Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| neutralizing antibody to hepatitis a virus in immune serum globulin and in the sera of human recipients of immune serum globulin. | we determined the titer of neutralizing antibody to hepatitis a virus in five lots of immune serum globulin and in the sera of human recipients of immune globulin using a new and sensitive procedure, the radioimmunofocus inhibition assay. the neutralizing antibody titer of four immune globulin lots ranged from 1:170,000 to 1:406,000, and was approximately 100-fold the antibody titer determined by radioimmunoassay. the neutralizing antibody titer of a bureau of biologics reference immunoglobulin ... | 1985 | 2991071 |
| 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 |
| detection of hepatitis a virus and antibody by solid-phase radioimmunoassay and enzyme-linked immunosorbent assay with monoclonal antibodies. | monoclonal antibodies (k3-2f2 and k3-4c8) raised against hepatitis a virus were used to develop a solid-phase radioimmunoassay and enzyme-linked immunosorbent assay for the detection of hepatitis a virus and antibody. assays with this pair of monoclonal antibodies were compared in parallel with similarly constructed solid-phase radioimmunoassays and enzyme-linked immunosorbent assays in which human polyclonal serum was used. the monoclonal antibody assay proved to be more sensitive for the detec ... | 1985 | 2991329 |
| 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 |
| hepatitis profile interpretation by microcomputer. | a simple basic computer program for interpreting two serologic markers of hepatitis a virus infection and five serologic markers of hepatitis b virus infection is described. the program is based on a two-dimensional matrix (table) containing all possible combinations of positive and negative test results with their associated interpretations. clinically relevant reports are consistent, reliable, and legible. sample reports are included. | 1985 | 2994456 |
| restrictive events in the replication of hepatitis a virus in vitro. | hepatitis a virus was purified from the feces of 2 patients with unrelated, naturally acquired infections and was inoculated into frhk-4 cells. analysis of protein synthesis by double-label coelectrophoresis and subtraction allowed the resolution of virus-specific proteins synthesized during infection. in frhk-4 cells the two strains of virus studied produced markedly different profiles of virus-specified proteins, with an accumulation of high-molecular-weight proteins for strain hm790 relative ... | 1985 | 2995272 |
| serological diagnosis of acute viral hepatitis. | fifty cases of symptomatic acute viral hepatitis presenting at the washington, d.c., veterans administration medical center between 1976 and 1978 were tested for serological markers of hepatitis virus infection. the etiology of the acute hepatitis appeared to be hepatitis a virus in 20%, hepatitis b virus in 52%, non-a, non-b agents in 22%, delta hepatitis in 4%, and infectious mononucleosis in 2%. the diagnosis of type b hepatitis was difficult to verify because 10% of cases were seronegative f ... | 1985 | 2996863 |
| 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 |
| [spontaneous hepatitis in the crab-eating macaque exposed to immunodepressants]. | a case of spontaneous hepatitis was detected in experiments aimed at working out the conditions for reproduction of the immunosuppressed state in macaca fascicularis with the purpose of subsequent infection of these monkeys with non a non b hepatitis virus transmitted by the fecal-oral route. one of 6 monkeys at the 8th day of the experiment was found to have developed an increase in the level of serum aminotransferases which grew progressively reaching high values by day 14. fecal specimens fro ... | 1985 | 2998096 |
| [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 |
| serum iga anti-hepatitis a virus as detected by enzyme-linked immunosorbent assay. diagnostic significance in patients with acute and protracted hepatitis a. | a capture enzyme-linked immunosorbent assay for the detection of serum iga against hepatitis a virus has been developed. the test was highly specific, and the time course of detectability of iga anti-hav was longer than six months in 42/42 patients with acute or protracted hepatitis a followed prospectively, but shorter than two years in 14/14 patients tested 21-24 months after diagnosis of acute hepatitis a. igm anti-hav were at detectable levels in only 1/42 cases tested six months after the c ... | 1985 | 2998695 |
| 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 |
| igm neutralizing antibody to hepatitis a virus. | 1985 | 2999265 | |
| [isolation of viruses from water using porous silica]. | the possibility of isolation of different viruses, hepatitis a virus among them, from water by means of adsorption chromatography on porous silica was demonstrated. adsorption of viruses on the surface of silica depended on the kind of sorbent, water ph, and the rate of water flow through the column. the maximum elution of the adsorbed virus was observed using buffer solution with ph at least 11.0 and containing 1-2m nacl. these conditions for adsorption-elution were found to be universal for di ... | 1985 | 3000086 |
| [sequence of 3372 rna nucleotide links in the hepatitis a virus coding for capsid vp4-vp1 and nonstructural proteins]. | 1985 | 3000718 | |
| use of immunosorbent electron microscopy for detection of rota- and hepatitis a virus in sucrose solutions. | immunosorbent electron microscopy was used to demonstrate rotavirus in solutions of varying sucrose concentrations after 18, 42 and 66 h of incubation. about 50% of adsorption of virus particles to the grid was achieved after 18 h incubation and nearly 100% after 42 h when compared to trapping of virus from sucrose free solutions. hepatitis a virus was purified in a 10-30% sucrose gradient and each fraction was examined by immunosorbent electron microscopy, direct electron microscopy, immune ele ... | 1985 | 3001117 |
| changing seroepidemiology of hepatitis a virus infection in taiwan. | hepatitis a antibody (anti-hav) in serum was studied from june to october, 1984, by radioimmunoassay in 647 male and 553 female apparently healthy children under 15 years of age in taipei city. the prevalence rate of anti-hav was 27.0% in infants, decreased to around 1% during the preschool age, then increased and remained around 5% until 11-12 years of age, when another increase was noted, and reached 13.6% among the early teenagers. the age-specific prevalence of anti-hav increased with age bu ... | 1985 | 3001219 |
| 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 |
| morphological studies on the mechanism of hepatocellular injury during acute phase of infection in marmosets inoculated with hepatitis a virus. | the histological changes during the acute phase of infection in the livers of marmosets inoculated with hepatitis a virus were examined. the acute phase was divided into four stages according to the liver enzyme changes and serological markers for the viral infection (stage i, ii, iii, iv). round cell infiltration in the portal tracts was first recognized in stage i. localization of parenchymal changes was predominantly periportal in stage i, ii, and iv, whereas the lesion was diffuse in stage i ... | 1985 | 3004101 |
| prevalence of hepatitis a virus antibody among navajo school children. | previous studies of the prevalence of immunity to hepatitis a (anti-hav) in the united states have used urban settings or institutions for the mentally handicapped. in a rural setting among normal children, a serologic investigation of prevalence of anti-hav was conducted in a boarding school adjacent to the navajo reservation. the results show rates of anti-hav that are the highest reported at the ages tested in any subpopulation in the united states, comparable only with those in developing co ... | 1986 | 3004239 |
| 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 |
| preparation of a prototype inactivated hepatitis a virus vaccine from infected cell cultures. | studies were conducted on the preparation, inactivation, safety, and immunogenicity of a prototype hepatitis a virus vaccine prepared from infected cell cultures. bs-c-1 cells maintained in medium 199 without serum were infected with the hm175 strain of hepatitis a virus and harvested after 21-28 days. the harvested virus preparation contained 6.8-7.4 (log 10) cell culture infectious doses/ml. after exposure to 1:4,000 formalin at 35 c, the infectivity titer decreased 10(6)-fold in 30 hr at an e ... | 1986 | 3005435 |
| [hepatitis a virus infection, an etiologic factor in chronic active diseases of the liver? igm antibody of the hepatitis a virus]. | 1986 | 3005941 | |
| the postnatal decline in antibody to hepatitis a virus. | 1985 | 3006297 | |
| adsorption, purification, and growth characteristics of hepatitis a virus strain has-15 propagated in fetal rhesus monkey kidney cells. | a human fecal isolate of hepatitis a virus strain has-15 was adapted to rapid growth in frhk-4 cells by more than 20 7-day passages. a cell culture-derived inoculum of strain has-15 was used at a multiplicity of infection of 80 radioimmunofocus-forming units per cell, and a one-step growth curve was determined. both intracellular production and supernatant release of infectious virions were evaluated. detection of virus release into the medium directly corresponded to intracellular production of ... | 1986 | 3007565 |
| clinical approach to viral hepatitis in homosexual men. | the prevalence of both hepatitis a and hepatitis b is increased in homosexual men. on an annual basis, 5% to 7% of homosexual men will acquire hepatitis a. risk factors for hav infection include length of homosexual activity, number of sexual contacts, and oral--anal sexual contact. the hbsag carrier rate of homosexual men is 5% to 6%, and another 50% have evidence of previous hbv infection with a positive anti-hbs. hbeag is present in a higher precentage of hbsag-positive homosexual men (38% to ... | 1986 | 3007890 |
| immunoassays for the diagnosis of viral enteric pathogens. | the accurate diagnosis of infectious diseases is important for the optimal management of infected patients as well as for the prevention of disease transmission to susceptible individuals. because viral gastroenteritis constitutes an important cause of morbidity in children living in developed countries and of mortality in children living in developing countries, there has been a great deal of interest in the development of effective methods for the diagnosis and study of this disease. while the ... | 1986 | 3009084 |
| 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 |
| hepatitis a antibody in an isolated amerindian tribe fifty years after exposure. | antibody to hepatitis a in an amerindian tribe was found in everyone over 50 years old but in no one younger. we suggest that the tribe had become infected with hepatitis a virus during the period, about 50 years earlier, when they engaged in raids on luso-brasilian settlers, that the virus failed to persist in the tribe when they withdrew into isolation, and that those who had been infected maintained antibody titers without boosting since that time. | 1986 | 3009702 |
| 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 |
| [indices of collective immunity to the hepatitis a virus in different geographical regions]. | antibodies to hepatitis a virus were determined in the sera of healthy population by enzyme immunoassay techniques. the distribution of antibodies in different age groups was compared, taking into account the proportion of persons with high, moderate and low titers. among the surveyed regions, the highest proportion of nonimmune persons was detected in moscow (45 %) and the lowest proportion, in aralsk (7%) and mongolia (3%). in some regions (moscow, vilnius) the characteristic feature of the im ... | 1986 | 3010605 |
| 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 |
| hepatitis a virus: clones, cultures, and vaccines. | 1986 | 3012783 | |
| non-a, non-b hepatitis: evolving epidemiologic and clinical perspective. | evidence for the existence of human hepatitis agents besides hav and hbv is compelling. transmitted predominantly by transfusion and percutaneous inoculation, the type of nanb hepatitis encountered most frequently is epidemiologically similar to type b hepatitis. nanb hepatitis accounts for more than 90% of tah, but can be transmitted by nonpercutaneous routes as well. approximately 15 to 30% of sporadic hepatitis cases are attributable by serologic exclusion to nanb hepatitis agents, and, in ad ... | 1986 | 3012784 |
| immune thrombocytopenic purpura associated with hepatitis a. | a 23-year-old man developed thrombocytopenic purpura at the end of the second week of the clinical evolution of hepatitis a confirmed by viral markers. the bone marrow of this patient showed megakaryocytic hyperplasia. circulating in his serum immune complexes were demonstrated by solid phase conglutinin enzymo-immunoassay. platelet-reactive serum factors were also detected by an indirect immunofluorescence test using fresh donor platelets as targets. the evolution of both the hepatitis and the ... | 1986 | 3013346 |
| [hepatitis a virus in the feces of patients with hepatitis a]. | 1986 | 3013414 | |
| indirect immunofluorescence assay for the detection of hepatitis a virus-specific serum immunoglobulins. | hepatitis a virus-specific bsc-1 cells were used for the detection of serum immunoglobulins to hepatitis a virus by indirect immunofluorescence. of 150 serum samples tested, specific immunoglobulin m was detected only in patients with serologically confirmed acute hepatitis a, while specific immunoglobulin g was detected in patients with acute or past clinical hepatitis a as well as many patients with no known history of hepatitis. | 1986 | 3013929 |
| 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 |
| hepatitis a virus among natives and expatriates in saudia arabia. | 1986 | 3014060 | |
| [possibilities of enzymo-immunologic determination of hepatitis a virus antigens]. | 1986 | 3015431 | |
| 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 |
| hepatitis a infection in new zealand children. | antibody to hepatitis a virus (anti hav), a marker of past infection, was assayed in 2000 sera collected as part of a national survey in 1978-79. the sera were obtained from children and young people aged 0-21 years, resident in all health districts of new zealand. anti hav was detected in 307 sera, giving an overall prevalence of 15.4%. prevalence increased steadily throughout childhood but more slowly during adolescence. there was no sex differential, the age-standardised rate/100 being 15.5 ( ... | 1986 | 3016619 |
| 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 |
| arthritis, vasculitis, and cryoglobulinemia associated with relapsing hepatitis a virus infection. | hepatitis a virus, unlike hepatitis b virus, has rarely been associated with extrahepatic features. two patients developed relapsing hepatitis a complicated by arthritis in both cases and cutaneous vasculitis in one. both patients had cryoglobulinemia, with cryocrit values of 4.3% and 8.6%. serologic studies showed that the cryoglobulin consisted of polyclonal igm and igg. the washed cryoglobulin was analyzed by sucrose density gradient ultracentrifugation under neutral (ph 7.4) and acidic (ph 2 ... | 1986 | 3021038 |
| antibody to hepatitis a virus after overt and asymptomatic hepatitis a infection. | the titres of antibody to hepatitis a virus (anti-hav) were found to fall rapidly during 3-4 years after hepatitis a and more slowly thereafter, though they never reached undetectable levels in at least 23 years. the levels of anti-hav in convalescents after overt hepatitis a were found to be significantly much higher than in those who had anti-hav as a result of asymptomatic infection. | 1986 | 3021520 |
| new findings in live, attenuated hepatitis a vaccine development. | strain cr326f of hepatitis a virus, derived from a fecal specimen of costa rican patient 033-03, was passed 15 times in fetal rhesus monkey kidney (frhk6) cell cultures plus eight times in human diploid lung (mrc5) cell cultures to yield variant f and 16 times in mrc5 cell cultures to yield variant f'. both variants were purified by limit dilution passages. virulence for marmosets was assessed at six different passage levels, including variants f and f'. there was a gradual loss of virulence wit ... | 1986 | 3021899 |
| 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 |
| [use of protein a for immune electron microscopic demonstration of hepatitis a viruses]. | 1986 | 3022495 | |
| 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 |
| complete nucleotide sequence of wild-type hepatitis a virus: comparison with different strains of hepatitis a virus and other picornaviruses. | the complete nucleotide sequence of wild-type hepatitis a virus (hav) hm-175 was determined. the sequence was compared with that of a cell culture-adapted hav strain (r. najarian, d. caput, w. gee, s.j. potter, a. renard, j. merryweather, g.v. nest, and d. dina, proc. natl. acad. sci. usa 82:2627-2631, 1985). both strains have a genome length of 7,478 nucleotides followed by a poly(a) tail, and both encode a polyprotein of 2,227 amino acids. sequence comparison showed 624 nucleotide differences ... | 1987 | 3023706 |
| characterization of hepatitis a virus structural proteins. | hav particles isolated from infected cells banded at buoyant densities of 1.42, 1.32, and 1.20 g/ml, and distinctive protein patterns were established by gel electrophoresis and reverse phase high performance liquid chromatography. the relatively higher amounts of p30 in particles with lower buoyant densities suggest that this protein is vp0 and is part of the immature picornavirion. the protein elution profiles obtained by hplc were virtually identical for all the hav strains examined but diffe ... | 1986 | 3024410 |
| [silent infection by the hepatitis a virus]. | 1986 | 3024781 | |
| cell-mediated cytotoxicity in hepatitis a virus infection. | we studied cell-mediated cytotoxicity to hepatitis a virus-infected cells in seven patients with acute type a hepatitis and two controls. skin fibroblast cultures obtained from the skin biopsies of seven patients after acute hepatitis a virus infection and from two persons without history of current or past hepatitis a virus infection were inoculated with hepatitis a virus. infection of fibroblast cultures always resulted in an inapparent, persistent infection with production and release of infe ... | 1986 | 3025069 |
| [comparative study of the effectiveness of immunoelectron microscopic methods for detecting rotaviruses and the hepatitis a virus]. | different variants of immune electron microscopy method used for the detection of rotaviruses and hepatitis a virus in specimens from patients were compared. immune electron microscopy using filtration into agar was shown to be the optimal method for diagnosis of such prevalent infections as rotavirus gastroenteritis and viral hepatitis a. | 1986 | 3026094 |
| hepatitis a virus in stool during clinical relapse. | among 256 patients with acute hepatitis a, 17 (6.6%) had a relapse of the disease between 30 and 90 days after the primary episode. we studied 7 of these patients. serologic testing showed mean alanine aminotransferase levels of 1668 iu/l during the acute stage, 107 iu/l during the early convalescence, and 1027 iu/l during the relapse. tests for igm antibody against hepatitis a virus were positive in the 7 patients at the onset of disease, with decreasing levels in 3 of the 4 patients tested dur ... | 1987 | 3026213 |
| strain of hepatitis a virus causing cytopathic effects isolated in a549 cell line. | 1986 | 3026743 | |
| an epidemic of hepatitis a in an institution for young children. | a common-source epidemic of hepatitis a occurred in an athenian institution boarding 38 children (mean age 4.8 years). all children were examined, and blood was drawn from each at the onset of the study and repeatedly during the next three months. only one child (2.6%) was initially immune to hepatitis a virus as a result of prior infection. the attack rate (62.2%) and the ratio of icteric to anicteric cases (1:1.3) were high despite the administration of immunoglobulin (ig). assays for anti-hav ... | 1987 | 3028130 |
| [occurrence of antibodies against hepatitis a virus in general population. comparative study, 1977-1985]. | 1987 | 3029524 | |
| study of the chemical nature of frp/3 cell recognition units for hepatitis a virus. | research has been carried out in order to clarify the chemical nature of cell receptors interacting with a fast growing strain of hepatitis a virus (hav) producing a cytopathic effect on frp/3 cells. cell surface susceptibility to hav attachment has been studied after treatment with enzymes acting on different chemical groupings. results obtained showed a lowering of cell susceptibility to hav infection following the action of phospholipase a2, phospholipase c, trypsin and beta-galactosidase. th ... | 1987 | 3029555 |
| replicative events in hepatitis a virus-infected mrc-5 cells. | replication of hepatitis a virus (hav) in mrc-5 cells was studied under one-step growth conditions. viral replication neither interfered detectably with cellular dna, rna, and protein synthesis, nor could cytopathologic changes be recorded over a prolonged period of incubation. synthesis of mature, infectious hav particles could be detected as early as 2-4 days p.i. and occurred at a maximal rate around 8 days p.i., shortly before infectivity titers reached a plateau. synthesis of total viral rn ... | 1987 | 3029972 |
| [use of natural sorbents for isolating enteroviruses and hepatitis a virus from water samples]. | the data of the study on optimal conditions for the use of a mineral sorbent, bentonite, for isolation of hepatitis a virus and enteroviruses from water bodies are presented. | 1986 | 3029999 |
| [dynamics of the accumulation of virus particles with different physico-chemical properties in frhk-4 cells infected with hepatitis a virus]. | the propagation time-course of hepatitis a virus (hav, strain has-15) in continuous culture of the foetal rhesus monkey kidney cells (frhk-4) was investigated. the hav infectivity and viral rna content in the infected cells reached the maximal level 5-8 days after infection, while accumulation of hepatitis a antigen (haag) continued for 2-3 weeks more. viral particles with the densities 1.27-1.28 g/cm3 and 1.18-1.22 g/cm3 were isolated from the infected cells as well as the mature virions with t ... | 1987 | 3031492 |
| complete nucleotide sequence of an attenuated hepatitis a virus: comparison with wild-type virus. | the complete nucleotide sequence of an attenuated hepatitis a virus, hav hm-175/7 mk-5, was determined from cloned cdna. this virus was derived from wild-type hav hm-175 after 32 passages in african green monkey kidney cells. the resultant cell culture-adapted virus is attenuated for chimpanzees. this virus was passaged an additional three times in monkey kidney cells to obtain sufficient virus for molecular cloning and was designated hm-175/7 mk-5. three overlapping cdna clones were obtained th ... | 1987 | 3031686 |
| [properties of hepatitis a virus particles produced during infection in vitro]. | four types of virus-specific particles with different sedimentation coefficients and buoyant densities in cscl were shown to be accumulated in hepatitis a virus (strain has-15) infected fetal rhesus monkey kidney cells (frhk-4 line). unlike the mature virions (155s, 1.34 g/cm3), cell-associated isosedimenting 92 s-particles (buoyant densities of 1.30 and 1.20 g/cm3) proved to be sensitive to lipase action. particles of all four types were shown to contain similar sets of polypeptides, and, with ... | 1987 | 3033482 |
| [serum antibodies to the hepatitis a virus in persons following a history of the infection]. | enzyme immunoassay was used for titration of serum antibodies in subjects with a history of clinically pronounced or asymptomatic hepatitis a infection. titers of hepatitis a virus antibodies (anti-hav) essentially decreased during 3-4 years after the disease, then the rate of this decrease slowed down and antibody titers stabilized at low levels. after clinically pronounced hepatitis a anti-hav levels were considerably higher than after the asymptomatic form of this infection. | 1987 | 3033953 |
| cellular changes associated with persistent hepatitis a infection in vitro. | the rate of division, morphology and ultrastructure of bsc-1 cells, persistently infected with hepatitis a virus (hav), were compared with uninfected cells for 60 days after splitting of the cells. both control and infected cells showed a biphasic growth pattern marked firstly by increasing cell density and high mitotic rate (exponential phase) and then high constant cell density and little mitosis (stationary phase). immunoperoxidase studies showed that hepatitis a antigen (haag) appeared as cy ... | 1987 | 3034206 |
| primary hepatitis a virus infection in developing countries: decline of maternal antibodies and time of infection. | in developing countries, hav seems to be responsible for a widespread, inapparent and protective infection during early childhood. this report emphasizes early infection and its relationship to protection by passive immunity from maternal antibody in a highly endemic area such as somalia. our result show that hav infection in somalia primarily occurs during the first 4 years of life (4 months to 4 years). cases are infrequent in the first 3 months due to passive immunity secondary to maternal an ... | 1986 | 3034305 |
| 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 |
| demonstration of hepatitis a virus in cell culture by electron microscopy with immunoperoxidase staining. | virus-like particles were demonstrated by electron microscopy in bs-c-1 cells infected with hepatitis a virus (hav). particles were usually enclosed within vesicles and accompanied by myelin-like membranous structures. less often they were seen free in the cytoplasm. they were never observed in the nucleus. by immunoperoxidase staining particles were found to contain hav antigens. these antigens were also found in the membrane of the vesicles surrounding the masses of particles and adjacent part ... | 1987 | 3034945 |
| cytopathology, plaque assay, and heat inactivation of hepatitis a virus strain hm175. | hepatitis a virus (hav) strain hm175 derived after repeated subculture of persistently infected b-sc-1 cells caused a specific cytopathic effect upon acute infection of b-sc-1 cells. the virus formed visible plaques on b-sc-1 cell monolayers after 9 to 14 days of incubation at 34 degrees c, and virus can therefore be titrated by plaque assay. virus could be re-isolated from plaques of infected cells, which allows the clonal isolation of hav variants. the stability of a plaque-purified variant of ... | 1987 | 3035078 |
| development of a plaque assay for a cytopathic, rapidly replicating isolate of hepatitis a virus. | most hepatitis a virus (hav) replication in cell culture has been reported to be nonlytic and relatively slow. a rapidly replicating isolate of strain hm-175 from persistently infected, serially passed cell cultures (phm-175) was found to induce a cytopathic effect. this observation allowed the development of a classic plaque assay for phm-175 in frhk-4 cells. the plaques were neutralized by polyclonal and monoclonal antisera to hav. | 1987 | 3035079 |
| effect of antiviral substances on hepatitis a virus replication in vitro. | the effect of protamine, atropine, selenocystamine, taxifolin, and catechin on the infectivity and antigenicity of the cell culture-adapted hepatitis a virus (hav) strain cf 53 was studied. the toxicity on uninfected plc/prf/5 cells was examined for each antiviral compound by morphological and biochemical methods, in order to determine concentrations without cytotoxic effect. at these concentrations, protamine and taxifolin, added to infected cells for a 15-day period, caused concentration-depen ... | 1987 | 3035080 |
| immunogenicity of a hepatitis a virus vaccine. | hepatitis a virus (hav) strain hav/hfs/gbm was adapted to and grown in human diploid fibroblast cells. the hav was concentrated by ammonium sulphate precipitation and high-speed centrifugation. the virus was inactivated by beta-propiolacton and purified by sedimentation through a 20% solution of sucrose and by cscl gradient centrifugation. the immunogenicity of different preparations was tested in mice, guinea pigs, and goats. the immune response after vaccination was tested by determination of ... | 1987 | 3035082 |
| studies on heat inactivation of hepatitis a virus with special reference to shellfish. part 1. procedures for infection and recovery of virus from laboratory-maintained cockles. | the consumption of bi-valve molluscan shellfish has been associated with outbreaks of viral gastroenteritis and hepatitis a. investigations were undertaken to determine the heat inactivation conditions necessary to render shellfish such as cockles safe for the consumer. conditions for the laboratory maintenance of live cockles are described. in preliminary experiments either poliovirus (10(6) tcid50/ml seawater) or hepatitis a virus (hav) (approx. 10(4) rfu/ml seawater) was introduced into the s ... | 1987 | 3036554 |
| an a-elisa to detect hepatitis a virus in estuarine samples. | an amplified enzyme-linked immunosorbent assay (a-elisa) for detecting and quantifying hepatitis a virus in estuarine water samples is described. the test was five times more sensitive than a standard elisa and at least two times more sensitive than radioimmunoassay. test sensitivity was unaffected by the procedures used to concentrate the virus in estuarine samples or by the presence of humic and tannic acids in test samples. nonspecific reactions were not encountered with a number of enterovir ... | 1987 | 3038016 |
| regenerative activity in acute hepatitis a virus. autoradiographic study after in vitro incorporation of 3h-thymidine. | the in vitro incorporation of 3h-thymidine by liver tissue obtained using needle biopsy from 14 patients with acute hepatitis a virus (ahav) in the fully developed and recovery stage of disease was studied by the autoradiographic technique. marked incorporation in hepatocyte nuclei was observed in the biopsies of patients in the fully developed stage, while incorporation was absent in the recovery stage of the disease. results show that hepatocyte regeneration begins early in the course of ahav ... | 1986 | 3038151 |
| [the use of the molecular hybridization method for detecting the rna of the hepatitis a virus]. | 1987 | 3038490 | |
| detection of hepatitis a virus in the stools of healthy people from endemic areas. | one-hundred-ninety-two stool samples were tested for the presence of human hepatitis a antigen. sixteen of these were also evaluated for the presence of infectious virus. all samples were obtained from young and apparently healthy people from endemic areas for hepatitis a disease. the isolation of the infectious virus from these stools demonstrates clearly the wide diffusion of the virus in these areas, and its transmission by the oral-fecal route. | 1987 | 3038597 |
| effect of glutaraldehyde on the antigenicity and infectivity of hepatitis a virus. | the effect of glutaraldehyde on the antigenicity and infectivity of hepatitis a virus (hav) was examined. the cf 53 strain, adapted to human hepatoma plc/prf/5 cells, was treated with glutaraldehyde using three different concentrations, 0.02, 0.10, and 0.50%, for various periods of time, 3, 10, and 30 min, respectively. after the virucidal assays, glutaraldehyde and hav were separated by gel filtration, then the antigen (radioimmunoassay) titer and the infectivity titer were determined. the grea ... | 1987 | 3038939 |
| [adaptation of hepatitis a virus strain (jam-55) originally pathogenic for monkeys to a cell culture]. | the results of adaptation of hepatitis a viral strain jam-55 to the culture of embryo kidney cells frhk-4 from macaque rhesus are presented. the viral strain was isolated from a m. fascicularis suffering from spontaneous hepatitis. before inoculating the cell culture the virus was passaged twice in the m. arctoides capable of reproducing hepatitis. frhk-4 cell line inoculation by the monkey liver extract, containing the strain hav-yam-55, resulted in isolation of single viral particles of hepati ... | 1987 | 3039362 |
| evidence of hepatitis a infection in immature rhesus monkeys. | forty immature (less than 2 years old) rhesus monkeys (macaca mulatta) with marked increases in aspartate and alanine aminotransferase activities were examined. serological and histopathological evaluations were done to determine if affected animals were infected with hepatitis a virus. although no clinical signs of illness were noted in any of the monkeys, an excellent correlation was found between the increased serum aminotransferase values and seropositivity with the acute phase (igm) havab-m ... | 1987 | 3039712 |
| hepatitis a virus cdna and its rna transcripts are infectious in cell culture. | a full-length cdna copy of an attenuated, cell culture-adapted hepatitis a virus (hav hm-175/7 mk-5) genome was constructed in the psti site of plasmid vector pbr322. transfection of monkey kidney cells with this plasmid failed to induce the production of hepatitis a virus (hav). the hav cdna was excised from pbr322 and inserted, without the oligo(dg) x oligo(dc) tails, into an rna transcription vector to yield plasmid phav/7. transfection of monkey kidney cells with phav/7 dna induced hav infec ... | 1987 | 3041024 |
| prevalence of hepatitis b virus infection among black children in soweto. | roughly 15% of black children in rural areas of southern africa are carriers of the hepatitis b virus. the purpose of the present study was to determine the prevalence of chronic hepatitis b virus infection among urban black children born and growing up in soweto. a total of 2364 children were studied, ranging in age from 3 to 19 years, and of these, 1319 (56%) were girls. the children were drawn from the highest and the lowest socioeconomic classes. serum samples were tested for all hepatitis b ... | 1986 | 3087462 |
| further studies by immunofluorescence of the monoclonal antibodies associated with experimental non-a, non-b hepatitis in chimpanzees and their relation to d hepatitis. | to further investigate the specificity of the monoclonal antibodies (48-1 and s-1) associated with non-a, non-b hepatitis, extensive immunofluorescence studies were performed on liver biopsy specimens from chimpanzees with experimental hepatitis a, b, non-a, non-b or delta, or from normal chimpanzees. both 48-1 and s-1 antibodies reacted in the same manner with liver biopsy specimens from 47 of 50 (94%) chimpanzees with acute or chronic non-a, non-b hepatitis and 15 of 18 (83%) chimpanzees with ... | 1986 | 3098665 |
| 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 |
| epidemic non-a, non-b hepatitis in patients from pakistan. | epidemic non-a, non-b hepatitis was diagnosed in three young pakistani men during a 10-month period at the los angeles county-university of southern california medical center. all three patients had recently visited or lived in karachi, pakistan. none had serologic markers of hepatitis b virus infection or igm antibody (acute-phase) to hepatitis a virus. a liver biopsy from one patient showed marked cholestasis and cholangiolar transformation of hepatocytes, a pattern previously described in pat ... | 1987 | 3099621 |