 nM). It is poorly absorbed but 5 mg·kg–1·day–1 completely abolishes the rise in plasma cholesterol in cholesterol-fed rats.In this study, twelve healthy, male volunteers received single, oral doses of 25, 50, 100, 200, 400 and 800 mg of 447C88 (n+8) or placebo (n+4) with food in a double-blind study with at least a week between occasions. The 400 mg dose was repeated after an overnight fast. Subsequently, fourteen different volunteers received a single 200 mg dose of 447C88 (n+8) or placebo (n+6) with food and, a week later, the same dose twice daily for 10 days; all doses were given with food.All doses were well tolerated with no significant changes in vital signs, full blood counts or plasma biochemical profiles. Plasma concentrations of 447C88 were unquantifiable after the fasting dose and low after all other doses. Mean Cmax and AUC were 1.8 ng·ml–1 and 9.0 ng·ml–1·h after 200 mg rising to 5.4 ng·ml–1 and 23.8 ng·ml–1·h respectively after 800 mg; t1/2 was 1.3 to 5.2 h. After 10 days dosing, plasma 447C88 concentrations were higher in the evening than the morning probably due to administration of the evening dose with more food. There were no significant changes in plasma triglcerides or total, LDL- or HDL-cholesterol after dosing with 447C88. 相似文献