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[frequency of serum rotavirus antibodies in a sample of a healthy adult and child population (complement fixation with dextran t70 as adjuvant)]. 19826189460
[enteritis infectiosa]. 19826218446
viral gastroenteritis in infants. 19826216241
human rotavirus infection in efate, vanuatu.serum and fecal samples collected from children with gastroenteritis and healthy children and adults living in efate, vanuatu (formerly the new hebrides), were tested for the presence of human rotavirus antigen or antibody by electron microscopy and enzyme-linked immunosorbent assay. virtually every subject was found to have detectable levels of antibody and age-specific studies showed that primary infections occur early in life. human rotavirus was demonstrated to be the cause of an outbreak of ...19826277206
detection of anti-rotavirus antibody-producing cells in paraffin-embedded tissue sections.an assay to detect anti-rotavirus antibody-producing cells was developed in rabbits. sections of alcohol-fixed, paraffin-embedded tissues were used to make an immunofluorescent "sandwich" consisting of specific antibody-producing cells, a concentrated suspension of bovine rotavirus, and rhodamine-conjugated anti-rotavirus serum. rhodamine-stained, anti-rotavirus antibody-producing cells could be simultaneously stained by a fluorescein-conjugated antiserum reactive to rabbit immunoglobulin.19826283961
comparison of an enzyme immunoassay with electron microscopic procedures for detecting rotavirus.the sensitivity and specificity of an enzyme immunoassay (rotazyme), an ongrid immunoelectron microscopy procedure, and conventional negative stain electron microscopic techniques were compared. by using partially purified human rotavirus and simian rotavirus (sa-11) of known particle concentration, the enzyme immunoassay was essentially equivalent to the immunoelectron microscopic procedure and significantly more sensitive than conventional electron microscopic techniques. the level of sensitiv ...19826284793
incidence of rotavirus in artificially reared pigs and some effects of diarrhoea on the physiology and histology of the gastrointestinal tract.pigs reared on a milk substitute from two days old often developed diarrhoea, but suckled littermates remained healthy. only in a few pigs was diarrhoea associated with the presence of rotavirus. rotavirus was also present in some healthy pigs, and was associated with a reduction in villus length. pigs with diarrhoea usually had an increased amount of digesta in the stomach and a reduction in lactase activity in the small intestine but villus length was unchanged. there was no evidence of lactos ...19826283612
rapid multiple-determinant enzyme immunoassay for the detection of human rotavirus.enzyme immunoassays (eias) can be used to detect rotavirus antigens accurately in human stool specimens. conventional eia systems require prolonged incubations and multiple washing steps, thus making them impractical for truly rapid diagnosis. however, more rapid solid-phase eia systems can be devised which make use of simultaneous binding of enzyme-labeled and solid-phase antibodies at immunologically distinct antigenic sites. a multiple-determinant eia system was devised that was capable of de ...19826282992
diarrhoea in dairy calves reduced by feeding colostrum from cows vaccinated with rotavirus.forty-two dairy calves remained with their dams for two days after birth, and then were removed to a calf rearing shed. calves were allocated to three groups for the next 14 days, and received twice daily either whole milk, whole milk with a 10 per cent supplement of pooled normal bovine colostrum or whole milk with 10 per cent supplement of colostrum from cows vaccinated with rotavirus. a natural outbreak of diarrhoea occurred, affecting 28 of the 42 calves. feeding immune colostrum delayed the ...19826283613
complement-fixation test for rotavirus detection: comparison and analysis of different methods to reduce anti-complementary activity of some specimens.the complement-fixation test may be used to detect rotaviral antigens directly in clinical specimens. however, a certain number of specimens tested for human rotaviruses by the complement-fixation test show an anti-complementary activity. by comparing eight techniques we analysed this anti-complementary activity and identified the best method for its reduction. pretreatment of clarified supernatant of stool suspensions by some methods resulted in a reduction of anti-complementary activity, witho ...19826282917
epidemiology of diarrhea due to rotavirus on an indian reservation: risk factors in the home environment.analysis of outpatient visits for diarrheal disease at the san carlos apache reservation, arizona, during 1977-1979 revealed a sharp increase in cases of infantile gastroenteritis of unknown etiology in october and november of each year. during the 1980 autumn diarrhea season, 19 patients and 12 control subjects were selected from among outpatients under two years of age and were interviewed and studied for bacterial and viral enteric pathogens. eleven (58%) of 19 patients and two (17%) of 12 co ...19826282985
new prospects for control of virus diarrhoea in children. 19826283077
gene protein products of sa11 simian rotavirus genome.when ma104 cells were infected with sa11 rotavirus, 12 protein classes, absent in mock-infected cells, could be distinguished by polyacrylamide gel electrophoresis. at least two of these proteins were glycosylated, and their synthesis could be blocked with tunicamycin. the oligosaccharides of both glycoproteins were cleaved by endo-beta-n-acetylglucosaminidase h, suggesting that they were residues of the "high-mannose" type. of the 12 viral polypeptides observed in infected cells, 1 was probably ...19826283128
molecular biology of rotaviruses. iii. isolation and characterization of temperature-sensitive mutants of bovine rotavirus.twenty-six temperature-sensitive (ts) mutants of united kingdom tissue culture-adapted bovine rotavirus were isolated and characterized. fourteen of these mutants were determined to be ts both by efficiency of plating and by virus yield at the nonpermissive temperature of 39.5 degrees c as compared with that at the permissive temperature of 32 degrees c. the remaining mutants were only ts by the criterion of efficiency of plating. high-frequency recombination (gene reassortment) was observed whe ...19826283176
rotavirus infections and the sompe syndrome. 19826282990
age-dependent rotavirus-enterocyte interactions. 19826283556
[rotavirus gastroenteritis (clinical course and diagnosis)]. 19826280328
rotavirus and acute diarrhoeal disease in children in a southern indian coastal town.rotavirus was found by electron microscopy in the stools of 70.7% of a representative sample (368) of the 3355 children with acute diarrhoea admitted to hospital over a period of 16 months in calicut on the west coast of india. the prevalence of the virus was high (nearly 100% of cases examined) in the period from november to january and lowest in may just before the onset of the monsoon. prevalence was high (75.1%) in infants aged from 6 to 23 months, but was considerably lower in those under 6 ...19826282478
[isolation of a cytopathogenic rotavirus from calves].a cytopathic rotavirus was isolated from calves with symptoms of diarrhea and underwent 15 passages in bovine embryo kidney cell culture. the specificity of the isolate was confirmed by the neutralization test, immunofluorescence, electron microscopy. the cpe of the isolated in bovine embryo kidney cells was similar to that of the reference strain.19826280392
the role of respiratory syncytial virus and other viral pathogens in acute otitis media.we utilized recently developed enzyme immunoassay techniques to examine the role of selected viruses in the etiology of acute otitis media. viral pathogens were found in middle ear fluids obtained from 13 (24%) of 53 children with acute otitis media; respiratory syncytial virus accounted for ten of the 13 viral agents identified. in addition, respiratory syncytial viral antigen was found in nasopharyngeal washings obtained from 15 of the 53 children. seven of these children had rsv identified as ...19826283052
radioimmunoassay in diagnostic virology. 19826281600
multiple sclerosis. electrofocused "bands" of oligoclonal csf igg do not carry antibody activity against measles, varicella-zoster or rotaviruses.electrofocused serum and cerebrospinal fluid (csf) specimens from patients with multiple sclerosis (ms) were analysed for immunoglobulins (ig) and for antibodies to measles, varicella-zoster and rotaviruses by an imprint immunofixation method. patterns of intrathecally synthesized antibodies to the 3 viruses differed from patterns of oligoclonal igg in the csf. a variable proportion of virus antibody bands (average 19% for measles antibodies, 8% for varicella-zoster antibodies, 31% for rotavirus ...19826281394
structural analysis of electrophoretic variation in the genome profiles of rotavirus field isolates.detailed structural studies were undertaken on five isolates of bovine rotavirus which showed variability in the migration patterns of their genome segments on electrophoresis in polyacrylamide gels. the individual genome segments of each isolate were characterized by partial digestion of terminally radiolabeled rna with a base-specific nuclease. this analysis showed that whereas mobility variations were always associated with detectable changes in nucleotide sequence, sequence changes at least ...19826282750
[detection of rotavirus in hospitalized and ambulatory infants with acute diarrhea in santiago de chile]. 19826284181
porcine pararotavirus: detection, differentiation from rotavirus, and pathogenesis in gnotobiotic pigs.some characteristics of a newly recognized porcine enteric virus are described. tentatively, the virus was referred to as porcine pararotavirus (parv) because it resembled rotaviruses in respect to size, morphology, and tropism for villous enterocytes of the small intestine. however, it was antigenically distinct from porcine, human, and bovine rotaviruses and reoviruses 1, 2, and 3, and the electrophoretic migration pattern of parv double-stranded rna was distinct from the electrophoretic migra ...19826279693
acquisition of serum antibody to norwalk virus and rotavirus and relation to diarrhea in a longitudinal study of young children in rural bangladesh.serum antibodies to norwalk virus and to rotavirus were measured during longitudinal studies of infectious diseases and nutrition in rural bangladesh. initially, the prevalence of antibody to norwalk virus was 7% in children younger than six months and increased to 80% in children two to five years of age. the incidence of titer increases was highest in one- and two-year-olds and in children who had low or undetectable levels of antibody. some norwalk virus infections appeared to result in diarr ...19826279734
rotavirus infection in nigerian infants and young children with gastroenteritis.in a study conducted over a 5-month period (september 1979 to january 1980), rotaviruses were detected by counterimmunoelectrophoresis in the feces of 16 (13.8%) of 116 infants and young children between 1 and 48 months old with acute, sporadic gastroenteritis, at ife, nigeria. the highest frequency of rotavirus infection was found in th 7- to 12-month age-group (18.9%). males constituted 61% of the sample and excreted rotavirus at a significantly higher rate than did females (p less than 0.01). ...19826280506
human rotavirus rna prepared from stool samples by a simple procedure suitable for the determination of electropherotypes. 19826281287
the differentiation of calf rotaviruses by plaque morphology and serum neutralization. 19826281378
rotavirus infection in new zealand.rotavirus infection is commonly found in young infants admitted to hospital with gastroenteritis. an enzyme-linked immunosorbent assay (elisa) for virus diagnosis is described and the results of testing stool specimens from 497 children with gastroenteritis, 192 neonates and 247 asymptomatic six month old infants are presented. rotavirus infection was found in 45 percent of all children with gastroenteritis but only in 4.7 percent of neonates and 2 percent of asymptomatic infants. these results ...19826281699
rotavirus infection in otago: a serological study.a method for measuring rotavirus antibody in human sera has been established using enzyme-linked immunosorbent assay (elisa). a simian strain of rotavirus (sa11) was used as the antigen. serum eluted from dried blood spots on good quality chromatography paper was found suitable for analysis. paired serum samples from children with gastroenteritis have shown a brisk antibody response in association with the presence of rotavirus in the faeces. community studies indicate that although all older ch ...19826281701
rotavirus viral rna electrophoresis in hospitalized infants with diarrhea in santiago, chile.viral rna electrophoresis technique was used to detect rotavirus in 226 children under 2 years of age with acute diarrhea, admitted to the roberto del río hospital in santiago, chile, during the period of june 1979 through may 1980. a group of 50 children included in the aforementioned sample, admitted in winter, was compared with a control group of 25 infants without digestive pathology. in these groups, rotavirus was detected in 20 out of 50 children with diarrhea (40%) but not in the controls ...19826281717
inhibition of rotaviruses by selected antiviral substances: mechanisms of viral inhibition and in vivo activity.several rna virus inhibitors were evaluated against simian (sa11) rotavirus infections in vitro and murine rotavirus gastroenteritis in vivo. test compounds included 1-beta-d-ribofuranosyl-1,2,4-triazole-3-carboxamide (ribavirin), 3-deazaguanine (3-dg), 3-deazauridine, and 9-(s)-(2,3-dihydroxypropyl)adenine [(s)-dhpa]. all drugs inhibited total infectious sa11 virus yields in ma-104 cells. ribavirin, 3-dg, and (s)-dhpa affected [3h]uridine uptake into uninfected ma-104 cells in both the acid-sol ...19826282209
rna of rotavirus: comparison of rnas of human and animal rotaviruses.single-stranded rna (ssrna) was transcribed in vitro from inner-shell particles of human rotavirus strain wa (hrv-wa) and a bovine rotavirus (neonatal calf diarrhea virus [ncdv]) by virion-associated rna polymerase activity. the ssrna product consisted of 11 rna segments which were separated by polyacrylamide gel electrophoresis. in vitro-transcribed 32p-labeled ssrna was used to study the genetic relatedness between rotaviruses by annealing with genomic double-stranded rna (dsrna) of homologous ...19826281481
enteritis in foals induced by rotavirus and enterotoxigenic escherichia coli.colostrum-deprived, colostrum-fed or suckling foals were orally inoculated with foal rotavirus and enterotoxigenic escherichia coli derived from a calf. neither agent given alone caused diarrhoea in foals aged 1 or 2 days, although with rotavirus, 2 of the 3 inoculated foals became depressed 3 days after inoculation and all 3 were excreting rotavirus in the faeces. inoculation of both agents induced diarrhoea in colostrum-deprived, colostrum-fed or suckling foals aged up to 16 days. there was an ...19826282248
[viral diarrhea].viruses are one of the most frequent causes of acute infectious gastroenteritis. thus, rotaviruses are responsible for 40-60%--and in winter sometimes for over 90% - of diarrhoea in infants. these viruses may also cause disease in adults, but small viruses of a size of about 27 nm, such as the norwalk agent, play a much more important role. several other non-cultivable viruses such as adeno-, calici- and astroviruses have been implicated as a cause of infectious diarrhoea. knowledge of rotavirus ...19826281877
[production of monoclonal antibodies against bovine rotavirus]. 19826282403
viral gastroenteritis. 19826281591
field study of coccidial and rotaviral diarrhoea in unweaned piglets.a study of diarrhoea in unweaned piglets was carried out in nine herds, with special reference to the enteropathogenic agents which could be demonstrated. coccidial (isospora suis) and rotaviral infections were both identified, either singly or in combination. more extensive studies of i suis infection were undertaken in two of the herds and it was found that diarrhoea occurred most commonly in five- to 14-day-old piglets. piglets with i suis infection were not necessarily diarrhoeic but grew po ...19826278696
faecal excretion of alpha-1-antitrypsin in acute diarrhoea.high levels of faecal alpha-1-antitrypsin were found in children suffering from acute rotavirus diarrhoea and in children with diarrhoea in whom no microbial pathogen could be established. the results suggest that transient protein-losing enteropathy is common in acute childhood diarrhoea and may influence the outcome of the disease.19826279037
comparison of elisa, space, and electron microscopy for the routine diagnosis of rotavirus infection.previous studies on the serological diagnosis of rotavirus infection have utilised locally produced antibodies. in this study we have compared two commercially produced assays, an elisa (rotazyme, abbott) and a newly developed assay--solid phase aggregation of coupled erythrocytes (space) (wellcome research laboratories), with electron microscopy (em). the space test appeared less sensitive than em. the elisa was shown to be as sensitive as em but more versatile. our experience suggests that the ...19826277995
the relative importance of rotavirus and other pathogens in the etiology of gastroenteritis in trinidadian children.over a 2-year period, 300 infants less than 3 years old with gastroenteritis admitted to hospitals in trinidad were investigated for the presence of certain microorganisms in the feces, along with an equal number of age- and sex-matched controls. rotavirus was detected in 23% of cases and 1% of controls; salmonella in 7% of cases and in 1% of controls; shigella in 4% of cases and in no controls and two serotypes of enteropathogenic e. coli in 7% of cases and in 2% of controls. campylobacter fetu ...19826277207
prevalence of rotavirus antibody in chickens and horses in louisiana, usa. 19826278698
comparison of solid-phase immune electron microscopy, direct electron microscopy and enzyme-linked immunosorbent assay for detection of rotavirus in faecal samples.one hundred and fifteen faecal samples from children with gastroenteritis have been examined by solid-phase immune electron microscopy (spiem), standard direct electron microscopy and enzyme-linked immunosorbent assay (elisa). diluted high-titered anti-(human) rotavirus serum, produced in rabbit by immunization with purified pooled rotaviruses from gastroenteritis patients, was used as antiserum in the immunological tests. the presence of rotavirus was demonstrated in 41 (36%) of the 115 samples ...19826277978
a two-part study of the aetiological role of rotavirus in intussusception.the aetiology of intussusception is ill-defined, with viruses being incriminated as one of many possible aetiological agents. a two-part study was performed by us to investigate the aetiological role of rotavirus in intussusception. retrospective epidemiological data revealed a negative correlation between the incidence of rotaviral gastroenteritis and the incidence of intussusception. a prospective investigation employing electronmicroscopy, enzyme-linked immunosorbent assay (elisa), and immuno ...19826278072
rotavirus infection in a geriatric population.an outbreak of gastroenteritis affected 19 of 34 geriatric patients and four of 23 staff assigned to the ward in a period of 3 1/2 weeks in january 1980. fourteen of the 19 patients with gastroenteritis (17 were tested properly) and four of the ten asymptomatic patients (five asymptomatic patients were not tested) showed evidence of rotavirus infection by virus positivity and/or a significant antibody response to rotavirus. one of the four staff members with gastroenteritis showed serologic evid ...19826277261
an outbreak of gastroenteritis caused by both rotavirus and shigella sonnei in a private school in rio de janeiro.in may 1980 an extensive outbreak of gastroenteritis occurred in a private school in the city of rio de janeiro. examination of faeces and paired sera showed that this outbreak was caused by both rotavirus and a virulent strain of shigella sonnei. in the first 19 stool samples collected seven (37%) had rotavirus only, six (32%) had sh. sonnei only, while four (21%) had both agents. examination of the second and third stool collections revealed only the presence of sh. sonnei. the 18 paired sera ...19826278017
the molecular biology of rotaviruses. ii. identification of the protein-coding assignments of calf rotavirus genome rna species. 19826278745
longitudinal studies of infectious diseases and physical growth of children in rural bangladesh. ii. incidence of diarrhea and association with known pathogens.longitudinal studies were done in two villages rural bangladesh to learn more about the interactions between infectious diseases and the nutritional status of children. diarrheal diseases, identified by surveillance of 197 children aged 2-60 months, were studied for bacterial, viral and parasitic enteropathogens in 1978-1979. the annual incidence of diarrhea was highest in children aged 2-11 months, and declined progressively with age from seven to four episodes per child per year. an enteropath ...19826278925
definition of human rotavirus serotypes by plaque reduction assay.twenty different human rotavirus reassortants were characterized serologically by a plaque reduction assay as belonging to one of three distinct serotypes. fourteen were similar if not identical to our prototype wa strain; two were like the prototype ds-1 strain, and four belonged to a third serotype for which a prototype has not yet been selected. hyperimmune sera raised against the three serotypes were required to distinguish among them, since postinfection sera had lower titers and were more ...19826286487
influence of humidity on rotavirus prevalence among nigerian infants and young children with gastroenteritis.rotaviruses were detected by counterimmunoelectro-osmophoresis in the feces of 16 (13.8%) of 116 infants and young children with gastroenteritis during a 5-month period (september 1979 through january 1980) in ife, nigeria. the rate of rotavirus detection varied inversely with relative humidity and was highest in december (38.5% positive) when the humidity was lower. there was not such a distinct relationship with temperature or vapor pressure; and although the rate of rotavirus detection was hi ...19826279690
pathology of experimental cv777 coronavirus enteritis in piglets. i. histological and histochemical study.sixteen cesarean-derived colostrum-deprived piglets were infected oronasally with cv777 coronavirus on the second or third day of life. two uninfected piglets were controls. they were killed at 96 and 120 hours after birth. after an incubation period of 22 to 36 hours, all principals showed severe diarrhea. the principals were killed between 12 and 120 hours after infection. exfoliation of enterocytes were seen first in the piglet killed 24 hours after infection (two hours after the diarrhea beg ...19826280359
variance in rotavirus infection rates in different urban population groups in south africa.rotavirus infection in black infants contrasts markedly with that of white infants in being much less common and showing no seasonal variation. in this multicentre study in johannesburg, the aetiology of winter infantile gastroenteritis in black, coloured, and white infants was investigated. stools were examined by electron microscopy and also by enzyme-immunoassay to detect subparticular antigen which may be missed by electron microscopy in patients presenting late in the course of the illness. ...19826296311
a follow-up study on bovine rotavirus dissemination among calves of a large dairy herd.rotaviruses had previously been involved in lethal diarrhoea of newborn calves as well as non-lethal diarrhoea in calves aged 6 to 7 weeks in a closed dairy herd comprising 220 heads of cattle. fifty calves born consecutively were thereafter tested at weekly intervals till 8 weeks old for diarrhoea by clinical judgement of their feces and for rotavirus excretion by elisa tests. serum antibodies against rotaviruses were sporadically determined by cf tests. rotavirus was shown to persist in this h ...19826296636
a general strategy for cloning double-stranded rna: nucleotide sequence of the simian-11 rotavirus gene 8.using simian-11 rotavirus rna, a strategy has been developed for the production of full length cloned copies of the genes of double-stranded (dsrna) viruses. genomic rna segments were polyadenylated and reverse transcribed to yield a mixture of full length cdna copies of both possible polarities. the cdnas were annealed, filled in to complete any partial copies, tailed and inserted into the psti site of pbr322 using dg/dc tailing. cloned rotavirus cdna gene copies were assigned to genomic rna se ...19826296764
rotavirus and hemolytic enteropathogenic escherichia coli in weanling diarrhea of pigs.since the turn of the century, escherichia coli has been implicated in the etiology of weanling diarrhea (colibacillosis). however, rotavirus--a virus that destroys enterocytes--has been shown recently to be causally associated with weanling diarrhea of pigs. the role of both rotavirus and hemolytic enteropathogenic e. coli in weanling diarrhea was assessed in this study. pigs from a closed herd were farrowed and weaned by two markedly different systems: an "intensive care sanitary" system and a ...19826296193
detection of a rotavirus-like agent associated with diarrhea in an infant.a rotavirus-like agent was detected in the feces of a child with diarrhea. although morphologically indistinguishable from rotavirus, the agent was serologically distinct, and electrophoresis of its nucleic acid also showed that it was dissimilar.19826296194
isolation of human rotavirus subgroups 1 and 2 in cell culture.one strain of human rotavirus subgroup 1 (kun) and one strain of subgroup 2 (mo) were isolated with the ma104 cell line, a fetal rhesus monkey kidney cell line. their subgroup specificities and rna patterns were identical to those of rotaviruses present in stools before cultivation. distinct cytopathic effects consisting of obscure cell boundaries, cell fusion, cell rounding, cell detachment, and lytic foci were recognized at passage 3 of mo and passage 6 of kun. no differences in cytopathic cha ...19826296195
effect of tunicamycin on rotavirus assembly and infectivity.bovine rotavirus grown in the presence or absence of tunicamycin was analyzed with respect to yield of infectious virus, the ratio of complete to incomplete particles, and polypeptide composition. tunicamycin at a concentration of 1 microgram/ml reduced virus yields by 4 logs and completely prevented the incorporation of [3h]uridine into complete rotavirus particles, as determined by cesium chloride gradient analysis. concomitant with a reduction in complete particles, three rotavirus polypeptid ...19826292451
immunity to rotavirus in conventional neonatal calves.the local and systemic humoral immune responses to rotavirus were studied in six conventional neonatal calves. attenuated bovine rotavirus was administered either orally or directly into an isolated intestinal loop. the parameters monitored were neutralizing rotavirus antibody in serum, immunofluorescent and neutralizing rotavirus antibody in intestinal loop washings, and rotavirus antibody-producing cells in intestinal mucosa. an antibody response was observed in the serum and intestinal secret ...19826296197
electron microscopy of the intestine of gnotobiotic piglets infected with porcine rotavirus. 19826296207
[frequency of enteropathogenic k99+ st+ escherichia coli and rotaviruses in neonatal diarrhea of calves. survey of a veterinarian's clientele in sarthe].a clinical and microbiological study was carried out on 21 diarrhoeic calves less than 20 days old, belonging to 20 different farms in the french department of sarthe. each diarrhoeic calf was compared with a clinically healthy calf of the same age, from the same farm. two visits were made : one during the acute phase of diarrhoea, the other 10 to 15 days later. of the 21 diarrhoeic calves, nine died. on the first visit, rotavirus was found in faeces of 11 diarrhoeic calves and e. coli k99+ st+ ...19826291442
use of transcription probes for genotyping rotavirus reassortants. 19826289518
comparison between viral rna electrophoresis, elisa and complement fixation techniques with electronic microscopy to demonstrate rotavirus. 19826289766
viral diseases: infections of the gastrointestinal tract.in the 1970s investigations generated a remarkable amount of information on the viruses responsible for acute gastroenteritis. the two viruses responsible for most cases occur in epidemiologically distinct clinical forms. although occasionally epidemic, rotavirus infections are usually sporadic and primarily affect infants and young children. this illness is characterized by severe diarrhea commonly lasting five to eight days and frequently associated with upper respiratory tract symptoms, fever ...19826290133
acute viral enteritis and exacerbations of inflammatory bowel disease.in order to determine whether or not acute viral gastroenteritis predisposes to exacerbations of inflammatory bowel disease, patients with crohn's disease and ulcerative colitis were observed longitudinally. assessment of disease activity was correlated with evidence for viral infection by serology and stool antigen testing. disease exacerbations were rarely associated with rotavirus, norwalk agent, or adenovirus infection, primarily because these infection rates were very low. however, the few ...19826290307
three human rotavirus serotypes demonstrated by plaque neutralization of isolated strains.human rotaviruses were isolated directly from stool specimens of gastroenteritis patients in ma-104 cells in the presence of trypsin. for the plaque assay of the isolated strains, the optimal composition of overlay medium was determined. the antigenicity of the isolated strains was investigated by a plaque neutralization method, using antisera prepared against six strains having different electropherotypes of viral rna, and three different neutralization serotypes were demonstrated.19826292112
solid-phase enzyme immunoassay for rotavirus antigen: faecal protease activity as a reason for false-negative results.rabbits and guinea pigs were immunized with purified bovine rotavirus. immunoglobulin g fractions of the resulting antisera were used in a standard four-layer solid-phase enzyme immunoassay (eia) for rotavirus antigen in human faecal specimens. samples negative for rotavirus in electron microscopy, when diluted in standard eia buffers, regularly gave absorbance values lower than those obtained with buffer blank only. by further diluting of the samples the resulting absorbance values were found t ...19826292250
identification of a neutralization-specific antigen of a calf rotavirus.monospecific polyclonal antisera were raised in guinea-pigs against the calf rotavirus polypeptides vp1, vp2, vp3 + 4, vp4.2, vp6, vp7.1, vp7.2 and vp10. all of the antisera gave a similar pattern of cytoplasmic immunofluorescence in rotavirus-infected cells, but spots of fluorescence of varying intensity with different sera were seen over the nucleus. immune precipitation, using staphylococcus aureus to collect immune complexes, showed that vp2 was precipitated by antiserum to vp2 (alpha-vp2) a ...19826292353
in vitro transcription of two human rotaviruses.the rna polymerase activities of a cultivatable (wa) and a noncultivatable (ds-1) strain of human rotavirus were studied. under optimal conditions, transcription of all of their rna segments occurred, as evidenced by the hybridization of labeled transcripts to genomic rna. cross-hybridization between the two viruses showed that none of their 11 genes were completely homologous. the transcription products could be translated in vitro, yielding proteins with an electrophoretic pattern resembling t ...19826292446
purification and characterization of bovine rotavirus cores.using the chaotropic effect generated by a high concentration of cacl2, we converted calf rotavirus particles into cores of 40 nm in diameter. these cores were purified by rate zonal centrifugation in sucrose gradients and by isopycnic gradients. they had a sedimentation coefficient of 280s +/- 20s and a density of 1.44 g/ml in cscl. when analyzed by polyacrylamide gel electrophoresis, they contained three polypeptides (vp125, vp89, and vp78). the major internal polypeptide of the virion (vp39) ...19826292454
enteric viruses of nonhuman primates.the phylogenetic relationship of nonhuman primates to man implies that many of these animals could serve as surrogates for studies of diseases of man. many nonhuman primate species are susceptible not only to viruses of human origin but also to nonhuman primate viruses that are counterparts of viruses of man. all monkeys and great apes do not respond similarly to an antigenic stimulus. some agents are highly pathogenic for one species and completely innocuous for another. for example, poliovirus ...19826293149
serotyping and subgrouping of rotavirus strains by the elisa test.a method is described for the serotyping and subgrouping of rotaviruses by enzyme-linked immuno-sorbent assay (elisa). for the isolates tested "blind" under code in parallel the serotyping results obtained by elisa and serum neutralization of fluorescent focus formation were the same. after absorption of the typing antisera with purified heterotypic rotavirus, up to 128-fold differences in titres between isolates were observed in the elisa test. the results of serotyping and subgrouping, by elis ...19826293413
[experimental studies on the infection of an adult tree shrew (tupaia belangeri yunalis) with human rotavirus]. 19826293669
rotaviral antibodies in cow's milk.in the past, it has been reported that neonatal diets made from unheated cow's milk were superior to those made from heated cow's milk. it was observed that piglets were equally protected from rotaviral diarrhea when they were fed diets made from either unheated milk that came from a cow immunized against porcine rotavirus or from a cow that was not immunized. because of this observation, we examined four pools of "normal" cows' colostrum and 58 samples of "normal" cow's milk for the presence of ...19826293690
molecular biology of rotaviruses. iv. molecular cloning of the bovine rotavirus genome.a new cloning strategy has been developed for cloning the genomes of double-stranded rna viruses by using bovine rotavirus as a test system. the major modification adopted was the use of denatured polyadenylated double-stranded rna as the template for reverse transcriptase. this allowed the two complementary strands of cdna to be synthesized in a single reaction and removed the need for s1 nuclease digestion to remove the 5' hairpin structure normally generated in cdna synthesis.19826294322
genetic heterogeneity within individual bovine rotavirus isolates.the genomic rna patterns of six different bovine rotavirus isolates were analyzed on high-percentage polyacrylamide gels (12.5, 13.6, and 17.5%). in contrast to the rna patterns exhibited by conventional gel systems, those on the high-percentage gels showed an improvement in segment resolution which consequently aided in the detection of extensive band splitting in these patterns. the ability to clone out various electrophoretically distinct virus subpopulations from each of the six isolates pro ...19826294331
isolation and identification of swine rotavirus in taiwan.large numbers of viral particles resembling rotavirus were detected with negative stained electron microscopy in bacteria free fecal filtrate obtained from 10-day old diarrheal suckling piglets of a conventional pig farm in taiwan. the clinical signs of vomiting and diarrhea were reproduced in colostrum deprived piglets artificially infected with the fecal filtrates. rotavirus particles persisted in the fecal samples after two in vivo serial passages, and was not seen in the uninfected control a ...19826291876
association of viral particles and viral proteins with membranes in sa11-infected cells.electron microscopy after negative staining of sa11-infected cell homogenates revealed that most of the viral particles are associated with membrane-like material. many of the particles seemed to be fully enveloped in a membrane. this association could also be detected by the observed cosedimentation of viral proteins and cell membranes. pulse-chase experiments showed that viral glycoproteins rapidly associate with membranes, whereas most of the structural proteins appearing in the soluble fract ...19826294346
detection of human rotavirus by reversed passive hemagglutination (rpha) using antibody against a cultivable human rotavirus as compared with electron microscopy (em) and enzyme-linked immunosorbent assay (elisa). 19826294488
new agents in diarrhea. 19826294627
new opportunities for development of safe, effective live virus vaccines.effective vaccines are not available for most viral diseases. this situation may soon change when the full force of contemporary molecular biology is applied to immunoprophylaxis. in certain viral diseases, particularly those affecting the respiratory and gastrointestinal tracts, live attenuated vaccines are needed to confer effective protection. until now the major obstacle to success has been genetic instability. it may be possible to construct stable, satisfactorily attenuated mutants by clon ...19826295011
improved specificity of elisa for rotavirus. 19826295355
pathogenesis of rotavirus infection in mice.three parameters of rotavirus infection, i.e., clinical disease, viral antigen in infected intestines, and infectious virus in feces, were assessed in infant mice nursed by mothers with or without preexisting rotavirus antibody. diarrhea was the only consistent sign of clinical disease, and its course followed that of infection by about 1 day. infected intestinal epithelial cells, except crypt cells, were observed by immunofluorescence microscopy in the duodenum, jejunum, ileum, and colon. infec ...19826292110
passive immunity in calf diarrhea: vaccination with k99 antigen of enterotoxigenic escherichia coli and rotavirus.twenty-four pregnant cows were vaccinated intramuscularly with k99 extract from enterotoxigenic escherichia coli and inactivated rotavirus as follows: six cows were injected with 2 ml of oil-adjuvanted vaccine; six cows were injected with 0.5 ml of oil-adjuvanted vaccine; six cows were injected with 4 ml of aluminum hydroxide-adjuvanted vaccine twice with a four-week interval; and six cows were unvaccinated as controls. calves born to these cows were challenged with enterotoxigenic e. coli at 6 ...19826288567
[efficacy testing of inactivated rotavirus vaccine in a dairy cattle herd]. 19826291485
genetic relatedness among human rotaviruses as determined by rna hybridization.viral rnas from human rotaviruses were compared by gel electrophoresis and by hybridization to probes prepared by in vitro transcription of two well-characterized laboratory strains (wa and ds-1). also, the viral rnas were compared by hybridization to probes prepared from three of the test viruses. thirteen specimens (diarrheal stools) were obtained from infants and children 5 to 21 months old on a single day at the emergency ward of the caracas children's hospital, and an additional specimen wa ...19826288569
histocompatibility types and antiviral antibodies in a diverse group of individuals.a study was made of the possible relationship between histocompatibility (hla) antigens of the a and b loci and antibodies to cytomegalovirus, influenza a (victoria strain), measles, rotavirus, vaccinia, and varicella/zoster. a large and diverse group of unselected individuals was studied. a possible relationship was detected between the presence of the antigen b15 and a lack of circulating measles antibodies. the study group was divided into three sections: (a) healthy individuals, (b) "renal d ...19826288632
isolation of human rotaviruses in primary cultures of monkey kidney cells.we succeeded in isolating human rotaviruses from the feces of gastroenteritis patients by using roller cultures of primary cynomolgus monkey kidney cells with trypsin in the maintenance medium but without concentration and trypsin treatment of the inocula at each passage level. these cells were found to be more sensitive than ma-104 cells (derived from fetal rhesus monkey kidney) for the propagation of human rotaviruses. polyacrylamide gel electrophoresis of the genome rna revealed that there we ...19826288768
rotavirus antibodies in hanuman langurs (presbytis entellus).serum samples from wild hanuman langurs (presbytis entellus) from mysore state, india, were compared to samples from a laboratory colony from davis, calif., for antibodies to rotavirus, which is an important cause of gastroenteritis in mammals. animals from the laboratory colony had a higher frequency and higher levels of antibody than wild animals. it is likely that wild populations of langurs have a much lower incidence of rotaviral infection than laboratory populations, which are exposed to b ...19826288954
heterogeneity in the structural glycoprotein (vp7) of simian rotavirus sa11. 19826291238
investigation of genetic interaction between simian rotavirus sa11 and reovirus.rotavirus and reovirus are physically and genetically very similar. their genetic interaction would have important implications for understanding both the epidemiology of rotavirus and the biological basis of rotavirus pathogenicity. a permissive line of rhesus macaque kidney cells, ma104, was infected with the simian rotavirus sa11 and various temperature sensitive mutants of reovirus (type 3 groups a, b, c, d, g, type 1 m79, and type 2 122). the mixed cell infections were carried out at permis ...19826289051
pathogenic mechanisms and new perspectives in the treatment and prevention of enteric infections.enteric infections cause more than a billion episodes of diarrhoeal disease in humans each year killing many millions of people, especially young children, in developing countries. recent progress, reviewed in this article, has enabled that a specific pathogen now can be isolated in the majority of patients with acute diarrhoea, and has also elucidated fundamental pathogenic mechanisms and their pathophysiological effects for several of these agents. based on this understanding it now seems poss ...19826289485
comparison of direct and indirect enzyme immunoassays with direct ultracentrifugation before electron microscopy for detection of rotaviruses.a direct and an indirect enzyme immunoassay (eia) were evaluated against a standard of electron microscopy after direct ultracentrifugation of the specimen for their performances in detecting rotaviruses. the indirect eia had variable background activity which influenced test specificity. the indirect eia control (test system without the detector antibody) plus a regression line (which reflected background noise) improved test specificity. however, the results of direct eia (rotazyme; abbott lab ...19826286720
isolation and genetic characterization of temperature-sensitive mutants of simian rotavirus sa11. 19826285605
development of a method for detection of human rotavirus in water and sewage.the simian rotavirus sa11 was used to develop a simple, reliable, and efficient method to concentrate rotavirus from tap water, treated sewage, and raw sewage by absorption to and elution from filterite fiberglass-epoxy filters. sa11 adsorbed optimally to filterite filters from water containing 0.5 mm alcl3 at ph 3.5. filter-bound virus was eluted with 0.05 m glycine-naoh supplemented with 10% tryptose phosphate broth at ph 10. sa11 was quantitated by plaque assay, whereas human rotavirus was de ...19826285825
rescue and serotypic characterization of noncultivable human rotavirus by gene reassortment.thirty-three of 50 noncultivable human rotavirus strains from a variety of locations were successfully rescued by gene reassortment. the serotype of each of the 33 strains was investigated by a qualitative cytopathic effect neutralization assay. nineteen strains resembled the previously characterized human rotavirus serotype wa, whereas three strains were serologically related to the ds-1 strain. eleven strains appeared to be serotypically distinct from the wa and ds-1 strains and thus apparentl ...19826286486
colostral and milk antibody titers in cows vaccinated with a modified live-rotavirus-coronavirus vaccine.colostral and milk whey rotavirus (rv) and coronavirus (cv) antibody titers stimulated in 15 beef heifers by vaccination with a modified live-rv-cv vaccine were compared with titers in 15 nonvaccinated heifers. geometric mean antibody titers to rv in colostral and 3-day milk whey from vaccinated heifers were 2,807 and 92, respectively, and in control heifers were 1,613 and 71, respectively. geometric mean antibody titers to cv in colostral and 3-day milk whey of vaccinated heifers were 877 and 1 ...19826290437
a method for the purification of rotaviruses and adenoviruses from faeces.rotaviruses and non-cultivable enteric adenoviruses were purified from large volumes of faecal extracts using polyethylene glycol precipitation, centrifugation through 45% w/v sucrose and segregation by density in a cesium chloride density gradient. yields were high and the preparations were pure enough to use in the production of type-specific antisera and in viral polypeptide analysis. human rotavirus particles of density 1.38 g/ml were shown to be non-infectious for llc-mk2 tissue culture cel ...19826290520
antigenic relationships among some animal rotaviruses: virus neutralization in vitro and cross-protection in piglets.the serotype, rna electropherotype, and cross-protection properties of rotaviruses isolated from canine, simian, porcine, and human species were compared. the bovine strain b:usa:78:1a and the canine strain c:usa:81:2 were adapted to cell culture and cloned in this study. the other viruses, i.e., simian strain s:usa:79:2, porcine ohio state university strain p:usa:77:1, and human strain wa, were already cell culture adapted, although they were further cloned for this work. the serum neutralizati ...19826290530
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