| [the significance of bredavirus as a diarrhea agent in calf herds in lower saxony]. | the objective of this investigation was to determine the distribution of bredavirus in cattle herds in lower saxony and to evaluate its significance as potential cause of diarrhea in calves. fecal samples and paired blood samples of 119 diarrheic and 46 healthy calves up to two months of age were collected from herds where diarrhea of calves was a problem. fecal samples were examined for breda-, rota- and coronavirus by solid phase immune electron microscopy and by elisa, for k99-positive e. col ... | 1992 | 1322268 |
| breda virus-like particles in pigs in south africa. | | 1992 | 1328635 |
| a serologic investigation for coronavirus and breda virus antibody in winter dysentery of dairy cattle in the northeastern united states. | | 1992 | 1333819 |
| breda virus associated with respiratory disease in calves. | | 1991 | 1659762 |
| association of diarrhea in cattle with torovirus infections on farms. | an epidemiologic survey was performed to determine the incidence of torovirus infections in 2 disease entities of cattle: diarrhea of replacement calves up to 2 months old, and winter dysentery of adult cattle. samples were obtained from 187 diarrheal and 115 healthy calves from 15 farms, as well as 149 diarrheal and 67 healthy cows from 27 farms with or without winter dysentery. enzyme-linked immunosorbent assays for detection of torovirus, rotavirus, and coronavirus antigen in feces, and of to ... | 1991 | 1664668 |
| diagnosis of torovirus infection. | | 1991 | 1672953 |
| equine arteritis virus is not a togavirus but belongs to the coronaviruslike superfamily. | the nucleotide sequence of the genome of equine arteritis virus (eav) was determined from a set of overlapping cdna clones and was found to contain eight open reading frames (orfs). orfs 2 through 7 are expressed from six 3'-coterminal subgenomic mrnas, which are transcribed from the 3'-terminal quarter of the viral genome. a number of these orfs are predicted to encode structural eav proteins. the organization and expression of the 3' part of the eav genome are remarkably similar to those of co ... | 1991 | 1851863 |
| the phylogeny of rna-dependent rna polymerases of positive-strand rna viruses. | representative amino acid sequences of the rna-dependent rna polymerases of all groups of positive-strand rna viruses were aligned hierarchiacally, starting with the most closely related ones. this resulted in delineation of three large supergroups. within each of the supergroups, the sequences of segments of approximately 300 amino acid residues originating from the central and/or c-terminal portions of the polymerases could be aligned with statistically significant scores. specific consensus p ... | 1991 | 1895057 |
| comparison of the genome organization of toro- and coronaviruses: evidence for two nonhomologous rna recombination events during berne virus evolution. | recently, toroviruses and coronaviruses have been found to be ancestrally related by divergence of their polymerase and envelope proteins from common ancestors. in addition, their genome organization and expression strategy, which involves the synthesis of a 3'-coterminal nested set of mrnas, are comparable. nucleotide sequence analysis of the genome of the torovirus prototype, berne virus (bev), has now revealed the results of two independent nonhomologous rna recombinations during torovirus ev ... | 1991 | 1984666 |
| another triple-spanning envelope protein among intracellularly budding rna viruses: the torovirus e protein. | the nucleotide sequence of the berne virus envelope (e) protein gene was determined and its 26.5k translation product was identified by in vitro transcription and translation. computer analysis of the protein sequence revealed the characteristics of a class iii membrane protein lacking a cleaved signal sequence but containing three successive transmembrane alpha-helices in the n-terminal half, much the same as the coronavirus membrane (m) protein. the disposition of the e protein in the membrane ... | 1991 | 2024492 |
| cdna probes for the diagnosis of bovine torovirus (breda virus) infection. | a genomic cdna library of rna from breda virus (brv), a bovine torovirus, was prepared. the nucleotide sequence of the 3' end of the genome was found to be highly conserved (93% identical) between brv and berne virus, the torovirus prototype. cross-hybridization experiments were performed to select berne virus cdna clones for use as probes in a dot hybridization assay; the objective was to detect heterologous torovirus rna in fecal material. a rapid rna extraction method was employed to make the ... | 1991 | 2037666 |
| a clinical and microbiological study of cats with protruding nictitating membranes and diarrhoea: isolation of a novel virus. | fifty cats with the syndrome of protruding nictitating membranes and diarrhoea were compared clinically and microbiologically with nine cats with diarrhoea alone and 17 healthy cats. a novel torovirus-like agent was isolated from 11 cats, including seven of the cats with protruding nictitating membranes and diarrhoea. | 1990 | 2124013 |
| primary structure and post-translational processing of the berne virus peplomer protein. | the nucleotide sequence of the peplomer (p) protein gene of berne virus (bev), the torovirus prototype, was determined. the gene encodes an apoprotein of 1581 amino acids with an mr of about 178k. the open reading frame was cloned behind the t7 rna polymerase promoter and its translation product was identified as the bev p protein precursor by in vivo expression and immunoprecipitation. the deduced amino acid sequence contains a number of domains which are typical for type i membrane glycoprotei ... | 1990 | 2219698 |
| [new types of virus infections of domestic animals in the german democratic republic. 1. serologic survey studies of the distribution of equine torovirus infections in the gdr]. | sera collected from 124 horses were checked by means of the serum neutralisation test against equine bern virus. torovirusspecific antibodies were recordable from 35 percent of all horses tested. these results are likely to suggest that toroviruses are widespread in the gdr and occur not only in horses but in other domestic animals and in man, as well. | 1990 | 2386426 |
| the carboxyl-terminal part of the putative berne virus polymerase is expressed by ribosomal frameshifting and contains sequence motifs which indicate that toro- and coronaviruses are evolutionarily related. | sequence analysis of the 3' part (8 kb) of the polymerase gene of the torovirus prototype berne virus (bev) revealed that this area contains at least two open reading frames (provisionally designated orf1a and orf1b) which overlap by 12 nucleotides. the complete sequence of orf1b (6873 nucleotides) was determined. like the coronaviruses, bev was shown to express its orf1b by ribosomal frameshifting during translation of the genomic rna. the predicted tertiary rna structure (a pseudoknot) in the ... | 1990 | 2388833 |
| preliminary characterisation of torovirus-like particles of humans: comparison with berne virus of horses and breda virus of calves. | pleomorphic virus-like particles have been observed by electron microscopy in the faeces of children and adults with diarrhoea. some of these particles were approximately 100 nm in diameter and had a "fringe" of closely applied peplomers approximately 10 nm long; they closely resembled berne virus of horses and breda virus of calves, the two representatives of a newly proposed family called the toroviridae. in one sample a toroidal nucleoprotein-like structure was observed within the particles. ... | 1986 | 3093635 |
| porcine torovirus? | | 1987 | 3113037 |
| toroviridae: a proposed new family of enveloped rna viruses. | the proposed family toroviridae is characterized by enveloped, peplomer-bearing particles containing an elongated tubular nucleocapsid of helical symmetry. the capsid may be bent into an open torus, conferring a biconcave disk or kidney shape on the virion (largest diameter 120-140 nm), or straight, resulting in a rod-shaped particle (dimensions 35 x 170 nm). morphogenesis occurs by the budding of preformed tubular nucleocapsids through membranes of the golgi system and of the rough endoplasmic ... | 1987 | 3595325 |
| a new family of vertebrate viruses: toroviridae. | the proposed family toroviridae is characterized by eveloped, peplomer-bearing particles containing an elongated tubular nucleocapsid with helical symmetry. the capsid may bend into an open torus, conferring a biconcave disk or kidney-shaped morphology to the virion (largest diameter 120-140 nm) or the capsid may be straight, resulting in a rod-shaped particle (35 x 170 nm). morphogenesis is by budding of preformed nucleocapsids through membranes mainly of the golgi system and of the rough endop ... | 1987 | 3610570 |
| snowdon lecture 1993. new virus diseases: visible evolution. | | 1993 | 8117207 |
| toroviruses of animals and humans: a review. | | 1994 | 8191955 |
| revision of the taxonomy of the coronavirus, torovirus and arterivirus genera. | | 1994 | 8198447 |
| the coronaviruslike superfamily. | | 1993 | 8209737 |
| the coronaviridae now comprises two genera, coronavirus and torovirus: report of the coronaviridae study group. | at the april 1992, mid-term meeting of the international committee on taxonomy of viruses (ictv) a proposal from the coronaviridae study group (csg) to include the torovirus genus in the coronaviridae was accepted. following another proposal, the arterivirus genus was removed from the togaviridae but not assigned to another family. the arteriviruses have some features in common with the coronaviridae but also have major differences. after much debate, culminating in september 1992, it was decide ... | 1993 | 8209739 |
| toroviruses--members of the coronavirus superfamily? | | 1993 | 8219815 |
| toroviruses: replication, evolution and comparison with other members of the coronavirus-like superfamily. | | 1993 | 8245847 |
| enzyme-linked immunosorbent assay reactivity of torovirus-like particles in fecal specimens from humans with diarrhea. | toroviruses are recognized enteric pathogens of cattle and horses; in humans, similar pleomorphic particles have been described, but doubt has been raised concerning their identity as viruses. we screened fecal samples from humans with diarrhea for the presence of torovirus-like particles (tvlps) by electron microscopy and subsequently used an enzyme-linked immunosorbent assay (elisa) with bovine torovirus reference reagents to test for the presence of torovirus antigens. to add another selectio ... | 1993 | 8253975 |
| genus torovirus assigned to the coronaviridae. | | 1993 | 8382042 |
| complete genomic sequence and phylogenetic analysis of the lactate dehydrogenase-elevating virus (ldv). | the apparently complete sequence of the rna genome of the neurovirulent isolate of lactate dehydrogenase-elevating virus (ldv-c) has been determined. the ldv-c genome is at least 14,222 nucleotides in length and contains eight open reading frames (orfs). orf 1a, which encodes a protein of 242.8 kda and is located at the 5' end of the genome, contains at least two putative papain-like cysteine protease domains, and one putative chymotrypsin-like serine protease domain. this orf terminates with a ... | 1993 | 8389075 |
| optimization of extraction and pcr amplification of rna extracts from paraffin-embedded tissue in different fixatives. | a method was developed for fast and efficient isolation of rna from paraffin-embedded tissue sections for subsequent pcr analysis. this method is based on the binding of rna to acid-treated glass beads in the presence of a high molarity of guanidinium salt. it can be completed within an hour, and obviates the need for dewaxing and phenol/chloroform extractions. the effect of various fixatives and fixation times was tested and the amplification of actin mrna fragments ranging in length from 82 to ... | 1993 | 8396155 |
| breda virus-like particles in calves in south africa. | | 1993 | 8410941 |
| an in-depth study of crohn's disease in two french families. | two french families were investigated. in the first a husband, wife, and 4 children had crohn's disease; in the second 7 of 11 children had the disease. there was no history of crohn's disease in antecedent generations and no linkage to hla haplotypes. | 1993 | 8425677 |
| lelystad virus, the causative agent of porcine epidemic abortion and respiratory syndrome (pears), is related to ldv and eav. | the genome of lelystad virus (lv), the causative agent of porcine epidemic abortion and respiratory syndrome (previously known as mystery swine disease), was shown to be a polyadenylated rna molecule. the nucleotide sequence of the lv genome was determined from a set of overlapping cdna clones. a consecutive sequence of 15,088 nucleotides was obtained. eight open reading frames (orfs) that might encode virus-specific proteins were identified. orf1a and orf1b are predicted to encode the viral rna ... | 1993 | 8517032 |
| faecal viruses of dogs--an electron microscope study. | faecal samples from 112 dogs both with and without diarrhoea were screened for parvovirus by a haemagglutination titration test and then examined by electron microscopy for the presence of viruses and virus-like particles. on the basis of morphology eight distinct viruses or virus-like particles were identified. particles identified were coronaviruses, coronavirus-like particles, rotavirus-like particles, papovavirus-like particles, torovirus-like particles, picornavirus-like particles, 27 nm vi ... | 1995 | 8545969 |
| evidence of torovirus infection in diarrhoeic cattle. | | 1996 | 8711886 |
| electronmicroscopic evidence of torovirus like particles in children with diarrhoea. | pleomorphic virus-like particles approximately 90 nm in diameter with short fringe (7-9 nm long) were observed in faecal specimens of two diarrhoeic children in the course of routine screening of samples for viruses by electronmicroscopy. no other viral, bacterial or parasitic pathogens were detected in the same samples. immune electronmicroscopic examination showed that these virus like particles were agglutinated by immunesera raised against breda i and breda ii viruses of calves. this observa ... | 1997 | 9119415 |
| association of torovirus with acute and persistent diarrhea in children. | to study the etiologic role of toroviruses as a cause of gastroenteritis in humans. | 1997 | 9154546 |
| hemagglutinin-esterase, a novel structural protein of torovirus. | we have characterized the 3'-most 3 kb of the genome of bovine torovirus (botv) strain breda. a novel 1.2-kb gene, located between the genes for the membrane and nucleocapsid proteins, was identified. this gene, the 3'-most 0.5 kb of which is also present in the genome of the equine torovirus isolate berne virus (bev), codes for a class i membrane protein displaying 30% sequence identity with the hemagglutinin-esterases (hes) of coronaviruses and influenza c viruses. heterologous expression of t ... | 1997 | 9188596 |
| pestiviruses--taxonomic perspectives. | the history of pestivirus taxonomy is surprisingly consistent: almost 30 years ago it was recognized that pestiviruses are structurally akin to flaviviruses, and recent nucleotide sequence data have confirmed this resemblance at the level of genome organization. for other enveloped positive stranded rna viruses with ikosahedral nucleocapsids e.g. equine arteritis and lactate dehydrogenase virus of mice a taxonomic dilemma is encountered; while virions resemble ("non-arthropod-borne") togaviruses ... | 1991 | 9210920 |
| characterization of torovirus from human fecal specimens. | the toroviruses, berne virus (bev) and breda virus (brv), are recognized pathogens of horses and cattle, respectively. torovirus-like particles (tvlps) that are immunologically related to brv have been reported as etiological agents of gastroenteritis in humans. of the toroviruses, only bev has been shown to replicate in cell culture. hence, these agents can be routinely detected only by electron microscopy (em), although serological testing has been used as well. our studies have provided suppo ... | 1997 | 9426455 |
| infectious agents associated with diarrhoea of calves in the canton of tilarán, costa rica. | a case-control study of calves under 3 months of age was carried out by weekly visits to 15 farms in the canton of tilarán, costa rica. most farms were dedicated to beef or dual-purpose (dp) production. faecal samples were collected over a 6-month period from a total of 194 calves with clinical signs and from 186 animals without clinical signs of diarrhoea as assessed by a scoring system. the samples were investigated for the presence of viruses, bacteria and parasites. torovirus was detected fo ... | 1998 | 9500174 |
| identification and characterization of a porcine torovirus. | a porcine torovirus (potv) was identified and characterized; it is a novel member of the genus torovirus (family coronaviridae, order nidovirales), closely related to but clearly distinct from the already recognized equine torovirus (etv) and bovine torovirus (botv) representatives. immunoelectron microscopy of feces from piglets revealed elongated, 120- by 55-nm particles which were recognized by a torovirus-specific antiserum. amplification by reverse transcriptase (rt) pcr with primers design ... | 1998 | 9557628 |
| detection of bovine torovirus in fecal specimens of calves with diarrhea from ontario farms. | breda virus (brv), a member of the genus torovirus, is an established etiological agent of disease in cattle. brv isolates have been detected in the stools of neonatal calves with diarrhea in both iowa and ohio and in several areas of europe. however, this virus has been reported only once in canada. therefore, a study was performed to determine the extent to which bovine torovirus is present in calves with diarrhea from farms in southern ontario. a total of 118 fecal samples from symptomatic ca ... | 1998 | 9574689 |
| cell culture-grown putative bovine respiratory torovirus identified as a coronavirus. | a putative bovine respiratory torovirus (brtv) was propagated in bovine fetal diploid lung and human colonic tumour cells, and fringed pleomorphic particles were detected in the culture supernatants by electron microscopy. antisera directed against a bovine (breda strain) and equine (berne strain) torovirus failed to react with brtv-infected cells in immunofluorescence assays and did not neutralise brtv. no toroviral rna was found in the supernatants of infected cells by means of a reverse trans ... | 1998 | 9670455 |
| human torovirus: a new nosocomial gastrointestinal pathogen. | studies were undertaken to determine if human torovirus is associated with gastroenteritis and to examine the clinical features of torovirus illness in children. the fecal excretion of torovirus in patients with gastroenteritis was compared with that in matched asymptomatic controls in a case-control study. toroviruses were identified in 72 (35.0%) of 206 gastroenteritis cases compared with 30 (14.5%) of 206 controls (p<.001). clinical features of torovirus gastroenteritis in 172 patients positi ... | 1998 | 9780245 |
| bovine torovirus: sequencing of the structural genes and expression of the nucleocapsid protein of breda virus. | breda virus (brv), a member of the genus torovirus, is an established etiological agent of diarrhea of cattle, which is found as two separate serotypes, brv-1 and brv-2. in this study, a 7.5 kb fragment of the brv-1 genome that bracketed the genes for the structural proteins of brv was amplified by long rt-pcr and the amplicon purified and sequenced directly. sequence analysis revealed the presence of four open reading frames (orf) corresponding to the peplomer (s), envelope (m), and nucleocapsi ... | 1998 | 9879765 |
| the novel hemagglutinin-esterase genes of human torovirus and breda virus. | human torovirus (htv) and breda virus (brv), members of the genus torovirus in the family coronaviridae, are established infectious agents of humans and cattle, respectively. the hemagglutinin-esterase (he) gene of breda virus serotype 2 (brv-2) has been identified and the nucleotide sequence for brv serotype 1 (brv-1) genome which contains the open reading frames for the viral structural proteins has been reported revealing the presence of a 1. 25 kb gene whose nucleotide sequence is identical ... | 1999 | 10518710 |
| molecular evolution of corona- and toroviruses. | | 1999 | 10659344 |
| torovirus gastroenteritis presenting as acute abdomen. | | 1999 | 10825073 |
| etiology of community-acquired pediatric viral diarrhea: a prospective longitudinal study in hospitals, emergency departments, pediatric practices and child care centers during the winter rotavirus outbreak, 1997 to 1998. the pediatric rotavirus epidemiology study for immunization study group. | to determine the viral etiology of community-acquired diarrhea in children admitted to hospitals and presenting in emergency departments, pediatric practices and child care centers from november 1, 1997, to june 30, 1998. | 2000 | 11001107 |
| [emergent riboviruses implicated in gastroenteritis]. | viral agents are one of the main causes of acute diarrhea, particularly in infants and young children. astrovirus, coronavirus, torovirus, and picobirnavirus are increasingly being identified as causative agents of gastroenteritis. astroviruses have been detected in the stools of between 1.2% and 20% of children with diarrhea requiring medical care in a variety of geographical areas. outbreaks have been described in schools, day care settings and pediatric wards. children younger than 3 years ol ... | 2001 | 11181210 |
| enteric infections with coronaviruses and toroviruses. | many enteric viruses are difficult or impossible to propagate in tissue culture. coronaviruses and toroviruses are large, enveloped, plus-strand rna viruses in the order nidovirales that cause enteric disease in young pigs, cows, dogs, mice, cats and horses. two different serogroups of mammalian coronaviruses cause frequent respiratory infections in humans, and coronaviruses and toroviruses have been implicated in human diarrhoeal disease by immunoelectron microscopy. however, there is as yet no ... | 2001 | 11444030 |
| gastroenteritis viruses: an overview. | acute gastroenteritis is among the most common illnesses of humankind, and its associated morbidity and mortality are greatest among those at the extremes of age, children and the elderly. in developing countries, gastroenteritis is a common cause of death in children < 5 years that can be linked to a wide variety of pathogens. in developed countries, while deaths from diarrhoea are less common, much illness leads to hospitalization or doctor visits. much of the gastroenteritis in children is ca ... | 2001 | 11444035 |
| notice of retraction to "the novel hemagglutinin-esterase genes of human torovirus and breda virus". [virus research 64 (1999) 137-149]. | | 2001 | 11682139 |
| enteric and nasal shedding of bovine torovirus (breda virus) in feedlot cattle. | to assess fecal and nasal shedding patterns of bovine torovirus (botv) in cattle at time of arrival and periodically throughout the first 21 days after arrival at a feedlot. | 2002 | 11911568 |
| torovirus detection in faecal specimens of calves and pigs in hungary: short communication. | bovine torovirus is an established aetiological agent of disease in cattle, while porcine torovirus has only been isolated from healthy animals. evidence for the presence of torovirus has been described in several european countries and also in the united states. a survey was performed to detect toroviruses in hungary by means of sampling ten swine and nine bovine herds. rectal swabs and faecal specimens were collected from diarrhoeic calves and from weaned piglets. the samples were tested by th ... | 2002 | 12237970 |
| discontinuous and non-discontinuous subgenomic rna transcription in a nidovirus. | arteri-, corona-, toro- and roniviruses are evolutionarily related positive-strand rna viruses, united in the order nidovirales. the best studied nidoviruses, the corona- and arteriviruses, employ a unique transcription mechanism, which involves discontinuous rna synthesis, a process resembling similarity-assisted copy-choice rna recombination. during infection, multiple subgenomic (sg) mrnas are transcribed from a mirror set of sg negative-strand rna templates. the sg mrnas all possess a short ... | 2002 | 12456663 |
| comparison of elisa and rt-pcr versus immune electron microscopy for detection of bovine torovirus (breda virus) in calf fecal specimens. | bovine torovirus (botv) is an uncultivable enteric pathogen of cattle. its failure to grow in vitro limits epidemiological studies, characterization of the virus, and development of diagnostic techniques. the objectives of this study were to develop and standardize an antigen-capture enzyme-linked immunosorbent assay (elisa) and a reverse transcriptase-polymerase chain reaction (rt-pcr) assay for the detection of botv in fecal specimens. these assays were compared with immunoelectron microscopy ... | 2003 | 12661719 |
| viruses causing gastroenteritis. | acute gastroenteritis is one of the most common diseases in humans worldwide. viruses are recognized as important causes of this disease, particularly in children. since the norwalk virus was identified as a cause of gastroenteritis, the number of viral agents associated with diarrheal disease in humans has steadily increased. rotavirus is the most common cause of severe diarrhea in children under 5 years of age. astrovirus, calicivirus and enteric adenovirus are also important etiologic agents ... | 2003 | 12667234 |
| association of enteric shedding of bovine torovirus (breda virus) and other enteropathogens with diarrhea in veal calves. | to determine the prevalence, fecal shedding pattern, and association of bovine torovirus (botv) with diarrhea in veal calves at time of arrival and periodically throughout the first 35 days after their arrival on a veal farm. | 2003 | 12693541 |
| detection of bovine torovirus and other enteric pathogens in feces from diarrhea cases in cattle. | the objectives of this study were to determine the prevalence of bovine torovirus (botv) in bovine fecal samples from diarrhea cases submitted to the ohio animal disease diagnostic laboratory (addl) and to assess if a relationship exists between botv and the other enteric pathogens detected. from november 1999 to may 2001, 259 specimens from 53 calves (< or = 6 months old), 27 young adults (52 years), 125 adults (> or = 2 years), and 54 animals of unknown age were examined by an antigen-capture ... | 2003 | 12735342 |
| phylogenetic and evolutionary relationships among torovirus field variants: evidence for multiple intertypic recombination events. | toroviruses (family coronaviridae, order nidovirales) are enveloped, positive-stranded rna viruses that have been implicated in enteric disease in cattle and possibly in humans. despite their potential veterinary and clinical relevance, little is known about torovirus epidemiology and molecular genetics. here, we present the first study into the diversity among toroviruses currently present in european swine and cattle herds. comparative sequence analysis was performed focusing on the genes for ... | 2003 | 12915570 |
| unique and conserved features of genome and proteome of sars-coronavirus, an early split-off from the coronavirus group 2 lineage. | the genome organization and expression strategy of the newly identified severe acute respiratory syndrome coronavirus (sars-cov) were predicted using recently published genome sequences. fourteen putative open reading frames were identified, 12 of which were predicted to be expressed from a nested set of eight subgenomic mrnas. the synthesis of these mrnas in sars-cov-infected cells was confirmed experimentally. the 4382- and 7073 amino acid residue sars-cov replicase polyproteins are predicted ... | 2003 | 12927536 |
| a comparative sequence analysis to revise the current taxonomy of the family coronaviridae. | the coronaviridae family, comprising the coronavirus and torovirus genera, is part of the nidovirales order that also includes two other families, arteriviridae and roniviridae. based on genetic and serological relationships, groups 1, 2 and 3 were previously recognized in the coronavirus genus. in this report we present results of comparative sequence analysis of the spike (s), envelope (e), membrane (m), and nucleoprotein (n) structural proteins, and the two most conserved replicase domains, p ... | 2003 | 14579179 |
| nidovirus sialate-o-acetylesterases: evolution and substrate specificity of coronaviral and toroviral receptor-destroying enzymes. | many viruses achieve reversible attachment to sialic acid (sia) by encoding envelope glycoproteins with receptor-binding and receptor-destroying activities. toroviruses and group 2 coronaviruses bind to o-acetylated sias, presumably via their spike proteins (s), whereas other glycoproteins, the hemagglutinin-esterases (he), destroy sia receptors by de-o-acetylation. here, we present a comprehensive study of these enzymes. sialate-9-o-acetylesterases specific for 5-n-acetyl-9-o-acetylneuraminic a ... | 2005 | 15507445 |
| viruses that multiply in the gut and cause endemic and epidemic gastroenteritis. | acute infectious diarrhea in young children is a leading cause of morbidity and mortality in developing countries. even in developed countries, infectious enteritis is second only to respiratory infections as a cause of morbidity in early childhood. | 1996 | 15566895 |
| coronavirus genome structure and replication. | in addition to the sars coronavirus (treated separately elsewhere in this volume), the complete genome sequences of six species in the coronavirus genus of the coronavirus family [avian infectious bronchitis virus-beaudette strain (ibv-beaudette), bovine coronavirus-ent strain (bcov-ent), human coronavirus-229e strain (hcov-229e), murine hepatitis virus-a59 strain (mhv-a59), porcine transmissible gastroenteritis-purdue 115 strain (tgev-purdue 115), and porcine epidemic diarrhea virus-cv777 strai ... | 2005 | 15609507 |
| torovirus non-discontinuous transcription: mutational analysis of a subgenomic mrna promoter. | toroviruses (order nidovirales) are enveloped positive-strand rna viruses of mammals. the prototype torovirus, equine torovirus strain berne (berne virus [bev]), uses two different transcription strategies to produce a 3'-coterminal nested set of subgenomic (sg) mrnas. its mrna 2 carries a leader sequence derived from the 5' end of the genome and is produced via discontinuous transcription. the remaining three sg mrnas, 3 to 5, are colinear with the 3' end of the genome and are made via non-disc ... | 2005 | 15956573 |
| bovine torovirus (breda virus) revisited. | bovine torovirus (botv) is a pleomorphic virus with a spike-bearing envelope and a linear, non-segmented, positive-sense single-stranded rna genome. this kidney-shaped virus is associated with diarrhea in calves and apparently has a worldwide distribution. this review provides details of the history and taxonomy of botv since its discovery in 1979. information about virion morphology and architecture, antigenic and biological properties, viral genome, protein composition, thermal and chemical st ... | 2004 | 15984322 |
| a survey for torovirus in new zealand cats with protruding nictitating membranes. | faecal samples from 51 cats were examined by negative stain electron microscopy to investigate a possible association between the syndrome of bilateral protrusion of the nictitating membranes and torovirus infection. although toroviruses were not observed in any sample, other viruses or virus-like particles were observed in faeces from one of 15 cats with the syndrome, six of 21 cats which had experienced prior episodes of the syndrome and four of 15 healthy control cats. the findings of this st ... | 1997 | 16031947 |
| the complete sequence of the bovine torovirus genome. | viruses in the family coronaviridae have elicited new interest, with the outbreaks caused by sars-hcov in 2003 and the recent discovery of a new human coronavirus, hcov-nl63. the genus torovirus, within the family coronaviridae, is less well characterized, in part because toroviruses cannot yet be grown in cell culture (except for the berne virus). in this study, we determined the sequence of the complete genome of breda-1 (botv-1), a bovine torovirus. this is the first complete torovirus genome ... | 2006 | 16137782 |
| human torovirus: a new virus associated with neonatal necrotizing enterocolitis. | toroviruses have been associated with gastroenteritis in both animals and humans. the aim of this study was to examine the fecal excretion of torovirus in infants with necrotizing enterocolitis (nec). | 2005 | 16188853 |
| characterization of a torovirus main proteinase. | viruses of the order nidovirales encode huge replicase polyproteins. these are processed primarily by the chymotrypsin-like main proteinases (m(pro)s). so far, m(pro)s have been studied only for corona-, arteri-, and roniviruses. here, we report the characterization of the m(pro) of toroviruses, the fourth main nidovirus branch. comparative sequence analysis of polyprotein 1a of equine torovirus (etov) strain berne, identified a serine proteinase domain, flanked by hydrophobic regions. heterolog ... | 2006 | 16571831 |
| structure, function and evolution of the hemagglutinin-esterase proteins of corona- and toroviruses. | virus attachment to host cells is mediated by dedicated virion proteins, which specifically recognize one or, at most, a limited number of cell surface molecules. receptor binding often involves protein-protein interactions, but carbohydrates may serve as receptor determinants as well. in fact, many different viruses use members of the sialic acid family either as their main receptor or as an initial attachment factor. sialic acids (sias) are 9-carbon negatively-charged monosaccharides commonly ... | 2006 | 16575523 |
| detection of bovine torovirus in neonatal calf diarrhoea in lower austria and styria (austria). | faeces of 230 calves with and without diarrhoea collected during the winter period 2004/2005 in 100 austrian farms (styria and lower austria) were examined for viral, bacterial and parasitic enteropathogens. torovirus-specific nucleic acid confirmed by reverse transcriptase-polymerase chain reaction was found in 12 of 230 calves (5.2%). ten of these calves were clinically ill, several of them showing signs of dehydration and abnormal faecal consistency at the time of sampling. computer assisted ... | 2006 | 16629982 |
| nidovirus transcription: how to make sense...? | many positive-stranded rna viruses use subgenomic mrnas to express part of their genetic information. to produce structural and accessory proteins, members of the order nidovirales (corona-, toro-, arteri- and roniviruses) generate a 3' co-terminal nested set of at least three and often seven to nine mrnas. coronavirus and arterivirus subgenomic transcripts are not only 3' co-terminal but also contain a common 5' leader sequence, which is derived from the genomic 5' end. their synthesis involves ... | 2006 | 16690906 |
| characterization of white bream virus reveals a novel genetic cluster of nidoviruses. | the order nidovirales comprises viruses from the families coronaviridae (genera coronavirus and torovirus), roniviridae (genus okavirus), and arteriviridae (genus arterivirus). in this study, we characterized white bream virus (wbv), a bacilliform plus-strand rna virus isolated from fish. analysis of the nucleotide sequence, organization, and expression of the 26.6-kb genome provided conclusive evidence for a phylogenetic relationship between wbv and nidoviruses. the polycistronic genome of wbv ... | 2006 | 16987966 |
| new insights on the structure and morphogenesis of berne virus. | | 2006 | 17037526 |
| epidemiological analysis of bovine torovirus in japan. | bovine torovirus (btov), a member of the coronaviridae family, is an established gastrointestinal infectious agent in cattle. no epidemiological research on btov has been reported from japan. in this study, we performed a survey to detect btov in japan in 2004 and 2005 using 231 fecal samples (167 from diarrheic cattle and 64 from asymptomatic cattle) that were analyzed by nested reverse transcription (rt) pcr using primers located in the consensus sequences of the reported btov nucleocapsid (n) ... | 2007 | 17320234 |
| molecular epidemiology of bovine noroviruses in south korea. | since the prevalence of bovine norovirus (bnov) and their genetic diversity have only been reported in the usa, england, germany and the netherlands, this study examined the prevalence and genetic diversity of bnovs in diarrheic calves in south korea using 645 diarrheic fecal specimens from calves by rt-pcr and nested pcr assays. overall, 9.3% of the diarrheic fecal samples tested positive for bnovs by either rt-pcr or nested pcr, of which 5.9% samples also tested positive for other enteric path ... | 2007 | 17466472 |
| detection of bovine torovirus in fecal specimens of calves with diarrhea in japan. | the aim of this study was to determine the prevalence of bovine torovirus (botv) in bovine fecal samples and to determine whether a relationship exists between botv and diarrhea in japan. ninety-nine diarrheic and 114 normal fecal samples from calves in hokkaido prefecture and 38 diarrheic fecal samples from calves in 10 other prefectures were examined by reverse transcription (rt)-pcr with primers designed in the spike (s) gene for the presence of botv. the specimens were also examined for the ... | 2007 | 17551218 |
| antiviral activity of carbohydrate-binding agents against nidovirales in cell culture. | coronaviruses are important human and animal pathogens, the relevance of which increased due to the emergence of new human coronaviruses like sars-cov, hku1 and nl63. together with toroviruses, arteriviruses, and roniviruses the coronaviruses belong to the order nidovirales. so far antivirals are hardly available to combat infections with viruses of this order. therefore, various antiviral strategies to counter nidoviral infections are under evaluation. lectins, which bind to n-linked oligosacch ... | 2007 | 17560666 |
| first isolation of cytopathogenic bovine torovirus in cell culture from a calf with diarrhea. | a cytopathogenic virus (designated the aichi/2004 strain) was isolated in a human rectal adenocarcinoma cell line (hrt-18) from the ileum contents of a calf with diarrhea. oval and elongated particles, approximately 100 to 170 nm in diameter, with club-shaped projections were seen in the infected culture supernatant, and torovirus-like (tubular and torus nucleocapsid) structures were seen in the infected cells by electron microscopy. an antiserum against bovine torovirus (btov) reacted with the ... | 2007 | 17567770 |
| molecular epidemiology of bovine toroviruses circulating in south korea. | the prevalence of the bovine torovirus (btov) and its genetic characterization have been reported in north america, europe and japan. therefore, this study examined the prevalence and genetic diversity of the btov in a total of 645 diarrheic fecal samples from 629 korean native beef calf herds using rt-pcr and nested pcr with the primer pairs specific to a part of the btov membrane (m) gene. overall, 19 (2.9%) out of 645 diarrheic samples from 19 herds (6.9%) tested positive for btovs by either ... | 2008 | 17719729 |
| detection and characterization of bovine torovirus from the respiratory tract in japanese cattle. | bovine torovirus (btov), a member of the coronaviridae family, is a causative agent of diarrhea in cattle, but it may also possess tropism for the respiratory tract. however, no surveys concerning with the relation between respiratory symptoms and the detection of btov have been conducted in wide range. among 311 nasal samples, btov gene products were detected in seven samples (rbtov-1 to -7) derived only from calves with respiratory symptoms, suggesting that btov may be a predisposing factor an ... | 2009 | 19128894 |
| molecular characterization of a new ptov strain. evolutionary implications. | toroviruses are emergent viruses, belonging to the nidovirales order, that remain mostly ignored, despite they are able to infect different species of domestic animals and humans, causing enteric diseases and diarrhea. thus far, only five variants of porcine torovirus (ptov) have been identified. in this report we describe the identification and partial characterization of a new strain of porcine torovirus (ptov-bres) that was detected by rt-pcr in a swine faecal specimen from a farm in brescia ... | 2009 | 19463719 |
| structural basis for ligand and substrate recognition by torovirus hemagglutinin esterases. | hemagglutinin esterases (hes), closely related envelope glycoproteins in influenza c and corona- and toroviruses, mediate reversible attachment to o-acetylated sialic acids (sias). they do so by acting both as lectins and as receptor-destroying enzymes, functions exerted by separate protein domains. he divergence was accompanied by changes in quaternary structure and in receptor and substrate specificity. the selective forces underlying he diversity and the molecular basis for sia specificity ar ... | 2009 | 19721004 |
| a case for a cug-initiated coding sequence overlapping torovirus orf1a and encoding a novel 30 kda product. | the genus torovirus (order nidovirales) includes a number of species that infect livestock. these viruses have a linear positive-sense ssrna genome of approximately 25-30 kb, encoding a large polyprotein that is expressed from the genomic rna, and several additional proteins expressed from a nested set of 3'-coterminal subgenomic rnas. in this brief report, we describe the bioinformatic discovery of a new, apparently coding, orf that overlaps the 5' end of the polyprotein coding sequence, orf1a, ... | 2009 | 19737402 |
| detection of porcine torovirus by real time rt-pcr in piglets from a spanish farm. | toroviruses are enteric viruses belonging to the nidovirales order that infect different animal species and humans. the lack of "in vitro" culture systems for toroviruses, except for the prototype berne virus or bev, isolated originally from an infected horse, has hampered their study and the development of diagnostic assays. this report describes a real time rt-pcr method to detect porcine torovirus (ptov) rna in clinical fecal samples using primers corresponding to the gene coding for the nucl ... | 2010 | 19887084 |
| detection and molecular characterization of porcine toroviruses in korea. | this study examined the prevalence and genetic diversity of the porcine torovirus (ptov) in korea. of 295 samples, 19 (6.4%) samples tested positive for ptovs by rt-pcr. a low nucleotide sequence identity of the partial s gene was detected among the korean ptovs (73.5%) and between the korean and european ptovs (74.0%). phylogenetic analysis of the spike and nucleocapsid genes showed that the korean ptovs form distinct branches with clusters corresponding to the farm of origin, which were separa ... | 2010 | 20127374 |
| genetic and antigenic characterization of newly isolated bovine toroviruses from japanese cattle. | torovirus, a member of the coronaviridae family, is a gastrointestinal infectious agent that has been identified in humans, cattle, pigs, and equines. toroviruses, except equine torovirus, are difficult to propagate in cell culture; indeed, to date, only the aichi/2004 strain of bovine torovirus (btov) has been isolated among the human, bovine, and porcine toroviruses. in the present study, four cytopathogenic btovs were isolated from diarrheal feces of the cattle using the hrt-18 cell line, and ... | 2010 | 20220164 |
| structural and functional analysis of the hemagglutinin-esterase of infectious salmon anaemia virus. | infectious salmon anaemia virus (isav) is a piscine orthomyxovirus causing a serious disease in farmed atlantic salmon (salmo salar l.). the virus surface glycoprotein hemagglutinin-esterase (he) is responsible for both viral attachment and release. similarity to bovine and porcine torovirus hemagglutinin-esterase (btov he, ptov he), bovine coronavirus he (bcov he) and influenza c hemagglutinin-esterase-fusion (infc hef) proteins were exploited in a computational homology-based structure analysi ... | 2010 | 20398710 |
| longitudinal serological and virological study on porcine torovirus (ptov) in piglets from spanish farms. | a study was performed to evaluate porcine torovirus (ptov) seroprevalence and infection in three multi-site farms from the north-eastern region of spain. serum samples from 120 piglets and faecal samples from 36 piglets were longitudinally collected at 1, 3, 7, 11 and 15 weeks of age. serum samples from their dams (n=30) were also taken 1-week post-farrowing. ptov antibodies in serum were monitored by elisa, while viral infection was assessed by real-time rt-pcr in faeces. a high seroprevalence ... | 2010 | 20542392 |
| development of universal sybr green real-time rt-pcr for the rapid detection and quantitation of bovine and porcine toroviruses. | toroviruses (tovs) are a group of emerging viruses that cause gastroenteritis in domestic animals and humans. currently, methods such as real-time reverse transcription-polymerase chain reaction (real-time rt-pcr) have not yet been developed for the rapid detection and quantitation of bovine (btov) and porcine (ptov) toroviruses. using btov and ptov rna standards generated by in vitro transcription, the detection limit of the sybr green real-time rt-pcr assay was 2.54 x 10(2) btov and 2.17 x 10( ... | 2010 | 20558206 |
| equine torovirus (bev) induces caspase-mediated apoptosis in infected cells. | toroviruses are gastroenteritis causing agents that infect different animal species and humans. to date, very little is known about how toroviruses cause disease. here, we describe for the first time that the prototype member of this genus, the equine torovirus berne virus (bev), induces apoptosis in infected cells at late times postinfection. observation of bev infected cells by electron microscopy revealed that by 24 hours postinfection some cells exhibited morphological characteristics of apo ... | 2011 | 21698249 |
| [viral gastroenteritis in domestic animals and zoonoses]. | etiologic investigations of infectious diarrhea were long limited to bacteria and protozoa. the advent of electron microscopy and molecular biology showed that diarrhea could also be caused by viruses, both in humans and in other animals. in 1969, electron microcopy was used to show, for the first time, the responsibility of a virus in a case of calf diarrhea. this "reo-like virus "was subsequently identified as a rotavirus, and was shown only four years later to be responsible for severe diarrh ... | 2010 | 22046708 |
| Design and validation of consensus-degenerate hybrid oligonucleotide primers for broad and sensitive detection of corona- and toroviruses. | The ssRNA+ family Coronaviridae includes two subfamilies prototyped by coronaviruses and toroviruses that cause respiratory and enteric infections. To facilitate the identification of new distantly related members of the family Coronaviridae, we have developed a molecular assay with broad specificity. The consensus-degenerated hybrid oligonucleotide primer (CODEHOP) strategy was modified to design primers targeting the most conserved motifs in the RNA-dependent RNA polymerase locus. They were ev ... | 2011 | 21864579 |
| Characterization of epidemic diarrhea outbreaks associated with bovine torovirus in adult cows. | Bovine torovirus (BToV) is recognized as an enteric pathogen of calves, but its etiological role in diarrhea and epidemiological characterization in adult cows remain unclear. In 2007-2008, three outbreaks of epidemic diarrhea occurred in adult cows at three dairy farms in Niigata Prefecture, Japan. BToV was the only enteric pathogen detected in these outbreaks, as determined by electron microscopy, reverse transcription-PCR, bacteria and parasite tests of fecal samples, and antibody tests with ... | 2011 | 22167249 |
| [epidemiology of viral gastroenteritis in france and europe]. | continuous surveillance of acute diarrhea in france has been conducted by inserm's sentinel network of general practitioners (gp) since 1991. similar gp-based studies have been performed in the netherlands, austria and the uk. the causes of most cases of acute diarrhea are unclear. in case-controlstudies designed to identify viruses in stools, 35 to 40% of cases and virtually none of the controls were positive for one of 4 major viruses (rotavirus, calicivirus, astrovirus and adenovirus). thus, ... | 2010 | 22046706 |