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1.
Stored sera from 181 Greek patients with hepatocellular carcinoma (HCC), 35 patients with metastatic liver cancer, and 416 hospital controls with diagnoses other than malignant neoplasm or liver disease were examined with first and second generation hepatitis C virus (HCV) enzyme immunoassays as well as with five HCV supplemental assays based on structural and nonstructural HCV peptides. Second generation HCV enzyme immunoassays were more sensitive than first generation assays. However, both assays had suboptimal specificity using the standard reactivity criterion (absorbance of sample to cutoff greater than or equal to 1.0). Specificity was improved by centrifugation and by using a sample's optical density to cutoff ratio greater than or equal to 3.0 or supplemental assays; in this instance the prevalence of antibodies to HCV was 13.3% (24 of 181), 0 (0 of 35), and 1.4% (6 of 416) in HCC, metastatic liver cancer, and hospital controls, respectively. A similar estimation of prevalence of antibody to HCV in HCC (12.5% or 4 of 32) was obtained when the recombinant immunoblot assay, second generation, was used to screen a random sample of HCC patients. The relative risk linking HCV to HCC was estimated as 10.4 (95% confidence interval, 4.2-26.0; P less than 0.0001). These data suggest that the prevalence of antibodies to HCV in HCC using stored sera has been previously overestimated even though the evidence of a causal association of HCV with HCC persists.  相似文献   
2.
Neuropsychological findings from investigation of 46 HIV-seropositive asymptomatic and 14 HIV-seropositive symptomatic haemophiliacs without AIDS-related complex (ARC) or AIDS, with known duration of HIV seropositivity were compared with 29 seronegative controls. Subjects were assessed blindly using a battery of sensitive computerized neuropsychological tests. They underwent a thorough neurological examination, were assessed for mood and screened for psychopathology. Symptomatic HIV-positive haemophiliacs without ARC or AIDS showed statistically significant decreased performances compared with HIV-negatives in choice reaction, visuomotor coordination and global attentional performance (P = 0.018, 0.039 and 0.044, respectively). HIV-positive asymptomatic subjects gave lower performances than HIV-negative subjects in all tests, although these differences were not statistically significant. However, there was a statistically significant trend for these findings between seronegative, asymptomatic and symptomatic groups. Impairment was not associated with mood factors. Duration of seropositivity was found to be a more important factor than Centers for Disease Control stage in the choice reaction test (P less than 0.01). These findings indicate that mild cognitive impairment observed during the natural history of HIV infection in haemophiliacs without ARC or AIDS may be a progressive phenomenon not necessarily associated with the clinical expression of HIV infection.  相似文献   
3.
The prevalence of hepatitis C virus (HCV) infection in 182 prospectively followed adult patients (110 males, 72 females) with acute non-A, non-B hepatitis and its correlation with progression to chronic hepatitis were studied. These patients were followed for a mean of 24.7 +/- 13.1 (range, 6-57) months. By using a specific enzyme immunoassay for the detection of antibodies against C100-3 polypeptide of HCV, 96 (52.7%) were found antibody positive. HCV was implicated in 64/89 (71.9%) of the cases with classical parenteral exposure but only in 18/64 (28.1%) of the community-acquired cases. Progression to chronic hepatitis was observed more frequently in antibody-positive than in antibody-negative cases (60/96 or 62.5% vs. 27/86 or 31.4%, P = 0.00002). Progression was also observed more often in males than in females (66/112 or 58.9% vs. 21/70 or 30.0% P = 0.0001), both in the antibody positive (48/68 or 70.6% vs. 12/28 or 42.9%, P = 0.01) and in the antibody negative (18/44 or 40.9% vs. 9/42 or 21.4%, P = 0.043) cases. These data indicate that (a) acute hepatitis due to HCV is characterized by a high rate of chronicity, especially in males, and (b) a non-A, non-B, non-C agent or a different strain of HCV may be responsible for the majority of the community-acquired cases of non-A, non-B hepatitis in Greece.  相似文献   
4.
Prevalence and genotypic distribution of TT virus in Athens, Greece   总被引:1,自引:0,他引:1  
The prevalence of TT virus (TTV) infection in various population groups from Athens, Greece, was assessed by the polymerase chain reaction (PCR) using two primer sets from distinct regions of the genome: the conventional set derived from the open reading frame-1 (ORF-1) and the new, highly sensitive set targeting the region that includes the TATA signal localized upstream of ORF-2. Based on both primer sets, TTV DNA was detected in 42/50 (84.0%) healthy individuals, 42/50 (84.0%) chronic hepatitis C patients, 31/39 (79.5%) acute non-A-E hepatitis patients (group I), 14/16 (87.5%) renal failure patients with acute non-A-E hepatitis (group II), 47/50 (94.0%) intravenous drug users (IVDU), 36/50 (72.0%) hemophiliacs, and 21/31 (67.7%) hemodialysis patients. The presence of TTV was not associated with any particular risk group, and no differences were observed in relation to demographic, biochemical and virological characteristics between TTV DNA-positive and -negative patients. TTV did not seem to have a profound effect on the course of chronic C or acute non-A-E hepatitis either. Phylogenetic analysis revealed that TTV strains circulating in the greater metropolitan area of Athens belong not only to the G1 and G2 genotypes that are encountered worldwide, but also to G3 and to G5 that are found mainly in Europe and Asia, respectively. Further studies will shed light on the role of this highly prevalent virus.  相似文献   
5.
The aim of this study was to determine the frequency of hepatitis E virus (HEV) infection in a population of Greek adults with community-acquired (sporadic) non-A, non-B hepatitis found to be seronegative for antibodies to hepatitis C virus (anti-HCV). All patients admitted to the Liver Unit of Western Attica General Hospital and diagnosed as having acute community-acquired non-A, non-B hepatitis between February, 1986, and May, 1990, were enrolled in follow up studies (n = 66). Nineteen patients with HCV infection and 11 patients with acute non-A, non-B, non-C hepatitis that progressed to chronicity were excluded. Convalescent sera were tested for antibody to HEV (anti-HEV) by a fluorescent antibody blocking assay in 33 of 36 eligible patients. One of the 33 (3%) patients was found to be positive for anti-HEV. Anti-HEV testing of all 20 available serum specimens from this patient showed evidence of anti-HEV seroconversion at the fourth week after the onset of hepatitis. The patient had not travelled abroad or within Greece or had not had apparent contact with people from foreign countries for the previous 3 months. These data show that HEV infection is not a major cause of community-acquired non-A, non-B hepatitis in Greece. However, the reported case of HEV hepatitis suggests that HEV may retain a low endemicity in Greece. More extensive seroprevalence studies are needed for an accurate estimation of the extent of HEV infection in the southeastern European countries. © 1994 Wiiey-Liss, Inc.  相似文献   
6.
Air pollution and cause specific mortality in Athens.   总被引:6,自引:1,他引:5  
STUDY OBJECTIVE--The aim was to investigate the reported association between air pollution and cause specific mortality in the city of Athens. DESIGN--Cause specific mortality was contrasted between 199 d with high values of air pollution and 2*199 comparison days with low pollution, matched in a 1:2 ratio on the basis of various confounding factors. Statistical analysis was done, taking matching into account, using analysis of variance for randomised blocks. SETTING--The study was confined to the city of Athens, using data obtained between 1975 and 1982. PARTICIPANTS--Cause of death was assessed in all 25 138 persons dying in the 3*199 d studied. MEASUREMENTS AND MAIN RESULTS--Causes of death were evaluated blindly by two medically qualified investigators on the basis of information in the death certificates. Mortality was generally higher during the high pollution days but the difference was more pronounced and more significant for respiratory conditions, even though the number of deaths in this category was smaller than the corresponding numbers in the other two categories examined (cardiac and "other" deaths). CONCLUSION--The results show that the short term association between air pollution and overall mortality in Athens is likely to be causal, since it is particularly evident with respect to respiratory conditions, for which a biological air pollution link is more plausible.  相似文献   
7.
We have validated ECG-gated emission tomography using technetium-99m methoxyisobutylisonitrile for the assessment of regional ventricular function by comparing it with cine magnetic resonance imaging (MRI). Gated tomography was performed at rest in 24 patients referred for myocardial perfusion imaging [17 males and seven females with a mean age of 58 years, nine of whom had had a previous myocardial infarction (MI)]. Scores were assigned to each of nine myocardial segments for wall motion and for thickening. Cine MRI was analysed in an identical fashion. Four out of 216 (2%) segments were uninterpretable by gated tomography because of inadequate tracer uptake. In eight patients without coronary artery disease (CAD), wall motion and thickening were normal by both methods. Gated tomography showed abnormal wall motion or thickening in all patients with previous MI and in five of seven patients with CAD but no prior MI. Association between wall motion and thickening was good (r s=0.86). Overall, there was good agreement between gated tomography and MRI for both wall motion (178/212 segments, =0.66) and wall thickening (184/212 segments, =0.69). In segments with severely reduced perfusion, however, there was poorer agreement (=0.31). Interobserver and intraobserver agreement was high ( from 0.61 to 0.78). Thus, in patients investigated for CAD, there is good overall agreement between gated tomography and MRI but the agreement is lower in segments with severe perfusion defects.  相似文献   
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