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1.
To evaluate the profile of hepatitis D virus replication and the corresponding immunoresponse after acute hepatitis D virus infection, sera from 50 patients with acute hepatitis D (36 with acute hepatitis B virus-hepatitis D virus coinfection and 14 HBsAg carriers with hepatitis D virus superinfection) were investigated for the presence of hepatitis D virus RNA and other serological hepatitis D virus markers. During the first week after onset of symptoms, hepatitis D virus RNA was detected by spot hybridization with a similar frequency among patients with coinfection (64%) and those with superinfection (71%). The presence of hepatitis D virus RNA in the first serum sample correlated with that of circulating hepatitis D antigen in both groups of patients. The presence of hepatitis D virus RNA was transient and its clearance paralleled that of serum hepatitis D antigen among patients with coinfection, so that 1 month after the onset of symptoms serum hepatitis D virus RNA was no longer detectable in any of these patients. Conversely, serum hepatitis D virus RNA was still present in 78% of those with superinfection, all of whom developed chronic liver disease, thus suggesting that the persistence of hepatitis D virus RNA in the serum for more than 4 weeks might indicate progression to chronicity. In nine of the 14 patients (64%) with hepatitis D virus superinfection progressing to chronicity, hepatitis D virus RNA was persistently detected throughout the follow-up, whereas in five patients it was detected occasionally. In four superinfected patients hepatitis D virus RNA and hepatitis B virus DNA were detected simultaneously in serial samples, thus suggesting that, at least during early stages of chronic hepatitis D virus infection, both viruses may replicate at the same time.  相似文献   
2.
To determine whether a dramatic decrease in hepatitis B virus (HBV) DNA levels within the first months of lamivudine therapy can predict the emergence of YMDD variants in patients with chronic hepatitis B, quantitative testing was done every 3 months on serum samples from 35 patients who were treated with lamivudine for >1 year. The decline in HBV DNA levels from baseline to month 3 was higher in 22 responders than in 13 nonresponders (mean+/-SD, 4.16+/-1.06 vs. 2.88+/-1.77 log(10) copies; P=.002), whereas no differences were observed in patients with and without YMDD variants at 1 year of therapy. At 3 months, HBV DNA was undetectable in 77% of the responders, whereas, after 1 year, it was undetectable in 23% of nonresponders, 40% of patients with YMDD variants, and 74% of those without variants. Therefore, quantitative HBV DNA testing is very useful in deciding whether to continue therapy, because of the low likelihood of response in patients who remain HBV DNA positive at month 3 of treatment.  相似文献   
3.
BACKGROUND: The glutathione S-transferase P1 (GSTP1) gene is involved in detoxification of electrophilic substances of tobacco smoke. A polymorphism at nucleotide 315 of this gene alters its enzymatic activity. OBJECTIVE: We analyzed the association between the variability in the GSTP1 gene and impairment in lung function in smokers with and without alpha(1)-antitrypsin (AAT) deficiency and COPD.Population and method: The study population consisted of 99 patients with smoking-related COPD and 69 patients with AAT deficiency; 198 healthy volunteers provided the frequency of the different polymorphisms in the general population. GSTP1 genotyping was performed by a real-time polymerase chain reaction amplification assay. RESULTS: The frequency (0.28) of the 105Val polymorphism was identical in COPD patients and the general population. However, the frequency was significantly increased (0.44) in patients with AAT deficiency (odds ratio [OR], 2.09; 95% confidence interval [CI], 1.17 to 3.72 compared to control subjects; and OR, 2.41; 95% CI, 1.27 to 4.59 compared to COPD). FEV(1) percentage of predicted was significantly impaired in AAT-deficient carriers of 105Val. This effect was not observed in COPD patients. CONCLUSIONS: These findings suggest that the frequency of the GSTP1 105Val polymorphism is increased in patients with AAT deficiency. Globally, GSTP1 genotypes, age, and tobacco smoking explained 41% of total FEV(1) percentage of predicted variability in patients with AAT deficiency. The modulatory role of GSTP1 in lung disease has only been observed in smokers lacking AAT.  相似文献   
4.
5.
BackgroundData concerning the outcome of lamivudine-resistant (LAM-R) chronic hepatitis B (CHB) patients with compensated cirrhosis under adefovir (ADV) treatment are limited. The aim of our study was to evaluate the medium term outcome of these, high-risk for fatal events, patients.Methods31 LAM-R patients with compensated cirrhosis who had been treated with ADV monotherapy (n = 8) or ADV plus LAM (n = 23) for a mean of 27.6 months, were evaluated. Virological response (VR) was defined as HBV-DNA levels < 104 copies/ml within the first year of treatment.ResultsTwenty-three patients (74.19%) achieved VR. Six patients (19.35%) developed ADV-related mutations (annual incidence 11%). Liver-related death, liver decompensation and hepatocellular carcinoma (HCC) were observed in 12.9%, 16.12% and 16.12% of patients, respectively. HCC (annual incidence 9.1%) was the main cause of liver decompensation (4/5, 80%) and of liver-related deaths (3/4, 75%). HCC development was not related to patients' age (p = 0.440), HBeAg status (p = 0.245), HBV genotype (p = 0.598), baseline ALT levels (p = 0.981), baseline viral load (p = 0.464), VR (p = 0.504) as well as emergence of ADV resistance (p = 0.871).ConclusionsADV suppresses viral replication in more than 70% of LAM-R cirrhotic patients during the first year of treatment. Despite that, HCC is frequently observed in these high-risk patients, irrespective of virological response or emergence of ADV resistance.  相似文献   
6.
The use of dried blood spot (DBS) specimens in quantitative alpha1-antitrypsin (alpha1-AT) detection or genetic analysis is limited because protein levels in the samples are low and they contain components that can interfere with polymerase chain reaction amplification. A methodological adaptation was developed to overcome these drawbacks which is discussed here. The study population consisted of 200 healthy volunteers and 300 patients with chronic obstructive pulmonary disease (COPD). DBS specimens were tested for alpha1-AT concentration using a modified nephelometric assay and phenotyped with an isoelectric focusing method. Genetic diagnosis was established by deoxyribonucleic acid sequencing using a simple purification procedure to remove contaminants. The nephelometric method showed a detection limit of 0.284 mg x dL(-1), corresponding to a serum concentration of 13 mg x dL(-1). The correlation coefficient between alpha1-AT concentrations in DBS versus serum samples was R2=0.8674 (p<0.0001). All 200 healthy individuals had DBS alpha1-AT concentrations >1.9 mg x dL(-1), corresponding to 114 mg x dL(-1) in serum samples. One hundred and twenty-five COPD patients (42%) showed alpha1-AT values <1.8 mg x dL(-1). Twenty patients with the PIZ phenotype had alpha1-AT values lower than 0.64 mg x dL(-1). On the basis of genotyping, one COPD patient was classified as heterozygous (PIMM(heerlen)). Selective elution of contaminants resulted in optimal alpha(1)1-antitrypsin genotyping. Because of its sensitivity and excellent correlation with the standard method, the dried blood spot quantitative assay is a reliable tool for routine measurement of alpha1-antitrypsin.  相似文献   
7.
Development of hepatitis B virus (HBV)-resistant strains following nucleos(t)ide analog treatment is a major medical concern. This report describes a case of an adult patient with chronic HBV infection, sequentially treated with the nucleos(t)ide analogues, lamivudine, adefovir, and entecavir. During monotherapy with lamivudine, the patient developed lamivudine-resistant variants, which were undetectable during adefovir dipivoxil monotherapy. Twenty-two months after discontinuing lamivudine therapy, the resistant variants were again detected while the patient was receiving entecavir monotherapy. Genotypic analysis by sequencing the HBV polymerase was confirmed with the INNO-LiPA method. The results of this study suggest that entecavir treatment reselected residual lamivudine-resistant HBV variants, possibly because lamivudine-resistant HBV is less susceptible to entecavir than the wild-type virus. Despite the presence of these variants, the patient has had a complete virological response.  相似文献   
8.
The angiotensin-converting enzyme (ACE) gene has been implicated in the manifestation of the phenotype of malignant hypertension (MH). In 1990 the ACE gene polymorphism characterized by the insertion or deletion of a 287-base pair fragment in the 17q23 chromosome was identified. The DD genotype is associated with increased tissue and circulating ACE levels and elevated angiotensin II. ACE polymorphism was studied in 48 patients with MH, 25 patients with non-MH, and a control group of 78 normotensive individuals by real-time polymerase chain reaction using the LightCycler system (Roche Diagnostics Corporation, Indianapolis, IN). The DD genotype was found statistically more frequently in MH patients than controls (p=0.028; odds ratio, 2.5; confidence interval, 1.1-5.5). Presence of the DD genotype of the ACE gene is more frequent in MH patients than in controls, indicating that this genotype could be a significant risk factor and a predictor for the development of MH.  相似文献   
9.
BACKGROUND/AIMS: In industrialized countries hepatitis E virus (HEV) infection is rare and its diagnosis is difficult because the utility of available tests is not well established. METHODS: We studied the presence of acute HEV infection markers in a cluster of 11 cases of acute hepatitis with IgG anti-HEV antibodies. RESULTS: Three cases were confirmed as acute hepatitis E and 8 as presumptive hepatitis E, two as a past HEV infection and one could not be determined. Three different HEV strains were identified in serum from 3 patients. Two strains belonged to genotype 3, the predominant genotype found in local urban sewage and the other strain belonged to genotype 1 and was considered an imported strain. CONCLUSIONS: Our findings demonstrate the presence of some autochthonous, sporadic acute hepatitis E cases as well as an imported case in our area and the transitory nature of virological and serological markers for HEV.  相似文献   
10.
BACKGROUND/AIMS: Chronic hepatitis C patients infected by genotype 1 are the least responsive to combination therapy and therefore monitoring response is important in identifying non-responders quickly, permitting therapy discontinuation and avoiding side effects and costs. We examined the usefulness of measuring total HCV Core Ag in early treatment with peginterferon alpha-2b and ribavirin in genotype 1 patients in the prediction of response and compared the results with those from HCV RNA quantification. METHODS: Two hundred and sixty-eight serum samples from 46 genotype 1 patients receiving combination therapy were examined for HCV Core Ag and quantitative HCV RNA. RESULTS: At baseline, mean HCV RNA and HCV Core Ag concentrations were significantly lower in sustained virologic responders than in non-responders. The negative predictive value of HCV Core Ag testing in predicting non-response at week 12 is 100%, and for a 2 log drop in HCV RNA, using two quantitative tests, it is 88%. CONCLUSIONS: HCV Core Ag determination allows the identification of non-responders with only one test at week 12 and permits stopping therapy in these patients. HCV Core Antigen testing is cheaper and easier to perform than HCV RNA quantification.  相似文献   
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