PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Respirovirus”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1976

Experimental parainfluenza type 1 virus-induced encephalopathy in adult mice. Pathogenesis of chronic degenerative changes in the CNS.

The pathogenicity of the 6/94 strain of parainfluenza type 1 virus, originally isolated from multiple sclerosis brain, was studied in adult mouse brains. Intracerebral inoculation of the virus caused mononuclear cell infiltration in the form of perivascular cuffing and a diffuse exudation into the parenchymal tissue, preferentially in cerebral white matter, that resulted in marked degeneration over a 90-day observation period. Immunofluorescent staining revealed viral antigen in the ependymal lining cells only during the first seven days after infection. No correlation was found between the severity of the brain lesions and the level of circulating antiviral antibody, preexisting or newly produced.

Animals↗
PubMed1978

Respiratory syncytial virus infection. Rapid diagnosis in children by use of indirect immunofluorescence.

Specimens of 387 nasopharyngeal suction smears obtained from 354 children hospitalized with acute respiratory infections during an eight-month period were examined for the presence of respiratory syncytial (RS) virus by the indirect immunofluorescence antibody technique (IFAT) and by conventional tissue culture infectivity techniques. Respiratory syncytial virus was identified in nasopharyngeal suction smear specimens from 123 of these specimens (32%) with the use of both techniques. Of the specimens positive on tissue culture 92% were also positive for RS virus by IFAT. However, eight specimens positive for RS virus by tissue culture were negative by IFAT, although three of the specimens were technically unsuitable. Six percent of the specimens negative for RS virus by tissue culture were positive for RS virus antigen when tested by IFAT. Using IFAT, identification of RS virus could be accomplished within four to six hours, whereas isolation by tissue culture took an average period of ten days. These data suggest that IFAT is a reliable means for the rapid diagnosis of RS virus infection in infants and children.

Adolescent↗
PubMed1979

Clinical and physiological manifestations of bronchiolitis and pneumonia. Outcome of respiratory syncytial virus.

The physiological abnormalities and clinical correlates of 32 infants consecutively hospitalized with lower respiratory tract disease from respiratory syncytial virus (RSV) were studied in an attempt to characterized the infant most at risk for the acute and long-term complications of RSV infection. Arterial oxygen saturation (Sao2) determinations were obtained daily by means of an ear oximeter. On admission all infants were hypoxemic with a mean Sao2 of 87% (range, 74% to 95%). The mean of the lowest Soa2 recorded during their hospitalization was 85.5% (range, 53% to 96%). The hypoxemia improved little during hospitalization but showed improvement three to seven weeks later. The severity of the hypoxemia correlated significantly with the duration of viral shedding, occurrence of apnea, respiratory rate, age, and percentage of immature neutrophils. Clinical severity did not correlate with the degree of hypoxemia.

Age Factors↗
PubMedDate not supplied

Antibody levels to parainfluenza, rubella, measles, and influenza A virus in children with polymyositis.

The CF and HI antibody titers to rubella and measles viruses, the CF titers to influenxa A, and the HI titers to parainfluenza 1, 2, and 3 were carried out on the sera of 20 patients with childhood polymyositis and their matched controls. The titers for measles, parainfluenxa 1, and influenza A were slightly higher for patients than for controls. The control group had antibody titers to rubella and parainfluenza 2 and 3 higher than or similar to those of patients. Strong patterns or significant differences for a given virus or virus group were not encountered.

Adolescent↗
PubMed1978

Hyporesponsiveness of lymphocytes to virus antigens in rheumatoid arthritis.

The immune response of peripheral blood lymphocytes to measles, rubella, parainfluenza types 1, 2, and 3 RNA virus antigens and to varicella-zoster and herpes virus type 1 DNA virus antigens was evaluated in 14 patients with rheumatoid arthritis (RA) and 14 matched controls by assessing 3H-thymidine incorporation. The results demonstrated hyporesponsivenss of lymphocytes from RA patients to virus antigens and phytohemagglutinin (PHA), which did not appear to be nonspecific because of a lack of correlation between response to virus antigens and response to mitogens. The patterns of decreased responsiveness was suggestive of a relative restriction of hyporesponsiveness to RNA virus antigens.

Antigens, Viral↗
PubMedDate not supplied

Reactivities of systemic lupus erythematosus sera with cellular and virus antigen preparations.

Sera of patients with systemic lupus erythematosus (SLE) showed significantly higher complement fixation reactivities with 8 of 10 virus antigen preparations compared to sera of normal subjects, including virus workers, confirming earlier observations. However, one-third of SLE sera were also reactive with cellular antigens, prepared in a manner identical to viral antigens, but from cells not infected with virus. By contrast, only one of 49 normal sera showed reactivity with one of nine cellular antigens, at a minimal titer. Apparently heightened reactivities of SLE sera with virus antigens could be explained in many instances on the basis of reactions with cellular antigens. Serum reactivities with nonviral tissue antigens in SLE must be considered in interpretation of immunologic studies related to viruses and SLE.

Antigens↗
PubMed1978

Evaluation of five temperature-sensitive mutants of respiratory syncytial virus in primates: II. Genetic analysis of virus recovered during infection.

Five temperature-sensitive (ts) mutants of respiratory syncytial (RS) virus (ts-1, ts-1 NG-1, ts-1 NG-16, ts-2, and ts-7), previously evaluated forinfectivity and virulence in chimpanzees and owl monkeys, were also assayed for in vivo genetic stability. None of the five mutants tested was completely stable genetically. Thus, virus which had lost some or all of the ts property was recovered from each infected chimpanzee. Significantly, each ts-1 NG-1 isolate retained some degree of temperature sensitivity and hence was not true wild-type virus. Clonal analysis of viruses shed by ts-1, ts-1 NG-1, ts-1 NG-16, or ts-7 infected chimpanzees indicated that in most instances only a minority of the virus shed was altered genetically. Of five chimpanzees infected with the ts-2 mutant, three shed only ts virus, and the remaining two chimpanzees shed only ts+ virus. Such ts+ virus proved to be avirulent when evaluated in chimpanzees or owl monkeys, indicating that loss of the ts property did not restore virulence. Based upon these findings, the ts-2 mutant appears to be a suitable candidate for clinical trials in man.

Animals↗
PubMed2025

Clinical and Epidemiological Insights into a Parainfluenza Virus Type 3 Outbreak in Multiple Myeloma Patients.

Human parainfluenza virus type 3 (HPIV-3) can be responsible for mild to severe respiratory infections and hospital epidemics. We investigated an outbreak in a hematology unit. Respiratory viruses were screened using multiplex PCR. HPIV-3 quantification and whole-genome sequencing were performed on HPIV-3 positive respiratory samples. Clinical characteristics, infection progression, incidence rates of respiratory viruses within the hospital and detection of respiratory viruses were documented, along with the reinforcement of infection prevention and control (IPC) measures implemented. Between November 2022, and January 2023, HPIV-3 was identified in 20 of 113 hematology patients (17.7%), of whom 80% had multiple myeloma. A majority of HPIV-3-positive patients developed pneumonia (60%), and mortality was notably higher (35%) compared to patients who were negative (3%, p&#x2009;<&#x2009;0.0001). Respiratory HPIV-3 viral loads were similar between patients with and without pneumonia. In parallel, HPIV-3 incidence in the hospital overall was lower than in the hematology unit (p&#x2009;<&#x2009;0.0001). Air virus screening showed the detection of HPIV-3 in the air in different areas, and whole-genome sequencing confirmed the circulation of a single HPIV-3 strain. Strengthened IPC measures were associated with the containment of the outbreak. HPIV-3 has high epidemic potential in patients with multiple myeloma and causes severe infections. Our findings highlight the need for routine HPIV-3 testing in hematology units.

Humans↗
PubMed1977

Serological response of multiple sclerosis patients and controls to 6/94-parainfluenza virus.

The serological responses of 195 multiple sclerosis (MS) patients and 251 controls were tested against 6/94-parainfluenza virus, which was previously isolated from brain tissue of two patients with MS. The hemagglutination-inhibition titers of greater than or equal to 1: 128 were found more frequently in MS patients (21.5%) than in controls (14.0%). However, the geometric mean titers did not differ between these two groups. The present study concludes that a causal relationship of 6/94-virus to MS, based on a specific immune response, is improbable, although it does not exclude the possibility of a pathogenetic significance of the agent in the cases from which the autopsy material was derived.

Adult↗
PubMed1977

Cell receptors for paramyxoviruses.

Treatment of chick embryo fibroblasts, calf kidney and BHK cells for 30 minutes with the enzyme neuraminidase from Vibrio cholerae causes an enhancement of the per cent of attached NDV virions. This enhancement does not depend on the multiplicity of infection. The quantity of spontaneously eluted and cellbound virus is two times greater than the quantity of the same virus derived from control cells. N-acetyl-neuramin lactose inhibits the effect of Vibrio cholerae neuraminidase. After prolonged action of this enzyme, the quantity of adsorbed NDV diminishes. Treatment of the same cells with neuraminidase from influenza virus decreases the per cent of adsorbed NDV with respect to controls. The other paramyxovirus--bovine parainfluenza 3 virus adsorbs also more intensively on cells treated with Vibrio cholerae neuraminidase. It is suggested that partial hydrolysis of NANA molecules causes a rearrangement of the cell surface charged groups and thus allows a more effective contact between paramyxoviruses and the cell.

Adsorption↗
PubMed1977

Components of parainfluenza-3 virus, SLP-strain, reacting in assays of cell-mediated immunity in cattle.

Parainfluenza-3 virus was isolated by affinity chromatography, including a purification step with immobilized lectin Vicia erwilia. The peplomers of disintegrated virus were similarily isolated using another carbohydrate-specific lectin Vicia crotalaria. The whole virion and the peplomers were both active as antigens in the leucocyte migration inhibition, lymphocyte stimulation and skin hypersensitivity tests. The remaining virus material, freed of detergents used for virus disintegration and containing nucleocapsids, did not act as antigen in these tests of cell-mediated immunity.

Adsorption↗
PubMed1979

Fluorescence polarization of DPH-labeled cells adsorbing viruses and its diagnostic potential.

Mammalian or avian cells were labeled with a fluorescent probe DPH (1,6-diphenyl-1,3,5-hexatriene). Within a few minutes after adsorption of various naked and enveloped viruses, the degree of fluorescence polarization (P) of the DPH embedded in the adsorbing cells as measured at 37 degrees C, was reduced, a finding indicating a decrease in the microviscosity of the lipids in the cell membrane. This change of fluidity was proportional to the concentration of the adsorbing virus and could be abolished or inhibited by homologous specific antiviral sera, but not by heterologous sera. Potential use of fluorescence polarization tests is described for titration of virus concentration, as well as for serological identification of a virus.

Adsorption↗
PubMed1979

Non-productive paramyxovirus infection: Nariva virus infection in hamsters.

The pathogenesis of infection with Nariva virus (NV)--recently classified as a paramyxovirus--was studied in the hamster, an animal closely related to the natural host. Intracranial inoculation of suckling hamsters produces an acute necrotizing encephalitis with large amounts of infectious virus and virus antigen in the brain. In contrast, weanling hamsters have only small amounts of infectious virus and only early in the disease, when they are well; later, when clinically ill, they have a non-productive infection with continuing evidence of viral antigen, but no detectable infectious virus. Weanlings die later than sucklings with less cerebral parenchymal necrosis. The integrity of the immune system affects the expression of NV since brain tissue from anti-lymphocyte serum (ALS) treated infected weanling hamsters have more infectious virus, and for longer periods, than brain tissue from untreated infected weanling hamsters. Changing susceptibility of the host's neural cells may also be involved in determining the course of the illness and expression of the virus since: 1) ALS treatment does not influence the clinical course of the disease or pathology, 2) ALS treated weanlings still have much lower levels of infectious virus than sucklings, 3) infected weanling and suckling hamsters have a similar time course of development of NV neutralizing antibody.

Animals↗