摘要:

AbstractThere are 2 subtypes of human T‐cell lymphoma/ leukemia virus type II (HTLV‐II), A and B. HTLV‐II is increasingly associated with rare forms of lymphocytic neoplasia and a neurodegenerative disorder, characterized by hyperspasticity and ataxia. We have used PCR to amplify, clone and sequence 140 bp of thepolgene from many isolates of HTLV‐IIA and HTLV‐IIB from around the world. Analysis of these and other published sequences established that all HTLV‐IIA sequences contained a unique Hinf I site and all HTLV‐IIB sequences a unique Mse I site. A rapid and specific oligomer restriction (OR) assay was developed utilizing the primer pair SK110/SK111 and subsequent digestion with these enzymes. Concordance between sequenced and OR‐based subtyping of DNA amplified by PCR was absolute among 22 HTLV‐II isolates tested.Further OR or sequence analyses on an additional 30 other isolates indicated that the majority of North American non‐indian HTLV‐II isolates were subtype A, while all Paleo‐Amerindian samples, including those from the Seminole of Florida; the Guaymi from Panama; and the Toba, Chorote, Wichi, and Chulupe of Argentina, belonged to subtype B. The SK110/SK111 PCR‐OR format should facilitate molecular epidemiology studies of HTLV‐II infection and allow for subtype stratification in assessing the sensitivity and specificity of HTLV detection formats and HTLV‐II disease associ

ISSN:0146-6615    

DOI:10.1002/jmv.1890450102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractA simple and cheap assay suitable for screening for anti‐HIV 1 and anti‐HIV 2 and discriminating between them was evaluated. In it specimens are incubated in U‐bottomed microplate wells coated with anti‐human IgG for 30 min at room temperature. After washing, 100 μl of a 1 in 50 dilution of HIV 1‐coated gelatin particles (Serodia‐HIV 1/2, Fujirebio) are added. Settling patterns are read on the second day: A positive reaction is indicated by adherence of the particles and a negative by a button. The HIV 1 particles are then washed away and HIV 2 particles added. Anti‐HIV 2 reaction patterns are read on the third day. To assess the performance of the modified “GACPAT HIV 1+2” assay a panel of 1,621 serum/plasma specimens was used. It comprised validated anti‐HIV 1 positive (n = 220), anti‐HIV 2 positive (n = 214), dual anti‐HIV 1/anti‐HIV 2 positive (n = 11), and anti‐HIV negative (n = 1,176) serum/plasma specimens.All 434 specimens that contained anti‐HIV 1 or anti‐HIV 2 reacted positively with the homologous particles. The 11 dually positive specimens reacted positively with both HIV 1 and HIV 2 particles. Five (2.3%) anti‐HIV 1 and five (2.3%) anti‐HIV 2 positive specimens gave positive reactions with both particle types, but none of the five cross‐reactive anti‐HIV 2 specimens were dually reactive when the order of particle addition was reversed. One repeat false positive reaction was recorded with the HIV 1 particles and none with the HIV 2 particles, giving specificities of 99.9% and 100%, respectively. Type specificity was 98.8% after the results of the reverse assay had been taken into account. The assay was sensitive for anti‐HIV 1 in seroconversion series and for anti‐HIV 2 in highly diluted specimens.GACPAT HIV 1 +2 is an accurate anti‐HIV assay applicable to serum/plasma. With few exceptions anti‐HIV 1 positive specimens are reactive only on the second day and anti‐HIV 2 positive specimens only on the third day. It thus discriminates anti‐HIV 2 from anti‐HIV 1, probably through depletion of cross‐reacting antibodies by the reaction wi

ISSN:0146-6615    

DOI:10.1002/jmv.1890450103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractAlthough natural mumps virus infection is believed to induce lifelong immunity, our laboratory was confronted with 82 patients who developed mumps‐evoking lesions but exhibited serological evidence of a booster immune response, namely a rise or a high titer of virus‐specific IgG, without IgM. In order to provide arguments favoring the existence of recurrent mumps attacks, the age, symptomatology, and humoral response of these patients (group 1) were compared to that of 82 randomly selected true primary infected patients (group 2), 10 parainfluenza virus‐infected patients (group 3), and 20 noninfected mumps‐immune subjects (group 4), Enzyme‐linked immunosorbent assay (ELISA) procedures with different viral antigenic preparations were used for determination of specific IgM, IgA, IgG, IgG subclasses, and IgG avidity. The patients of group 1, older than those of group 2 (28 vs. 10 years,P<0.0001), presented a significantly less severe and less typical symptomatology. Against the whole virus they exhibited IgG of higher avidity (P<0.001), a lower prevalence and titer of IgA (10 vs. 68%,P<0.0001 and 278 vs. 5,009,P<0.001, respectively). Values obtained for IgG 1, 2, and 3 were significantly different between the two groups. Prevalence and absorbance of nucleocapsid‐directed IgG 3 were significantly lower in group 1 (27 vs. 46%,P<0.01 and 0.444 vs. 0.869,P<0.01, respectively). A significant discrepancy also allowed patients from group 1 to be distinguished from those of groups 3 and 4. So the presumed mumps‐reinfected patients were different from primary infected ones and presented features reminiscent of a secondary immune response, suggesting the not uncommon occurrence of symptomatic reinfections by the mumps virus. This concept is of importance in medical practice. © 1995 W

ISSN:0146-6615    

DOI:10.1002/jmv.1890450104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractHepatitis C virus (HCV) infection frequently causes chronic hepatitis and lack of virus clearance in these patients. In addition, many patients infected by HCV also present with hypergamma‐globulinemia in the early stage of chronic infection. These observations raise a possible viral superantigen effect induced by HCV, because viral superantigen found in human immunodeficiency virus (HIV) or in replication of defective murine leukemia virus (MuLV) is associated with T‐cell dysfunction and polyclonal activation of B cells. The possibility was investigated of whether HCV encodes any superantigen by analyzing the usage of T‐cell receptor (TCR) from the peripheral blood lymphocytes (PEL) of patients with chronic hepatitis C. Two groups, one with hyper‐gammaglobulinemia and the other without hy‐pergammaglobulinemia, were studied for the usage of TCR β chain by reverse transcription‐polymerase chain reaction (RT‐PCR) analysis. It was found that all genes of Vβ variable chain were used in the PBL of these patients. Furthermore, there was no significant difference of the TCR expression pattern between these two groups, nor a complete deletion of a particular T‐cell subset in either group. These results do not provide evidence for HCV superantigen, but indicate that the TCR usage in the patients was neither defective nor biased. © 19

ISSN:0146-6615    

DOI:10.1002/jmv.1890450105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractResponse to ribavirin therapy (1,000‐1,200 mg/day for 6 months) was evaluated in nine patients with chronic hepatitis C virus (HCV) infections who had previously failed to respond to a 6‐month course of alpha‐interferon. All had chronic active hepatitis with elevated serum aminotransferase activities (mean ± SD = 138 ± 66IU/I). During ribavirin therapy, three showed a complete response (normalized serum ami‐notransferase), although in one patient this returned to the pretreatment level 2 months after treatment was stopped. Three others showed a partial response (serum aminotransferase reduction by ⩾50;%) and the remainder showed no response. There were no consistent changes in HCV‐RNA (positive strand) in serum, liver, or peripheral blood mononuclear cells during therapy, but two patients lost HCV‐RNA from serum and three of five patients with negative strand HCV‐RNA in their livers lost this putative replicative form of the virus. The findings suggest that ribavirin may exert its effects by suppressing viral replication rather than by eradicating the virus, at least in this group of patients, and that the drug may have some benefit in selected cases of chronic hepatitis C that are resistant to inter‐feron. However, peripheral blood mononuclear cells represent a major extrahepatic reservoir of HCV and the present regimen of ribavirin therapy did not significantly affect this situation. More prolonged therapy may be required to eradicate the virus from this large pool of cells with the potential to continually reinfect the liver. ©

ISSN:0146-6615    

DOI:10.1002/jmv.1890450106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThis paper documents clinically significant recurrence of hepatitis A virus (HAV) infection in a 63‐year‐old man transplanted for HAV‐related acute liver failure. HAV RNA was documented in the explant and, following early clearance from the blood and graft, was again detected in postoperative biopsies at the time of an acute hepatic illness. Although the clinical and biochemical abnormalities resolved completely, the patient had a second episode of graft dysfunction 6 months later and investigations revealed hepatitis C virus (HCV)‐related chronic active hepatitis consistent with acquired HCV infection at the time of transplantation. The possible interaction with hepatitis A may have delayed the appearance of hepatitis C. Administration of HAV immunoglobulin at the time of transplantation should be considered in all cases of HAV‐related fulminant hepatic failure. © 1995 Wiley

ISSN:0146-6615    

DOI:10.1002/jmv.1890450107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe 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 individual

ISSN:0146-6615    

DOI:10.1002/jmv.1890450108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractThe effect of interferon—γ (IFN‐γ) on dengue virus multiplication in human peripheral blood mono‐cytes was investigated. Enriched monocytes were treated with IFN‐γ and then infected with dengue virus type 2 either directly or in the presence of optimal infection‐enhancing levels of antibodies. Pretreatment of monocytes from dengue‐immune donors with 100 IU/ml of IFN‐γ caused 12‐ to 97‐fold and 13‐ to 137‐fold reduction of virus yields at 24 hr after infection in the absence and presence of an anti‐flavivirus monoclonal antibody, respectively. IFN‐γ also diminished virus yields when infection of monocytes from a donor who lacked anti‐dengue antibody was enhanced 40‐fold. The percentage of infected monocytes in IFN‐γ‐pretreated cultures was similarly reduced. Dominance of the antiviral effect of IFN‐γ in monocytes is in contrast to an augmenting effect previously observed in the promonocy

ISSN:0146-6615    

DOI:10.1002/jmv.1890450109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractA panel of 16 type‐specific synthetic peptides corresponding to variable antigenic regions within the hepatitis C virus (HCV) core, nonstruc‐tural 4 (NS4), and NS5 proteins was synthesised. The peptide panel was used to develop an enzyme immunoassay (EIA) for the detection of antibodies directed to HCV type 1 (genotypes I/1a and II/1 b), type 2 (genotypes III/2a and IV/2b), and type 3 (genotype V/3). The peptides corresponded to residues 68–81 of the HCV core (types 1,2, and 3), residues 1692–1705 and 1710–1728 of HCV NS4 (types 1 a, 1 b, 2a, 2b, and 3), and residues 2303–2319 of HCV NS5 (types 1a, 1b, 2a, and 2b). The 16‐peptide panel was evaluated using human sera from 46 carriers of HCV, which were genotyped in parallel by the polymerase chain reaction (PCR) using primers specific for types I, II, III, IV, and V of HCV core. Of the 46 carriers, 14 (30%) were infected by HCV genotype I, 7 (15%) by genotype II, 16 (35%) by HCV genotype IV, and 6 (13%) by HCV of genotype V. Two carriers had double infections of types I and II, and the HCV strain of one carrier could not be genotyped. Using the serotyping system, 40 (89%) out of the 45 genotyped carriers were found to contain type‐specific antibodies corresponding to the genotypes identified by PCR. In 5 of the 23 carriers infected by genotypes I and/or II, antibodies specific for HCV type 1 could not be detected, whereas all 16 carriers infected by genotype IV were serologically typed as type 2. Out of the six carriers infected by HCV of genotype V, all were found to have antibodies of serotype 3, but in most cases together with antibodies to NS5 type 1, indicating sequence homologies between types 1 and 3 of this NS5 region. In the one patient serum where the HCV strain could not be genotyped, a mixture of types 1, 2, and 3 antibodies were found. In conclusion, a serotyping system with a sensitivity and specificity of 89% was developed. It is confirmed that at least three distinct serotypes of antibodies to HCV exist. The major advantage of using four different antigenic regions is that we often obtain high absor‐bance values which are easily interpreted, or multiple reactions which confirm each other. © 19

ISSN:0146-6615    

DOI:10.1002/jmv.1890450110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY

摘要:

AbstractTo evaluate the prevalence of adenovirus strains in human immunodeficiency virus (HlV)‐positive patients and to investigate their possible role in the onset of diarrhea, a total of 103 stools from HIV‐seropositive patients at various stages of infection and 200 stools from sex and age cross‐matched control subjects were examined. Adenovirus prevalence was measured by ELISA as well as conventional and rapid cell culture techniques. Results were compared between patients suffering from diarrhea and those without diarrhea. Adenovirus prevalence was statistically greater in HIV‐seropositive cases than controls (8.7%, 2.5%, respectively). No significant difference was found between HIV‐positive patients with diarrhea and those without gastrointestinal complications (P>0.05). However, a significant difference in adenovirus prevalence was found between HIV‐positive patients with diarrhea and control subjects with diarrhea (P= 0.02). Although viral prevalence varied with the different stages of HIV infection, differences were not statistically significant. In conclusion, although current opinion considers adenovi‐ruses to be no more than opportunistic pathogens, the results of this large‐scale study do not exclude a potential reactivation of latent adenovirus in HIV infection and suggest that further effort should be directed to elucidating such a mechanism if it exists as well as investigating the specific role of certain adenovirus serotypes in provoking diarrhea during later stages of HIV infection. © 1995

ISSN:0146-6615    

DOI:10.1002/jmv.1890450111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1995

数据来源: WILEY