bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of the major late human cytomegalovirus matrix protein pp65 as a target antigen for CD8+ virus‐specific cytotoxic T lymphocytes
Authors: McLaughlin‐Taylor Elizabeth , Pande Hema , Forman Stephen J. , Tanamachi Becky , Li Cheng‐Rong , Zaia John A. , Greenberg Philip D. , Riddell Stanley R. 
Published: March 2007

AbstractPrimary Cytomegalovirus (CMV) infection and reactivation of persistent CMV are associated with significant morbidity and mortality in immuno‐compromised individuals. Although recovery from CMV disease is correlated with the development of CMV‐specific cytotoxic T lymphocytes (CTL), the major viral target antigens to which the response is directed are ill‐defined, though they may comprise viral structural elements. We now identify the CMV matrix protein pp65 as a significant target antigen for CD8+ class I major histocompatibility complex (MHC)‐restricted CMV‐specific CTL derived from the peripheral blood of four of five latently infected individuals. CMV‐specific CTL recognition of pp65 on target cells occurs prior to the onset of viral gene expression and persists throughout the duration of the replicative cycle. Recognition in the absence of viral gene expression suggests that abundant viral protein enters the normal trafficking pathway upon viral penetration and is readily made available to MHC molecules for presentation at the cell surface. Thus pp65 specific CTL may represent an important effector population for early control and limitation of CMV infection and disease. The observation that CMV‐specific CTL can be induced in vitro using peptide fragments derived from pp65 supports the future use and manipulation of this and similar effector populations in a clinical setting. © 1994 Wiley‐Liss, Inc.
Use of confirmatory assays for diagnosis of hepatitis C viral infection in patients with hepatocellular carcinoma
Authors: Mangia Alessandra , Vallari David S. , Di Bisceglie Adrian M. 
Published: March 2007

AbstractSerum samples from 87 patients with hepatocellular carcinoma (HCC) in the United States were tested for evidence of hepatitis C viral (HCV) infection using an immunoblot assay for antibodies to the hepatitis C virus and the polymerase chain reaction to detect HCV RNA. The findings with these assays were compared to those with a first generation enzyme‐linked immunoassay (EIA). Antibody to HCV (anti‐HCV) was detected in 14 patients (16%) by EIA; only eight of these were also positive by immunoblot and four had HCV RNA by reverse transcription polymerase chain reaction (RT‐PCR). An additional four cases, negative by EIA, were found to be positive by immunoblot; two of these had HCV RNA in serum. Evidence of previous hepatitis B viral infection was noted in 15 patients (17%). Only two patients with antibody to hepatitis B core antigen also had anti‐HCV by the immunoblot assay, suggesting that concomitant infection with the hepatitis B and C viruses was not common. Thus, HCV infection appears to play a less important role in the pathogenesis of HCC in the United States than in southern Europe and Japan and other etiologic factors should be sought in this population. © 1994 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
Infectivity titration of a prototype strain of hepatitis E virus in cynomolgus monkeys
Authors: Tsarev Sergei A. , Tsareva Tatiana S. , Emerson Suzanne U. , Yarbough Patrice O. , Legters Llewellyn J. , Moskal Thomas , Purcell Robert H. 
Published: March 2007

AbstractThe infectivity titer of a standard stock of the SAR‐55 strain of hepatitis E virus (HEV) was determined in cynomolgus macaques (Macaca fas cicularis) and the effect of dose on the course of the infection was examined by weekly monitoring of alanine aminotransferase (ALT) and anti‐HEV levels. Antibody to HEV (anti‐HEV) was measured with ELISAs based on ORF‐2 recombinant antigens consisting of either a 55 kDa region expressed in insect cells or shorter regions expressed as fusion proteins in bacteria. The ELISA based on the 55 kDa antigen was generally more sensitive. The infectivity titer of SAR‐55 was 106 cynomolgus 50% infectious doses per gram of feces. The infectivity titer corresponded to the HEV genome titer of the inoculum as determined by reverse transcriptase‐polymerase chain reaction (RT‐PCR). Anti‐HEV IgM was detected in only a portion of the animals that had an anti‐HEV IgG response. Biochemical evidence of hepatitis was most prominent in animals that were inoculated with the higher concentrations of virus and the incubation period to seroconversion was prolonged in animals that received the lower doses. © 1994 Wiley‐Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
Low correlation of human cytomegalovirus DNA amplification by polymerase chain reaction with cytomegalovirus disease in organ transplant recipients
Authors: Weber B. , Nestler U. , Ernst W. , Rabenau H. , Braner J. , Birkenbach A. , Scheuermann E.‐H. , Schoeppe W. , Doerr H. W. 
Published: March 2007

AbstractSeventy‐five organ transplant recipients underwent prolonged virological and serological follow‐up for early detection of human Cytomegalovirus (HCMV) infection after transplantation. HCMV DNA detection by nested polymerase chain reaction (PCR) and HCMV early structural antigen (pp65) detection were carried out in 576 peripheral blood leucocyte (PBL) samples. Furthermore, 563 blood specimens were investigated by a commercially available enzyme‐linked immunosorbent assay (ELISA) for the detection of specific immunoglobulins G, M, and A against HCMV structural antigens.In eight of nine symptomatic organ transplant recipients, HCMV DNA was detected in one or more consecutive blood samples. HCMV DNA PCR was also positive in one or more samples from eight patients who never developed HCMV‐related symptoms. HCMV pp65 antigen was detected almost exclusively in PBL samples from organ transplant recipients suffering from HCMV disease. However, antigenaemia was not detected in four PCR positive patients presenting clinical signs attributable to HCMV infection. Two of the initially HCMV DNA positive samples were not confirmed by retesting and hybridisation.The results of the present study demonstrate that despite the high specificity of nested PCR, HCMV DNA may be detected in the absence of clinical symptoms attributable to HCMV infection. In asymptomatic reactivation, limited replication of viral DNA may be responsible for positive results of PCR without any clinical relevance. In this context, pp65‐antigen detection from PBL seems to have a better prognostic value, but is not always detected when clinical symptoms are present. © 1994 Wiley‐Liss, Inc.
Human papillomavirus DNA and anti‐HPV secretory IgA antibodies in cytologically normal cervical specimens
Authors: Veress György , Konya József , Csiky‐Mészáros Tibor , Czeglédy Judit , Gergely Lajos 
Published: March 2007

AbstractCervical specimens collected from 163 cytologically healthy women were screened for the presence of human papillomavirus (HPV) DNA and anti‐HPV secretory IgA antibodies. HPV DNA was detected by a general primer mediated polymerase chain reaction (PCR), which amplifies a conserved region from the L1 ORF of genital HPVs. The PCR products were typed by restriction enzyme digestion. A total of 35 samples (21.5%) were positive for HPV DNA (13 samples for HPV 6, 6 for HPV 16, 3 for HPV 18, and 13 for untypeable HPV X). HPV DNA positivity was significantly higher among women under 25 years of age (34.8%) than among the older patients (12.4%) (P< 0.001).An enzyme‐linked immunosorbent assay (ELISA) using synthetic peptide antigens was carried out to detect local secretory IgA antibodies against the following HPV specific antigens: HPV 16 E2, HPV 16 E7, HPV 16 L1, HPV 16 L2, and HPV 11 L2. Thirty‐four secretions (20.9%) were found to react with at least one of the oligopeptides. Anti‐HPV IgA positivity was the highest among women aged 25–32 years, and it was significantly lower in both the younger and the older age groups (P < 0.05). Correlation between HPV DNA and anti‐HPV IgA detection was rather weak: anti‐peptide IgA positivity was 34.3% (12 of 35) among HPV DNA positive patients compared to 17.2% (22 of 128) among HPV DNA negative women (P < 0.05). The fluctuating course of latent HPV infections should be considered in evaluating the low level of correlation between HPV DNA and anti‐HPV IgA positivity. © 1994 Wiley‐Liss, Inc.
Typing of human papillomaviruses in cervical carcinoma biopsies from Cape Town
Authors: Williamson Anna‐Lise , Brink Nicola S. , Dehaeck Catherine M. C. , Ovens Samantha , Soeters Robbert , Rybicki Edward P. 
Published: March 2007

AbstractSixty‐eight cervical carcinoma biopsies from women at Groote Schuur hospital in Cape Town were screened for human papillomavirus (HPV) DNA by polymerase chain reaction (PCR) amplification with subsequent typing by hybridisation with specific oligonucleotides. Amplified DNAs which hybridised with the HPV group‐specific oligonucleotide probes, but with none of the type‐specific probes, were categorized as unclassified HPV types. Eighty‐one percent of samples were HPV positive and the following distribution and types were detected: 46% HPV 16, 1.5% HPV 18, 6% HPV 31, 6% HPV 33, 1.5% HPV 45, and 25% unclassified HPVs. Four of the tumours had detectable dual infections with the following combinations of HPVs: HPV31/HPV33; HPV16/ HPV33; HPV18/HPV16; HPV45/HPV33. Tumour DNA from the 17 PCR unclassified HPVs was analysed by Southern blotting and gave the following results: 11 were negative, 4 were positive on hybridisation but could not be typed (unclassified HPV), 1 was HPV 16, and 1 resembled the HPV 16 “variant” described previously [Williamson et al. (1989): Journal of Medical Virology 28:146‐149]. Only 2 of 13 samples that were negative for HPV by PCR were positive for unclassified HPVs by Southern blot analysis. Sequencing of a PCR product revealed that one of the unclassified HPVs was HPV 52. This is the first record of HPV 52 and HPV 45 in Africa. © 1994 Wiley‐Liss, Inc.
Enhanced detection of antibodies to hepatitis C virus by use of a third‐generation recombinant immunoblot assay
Authors: Buffet C. , Charnaux N. , Laurent‐Puig P. , Chopineau S. , Quichon J. P. , Briantais M. J. , Dussaix E. 
Published: March 2007

AbstractFifty‐seven sera with indeterminate results by the second generation RIBA (RIBA 2) for confirmation of hepatitis C virus (HCV) enzyme linked immunoassay (ELISA) reactivity were tested by the new third generation RIBA (RIBA 3). Thirty three (57.9%) displayed reactivity for at least one other band and were therefore classified as positive; two became negative and 22 (38%) remained indeterminate. The incidence of HCV viremia, as determined by the RNA polymerase chain reaction (PCR), was 75% for the latter sera. The data show that it is important to subject RIBA 3 indeterminate samples to PCR. © 1994 Wiley‐Liss, Inc.
Comparison of quantitative cDNA‐PCR with the branched DNA hybridization assay for monitoring plasma hepatitis C virus RNA levels in haemophilia patients participating in a controlled interferon trial
Authors: Bresters D. , Cuypers H. T. M. , Reesink H. W. , Mauser‐Bunschoten E. P. , van den Berg H. M. , Schaasberg W. P. , Wilber J. C. , Urdea M. S. , Neuwald P. , Lelie P. N. 
Published: March 2007

AbstractThe branched DNA (bDNA) assay was compared with a semi‐quantitative cDNA‐polymerase chain reaction (cDNA‐PCR) assay for monitoring HCV RNA levels in plasma in 17 haemophilia patients participating in a controlled a‐interferon trial. Good correlation between the HCV RNA levels as detected by the two assays was observed, with a correlation co‐efficient of 0.83 (P < 0.0001) and 0.90 (P < 0.0001) at week 0 and 24, respectively. Hepatitis C virus RNA (HCV RNA) levels could be assessed with the bDNA assay in 14/17 (82 percent) HCV cDNA‐PCR positive pre‐treatment samples. The bDNA assay apparently failed to detect low viral titres. (riterferon treated patients (n = 11) showed either a complete response, being a large reduction in HCV RNA level to below the detection limit of the HCV cDNA‐PCR assay (6/11) or no significant reduction in HCV RNA level (5/11). A “partial” virological response was not observed. The changes in HCV RNA plasma levels in non‐responders during interferon (IFN) treatment were similar to the (small) natural fluctuations in viral load observed in controls (untreated patients). Although the bDNA assay was not as sensitive as cDNA‐PCR, given its user friendliness and quantitative results, it is concluded that it is a useful test for monitoring HCV RNA levels in patients treated with interferon. However, patients who are non‐reactive in the bDNA assay have to be retested by cDNA‐PCR because low viral titres are not detected by the bDNA assay. © 1994 Wiley‐Liss, Inc.
Detection of respiratory syncytial virus by RNA‐polymerase chain reaction and differentiation of subgroups with oligonucleotide probes
Authors: van Milaan A. J. , Sprenger M. J. W. , Rothbarth Ph. H. , Brandenburg A. H. , Masurel N. , Claas E. C. J. 
Published: March 2007

AbstractThe polymerase chain reaction (RNA‐PCR) was used for specific detection of respiratory syncytial virus (RSV) genomes in clinical specimens. A set of primers was selected from conserved regions of the 1Band N genes for detection of both subgroups. The primers were found to be RSV specific, all RSV strains generated a 218 bp product, and no RSV specific amplified product was obtained when nucleic acids from a variety of micro‐organisms from the respiratory tract were subjected to the RNA‐PCR. We took advantage of the sequence heterogeneity of the amplified products to discriminate between the A and B strains by hybridisation with subgroup specific Oligonucleotide probes. This additional hybridisation assay increased the sensitivity of the RNA‐PCR tenfold. The RNA‐PCR was tested on clinical specimens from children with symptoms of an infection of the respiratory tract. The results were compared with isolation of RSV in cell culture and direct immunofluorescence. From 93 specimens tested, 31 were found positive by all three techniques. Six additional positive results were detected using RNA‐PCR. From these 37 RSV positive specimens 33 (92%), including all 6 additional positives, were subgroup A and only 4 were subgroup B strains.Thus, the RNA‐PCR is a specific and sensitive technique for the detection and subgroup classification of RSV genomes. © 1994 Wiley‐Liss, Inc.
Sequence analysis of proviral HIV RT amplified directly by a semi‐quantitative technique from AZT treated patients
Authors: Stein Christian A. , Levantis P. , Oxford J. S. 
Published: March 2007

AbstractTo minimise possible arbitrary selective effects of culturing HIV, proviral RT DNA was isolated directly from PBMCs of four patients treated for 6–14 months with AZT, RT DNA was amplified by PCR and sequenced directly without further in vitro manipulation. Eighteen changes additional to those 4 or 5 changes previously shown by genetic reconstruction experiments [Kellam et al.: Proceedings of the Nationa Academy of Sciences of the United States of America 89:1934–1938, 1992] were found in the 14 different sequences analysed. Substitutions clustered in two defined areas of the RT, from amino acids 60 to 70 and from 180 to 220. Mutations were observed at each of the two areas independently or at both sites simultaneously. Amino acid changes in RT from patients harbouring resistant strains of HIV‐1 were found in positions 60 (Val), 62 (Ala), 93 (Gly), 100 (Phe), 161 (Pro), 173 (Asn), 177 (Glu), 180 (lle), 181 (Tyr), 182 (Leu), 186 (Asp), 194 (Gln), 196 (Glu), 200 (lle), 209 (Val), 210 (Trp), 211 (Lys), and 214 (Phe) in addition to those described previously. It was anticipated that multiple proviral DNAs would be present in a single clinical sample. Therefore end point dilution PCR methodology was used, which allowed sequence analysis of separate proviral DNA molecules from the patients' proviral DNA. Even in patients who had received AZT for more than 10 months wild‐type “AZT‐sensitive” RTs co‐existed with mutated “AZT‐resistant” RTs in the same patient sample. © 1994 Wiley‐Liss, Inc.
Homologous and heterologous neutralization antibody responses after immunization with Japanese encephalitis vaccine among Taiwan children
Authors: Ku Chia‐Chi , King Chwan‐Chuen , Lin Ching‐Yuang , Hsu Huei‐Chu , Chen Li‐Yen , Yueh Yi‐Yuen , Chang Gwong‐Jen J. 
Published: March 2007

AbstractBecause 21 immunized children (13%) among the 162 confirmed Japanese encephalitis (JE) cases during 1986–1991 occurred in Taiwan, we collected 320 serum samples from Taiwan children aged 15–31 and 27–44 months immediately before the 1st dose (n = 41) and 1–3 months after the 2nd dose (n = 78, 27 pairs), and immediately before (n = 58) and 1–3 months after the 3rd dose (n = 143,44 pairs) to determine neutralization antibody (Nt Ab) against the Nakayama (N) and Beijing‐1 (B) strains and two Taiwan wild type JE viruses (JEV): CC‐27 and CH‐1392. Our Nt results showed that (1) B vaccine stimulated a better homologous Ab response than N vaccine for Nt Ab seropositivity rate (NASR), produced a higher level of Nt titer after the primary immunization [2 doses = 100% vs. 91%, geometric mean titer (GMT) = 115 vs. 22], had a greater booster effect (3 doses: 100% vs. 95%; GMT = 320 vs. 33), and showed a better capability to neutralize two local Taiwan JEV strains, particularly only after 3 doses (ave. NASR for B vs. N = 90% vs. 10%; and GMT for B vs. N = 154 vs. 1); (2) the two wild type JEV strains had different plaque morphology and antigenic variation and the CC‐27 strain was not neutralized as well as the CH‐1392 strain after 3 doses of vaccine (BBB or NNN or NNB); and (3) 30% of the children had lost JEV Nt Ab one year after the 2nd dose of N vaccine and natural infection with JE virus did occur among those children after immunization. In conclusion, (1) three doses of mouse‐brain vaccine are the minimum requirement to protect children against the local Taiwan JEV; (2) the best strain for a JE vaccine depends on level of Nt Ab it induced, the molecular epidemiology and antigenic variation of the JEV in each local area; and (3) future vaccine must produce better B‐ and T‐cell memory. © 1994 Wiley‐Liss, Inc.
Biological and genetic characterization of a hemagglutinating coronavirus isolated from a diarrhoeic child
Authors: Zhang X. M. , Herbst W. , Kousoulas K. G. , Storz J. 
Published: March 2007

AbstractThe coronavirus strain HECV‐4408 was isolated from diarrhea fluid of a 6‐year‐old child with acute diarrhea and propagated in human rectal tumor (HRT‐18) cells. Electron microscopy revealed coronavirus particles in the diarrhea fluid sample and the infected HRT‐18 cell cultures. This virus possessed hemagglutinating and acetylesterase activities and caused cytopathic effects in HRT‐18 cells but not in MDBK, GBK and FE cells. One of four S‐specific monoclonal antibodies reacted in Western blots with HECV‐4408, BCV‐L9 and BCV‐LY138 but not with HCV‐OC43, and two reacted with BCV‐L9 but not with HECV‐4408, BCV‐LY138 and HCV‐OC43. One S‐specific and two N‐specific monoclonal antibodies reacted with all of these strains. cDNA encompassing the 3′ 8.5 kb of the viral RNA genome was isolated by reverse transcription followed by polymerase chain reaction amplification had size and restriction endonuclease patterns similar to those of BCV‐L9 and BCV‐LY138. In contrast, the M gene of HCV‐OC43 differed in restriction patterns from HECV‐4408 and BCV. A genomic deletion located between the S and M within the nonstructural genes of HCV‐OC43 was not detected in HECV‐4408. DNA sequence analyses of the S and HE genes revealed more than 99% nucleotide and deduced amino acid homologies between HECV‐4408 and the virulent wild‐type BCV. Forty‐nine nucleotide and 22 amino acid differences were found between the HE genes of HECV‐4408 and HCV‐OC43, while only 16 nucleotide and 3 amino acid differences occurred between the HE genes of HECV‐4408 and BCVLY138. We thus conclude that the strain HECV‐4408 is a hemagglutinating enteric coronavirus that is biologically, antigenically and genomically more closely related to the virulent BCVLY138 than to HCV‐OC43. © 1994 Wiley‐Liss, Inc.
Serotyping of human rotaviruses in the Tokyo area (1990–1993) by enzyme immununoassay with monoclonal antibodies and by reverse transcription and polymerase chain reaction amplification
Authors: Ushijima Hiroshi , Mukoyama Atsushi , Hasegawa Ayako , Nishimura Shuichi , Konishi Kyoko , Bosu Kim 
Published: March 2007

AbstractSerotyping of human rotavirus in the Tokyo area was conducted from 1990 to 1993 by enzyme immunoassay with monoclonal antibodies (EIAMAbs) against VP7 and by reverse transcription and polymerase chain reaction (RT‐PCR) amplification of the VP4 and VP7 genes.The results by EIA‐MAbs were very similar to those obtained by RT‐PCR. Evidence of intraserotypic variations was suggested because strains of undetermined serotypes were detected by either EIA‐MAb or RT‐PCR. This kind of study is required for vaccine development. © 1994 Wiley‐Liss, Inc.
Genetic diversity of hepatitis B virus strains isolated in Rio de Janeiro, Brazil
Authors: Niel C. , Moraes M. T. B. , Gaspar A. M. C. , Yoshida C. F. T. , Gomes S. A. 
Published: March 2007

AbstractHepatitis B virus (HBV) genomes have been classified into six groups, A–F, group F being the most divergent. South America has provided the smallest number of strains studied at the genome level. The only HBV strain from this region sequenced completely has been classified in group F, and contains the most divergent of the HBV genomes presently known [Naumann et al. (1983): Journal of General Virology 74:1627–1632]. To evaluate genetic relatedness between strains isolated in South America and in the rest of the world, a restriction endonuclease analysis was carried out on 14 HBV strains (4 adw2, 3 adw4, 3 ayw2, and 4 ayw3) isolated in Rio de Janeiro, Brazil. C, pre‐S, and X genes along with the 5′ part of the P gene from these strains were amplified by the polymerase chain reaction. The DNA fragments were digested by BamHI, BstEII, EcoRI, Hhal, and Taql endonucleases. The restriction patterns obtained were compared with those deduced from the nucleotide sequence of 26 HBV strains isolated in other continents. The results showed a large genetic variability of Brazilian strains. Taking into account that all the samples examined possessed the w antigenic subdeterminant, the number of different restriction patterns of strains isolated in Rio de Janeiro was at least as large as that of the reference strains isolated in the rest of the world. Some original restriction patterns were found in adw4 and ayw2 HBV strains.
Hepatitis may precede the occurrence of precore region mutation in hepatitis B virus genome during infection in young carriers
Authors: Xuan‐Thanh Nguyen , Fukuda Ryo , Fukumoto Shiro 
Published: March 2007

AbstractTo understand when the mutation with a stop codon of precore region in hepatitis B virus genome occurs, the prevalence of the mutation of viral DNA clones propagated from sera of school‐age carriers was investigated with respect to hepatitis B e antigen (HBeAg)/anti‐HBe and sequential changes of mutants along HBeAg seroconversion were analyzed.Of 32 carriers aged 8–18 years, 14 HBeAg(+) patients had 2.2% mutant clones, whereas 8 patients with low titer anti‐HBe had a higher rate of 18.1% (P< 0.01) and the highest rate of 61.3% was found in 10 patients with high anti‐HBe titer (P< 0.001). By contrast, the amount of viral DNA decresed significantly in patients with anti‐HBe. Sequential analysis in six cases revealed three types of seroconversion with time difference of the emergence and increase of mutant clones.It is concluded that mutation occurs at a relatively young age and increases along time and/or HBeAg seroconversion. Hepatitis might precede or accelerate the emergence and increse of mutant population which might be predictive of sustained resolution of the disease.