| [visualization by electronmicroscopy of 28 nm virusparticles (astroviruses) in faeces of newborns with acute nonbacterial gastroenteritis (author's transl)]. | on occasion of an epidemic of acute nonbacterial gastroenteritis virus particles were visualized by electronmicroscopy in the faeces of 76 newborns; these particles had the following properties: mean diameter 28 nm; ether-resistent, stable at ph 3.0; buoyant density 1.33--1.34 g/ml in cscl. about 10% of these particles had a definite star-like structure on their surface. due to these properties the virusparticles were considered to be astroviruses. the virus was not cytopathogenic for cell cultu ... | 1978 | 34952 |
| astrovirus-associated gastroenteritis in children. | in a small astrovirus-associated outbreak of gastroenteritis in a ward of a local children's hospital two out of five children with symptoms excreted astrovirus particles. no astrovirus particles were found in faeces from the remaining asymptomatic child, and no other viral or bacterial pathogens were found in any of the children. virus excretion persisted for only a few days. rising antibody titres to the astrovirus particles were demonstrated in one child, and igm was also demonstrated in this ... | 1978 | 101556 |
| isolation of small viruses resembling astroviruses and caliciviruses from acute enteritis of calves. | small round viruses (srv) were isolated from the faeces of diarrhoeic calves from three farms. all three srv preparations caused diarrhoea experimentally in gnotobiotic calves. each preparation contained viral particles of two morphological types, "astrovirus-like" and "calicivirus-like", and from one preparation the two particle types were separated from each other. the calicivirus-like agent ("newbury agent") was 33 nm in diameter, and caused diarrhoea in gnotobiotic calves with villous atroph ... | 1978 | 102800 |
| astrovirus gastroenteritis age distribution of antibody. | astrovirus antibody was detected by immunofluorescence using infected primary human embryo kidney cultures as antigen. of 87 oxford children aged 0--10 years, only 7% in the 6 to 12-month-old group had antibody. the percentage of children having evidence of past infection rose progressively in the 1--4 age range and 75% of the 5 to 10-year-old group possessed astrovirus antibody. fifty-four (77%) of a group of 70 young adults likewise had antibody. | 1978 | 102914 |
| astrovirus infection in volunteers. | an extract and a filtrate prepared from feces of a child with mild gastroenteritis were shown by electron microscopy to contain numerous astrovirus particles and were given to eight volunteers by mouth. one subject developed diarrheal illness and concurrently shed large amounts of astrovirus in feces, and one other had mild constitutional symptoms with a lower level of virus shedding. nine other volunteers were given fecal filtrate from the volunteer with diarrhea, and astrovirus shedding subseq ... | 1979 | 113503 |
| pathogenesis of diarrhoea caused by astrovirus infections in lambs. | experimental infection of 2-day-old gnotobiotic lambs with lamb astrovirus produced mild diarrhoea after an incubation period of about 48 hours. no other clinical symptoms developed. infection was studied by immunofluorescent and histological examination of tissues from the lambs. astroviruses infected only mature villus epithelial cells and subepithelial macrophages in the small intestine, where they produced partial villus atrophy. infected enterocytes were replaced with cuboidal cells from th ... | 1979 | 116623 |
| [role of bacteria and viruses in the etiology of acute gastroenteritis in children]. | | 1978 | 211023 |
| stool viruses in babies in glasgow 2. investigation of normal newborns in hospital. | the stools of 37 newborn babies born in hospital were examined for the presence of virus. an extract of every stool passed by each baby was examined in the electron microscopy and inoculated into cell cultures. the babies were delivered in four separate maternity units (a-d). all the babies from unit a and c(9 babies) were found to be excreting rotavirus though none showed any evidence of diarrhoea. two of the babies also excreted astrovirus. subsequently unit a was closed for cleaning and, on r ... | 1978 | 212478 |
| [coronavirus and "astrovirus" observed in stools of children with gastroenteritis (author's transl)]. | in a year's survey (december 1976-november 1977) of 190 children admitted to hospital with acute gastroenteritis, an "aetiological" agent was found in stools by electron microscopy in 41% of cases. rotavirus were found in 34% of patients. we also found coronavirus-like particles and astrovirus-like particles in 25 and 5 stools, respectively. improvements are awaited to demonstrate the responsibility of these virus in gastroenteritis. | 1978 | 214002 |
| [virusenteritis in childhood (author's transl)]. | about 20% of infantile enteritis are caused by bacterial infections. the most cases of non bacterial infantile enteritis are supposed to be viral infections. arguments for the existence of enterotropic viruses arised the first time in 1943. since the middle of the fifties, various kinds of enteroviruses are known to be causative agents of infantile gastroenteritis. the same is true occasionally for some types of adenovirus. in 1973 the norwalk-agent was discovered provocing enteritis mainly in a ... | 1979 | 222939 |
| viral intestinal infections of animals and man. | | 1979 | 232863 |
| comparison of the features of astroviruses and caliciviruses seen in samples of feces by electron microscopy. | astroviruses and caliciviruses may both be observed in the feces of babies by electron microscopy and are two of the viruses whose relationship to infantile diarrhea is still being established. although similar in size and in their star-shaped surface configurations, they differ in detailed structure. the astrovirus has a round unbroken edge, a six-pointed star with a white center, and surface hollows that are triangular. the calicivirus has a feathery edge, a six-pointed star with a dark hollow ... | 1979 | 438551 |
| [viral diarrheas]. | it is now well known that several viruses are responsible for acute diarrhoea or gastroenteritis in both children and adults. these viruses are difficult to identify since most of them cannot be isolated by stool cultures on cells. the reality of proven reinfection by some of these organisms is not always clearly understood, even though the existence of several serotypes in the same group (notably rotavirus) can be blamed, and this explains why vaccines are difficult to develop. | 1992 | 1313558 |
| viral agents associated with infantile gastroenteritis in nigeria: relative prevalence of adenovirus serotypes 40 and 41, astrovirus, and rotavirus serotypes 1 to 4. | sixty-six stool specimens from infants with diarrhoea in nigeria were examined for the presence of viral pathogens. rotaviruses were found in 25.8% of specimens and astroviruses in 1.5%. serotypes were determined for 47.1% of the rotavirus positive specimens, all of which were serotype 1. rna analysis revealed no unusual electrophoretic profiles. no enteric adenoviruses were detected. in contrast, in a parallel study conducted in the uk, rotaviruses (including serotypes 1, 2 and 4) accounted for ... | 1992 | 1323591 |
| viral gastrointestinal infections. | numerous disease-causing viruses of the gastrointestinal tract have been described. the diseases that they induce range from subclinical to fatal gastrointestinal or systemic organ infection. recent advances in molecular biology and virus culture techniques, as well as improvements in animal models of these infections, have increased our understanding of pathologic processes associated with these viruses. although our overall understanding of these viruses has improved to the extent that many mo ... | 1992 | 1324891 |
| astroviruses and caliciviruses: emerging enteric pathogens. | acute, infectious gastroenteritis is an extremely common disease that contributes significantly to morbidity and mortality worldwide. in the united states, it is the second most frequent illness encountered in families. while this illness generally runs a self-limited course, it may be temporarily incapacitating and impact substantially on numbers of days lost from work or school. at present, 30-40% of infectious gastroenteritis cases in the united states are attributable to viral agents, while ... | 1992 | 1365533 |
| 3' terminal nucleotide sequence of human astrovirus type 1 and routine detection of astrovirus nucleic acid and antigens. | human astrovirus type 1 was purified by caesium chloride density-gradient centrifugation and the virus was located using an immunodot blot technique with polyclonal rabbit serum, which reacted with all five serotypes. the virus banded with a density of 1.33 g/ml. rna was extracted from the purified virus, converted into double-stranded cdna, using an oligo(dt) primer, and cloned into plasmid and m13 vectors. the sequence of the 3' end of astrovirus rna adjacent to the poly(a) tract was determine ... | 1992 | 1430061 |
| mechanism of astrovirus entry into graham 293 cells. | astroviruses are intestinal pathogens associated with gastroenteritis in man and animals. the mechanism of internalization into host cells has not been reported previously. the cell entry pathway of serotype 1 human astrovirus into 293 cell line was studied biochemically and morphologically. viral infection was monitored by indirect immunofluorescence. infected cells were treated with the lysosomotropic agents ammonium chloride, methylamine, and dansylcadaverine or the ionophore monensin to rais ... | 1992 | 1474377 |
| the frequency of astrovirus as a cause of diarrhea in baltimore children. | | 1992 | 1528651 |
| confirmation of a viral agent as a cause of acute diarrhea. | | 1992 | 1573501 |
| astrovirus-associated diarrhea among guatemalan ambulatory rural children. | fecal excretion of astroviruses was monitored in 321 children, 0 to 3 years old, living in the rural highlands of guatemala. during the longitudinal study, from february 1987 to february 1989, we examined 5,000 stool specimens, including 1,805 collected during 1,369 episodes of diarrhea, 830 collected during the convalescent week, and 216 and 244 collected 2 weeks and 1 week, respectively, before the onset of diarrhea. routine specimens were taken once a month from every child who had been free ... | 1992 | 1583111 |
| the 3' terminal sequence of a human astrovirus. | we have determined the sequence for 1,000 bases from the 3' terminus of a human astrovirus serotype 1 isolated in newcastle. this is the first sequence reported for a representative of this virus family. we find one open reading frame which terminates 83 bases from a poly a tail. the 3' non-coding-region has similarities to some picornavirus termini. however the amino acids specified by the coding region have no significant homology to the picornavirus protein 3d, encoded at the 3' terminus of t ... | 1992 | 1605739 |
| astroviruses as a cause of gastroenteritis in children. | infection with astroviruses has been associated with gastroenteritis in children, and serologic surveys indicate that this infection may be frequent. the importance of astroviruses as agents of gastroenteritis has not been shown in a controlled study, however. | 1991 | 1645459 |
| electron microscopic reporting of gastrointestinal viruses in the united kingdom, 1985-1987. | we examined some epidemiological features of the viruses associated with gastrointestinal illness, using national data reported by electron microscopists in the united kingdom. during the 3 years analyzed (1985-1987), a total of 1,993 positive detections of astroviruses, caliciviruses, coronaviruses, and small round structured viruses (srsvs) were reported. in 1 year of this period, 8,210 rotaviruses were reported. more than 90% of the astroviruses and caliciviruses were detected in children und ... | 1991 | 1652619 |
| viral gastro-enteritis in children in malawi. | in a 2-month survey of 186 children with gastro-enteritis attending an out-patient clinic in malawi, 42% were infected with rotavirus (hrv), 9% cryptosporidium, 4.2% adenovirus, 1.2% astrovirus and 0.6% norwalk agent and small round featureless viruses. we believe this to be the first report of hrv in malawi and the first of astrovirus in africa. almost all the hrv infections were in children under 12 months old, 40% were in children under 6 months and 64% of children were being breastfed at pre ... | 1990 | 1694637 |
| a dot-blot hybridization procedure for the detection of astrovirus in stool samples. | we have developed a nucleic acid dot-blot hybridization test for the detection of astroviruses in stool samples. the test was not as sensitive as electron microscopy for the detection of low numbers of well preserved astrovirus particles, but was able to identify astroviruses in stools containing particles of indistinct morphology. in total, this procedure identified astroviruses in more samples than did electron microscopy, and the data indicate that the incidence of astroviruses may be substan ... | 1991 | 1718770 |
| detection of astrovirus in pediatric stool samples by immunoassay and rna probe. | two new astrovirus assays, a rapid biotin-avidin enzyme immunoassay (eia) and rna probe hybridization, were developed and compared with an established astrovirus assay, an indirect eia, and immune electron microscopy. sensitivity and specificity were evaluated by using a screening panel of 22 astrovirus-positive and 305 astrovirus-negative fecal specimens. the biotin-avidin assay was equivalent in performance to the reference indirect assay, and both could detect about 10 ng of viral protein. al ... | 1991 | 1774241 |
| [occurrence of human astrovirus in são paulo city, brazil]. | human astrovirus was detected during a 13-month longitudinal study of the incidence of diarrhoea viruses among hospitalized children (less than 2 years of age) in a pediatric clinic of the city of s. paulo (university hospital). serial fecal samples (intervals of 4 days) were collected from 146 children with and without acute diarrhoea at admission and during their stay in the hospital. two (3%) of the 67 children with diarrhoea were positive at admission to the clinic by the highly sensitive as ... | 1991 | 1784973 |
| astrovirus in faeces of children with acute gastroenteritis in rio de janeiro, brazil. | | 1991 | 1842447 |
| astroviruses as a cause of nosocomial outbreaks of infant diarrhea. | during a 16-month study period at a children's hospital, 32 children developed nosocomial gastroenteritis caused by astroviruses. twenty-five of these occurred during 2 epidemic outbreaks in medical and surgical infants' wards. from the community, 13 confirmed cases were admitted during the study period. both community-acquired and nosocomial cases occurred during autumn, winter and early spring. the attack rates during outbreaks ranged between 7 and 62% and were highest among children with unde ... | 1991 | 1876467 |
| astrovirus and adenovirus associated with diarrhea in children in day care settings. | the relative importance of astrovirus and adenoviruses as etiologic agents of diarrhea among children in day care was examined. stool specimens from this prospective study were screened for both astrovirus and adenovirus hexon with two new indirect double-antibody assays and for enteric adenoviruses with an eia specific for serotypes 40 and 41. astrovirus was detected in a significantly greater percentage of children with diarrhea (4%, 21/524) than of those without (less than 1%, 1/138) (p less ... | 1991 | 1894931 |
| pathogenesis of gut virus infection. | in summary, the pathogenesis of many gut virus infections remains uncertain. however, human and animal studies indicate that the majority of gut viruses infect villous enterocytes. viruses appear to have different affinities for enterocytes at different sites on the villus. infection of enterocytes leads to cell death, extrusion into the lumen, and villous atrophy when the rate of cell production in the crypts cannot keep pace with the rate of enterocyte loss. this results in a reduced surface a ... | 1990 | 1962725 |
| human, small round structured viruses, caliciviruses and astroviruses. | epidemiological studies on srsvs, human calicivirus and astroviruses have been limited by the problems of establishing them in cell culture and the inability to transmit them to animals or to use strains from animals as a source of antigen for diagnostic tests. the use of em and the subsequent development of rias and eias in a few research centres has shown that they are a cause of outbreaks and sporadic cases of diarrhoea and vomiting. srsvs have increasingly been recognized as a major cause of ... | 1990 | 1962728 |
| temporal synthesis of proteins and rnas during human astrovirus infection of cultured cells. | astroviruses are nonenveloped particles with a distinctive star-shaped surface structure that have been detected by electron microscopy in stool samples from humans and animals with gastroenteritis. we examined the patterns of macromolecular synthesis in astrovirus-infected cells with a goal of establishing a molecular basis for taxonomic classification. trypsin is required for continuous replication of astrovirus in cultured cells; however, during a single cycle of infection, astrovirus antigen ... | 1991 | 1987373 |
| diagnosis of astrovirus gastroenteritis by antigen detection with monoclonal antibodies. | an enzyme-linked immunosorbent assay (elisa), based on monoclonal antibodies to the astrovirus group antigen, was designed for the detection of astroviruses in stools of patients with gastroenteritis. compared to immune electron microscopy used as the standard test, the sensitivity of the astrovirus elisa was 91% (31/34) and the specificity was 96% (54/56). all five of the known astrovirus serotypes could be detected in 16 samples on which serotyping was done. in tests on 155 stools containing o ... | 1990 | 2105359 |
| cytopathic astrovirus isolated from porcine acute gastroenteritis in an established cell line derived from porcine embryonic kidney. | a cytopathic astrovirus was isolated from pigs with acute diarrhea in an established cell line that was derived from porcine embryonic kidneys with the aid of trypsin. the virus showed a distinct cytopathic effect characterized by an enlargement of cells and the appearance of fine granules in the cytoplasm. porcine astrovirus was shown to have an rna genome, as determined by the effect of 5-iodo-2'-deoxyuridine on its replication, and five polypeptides with molecular masses of 13,000, 30,000, 31 ... | 1990 | 2107200 |
| immunological characterization of the marin county strain of astrovirus. | marin county virus (mcv) was isolated from a stool suspension and serially propagated in human embryonic kidney cell cultures. mcv particles in stool and cell-propagated virus stocks showed reactivity by immune electron microscopy (iem) with rabbit antiserum to astrovirus type 5. mcv antigen was also detected in two mcv stool samples by enzyme immunoassay (eia) with an astrovirus group-specific monoclonal antibody. acute and convalescent sera from 3 of 3 mcv-infected patients showed seroconversi ... | 1990 | 2107802 |
| in vitro effect of synthetic flavanoids on astrovirus infection. | in this study we investigated the activity of halogeno-, cyano- and amidino-isoflavenes, isoflavans and flavans on the multiplication of human astroviruses. these are naked small round viruses which have been recognized as causative agents of human gastroenteritis, and whose capsid proteins are similar to those of picornaviruses. although all drugs tested caused a dose-dependent reduction of viral antigen synthesis as monitored by immunofluorescence, the chloro derivatives were the most effectiv ... | 1990 | 2116755 |
| growth and characterisation of human faecal astrovirus in a continuous cell line. | we report conditions for the growth of human faecal astrovirus in a continuous colonic carcinoma cell line (caco-2). purified particles contained three polypeptides, one of which (24k) appeared loosely held on the exterior. | 1990 | 2117433 |
| viral agents of gastroenteritis. public health importance and outbreak management. | each year, infectious gastroenteritis causes greater than 210,000 children in the united states to be hospitalized and 4-10 million children to die worldwide. since the mid-1970s, knowledge has increased dramatically concerning the viral agents that are responsible for much of this public health burden. rotavirus, the most common cause of diarrhea among children, infects virtually every child in the united states by the age of 4 years and causes potentially lethal dehydration in 0.75% of childre ... | 1990 | 2157945 |
| six-year retrospective surveillance of gastroenteritis viruses identified at ten electron microscopy centers in the united states and canada. | to identify the prevalence, seasonality and demographic characteristics of patients with viral gastroenteritis, we reviewed 6 years of retrospective data on viral agents of gastroenteritis screened by electron microscopy at 10 centers in the united states and canada. from 52,691 individual electron microscopic observations, a virus was detected in 16% of specimens, and the yearly positive detection rate among centers ranged from 8 to 34%. rotavirus was the agent most commonly observed (26 to 83% ... | 1990 | 2172903 |
| cultivation and partial characterization of bovine astrovirus. | bovine astrovirus serotype 2 (us2) was adapted to primary neonatal kidney cell (nbk) cultures by the addition of 50 micrograms ml-1 of trypsin in the medium. infectious virus was released from the cells within 7 days post-infection in early passages and within 3 days in later passages. in the absence of trypsin, neither passage of infected cells nor release of infectious virus occurred. the virus was shown to be similar to the fecal astrovirus by a neutralization test and by ultrastructural stud ... | 1989 | 2495698 |
| plaque quantitation and virus neutralization assays for human astroviruses. | astroviruses, 28 nm-diameter, rna-containing viruses which have been implicated in gastroenteritis can be cultivated in cell cultures containing trypsin, but do not show distinguishable cytopathic effects. however, with the 5 known astrovirus serotypes which we have been able to cultivate, 3 (types 1, 2, and 5) formed well-defined plaques in llcmk2 cell cultures under an agar overlay containing trypsin. a virus neutralization assay based on plaque reduction was applied to these 3 serotypes. it w ... | 1989 | 2512894 |
| outbreaks of astrovirus type 1 and rotavirus gastroenteritis in a geriatric in-patient population. | two outbreaks of viral gastroenteritis occurred in seven psychogeriatric wards of a 469-bed psychiatric hospital. the outbreaks occurred over an eight-week period; the first affected 30 people and rotavirus was detected in 12 of 14 persons from whom faecal specimens were available. the second affected 32 people (15 of whom were affected in the previous outbreak) and astrovirus was detected in 5 of the 24 people from whom specimens were available. specific igm to astrovirus was demonstrated in 3 ... | 1989 | 2570110 |
| an outbreak of gastroenteritis in a home for the elderly associated with astrovirus type 1 and human calicivirus. | we describe an outbreak of gastroenteritis, which lasted for 22 days in a residential home for the elderly. the outbreak was biphasic and affected 34/42 (80%) residents and 13/29 (44%) members of the staff. calicivirus was associated with cases of illness during the first 9 days of the outbreak, and astrovirus type 1 with cases arising between days 16 to 22. although the symptoms were generally mild, the resources required and the inconvenience caused were considerable. | 1987 | 2826678 |
| an electron microscopical investigation of faecal small round viruses. | a retrospective study of small round featureless viruses (srvs) initially identified by negative-staining electron microscopy of stool samples was performed. a variety of technique, including immunoelectron microscopy and caesium chloride gradient centrifugation, was applied in an attempt to classify further these viruses. over a four-year period, 64 srv-positive samples were reported (1.8% of the stool samples sent for electron microscopy and 6.2% of the total number of positive samples), of wh ... | 1988 | 2832539 |
| a three-year diagnostic and epidemiological study on viral infantile diarrhoea in rome. | rotavirus infection was demonstrated in 168 (29.3%) of 573 children hospitalized for acute diarrhoea in rome between january 1982 and december 1984. laboratory diagnosis of these infections was made by transmission electron microscopy and enzyme immunoassay techniques with an overall agreement of 91.3%. astroviruses, adenoviruses and small round viruses were detected in the faeces of 36 patients (6.4%). whereas in 1982 rotavirus positive patients were clustered in the winter and following spring ... | 1988 | 2833404 |
| chronic enteric virus infection in two t-cell immunodeficient children. | enteric virus infections were studied in two children with congenital t-cell immunodeficiency. one patient (lc) with cartilage hair hypoplasia developed persistent diarrhea and malabsorption following acute gastroenteritis. electron microscope (em) examination of feces revealed excretion of rotavirus for more than 450 days with concurrent astrovirus infection for at least 225 days, associated with the persistent diarrhea. prolonged infection with poliovirus type 2 following vaccination had previ ... | 1988 | 2835434 |
| marin county agent, an astrovirus. | | 1987 | 2888967 |
| natural and experimental astrovirus infection of cats. | | 1987 | 2956753 |
| other viruses with etiologic roles in childhood gastroenteritis. | rotaviruses and norwalk-like viruses are the two groups of viruses most frequently associated with gastroenteritis, but as outlined in this review several other viral agents have also been associated with acute gastroenteritis. the gastroenteritis viruses are generally fastidious, and thus traditional cell culture isolation and detection procedures are not applicable; therefore electron microscopy and immunoelectron microscopy remain among the most powerful techniques for studying these viruses. ... | 1986 | 3003721 |
| detection of astrovirus-like in diarrhoeic stool and its coexistence with rotavirus. | | 1985 | 3010433 |
| an eight-year study of the viral agents of acute gastroenteritis in humans: ultrastructural observations and seasonal distribution with a major emphasis on coronavirus-like particles. | during an 8-yr period, 862 stool specimens from patients with gastroenteritis were examined by electron microscopy after negative staining with 2% phosphotungstic acid (ph 6.5). forty-one percent of the specimens submitted over an 8-yr period were determined to be positive for virus or viruslike particles belonging to one or more of seven morphologically distinct viral groups. coronavirus-like particles (cvlps) were present in 69.8% of the positive stool specimens. membranous profiles containing ... | 1986 | 3011353 |
| [virus-related gastroenteritis]. | | 1987 | 3026769 |
| novel agents of viral enteritis in humans. | considerable information has recently emerged regarding certain "groups" of novel viruses associated with gastroenteritis in humans. the viruses reviewed here are 20-35 nm in diameter and can be detected in the stools of acutely ill individuals with gastroenteritis. these viruses can be conveniently divided into four "groups": norwalk-like agents, caliciviruses, astroviruses, and other small round viruses. the evidence for the etiologic association of these agents with gastroenteritis varies fro ... | 1987 | 3027199 |
| a survey of enteric viruses of turkey poults. | intestinal samples from 91 turkey flocks between 1 day and 5 weeks of age were examined for enteric viruses using electron microscopy and electropherotyping. these flocks originated from eight operations in six states. individual flocks were sampled only once. at the time of sampling, 31 flocks were considered normal/healthy and 60 were considered to have enteric disease. the most frequently identified viruses from diseased flocks were astroviruses (78%) and rotavirus-like viruses (rvlvs) (67%). ... | 1987 | 3034232 |
| small round viruses: classification and role in food-borne infections. | since the first observation of norwalk virus in the electron microscope in 1972, many different small virus particles in the size range 20-40 nm have been described world-wide in association with outbreaks of gastroenteritis. progress characterizing these agents has been hampered by the relatively small numbers of particles present in clinical material and the lack of success in culturing them. although the relationship between some of these viruses remains confusing, a number of distinct groups ... | 1987 | 3036438 |
| comparative pathology of infection by novel diarrhoea viruses. | examination of diarrhoeic faeces in the electron microscope often reveals viruses that are presumed to be enteropathogenic. lesions caused by novel rotaviruses were similar to those of group a rotaviruses, but enterocyte syncytia were seen which are probably pathognomonic for novel rotaviruses. in adenovirus infection in piglets, mature enterocytes were infected and destroyed; intranuclear inclusion bodies were seen in infected enterocytes. calici-like viruses infected mature enterocytes in calv ... | 1987 | 3036441 |
| the diagnostic gap in diarrhoeal aetiology. | it is well established that rotaviruses of group a are the most important cause of severe diarrhoea in children. the causes of most cases of infectious diarrhoea still remain unidentified, however, and there must be other viruses to be found. 'novel' rotaviruses have recently been discovered, mainly in animals (serogroups b and c in pigs and humans, d in birds, and one or more further groups in sheep and other mammals). except for the group b virus which has caused widespread outbreaks of quite ... | 1987 | 3036443 |
| virus and virus-like particles in the faeces of cats with and without diarrhoea. | negative staining electron microscopy was used to identify viruses in 166 normal and 62 diarrhoeal faecal samples from 208 cats admitted to an animal shelter during a 16-month period (march 1984 to june 1985). on the basis of size and shape 7 distinct viral types were detected: 24 nm parvovirus-like particles, 30 nm astrovirus, 30 nm picornavirus-like particles, reovirus, rotavirus, coronavirus and a 75 nm "togavirus-like" particle. the incidence of these particles in the 208 cats was 11%, 7%, 6 ... | 1987 | 3039960 |
| enteric viral infections of turkey poults: incidence of infection. | four flocks from one commercial market-turkey operation in ohio were monitored for the presence of enteric viruses. each flock was sampled at intervals from placement until at least 7 weeks of age; sampling was more frequent in the first 4 weeks of life. the earliest infections detected were astrovirus infections or combination infections of astrovirus and rotavirus-like virus (rvlv) or astrovirus and rotavirus. during the first 4 weeks of life, astrovirus was the most frequently detected virus, ... | 1987 | 3039964 |
| astroviruses: human and animal. | the name astrovirus was used by madeley and cosgrove in 1975 to describe a small round virus (approximately 28 nm diameter) with star-like appearance on electron microscopy. it was first seen in faeces from a few children with gastroenteritis. an aetiological role in gastroenteritis has since been confirmed. the virus causes a mild illness after an incubation period of 3-4 days. antibody studies indicate that infection is widespread and, in britain, mainly occurs in the 2-5 year age group. outbr ... | 1987 | 3109854 |
| the development and evaluation of radioimmune assays for the detection of immune globulins m and g against astrovirus. | the development and evaluation of radioimmune assays for the detection of igm and igg antibodies to astrovirus are described. the test was shown to be sensitive and specific, and suitable for screening large numbers of sera. the use of the assays has established that astrovirus type 1 is prevalent in the united kingdom and that not only infants but also schoolchildren and elderly patients are affected. further evidence is given to support the view that marin county agent is antigenically related ... | 1988 | 3130387 |
| antigenic characterization of cell-cultivated astrovirus serotypes and development of astrovirus-specific monoclonal antibodies. | cultivation of human astroviruses in human embryonic kidney or llcmk2 cell cultures was corroborated for four of the five serotypes originally reported (types 1, 2, 4, and 5). by using type-specific rabbit antisera and immunofluorescence of virus-infected cells, we readily distinguished between serotypes of astrovirus; however, these serotypes showed a high degree of cross-reactivity by enzyme-linked immunoassay, a result indicating the presence of a group antigen. we prepared monoclonal antibod ... | 1988 | 3134491 |
| astrovirus: a cause of an enteric disease in turkey poults. | virus particles of 30 nm diameter and star-shaped morphology were detected in intestinal contents of turkey poults and were identified as astroviruses. seventy-six intestinal samples from 65 commercial turkey flocks between 6 and 35 days of age were evaluated for the presence of astroviruses by immune electron microscopy. astroviruses were frequently detected in intestinal samples from poults that had enteritis and diarrhea of undetermined etiology. astroviruses were geographically widespread an ... | 1986 | 3814010 |
| detection of astroviruses in gut contents of nude and normal mice. brief report. | gut contents of nude and normal mice were examined by electron microscopy in association with an outbreak of diarrhea in a colony of nude mice. virus-like particles with a morphology consistent with previous descriptions of astroviruses of other species were demonstrated in a high percentage of the animals. | 1985 | 3921007 |
| serotypes of bovine astrovirus. | three isolates of bovine astrovirus, one from the united kingdom and two from the united states, possessed common antigens by immunofluorescence and strain-specific antigens by neutralization and were designated as two, and probably three, distinct serotypes. the isolate us2, despite being a different serotype, possessed the same restrictive cell tropism and cytopathology as previously reported for isolate us1, of the m cells of the dome epithelium of the peyer's patches. serotyping of 16 field ... | 1985 | 3935665 |
| astrovirus gastroenteritis. | | 1985 | 4009781 |
| coronavirus-, calicivirus-, and astrovirus-like particles associated with acute porcine gastroenteritis. | | 1985 | 4094270 |
| human astrovirus serotypes. | | 1984 | 6150404 |
| purification and characterization of ovine astrovirus. | astrovirus, purified in aggregated form from epithelial cells of the small intestinal villi of infected gnotobiotic lambs, was shown to have a single-stranded rna genome with an s value of 34 and poly(a) tract. only two major capsid polypeptides were detected with similar mol. wt. of approx. 3.3 x 10(4). | 1981 | 6168736 |
| rapid detection of human viruses in faeces by a simple and routine immune electron microscopy technique. | | 1981 | 6170725 |
| the action of alcohols on rotavirus, astrovirus and enterovirus. | | 1980 | 6182233 |
| detection by electron microscopy of caliciviruses, astroviruses and rotavirus-like particles in the faeces of piglets with diarrhoea. | | 1980 | 6258286 |
| frequency of preclumped virus in routine fecal specimens from patients with acute nonbacterial gastroenteritis. | a low-speed centrifugation technique for the preparation of grids after minimal purification of fecal extracts is described for examination of viruses by direct electron microscopy using negative staining. results showed that adenovirus, astrovirus, rotavirus, and "small round" viruses were frequently shed into the gastrointestinal tract in clumps of variable size. differential centrifugation study showed that a substantial proportion of the virus in the sample was lost in the initial pellet at ... | 1981 | 6263948 |
| [recent findings on the viral etiology of acute gastroenteritis--a review]. | | 1981 | 6265852 |
| experimental escherichia coli and rotavirus infection in lambs. | colostrum-deprived lambs were infected with either enteropathogenic escherichia coli(o9:k30:k99) or rotavirus or a mixture of the e coli and rotavirus. e coli doses of 10(6) and above consistently produced diarrhoea, as did experimental rotavirus infection. when both of the agents were administered, the mortality rate was higher, although the duration of diarrhoea was no greater than that observed when either of the two agents was administered alone. | 1981 | 6265999 |
| the aetiology and diagnosis of calf diarrhoea. | | 1981 | 6266122 |
| viral diarrhea of young animals: a review. | | 1981 | 6277556 |
| [variation of diarrhea viruses detected in japan with special reference to spherical viruses other than rotaviruses (author's transl)]. | | 1981 | 6278755 |
| the electron microscopical and physical characteristics of small round human fecal viruses: an interim scheme for classification. | many of the small round human fecal viruses implicated in outbreaks of nonbacterial gastroenteritis have been collected together and examined under the electron microscope. negatively stained preparations without the addition of antibody were used so that the surface morphology of the virus particles remained clearly visible. it was apparent that several viruses, previously thought to be simply antigenic variants within the norwalk group of viruses, show distinct morphological differences and qu ... | 1982 | 6286860 |
| potassium tartrate-glycerol as a density gradient substrate for separation of small, round viruses from human feces. | cesium chloride density gradients are frequently used for virus concentration or purification in the preparation of human feces for examination by electron microscopy, disruption of some of the fecal viruses occurs if they are pelleted from the density gradient in an additional concentration step. this report highlights an important limitation imposed by the use of cesium chloride as a density gradient substrate in attempting to recover small, round, virus-like particles from feces and suggests ... | 1982 | 6288767 |
| current concepts on etiology and pathogenesis of diarrhoea caused by viruses. | | 1982 | 6298950 |
| viral gastroenteritis. | | 1983 | 6312212 |
| [viral gastroenteritis]. | | 1983 | 6320551 |
| viruses and virus-like particles in the faeces of dogs with and without diarrhoea. | negative staining electron microscopy was used to identify viruses in 157 normal and 29 diarrhoeal faecal samples collected from 156 dogs admitted to an animal shelter during an 8 month period (march to october) in 1982. seven distinct viral types were detected: 21-26 nm parvovirus-like particles, 28-31 nm astrovirus-like particles, a previously undescribed 34-35 nm "round" virus particle, coronavirus, coronavirus-like particles ( cvlp ), rotavirus and papova-like virus. parvovirus-like particle ... | 1984 | 6329156 |
| human viral gastroenteritis. | | 1984 | 6330511 |
| astrovirus in south africa. a case report. | astrovirus was identified in stool samples from a 6-month-old white infant up to 8 days after the onset of gastro-enteritis. large immune aggregates were found after treatment of the faecal specimen with pooled human immunoglobulin. | 1983 | 6408746 |
| [astroviruses]. | | 1983 | 6408803 |
| characterization of a calici-like virus (newbury agent) found in association with astrovirus in bovine diarrhea. | a bovine calici-like virus and astrovirus, present in the same fecal sample from an outbreak of diarrhea, were separated from each other by calf passage. the calici-like virus (newbury agent srv-1) caused anorexia, diarrhea, and xylose malabsorption in gnotobiotic calves aged 17 to 60 days, whereas the bovine astrovirus was nonpathogenic in similar calves. the calici-like virus was shown to be antigenically distinct from a previously described isolate (newbury agent srv-2) by two-way cross-prote ... | 1984 | 6418656 |
| astrovirus-like particles associated with hepatitis in ducklings. | | 1984 | 6424324 |
| astrovirus and breda virus infections of dome cell epithelium of bovine ileum. | a bovine enteric virus antigenically related to the united kingdom isolate of bovine astrovirus was isolated from diarrheic feces, also containing rotavirus, of a calf in florida. the astrovirus infected cell cultures and the epithelial cells of domes in the ileum, and there was cross-immunofluorescence with antiserum to the united kingdom astrovirus. calves infected with astrovirus alone did not develop clinical disease, but when astrovirus was mixed with rotavirus or breda virus 2, the calves ... | 1984 | 6429189 |
| [short review of the literature on viruses demonstrated in the digestive tract of swine]. | | 1984 | 6436971 |
| ultrastructure of the small intestine in astrovirus-infected lambs. | the ultrastructure of the small intestine of gnotobiotic lambs infected with lamb astrovirus was studied. the virus was observed from 14 to 28 h p.i. in mature columnar epithelial cells covering the apical two-thirds of villi. crystalline arrays of virus particles with a centre to centre distance of approx. 29 nm were seen in the cytoplasm and virus particles were also observed in apical pits and tubules and in lysosomes. macrophages containing virus particles in lysosome-like organelles were se ... | 1980 | 6775050 |
| detection of astroviruses in turkey faeces by direct electron microscopy. | | 1980 | 6776680 |
| astrovirus-like, coronavirus-like, and parvovirus-like particles detected in the diarrheal stools of beagle pups. | astrovirus-like, coronavirus-like, and parvovirus-like particles were detected through electron microscopic (em) examination of loose and diarrheal stools from a litter of beagle pups. banding patterns obtained from equilibrium centrifugations in cscl supported the em identification. densities associated with the identified particles were: 1.34 g/ml for astrovirus, 1.39 g/ml for "full" parvovirus and 1.24-1.26 g/ml for "typical" coronavirus. convalescent sera from the pups aggregated these three ... | 1980 | 6778459 |
| detection of astrovirus in the faeces of red deer. | | 1981 | 6791371 |
| astrovirus in autumn infantile gastroenteritis. | | 1981 | 6797800 |
| serial propagation of astrovirus in tissue culture with the aid of trypsin. | astrovirus could be serially passed at least 13 times in primary human embryo kidney (hek) cells when 10 micrograms/ml of crystalline trypsin was incorporated in a serum-free maintenance medium. in the presence of trypsin the virus was also passed and adapted to a continuous line of rhesus monkey kidney cells (llcmk2) and primary baboon kidney (pbk) cells in which it was passed 25 and 16 times respectively, without evidence of diminishing infectivity. attempts to adapt the virus to other cell li ... | 1981 | 6798168 |
| detection of astroviruses in feces of a cat with diarrhea. brief report. | astroviruses were detected by electron microscopy in the feces from a 4 month old kitten with diarrhea. the mean diameter of the viral particles was 28.7 nm, and they showed characteristic five- or six-pointed star-shaped surface configurations. the clinical disease manifested by the cat and the observed morphology of the viral particles are consistent with previous reports on astroviruses of other species. | 1981 | 6798953 |