Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014070 (encephalomyelitis)
 13,017 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Spinal cord sections from mice injected with Theiler's murine encephalomyelitis virus (TMEV) and surviving for 1 year and longer after infection were stained for virus antigen by two immunohistochemical techniques. Virus antigen was detected from 1 to 2 1/2 years after infection, a time when no virus was recovered at an assay sensitivity of 50 plaque-forming units per gram of tissue. The implication this has regarding the detection of a virus in MS is discussed.
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PMID:Theiler's virus antigen detected in mouse spinal cord 2 1/2 years after infection. 608 5

Enzyme immunoassays (EIAs) for eastern equine encephalomyelitis (EEE) and Highlands J (HJ) virus antigens were compared in a retrospective study with standard virus isolation procedures (VIP) for detection of alpha virus-infected mosquito pools. The original VIP was a plaque assay in chick embryo cell culture, and was performed in the years from 1979 to 1981. Using the original VIP as the reference standard, the sensitivity rate of the EIA was 0.7674 and the false negative rate was 0.2326. However, when the storage age and the initial virus titer of the sample were considered, the sensitivity rate increased. For samples containing greater than 1,500 plaque-forming units (PFU) per ml of virus during the original VIP, the sensitivity rate of the EIA was 0.97; but the rate declined to 0.14 for those originally containing less than 500 PFU per ml. Most of the false negatives (68%) occurred with samples containing less than 500 PFU per ml. Presumably the low quantities of virus in these 50 pools were lost during storage and handling; virus was obtained from only 16% (8/50) during reisolation attempts using BHK-21 cells. Specificity of the EIA was excellent; no false positive results were obtained and serological identification was identical to that determined by plaque reduction neutralization in greater than 98% of the pools examined. Characteristics of the pools, such as pool size, species of mosquitoes, or gravidity did not affect the EIA results. These studies support the use of EIAs in surveillance programs attempting to determine infection rates of known arboviruses in vector populations.
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PMID:Detection of eastern equine encephalomyelitis virus and Highlands J virus antigens within mosquito pools by enzyme immunoassay (EIA). II. Retrospective field test of the EIA. 614 99

A solid phase radioimmunoassay (RIA) for the detection of antibodies to myelin basic protein (MBP) in sera has been developed employing MBP-coated flexible polyvinylchloride microtiter trays and [125I]protein-A as the radiolabel. [125I]Protein-A directly binds to the Fc region of serum IgG from several animal species and serves as an excellent reagent for detecting antibody. It can also be used to bind to a second antibody ligand, thereby making it useful even when it does not bind directly to the primary antibody Fc region. The use of one preparation of [125I]protein-A label allows sera from several species to be tested for antibodies to MBP simultaneously, thereby making this RIA technically simple, rapid and economical. This assay has been particularly useful in examining serum samples from animals with experimental autoimmune encephalomyelitis and hypomyelinogenisis congenita. In patients with multiple sclerosis low levels of antibody to MBP can be detected in cerebrospinal fluid (CSF) and acid-eluted extracts from brain plaque material; detection of low levels of antibody in human serum has not been possible due to non-specific binding of human serum Ig in this RIA.
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PMID:Detection of antibodies to myelin basic protein by solid-phase radioimmunoassay with [125I]protein A. 617 94

The genetic changes occurring in the BeAn strain of Theiler's murine encephalomyelitis virus (TMEV) during persistent infection in the mouse central nervous system (CNS) were studied. RNase T1-oligonucleotide fingerprinting of the RNAs of 28 BeAn viruses isolated at various times postinfection (p.i.) demonstrated that mutation occurred throughout the infection. Although plaque-purified BeAn virus was used to inoculate mice intracerebrally, genetically different viruses were recovered from the CNS. One to three oligonucleotide changes were found up to Day 152 p.i., but all three viruses isolated at Day 180 had four to nine oligonucleotide changes. No pattern of oligonucleotide changes occurring in different virus isolates was found, yet three viruses isolated from different animals at Day 180 had the same four new oligonucleotides. Overall, the number of oligonucleotide changes represented a 0.1 to 1.2% change in the virus genome. In addition, the analytical two-dimensional gel technique of P.Z. O'Farrell, H.M. Goodman, and P.H. O'Farrell (Cell 12, 1133-1142, 1977) suggested that mutation occurred in all virus isolates. In nine isolates, one to three proteins were found to have charge changes, and in general, as many nonstructural proteins had charge changes as structural proteins. P20, a nonstructural protein probably equivalent to the protease described for encephalomyocarditis virus, was found to have shifted cathodally in six different viruses. Several virus isolates had doublet patterns, suggesting the possibility that within the CNS, subpopulations existed which had proteins of slightly different charge or that virus-specified proteins had been modified after translation. Finally, antigenic variation of neutralizing site(s) on BeAn virus isolates as a way for virus to evade immune surveillance and thereby maintain the persistent state was studied. The ability of mouse serum to neutralize persisting virus isolates was not significantly different from the ability to neutralize the infecting virus. Therefore, antigenic variation does not appear to be a factor in TMEV persistence.
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PMID:Analysis of genetic variation in Theiler's virus during persistent infection in the mouse central nervous system. 619 87

Theiler's murine encephalomyelitis virus (TMEV) is an enteric pathogen of mice which causes acute and chronic neurological disorders in the natural host. When brain-derived stocks of TMEV isolates are adapted to cell culture they predominantly form either large or small plaques. In this study the type of central nervous system (CNS) infection (acute versus chronic) and the associated disease occurring in mice inoculated intracerebrally with large and small plaque strains of TMEV was investigated. Large and small plaque strains of TMEV were found to vary in virulence, type of neurological disease produced and ability to establish persistent CNS infection in mice. Two large plaque strains, GDVII and FA viruses, were highly virulent, produced acute encephalitis, but were cleared from the nervous systems of surviving animals. Therefore, it appears that these large plaque variants do not cause persistent CNS infection in mice. In contrast, five small plaque strains, DA, WW, TO4, Yale and BeAn8386 viruses, were relatively avirulent, usually produced no illness during the first month after inoculation, but readily established persistent CNS infection in mice. Persistently infected mice later developed demyelinating disease. Having identified strains of TMEV that differ regarding their ability to persist, we now hope to be able to exploit this difference in elucidating the basic mechanism(s) of TMEV persistence.
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PMID:Persistent Theiler's murine encephalomyelitis virus infection in mice depends on plaque size. 624 40

The model system of central nervous system (CNS) disease induced by mouse hepatitis virus type 4 (MHV-4) is explored by comparison of wild type (wt) MHV-4 and two temperature-sensitive (ts) mutants, designated ts8 and ts15, in BALB/c and SJL/J mice. In BALB/c mice, 3 plaque-forming units (PFU) of wt MHV-4 given intracerebrally caused fatal encephalomyelitis in all mice by 7 days after infection, with spread of virus outside the CNS, especially to liver. In SJL/J mice, 3 PFU of wt virus was cleared within 2-3 days, with little spread, and up tp 100 PFU failed to cause fatal encephalomyelitis. However, larger amounts of virus, like 1000 PFU, caused fatal encephalomyelitis in SJL/J mice. In contrast, 10(4) PFU of MHV-4 ts8 did not cause death in either BALB/c or SJL/J mice, and persisted in the CNS of both strains while retaining its ts phenotype. There was significatnly less spread of virus outside the CNS. BALB/c mice usually showed demyelination, remyelination, and recurrent demyelination with ts8, while SJL/J mice only rarely had lesions. Intracerebral inoculation with 10(4) PFU of MHV-4 ts15 was associated with a persistent infection in CNS and liver of BALB/c mice; however, only occasional demyelination and hepatic lesions occurred. TS15 did not cause death in either BALB/c or SJL/J mice and did not cause histopathologic injury in SJL/J mice.
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PMID:Selected mutants of mouse hepatitis virus type 4 (JHM strain) induce different CNS diseases. Pathobiology of disease induced by wild type and mutants ts8 and ts15 in BALB/c and SJL/J mice. 629 96

Two plaque-size variants of the neurotropic JHM strain of mouse hepatitis virus have been isolated from the virus stock after eight serial passages in suckling mouse brain. One variant, JHM-DL, produces large plaques, while the other, JHM-DS, produces small plaques in tissue culture. DS replicates more slowly, has a lower virus yield in vitro, and is less virulent for mice than DL. They also differ in their pathogenicity for mice: JHM-DL infection results in acute encephalomyelitis while JHM-DS infection results in demyelination. Oligonucleotide fingerprint analysis of the RNA genomes of these two variants revealed that they had almost identical genetic sequences. Each variant, however, had a unique oligonucleotide spot not found in the other. The unique spot of the large plaque variant, JHM-DL, was localized at approximately 3 to 5 kb from the 3' end, while the JHM-DS unique spot was mapped at 14 to 15 kb from the 3' end of the genome. We have further shown that these oligonucleotide changes are not correlated with the plaque morphology. These two viruses may be useful for studying the molecular basis of virus-induced demyelination.
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PMID:Murine coronaviruses: isolation and characterization of two plaque morphology variants of the JHM neurotropic strain. 629 77

The possibility of producing ts mutants of Sindbis and eastern equine encephalomyelitis (EEE) virus by treatment of replicating virus with N-methyl-N-nitro-N-nitrosoguanidine was studied. N-methyl-N-nitro-N-nitrosoguanidine added in a concentration of 20 micrograms/ml to chick fibroblast cultures infected with Sindbis virus for 4 hours was shown to induce ts mutations in the virus. Under similar conditions no ts mutants of EEE virus could be obtained. The content of ts mutants in the mutagenized populations of Sindbis virus was 7.9%. Eight ts mutants were isolated. Their temperature-sensitive defect was expressed to various degrees. The plaque-forming efficiency at 40 degrees C/35 degrees C ranged from 6.3 X 10(-2) to 1.7 X 10(-8), and the yield from 5.6 X 10(-2) to 2.8 X 10(-4).
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PMID:[Induction of alphavirus ts-mutations by N-methyl-N-nitro-N-nitrosoguanidine added to the replicating virus]. 632 93

Young male white Swiss mice were fed control diet or diet supplemented with 20 or 10 parts per million (ppm) of T-2 toxin for two or three weeks. These mice then were inoculated with herpes simplex virus type 1 (HSV-1) (9.6 x 10(6) plaque forming units) intraperitoneally. To compare the effects of T-2 toxin against a known immunosuppressive drug, cyclophosphamide was injected intraperitoneally at 150 mg/kg, 24 hours after treatment with HSV-1, into mice fed the control diet. Mice were necropsied and tissues were collected for microscopic and virologic examination. White Swiss mice which consumed a daily diet containing 20 ppm of T-2 toxin for two or three weeks were highly susceptible to HSV-1 infection and 27 of 36 (75%) died as a result of extensive hepatic and adrenal necrosis. Although HSV-1 was isolated from livers and brains of mice fed 20 ppm of T-2 toxin for two or three weeks, there was little or no inflammatory response found in the adrenals, livers, spinal cords, brains, or ganglia. The necrotizing encephalomyelitis observed in control mice was absent. High levels of dietary T-2 toxin appeared to be more immunosuppressive than cyclophosphamide because only one mouse died after treatment with HSV-1 and cyclophosphamide. Mice treated with cyclophosphamide had changes in brain, spinal cord, spleens, thymus, and bone marrow which were similar to those fed 20 ppm of T-2 toxin and infected with HSV-1, however, liver lesions were much less severe. HSV-1-infected mice on a diet with 10 ppm T-2 toxin had lesions of intermediate severity when compared with HSV-1-infected mice fed a diet with 20 ppm T-2 toxin and HSV-1-infected mice on control diets. Necrosis was less extensive in the livers and adrenals. The infrequent isolation of virus from liver and brain was consistent with the lack of intranuclear inclusion bodies and a more marked inflammatory response. Ten ppm of dietary T-2 toxin only depressed bone marrow and splenic red pulp to a mild or moderate degree. This may have enhanced the necrotizing encephalomyelitis observed in mice killed on days 6 and 8 after HSV-1 infection. Liver lesions were mild and those of the adrenals were moderate in mice fed control diet. The rare isolation of HSV-1 from the liver and brain and the findings of a moderate to severe necrotizing encephalomyelitis in these mice was consistent with an essentially functional immune system.
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PMID:The effects of dietary T-2 toxin on acute herpes simplex virus type 1 infection in mice. 664 41

ESK cells were shown to be a good medium for propagating the 67N strain of porcine haemagglutinating encephalomyelitis virus, although no cytopathic effect was observed. The virus induced a readily recognizable cytopathic effect in ESK cells, when a noncytotoxic amount of diethylaminoethyl-dextran (DEAE-dextran) was incorporated in the culture medium. Based on this finding, a sensitive, practical assay method for the virus was developed. When DEAE-dextran was incorporated in the agar overlay medium, 67N virus formed plaques in ESK cell monolayers. The cytopathic effect as well as the plaque formation were specifically inhibited by antisera against the virus. Neutralization tests were developed on the basis of these findings. Neutralization and haemagglutination-inhibition tests on swine serum samples indicated a wide dissemination of haemagglutinating encephalomyelitis virus or antigenically-related viruses in Japanese pigs.
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PMID:Inducement of cytopathic changes and plaque formation by porcine haemagglutinating encephalomyelitis virus. 665 11


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