Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| [an experimental observation on rhesus monkeys continuously inoculated with human hepatitis a virus (hav)]. | 1987 | 2835166 | |
| continuous production of hepatitis a virus in plc/prf/5 cell cultures: use of antigen for serology. | the strain cf53 of hepatitis a virus (hav) previously adapted to growth in plc/prf/5 cells was grown in 175 cm2 flasks, at different passages. after infection, cells were incubated at 32 degrees c in rpmi 1640 medium supplemented with 2.5% foetal calf serum (fcs) for 6-12 months. hav which was released continuously in the culture medium was harvested weekly. hepatitis a virus antigen (haag) and infectious virus production was stable during each passage. the antigen titre, determined by radioimmu ... | 1987 | 2828401 |
| nucleic acid sequence of the vp1 region of attenuated ms-1 hepatitis a virus. | the nucleotide sequence of the vp1 region of marmoset-attenuated hepatitis a virus (hav), ms-1, was determined by incorporative dideoxynucleotide sequencing of the rna obtained from purified, liver-derived virus. comparison of this nucleotide sequence to those of four previously published isolates revealed that one of the isolates, hm-175, which was obtained from australia and passed three times in marmosets, had a 8.5-11% nucleotide variability compared to the remaining four isolates which were ... | 1987 | 2829458 |
| seroepidemiology of hepatitis a virus in japan. | a seroepidemiologic study to detect class-specific antibody against hepatitis a virus (hav) was made with 831 randomly collected sera (415 in 1973 and 416 in 1984) from healthy japanese. competitive-inhibition, igg, iga, and igm anti-hav enzyme-linked immunosorbent assays (elisa) were used. both collections showed a low prevalence of igg anti-hav in young age groups and it increased rapidly at middle age and plateued at greater than or equal to 94% prevalence in the older age groups. however, tw ... | 1987 | 2832647 |
| properties of a hepatitis a virus candidate vaccine strain. | this paper describes the biophysical and biochemical properties as well as electron microscopical studies of a candidate hepatitis a vaccine strain propagated in human fibroblast cells. our results indicated that, in cscl, the density of hepatitis a virus (hav) from cell culture supernatant and of hav extracted from infected cells was influenced by the quantity of lipid material associated with hav. antigenicity of untreated hav, therefore, was detected primarily in low density cscl fractions (1 ... | 1987 | 2821186 |
| biochemically silent posttransfusion non-a, non-b hepatitis interferes with superinfection by hepatitis a virus. | superinfection of a silently non-a, non-b (nanb)-infected chimpanzee with hepatitis a virus (hav) resulted in minimal liver enzyme elevations, lack of detectable hav in stool, and questionable presence of hav antigen in liver biopsy specimens obtained during the expected period of virus replication. our findings indicate that even biochemically silent nanb hepatitis can strongly interfere with infection by at least one other hepatotrophic virus. | 1987 | 2822600 |
| detection of hepatitis a virus by extraction of viral rna and molecular hybridization. | hepatitis a virus (hav) rna was extracted from cell culture, serum, liver, and feces and then detected by molecular hybridization with cloned hav cdna. hybridization was approximately 10-fold more sensitive than immune electron microscopy or radioimmunoassay was and less sensitive than was assays of hav infectivity in primates or in cell culture. as little as 10(3) 50% infective doses of hav, or approximately 0.1 pg of viral rna, was detected by this method. analysis of fecal specimens from an e ... | 1987 | 2822759 |
| expression of hepatitis a virus cdna in escherichia coli: antigenic vp1 recombinant protein. | the genome of hepatitis a virus (hav) was reverse transcribed into cdna and molecularly cloned. cdna clones coding for the capsid protein vp1 that carries the major hav antigen were cloned into the expression vector pur290 and expressed in escherichia coli. the recombinant fusion protein reacted in an immunoblot with rabbit anti-hav serum, suggesting that it possesses hav antigenicity. | 1987 | 2822970 |
| the entire nucleotide sequence of the genome of human hepatitis a virus (isolate mbb). | hepatitis a virus (hav) is an important human pathogen causing hepatitis, with high incidence in developed as well as in developing countries. no vaccines are available. in order to determine the primary structure of the hav genome, we have prepared cdnas from viral rna and cloned these into plasmid pbr322. these clones were used to determine the entire nucleotide sequence of the hav rna by rapid sequencing methods. we have compared this sequence of 7470 bases to known partial sequences, and one ... | 1987 | 2823500 |
| [hepatitis a in macaca fascicularis and m. arctoides infected by the java monkey-55 strain of hepatitis a virus]. | the results are presented dealing with experimental inoculation of m. fascicularis and m. arctoides with a strain of hepatitis a virus (hav), yam-55, isolated from a m. fascicularis with spontaneous hepatitis a, and parallel experiments on inoculation of these monkey species with hav preparations (strain has-15) obtained as a result of the strain propagation in frhk-4 cell culture and with specimens from human hepatitis a patients containing hav particles. the yam-55 strain of hav was found to b ... | 1987 | 2825433 |
| genomic heterogeneity among human and nonhuman strains of hepatitis a virus. | cloned cdna probes derived from the p1 and p2 regions of the genome of hm175 virus, a reference strain of human hepatitis a virus (hav), failed to hybridize under standard stringency criteria with rna from pa21 and pa33 viruses, two epizootiologically related hav strains recovered from naturally infected new world owl monkeys. hybridization of these probes to pa21 rna was only evident under reduced stringency conditions. however, cdna representing the 5' nontranslated region of the hm175 genome ... | 1987 | 2433467 |
| inhibition of in vitro hematopoiesis by hepatitis a virus. | inoculation of human bone marrow with hepatitis a virus (hav) resulted in a dose- and duration-of-incubation-dependent suppression of hematopoietic progenitor (cfu-gm, bfu-e, cfu-mix) growth in vitro. monocytic progenitors appeared to be least affected. while hav inactivation by heat or beta-propiolactone and neutralization by specific antibodies completely abrogated hematopoietic inhibition, depletion of adherent bone marrow cells, and enrichment of progenitors did not alter the pattern of supp ... | 1987 | 2443380 |
| [accumulation of the infectious virus and the viral antigen during the multiplication of the hepatitis a virus in an embryonic kidney cell culture of the rhesus macaque (frhk-4)]. | growth characteristics of the has-15 strain of human hepatitis a virus (hav) in rhesus monkey foetal kidney cell line (frhk-4) are described. the conditions optimal for the accumulation of infectious hav and viral antigen (haag) in the infected cells and tissue culture fluids were studied. the production of infectious hav occurred in the first stage while in the second stage predominantly haag was accumulating intracellularly. serological properties of the cultivated hav proved to be very simila ... | 1987 | 2445108 |
| detection of hepatitis a virus by hybridization with single-stranded rna probes. | an improved method of dot-blot hybridization to detect hepatitis a virus (hav) was developed with single-stranded rna (ssrna) probes. radioactive and nonradioactive ssrna probes were generated by in vitro transcription of hav templates inserted into the plasmid pgem-1. 32p-labeled ssrna probes were at least eightfold more sensitive than the 32p-labeled double-stranded cdna counterparts, whereas biotin-labeled ssrna probes showed a sensitivity comparable with that of the 32p-labeled double-strand ... | 1987 | 2447830 |
| [spontaneous hepatitis a with a fatal outcome in rhesus monkeys]. | this is the first report of virologically verified spontaneous hepatitis a in m. rhesus monkeys with severe involvement of the liver leading to the death of the animals. in 21 out of 23 dead monkeys morphological lesions in the liver have been characterized as acute hepatitis. in 6 (26%) animals no other pathological processes were found. in 15 animals hepatitis was combined with other diseases (dysentery, parasitic infestations, coronavirus infection). antigen of hepatitis a virus was detected ... | 1987 | 2451353 |
| [hepatitis-related viral markers in patients under long-term hemodialysis]. | antibody profiles for hepatitis b virus (hbv), hepatitis a virus (hav), cytomegalovirus (cmv), epstein-barr virus (ebv) and human immunodeficiency virus (hiv) were determined on 55 serum samples collected from patients with chronic renal failure who were on long-term haemodialysis for periods ranging from 8 months to 5 years and 3 months. the exposure rates for hbv, hav, cmv, ebv and hiv were 94.5%, 100%, 94.5%, 94.5% and 0% respectively. among the 7 hbsag carriers, 1 and 3 were positive for e a ... | 1987 | 2452721 |
| fulminant hepatitis in asymptomatic hepatitis b surface antigen carriers in greece. | eleven male fulminant hepatitis (fh) patients (mean age: 47.7 +/- 16 years) positive for hepatitis b surface antigen (hbsag) but negative for igm antibody to hepatitis b core antigen (igm anti-hbc) were admitted consecutively to the athens hospital for infectious diseases between may 1981 and november 1983. because of the absence of igm anti-hbc, determined by an enzyme immunoassay, these patients were considered to be hbsag carriers with a superimposed acute hepatitis. three of the 11 patients ... | 1986 | 3098915 |
| [acute hepatitis in childhood. study of 96 cases and 1-year follow-up]. | authors studied 96 children, 56 boys and 40 girls, aged 1 to 16 years, with acute viral hepatitis. 53 patients were diagnosed of hepatitis a virus (hav) detecting antibodies to hav of the igm class; 11 patients were diagnosed of hepatitis b virus (hbv) detecting serologic markers; 32 patients were diagnosed of non a-non b hepatitis. there were no serologic evidence of infection with cytomegalovirus and epstein-barr virus. they report an analytical and clinical comparative study of acute viral he ... | 1986 | 3103507 |
| the genomic map of hepatitis a virus: an alternate analysis. | recently najarian et al. reported a complete cdna sequence of the genomic rna of hepatitis a virus (hav) and the amino acid sequence inferred from it. as a picornavirus, hav contains a single-stranded plus-sense rna encoding a single 'polyprotein' which is post-translationally cleaved to yield the mature structural and non-structural proteins. in order to identify putative cleavage sites a combined function of predicted secondary structure and hydropathy was calculated by najarian et al. for the ... | 1986 | 2854598 |
| antibody against hepatitis a in saudi arabians and in expatriates from various parts of the world working in saudi arabia. | the age-specific rate of exposure to hepatitis a virus (hav) was studied in 1015 native saudi arabians (504 males, 511 females) from the riyadh area. the relatively high prevalence of antibody to hav (anti-hav) (38.6%) in children between 1 and 4 years of age indicates that infection is acquired early in life in the saudi arabian population. the prevalence of anti-hav was found to increase steadily so that by the age of 30 years 91.0% of saudi arabians have anti-hav. the prevalence in adult saud ... | 1986 | 3009629 |
| hepatitis a virus replication in tamarins and host immune response in relation to pathogenesis of liver cell damage. | hepatitis a virus (hav) shedding in the faeces, appearance of hav-ag (antigen) in the liver, and development of humoral immunity to hav have been studied in experimentally infected tamarins. the appearance of liver damage measured by transaminase elevation and histology, in relation to the above variables, suggests that the virus is not cytopathic and the immune system contributes to the production of liver cell damage. preliminary data suggest that hav replication may occur in the mucosa of the ... | 1986 | 3009699 |
| an inactivated hepatitis a viral vaccine of cell culture origin. | hepatitis a virus (hav) strain cr326, adapted to grow in llc-mk2 cells, was highly purified, inactivated with formalin, adsorbed to alum, and tested for capacity to induce antibody to hav in both mice and marmosets. the minimum dose of hav antigen necessary to produce antibody in 50% of mice was 10 ng. as little as three doses of 1 ng each produced antibody in 50% of marmosets. further, all marmosets with any detectable antibody to hav, as a result of vaccination, were protected against virulent ... | 1986 | 3009703 |
| viral hepatitis markers in patients on haemodialysis in a hyperendemic area. | antibody profiles for cytomegalovirus (cmv), hepatitis a virus (hav), hepatitis b virus (hbv) and the delta-agent were determined on 55 serum samples drawn from 55 saudi patients on maintenance haemodialysis for periods ranging from 1.5 months to 2 years. the exposure rates for cmv, hav, and hbv were 100%, 100%, and 72.7%, respectively. there was no intersex difference in positivity for hbv surface antigen (hbsag), antibody to hbsag (anti-hbs), antibody to hbv core antigen (anti-hbc); 15.4%, 65. ... | 1986 | 3009704 |
| structure of the hepatitis a virion: peptide mapping of the capsid region. | milligram amounts of highly purified hepatitis a virus (hav) were obtained from persistently infected cell cultures. the hav polypeptides were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transferred to nitrocellulose for detection by an enzyme-linked immunotransfer blot procedure. the hav nucleotide-derived amino acid sequence was subjected to computer analysis to identify potential immunogenic regions within the hav capsid polypeptides. synthetic peptides correspo ... | 1986 | 3009847 |
| unusual viral causes of transverse myelitis: hepatitis a virus and cytomegalovirus. | twenty to 40% of cases of acute transverse myelitis are attributed to viral infections, although the specific viral etiology is only rarely identified. we studied two patients with transverse myelitis in association with acute hepatitis a virus (hav) infection and acute primary cytomegalovirus (cmv) infection. this is the first well-documented report of an association between hav infection and transverse myelitis, and only the fourth documented case of transverse myelitis in association with cmv ... | 1986 | 3010183 |
| influence of twenty potentially antiviral substances on in vitro multiplication of hepatitis a virus. | a multiwell tissue culture system was developed to study the influence of various substances on hepatitis a virus (hav) propagation. a panel of 20 substances of different structure types, each with known effect against at least some viruses, was studied at a concentration of 100 microm. three substances showed reproducible inhibition. the strongest inhibitor, arabinosylcytosine, also produced cytotoxic changes in cells down to a concentration of 1 microm, and its effect was considered as nonspec ... | 1986 | 3010855 |
| fecal excretion of greek strains of hepatitis a virus in patients with hepatitis a and in experimentally infected chimpanzees. | the presence of hepatitis a virus (hav) in stool samples was determined in 36 children (mean age, 8.9 years) and 38 adults (mean age, 19.9 years) with acute type a hepatitis. three stool samples, taken on admission and thereafter at three-to-five-day intervals, were collected from each patient. the first day of dark urine was considered to be the onset of illness. molecular hybridization of cloned hav cdna to fecal extracts was used to detect hav rna; radioimmunoassay was used to detect hav anti ... | 1986 | 3014009 |
| molecular cloning of cdna from hepatitis a virus strain hm-175 after multiple passages in vivo and in vitro. | hepatitis a virus (hav) strain hm-175 was passaged six times in marmosets, 59 times in cell culture and purified from infected cell culture supernatant fluid. the viral rna was extracted, copied into cdna and the cdna:rna hybrids were cloned into the psti site of plasmid pbr322. the cdna clones were authenticated by hybridization to rna extracted from hav-infected cells and clones representing the 3' end of the genome were identified using a previously authenticated cdna clone. the clones repres ... | 1986 | 3016162 |
| detection of a genome-linked protein (vpg) of hepatitis a virus and its comparison with other picornaviral vpgs. | the nucleotide sequence corresponding to the p3 region of the hepatitis a virus (hav) polyprotein genome was determined from cloned cdna and translated into an amino acid sequence. comparison of the amino acid sequences of the genome-linked proteins (vpgs) of other picornaviruses with the predicted amino acid sequence of hav was used to locate the primary structure of a putative vpg within the genome of hav. the sequence of hav vpg, like those of other picornaviral vpg molecules, contains a tyro ... | 1986 | 3018280 |
| preliminary characterization of a fast-growing strain of human hepatitis a virus. | a fast-growing strain of human hepatitis a (hha) virus was selected by progressively shortening by the time between serial passages of the isolate in the simian cell line frp/3. the virus so selected infected 90-95% of the cells in 7-10 days, and developed a strong cytopathic effect (cpe). the synthesis of hha-specific antigens and the cpe were neutralized simultaneously by standard anti-hha sera. this fast-growing strain has the characteristics of a picornavirus. | 1986 | 3018450 |
| lack of complement-dependent cytolytic antibodies in hepatitis a virus infection. | sera collected from patients with acute hepatitis a virus (hav) infection and convalescent sera were examined for cytolytic activity against hav-infected human-embryo lung fibroblasts (hav carrier fibroblasts). using the 51chromium release assay, no complement dependent antibody mediated cytolytic activity against hav carrier cells could be detected. in control experiments with identical cell strains, anti-herpes simplex virus (hsv) positive sera and complement caused specific lysis of hsv type ... | 1986 | 3020167 |
| [association of the hepatitis a virus with the membranes of infected cells]. | "light" viral antigen (haag) with buoyant density 1.20 g/cm2 and sedimentation coefficient 92s are accumulated together with mature viral particles in hepatitis a virus (hav) infected frhk-4 cells. this haag is localized predominantly in endoplasmic reticulum fraction of infected cells, while nature virions are localized in cytosol. in contrast to mature virus, "light" haag is sensitive to trypsin digestion and is not able to hybridize with synthetic oligodeoxinucleotide which is complementary t ... | 1986 | 3020806 |
| prevalence of antibodies to enteroviruses and varicella-zoster virus among residents and overseas volunteers at agricultural settlements in israel. | within the framework of a comprehensive study of the correlation between enteric diseases and wastewater utilization in agricultural settlements (kibbutzim) the prevalence of several viral antibodies was examined among kibbutz residents and overseas volunteers. the latter were assumed to be a group highly susceptible to local pathogens. for the purpose of this study the presence of antibodies against eight enteroviruses [coxsackieviruses (cox) types a9, b1, b3, and b4, echoviruses (echo) types 4 ... | 1986 | 3021900 |
| kaposi's sarcoma and htlv-iii: a study in nigerian adult males. | sera from 37 adult nigerian men with kaposi's sarcoma (ks), 30 contemporaneous controls bearing primary cell carcinoma of the liver (pcl), and 150 healthy non-tumour-bearing negative controls were tested for antibody to human t-cell lymphotropic virus type iii/lymphadenopathy associated virus (htlv-iii/lav) by enzyme-linked immunosorbent assays (elisa). certain immunocellular functions were also measured: the chemotactic locomotion of peripheral blood monocytes towards casein, delayed-type cutan ... | 1986 | 3021963 |
| detection of hepatitis a virus in seeded estuarine samples by hybridization with cdna probes. | the development and trials of a nucleic acid hybridization test for the detection of hepatitis a virus (hav) in estuarine samples within 48 h are described. approximately 10(4) physical particles of hav per dot could be detected. test sensitivity was optimized by the consideration of hybridization stringency, 32p energy level, probe concentration, and nucleic acid binding to filters. test specificity was shown by a lack of cross-hybridization with other enteroviruses and unrelated nucleic acids. ... | 1986 | 3022645 |
| propagation of hepatitis a virus in human diploid fibroblast cells. | human hepatitis a virus (hav) was propagated in human diploid fibroblast cultures (2bs cells) in vitro. replication of the virus was followed by immunofluorescent staining (if), indirect elisa, and by immune electron microscopy. when 2bs cells were inoculated with faecal extracts containing hav, synthesis of hepatitis a antigen (haag) could be detected in the cytoplasm by if. its concentration reached a maximum at four weeks post-inoculation. measured by solid-phase indirect elisa, the positive/ ... | 1986 | 2881465 |
| comparison of indirect immunofluorescence and radioimmunoassay for detecting antibodies against hepatitis a virus of the igg and igm classes. | indirect immunofluorescence test (iif) and radioimmunoassay (ria) were compared for determining anti-hepatitis a virus (hav) igg and igm. 142 sera were tested for anti-hav igg and 16 for anti-hav igm, both with iif and ria techniques. the correlation between the results reached 98.6% for anti-hav igg and 93.75% for anti-hav igm detection, confirming the specificity and sensibility of iif. | 1986 | 3034306 |
| relationship of theiler's murine encephalomyelitis viruses to the cardiovirus genus of picornaviruses. | sequence analysis of vp1 in the da strain of theiler's murine encephalomyelitis viruses (tmev) showed that 13 of the first 23 n-terminal amino acids were identical to those in the corresponding protein of encephalomyocarditis virus. there was little similarity to the corresponding vp1 sequences of poliovirus types 1, 2 and 3, coxsackievirus b3, human rhinoviruses 2 and 14, human hepatitis a virus or foot-and-mouth disease virus. these results, as well as serological relationships detected by imm ... | 1986 | 3034822 |
| incidence of hepatitis a virus (hav) infection in rural liberia. | to provide background for future hepatitis a vaccine trials, sera were collected from 0- to 4-year-old liberian infants and their mothers on two occasions an average of 14.75 months apart and tested for antibody to hepatitis a virus (anti-hav). the prevalence of anti-hav rose from 2.5% in infants 0-6 months of age to 70% in children 3-4 years of age and did not differ between male and female infants. the annual incidence of new infections was slightly lower in the first year of life (35%) than i ... | 1985 | 3981150 |
| isolation and propagation of hepatitis a virus in hepatoma cell cultures. | hepatitis a virus (hav) was isolated directly from human faeces in plc/prf/5 cells. in the first passage cell-bound and supernatant viruses were found by immune electron microscopy and by enzymeimmunoassay. serial passaging of hav in plc/prf/5 cells resulted in its adaptation to the cell line and in reduction of the incubation time. hav was still detectable after 10 cell passages. cell-bound as well as supernatant hav were employed as antigens in anti hav igm-enzymeimmunoassay. | 1985 | 2869659 |
| etiopathogenetic aspects of hepatitis a. i. excretion of hepatitis a virus, biochemistry of liver function, and humoral immune response in patients with hepatitis a on admission to hospital. | the excretion of hepatitis a virus (hav) in stools from 30 patients with clinically overt hepatitis a infection on the day of their admission to the hospital was determined and compared with the dynamics and values of biochemical indices of hepatocyte injury as well as with the immune response to hav. virus was found in 16 out of 30 stools (53%) collected within 1 week after the appearance of clinical symptoms. in sera obtained on the day of hospitalization both igm and iga anti-hav were detecte ... | 1985 | 2983007 |
| infectious hepatitis a virus particles produced in cell culture consist of three distinct types with different buoyant densities in cscl. | although hepatitis a virus (hav) released by infected bs-c-1 cells banded predominantly at 1.325 g/cm3 (major component) in cscl, smaller proportions of infectious virions banded at 1.42 g/cm3 (dense hav particles) and at 1.27 g/cm3 (previously unrecognized light hav particles). cdna-rna hybridization confirmed the banding of viral rna at each density, and immune electron microscopy demonstrated apparently complete viral particles in each peak fraction. the ratio of the infectivity (radioimmunof ... | 1985 | 2983123 |
| sequence analysis of hepatitis a virus cdna coding for capsid proteins and rna polymerase. | we report here the nucleotide sequence corresponding to two large regions of the hepatitis a virus (hav) genome. these comprise a sequence of 3274 bases corresponding to the 5' end of the genome, which includes the putative capsid protein region of this picornavirus, and 1590 bases corresponding to the 3' end of the genome, terminating in a 15-base poly(a) tract. these sequences revealed that hav had the characteristic genomic organization of picornaviruses: an open reading frame beginning appro ... | 1985 | 2984684 |
| primary structure and gene organization of human hepatitis a virus. | the rna genome of human hepatitis a virus (hav) was molecularly cloned. recombinant dna clones representing the entire hav rna were used to determine the primary structure of the viral genome. the length of the viral genome is 7478 nucleotides. an open reading frame starting at nucleotide 734 and terminating at nucleotide 7415 encodes a polyprotein of mr 251,940. comparison of the hav nucleotide sequence with that of other picornaviruses has failed to reveal detectable areas of homology. however ... | 1985 | 2986127 |
| [hepatitis a foci in children's collectives studied by using clinico-biochemical, virological and serological diagnostic methods]. | in 4 foci of hepatitis a (ha) at children's institutions in moscow 218 children and 30 staff members were examined. simultaneously with clinico-biochemical studies, specific igm and igg in the blood and hepatitis a virus (hav) antigen in feces were determined by radioimmunoassay. different forms of ha were detected in 29.1% of children in kindergartens, 19.4% of school children and 3.3% of adults, which was due to great differences in the size of the immune stratum among them (igg to hav was det ... | 1985 | 2986394 |
| persistently infected cultures as a source of hepatitis a virus. | primary african green monkey kidney, continuous african green monkey kidney cell line bs-c-1, and buffalo green monkey kidney cultures were infected with a uniform inoculum of hepatitis a virus (hav). although both the cell line bs-c-1 and primary african green monkey kidney cultures produced useful amounts of virus, hav was detected earlier and in greater quantities in primary african green monkey kidney cultures. a persistently infected primary african green monkey kidney culture was developed ... | 1985 | 2988436 |
| a simple method for clonal selection of hepatitis a virus based on recovery of virus from radioimmunofocus overlays. | hepatitis a virus (hav), a non-cytopathic picornavirus, has been quantitated in cell culture by autoradiographic detection of foci of viral replication developing beneath an agarose overlay following fixation and 'staining' of the cell sheet with radiolabelled antibody (radioimmunofocus assay). using a modification of this basic technique, a clonal variant of hm-175 strain hav was isolated from agarose overlying individual radioimmunofoci. virus recovered from the agarose was amplified in small ... | 1985 | 2991315 |
| isolation and immunizations with hepatitis a viral structural proteins: induction of antiprotein, antiviral, and neutralizing responses. | an immune affinity purification procedure for hepatitis a virus (hav) was designed which yielded milligram quantities of the virus with greater than 95% purity. the major structural proteins vp-1, vp-2, and vp-3 were isolated from the purified virus by electroelution from sodium dodecyl sulfate-polyacrylamide gels and used to immunize lewis rats (three to four doses, 10 to 15 micrograms per dose). the two lewis rats immunized with vp-1 developed a strong antibody response to vp-1, as determined ... | 1985 | 2991564 |
| induction of hepatitis a virus-neutralizing antibody by a virus-specific synthetic peptide. | comparative surface feature analyses of the vp1 sequences of hepatitis a virus (hav) and poliovirus type 1 allowed an alignment of the two sequences and an identification of probable hav neutralization antigenic sites. a synthetic peptide containing the hav-specific amino acid sequence of one of these sites induced anti-hav-neutralizing antibodies. it is concluded that a structural homology exists between the two viruses, despite minimal primary sequence conservation. | 1985 | 2991600 |
| [viral hepatitis and aids-associated htlv iii/lav virus infections in drug addicts]. | in 1984 intravenous drug users accounted for 25% of all cases of acute hepatitis b and for 32% of all cases of non-a/non-b hepatitis recorded in the canton of zürich. drug addicts also represented an important risk group for hepatitis a, which occurred in small epidemics. among 141 "healthy" drug users, 10 (7%) individuals showed signs of ongoing hepatitis b virus (hbv-) infection, 26 (19%) individuals had the finding "anti-hbc-alone" (unresolved hbv-infection) and another 69 (49%) individuals w ... | 1985 | 2994210 |
| isolation and adaptation characteristics of hepatitis a virus in primary african green monkey kidney cells: production of antigen useful for elisa serology. | four strains of hepatitis a virus (hav) were isolated from four fecal samples of patients with type a hepatitis by using primary african green monkey kidney (pagmk) cells or frhk-4 cells. in all four samples viral antigen became detectable in pagmk cells at the 3rd passage level after 9 weeks of incubation; detectable levels of antigen were reached earlier in frhk-4 cells. an enzyme-linked immunosorbent assay (elisa) was used to detect hav antigen (hav-ag). blocking experiments with negative and ... | 1985 | 2997078 |
| incomplete neutralization of hepatitis a virus in vitro due to lipid-associated virions. | hepatitis a virus (hav) released from infected bs-c-1 cells was incompletely neutralized when incubated with a variety of convalescent sera (non-neutralizable fraction of 17 to 32%). chloroform extraction of virus resulted in a substantial reduction of the non-neutralizable fraction (to less than 1%), suggesting that non-neutralizable virions might be associated with lipids. non-neutralizable hav recovered from untreated cell culture supernatant fluids sedimented heterogeneously and less rapidly ... | 1985 | 2997380 |
| isolation and molecular cloning of a fast-growing strain of human hepatitis a virus from its double-stranded replicative form. | a fast-growing strain of human hepatitis a virus was selected and characterized. the virus has the unusual property of developing a strong cytopathic effect in tissue culture in 7 to 10 days. sequences of the viral genome were cloned into recombinant plasmids with the double-stranded replicative form as a template for the reverse transcription of cdna. restriction analysis and direct sequencing indicate that this strain is different from that described by ticehurst et al. (proc. natl. acad. sci. ... | 1985 | 2997478 |
| [adaptation to the cell line plc/prf/5 of hepatitis a virus released in the cell culture medium]. | the propagation of hepatitis a virus (hav), cf53 strain, released without any cytopathic effect into the plc/prf/5 cells supernatant, was studied in the course of six serial passages (6th to 11th). the decrease (from 5 to 1 week) of incubation time required to detect hav, by ria, in culture supernatant, the increase in hepatitis a antigen (from 777 to 10,038 c.p.m./50 microliter) and infectivity titre (from 10(3.0) tcid 50/ml to 10(4.5) tcid 50/ml) were consistent with the adaptation of this vir ... | 1985 | 2998570 |
| combined immunoaffinity cdna-rna hybridization assay for detection of hepatitis a virus in clinical specimens. | to apply cdna-rna hybridization methods to the detection of hepatitis a virus (hav) in clinical materials, we developed a two-step method in which a microtiter-based, solid-phase immunoadsorption procedure incorporating a monoclonal anti-hav capture antibody was followed by direct blotting of virus eluates to nitrocellulose and hybridization with 32p-labeled recombinant hav cdna. this immunoaffinity hybridization method is simple and involves few sample manipulations, yet it retains high sensiti ... | 1985 | 2999190 |
| variation among hepatitis a virus strains. i. genomic variation detected by t1 oligonucleotide mapping. | the genomes of eight hepatitis a virus (hav) strains originating from far distant geographic regions such as europe, north africa, middle and north america, australia and the people's republic of china were compared by rnase t1 oligonucleotide mapping. for this purpose, the viruses were propagated in cell cultures and viral rna was isolated from highly purified mature virions. it could be shown that variation in nucleotide sequence is common among hav isolates, but is in the order of magnitude r ... | 1985 | 3002070 |
| localization of hepatitis a virus in marmoset liver tissue during the acute phase of experimental infection. | electron microscopic and virological studies of marmoset liver tissue with acute infection of hepatitis a virus (hav), especially in the earlier stages of infection, were carried out to characterize the maturation process of hav. four marmosets were inoculated intravenously with hav suspension and sacrificed 1 week, 2 weeks, 3 weeks and 4 weeks after inoculation respectively. hepatitis a antigen (haag) in 10% liver homogenates of marmosets was examined by radioimmunoassay and a large amount of h ... | 1985 | 3002896 |
| evaluation of methods for concentrating hepatitis a virus from drinking water. | by using recently developed cultivation and assay systems, currently available methods for concentrating enteric viruses from drinking water by adsorption to and subsequent elution from microporous filters followed by organic flocculation were evaluated for their ability to recover hepatitis a virus (hav). cell culture-adapted hav (strain hm-175) in seeded tapwater was efficiently adsorbed by both electronegative (filterite) and electropositive (virosorb 1mds) filters at ph and ionic conditions ... | 1985 | 3004331 |
| hepatitis a, b and nanb: the viruses and their prevention. | three viruses commonly infect the liver: hepatitis a virus (hav), hepatitis b virus (hbv) and the virus(es) responsible for non a non b hepatitis (nanb). hav infection occurs predominantly by the fecal-oral route and thus is more common in areas where living conditions are poor and personal hygiene suboptimal. immune serum globulin (isg) prevents this form of hepatitis. hbv infection can be spread by either parenteral (e.g. drug abuse) or non-parenteral (e.g. intimate contact) routes. high risk, ... | 1985 | 21279152 |
| monoclonal antibodies to hepatitis a virus. | this paper describes the development of monoclonal antibodies generated against hepatitis a virus (hav). monoclonal antibodies (mcabs) from two murine hybridoma cell lines were found to bind to an epitope recognized in the sera of patients recovering from infection with hav. ascites fluids containing mcabs from one hybridoma (h1 c19) inhibited a maximum of 70% of the 125i-labeled polyclonal human anti-hav from binding to hav-antigen in a competitive radioimmunoassay, indicating that the mcab rec ... | 1984 | 6086829 |
| [effect of the content of hepatitis a antibodies in immunoglobulin preparations on the effectiveness of the immunoglobulin prophylaxis of hepatitis a]. | the results of a strictly controlled experiment showed that prevention of hepatitis a by the injection of immunoglobulin with hepatitis a virus (hav) antibody titer 1:10000 was 3 times as effective as that achieved with immunoglobulin containing hav antibodies in titer 1:2500. it is recommended to determine the level of specific hav antibodies in immunoglobulins and to use immunoglobulins with a high level of hav antibodies for prevention of hepatitis a. | 1984 | 6087581 |
| interference between human hepatitis a virus and an attenuated apathogenic avian virus. | the effect of an attenuated apathogenic avian bursa virus on the course of human hepatitis a viral infection was studied in marmoset monkeys. the monkeys were infected with human hepatitis a virus, then superinfected with avian bursa virus one and three weeks after initial inoculation with human hepatitis a virus. the superinfected monkeys did not show the characteristic serum glutamic pyruvic transaminase (sgpt) elevation. also their liver biopsies showed no pathologic changes. the virus contro ... | 1984 | 6087596 |
| virus-binding activity of fibronectin: masking of hepatitis a virus. | human plasma fibronectin interacts with viruses. when fibronectin-containing human sera negative for antibodies to hepatitis a virus (hav) were added to suspensions of hav, radioimmunological detection of hav was reduced. this masking effect seemed to depend on the fibronectin concentration of the sera: plasma fibronectin purified by cryoprecipitation and affinity chromatography showed a masking effect on purified hav which was dependent on the concentrations of fibronectin and hav. fibronectin ... | 1984 | 6088567 |
| hepatitis a-virus in cell culture. v. neutralizing antibodies against hepatitis a-virus. | a test system for the detection of neutralizing antibodies against hepatitis a-virus (anti-hav-nt) is presented. the anti-hav-nt assay is performed with frhk-4/r cells and the hepatitis a virus (hav) strain gbm/frhk-4/r which has been adapted to these cells. non-neutralized hav is demonstrated 14 days after infection of frhk-4/r cells using a radio-immunoassay for detecting newly grown hav. the influence of differing amounts of hav on the anti-hav-nt titre and the effect of variations in incubat ... | 1984 | 6088963 |
| translation in vitro of hepatitis a virus rna. | rna extracted from highly purified hepatitis a virus (hav) particles was translated in an rna-dependent, cell-free reticulocyte lysate system, and the products were analyzed by sds-polyacrylamide gel electrophoresis and compared with proteins translated from rna of poliovirus. the efficiency of translation in vitro of hav rna was comparable to that of poliovirus rna. processing of the putative precursor molecules of hav proteins, studied in pulse-chase experiments, was impaired when compared wit ... | 1984 | 6089414 |
| diagnosis of hepatitis a infection: comparative specificity of igm capture assays using antigens derived from tissue cultures and marmoset faeces. | hepatitis a virus (hav) antigens from two tissue culture sources were compared with that from the faeces of infected marmosets to determine whether the former were satisfactory substitutes. sera from 313 healthy blood donors and 417 patients with various clinical conditions were tested for igm class antibody to hav (anti-hav igm) using an igm antibody capture assay (macria) with each of the 3 antigens. forty-eight specimens, all from cases of acute hepatitis, were positive in macria with all 3 a ... | 1984 | 6094607 |
| propagation and assay of hepatitis a virus in vitro. | ten strains of hepatitis a virus (hav) originating from far distant geographical locations were adapted to growth in plc/prf/5 (human hepatoma derived and/or mrc-5 (human embryonic lung) cells. in the course of primary adaptation some of these strains exhibited a predilection for distinct cultural conditions such as type of host cell and temperature of incubation. with progressive passage, variant viruses with quite different requirements could be selected; yet, it proved impossible to isolate a ... | 1984 | 6094609 |
| the heat sensitivity of hepatitis a virus determined by a simple tissue culture method. | a method for estimating residual infectious hepatitis a virus (hav) after heat treatment of suspensions of the virus was devised. it made use of a readily maintained cell line (frhk-4) in which the rate of release of hav antigen into the tissue culture medium was directly proportional to the size of the inoculum. loss of viral infectivity after heating could be estimated by inoculating heat-treated hav suspensions into cell monolayers and measuring antigen released from the cultures during 5 wee ... | 1984 | 6094725 |
| stability of hepatitis a virus. | the stabilities of hepatitis a virus (hav) and of poliovirus type 2 were compared under strictly controlled, identical conditions of ph value, temperature, and salt concentration. although the resistance of the viruses proved to be the same from ph 3 to 11, the temperature at which 50% of poliovirus particles became disintegrated during heating at ph 7.0 for 10 min (t50,10 = 43 degrees) differed significantly from that characteristic for hav (t50,10 = 61 degrees). in the presence of 1 m mgcl2, t ... | 1984 | 6096294 |
| hepatitis a virus: growth characteristics of in vivo and in vitro propagated wild and attenuated virus strains. | serial passage of the ms-1 strain hepatitis a virus (hav) in marmosets was shown to increase the yield of virus and to shorten the incubation period from approximately 55 days in the first passage to 3-7 days in the ninth and higher passages. intravenous inoculation of susceptible chimpanzees with ms-1 hav was found to result in a typical course of disease in two animals who had received eighth marmoset-passage virus, including the occurrence of elevated alt activity, presence of hav antigen in ... | 1984 | 6096505 |
| [cloning of hepatitis a virus genomes]. | the hepatitis a virus (hav) belongs to the family of picorna viruses/enteroviridae. its growing pattern in cell cultures deviates from the pattern found in other picorna viruses: hav does not have cytopathic effects and the replication rate of the virus in cell culture is lower than that one of comparable enteroviruses. in order to be able to understand the biochemistry and gene structure of this virus the genomic virus rns was cloned molecularly as cdns and the nucleotid sequence of the genom w ... | 1984 | 6096653 |
| [viruses in the feces of patients with viral hepatitis and other enterovirus infections]. | direct and immune electron microscopy was used to determine the frequency of finding of hepatitis a virus (hav) and other viral agents in feces of patients in relation to the diagnosis and epidemiological situation. hav-containing excretions from patients were analysed ultrastructurally. the highest frequency of hav detection was established in patients in a water-borne and food-borne outbreak of hepatitis a (ha) and was 40.9% and 36.9%, respectively. in patients with ha diagnosis in the period ... | 1984 | 6097043 |
| a microcarrier cell culture system for large scale production of hepatitis a virus. | hepatitis a virus (hav) was isolated from human faeces using a fetal rhesus monkey kidney cell line (frhk-4). infectious medium from passage 12 was used to inoculate a large (5000 cm2) microcarrier cell culture maintained in suspension. the microcarriers used were swollen, collagen-coated dextran beads on which it was easy to propagate frhk-4 cells. intra- and extra-cellular virus levels were assayed and compared with conventional cultures in 25 cm2 plastic flasks. the results show that virus pr ... | 1984 | 6200491 |
| neutralizing monoclonal antibodies to hepatitis a virus: partial localization of a neutralizing antigenic site. | balb/c mice were immunized with purified preparations of hepatitis a virus (hav) isolated after 21 days of growth in llc-mk2 cells. the hav antigen was isolated from cscl gradients and consisted primarily of the following three proteins as analyzed after sodium dodecyl sulfate-polyacrylamide gel electrophoresis and coomassie blue staining: vp-1 at 33,000 daltons, vp-2 at 29,000 to 30,000 daltons, and vp-3 at 27,000 daltons. the spleen cells isolated from two balb/c mice, immunized with two inocu ... | 1984 | 6208377 |
| antibodies directed against human liver specific membrane lipoprotein (lsp) in marmosets experimentally infected with the hepatitis a virus. | autoantibodies directed against liver plasma membrane antigens have recently been described in patients with acute viral hepatitis, type a (avh-a). to further investigate this phenomenon, the antibody against one such liver membrane antigen, liver specific membrane lipoprotein (lsp), was assayed in six marmosets orally inoculated with hepatitis a virus (hav). using a sensitive radioimmunoassay technique, anti-human lsp antibodies were detected in five of six animals. two peaks of 125i-hlsp bindi ... | 1984 | 6705267 |
| acquisition of antibodies to various coxsackie and echo viruses and hepatitis a virus in agricultural communal settlements in israel. | a seroepidemiological study was conducted to measure the antibody prevalence for eight different enteric viruses. these include seven "classical" enteroviruses, ie, coxsackie virus types a9, b1, b3, b4 and three echo virus types 4, 7, and 9, as well as hepatitis a virus (hav), recently classified as enterovirus 72. sera samples were obtained from 791 residents living in 29 agricultural settlements (kibbutzim) with a total population of 15,950. the results indicated that the acquisition of antibo ... | 1984 | 6747611 |
| viral enhancement and interference induced in cell culture by hepatitis a virus: application to quantitative assays for hepatitis a virus. | hepatitis a virus (hav) growing in human diploid lung fibroblast (mrc5) monolayers can either interfere with or enhance the cytopathic effect of newcastle disease virus (ndv) challenge. enhancement of ndv occurred if hav-infected monolayers were challenged with a low multiplicity of infection of ndv and incubated at 35 degrees c. interference occurred if hav-infected monolayers were given a high ndv multiplicity of infection and incubated at 32 degrees c. these phenomena were applied to assays f ... | 1984 | 6320206 |
| a comparison of enzyme-immunoassay and radioimmunoassay for detection of hepatitis a virus and antibodies against hepatitis a virus. | a direct comparison has been made of tracers labelled with an enzyme and with 125i in solid phase enzyme-immunoassay (eia) and solid phase radioimmunoassay (ria) for the detection of hepatitis a virus (hav) antigen and antibodies to hav. by comparing the binding capacity of peroxidase-labelled anti-hav-igg and anti-hav-f(ab)2 fragments tracers, anti-hav-igg was found to have a higher binding capacity than anti-hav-f(ab)2 fragments in both eia and ria. for eia 16.25-fold more anti-hav-igg was nee ... | 1984 | 6321510 |
| persistent infection of human fibroblasts by hepatitis a virus. | infection of human embryo fibroblasts with hepatitis a virus (hav), a picornavirus, leads to an inapparent, persistent infection; cultures can be passed serially with consistent recovery of the virus in the supernatant. all of the cells of a hav carrier culture are infected and proliferate. subcultivation under hav-immune serum cannot achieve a cure or even a reduction in the number of infected cells in hav carrier cultures. no interferon activity can be detected during hav infection and persist ... | 1984 | 6321640 |
| [interference between human hepatitis a virus and an attenuated avian virus non-pathogenic to man]. | 1984 | 6330640 | |
| effect of hepatitis a virus infection on cell metabolism in vitro. | hepatitis a virus (hav), when inoculated into cultures of the plc/prf/5 cell line which produces the surface antigen of hepatitis b virus (hbsag), showed growth characteristics different from those of other picornaviruses. antigen of hav (haag) is expressed only about 10 days after infection. no major impact on the overall macromolecular biosynthesis of the host cells is observed. the growth rate of hav-infected and uninfected cells was comparable, although the plating efficiency of infected cel ... | 1984 | 6364147 |
| present knowledge of viral hepatitis. | the term viral hepatitis refers to the diseases produced by at least three, and perhaps four or five aetiologic agents that differ in their virologic characteristics, ecologic mechanisms, epidemiologic patterns, and long term consequences. these divergences are now well-defined for hepatitis a virus (hav) and hepatitis b virus (hbv). hav is an rna virus dependent upon consecutive transmission in childhood, and is not associated with long term sequelae. in contrast, hbv is a dna virus capable of ... | 1984 | 6429053 |
| aetiology of acute sporadic hepatitis in adults in kenya. | markers for acute hepatitis a virus (hav), hepatitis b virus (hbv), and hepatitis non-a, non-b (hnanb) infections were examined in the sera of 94 patients presenting with acute hepatitis in kenya. hepatitis b virus was responsible for 70% of cases, hnanb for 18%, and hav for only 12%. the use of an igm anti-hbc assay increased the rate of diagnosis of acute hbv infection, thereby reducing the proportion of cases designated as nanb. | 1984 | 6439821 |
| wild malaysian cynomolgus monkeys are exposed to hepatitis a virus. | serum samples were obtained within 3 days of capture from 106 cynomolgus monkeys (macaca fascicularis) in peninsular malaysia. fifty-two monkeys were trapped on the fringes of palm oil estates and 54 in dense primary jungle. sera were tested for antibodies to hepatitis a virus (hav) with a commercial radioimmunoassay. twenty-four animals had detectable serum anti-hav activity (6 of 52 from palm oil estate sites and 18 of 54 from primary jungle sites). among monkeys at both sites, antibody preval ... | 1984 | 6486304 |
| serologic markers of hepatitis b and a infections in the healthy population. | the prevalence of the serologic markers of hepatitis b virus (hbv) and of antibodies to hepatitis a virus (hav) were determined by radioimmunoassay in 200 healthy subjects. one hundred and seven persons (53.5%) were positive for at least one marker of hbv. the prevalence of each marker was: hbsag - 9.0%, anti-hbs alone - 2.0%, anti-hbc alone - 2.5%, anti-hbs and anti-hbc - 29.0%, hbsag and anti-hbc - 11.0%. evidence of a previous infection with hav was found in 155 persons (77.5%); three of them ... | 1983 | 6636535 |
| unrelatedness of factor viii-derived non-a/non-b hepatitis and hepatitis b virus. | a dna hybridization assay was used to detect hepatitis b virus (hbv)-specific dna sequences in extracted sera obtained from chimpanzees infected with hbv, hepatitis a virus (hav), and a factor viii-derived non-a/non-b (nanb) agent. the results did not reveal any hbv-dna homology with sera obtained from animals infected with hav or factor viii-derived nanb. sera obtained from two hbv-infected chimpanzees demonstrated that hbv-specific dna could be detected during the acute phase of the disease. i ... | 1983 | 6403666 |
| evidence for a virus in non-a, non-b hepatitis transmitted via the fecal-oral route. | typical acute hepatitis was reproduced in a human volunteer immune to hepatitis a virus (hav) after oral administration of pooled stool extracts from presumed cases of epidemic non-a, non-b hepatitis. markers of hepatitis b infection, anti-hav igm, and increase in total anti-hav level were not detectable in the volunteer's sera during the course of infection. spherical 27- to 30-nm virus-like particles were visualized by immune electron microscopy (iem) in stool samples collected during preclini ... | 1983 | 6409836 |
| non-a, non-b hepatitis in palermo, western sicily. | aetiological studies were carried out on 407 cases of acute viral hepatitis during two consecutive years in two general hospitals in palermo, sicily. two hundred ninety-seven showed serological evidence of hepatitis a virus (hav) infection and 73 of hepatitis b virus (hbv) infection. of the remaining 37, two had a serologically diagnosed cytomegalovirus hepatitis, while 35 were classified as non-a, non-b (nanb) hepatitis. the frequency of the different major agents of acute viral hepatitis was n ... | 1983 | 6418855 |
| the frequency of hepatitis a and b viruses as the offending viral type in suspected hepatitis. | three hundred and thirty blood samples from patients suspected of having hepatitis on clinical grounds but in whom the aetiology of the hepatitis was unknown (93 whites and 237 blacks) were tested for the presence of hepatitis b surface antigen (hbsag), anti-hbs, total anti-hepatitis a virus (hav) activity and anti-hav of the igm class. these tests identified the offending hepatitis virus whenever this was type a or type b, and also revealed the patient's immune status in respect of these viruse ... | 1983 | 6294888 |
| effect of chlorine treatment on infectivity of hepatitis a virus. | this study examined the effect of chlorine treatment on the infectivity of hepatitis a virus (hav). prodromal chimpanzee feces, shown to induce hepatitis in marmosets (saguinus sp.), was clarified, and the virus was precipitated with 7% polyethylene glycol 6000, harvested, and resuspended. the suspension was layered onto 5 to 30% linear sucrose gradients and centrifuged; the fractions containing hav were dialyzed, and a 1:500,000 dilution of this preparation induced hepatitis and seroconversion ... | 1983 | 6297391 |
| studies in chimpanzees of live, attenuated hepatitis a vaccine candidates. | human hepatitis a virus was attenuated in virulence for chimpanzees by passage in frhk6 and human diploid lung fibroblast cell cultures. a number of variants were developed by passage in cell cultures which showed different levels of virulence/attenuation for chimpanzees. these results were compared to those obtained with marmosets and reported previously. in general, most variants behaved similarly in the two animal types. two chimpanzees which gave vaccine-like responses following inoculation ... | 1983 | 6302710 |
| detection and persistence of specific iga antibodies in serum of patients with hepatitis a by capture radioimmunoassay. | the serum immunoglobulin a (iga) response to hepatitis a virus (hav) was investigated with a sensitive capture radioimmunoassay. in serial serum samples drawn from 15 patients with viral hepatitis a, iga anti-hav antibodies reached their highest titer between 1-2 weeks after onset and peak titers ranged from 10,000-20,000. serum samples were available from six patients 30-32 months after onset of illness. these samples were all positive for iga anti-hav and some had titers similar to peak titers ... | 1983 | 6308139 |
| topology and immunoreactivity of capsid proteins in hepatitis a virus. | hepatitis a virus (hav) was propagated in a hepatoma cell line and complete viral particles with a density of 1.34 g/ml were purified from cell extracts. the topography of the viral proteins (vps) was studied by surface labelling with 125i and a solid-phase oxidant. the order of labelling intensity in complete particles was vp1 much greater than vp3 greater than vp2; labelling of vp4 was undetectable. when the particles were denatured with sodium dodecyl sulfate at 100 degrees c before iodinatio ... | 1983 | 6310355 |
| molecular cloning and characterization of hepatitis a virus cdna. | double-stranded cdna was synthesized from hepatitis a virus (hav) rna and inserted into the pst i site of pbr322. restriction endonuclease digestion and cross-hybridization of fragments yielded a map of overlapping cloned cdnas that included at least 99% of the viral genome. molecular clones containing hav cdna were identified by hybridizing cloned cdna to electrophoretically resolved rna from uninfected and hav-infected tissue culture cells. cloned cdna probes specifically hybridized to rna fro ... | 1983 | 6310601 |
| incidence of hepatitis a virus infection in children in taipei, taiwan. | to understand the prevalence and incidence of hepatitis a virus (hav) infection in chinese children in taiwan, we determined the age-specific prevalence of hepatitis a antibodies (anti-hav) in 823 children, ranging from birth (cord blood) to 19 years of age. the frequency of anti-hav rose with increasing age with three different slopes, probably reflecting different age-specific incidences: lowest under 4 years of age, intermediate between 4 and 10 years, and highest above 10 years. we obtained ... | 1983 | 6313545 |
| posttransfusion hepatitis type a. | hepatitis a virus (hav) transmission through blood is a rare but potential cause of posttransfusion hepatitis. we can now document such a case supported by laboratory evidence of hav in the donor blood. a 10-year-old girl manifested icteric hepatitis a 31 days after receiving a single unit of packed rbcs from a donor who subsequently experienced hepatitis a and died in hepatic failure. hepatitis a virus antigen was detected in the donor's hepatocytes and in plasma obtained from the original dono ... | 1983 | 6313973 |
| [combination of radioimmunological and immunoelectron microscopic methods for detecting hepatitis a virus]. | the possibility of combined performance of radioimmunoassay (ria) and immune electron microscopy (iem) in one preparation using protein a of staphylococcus aureus for hepatitis a virus (hav) detection in fecal specimens from hepatitis a patients within a short time (40-50 min) has been demonstrated. in the examinations of one preparation by ria and iem, their sensitivity was found to be approximately similar. according to ria, a high content of hav antigen was observed in those preparations wher ... | 1983 | 6314673 |
| inactivation of hepatitis a virus and indicator organisms in water by free chlorine residuals. | hepatitis a virus (hav) and selected indicator organisms were mixed together in chlorine-demand-free buffers at ph 6, 8, or 10 and exposed to free chlorine residuals, and the survival kinetics of individual organisms were compared. hav was enumerated by a most-probable-number dilution assay, using plc/prf/5 liver cells for propagation of the virus and radioimmunoassay for its detection. at all ph levels, hav was more sensitive than mycobacterium fortuitum, coliphage v1 (representing a type of ph ... | 1983 | 6314894 |
| enzyme-immunoassay in the diagnosis of human hepatitis a: specific and non-specific reactions. | solid-phase enzyme-immunoassay (eia) used for the detection of hepatitis a virus (hav) often reveals a non-specific activity which can be reduced or fully eliminated in the presence of normal serum. the factor responsible for this activity appeared to be a non-viral eia-active material (nveam) that non-specifically reacted with normal serum of some mammalian species (human, monkey, rabbit, cattle). the hav and nveam have been separated by csc1 gradient centrifugation, where the hav banded in a n ... | 1983 | 6133430 |
| progress toward a live attenuated human hepatitis a virus vaccine. | human hepatitis a virus (hav) was first grown in cell cultures four and one-half years ago, enabling significant progress toward the development of hav vaccines. vaccine development in a number of laboratories has proceeded on three fronts: 1) live, attenuated vaccine of cell culture origin; 2) inactivated vaccine of cell culture origin; and 3) genetic recombinant vaccines. our studies to date have focused most heavily on the development of a live, attenuated hav vaccine, although we have also m ... | 1983 | 6317494 |