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1.
In clinical and pathological terms hepatitis C virus (HCV)-infected patients can be subdivided into two main groups with and without mixed cryoglobulinaemia (MC). Involvement of blood mononuclear cells by HCV has potentially important implications. To this end, HCV-RNA levels in peripheral blood lymphocytes (PBL) preparations of 20 chronically HCV-infected patients with MC were measured and compared with those found in a group of 20 patients without MC matched for age, serum HCV-RNA, infectious genotype, source and presumable duration of infection. Phenotypic abnormalities of PBL subsets in each group of patients were determined by cell surface marker expression and compared. Results showed a significant enrichment of HCV-RNA in PBL of MC patients compared with a non-MC group (P = 0.01). Different distribution of HCV-RNA was accompanied by evidence of an increased frequency of circulating B cells. These data indicate that MC patients are characterized distinctly by a higher quota of cell-associated viral load.  相似文献   

2.
The detection of traces of semen in cervicovaginal secretions (CVS) from sexually active women practicing unprotected sex is a prerequisite for the accurate study of cervicovaginal immunity. Two semen markers, the prostatic-specific antigen (PSA) and the Y chromosome, were detected in parallel in CVS obtained by a standardized vaginal washing of consecutive women attending the principal medical center for sexually transmitted diseases of Bangui, Central African Republic. PSA was detected by immunoenzymatic capture assay in the cell-free fraction of CVS, and the Y chromosome was detected by a single PCR assay of DNA extracted by silica from the cell fraction (Y PCR). Fifty (19%) cell-free fractions of the 264 beta-globin-positive CVS samples were positive for PSA, and 100 (38%) cell fractions of the CVS samples were positive for the Y chromosome. All the 50 (19%) PSA-containing CVS samples were also positive for the Y chromosome. Fifty (19%) CVS samples were positive only for the Y chromosome, with no detectable PSA. The remaining 164 (62%) CVS samples were both PSA and Y chromosome negative. These findings demonstrate that CVS from sexually active women may contain cell-associated semen residues unrecognized by conventional immunoenzymatic assays used to detect semen components. The detection of cell-associated male DNA with a highly sensitive and specific procedure such as Y PCR constitutes a method of choice to detect semen traces in female genital secretions.  相似文献   

3.
Serum samples from 46 children with chronic and probably transfusion acquired hepatitis were tested for the presence of hepatitis C virus (HCV) RNA by a “nested” polymerase chain reaction (PCR) assay, to judge a possible risk of HCV transmission from these patients. In 73% of the samples, viral RNA was detected, indicating a high virus prevalence in this patient group. High titers of HCV-RNA were observed in some sera as shown by the detection of virus in some samples even at dilutions of 10?3. Comparison of simultaneously obtained PCR results and ALT values revealed no significant correlation between virus presence in serum and higher ALT levels. It was, however, shown that unusually high ALT values may reflect a high titer of viral RNA in serum. To investigate the prevalence of viral RNA in saliva, which could be a vehicle of virus transmission, 35 throat washing samples from the HCV-infected children were screened by PCR. Using three different sample preparation procedures, 20% of the throat washings were found to be positive for HCV-RNA. This indicates a prevalence of virus in this fluid lower than that reported previously. © 1994 Wiley-Liss, Inc.  相似文献   

4.
The detection of traces of semen in cervicovaginal secretions (CVS) from sexually active women practicing unprotected sex is a prerequisite for the accurate study of cervicovaginal immunity. Two semen markers, the prostatic-specific antigen (PSA) and the Y chromosome, were detected in parallel in CVS obtained by a standardized vaginal washing of consecutive women attending the principal medical center for sexually transmitted diseases of Bangui, Central African Republic. PSA was detected by immunoenzymatic capture assay in the cell-free fraction of CVS, and the Y chromosome was detected by a single PCR assay of DNA extracted by silica from the cell fraction (Y PCR). Fifty (19%) cell-free fractions of the 264 β-globin-positive CVS samples were positive for PSA, and 100 (38%) cell fractions of the CVS samples were positive for the Y chromosome. All the 50 (19%) PSA-containing CVS samples were also positive for the Y chromosome. Fifty (19%) CVS samples were positive only for the Y chromosome, with no detectable PSA. The remaining 164 (62%) CVS samples were both PSA and Y chromosome negative. These findings demonstrate that CVS from sexually active women may contain cell-associated semen residues unrecognized by conventional immunoenzymatic assays used to detect semen components. The detection of cell-associated male DNA with a highly sensitive and specific procedure such as Y PCR constitutes a method of choice to detect semen traces in female genital secretions.  相似文献   

5.
BackgroundThe role of sexual activity in hepatitis C virus (HCV) transmission remains controversial. Studies to date have not explored the relationship between HCV shedding in cervicovaginal fluids and the presence of menstrual or other blood.ObjectivesSince cross-sectional studies may underestimate the prevalence of viral shedding, we performed a 56-day longitudinal study of cervical HCV shedding.Study designWomen self-collected cervicovaginal swabs for 56 consecutive days, while keeping a diary of menses and genital symptoms. Swabs were tested for HCV RNA and cellular DNA by quantitative PCR, and hemoglobin by spectrophotometry.ResultsSixteen women contributed a total of 701 cervicovaginal swabs (mean collection period 48 days, range 18–56). Detection of HCV RNA was associated with detection of hemoglobin. Premenopausal women were more likely than post-menopausal women to have HCV RNA detected in cervicovaginal fluids. For premenopausal women, detection of HCV RNA was more likely during menstruation (OR = 56.4) or when hemoglobin was detected in cervicovaginal fluids, even if menstruation was not occurring (OR = 35.4). No woman post-hysterectomy had HCV RNA detected in cervicovaginal fluids on any day, regardless of whether hemoglobin was detected.ConclusionsOur findings are consistent with a low likelihood of sexual transmission of HCV. The results suggest that shedding of HCV RNA in the female genital tract is associated with the presence of blood, and requires the presence of a cervix. Clinicians should consider advising premenopausal women who are concerned about transmitting infection that infectivity may increase during menstruation.  相似文献   

6.
Occult hepatitis B virus (HBV) and occult hepatitis C virus (HCV) infection are two recently described different forms of HBV and HCV infections. This work compares the clinical, virologic, and histologic characteristics of patients with occult dual infection to those of patients with single occult HBV or HCV infection. Seventy-six patients with abnormal liver function tests of unknown etiology (serum HBsAg, anti-HCV, HBV-DNA, and HCV-RNA negative) were included in the study. Viral genomes were tested in liver by real-time PCR and confirmed by in situ hybridization. Of the 76 patients, 17 had occult HBV infection (intrahepatic HBV-DNA positive, HCV-RNA negative), 35 had occult HCV infection (intrahepatic HCV-RNA positive, HBV-DNA negative) and 24 occult dual infection (intrahepatic HCV-RNA and HBV-DNA). No differences among the three groups were found regarding clinical and epidemiologic data. The median load of intrahepatic genomic and antigenomic HCV-RNA strands was similar between single occult HCV infection and occult HBV and HCV dual infection. The percentage of HCV-infected hepatocytes did not differ between these groups. In occult single HBV infection, intrahepatic levels of HBV-DNA and percentage of HBV-infected hepatocytes were similar to the group of patients with occult dual infection. Finally, no differences were found in histological liver damage among the three groups. In conclusion, liver disease in patients with occult dual infection was not more severe than in patients with single occult HBV or occult HCV infection. Moreover, in occult dual infection there is no a reciprocal inhibition of the viral genomes.  相似文献   

7.
A semiautomated dot blot assay and cDNA polymerase chain reaction (PCR) were used to study longitudinal anti-hepatitis C virus (HCV) recognition patterns in relation to presence of HCV-RNA in transfusion recipients and their infectious donors. In 9 recipients, 4 different patterns of HCV infection were observed: (A) persistent HCV carriage accompanied by chronic hepatitis in 6, (B) acute resolved hepatitis, but persistent HCV replication in one, and (C) continuous HCV replication without hepatitis in one and (D) acute resolved hepatitis with clearance of infection in one. This last self-limited infection was characterized by the disappearance of HCV-RNA as well as anti-HCV reactivity. In contrast, antibody reactivity persisted in 7 of 8 patients with chronic HCV infection who could be followed until 1990. Seven of the 9 recipients developed antibodies to all recombinant peptides in dot blot assay; one became positive for anti-C33 and anti-core and one developed anti-core only. The sequence of appearance of antibodies differed among individual patients. In 7 patients with full anti-HCV recognition patterns, the sequence of events was (mean and limits in days after transfusion): onset of hepatitis at day 50 (22-74), seroconversion of anti-C33 at day 91 (59-129), anti-core at day 133 (54-203), and anti-C100 at day 143 (59-365). The incorporation of C33 and core proteins, in addition to C100, in the second generation anti-HCV ELISA enhanced the detection rate in the HCV-infected transfusion recipients from 7/9 (78%) to 9/9 (100%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

8.
OBJECTIVES: To detect HIV-1 in cellular and acellular fractions of cervicovaginal secretions obtained by cervicovaginal lavage (CVL) and evaluate viral genotypes in the HIV-1-positive CVL samples. STUDY DESIGN/METHODS: This study consists of 37 HIV-1-seropositive pregnant and nonpregnant women from the United States. A total of 63 paired CVL and blood samples were collected. HIV-1 DNA from cervical cells (CC) and virion RNA from cervical supernatant (CS) was detected by gag polymerase chain reaction (PCR) assays. The HIV-1 genotypes were determined by analyzing the nested PCR-amplified V3 region sequences of the HIV-1 gp120 envelope gene. RESULTS: Within this cohort, 95% of the women were on single or combination antiretroviral therapy. Of the pregnant women, 63% of samples had HIV-1 viral DNA in the CC, and 29% of samples were positive for viral RNA in the CS. Among nonpregnant women, 71% of samples were positive for HIV-1 DNA in CC, and 46% of samples tested positive for virion RNA in CS. Plasma viral load ranged between 10,000 and 100,000 copies/mL and showed significant correlation with the detection of HIV-1 RNA in the CVL; this relation was less apparent with viral DNA in CC. The viral blood and CVL specimens were further analyzed by evaluating the genotypes of HIV-1 variants. In most patients, a high degree of similarity was observed between the viral sequences derived from blood and CVL samples. Two patients demonstrated closely related but somewhat distinct genotypic variants in CVL and blood. One subject showed clear compartmentalization in which distinct viral genotypes were observed in CVL and blood. Based on V3 loop analyses of gp120, with one exception, the cervicovaginal secretions harbored viral populations with a macrophage (CCR5)-tropic phenotype. CONCLUSIONS: This study demonstrates the unique characteris tics of HIV-1 strains in the genital secretions of a relatively large cohort of HIV-1-infected women in the United States. These results are important for further analysis of HIV-1 transmission and pathogenesis in vivo and for rational vaccine design.  相似文献   

9.
Immune responses against hepatitis C virus (HCV) have been studied by numerous groups. However, details concerning the production of antibodies to antigenically variable epitopes remain to be elucidated. Since the sequences of the variable regions of several HCV proteins are different among the virus strains infecting patients, we decided to design peptide combinations that represent the theoretical maximum antigenic variation of each epitope to be used as capture antigens. We prepared six peptide mixtures (hypervariable epitope constructs; HECs) representing six different epitopes from structural and non-structural proteins of HCV from genotypes 1-6. Plasma from 300 HCV patients was tested to determine if their antibodies recognize the synthetic constructs. All the patients were chronically infected with diverse HCV genotypes and did not receive antiviral treatment. Antibodies to one or more of the HECs were detected in all of the HCV-infected individuals. Immunogenicity of the HCV HECs was also evaluated in outbred and inbred mice. Strong HEC-specific antibodies were produced, and cellular responses were also induced that were Th-1 rather than Th-2. Our results show that HCV HECs are both antigens that can be used to detect the broad cross-reactivity of antibodies from HCV-infected patients, and strong immunogens that can induce antigen-specific humoral and cellular immune responses in mice.  相似文献   

10.
Reported here are details of a simultaneous outbreak of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections that occurred in a hemodialysis centre in northern Italy, with three patients seroconverting for HBsAg and four patients seroconverting for HCV antibodies. Phylogenetic analysis of the E2 region of the isolates from HCV-seroconverted patients showed the sequences were grouped in the same distinct branch as in a chronically HCV-infected patient, suggesting that the chronically infected patient was the index case. For the patients with HBV infection, phylogenetic analysis showed strong clustering among the sequences of the three patients who seroconverted to HBsAg and no relatedness between them and the sequences of patients chronically infected with HBV. For one of the patients who seroconverted to HBsAg, the last test with negative results for HBV markers had been performed 18 months prior to HBsAg seroconversion. This patient may have been previously infected with HBV and is presumed to be the source of the outbreak. This report emphasizes the importance of using universal precaution measures and HBV vaccination to prevent the transmission of viral hepatitis among chronic hemodialysis patients.  相似文献   

11.
12.
Enteroviruses (EVs) (Picornaviridae) in the female genital tract may constitute possible sources of antenatal or perinatal infection. The presence of EV genomes in the acellular part of cervicovaginal lavages of 119 non-pregnant childbearing-aged African women was determined using a semiquantitative RT-PCR and hybridization detection assay. EV-specific cervicovaginal IgA and IgG antibodies were also detected by immunocapture ELISA assays. Of 119 CVS samples tested, only 10 (8%) were positive for the detection of EV RNA, demonstrating an genital shedding of EVs in African woman. EV-RNA positivity was not associated with the HIV serostatus or with the presence of semen traces in female genital secretion. The microwell hybridization assay of EV amplified RT-PCR products indicated the presence of low levels of EV genomes, ranging from 50 to 100 RNA copies per ml of genital fluids. EV-specific cervicovaginal IgA or IgG antibodies were detected only in two hemoglobin-positive cervicovaginal secretions samples from women without genital EVs. The lack of EV specific IgA or IgG antibody secretion by the cervicovaginal mucosa supported the hypothesis of genital shedding of EVs without ongoing viral replication in the female genital tract. In conclusion, the findings demonstrated the presence of EV genomes in nearly 10% of childbearing-aged women living in Central Africa, and provided the basis of possible antenatal or perinatal transmission of EV from mother-to-child.  相似文献   

13.
14.
Based on recent LightCycler techniques developed for the quantitation of serum HCV RNA, we have developed a quantitative method for the intracellular hepatitis C virus (HCV) RNA using LightCycler PCR. A simple real-time PCR assay, based on the SYBR Green I dye and LightCycler fluorimeter and with no probe requirement, is described. In the presence of 0.5 microg of cellular RNA, it was demonstrated that as few as 25 copies of HCV RNA could be specifically detected with a set of primers that amplify a 144-base pair sequence unique to the 5'-noncoding region of HCV RNA. We demonstrated that this method was useful for the evaluation of antiviral reagents using HCV-infected human cultured cells.  相似文献   

15.
16.
Purpose: Identification of hepatitis C virus (HCV) genotypes is very important in the selection of antiviral treatment, dose adjustment of antiviral agents, determining the treatment duration and following-up of treatment response. We aimed to determine the distribution pattern of HCV genotypes in chronic hepatitis C infection (CHC) patients. Materials and Methods: We have included 106 CHC patients who were positive in the anti-HCV and HCV-RNA tests performed in our hospital during the 16-month period. Anti-HCV assays were performed on device using a chemiluminescent microparticle immunoassay, while HCV-RNA tests and HCV genotyping assays were performed by real-time polymerase chain reaction. Results: Of the 106 cases; genotype 1b was detected in 67.0%, genotype 3 was detected in 16.0%, genotype 1a was detected in 14.2% and genotype 2 was detected in 2.8% patients. Genotypes 4, 5 and 6 were not detected in our study group. There were no statistically significant differences between the gender and age groups according to the HCV genotype distribution. The genotype 3 detection rate (16%) was the highest rate among the studies compared with the other studies in our country. Conclusions: Events that cause social changes such as war and immigration and intense commercial and touristic activities affect and alter the HCV genotype distribution in HCV-infected patients. For this reason, further multicentre studies are required reflecting all the regions in order to determine the genotype distribution in HCV-infected patients at regular intervals.  相似文献   

17.
Cryptic hepatitis C virus (HCV) infection relates to patients infected chronically with HCV that are seronegative but have HCV-RNA. These patients are not identified by the standard serological tests for HCV, which are based on detection of antibodies to core, NS3 and NS5 antigens. They will, therefore, be wrongly diagnosed as non-infected, and are considered as a potential risk for others. Cryptic HCV infection in dialysis units occurs frequently and, due to medical procedures, is a major factor for contracting the virus when unrecognised. This study was conducted in order to assess the humoral immune responses to E2-antigen in sera of patients infected chronically with HCV. Recombinant E2 protein in enzyme linked immunosorbent assay (ELISA) and Western blot (WB) were used to test the occurrence of anti-E2 antibodies in the sera of patients from the liver clinic and of dialysis patients. The presence of E2 antibodies was found to be correlated with the presence of HCV-RNA and with viral load. Antibodies to the E2 protein could be detected in as many as 30% of the sera from dialysis patients with cryptic HCV infection (HCV-RNA only). The results suggest that detection of anti-E2 antibodies may enhance significantly HCV serological standard testing; especially among patients on dialysis, and that antibodies to envelope E2 protein appear to depend on and correlate with the presence of HCV particles.  相似文献   

18.
19.
The mean prevalence of anti-hepatitis C virus (HCV) in Italy is 0.87%. It reaches 2% in Campania, Southern Italy. Approximately 50% of community acquired non-A, non-B (NANB) hepatitis cannot be associated with known parenteral exposure. A recent Italian study has shown that the only demonstrable risk factor in 9% of acute C/NANB hepatitis is dental treatment. There are no data on direct contamination by HCV of dental surgeries. Possible environmental contamination by HCV-RNA was investigated in dental surgeries after treatment of anti-HCV and HCV-RNA positive patients. Thirty-five anti-HCV and HCV-RNA positive patients with chronic hepatitis underwent dental treatment and were enrolled in this study. Eight had chronic persistent hepatitis (CPH), 23 chronic active hepatitis (CAH), and 4 cirrhosis. A total of 328 samples collected from instruments and surfaces were tested after dental treatment of 35 anti-HCV positive patients. The presence of HCV-RNA was determined by polymerase chain reaction (PCR) to evaluate contamination of instruments and surfaces in dental surgeries. Twenty (6.1%) out of 328 collected samples were positive for HCV-RNA. The positive samples were from work benches (two), air turbine handpieces (one), holders (four), suction units (one), forceps (four), dental mirrors (two), and burs (six) Our data indicate that there is extensive contamination by HCV of dental surgeries after treatment of anti-HCV patients and that if sterilisation and disinfection are inadequate there is the possible risk of transmission to susceptible individuals. © 1995 Wiley-Liss, Inc.  相似文献   

20.
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