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prevalence of antibodies against hepatitis a virus, hepatitis b virus, and treponema pallidum in mauritius.a seroepidemiological study on the prevalence of antibodies against hepatitis a virus (hav), hepatitis b virus (hbv) and treponema pallidum was conducted in various groups of the population of the state of mauritus (islands of mauritus and rodrigues). 618 sera were tested. the overall prevalence of anti-hav was 86.1% and yielded and age-dependent increase. serological evidence for acute or chronic hbv infection was found in 3.8%; 4.5% were positive for anti-hbc alone, and in 12.6% past hbv infec ...19911662829
kinetic study of the replication of a cell-culture-adapted hepatitis a virus.the kinetics of replication of hepatitis a virus (lcdc-01) was studied in foetal rhesus monkey kidney cells (frhk-4). cells infected at a multiplicity of infection (moi) of 2.0 showed no viral antigen production until 12 h post-infection using radioimmuno assay (ria); however, at 48 h post-infection a logarithmic increase in antigen concentration began, which peaked by day 7. similar patterns were observed with cultures infected with lower moi (0.20 and 0.02) but events were delayed by about 24 ...19911663259
hepatitis a virus and hepatitis a infection. 19911645494
baseline seroepidemiology of hepatitis a virus infection among children and teenagers in italy.during the period from may 1987 through november 1989, the prevalence of antibodies to hepatitis a virus infection (anti-hav) was assayed by the elisa method in the serum samples of 5,507 (54% males, 46% females) apparently healthy subjects three to 19 years old in italy. subjects were selected by a systematic cluster sampling in five different geographical areas of italy. the overall prevalence of anti-hav was 9.5%; it increased from 2.3% among children three to five-years-old to 16.3% in teena ...19911646772
acute sporadic hepatitis in sudanese children.eighty consecutive cases of acute viral hepatitis and 80 controls selected from a public pediatric clinic were entered into a study of acute sporadic hepatitis in khartoum, sudan. study subjects were 14 years of age or younger and were mainly from a low socioeconomic level. non-a, non-b hepatitis was diagnosed by exclusion in 35 (43.8%) patients, hepatitis a in 27 (33.8%), acute hepatitis b in 8 (10.0%), possible epstein-barr virus (ebv) hepatitis in 1 patient; and dual hepatitis a and b infecti ...19911646853
age-specific prevalence of hepatitis a virus infection among teenagers in sardinia.in 1989, the prevalence of antibodies to hepatitis a virus (anti-hav) in a sample of 1350 sardinian teenagers aged 14 to 19 years was estimated by elisa method. the overall anti-hav prevalence was 20%; it increased from 12.3% among 14-16 year old subjects to 27.4% in subjects aged 17-19 years (p less than 0.01). a slight female preponderance was observed (22.1% versus 17.9) but no statistically significant difference was attained. compared with the corresponding figure (71.6% of prevalence rate) ...19911648657
effect of relative humidity and air temperature on survival of hepatitis a virus on environmental surfaces.stainless steel disks (diameter, 1 cm) were contaminated with fecally suspended hepatitis a virus (hav; strain hm-175) and held at low (25% +/- 5%), medium (55% +/- 5%), high (80% +/- 5%), or ultrahigh (95% +/- 5%) relative humidity (rh) at an air temperature of 5,20, or 35 degrees c. hav survival was inversely proportional to the level of rh and temperature, and the half-lives of the virus ranged from greater than 7 days at the low rh and 5 degrees c to about 2 h at the ultrahigh rh and 35 degr ...19911649579
parameters influencing the attachment of hepatitis a virus to a variety of continuous cell lines.we have investigated the interactions of purified radiolabelled hepatitis a virus (hav) with a variety of continuous cell lines. virus labelled either in vitro with radiolabelled iodine or in vivo with radiolabelled uridine bound to cells with similar efficiency. attachment to bs-c-1 cells was calcium ion-dependent and this correlated with infectivity assay results. the cell tropism of hav attachment was examined using cell suspensions and confluent cell monolayers at both 4 degrees c and 37 deg ...19911649900
simian hepatitis a virus (hav) strain agm-27: comparison of genome structure and growth in cell culture with other hav strains.fragments of cdna representing greater than 99% of the entire genome of wild-type hepatitis a virus (hav) strain agm-27, isolated from an african green monkey, were obtained by the polymerase chain reaction and sequenced. comparison with other hav isolates revealed differences in the predicted amino acid sequence in functionally critical parts of the genome. comparison of the biological properties of agm-27 with those of human wild-type and cell culture-adapted hm-175 strains revealed that agm-2 ...19911649901
sequence analysis of a new hepatitis a virus naturally infecting cynomolgus macaques (macaca fascicularis).a new isolate of hepatitis a virus (hav), cy-145, was isolated from stool specimens obtained from cynomolgus macaques naturally infected with this agent. sequence analysis of the capsid region of the genome indicated that this virus differed from other sequenced hav strains by about 20% at the nucleotide level and 7% at the amino acid level. two amino acid residues (residues 70 of vp3 and 102 of vp1), previously identified as constituting an immunodominant site and conserved in all sequenced hav ...19911649902
[the modelling of hepatitis a in macaques].characteristics of experimental hepatitis a in macaca fascicularis and m. mulatta produced with hav, strain mp, isolated from m. mulatta in an outbreak of spontaneous hepatitis are presented. the hav-mp strain induced the disease in all the animals used in the experiment. the infection was manifest, with all virological, serological, biochemical and morphological features typical of hepatitis a. in m. mulatta, the process was protracted, with virus persistence in feces for at least 4 months. mod ...19911650062
prevalence of antibody to hepatitis c virus among saudi arabian children: a community-based study.in a population-based survey, 39 (0.90%) of 4,496 saudi arabian children (ages 1 to 10) were positive for antibody to hepatitis c virus. no significant difference was seen between the prevalence rate in males (0.9%) and females (0.8%) or between urban (0.7%) and rural dwellers (1.0%). a significant variation of rates (0% to 5.7%) was seen from one region to another. the gizan population, noted for hyperendemic hepatitis b virus infection, had the highest prevalence of antibody to hepatitis c vir ...19911650324
hepatitis a outbreak in a neonatal intensive care unit: risk factors for transmission and evidence of prolonged viral excretion among preterm infants.an outbreak of hepatitis a virus (hav) infection in a neonatal intensive care unit (nicu) provided the opportunity to examine the duration of hav excretion in infants and the mechanisms by which hav epidemics are propagated in nicus. the outbreak affected 13 nicu infants (20%), 22 nicu nurses (24%), 8 other staff caring for nicu infants, and 4 household contacts; 2 seropositive infants (primary cases) received blood transfusions from a donor with hav infection. risk factors for infection among n ...19911651359
mutations responsible for adaptation of hepatitis a virus to efficient growth in cell culture.chimeric genomes of hepatitis a virus strain hm-175 were constructed from cdna clones of the wild-type virus and its cell culture-adapted variant. rna transcribed in vitro from each construct was assayed for infectivity by transfection of cultured cells. rna transcribed from the wild-type cdna clone was minimally infectious and produced virus that grew inefficiently in vitro, whereas that transcribed from certain chimeric genomes consistently produced virus that grew efficiently in cultured cell ...19911651411
the influence of dental status on the detection of igg class anti-viral antibodies in human saliva.an antibody-capture radioimmunoassay was used to measure levels of igg class antibodies to rubella and hepatitis a viruses in serum and saliva of 30 edentulous, 30 partially dentate and 31 dentate individuals. the prevalence of seropositivity for rubella was 98.9 per cent and for hepatitis a 73.6 per cent. the serum reactivities were generally greater than those for saliva. there were 8 false-negative results for saliva out of the 182 tests performed, of which 4 were in the edentulous group, 3 i ...19911652241
[the synthetic peptide 62-75 vp3 of the hepatitis a virus induces virus-binding antibodies].peptide (p6) representing amino acids 62-75 of hav capsid protein vp3 was synthesized. pure p6, octamer form of p6, and p6 conjugated to klh were injected into rabbits. the sera against these preparations reacted with denaturized vp3 in immunoblotting tests; however, only anti-p6-klh serum was capable of binding the native hav.19911652865
[the chronic course of spontaneous and experimental hepatitis a in rhesus monkeys with viral persistence].the prolonged (up to 2 years) complex observation of 11 rhesus macaques (macaca mulatta) with spontaneous hepatitis a and 14 rhesus macaques with experimental hepatitis a developing after their intravenous and/or oral infection with human hepatitis a virus (hav). both natural and experimental infection took a chronic course (15-18 months). in 13 monkeys showing morphological changes in the liver during the whole period of the disease elevated enzyme levels in the blood and virus shedding in fece ...19911653510
treatment of fulminant viral hepatic failure with prostaglandin e. a preliminary report.the effect of prostaglandins (pg) in patients with fulminant and subfulminant viral hepatitis was studied. seventeen patients presented with fhf secondary to hepatitis a (n = 3), hepatitis b (n = 6) and non-a, non-b (nanb) hepatitis (n = 8). fourteen of the 17 patients had stage iii or iv hepatic encephalopathy (he). at presentation, the mean ast was 1844 +/- 1246 units/liter, bilirubin 232 +/- 135 mumol/liter, pt 34 +/- 18 and ptt 73 +/- 26 sec, and coagulation factors v and vii were 8 +/- 4 an ...19911903342
[a comparative study of the sensitivity and specific activity of an immunoenzyme test system for determining class-m antibodies to the hepatitis a virus].the diagnostic value of the first experimental production batches of assay kit "diagn-a-hep", produced at the institute of poliomyelitis and viral encephalitides (ussr acad. med. sci.) and intended for the determination of igm to hepatitis a virus (hav) in the enzyme immunoassay (eia), has been studied in comparison with that of the internationally known and widely approved commercial eia system "havab-meia" for the determination of antibodies to hav (the product of abbott, usa). the study has r ...19911882626
epidemiologic patterns of wild-type hepatitis a virus determined by genetic variation.hepatitis a virus (hav) isolates from different parts of the world are a single serotype. however, genetic analysis of the vp1 genome region of published hav sequences suggested that distinct genotypes of hav could be defined based upon the geographic source of the original isolates. to circumvent the process of cell culture adaptation or animal passage, a 247-bp segment within the vp1 genome region of wild-type hav was amplified by reverse transcription followed by polymerase chain reaction amp ...19911846392
rapid completion of the replication cycle of hepatitis a virus subsequent to reversal of guanidine inhibition.the single-cycle replication kinetics of hepatitis a virus (hav: hm175 p39) in bs-c-1 cells were examined by rna hybridization and vp1 immunoblot assays. viral products accumulated after 4 days of lag phase and reached a plateau by 12 days postinfection. defective, subgenomic rnas were not detected by northern blot analysis of cytoplasmic extracts from infected cells or purified virions. replication of this hav strain was markedly inhibited by 2 mm guanidine. neither the virion itself nor the ad ...19911846497
safety and immunogenicity of a live attenuated hepatitis a virus vaccine in seronegative volunteers.seronegative adults were enrolled in a dose-escalating study of a live attenuated hepatitis a virus (hav) vaccine that was prepared from the f' variant of hav strain cr326f. they were injected subcutaneously with 10(4.1), 10(5.2), 10(6.1), or 10(7.3) tcid 50 of hav vaccine (n = 40) or with placebo (n = 12) and were followed for 6 months. none of the vaccine recipients developed significant systemic reactions or aminotransferase elevations. hav was not isolated in cell culture from any postvaccin ...19911849160
differential diagnosis of acute viral hepatitis using rapid, fully automated immunoassays.we report the development of three rapid, fully automated immunoassays allowing the differential diagnosis of acute viral hepatitis. these assays detect hbsag, igm antibody to hepatitis b core antigen (igm anti-hbc) and igm antibody to hepatitis a virus (igm anti-hav) using the imx instrument system. all imx assays were run in less than 45 minutes and all steps were fully automated including specimen dilution steps. specimens from blood donors, diagnostic and hospital patients, and individuals w ...19911880494
hepatitis a virus infection among homosexual men. 19912059724
[guillain-barré syndrome following acute hepatitis a].a case of guillain-barré syndrome in a 39-year-old male is described. he was admitted to our hospital because of type a acute hepatitis. five days after admission, he developed a progressive weakness of limbs. one week later, he also developed dysphagia and dyspnea. however, after 7 weeks almost all abnormal signs and symptoms disappeared. ha-igm antibody and ha antibody in csf was detectable and then decreasing with neurologic improvement. this finding suggests that guillain-barré syndrome may ...19912060247
[basic factors affecting the development of chronic hepatitis b virus infection].the authors followed up for a period of five years 276 convalescents after viral hepatitis b where all remained carriers of hbsag. the group comprised 108 cases of chronic persisting hepatitis, 134 cases of chronic active hepatitis, 13 cirrhoses of the liver and 21 symptom-free carriers of hbsag. in the group of chronic active hepatitis at the onset of the investigation 128 were hbeag positive. in the course of five years in 43 patients seroconversion to hbeag negativity occurred. thus an annual ...19912025893
[synthesis and immunochemical properties of oligopeptides--fragments of capsid proteins of the hepatitis a virus].the hepatitis a virus (hav) capsid protein vp1, vp2 and vp3 are exposed at the virion surface and should therefore contain antigenic determinants. algorithms for hydrophilicity, antigenicity and flexibility were used to predict probable antigenic sites. synthesis of 7- to 23-membered overlapping peptides from seven sites, viz., 1-11, 1-17, 2-33, 11-25, 73-82, 76-86, 98-109, 98-112, 102-107, 102-108, 108-127, 113-123, 118-140, 276-298 from vp1, 42-62 from vp2, 76-85 from vp3, and 1-23 from vp4, w ...19911724368
proteolytic activity of hepatitis a virus 3c protein.although the genome organization and overall structure of hepatitis a virus are similar to those of other picornaviruses, nothing is known about the protein-processing pathways used by this virus to generate its capsid and nonstructural proteins from the polyprotein precursor. rna transcripts of cloned hepatitis a virus cdnas representing parts of the p2 and p3 regions of the genome were translated in rabbit reticulocyte lysates in vitro, and the translation products were analyzed by sodium dode ...19911850033
characterization of a hepatitis a virus strain suitable for vaccine production.a novel isolate of hepatitis a virus, obtained from a clinical sample, has been adapted to grow on cultured human diploid cells. growth and purification parameters have been optimized to obtain conditions suitable for the development of an inactivated vaccine. the entire viral genome was molecularly cloned, and the gene encoding the vp3 capsid protein was expressed in escherichia coli. the resulting recombinant vp3 was used to obtain rabbit antisera which recognize the denatured protein in purif ...19911668326
hepatitis a virus concentrations in immunoglobulin preparations. 19911671503
declining prevalence of antibodies to hepatitis a virus infection in iceland.the prevalence of antibodies to hepatitis a virus (anti-hav) was investigated in 445 outpatients in iceland in 1987. no difference in anti-hav prevalence according to sex or residence was found. the prevalence rates were low in persons less than 50 years with a sharp increase in persons greater than or equal to 50 years. the prevalence of anti-hav was now significantly lower in the age groups of 40-49 years and 50-59 years than in 1979 indicating a cohort effect. these findings correspond to a m ...19911649491
antigenic and genetic variation in cytopathic hepatitis a virus variants arising during persistent infection: evidence for genetic recombination.variants of hepatitis a virus (phm175 virus) recovered from persistently infected green monkey kidney (bs-c-1) cells induced a cytopathic effect during serial passage in bs-c-1 or fetal rhesus kidney (frhk-4) cells. epitope-specific radioimmunofocus assays showed that this virus comprised two virion populations, one with altered antigenicity including neutralization resistance to monoclonal antibody k24f2, and the other with normal antigenic characteristics. replication of the antigenic variant ...19911705995
dissociation of alanine aminotransferase values in acute hepatitis a patients with and without past experience to the hepatitis b virus.serological markers and peak serum alanine aminotransferase (alt) values of 140 in-patients with acute hepatitis, either type a (n = 90), or type b (n = 50) were prospectively assessed. in 23 out of the 90 patients with acute hepatitis a, evidence of previous experience with hepatitis b virus (hbv) was found, whereas 35 out of the 50 patients with acute hepatitis b had past contact with hepatitis a virus (hav). the mean peak alt values [s.d.] were significantly higher in hepatitis a patients wit ...19912019305
[the modulation of the interferon system by gamma-globulin preparations].preparations of specific and commercial gamma-globulin against hepatitis a virus caused a marked inhibition of alpha- and gamma-links of the if system 7 days after administration. in 80% of the subjects given commercial gamma-globulin 14 days after administration the above values returned to those observed before administration of the preparations. the recovery of the leukocyte capacity for alpha-if production after administration of specific gamma-globulin was observed only in 50% of the subjec ...19911713374
prophylactic treatment regimens for the prevention of hepatitis a. current concepts.hepatitis a virus (hav) occurs worldwide. in developing countries the virus is endemic, with the majority of the population being exposed to it in childhood, when the infection usually causes, at the most, a mild anicteric illness. in developed countries the majority of hav infections occur at a later age, often in adults, especially those with a history of recent travel to developing countries. in adults, hav infection usually causes a symptomatic icteric illness. in addition to community sanit ...19911715265
changing epidemiology of hepatitis a virus (hav) infection: a comparative seroepidemiological study (1979 vs 1989) in north-east italy.a comparative seroepidemiological study (1979 vs 1989) on hav infection, was carried out in children and adolescents from north-east italy. anti-hav was tested in 850 subjects 6 to 8 years of age and the results were compared to those observed in 1979, in 462 subjects of the same age range and from the same geographical area. overall anti-hav prevalence was 1.9% (ranging from 0.5 to 5.2) in 1989 vs 32.5% (ranging from 7.8 to 70.7) in 1979. this dramatic decline of hav infection in children and a ...19911742523
severe herpes simplex virus hepatitis following autologous bone marrow transplantation: successful treatment with high dose intravenous acyclovir.a 17-year-old male patient with t-cell type lymphoblastic lymphoma in complete remission underwent high dose chemotherapy (busulfan 16 mg/kg and cyclophosphamide 120 mg/kg) followed by autologous bone marrow transplantation (abmt). the patient had been taking oral acyclovir (200 mg x 5) daily from seven days prior to the abmt (day -7). on day +24, he complained of epigastralgia and general malaise, and the next day his got and gpt rose to 570 u/l and 397 u/l, respectively. although he had no muc ...19911753418
hepatitis a virus infection in taipei city in 1989.to evaluate the current status of hepatitis a virus (hav) infection, a seroepidemiologic study to detect the prevalence of antibodies against hav (anti-hav) has conducted in taipei city, from march to july, 1989. serum specimens were collected from 602 male and 503 female apparently healthy children age 12 and under. the prevalence rate of anti-hav was 27.5% in infants, and decreased to nearly 0% in preschool and early school children up to 10 years old. compared to a previous study in the same ...19911678406
adsorption-elution with negatively and positively-charged glass powder for the concentration of hepatitis a virus from water.two methods based on virus adsorption and elution from glass powder were developed for the concentration of hepatitis a virus (hav) from large volumes of water. the cytopathogenic phm-175 strain of hav was used to test these procedures in tap water, fresh water, sea water and raw sewage. hav was quantitated by a plaque assay in the frhk-4 cell line. hav was concentrated by glass powder adsorption-elution from 20-liter samples with satisfactory efficiencies in all types of water: 100% for tap wat ...19911650787
the hepatitis a virus polyprotein expressed by a recombinant vaccinia virus undergoes proteolytic processing and assembly into viruslike particles.hepatitis a virus (hav) contains a single-stranded, plus-sense rna genome with a single long open reading frame encoding a polyprotein of approximately 250 kda. viral structural proteins are generated by posttranslational proteolytic processing of this polyprotein. we constructed recombinant vaccinia viruses which expressed the hav polyprotein (rv-orf) and the p1 structural region (rv-p1). rv-orf-infected cell lysates demonstrated that the polyprotein was cleaved into immunoreactive 29- and 33-k ...19911651421
[the adaptation of an isolate of the hepatitis a virus to reproduction in cell cultures].a hav strain derived from a patient in moscow multiplied in a continuous cell line plc/prf/5 at 32 degrees c (variant mi-1) and at 37 degrees c (variant mi-1.1). these two variants of the strain mi retained the ability for reproduction both at 32 degrees c and 37 degrees c after passages in cell culture. the strain mi also replicates in mk cells. negative results on hav cultivation were obtained in hef-240 and frhk-4 cell cultures. the mi-1 and mi-1.1 variants are typical of hepatitis a viruses ...19911652866
protease digestion of hepatitis a virus: disparate effects on capsid proteins, antigenicity, and infectivity.high concentrations of either trypsin or chymotrypsin caused nearly complete cleavage of capsid protein vp2 of hepatitis a virus but did not significantly reduce the infectivity, thermostability, or antigenicity of the virus. chymotrypsin also had a lesser effect on vp1. these findings indicate the presence of a protease-accessible vp2 surface site which neither contributes significantly to the dominant antigenic site nor plays a role in the attachment of the virus to putative cell receptors.19911654460
decrease of hepatitis a and b virus infections in the population of okinawa, japan.in 1988 1282 serum samples were collected from healthy japanese persons living on hateruma island (574 samples) and iriomote island (708 samples) in okinawa, japan. serological markers of hepatitis b virus (hbv) infection [hepatitis b surface antigen (hbsag), antibody to hepatitis b core antigen (anti-hbc) were investigated and the findings compared with samples taken in 1980 on hateruma island and in 1970 and 1980 on iriomote island. the samples collected in 1988 on iriomote island were also te ...19911753133
characterization of hepatitis a virus capsid proteins with antisera raised to recombinant antigens.the capsid proteins of hepatitis a virus (hav) were expressed as fusion proteins of beta-galactosidase in e. coli using the expression vector lambda gt11. four fusion proteins were stably expressed and used to immunize rabbits to obtain mono-specific antisera. the antisera were unable to neutralize viral infectivity or react with hav by radioimmunoassay. three of the antisera were able to recognize hav antigens in infected bs-c-1 cells by immunofluorescence and denatured capsid proteins by immun ...19911651950
[comparative morphology of spontaneous hepatitis a in lower old world monkeys].detailed description of liver damage in two species of macaques (rhesus and fascicularis) and green monkeys with spontaneous hepatitis a (ha) induced by the virus similar to human hepatitis. a virus (hav) is given. evolution of histological changes was followed by serial liver biopsies. the picture of the hepatitis in the above monkey species resemble that of human na as well as ha in other monkey species susceptible to hav. only in 8 of 21 monkeys the disease lasted for 2-5 months, others exhib ...19911793374
[igm- and igg-class antibodies to the hepatitis c virus].the test system widely used currently for the determination of anti-hcv permits the detection of anti-hcv igg alone. the data recently published by t. g. wreghitt et al. confirm the probability of the presence of anti-hcv of both igg and igm classes in sera from hepatitis c patients. anti-hcv igm was detected by ortho test with some modifications using an anti-m conjugate in the last stage of the experiment. anti-hcv igg were detected by regular ortho test. a total of 46 patients with different ...19911796581
the role of secretory immunity in hepatitis a virus infection.because the role of intestinal immunity remains uncertain in hepatitis a, samples of feces and saliva from infected primates and humans were tested for virus neutralizing activity. only two of eight owl monkeys infected by the intragastric route developed neutralizing antibody detectable in extracts of feces collected up to 88 days after viral challenge, although serum neutralizing antibody was present in all monkeys by day 33. similarly, neutralizing antibody was detected in fecal extracts from ...19911845810
the 5' nontranslated region of hepatitis a virus rna: secondary structure and elements required for translation in vitro.although the lengthy 5' nontranslated regions (5'ntrs) of other picornaviral rnas form highly ordered structures with important functions in viral translation, little is known about the 5'ntr of hepatitis a virus (hav). we determined the nearly complete 5'ntr nucleotide sequences of two genetically divergent hav strains (pa21 and cf53) and included these data in a comparative phylogenetic analysis of the hav 5'ntr. we identified covariant nucleotide substitutions predictive of conserved secondar ...19911656072
a high degree of exposure to hepatitis a virus infection in urban children in cameroon.in january 1989, the prevalence of antibodies to hepatitis a virus (anti-hav) was determined by elisa in 702 apparently healthy children 5-14 years old in kumba city, cameroon. children were recruited from those attending six different primary schools, representative of the socio-demographic characteristics of the inhabitants, using a systematic random sampling. the overall igg anti-hav prevalence was 96.9%, reaching 100% by the age of 11 years. in primary school beginners the prevalence was ver ...19911656166
hepatitis a outbreak involving bread.an outbreak of hepatitis a involved more than 50 residents of a group of villages in the late spring and summer of 1989. the only food that was common to all the laboratory-confirmed cases was bread, purchased either unwrapped or as rolls, sandwiches or filled rolls, and supplied either directly from one shop or indirectly through its subsidiary outlets. it was concluded that this bread was the most likely vehicle of transmission of the hepatitis a virus and that the bread was contaminated by so ...19911847105
a simple antigen-reduction assay for the measurement of neutralizing antibodies to hepatitis a virus.a simplified hepatitis a virus (hav) antigen-reduction neutralization assay (havarna) was developed to permit the measurement of biologically active antibodies in recipients of candidate hav vaccines. degrees of neutralization were measured from the reduction in the amount of hav antigen synthesized by 7-10 days after infection of mrc-5 (fetal human diploid lung) cell cultures. sera producing a greater than or equal to 50% reduction in viral infectivity were scored as neutralizing. the assay was ...19911847404
a rapid method for determination of endoproteinase substrate specificity: specificity of the 3c proteinase from hepatitis a virus.the preferred amino acid residues at the p'1 and p'2 positions of peptide substrates of the 3c proteinase from hepatitis a virus (hav-3c) have been determined by a rapid screening method. the enzyme was presented with two separate mixtures of n-terminal acetylated peptides, which were identical in sequence except for the amino acids at the p'1 or p'2 positions, where a set of 15 or 16 amino acids was introduced. enzyme-catalyzed hydrolysis of the peptide mixtures generated free amino termini, wh ...19911662396
detection of hepatitis a virus and other enteroviruses in water by ssrna probes.sensitive and specific methods are needed to detect hepatitis a virus (hav) and other human enteroviruses in environmental samples such as drinking water and foods. clones of cdna encoding the 5'-most 1 kb of the hav and coxsackievirus b3 (cb3) genomes were subcloned into t7/sp6 rna transcription vectors. in vitro transcribed rna from the t7 promoter detected their respective hav or cb3 genomic rna. conversely, sp6 transcripts detected viral negative-stranded rna but not the genome. when both ss ...19911849914
influence of polyions on the early steps of enterovirus infection.the influence of electric charged molecules on the early phases of enterovirus infection was studied in order to select antiviral compounds able to prevent viral attachment. the effect of different polyelectrolytes on the multiplication of coxsackie virus b3, echovirus 6 and hepatitis a virus was investigated in susceptible cells by adding the drug before, during or after the viral adsorption period. among polyanions, the polysaccharides heparin and dextran sulfate inhibited viral infectivity, d ...19911663994
[the results of a controlled field trial of a dried erythrocytic immunoglobulin diagnostic agent for detecting the hepatitis a virus antigen].the results of the controlled field trial of lyophilized erythrocytic immunoglobulin diagnosticum for the detection of hepatitis a virus antigen in the urine and feces of patients are presented. this diagnosticum was used for the study of urine and fecal samples from 225 patients (of these, 176 had hepatitis a) and 54 healthy persons in the passive hemagglutination (pha) test. their blood sera were studied in the pha test (to detect hbsag) and the radioimmunoassay (to detect anti-hav igm). the i ...19911667348
the 5'-terminal nucleotides of hepatitis a virus rna, but not poliovirus rna, are required for infectivity.a series of plasmids containing hepatitis a virus (hav) cdna was constructed such that positive-strand hav rna could be transcribed with t7 rna polymerase. the plasmids differed in the number of 5'-terminal nucleotides representing the junctions between vectors and hav sequences that were present in the transcripts. when these transcripts were used to transfect cultured bs-c-1 cells, it was found that only those transcripts that contained all of the 5'-terminal hav nucleotides, in addition to on ...19911850050
the declining transmission of hepatitis a in thailand.hepatitis a antibody was almost universal among thai children 10-15 years ago. to assess whether transmission of hepatitis a among thai children had declined, contemporary antibody prevalence and seroconversion rates were determined. antibody prevalence in 1987-1988 among children in bangkok declined since 1977 for all ages studied, most markedly among young children. among 453 low-income urban schoolchildren, there were no seroconversions over a 10- to 12-month period (95% confidence interval [ ...19911850444
detection of igm against hepatitis a virus using tissue culture derived antigen.sera from healthy donors and four groups of subjects with acute viral hepatitis were tested for anti-hav igm by elisa with hepatitis a virus antigen grown in tissue culture. the results were compared with those obtained by formalin inactivated hav from 'havab-m' test kit (abbott laboratories, usa). with both preparations of antigens, sera from healthy donors and patients suffering from acute hepatitis b or non-a, non-b did not show anti-hav igm antibodies whereas acute phase sera from hepatitis ...19911850714
translation of hepatitis a virus rna in vitro: aberrant internal initiations influenced by 5' noncoding region.hepatitis a virus (hav) rnas were translated in vitro in rabbit reticulocyte lysates. the pattern of proteins synthesized from full-length hav rna was highly complex, consisting of a continuous spectrum of polypeptides ranging from less than 20,000 to greater than 200,000 da. the pattern was not significantly altered by varying incubation times, ion, or other reaction parameters, or by the addition of hela or bs-c-1 cell extracts to the translation reactions. plasmids engineered with mutations i ...19911850924
autoproteolytic cleavage of recombinant 3c proteinase of hepatitis a virus.a hepatitis a virus cdna fragment coding for the viral proteinase 3c was expressed as a chimeric protein fused in-frame to the c-terminus of beta-galactosidase. following induction of the lac z promoter, polypeptides of 150, 28, 26, and 16 kda, all of which carry 3c antigenicity, were produced. the 28- and 26-kda proteins were identified as autoproteolytic products of the fusion protein by determination of their n-terminal amino acid sequence. the 16-kda protein arises from internal initiation. ...19911850933
in vitro translation of hepatitis a virus subgenomic rna transcripts.a subgenomic cdna clone from hepatitis a virus strain hm175, composed of the last eight nucleotides of the 5' non-translated region and the first 2248 nucleotides of the coding sequence (p1 region), was inserted into a vector under the control of the t7 promoter. restriction enzyme digestion at sites within the structural region and subsequent transcription in vitro yielded rna products which were translated efficiently in rabbit reticulocyte lysates to produce proteins of the predicted sizes. t ...19911851807
an epidemic of hepatitis a attributable to the ingestion of raw clams in shanghai, china.an epidemic of hepatitis a in 1988 in shanghai had an overall attack rate of 4083/100,000 population (292,301 cases). the epidemic curve showed three peaks in january and february. a case-control study of 1208 matched pairs supported that clams were the vehicle for the virus (summary odds ratio, 9.47; p less than .001). analysis of subsets who had eaten clams indicated that only 3.5% with hepatitis a had cooked their clams compared with 18.1% without hepatitis a, and those with the disease consu ...19911658157
prevalence of antibodies to hepatitis c virus in the hemodialysis unit.an enzyme immunoassay was used to detect antibodies to hepatitis c virus (anti-hcv) in 261 patients and 69 staff members of a hemodialysis unit. the prevalence of anti-hcv was 46.7% in patients and 2.9% in staff members (p less than 0.001). the prevalence of anti-hcv increased significantly with increasing duration of hemodialysis (p less than 0.001), but was not related to age, sex, history of blood transfusion, status of hepatitis b or hepatitis a virus infection, or serum alt. patients with h ...19911660221
immunogenicity trial of inactivated hepatitis a virus vaccine in human volunteers.an inactivated hepatitis a virus (hav) vaccine was tested on a group of human adult volunteers. the vaccine was administered subcutaneously, and a control group received a placebo (aluminium hydroxide). the vaccine was found to be relatively well tolerated and non-reactogenic, and levels of anti-hav were comparable to those in other studies.19911663301
identification of hepatitis a virus as a trigger for autoimmune chronic hepatitis type 1 in susceptible individuals.to identify factors contributing to the pathogenesis of autoimmune chronic active hepatitis (cah) healthy relatives of 13 patients with the disorder were followed prospectively for 4 years. 58 relatives were monitored for various serological markers and for t-lymphocyte migration inhibitory activity every 2 months. 3 cases of subclinical acute hepatitis a occurred during the study. in 2 of the 3 subjects, before hepatitis a virus (hav) infection, there was a defect in suppressor-inducer t lympho ...19911673738
[the investigation of anti-hepatitis a virus antibody rate in guangzhou population].the positive rate of anti-hav in 1663 general guangzhou population were investigated by elisa in 1988. the total positive rate of anti-hav antibody ways 65.1%. there are great differences between the overall positive rate of anti-hav antibody and those in different districts and counties. among them, the highest rate was 90.2%, the lowest was 46.7%. the overall positive rate of anti-hav antibody of rural population (79.3%) was significant higher than that of urban population (53.9%). the rates i ...19911664294
genetic variability within the 5' nontranslated region of hepatitis a virus rna. implications for secondary structure and function.the rna genome of hepatitis a virus (hav) contains a lengthy and relatively well conserved 5' nontranslated region (5'ntr). in other picornaviruses, the 5'ntr has been shown to have important functions related to the initiation of viral translation and replication of viral rna, functions which are critically dependent on both primary and secondary rna structure. we have utilized a phylogenetic approach to construct a model of the secondary structure of the hav 5'ntr. by comparing the nucleotide ...19911668324
biological and molecular comparisons of human (hm-175) and simian (agm-27) hepatitis a viruses.comparisons of hm-175, the prototype human strain of hepatitis a virus, and agm-27, a simian isolate, indicate that the two hav viruses differ substantially in sequence and in biological characteristics. the extent of the differences suggests that hepatitis a viruses have a greater potential for diversity than previously assumed.19911668325
demonstration of virus-specific cytotoxic t lymphocytes in liver tissue in hepatitis a--a model for immunopathological reactions.the pathogenetic mechanism leading to liver tissue injury in hepatitis caused by hepatitis a virus is unclear. we have randomly established t cell clones from liver biopsies from 4 patients with hepatitis a. a total of 578 clones was phenotypically analyzed. whereas during the acute phase of disease cd8+ clones dominated over cd4+ clones, from a biopsy taken late after onset of clinical syndromes more cd4+ than cd8+ clones were obtained. interestingly, in a patient with a second exacerbation of ...19911930098
the use of bacteriophages of bacteroides fragilis as indicators of the efficiency of virucidal products.the potential use of bacteriophage b40-8 of bacteroides fragilis for the evaluation of the virucidal activity of antiseptics or disinfectants was investigated. the antiviral activity of two antiseptics and two disinfectants was evaluated according to a standard guideline. the effect of the virucidal agents was assessed on (i) viruses usually spread by direct contact with surfaces with contaminated secretions, i.e. herpes virus 1 and 2, and vaccinia virus, and (ii) viruses transmitted by the feca ...19911936937
demographic features of sporadic acute hepatitis as determined by viral hepatitis markers.the demographic features of acute x sporadic viral hepatitis as diagnosed by specific markers of viral infection in four different cities in north and north-east india, were examined. of 405 patients examined, 26 per cent had hb,ag, 5.9 per cent igm-anti-hav antibody, and 8.4 per cent igm-anti-hbc antibody. hepatitis b occurred more frequently in male patients (76 per cent) compared to hepatitis a (54 per cent), and in the young adult age group (21-30 years), compared to the latter, which occurr ...19911940220
prevalence of the type of hepatitis virus in hospitalized jaundiced individuals.the prevalence of different types of hepatitis virus was estimated in 185 hospitalized jaundiced patients. it was found that 41.08% were positive for hbs ag by elisa method. the jaundiced group was also tested for igm antibody and for total antibodies (igg and igm) to hav infection by elisa method and 5.40% were found to be positive. all patients in the jaundiced group had serum bilirubin above normal values. it was, therefore, assumed that the rest 52.92% were suffering from non a non b virus i ...19911668404
[hepatitis a virus encephalitis]. 19911943302
enteric infections associated with exposure to animals or animal products.the epidemiology and clinical presentation of enteric infections are discussed in this article. these include bacterial, viral, and parasitic illnesses, and are associated with the increasing popularity of drinking unpasteurized milk; eating raw fish and shellfish; consuming undercooked pork, poultry, and eggs; and having contact with pets. salmonella, campylobacter jejuni, vibrio, yersinia, aeromonas, edwardsiella, hepatitis a virus, norwalk virus, anisakis, eustrongylides, diphyllobothrium, na ...19911955706
hepatitis a and b infections in transfusion-dependent thalassaemia from endemic areas.the aim of this study was to determine the prevalence of previous hepatitis a virus (hav) and b virus (hbv) infection which is in 64 transfusion-dependent (td) patients with thalassaemia including 26 patients who were transfused before blood donors were screened for hbv. serial blood samples taken from these 64 patients and 10 non-td beta-thalassaemia intermedia patients during a 3 year period, were tested for antibody to hav (anti-hav), hepatitis b surface antigen (hbsag), antibody to hbsag (an ...19911958422
characterization of hbv2-like infections in spain.hepatitis b viral serum markers suggestive of infection by hepatitis b virus type 2 were found in 354 patients tested in the laboratory during a 2.5 year period of study. confirmation of the hbsag reactivity by neutralization and subtyping analysis and determination of serum hbv-dna by molecular hybridization were carried out on selected samples from these patients. clinical and epidemiological data were obtained from 234 patients and serological follow-up was done in 70 cases. the results obtai ...19911856705
immunologic priming with recombinant hepatitis a virus capsid proteins produced in escherichia coli.hepatitis a virus capsid proteins (vp0, vp3, and vp1) have been synthesized in escherichia coli for use in antigenic and immunogenic analyses. rabbits immunized with each of these individual recombinant capsid proteins developed a rapid neutralizing antibody response when subsequently challenged with a subimmunogenic dose of whole virus.19911850041
hepatitis c virus infection is the major cause of severe liver disease in india.the present study describes the status of hepatitis c virus infection in 167 patients with severe forms of liver diseases in india. the anti-hcv positivity rate was recorded as 43%, 47%, and 42% in patients with fhf, sahf, and cah respectively. hbv and hcv coinfection was recorded in 28% of fhf, 43% of sahf and 75% of the cah cases. superinfection of hcv in hbsag carriers was recorded in the 54% cases of fhf, 60% of sahf and 42% of the cah. none of these 167 patients was positive of hav-igm. fur ...19911909266
detection of anti-hepatitis c virus antibody in fulminant hepatic failure.serial serum samples obtained from 27 patients with fulminant hepatic failure (fhf) in a variety of etiology were tested for anti-hepatitis c virus antibody (anti-hcv) with uses of two different assay systems. the incidence of anti-hcv in patients with fhf due to hepatitis b (ortho test system; 7/11, 63.6%: abbott test system; 9/11, 81.8%) was found to be significantly higher than that in acute hbv hepatitis (ortho test system; 0/17, 0%) (p less than 0.001). in particular, all 3 post-transfusion ...19911909270
urticaria in patients with hepatitis a virus infection. 19911923685
outbreak of acute hepatitis e virus infection among military personnel in northern ethiopia.an outbreak of acute hepatitis e virus (hev) infection occurred from october 1988 to march 1989 in military camps in northern ethiopia. the epidemic was waterborne and entirely confined to military men, of whom 423 hospitalized, icteric patients were studied. the clinical course was mild and short, without any fulminant hepatitis or death. all sera tested for anti-hav-igm were negative and among 54 (13%) patients who were positive for hbsag, 7 (2%) were positive for anti-hbc igm. on the other ha ...19911940876
[isolation of hepatitis a virus in tissue culture. preliminary report]. 19919768193
[igm leptospira antibodies in acute infectious hepatitis cases in children].50 children under the age of 15 years were studied who had been hospitalized in two hospitals in the dominican republic with hiv diagnosed by the presence of biphasic hyperbilirubinemia and elevation of glutamic-pyruvic and glutamic-oxalacetic transaminases. the sera of the patients were examined for the presence of leptospirotic immunoglobulin m (igm) antibodies by means of the enzymatic immunoassay method (ureasa-elisa). the leptospira-positive sera were also investigated for the presence of ...199112290551
peptoids: a modular approach to drug discovery.peptoids, oligomers of n-substituted glycines, are described as a motif for the generation of chemically diverse libraries of novel molecules. ramachandran-type plots were calculated and indicate a greater diversity of conformational states available for peptoids than for peptides. the monomers incorporate t-butyl-based side-chain and 9-fluorenylmethoxy-carbonyl alpha-amine protection. the controlled oligomerization of the peptoid monomers was performed manually and robotically with in situ acti ...19921409642
serum adenosine deaminase in the early diagnosis of typhoid fever.to study the usefulness of the enzyme adenosine deaminase for the early diagnosis of typhoid fever, its activity in serum was assayed in 277 children admitted to the hospital guillermo grant benavente at concepción, chile, from march, 1988, to december, 1990. the children were distributed into seven groups: control, n = 82; bacteremia, n = 8; acute viral respiratory infection, n = 43; febrile children with miscellaneous etiologies, n = 49; pulmonary tuberculosis, n = 3; hepatitis a virus infecti ...19921408480
[hepatitis serology: use and interpretation].presently five viruses causing hepatitis are known, the hepatitis viruses a (hav), b (hbv), c (hcv), d (hdv) and e (hev). the genomic structure is known of most of all these viruses as well as some of their structural and regulatory gene products. using radio- and enzyme immunoassays viral antigens can be detected for hbv and hdv as well as specific antibodies against all the five viruses. the results of these tests are the basis for the diagnosis and the follow-up of these infections but differ ...19921377839
[acute viral hepatitis a and c: report of a case].we present a case of acute hepatitis by simultaneous a and c virus infection. the coinfection was suspected due to the high levels of transaminases lasting more than 9 months after onset of the illness. during the early stages of the illness, the patient had igm antibodies to hepatitis a virus. serological tests for hepatitis b and c viruses, cytomegalovirus and epstein-bar virus were negative. due to the persistently high transaminase levels, we repeated the serology, detecting positive results ...19921389547
epidemiology of hepatitis a: seroepidemiology and risk groups in the usa.surveillance and seroepidemiological data are important in determining optimal hepatitis a vaccine strategies. in the usa, after a decade of declining rates, reported hepatitis a rates gradually increased from 9.2 cases per 100,000 population in 1983 to a peak of 14.4 per 100,000 in 1989. in 1991, 23,144 cases were reported, for a rate of 9.1 per 100,000. since 1983, rates in males have been consistently 20% higher than in females. rates in children, adolescents and adults up to 39 years old hav ...19921476001
nosography and immunopathogenesis of viral hepatitis.five viruses are responsible for the vast majority of cases of viral related hepatitis. they have been named hepatitis a virus (hav), hepatitis b virus (hbv), hepatitis c virus (hcv), hepatitis d virus (hdv), hepatitis e virus (hev). the more recent literature concerning the viral structure, the epidemiology, the serological identification, the clinical course and the prevention of each type of hepatitis is reviewed. hbv is not directly cytopathic. hepatitis is a consequence of the destruction o ...19921501725
sero epidemiological characteristics of hepatitis c encountered in general practice in belgium.a study carried out between 1982 and 1984 established by exclusion diagnosis that 35% of viral hepatitis cases registered in belgium were due to non a, non b (nanb) viruses. recently, a new anti-hepatitis c virus (hcv) detection test was used to analyse the sera of patients in whom nanb hepatitis was diagnosed in that study. using this new serological test for hcv, 29% of the nanb group was found to be positive for anti-hcv. in the 1982-84 study on viral hepatitis diagnosed by general practition ...19921373384
expression of a hepatitis e virus (hev)-trpe fusion protein containing epitopes recognized by antibodies in sera from human cases and experimentally infected primates.a 1700 base cdna fragment coding for the putative structural gene(s) of hepatitis e virus (hev) was inserted into the path 10 expression vector. the fusion protein (c2) expressed by this plasmid was found to contain epitopes recognized by anti-hev antibodies. c2 protein was used in a western blot format to examine its usefulness in detecting anti-hev antibodies in well documented human cases of hev and non-human primates infected with hev. both igm and igg anti-hev could be detected in our weste ...19921373282
[biphasic viral hepatitis "a" associated with autoimmune phenomena].acute hepatitis a virus infection (hav) is a benign, self limited disease with infrequent extrahepatic features unlike the hepatitis b or the nona-nonb virus infection. we describe the case of a 37 year old white woman with hav who had a relapse with a second elevation of the alanine aminotransferase level together with joint pain, skin lesions, angioneurotic edema, and autoantibodies (ana, anti smooth muscle, antiparietal gastric cells). the liver biopsy showed piecemeal and early bridging necr ...19921599770
clinical trial with inactivated hepatitis a vaccine and recommendations for its use.to compare the reactogenicity and immunogenicity of an inactivated hepatitis a vaccine in two different immunisation schedules.19921318765
production of high efficiency of plating hepatitis a virus in primary african green monkey kidney cells.high-titered hepatitis a virus, strain hm-175, was produced in primary african green monkey kidney cells (5.5 x 10(10) tissue culture id50/850 cm2 roller bottle). the virus preparation had an efficiency of plating of 15 particles per infectious unit. single-cycle growth kinetics of the adapted virus indicated that after an eclipse period of 2 days, maximal yields were attained 6 days after infection.19921312726
characterization of a genetic variant of human hepatitis a virus.human isolates of hepatitis a (hav) are a single serotype; however, recent genetic surveys using limited nucleotide sequencing have provided evidence that more than one genotype is responsible for hav infection in different parts of the world (jansen et al. [1990]: proc natl acad sci usa 87:2867-2871; robertson et al. [1991] j infect dis 163:286-292). one of these genotypes was originally isolated from panamanian owl monkeys (strain pa21), but has subsequently been found associated with human ca ...19921316423
inactivated hepatitis a virus vaccines. 19921317341
fibroblast growth factor receptors contain a conserved hav region common to cadherins and influenza strain a hemagglutinins: a role in protein-protein interactions?the first extracellular domain of the cadherins has been shown to exhibit extensive sequence homology with the amino termini of the ha1 chains of influenza strain a hemagglutinins. these regions of homology are known to be functionally important in both the cadherins and the hemagglutinins. the homologous regions harbor the tripeptide hav, which has been identified as being the cadherin cell adhesion recognition sequence. here we report that members of the rapidly expanding family of fibroblast ...19921322849
the detection in urine specimens of igg and igm antibodies to hepatitis a and hepatitis b core antigens.the use of urine as a noninvasive specimen for the diagnosis of hepatitis a (hav) and hepatitis b (hbv) virus infections was investigated. specimens of urine were collected at the same time as blood or saliva specimens, or singly in cases of previously serologically confirmed recent infection. the specimens were tested for igg and igm anti-hav and anti-hbc by immunoglobulin class-specific capture radioimmunoassays (gacria and macria). on the basis of assays on urine specimens it was possible to ...19921474376
fibrin ring granulomas in hepatitis a.fibrin ring granuloma is characterized by a fibrinous ring surrounding a central fat vacuole. it has been found in the liver and bone marrow of patients with q fever, and occasionally with visceral leishmaniasis, cytomegalovirus, epstein-barr virus, staphylococcus epidermidis infections, hodgkin's lymphoma, and hypersensitivity to allopurinol. we describe a case of serologically confirmed viral hepatitis a with this lesion in the liver biopsy. a false positive anti-hepatitis a virus igm result h ...19921473440
immune pathogenesis of hepatitis a.in an effort to elucidate the mechanism of liver damage resulting from hepatitis a virus (hav) infection, we have studied infected skin fibroblasts and autologous lymphocytes from hav patients. we report here that hla-restricted virus-specific t cells play an essential role in hav-related hepatocellular injury.19921450708
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