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991.
Kinetics of the hepatitis C virus during interferon therapy as a marker of therapeutic response 总被引:2,自引:0,他引:2
Nakamuta M Fukutomi T Shimohashi N Kinukawa N Uchimura K Tada S Motomura K Enjoji M Kato M Iwamoto H Tanabe Y Imari Y Sakamoto S Sakai H Nawata H 《Journal of gastroenterology and hepatology》2001,16(1):29-33
BACKGROUND: The viral load and subtype of hepatitis C virus (HCV) are predictors of the efficacy of interferon (IFN) therapy. The kinetics of HCV during IFN therapy have been described recently, suggesting that HCV infection is highly dynamic. These observations have raised the issue as to whether early monitoring of the viral load can help guide IFN therapy. METHODS: We measured HCV-RNA levels at 0, 24 and 48 h after the start of IFN-alpha treatment (10 MU daily for 2 weeks and then three times weekly for 22 weeks) or IFN-beta treatment (6 MU daily for 6 weeks). Then we analyzed the relationship between HCV kinetics and therapeutic response using stepwise multivariate logistic regression analysis. RESULTS: The exponential decay slope of the viral load during the first 24 h, not the first 48 h or the next 24 h, was a predictor of viral eradication at 6 months after completion of the treatment (sustained response; P = 0.0023). This decay slope was not affected by the HCV serotype or the type of IFN used. Initial viral load and HCV serotype were also predictors, as reported previously (P < 0.0001 and P = 0.0347, respectively). We also proposed a model using a prognostic index that predicted a sustained response with more than 80% sensitivity, specificity and efficacy in an independent and external group of patients. CONCLUSION: This study demonstrated that the exponential decay slope of the viral load during the first 24 h was an important predictor of the response to IFN therapy as well as the initial viral load and HCV serotype. The model may also be useful for the clinical management of IFN therapy. 相似文献
992.
993.
Tanaka K Kiyohara Y Kato I Matsumoto T Yamagata H Kubo M Tanizaki Y Okubo K Nakamura H Iwamoto H Nakayama K Iida M 《Scandinavian journal of gastroenterology》2004,39(5):459-463
BACKGROUND: No population-based cohort studies have been undertaken to evaluate the incidence and prognosis of gastric cancer. The purpose of this investigation was to clarify the incidence and fatal prognosis of gastric cancer and to determine the factors that contribute to the prognosis in a general Japanese population in Hisayama using a prospective study design. METHODS: From 1988 to 1998 a total of 2605 subjects aged 40 years or older with no history of gastrectomy or gastric cancer were followed-up prospectively after a health examination. The diagnosis of gastric cancer was based on clinical records or autopsy findings. RESULTS: During the follow-up period, 76 subjects developed gastric cancer. The age-adjusted incidence of gastric cancer for men (4.9 per 1000 person-years) was 4-fold higher than that for women (1.2, P < 0.05). In men, the incidence of gastric cancer increased with advancing age, but this trend was not observed in women. The age- and sex-adjusted 5-year survival rate was significantly higher in cancers of the middle third of the stomach than in those of the upper third of the stomach. The survival rate was higher in cancers of well-differentiated adenocarcinoma than in those of the other histological types. There were no cases of cancer-related death among the early gastric cancers during the follow-up period. CONCLUSIONS: Our data suggest that men are at higher risk of gastric cancer than women in the general Japanese population. Clinical stage, histological type, and site of cancer in the stomach contribute to a fatal prognosis. 相似文献
994.
Masunaga R Nagasaka A Sawai Y Hayakawa N Nakai A Hotta K Kato Y Hishida H Takahashi H Naka M Shimada Y Tanaka T Hidaka H Itoh M 《Journal of molecular and cellular cardiology》2004,37(3):767-774
Cyclic nucleotides (cAMP and cGMP) phosphodiesterase (PDE) activities and expression are altered in the cardiac muscle of cardiomyopathic heart failure, and PDE inhibitors improve the abnormal muscle condition through changing the cyclic nucleotide concentration. These observations prompted us to investigate the role of calmodulin (CaM) in the regulation of cyclic nucleotide PDE activities, and moreover to study the modulation of the PDE isozymes in heart failure, using cardiac muscles of cardiomyopathic hamster. The CaM concentrations in the heart muscle of the normal control and cardiomyopathic hamsters (each of three to four hamsters) varied with cell fraction and with the age of the animal. The CaM concentrations in the soluble fraction obtained from cardiomyopathic hamster tissue were significantly increased at 25 and 32 weeks of age (2.02 +/- 0.62 microg/mg protein (mean +/- S.E.), and 3.21 +/- 0.95) compared with that obtained from the control (0.60 +/- 0.04) or cardiomyopathic (0.95 +/- 0.12) hamsters at 8 weeks of age. The solubilized PDE isolated from the hamster heart muscle (three or four hamsters in each age) by column chromatography on diethylaminoethyl (DEAE)-cellulose revealed three peaks of activity, which may correspond to the isozymes of PDE classified recently, namely PDE I, II, and III. These three peaks of activity, particularly peak III, seen in the soluble fraction of cardiomyopathic hamster heart declined in proportion to the age of the animal compared with that of the control hamster heart. In the cGMP-PDE assay system, the concentration of CaM inhibitor W-7 required for 50% inhibition (IC(50)) of PDE I, II, and III peak activities was 140, 29, and 46 microM, respectively, suggesting that PDE II is more sensitive to W-7. These results suggest that alteration in these isozyme activities accompanied with changes of CaM concentration may influence the cardiac muscle contractility in cardiomyopathic hamster via changes of cyclic nucleotide concentration. 相似文献
995.
Nakano I Tsugawa T Shinohara R Watanabe F Fujita T Nagata M Kato T Himeno Y Kobayashi T Fujiwara K Nagata M Itoh M Nagasaka A 《Journal of diabetes and its complications》2003,17(6):337-342
The amounts of sorbitol (SOR) excreted in 24-h urine were determined on two groups, i.e., diabetic and nondiabetic patients, using an improved method in which ion exchange resin column processing was applied, and these levels were compared with SOR levels in whole blood. Urinary SOR concentration was also determined in diabetic and normal rats in the same manner and its relationship to aldose reductase (AR) activity in whole blood was investigated. Changes in SOR levels in urine and whole blood were compared in diabetic rats after administration of an AR inhibitor (ARI). Whole blood SOR levels and urinary SOR excretion were significantly higher in diabetic patients than in nondiabetic patients. The same results were obtained in the animal models. In diabetic rats, the urinary SOR excretion was about five times higher than that in control rats, and the AR activity in whole blood was also significantly higher. The increase in urinary SOR excretion and whole blood SOR levels, as well as AR activity, in blood in the diabetic state was inhibited by ARI administration. The influence of the diabetic state and the efficacy of the ARI were more marked in urinary SOR excretion than in whole blood SOR levels. These data indicate that determinations of urinary SOR excretion and AR activity are easily measurable and of benefit to assessing the diabetic condition. 相似文献
996.
Prevalence of diabetes mellitus in Japanese patients infected chronically with hepatitis C virus 总被引:11,自引:0,他引:11
Arao M Murase K Kusakabe A Yoshioka K Fukuzawa Y Ishikawa T Tagaya T Yamanouchi K Ichimiya H Sameshima Y Kakumu S 《Journal of gastroenterology》2003,38(4):355-360
Background: To examine the relationship between hepatitis C virus (HCV) infection and diabetes mellitus (DM) in Japanese populations,
a retrospective study was done in 866 patients with chronic viral disease. Methods: The present study included 707 HCV-infected and 159 hepatitis B virus (HBV)-infected patients. The prevalences of HBV- and
HCV-related cirrhosis were 32% and 33%, respectively. A case-control study was also conducted to determine the seroprevalence
of HCV infection in a cohort of 459 diabetics. Results: The prevalence of DM was higher in HCV-infected patients (20.9%; P < 0.02) than in HBV-infected subjects (11.9%). In the cirrhotic patients, DM was observed in 30.8% of the subjects with HCV
compared with 11.8% of those with HBV (P < 0.01). Multivariate analysis revealed that the major independent variables associated with type II DM were male sex (odds
ratio, 1.54; p = 0.020) and cirrhosis (odds ratio, 1.97; P = 0.0007). The relative odds of the development of DM were calculated to be 3.2 times higher in HCV-infected cirrhotic patients
than in HBV-infected ones. In the case-control study of the diabetic cohort, 10.5% of patients were infected with HCV compared
with 1.1% with HBV (P < 0.0001). The results indicate that HCV infection is closely associated with DM, compared with HBV infection. Cirrhosis
was an independent risk factor for DM. Conclusions: Taken together, the findings indicate that cirrhosis appears to be a more important predictor of glucose intolerance than
HCV infection, and the combination of both factors increases the risk of DM in our populations.
Received: April 18, 2002 / Accepted: October 25, 2002
Reprint requests to: S. Kakumu 相似文献
997.
Epidemiologic and virologic characteristics of hepatitis B virus genotype B having the recombination with genotype C 总被引:32,自引:0,他引:32
Sugauchi F Orito E Ichida T Kato H Sakugawa H Kakumu S Ishida T Chutaputti A Lai CL Gish RG Ueda R Miyakawa Y Mizokami M 《Gastroenterology》2003,124(4):925-932
BACKGROUND & AIMS: Hepatitis B virus (HBV) isolates of genotype B (HBV/B) with or without the recombination with genotype C over the precore region plus core gene have been reported. METHODS: All the 41 HBV/B isolates having the recombination with genotype C (HBV/Ba) possessed the nucleotide 1838 of A in contrast to that of G in all 29 of those without the recombination (HBV/Bj). Taking advantage of this single nucleotide polymorphism, a restriction fragment length polymorphism method was developed that distinguished HBV/Ba from HBV/Bj. RESULTS: HBV/Bj was detected in 90 of the 97 (93%) carriers of HBV/B from Japan, whereas HBV/Ba occurred in all 177 carriers of HBV/B from other countries (China, 20; Hong Kong, 45; Taiwan, 32; Thailand, 30; Vietnam, 30; and the United States, 20 [all of an Asian ethnicity]). In a case-control study, hepatitis B e antigen (HBeAg) and the double mutation in the core promoter (T1762/A1764) were significantly more frequent in 80 carriers each of HBV/Ba than HBV/Bj (35% vs. 18%, P < 0.05 and 33% vs. 15%, P < 0.05, respectively). Differences in the prevalence of HBeAg were more conspicuous between the carriers of HBV/Bj and HBV/Ba older than 30 years (5 of 66 or 8% vs. 16 of 62 or 26%, P < 0.01). CONCLUSIONS: HBV/B having the recombination with genotype C is frequent in Asia, except in Japan, and HBeAg is more prevalent in carriers of HBV/Ba than HBV/Bj. 相似文献
998.
Kuwahara F Kai H Tokuda K Takeya M Takeshita A Egashira K Imaizumi T 《Hypertension》2004,43(4):739-745
Excessive myocardial fibrosis deteriorates diastolic function in hypertensive hearts. Involvement of macrophages is suggested in fibrotic process in various diseased situations. We sought to examine the role of macrophages in myocardial remodeling and cardiac dysfunction in pressure-overloaded hearts. In Wistar rats with suprarenal aortic constriction, pressure overload induced perivascular macrophage accumulation and fibroblast proliferation with a peak at day 3, decreasing to lower levels by day 28. Myocyte chemoattractant protein (MCP)-1 mRNA was upregulated after day 1, peaking at day 3 and returning to insignificant levels by day 28, whereas transforming growth factor (TGF)-beta induction was observed after day 3, with a peak at day 7, and remained relatively elevated at day 28. After day 7, concentric left ventricular (LV) hypertrophy developed, associated with reactive fibrosis and myocyte hypertrophy. At day 28, echocardiography showed normal LV fractional shortening but decreased ratio of early to late filling wave of transmitral Doppler velocity, and hemodynamic studies revealed elevated LV end-diastolic pressure, suggesting normal systolic but impaired diastolic function. Chronic treatment with an anti-MCP-1 monoclonal neutralizing antibody inhibited not only macrophage accumulation but also fibroblast proliferation and TGF-beta induction. Furthermore, the neutralizing antibody attenuated myocardial fibrosis, but not myocyte hypertrophy, and ameliorated diastolic dysfunction without affecting blood pressure and systolic function. In conclusion, roles of MCP-1-mediated macrophage accumulation are suggested in myocardial fibrosis in pressure-overloaded hearts through TGF-beta-mediated process. Inhibition of inflammation may be a new strategy to prevent myocardial fibrosis and resultant diastolic dysfunction in hypertensive hearts. 相似文献
999.
Although it has been well documented that pre-eclampsia is caused by a combination of maternal and fetal susceptibility genes, little is known about the precise etiology of this complicated disorder. To investigate how the expression of fetal genes contributes to the mechanisms underlying the progression of this disease, we have analyzed differentially expressed genes using placentas from 13 normal pregnancies and 14 pregnancies with severe pre-eclampsia. We performed genome-wide expression profiling using high-density oligonucleotide microarrays, followed by validation using real-time PCR. Among the 47,000 genes that were screened in the microarray, 137 genes were found to be differentially expressed between normal and pre-eclamptic tissues. Among these candidates, 70 were up-regulated and 67 were down-regulated. The up-regulated genes included leptin and inhibin A, which are well-known biological markers for pre-eclampsia, as well as FLT1, which was recently proved to be tightly linked with the etiology of this disease. Gene ontology analysis further revealed several biological processes that could be associated with the development of pre-eclampsia, including response to stress, host-pathogen interactions, lipid metabolism, and carbohydrate metabolism. Analyses of biological mechanisms highlighted some important pathways that may be involved in this disorder, such as the TGF-beta and CEBPA-related pathways. Furthermore, when our present subjects were classified as either severe cases of early onset or late onset pre-eclampsia, the expression of 11 genes could be correlated with the severity of this disorder. These genes may therefore prove to be novel biological markers by which the severity of this condition could be predicted. Our data are likely to be a useful future resource in the elucidation of the disease-process and in the identification of novel markers for pre-eclampsia. 相似文献
1000.
Kato T Yamada K Inagaki H Kogo H Ohye T Emanuel BS Kurahashi H 《Fertility and sterility》2007,88(5):1446-1448
We analyzed de novo constitutional t(11;22) translocation frequency in sperm derived from normal healthy males as a function of the age of the sperm donors (from 25 to 51). Translocation-specific polymerase chain reaction demonstrated no age-dependent increment in the frequency of the rearrangements. 相似文献