| ophthalmic lesions and dacryoadenitis: a naturally occurring aspect of sialodacryoadenitis virus infection of the laboratory rat. | | 1977 | 198605 |
| respiratory infection in mice with sialodacryoadenitis virus, a coronavirus of rats. | sialodacryoadenitis virus (sdav), a coronavirus of rats, evoked both serum neutralization and complement fixation antibody responses when inoculated intranasally in mice. weanling gnotobiotic cd-1 mice inoculated intranasally with 10(3.0) mean tissue culture infective doses of sdav remained asymptomatic. virus was recovered from the nasopharynx, trachea, and lung from day 2 to day 7. viral antigen was readily detected by indirect immunofluorescence in the lung but rarely in the nasopharynx. infe ... | 1977 | 201568 |
| harderian gland dacryoadenitis in rats resulting from orbital bleeding. | localized necrotizing inflammation of the harderian gland was a sequela to obtaining blood samples from rats by the orbital bleeding technique. the lesion affected a few adjoining lobules that were adjacent to ocular muscles, in contrast to the widespread inflammation of the harderian gland which results from sialodacryoadenitis virus infection. lesions resolved in 4 weeks by atrophy of acini in affected lobules with associated mononuclear cell inflammation and fibrosis. | 1979 | 513634 |
| ulcerative dermatitis in the rat. | ulcerative dermatitis observed in several shipments of rats was found to be limited to one strain (sprague dawley) provided by one supplier from two specific breeding areas. the incidence of lesions was higher in males than in females. rats receiving an agar base diet also appeared to have a higher incidence of the lesions. the lesion consisted of a moist ulcer usually involving the lateral aspect of the shoulder and often the sides of the neck. staphylococcus aureus was isolated from lesions of ... | 1977 | 592722 |
| keratoconjunctivitis associated with sialodacryoadenitis in rats. | a high incidence of keratoconjunctivitis was observed in a closed colony of inbred lewis/wistar rats. clinical signs including blinking, ocular discharge, circumcorneal flush, corneal opacity, ulceration, pannus, hypopyon, and hyphema were observed at about three weeks of age. acute disease subsided by six weeks of age, but some lesions progressed to low-grade chronic keratitis. six per cent of affected rats developed megaloglobus, which usually appeared by three weeks of age. lesions included f ... | 1976 | 931700 |
| transmission of sialodacryoadenitis virus (sdav) from infected rats to rats and mice through handling, close contact, and soiled bedding. | thirty mice and six rats were exposed through handling, soiled bedding, or close contact to rats previously inoculated with sialodacryoadenitis virus (sdav). all exposed rats developed coronaviral antibody without clinical signs or lesions of sdav infection. exposed mice had no lesions or clinical signs of coronavirus infection. mice exposed by handling or by soiled bedding did not develop coronavirus antibody. two of 10 mice exposed to sdav-inoculated rats by close contact were coronavirus sero ... | 1992 | 1331604 |
| pulmonary clearance of mycoplasma pulmonis in rats with respiratory viral infections or of susceptible genotype. | we sought to determine whether or not increased severity of bronchopulmonary disease due to mycoplasma pulmonis infection in rats with respiratory viral infections and in rats of susceptible genotype could result from altered pulmonary clearance. pathogen-free rats were exposed to aerosols of radiolabeled m. pulmonis and the numbers of m. pulmonis colony-forming units, and amounts of radiolabel in the lungs were determined immediately after exposure or 4 hours later. intrapulmonary killing of m. ... | 1992 | 1460843 |
| experimental sialodacryoadenitis virus infection in severe combined immunodeficient mice. | mice with a severe combined immunodeficiency in b and t lymphocytes and natural killer cells (scid-beige) were inoculated intranasally with sialodacryoadenitis (sda) virus, a coronavirus of rats. animals were killed at designated intervals and tissues were examined for evidence of viral infection by light microscopy and immunofluorescence microscopy. based on these criteria, there was no evidence that these immunodeficient mice were susceptible to infection with sda virus. | 1991 | 1653101 |
| reproductive disorders in female rats infected with sialodacryoadenitis virus. | effects of sialodacryoadenitis virus infection on the reproduction of wistar and sprague-dawley (sd) rats were studied. estrous cycle was considerably out of order in about 40% of infected rats of both strains, starting on days 4 to 20 postinfection and persisting for 2 to 12 days. of wistar and sd dams infected on day 0 of gestation about 30% and 10% of the fetuses were found dead, while only 4 and 3% of non-infected dams. in severely diseased wistar and sd dams infected on day 15 of gestation, ... | 1991 | 1655499 |
| detection of rodent coronaviruses in tissues and cell cultures by using polymerase chain reaction. | a polymerase chain reaction (pcr) method was developed for the detection of rodent coronaviruses in biological material by using reverse transcriptase and two primers which flanked an m gene sequence of 375 bp. pcr detected all of 11 different strains of mouse hepatitis virus (mhv) as well as rat sialodacryoadenitis virus but not bovine coronavirus or human coronavirus strains oc43 and 229e. the m gene sequences of bovine coronavirus and human coronavirus oc43 are homologous to that of mhv, but ... | 1991 | 1661745 |
| lack of effects of viral sialoadenitis and depletion of epidermal growth factor on initiation of hepatic carcinogenesis in the rat. | sialodacryoadenitis (sda) is a commonly-encountered coronaviral infection in laboratory rats that causes acute destruction of submandibular salivary glands. sda results in depletion of salivary epidermal growth factor (egf) and may thereby affect egf-dependent cell growth processes. the purpose of this study was to determine the effects of sda virus (sdav) infection on the growth factor-dependent stages of experimental liver carcinogenesis. rats were injected ip with the carcinogen diethylnitros ... | 1991 | 1663270 |
| antigenic heterogeneity of sialodacryoadenitis virus isolates. | seventeen field isolates of sialodacryoadenitis (sda) virus had been isolated from the lung of rats with clinical sda during epizootics of sda from 1976 to 1978 in the research laboratory. based on their neutralization patterns against antisera to strains 681, 930-10, lu-3, lu-4 and lu-7, these isolates were divided into 3 antigenic groups. the first group consisted of 8 isolates which were neutralized by 4 out of 5 antisera at high serum dilution. the second group consisted of 6 isolates which ... | 1991 | 1665081 |
| chronic sialodacryoadenitis virus (sdav) infection in athymic rats. | sialodacryoadenitis virus (sdav) was detected in athymic rats subcutaneously implanted with human tumor cell lines. clinical signs included sneezing, dyspnea, weight loss and death. necropsy revealed both upper and lower respiratory tract disease from which staphylococcus aureus, pasteurella pneumotropica and pseudomonas aeruginosa were recovered. histopathological changes consisted of suppurative rhinitis and bronchopneumonia. lesions characteristic of sdav infection were found in lacrimal and ... | 1991 | 1849581 |
| a comparison of the sensitivity and specificity of sialodacryoadenitis virus, parker's rat coronavirus, and mouse hepatitis virus-infected cells as a source of antigen for the detection of antibody to rat coronaviruses. | sialodacryoadenitis virus (sdav) and parker's rat coronavirus (prc) are two recognized viral strains which cause spontaneous disease in the laboratory rat. currently there is no recognized practical procedure which will accurately differentiate infections with these strains. using sdav- and prc-infected l-2 cells as the source of antigen, and sera from rats collected post inoculation with either of these viral strains, the indirect fluorescent antibody (ifa) procedure was used to determine wheth ... | 1991 | 1877886 |
| reproductive disorders in female shr rats infected with sialodacryoadenitis virus. | effects of sialodacryoadenitis virus infection on the reproduction of female shr rats were studied. the oestrous cycle was considerably perturbed in most infected rats, the perturbation was observed initially between days 0 to 10 post infection and the effect persisted for 6 to 18 days. about half of the foetuses of dams infected on day 0 of gestation were found dead while only 4% of the foetuses from non-infected dams were found dead. five or six days after infection on day 0 of gestation, some ... | 1990 | 1966445 |
| susceptibility of rodent cell lines to rat coronaviruses and differential enhancement by trypsin or deae-dextran. | cell lines of rodent origin were tested for susceptibility to infection with rat coronavirus (rcv), including sialodacryoadenitis virus (sdav) and parker's rat coronavirus (prcv). lbc rat mammary adenocarcinoma cells were susceptible only if the cells were treated with diethylaminoethyl-dextran (deae-d). a recent report that rcvs grow well in l2 mouse fibroblast cells was confirmed and expanded. rcv infection of l2 cells was substantially enhanced by treatment of cells with trypsin but not by tr ... | 1991 | 2048975 |
| studies on the development of an elisa kit for microbiological monitoring. 1. evaluation of the reliability of the prototype kit by field tests. | the prototype of an elisa kit using protein a as the second reaction reagent for mice and anti-rat igg for rats was prepared for seromonitoring of the sendai virus and mouse hepatitis virus (mhv)/sialodacryoadenitis virus (sdav)/parker's rat coronavirus (pcv) infections. the respective antigen strains and protein concentrations were sendai virus mn strain, 2 micrograms/ml and mhv nu-67 strain, 5 micrograms/ml. the reliability of this prototype kit was investigated in two field tests performed on ... | 1990 | 2154385 |
| persistence of sialodacryoadenitis virus in athymic rats. | to determine whether sdav infection persists in athymic rats, weanling athymic rats and euthymic rats were inoculated intranasally with 10(4) tcid50 of sdav and examined periodically for up to 90 days. viral antigen and lesions characteristic of acute sdav infection, including rhinotracheitis, bronchitis and sialodacryoadenitis, were detected in both groups of rats during the first week. in euthymic rats, tissues were under repair and viral antigen was undetectable by day 17, and tissues were hi ... | 1990 | 2157091 |
| duration of protection from reinfection following exposure to sialodacryoadenitis virus in wistar rats. | wistar rats [cr1:(wi)br] were inoculated intranasally with approximately 10(3) median mouse lethal infective doses of sialodacryoadenitis (sda) virus. animals were subsequently selected at random, removed to a separate isolation room, and reinfected with sda virus at 3, 6, 9, 12 or 15 months. pre- and postinoculation serum samples were collected from all animals during the course of the study and evaluated for antibody titers to sda virus. all experimental, control and sentinel animals, followin ... | 1990 | 2157092 |
| infection of sdav-immune rats with sdav and rat coronavirus. | infection of rats with sialodacryoadenitis virus (sdav) or rat coronavirus (rcv) is acute and self-limiting, and elimination and control of either virus is based on the assumption that recovered rats are immune to reinfection. to test this hypothesis, we examined whether sdav-immune rats could be infected with rcv or reinfected with sdav. sprague dawley (sd) rats were inoculated intranasally with sdav or with culture medium alone and serial sdav antibody titers were obtained. eleven months after ... | 1990 | 2166861 |
| susceptibility of laboratory mice to intranasal and contact infection with coronaviruses of other species. | the susceptibility of laboratory mice to intranasal and contact infection with mouse hepatitis virus (mhv)-related coronaviruses was tested in infant cd1 mice. one day old mouse pups were inoculated intranasally with respiratory mhv-s, enteric mhv-y, rat sialodacryoadenitis virus (sdav), human coronavirus oc43 (hcv-oc43) or bovine coronavirus (bcv). twenty-four hours later, they were placed in direct contact with age matched sham inoculated pups. indices of infection in virus inoculated mice inc ... | 1990 | 2170746 |
| plaque assay and propagation in rat cell line lbc cells of rat coronavirus and 5 strains of sialodacryoadenitis virus. | various factors influencing the plaque formation of rat coronavirus (rcv) and sialodacryoadenitis virus (sdav) in lbc cell monolayers were studied to develop the practical method for plaque assay. by this method, 4 japanese isolates of sdav also produced clear plaques. in one-step growth experiments of these viruses, newly formed virus was first recognized within 7.5 h postinfection and showed subsequently a rapid exponential increase. the virus was released rapidly from the infected cells. by i ... | 1990 | 2363328 |
| characteristics of parker's rat coronavirus (prc) replicated in l-2 cells. | parker's rat coronavirus (prc) is a naturally-occurring viral infection of the laboratory rat. on the first passage, atcc strain 8190 of prc replicated in l-2 cells. using the tenth passage of prc in l-2 cells, the characteristics of the virus were compared with previous studies of sialodacryoadenitis virus (sdav) replicated in l-2 cells. based on light and immunofluorescence microscopic examination of control and inoculated cell cultures, prc-associated cpe was frequently confined primarily to ... | 1990 | 2378568 |
| replication of sialodacryoadenitis virus in mouse l-2 cells. | sialodacryoadenitis (sda) is a naturally-occurring infection of the laboratory rat raused by the coronavirus, sialodacryoadenitis virus (sdav). the study of sdav has been limited because there is no widely available continuous cell line for the propagation of high titers of the virus. the purpose of this study, therefore, was to compare the ability of sdav to replicate in the permanent cell lines, lbc, of rat origin, and the mouse cell lines. l-929 and l-2. following 2 to 6 repeated passages of ... | 1989 | 2539798 |
| sequential changes in the harderian and exorbital lacrimal glands in wistar rats infected with sialodacryoadenitis virus. | a sequential light and electron microscopic study of the exorbital and harderian lacrimal glands was done on 2.5- to 15-month-old wistar rats exposed to sialodacryoadenitis (sda) virus. typical coronaviral particles were readily demonstrated in cytoplasmic vesicles of harderian and exorbital glands examined at 6 days post-inoculation. lesions were seen in a relatively high percentage of lacrimal glands in infected animals of all ages, with no obvious age-related variations in the incidence and e ... | 1989 | 2548316 |
| influence of viral infections on body weight, survival, and tumor prevalence in fischer 344/ncr rats on two-year studies. | sendai virus (sv), pneumonia virus of mice (pvm), and rat coronavirus/sialodacryoadenitis virus (rcv/sdav) were common viral infections of rats in the national cancer institute-national toxicology program (nci-ntp) studies from 1977 to 1983. influence of these viral infections on body weight, survival, and prevalences of spontaneous tumors in the f344/ncr rats of 28 diet control groups at five different laboratories were evaluated. tumor prevalences evaluated in this investigation included the f ... | 1989 | 2554057 |
| exacerbation of murine respiratory mycoplasmosis by sialodacryoadenitis virus infection in gnotobiotic f344 rats. | to test the hypothesis that sialodacryoadenitis virus infection could exacerbate respiratory mycoplasmosis in rats, four groups of 40 7- to 9-week-old gnotobiotic f344/n rats were given two intranasal inoculations 7 days apart: mycoplasma pulmonis, then sialodacryoadenitis virus; m. pulmonis followed by sterile culture medium; medium initially, then virus; or two doses of medium. immediately and 3, 5, 10, and 20 days after the second inoculation, the nasal passages, middle ears, larynges, trache ... | 1987 | 2823444 |
| transmission of sialodacryoadenitis virus in rats. | | 1987 | 2826876 |
| graft-versus-host disease and sialodacryoadenitis viral infection in bone marrow transplanted rats. | the effect of a localized viral infection on the occurrence of graft-vs.-host disease (gvhd) was examined in allogeneic rat bone marrow chimeras (aci/lew). animals without clinical evidence of gvhd, 62 days after bone marrow transplant, were infected in salivary and lacrimal glands with sialodacryoadenitis virus (sdav), and sacrificed 8-25 days postinfection. using established histologic criteria, gvhd was found more frequently in salivary and lacrimal glands of sdav-infected chimeras than uninf ... | 1988 | 2837842 |
| depletion of salivary gland epidermal growth factor by sialodacryoadenitis virus infection in the wistar rat. | male and female wistar rats 2 to 15 months of age were inoculated intranasally with sialoda-cryoadenitis (sda) virus and killed at 8 to 21 days post-inoculation (pi). submandibular glands were evaluated by light and electron microscopy, and levels of salivary gland epidermal growth factor (egf) were quantitated by cytochemistry and competitive radioreceptor assay. apical granules in the epithelial cells of the granular convoluted tubules (gct) were selectively depleted during the acute and conva ... | 1988 | 2839922 |
| inhibition of phagocytosis and interleukin-1 production in pulmonary macrophages from rats with sialodacryoadenitis virus infection. | to test whether or not sialodacryoadenitis virus (sdav) infection in rats affects pulmonary macrophage function, we intranasally inoculated pathogen-free f344 rats with sdav and collected alveolar and interstitial macrophages 5 d later. we assessed fc receptor-mediated attachment and phagocytosis by phase-contrast microscopic examination of monolayers of alveolar and interstitial macrophages incubated with zymosan, nonopsonized sheep erythrocytes, or erythrocytes opsonized with rabbit antisheep- ... | 1988 | 2841399 |
| reactivities of 4 murine coronavirus antigens with immunized or naturally infected rat sera by enzyme linked immunosorbent assay. | four murine coronavirus antigens, sialodacryoadenitis virus (sdav) strain tg, parker's rat coronavirus (pcv) strain 8190, mouse hepatitis virus (mhv) strains s and nuu, were examined for their reactivities to hyperimmunized and naturally infected rat sera by elisa. with the immunized sera, sdav and pcv antigens reacted best with respective homologous sera. mhv antigens reacted with all antisera, anti-sdav, anti-pcv, and anti-mhv-s at approximately the same level, and mhv-s showed a slightly high ... | 1988 | 2843391 |
| experimental sialodacryoadenitis virus infection in athymic cd-1 mice. | the purpose of the study was to investigate the susceptibility of nude mice to sialodacryoadenitis virus. young adult male cd-1 nude mice were inoculated intranasally with virus, killed at 2, 4, 6, 8, 10 and 20 days postinoculation and examined for virus-induced lesions in tissues including respiratory tract. inoculated and control mice were examined by virus isolation and serology. in a companion study, male wistar rats were inoculated intranasally with the same inoculum, and examined by histop ... | 1988 | 2844379 |
| the effect of selected viruses on corynebacterium kutscheri infection in rats. | the influence of selected viral pathogens on rats that were previously infected with corynebacterium kutscheri was investigated. a series of three separate experiments were performed to test the effect of sialodacryoadenitis virus, sendai virus and rat virus. in each experiment, weanling rats were divided into three groups (c. kutscheri-inoculated, virus-inoculated and c. kutscheri plus virus-inoculated). two groups were inoculated oronasally with c. kutscheri to establish subclinical infections ... | 1988 | 2848153 |
| epizootiological observations of natural and experimental infection with sialodacryoadenitis virus in rats. | the epizootiology of sialodacryoadenitis (sda) was studied in experimentally and naturally infected rats. the infectivity of sda virus (sdav) in intranasally infected rats was lost by seven days after infection as determined by contact transmission. after experimental infection, sn antibody appeared earlier and titers were detectable longer than cf antibody. the prevalence of sn antibody-positive rats in naturally infected colonies remained high, whereas an increase in the prevalence of cf antib ... | 1985 | 2987613 |
| central nervous system lesions in suckling mice and rats inoculated intranasally with sialodacryoadenitis virus. | suckling cd-1 and cfw mice and wi wistar rats were inoculated intranasally with sialodacryoadenitis virus. in animals inoculated during the first week of life, there was an acute necrotizing encephalitis with malacia and minimal inflammatory cell response. in mice and rats which survived for up to 12 days post inoculation, loss of brain substance, gitter cells and occasionally mineralized debris were seen. viral antigen was readily demonstrated in neurons and nasal epithelium in trypsin-treated, ... | 1986 | 3004003 |
| sialodacryoadenitis virus-associated lesions in the lower respiratory tract of rats. | eight- to 10-week-old outbred wistar rats were inoculated intranasally with 10(2.9) medium mouse lethal infective doses of sialodacryoadenitis (sda) virus. sham inoculated control rats and challenged rats were killed at 1 day intervals for the first 8 days, then on days 10, 12, 14, and 20. typical lesions associated with sda were seen microscopically in the salivary and lacrimal glands of inoculated rats. in addition, laryngitis, tracheitis, bronchitis, bronchiolitis, and multifocal alveolitis w ... | 1986 | 3014706 |
| prevalence of natural virus infections in laboratory mice and rats used in canada. | results of serological tests carried out over a period of 6 years to detect the presence of antibodies against 14 indigenous viruses in mice and rats used in 32 canadian institutions are reported. close to 20,000 individual sera were tested by the complement fixation or the hemagglutination inhibition technics. in order of mouse colony prevalence the six most common viruses present were pneumonia virus of mice, mouse hepatitis virus, rat virus, minute virus of mice, sendai, and theiler's mouse e ... | 1986 | 3084866 |
| cataractogenic effect of cyclosporin a: a new adverse effect observed in the rat. | in a study designed to test the long-term nephrotoxic effects of cyclosporin a (cya), 11 of 13 rats given cya, 25 mg/kg per day for 8 months, developed cataract. none of the 15 rats given cya 12.5 mg/kg per day, nor of the controls given vehicle only (n = 10), developed this lesion. in a subsequent study, 15 rats were given cya 25 mg/kg per day, 15 were given 12.5 mg/kg per day, and 10 controls were given the vehicle only. after 16 weeks, three rats of the group on cya 25 mg/kg per day had devel ... | 1987 | 3110684 |
| aspergillus rhinitis in wistar (crl:(wi)br) rats. | in two separate 24 month studies on the carcinogenic effect of single cadmium chloride injections in male wistar (crl:(wi)br) rats, a total of 22% (129/597) of animals studied histologically were found to have chronic suppurative rhinitis caused by aspergillus fumigatus. the diagnosis was based on characteristic conidial heads present in the sections, and positive methenamine-grocott (gms) staining of septate hyphae with dichotomous branching at angles of 45 degrees. fungal hyphae balls, surroun ... | 1988 | 3374092 |
| replication of sialodacryoadenitis virus of rat in lbc cell culture. brief report. | sialodacryoadenitis virus of rat readily propagated and induced marked cytopathic effect in a rat cell line, lbc cell culture, which provides a sensitive, practical assay system for viral infectivity and neutralizing antibody, and a satisfactory source of the virus. | 1986 | 3954597 |
| growth of rat sialodacryoadenitis viruses in lbc cell culture. | | 1986 | 3959379 |
| comparison of strain susceptibility to experimental sialodacryoadenitis in rats. | wistar, sprague-dawley, and long-evans outbred rats, and the fischer344 inbred strain were inoculated intranasally with 10(3) tcid50 of sialodacryoadenitis virus at approximately 9 weeks of age. paired animals were killed at 2-day intervals post inoculation up to 2 weeks, then at 20 days. a comparison of strain susceptibility to sialodacryoadenitis virus was made using the following criteria: histopathology, immunofluorescent microscopy, serology and serum amylase activity. all four strains were ... | 1984 | 6205217 |
| diagnosis of sialodacryoadenitis virus infection of rats in a virulent enzootic outbreak. | in a natural outbreak of sialodacryoadenitis virus it was observed that the incidence of clinical signs in spontaneous-hypertensive rats was 100%, and that these signs were of a severity not observed before in other strains of rats. rats free of the virus were introduced so that the progress of the disease could be studied under natural conditions of spontaneous spread from the enzootically-affected breeding colony. the pathogenesis of the infection in these sprague-dawley rats has been recorded ... | 1981 | 6281552 |
| characterization of a coronavirus isolated from rats with sialoadenitis. | a causative agent, provisionally designated as cars, was isolated from the enlarged submaxillary gland of rat which was characterized as a sialoadenitis, using mouse-derived balb/c3t3 clone a31 (3t3) cell culture. the virus could be propagated in 3t3 cell culture where it produced multinucleated giant cells and formed clear plaques. it was identified as a member of the coronavirus group from the following results: rna content was suggested by the lack of the effect of cytosine arabinoside, the i ... | 1982 | 6289776 |
| an immunofluorescence test for detection of serum antibody to rodent coronaviruses. | an indirect immunofluorescence test, using cultured cells infected with two strains of mouse hepatitis virus, was developed for detection of antibody to rodent coronaviruses. the immunofluorescence test detected serum antibody to mouse hepatitis virus and rat sialodacryoadenitis virus earlier than the neutralization test. in the case of mouse hepatitis virus, the results of the immunofluorescence test closely paralleled those obtained with a commercially available enzyme-linked immunosorbent ass ... | 1983 | 6304421 |
| pathogenicity of sialodacryoadenitis virus for rats after brain passages in suckling mice. | | 1982 | 7131854 |
| isolation and properties of sialodacryoadenitis virus of rats. | pathogenic agents were isolated from affected salivary glands of rats with sialodacryoadenitis (sda) by means of intercerebral inoculation to newborn mice and inoculation to primary rat kidney cell cultures. the properties of these isolates, irrespective of the isolation techniques, were in general agreement with that of sda virus strain 681, and they were identified as sda virus. in addition to the known properties, following characteristics were noticed: (1) particles of sda virus bore two dif ... | 1980 | 7202529 |
| development and optimization of plaque assays for rat coronaviruses. | plaque assays under sephadex or agarose overlays are described for rat coronaviruses (rcvs) grown in l2 mouse fibroblasts. a plaque assay using sephadex was simple; however, viable plaques could not be collected for propagation, and fixation was necessary before evaluation. plaque formation under agarose was optimized using diethylaminoethyl-dextran (deae-d) in the pre-treatment and absorption media and trypsin added to the absorption media and agarose overlay. the use of deae-d alone, trypsin a ... | 1993 | 7689580 |
| effect of time of exposure to rat coronavirus and mycoplasma pulmonis on respiratory tract lesions in the wistar rat. | the effects of time of exposure on the progression of pulmonary lesions in rats inoculated with mycoplasma pulmonis and the rat coronavirus, sialodacryoadenitis virus (sdav) were studied, using six groups of 18 spf wistar rats (n = 108). rats were inoculated intranasally as follows: group 1, sterile medium only; group 2, sterile medium followed one week later by 150 tcid50 sdav; group 3, sterile medium followed by 10(5.7) colony forming units of m. pulmonis; group 4, sdav followed one week later ... | 1995 | 7704844 |
| morphologic changes in the nasal cavity associated with sialodacryoadenitis virus infection in the wistar rat. | a sequential study of lesions of the nasal cavity associated with sialodacryoadenitis virus (sdav) infection was made in the laboratory rat. wistar rats were intranasally inoculated with approximately 10(3) tcid50 of the coronavirus sdav. transverse sections of four regions of the nasal cavity from inoculated and control animals were examined by light microscopy and immunohistochemistry at 2, 4, 6, 8, 10, and 14 days postinoculation (pi). lesions were observed in the following regions of the upp ... | 1995 | 7725592 |
| preliminary characterization of the structural proteins of the coronaviruses, sialodacryoadenitis virus and parker's rat coronavirus. | a procedure was developed for the partial purification of the rat coronaviruses, sialodacryoadenitis virus (sdav) and parker's rat coronavirus (prc). the sdav and prc were replicated in l-2 cell monolayer cultures, precipitated with ammonium sulphate, and further concentrated using sucrose density gradient centrifugation. the major sdav and prc proteins were identified by immunoblotting and compared with those of the jhm strain of mouse hepatitis virus (mhv-jhm). monoclonal antibodies (mab) agai ... | 1994 | 8004548 |
| sialodacryoadenitis virus infection of rat lacrimal gland acinar cells. | | 1994 | 8030476 |
| elimination of sialodacryoadenitis virus from a rat production colony by using seropositive breeding animals. | | 1993 | 8158996 |
| effects of viral and mycoplasmal infections, ammonia exposure, vitamin a deficiency, host age, and organism strain on adherence of mycoplasma pulmonis in cultured rat tracheas. | adherence to host cells is thought to be a pathogenetic mechanism in mycoplasmal diseases, thus, factors affecting adherence could affect disease expression. to determine whether factors that affect expression of mycoplasma pulmonis respiratory disease in rats alter adherence of the organism to respiratory epithelium, we studied adherence of radiolabelled m. pulmonis in perfused whole rat tracheas. adherence was significantly increased in tracheas from rats with sialodacryoadenitis virus infecti ... | 1993 | 8277719 |
| [mating activity of male shr rats infected with sialodacryoadenitis virus]. | the male shr rats infected with sialodacryoadenitis (sda) virus did not show any abnormal mating activity. however, high mortality was seen in embryos of diseased dams after cage-mating with infected males on day 4 to day 11 postinoculation. | 1993 | 8390940 |
| sequence analysis of the nucleocapsid protein gene of rat coronavirus sdav-681. | the nucleotide sequence of the 3'-end of the genomic rna of sialodacryoadenitis virus strain 681 (sdav-681) was determined. a large open reading frame encoding a 454-amino-acid protein was identified as the nucleocapsid protein (n) gene, since the predicted protein is similar in size, chemical properties, and amino acid sequence to the n proteins of other coronaviruses. the amino acid variance of the n proteins between sdav and mouse hepatitis virus (mhv) is not markedly different from that amon ... | 1993 | 8438589 |
| isolation and characterization of sialodacryoadenitis virus (coronavirus) from rats by established cell line lbc. | the outbreak of sialoadenitis occurred in a laboratory rat colony and the causative agent was isolated from the affected salivary glands of diseased rats using the established cell line lbc. the isolate readily multiplied, producing clear cytopathic effects with syncytium formation, and it was identified virologically and serologically as rat sialodacryoadenitis virus. in attempts to isolate the virus by primary rat kidney (prk) cells and suckling mice as well as lbc cells, the lbc cells showed ... | 1995 | 8553708 |
| comparative severity of respiratory lesions of sialodacryoadenitis virus and sendai virus infections in lew and f344 rats. | in several chronic diseases, lesions are more severe in lew rats than in f344 rats. to determine whether or not acute viral diseases also are more severe in lew rats than in f344 rats, we inoculated 6-7-week-old lew and f344 rats with 10(7.2) cell culture infective units of sialodacryoadenitis virus or 10(4.7) infective units of sendai virus. twenty-four rats of each strain were given each virus. lesions in nasal passages, tracheas, intrapulmonary airways, and pulmonary alveoli in 6 or 12 rats i ... | 1995 | 8592801 |
| growth characteristics and protein profiles of prototype and wild-type rat coronavirus isolates grown in a cloned subline of mouse fibroblasts (l2p.176 cells). | rat coronaviruses (rcvs) infect laboratory rats and confound biomedical research results. in vitro systems developed so far have limited the growth in knowledge about rcvs by not permitting generation of plaque-cloned virus stocks, reliable isolation of rcvs from rat tissues, or growth of high titered stocks of all isolates. due to the fact that less than 20% of l2(percy) cells were becoming infected, sublines were produced and selected for maximal growth of rcvs. screening of 238 cell sublines ... | 1996 | 8725102 |
| replication of rat coronaviruses in intestinal cell line, rcn-9, derived from f344 rats. | to examine the susceptibility of the epithelial cell line to rat coronavirus (rcv), we inoculated sialodacryoadenitis virus and parker's rcv into five cell lines; jtc-19, rat l2, llc, rcn-9 and lbc cells originating in the lungs, intestines and mammary tumors of rodents. both rcvs were replicated in lbc and rcn-9 cells, but not in the others. the infectivity titers of both rcvs grown in rcn-9 cells were significantly higher than those in lbc cells in every passage (2.5-3.9 log rate). both rcvs r ... | 1996 | 8902504 |
| is hepatitis c virus a sialodacryoadenitis virus? | | 1997 | 9252169 |
| effect of sialodacryoadenitis virus exposure on acinar epithelial cells from the rat lacrimal gland. | sialodacryoadenitis virus (sdav), a rna coronavirus, induces degenerative, necrotic and atrophic alterations in acinar epithelial cells of the rat lacrimal gland. to begin to explore the underlying mechanism(s) of this viral effect, we sought in the present study to: (1) determine whether sdav invades and replicates in lacrimal gland acinar cells in vitro and (2) assess whether short-term sdav challenge interferes with the viability or function of acinar cells in vitro. for comparison we also ev ... | 1997 | 9326763 |
| primary structure of the sialodacryoadenitis virus genome: sequence of the structural-protein region and its application for differential diagnosis. | sialodacryoadenitis virus (sdav) is a coronavirus that is commonly found in laboratory rats and that causes sialodacryoadenitis and respiratory illness. we cloned and sequenced the 3' terminal 9.8 kb of the genomic rna and analyzed the structure of the viral genome. as with mouse hepatitis coronaviruses (mhvs), the sdav genome was able to code for a spike protein, a small membrane protein, a membrane-associated protein, and a nucleocapsid protein. in addition, the hemagglutinin-esterase gene cap ... | 2000 | 10882653 |
| nucleic acid deletions and copy number in rats. | rats fed either a cereal-based or purified diet of variable folate content (deficient, replete, or supplemented) inadvertently were infected with sialodacryoadenitis virus, which resulted in an increased frequency of hepatic mitochondrial dna (mtdna) deletions that persisted for three weeks after the period of acute signs of disease. the amount of the "common deletion" (4.8 kb, bases 8103-12937) in liver was measured by quantitative co-amplification of the mitochondrial d-loop and the mitochondr ... | 2002 | 12211281 |
| toxicology and carcinogenesis studies of bromoethane (ethyl bromide) (cas no. 74-96-4) in f344/n rats and b6c3f1 mice (inhalation studies). | bromoethane is an alkylating agent used primarily as a chemical intermediate in various organic syntheses. in toxicology and carcinogenesis studies, groups of f344/n rats and b6c3f1 mice of each sex received whole-body exposure to bromoethane (greater than 98% pure) once for 4 hours or for 6 hours per day, 5 days per week, for 14 days, 14 weeks, or 2 years. genetic toxicology studies were conducted in salmonella typhimurium and chinese hamster ovary (cho) cells. single-exposure, fourteen-day, an ... | 1989 | 12695778 |
| ntp toxicology and carcinogenesis studies of benzyl alcohol (cas no. 100-51-6) in f344/n rats and b6c3f1 mice (gavage studies). | toxicology and carcinogenesis studies of technical-grade benzyl alcohol (99% pure), a textile dye additive, solvent, and food flavoring agent, were conducted by administering the chemical by gavage in corn oil vehicle to groups of f344/n rats and b6c3f1 mice of each sex for 16 days, 13 weeks, or 2 years. short-term studies: in 16-day studies, all five male and five female rats and mice dosed with 2,000 mg/kg benzyl alcohol died. two of five male and 3/5 female rats and 1/5 male and 2/5 female mi ... | 1989 | 12724782 |
| common rna replication signals exist among group 2 coronaviruses: evidence for in vivo recombination between animal and human coronavirus molecules. | 5' and 3' utr sequences on the coronavirus genome are known to carry cis-acting elements for di rna replication and presumably also virus genome replication. 5' utr-adjacent coding sequences are also thought to harbor cis-acting elements. here we have determined the 5' utr and adjacent 289-nt sequences, and 3' utr sequences, for six group 2 coronaviruses and have compared them to each other and to three previously reported group 2 members. extensive regions of highly similar utr sequences were f ... | 2003 | 14592769 |
| recombinant viral sialate-o-acetylesterases. | viral o-acetylesterases were first identified in several viruses, including influenza c viruses and coronaviruses. these enzymes are capable of removing cellular receptors from the surface of target cells. hence they are also known as "receptor destroying" enzymes. we have cloned and expressed several recombinant viral o-acetylesterases. these enzymes were secreted from sf9 insect cells as chimeric proteins fused to egfp. a purification scheme to isolate the recombinant o-acetylesterase of influ ... | 2004 | 15454694 |
| ophthalmic lesions in dexamethasone-treated rats naturally infected with sialodacryoadenitis virus while concurrently used for pneumocystis carinii propagation. | | 1996 | 16457526 |
| rat coronaviruses infect rat alveolar type i epithelial cells and induce expression of cxc chemokines. | we analyzed the ability of two rat coronavirus (rcov) strains, sialodacryoadenitis virus (sdav) and parker's rcov (rcov-p), to infect rat alveolar type i cells and induce chemokine expression. primary rat alveolar type ii cells were transdifferentiated into the type i cell phenotype. type i cells were productively infected with sdav and rcov-p, and both live virus and uv-inactivated virus induced mrna and protein expression of three cxc chemokines: cinc-2, cinc-3, and lix, which are neutrophil c ... | 2007 | 17804032 |
| a survey of rodent-borne pathogens carried by wild-caught norway rats: a potential threat to laboratory rodent colonies. | unintentional infection of laboratory rodents can compromise scientific research as well as the health of the animals and animal handlers. the source of contamination often is unknown, but may be introduced by wild rats from surrounding environments. to determine whether rats in baltimore, maryland, usa carry infectious agents commonly found in laboratory rodent colonies, we live-trapped 162 rats during 2005 to 2006 and screened them for a panel of viruses, bacteria and parasites. antibodies aga ... | 2008 | 18348770 |
| microbial contaminations of laboratory mice and rats in taiwan from 2004 to 2007. | limited data are available on the pathogen status of contemporary rodent colonies in taiwan. here we summarized the rodent pathogen diagnostic records of the taiwan national laboratory animal center during a 4-y period that representing approximately 10% of the rodent colonies in taiwan. demand for pathogen diagnostic service increased continuously from 2004 to 2007, with a 20% increase each year. in 2007, more than 20% of the mouse colonies were positive for mouse parvovirus, mouse hepatitis vi ... | 2009 | 19653946 |
| rat respiratory coronavirus infection: replication in airway and alveolar epithelial cells and the innate immune response. | the rat coronavirus sialodacryoadenitis virus (sdav) causes respiratory infection and provides a system for investigating respiratory coronaviruses in a natural host. a viral suspension in the form of a microspray aerosol was delivered by intratracheal instillation into the distal lung of 6-8-week-old fischer 344 rats. sdav inoculation produced a 7 % body weight loss over a 5 day period that was followed by recovery over the next 7 days. sdav caused focal lesions in the lung, which were most sev ... | 2009 | 19741068 |
| simultaneous detection of antibodies to mouse hepatitis virus recombinant structural proteins by a microsphere-based multiplex fluorescence immunoassay. | we describe a new microsphere-based multiplex fluorescent immunoassay (mfi) using recombinant mouse hepatitis virus (mhv) proteins to detect antibodies to coronaviruses in mouse and rat sera. all the recombinant proteins, including nucleocapsid (n) and 3 subunits of spike protein, s1, s2, and smid, showed positive reactivity in mfi with mouse antisera to 4 mhv strains (mhv-s, -a59, -jhm, and -nu67) and rat antiserum to a strain of sialodacryoadenitis virus (sdav-681). the mfi was evaluated for i ... | 2011 | 21430123 |
| synthesis and inhibitory activity of sialic acid derivatives targeted at viral sialate-o-acetylesterases. | a series of sialosides modified at the 4- and 9-hydroxy group were synthesised and tested for inhibition of the viral haemagglutinin-esterase activity from various orthomyxoviruses and coronaviruses. while no inhibition of the sialate-4-o-acetylesterases from mouse hepatitis virus strain s or sialodacryoadenitis virus was found, a 9-o-methyl derivative displayed inhibitory activity against recombinant sialate-9-o-acetylesterase from influenza c virus. | 2011 | 21524502 |
| Effect of sialodacryoadenitis virus infection on axonal regeneration. | The effect of sialodacryoadenitis virus (SDAV) infection on axonal regeneration and functional recovery was investigated in male Lewis rats. Animals underwent unilateral tibial nerve transection, immediate repair, and treatment with either FK506 (treated) or control vehicle (untreated). Serial walking track analyses were performed to assess functional recovery. Nerves were harvested for morphometric analysis on postoperative day 18 after an SDAV outbreak occurred that affected the 12 experimenta ... | 2011 | 21866574 |
| efficacy of soiled bedding transfer for transmission of mouse and rat infections to sentinels: a systematic review. | this systematic review was conducted to gain insight into the efficacy of transmission of infectious agents to colony sentinels by soiled bedding transfer based on publications studying this subject in mice and rats. this information is essential to establish recommendations for the design of health monitoring programs which use sentinels to determine the microbiological status of laboratory animal colonies. | 2016 | 27518654 |
| sero-prevalence of rodent pathogens in india. | health monitoring is an integral part of laboratory animal quality standards. however, current or past prevalence data as well as regulatory requirements dictate the frequency, type and the expanse of health monitoring. in an effort to understand the prevalence of rodent pathogens in india, a preliminary study was carried out by sero-epidemiology. sera samples obtained from 26 public and private animal facilities were analyzed for the presence of antibodies against minute virus of mice (mvm), ec ... | 2015 | 26158453 |
| pathology of sialodacryoadenitis virus infection in newborn mice. | | 1983 | 6314018 |