bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of human hemopoiesis by non‐A, non‐B hepatitis virus
Authors: Zeldis Jerome B. , Boender Piet J. , Hellings Jan A. , Steinberg Howard 
Published: March 2007

AbstractAll etiologies of acute viral hepatitis are associated with a transient suppression of hemopoiesis and, rarely, with the development of aplastic anemia. Both hepatitis A and hepatitis B viruses directly inhibit the growth and differentiation of human bone marrow progenitor cells in vitro. We now report a similar effect of a non‐A, non‐B (NANB) hepatitis agent on human bone marrow progenitor cells. Three chimpanzees were inoculated with a putative NANB agent. Coded sera were blindly evaluated for their ability to affect human bone marrow colony formation in vitro. Sera obtained during the acute phase of NANB hepatitis inhibited the in vitro growth of human erythroid (CFU‐E, BFU‐E) and granulocyte‐macrophage (CFU‐GM) progenitor cells, compared with sera obtained before inoculation. Sera obtained after remission of both the biochemical and histological hepatitis and sera obtained from a chimpanzee who underwent biochemical but not histological remission did not inhibit the stem cell assays as much as the acute phase sera. These results suggest an approach to identifying the viremic phase of NANB hepatitis. Inhibition of human bone marrow proliferation appears to be a common property of all known hepatitis viruses.
Restriction to human cytomegalovirus replication in vitro removed by physiological levels of cortisol
Authors: Koment Roger W. 
Published: March 2007

AbstractSince viral infection is in most cases contrary to the survival of the host cell, it is reasonable to assume that cells possess innate viral replication inhibitory mechanisms. Even between strains of permissive cells, degrees of permissiveness are observed. Restriction to human cytomegalovirus (CMV) replication in vitro is well known, especially in epithelioid cells or cells derived from certain organs. We have studied restriction in a fibroblastic strain of human embryonic kidney cells. By treatment of cell cultures with maximum physiologic concentration of the hormone cortisol (25 μg%) both pre and post virus inoculation, susceptibility to laboratory strain Ad169 CMV and low‐passaged clinical isolate JSS CMV was enhanced by factors of 6.4 ± 0.7 and 11.1 ± 0.4, respectively; effectively converting these cells to a totally permissive state. A linear dose response, which peaks at 25 μg% and declines thereafter up to 300 μg%, is evident for both virus strains in this enhancement system. Breakdown of restriction increases in linear fashion with increasing time of cortisol pretreatment of cells. The characterization of cortisol effects converting restrictive human fetal cells in vitro to the permissive state further indicates that human hormones may play a significant role in CMV susceptibility in vivo.
Antigenic relationships between attenuated and pathogenic strains of junin virus
Authors: Candurra Nélida A. , Damonte Elsa B. , Coto Celia E. 
Published: March 2007

AbstractAntigenic relationships between attenuated and pathogenic strains of Junin virus (JV) were investigated. Five strains of either human or rodent origin were tested by cross‐neutralization assay with hyperimmune antisera, raised in rabbits, against each strain. Polyclonal antisera could be used to distinguish among these JV strains, as the titer values differed significantly with ratios of homologous to heterologous titers, which ranged from 1.3 to 22.3. This demonstrates, independent of their virulence, a heterogeneity among the JV strains tested. The relatedness among JV strains was expressed quantitatively through a dendrogram based on taxonomic distance coefficients. The field strains of JV were grouped into two clusters, according to their geographic origin.
Quantitation of hepatitis B viral DNA by solution hybridization: Comparison with DNA polymerase and hepatitis B e antigen during antiviral therapy
Authors: Kuhns Mary C. , McNamara Anne L. , Perrillo Robert P. , Cabal Carlos M. , Campbell Carolyn R. 
Published: March 2007

AbstractSerological markers of hepatitis B virus (HBV) replication were assessed in a randomized, controlled trial of prednisone withdrawal followed by α ‐interferon in the treatment of chronic hepatitis B. HBV DNA levels in more than 700 serial serum samples from 41 patients were determined by a sensitive and quantitative solution hybridization assay. Results were compared with HBV DNA polymerase (DNAp) activity and hepatitis B e antigen (HBeAg) in 21 untreated controls and 20 treated patients.Among treated patients, the mean pretherapy HBV DNA values were higher in nonresponders than in responders. During prednisone treatment, DNA levels increased an average of 2.1‐fold in responders and 1.4‐fold in nonresponders. During the 2‐week rest interval between prednisone and interferon, DNA values fell an average of 57% in responders. In contrast, the mean DNA values in nonresponders did not change during the same interval. This early distinction between responders and nonresponders was not apparent from DNAp or HBeAg results. During interferon treatment, HBV DNA became undetectable in responders and remained negative during a 1‐year follow‐up. DNA in nonresponders declined to 14% of baseline during interferon treatment but increased to pretherapy levels after treatment.DNAp values generally paralleled HBV DNA values, but DNAp activity showed more variability and lower sensitivity than did the hybridization assay results. HBeAg values varied independently of HBV DNA and DNAp with a much delayed decline in responders.These results indicate that HBV DNA, when measured quantitatively by a sensitive solution hybridization assay, is an early predictor of the effects of antiviral agents on replication.
Measurement of avidity of specific IgG for verification of recent primary rubella
Authors: Hedman Klaus , Rousseau Steve A. 
Published: March 2007

AbstractSixty‐four subjects' serum samples, positive or equivocal by rubella IgM assays and containing rubella IgG, were examined for the avidity of rubella IgG. Four of the sera originated from rubella reinfections; others had false‐positive IgM results due to interference by parvovirus infection or by other mechanisms; and the remaining were sera from the acute phase or convalescence of primary rubella. A novel IgG avidity test, avidity‐ELISA, and a semiquantitative haemolysis typing assay were used. According to the avidity‐ELIA, 29 subjects had recent primary rubella (low IgG avidity), and another 29 had previous rubella immunity (high IgG avidity), whereas 6 serum samples gave borderline avidity values. Comparison of these results with pre‐existing clinical records and laboratory data showed that all samples with low IgG avidity were obtained during or shortly after acute primary rubella. All sera with high IgG avidity originated from the previously immune subjects; the rubella reinfections were confined within this group. Five of the six sera with borderline avidity values were obtained within 2 months from primary rubella. In conclusion, the measurement of IgG avidity is a powerful tool for the distinction of acute or recent primary rubella from pre‐existing rubella immunity, including rubella reinfections.
Detection and typing of human papillomavirus infection of the uterine cervix by dot blot hybridisation: Comparison of scrapes and biopsies
Authors: Hallam Nicholas , Gibson Patricia , Green Jonathan , Charnock Mark 
Published: March 2007

AbstractPaired scrapes and biopsies from 100 women attending a routine colposcopy clinic were examined by dot blot DNA hybridisation for infection with human papillomavirus (HPV) types 6/11,16,18, and 31;51% of the scrapes and 50% of the biopsies were positive for HPV infection. Scrapes detected more HPV 18 (10% vs. 2%, P = < 0.05) and HPV 31 (7% vs. 3%, not significant) than did the biopsies, but biopsies detected more HPV 16 (42% vs. 33%, not significant). Comparison of the results for each patient revealed that the correlation between scrapes and biopsies was not very close: only 34 patients were HPV‐positive by both sampling methods, whereas 67 were positive if the results were combined. This report discusses the implications of these findings.
Rapid detection of varicella‐zoster virus in clinical specimens using monoclonal antibodies on shell vials and smears
Authors: Meulenberg Janneke J. M. , Schirm Jurjen , Pastoor Geke W. , Schröder F. Peter , Van Vader Pieter C. Voorst 
Published: March 2007

AbstractMonoclonal antibodies were used for detecting varicella‐zoster virus (VZV) by immunofluorescence (IF) in clinical specimens inoculated on shell vial cultures. Vesicles of 74 patients with varicella or herpes zoster‐like eruptions were tested by this method and by conventional cell culture. Further diagnostic tests were direct IF on smears (42 patients), the cytological Tzanck test (28 patients), and serology (30 patients). Both IF assays were performed with the commercial VZV‐specific monoclonal antibody 3B3 (Ortho). Using the shell vial technique, we found VZV in 37 (50%) of the patients, on average after 3 days. The conventional culture method yielded 26 positives (35%), on average after 7.5 days.Twenty‐nine of the shell vial IF‐positive patients were also positive by direct IF on smears (30 tested), while 15 gave positive Tzanck smears (18 tested). The sensitivities of the shell vial IF test, the direct IF test, the conventional culture method, and the Tzanck test were about 95%, 97%, 70%, and 79%, respectively. For the specificities, we found at least 97% for the shell vial IF test, at least 91% for the direct IF test, and about 78% for the Tzanck test. We conclude that both VZV IF tests are much more reliable than the conventional cell culture method and the Tzanck test for the laboratory diagnosis of VZV infections.
Antibodies against varicella‐zoster virus and herpes simplex virus deoxythymidine kinase in heterologous infections
Authors: Källander C. F. R. , Torfason E. G. , Diderholm H. , Gronowitz J. S. , Olding‐Stenkvist E. , Sundqvist V.‐A. 
Published: March 2007

AbstractAntibody responses to varicella‐zoster virus (VZV) deoxythymidine kinase (dTK) and herpes simplex virus (HSV) dTK in homologous and heterologous infections were studied. Antibodies blocking the enzymatic activity of VZV‐dTK appeared late after varicella and decreased more or less in parallel with the decreasing complement fixing [CF] titre. In herpes zoster, on the other hand, antibodies to VZV‐dTK appeared soon after infection. Antibodies against HSV dTKs appeared long after primary infection, but they were subsequently present in all other HSVCF positive sera. In recurrent HSV, all acute sera were already HSV‐dTK antibody positive, and three of nine persons showed an increase in titer between their acute and convalescent sera. Blocking antibodies to VZV‐dTK appeared rapidly in specimens from three of 18 individuals positive by an immunofluorescence VZV‐immunity test during HSV infection, whereas all other specimens remained devoid of blocking antibodies against VZV‐dTK. A rise in antibody titre against HSV‐dTK during VZV infections was observed in serum specimens from three of 13 HSV‐CF positive patients, whereas an antibody response against HSV‐dTK was not found in HSV‐CF negative individuals in conection with VZV infections. The relevance of the sporadic increase in the titres of antibodies against heterologous viral dTKs is discussed.
Infection by enteric adenoviruses, rotaviruses, and other agents in a rural african environment
Authors: Tiemessen Caroline T. , Erasmus Marietha J. , Kidd Alistair H. , Wegerhoff Frank O. 
Published: March 2007

AbstractFrom February 1985 to January 1986, 432 stool samples, 310 from rural African children with diarrhea and 122 from controls, were analysed for the presence of enteric viruses known to be associated with diarrhea. Group A rotavirus ELISA indicated 12.9% positivity among patients and 2.5% positivity among controls. Only 23 of the 43 rotavirus ELISA‐positive stools were also positive by electron microscopy. Nine children, three of whom were controls, were found to be shedding coronavirus‐like particles, detected by electron microscopy. Stools from all but one of the nine children had been taken within 1 month of each other. Dot‐blot hybridization tests for the presence of Ad40 or Ad41 DNA revealed 44 positive stools, 41 of which were from patients (13.2% positivity). Only three of the Ad40‐ or Ad41‐positive stools by DNA hybridization were positive by electron microscopy, and only these three strains could be grown in semipermissive Chang conjunctival cells and their identity checked by restriction enzyme analysis. Further attempts to rescue the other strains using a helper virus failed, but nine of the stools proved positive by ELISA using a subgroup F‐specific monoclonal antibody. On the basis of the DNA hybridization results alone, subgroup F adenoviruses were encountered as frequently as rotavirus in the study and were significantly associated with diarrhea, although the viability and intactness of virus particles by the time of laboratory analysis appeared to be very low.
Electron microscopy of ribonucleic acid in nuclear particulate aggregates of hepatitis d using nuclease‐gold complexes
Authors: Kojima Takashi , Callea Francesco , Shikata Jan Desmyter, Toshio , Desmet Valeer J. 
Published: March 2007

AbstractThe ultrastructural localization of hepatitis delta antigen (HDAg) and ribonucleic acid (RNA) was investigated by immunoperoxidase electron microscopy and by enzyme electron microscopy of RNase‐gold complexes on liver biopsies from seven patients with hepatitis D. HDAg was localized mainly in the nucleus and sometimes in the cytoplasm of hepatocytes. Ultrastructurally, intranuclear HDAg was found on nuclear particulate structures measuring 20 to 30 nm in diameter. Intranuclear RNA visualized with gold particles was found in high amounts in the nucleolus, to a small extent in the chromatin area, and also on nuclear particulate structures. These findings suggest that intranuclear aggregates of irregular granular particulate structures in hepatitis D are the internal component of hepatitis delta virus (HDV) particles in blood.
Detection of neutralizing igm antibodies in the diagnosis of enterovirus infections
Authors: Gaudin Odette‐Germaine , Pozzetto Bruno , Aouni Mahjoub , Ros Alain 
Published: March 2007

AbstractData are presented of IgM detection by a neutralization test used routinely in 1,062 patients. Antigens isolated during the period of investigation were EV4, EV7, EV11, EV18, EV21, EV24, EV33, CA9, CB2, CB4, and CB5. No difference was observed in the distribution of IgM‐positive sera according to age and sex. Total antibodies are at higher titres when IgM antibodies are present. Polytypic IgM responses are not frequent (less than 10%). The frequency of the IgM‐positive sera for a given serotype correlated with the frequency of isolates for the serotype except for CA9. Other than for babies under age 6 months, IgM detection is more frequent than is isolation. The susceptibility of the elderly and the frequency of IgM‐positive sera among adults over age 40 years suggests possible underestimation of enterovirus infections in adults. The duration of IgM remains a major question.
Detection of human papillomavirus deoxyribonucleic acid by filter in situ hybridization during pregnancy
Authors: Czeglédy Judit , Gergely Lajos , Endrödi Imre 
Published: March 2007

AbstractSamples taken from 101 healthy pregnant women (49 over and 52 under the 20‐week gestational period) and 108 healthy nonpregnant women were tested for human papillomavirus (HPV) types. Using 6, 11, 16, and 18 HPV DNA probes, 3‐5 x 105 exfoliated cells scraped from the cervix were tested by filter in situ hybridization (FISH). Thirty‐five of the pregnant women (34.6%) had evidence of the presence of HPV DNA: with 11.8% (12/101) HPV 6; 7.9% (8/101) HPV 11; 8.9% (9/101) HPV 16; and 5.9% (6/101) HPV 18 positivity. HPV DNA was detected in 20.4% (22/108) of the non‐pregnant women.Compared with the healthy, nonpregnant group, the higher level of asymptomatic cervical HPV infection was mainly due to the accumulation of HPV 16 and 18 nucleic acids during the gestational period: with detection of HPV 16 in 8/49 cases (16.3%) and of HPV 18 DNA sequences in 4/49 (7.6%) cases. Screening 6‐8 weeks after delivery indicated a decline of HPV positivity.Of the 4/12 HPV type 16 positive mothers, only one retained the presence of HPV 16 DNA, whereas neither of the 2/12 type 18 positive women reacted after birth with the type 18 radioactive probe.
Diagnosis of hepatitis a and b by testing saliva
Authors: Parry John V. , Perry Keith R. , Mortimer Philip P. , Panday Sohrab 
Published: March 2007

AbstractThe use of salivary samples to diagnose acute viral hepatitis was investigated. Tests for IgM antibody to hepatitis A virus (anti‐HAV) on 29 acute‐phase samples from serologically confirmed cases of hepatitis A were strongly reactive. Follow‐up samples indicated that IgM anti‐ HAV persisted at moderate levels for 2‐4 months and was not usually detectable thereafter. The ratio of IgM to IgG anti‐HAV (RIA index) correlated closely with the interval from onset of infection. Significant levels of IgM anti‐HAV were not detected in the saliva of 103 IgG anti‐ HAV positive and 102 IgG anti‐HAV negative individuals nor of 4 individuals with hepatitis B. Similarly, IgM anti‐HBc was present in the saliva of acute cases of hepatitis B, but not in the saliva of 25 IgG anti‐HBc positive and 85 IgG anti‐HBc negative individuals, nor of 24 individuals with recent hepatitis A.It is concluded that saliva is a convenient and satisfactory alternative to serum for the diagnosis of hepatitis A infection.
Detection of hepatitis a virus rna in serum from patients with acute hepatitis
Authors: Oren R. , Shouval D. , Tur‐Kaspa R. 
Published: March 2007

AbstractHepatitis A virus (HAV) RNA was extracted from the sera of patients with acute hepatitis and then detected by molecular hybridization using cloned HAV complementary DNA (cDNA). HAV RNA was detected in 20 of 85 patients with acute HAV infection, mainly during the prodromal stage, or early during the icteric phase of the disease; it was detected as long as 21 days after its initial detection. Patients with HAV RNA in the serum had a significantly higher titer of anti‐HAV IgM.
Control of HBV and HDV infection in an isolated pacific Island: 1. pattern of infection
Authors: Speed Bryan R. , Dimitrakakis Mary , Thoma Kiki , Gust Ian D. 
Published: March 2007

AbstractHepatitis B virus (HBV) and hepatitis delta virus (HDV) infections are known to be hyperendemic in Nauru. Because of the consequences of chronic HBV infection, the Nauruan Government has commenced a program that aims to reduce and eventually eliminate hepatitis B infection by immunizing susceptible adults and children on the island and every newborn baby. At the outset of this program, a national seroepidemiological survey was undertaken. Eighty‐eight percent of the population were tested, of whom 69.1% had markers of HBV infection. Evidence of superinfection with HDV was found in 22.7% of HBV carriers, with the highest prevalence in adolescents and young adults. All seronegative individuals were offered three doses of plasma derived hepatitis B vaccine.A post‐vaccination survey of 64% of those vaccinated showed that 98% had developed circulating antibodies.
Use of anticontamination primers in the polymerase chain reaction for the detection of human papilloma virus genotypes in cervical scrapes and biopsies
Authors: Van Den Brule Adriaan J. C. , Claas Eric C. J. , Maine Marc Du , Melchers Willem J. G. , Helmerhorst Theo , Quint Wim G. V. , Lindeman Jan , Meijer Chris J. L. M. , Walboomers Jan M. M. 
Published: March 2007

AbstractA reliable application of the polymerase chain reaction (PCR) for detection of the human papilloma virus (HPV) genotypes in cervical smears and biopsies was developed. Primers flanking the HPV cloning site were used to avoid detection of cloned HPV plasmids. These anticontamination primers were used for the specific detection of HPV 6, 11, 16, 18, and 33 in cervical scrapes that had been tested previously for HPV with a combined modified filter in situ hybridization (modified FISH) and dot blotting procedure. The PCR appeared to be superior. Two groups of women were screened for HPV genotypes. Group A consisted of women belonging to a regularly screened population, and group B contained women attending a gynaecological clinic. It appeared that the overall prevalence of HPV in cytologically normal scrapes in the first group was 6%, whereas in the second group 12% was found. In scrapes with cytological dysplasia, the prevalence of HPV in group A and B was approximately 40% and 60%, respectively. HPV 16 was present predominantly. In biopsies of squamous cell carcinomas of the cervix uteri, an HPV prevalence rate of 90% was found, all of which contained only HPV 16 and 18. These data indicate an important role for HPV detection in the screening of cervical scrapes to identify women with an increased risk of cervical cancer.
Biological response modifier enhances the activity of natural killer cell against human cytomegalovirus‐infected cells
Authors: Murayama Tsugiya , Natsuume‐Sakai Shunnosuke , Xu Bin , Furukawa Toru , Rinaldo Charles R. 
Published: March 2007

AbstractPeripheral blood lymphocytes (PBL) from two human cytomegalovirus (CMV)‐seronegative donors and eight CMV‐seropositive donors were cultured for 3 days with or without the biological response modifier OK‐432 and examined for lysis of K562 cells and CMV‐infected MRC‐5 cells. OK‐432–stimulated PBL exhibited significantly greater natural killer (NK) activity than did unstimulated PBL. There was no difference in activity of NK cells in PBL prepared from CMV‐seronegative and ‐seropositive donors. Antibody‐complement depletion studies suggested that OK‐432–stimulated NK activity was associated with Leu‐7–positive cells. The ability of OK‐432 to sustain the NK activity in PBL was decreased when the CD4‐positive population of lymphocytes was eliminated by antibody‐complement depletion prior to OK‐432 stimulation. The ability of OK‐432 to sustain the NK activity of PBL was also significantly decreased in the presence of monoclonal antibody against recombinant human interleukin‐2. The results suggest that the activity of human NK cells against K562 and CMV‐infected MRC‐5 target cells can be sustained in vitro by OK‐432‐stimulated T‐helper cells and that the effect of the T‐helper cells is mediated, at least in part, by interleukin‐2.
Trans‐Regulation and differential cell specificity of human papillomavirus types 16, 18, and 11 cis‐acting elements
Authors: Marshall Trudy , Pater Alan , Pater Mary M. 
Published: March 2007

AbstractThe noncoding region (ncr) of human papillomavirus (HPV) types 16, 18, and 11 contains promoter and/or enhancer function. We have localized the sequence containing the constitutive enhancers of HPV types 16, 18, and 11 to 315, 230, and 213 bp fragments, respectively, for comparative studies. The region of homology shared between the enhancers of the three viruses is limited to the sequence ATTTTTGGCTT, which is also present in the ncr of HPV 6b and 33. We have also examined the enhancer activity of the HPV ncrs in three human cervical carcinoma cell lines, one noncervical human carcinoma cell line, and one monkey kidney established cell line. We observed cell‐specific differences in the constitutive expression of the enhancers in the various cell lines. The conditional enhancer activity of the ncr of the viruses is increased in trans by the E2 gene product of HPV 16. Transactivation by E2 is mediated through the E2 binding motif on HPV enhancer plasmids with a heterologous but not with a homologous promoter. Our preliminary studies also indicate a repressor function for the E7 gene of HPV 16.