Biomedical subjects

P Payment

Publications and source records attributed to P Payment.

87 records · Page 5Linked to original sources

PubMed1978

[Evaluation of the efficiency of the adsorption-elution technic for poliovirus 1 on fiber glass filters: application in the virological analysis of 100 ml to 1000 1 of water].

The efficiency of the adsorption-elution technique using fiber glass filters to concentrate viruses from water was evaluated to detect poliovirus type 1 in drinking, river, and sewage water. At pH 3.5 and with 5 X 10(-4) M aluminium chloride more than 99% were adsorbed at a 0.25-micron filter. Beef extract (3%), pH 9, eluted 85-95% of the adsorbed viruses and organic flocculation at pH 3.5 permitted to reconcentrate the viruses in 1/20 of the elution volume with a 50-72% efficiency. The overall efficiency of the technique for 100 ml to 1000 l of the different types of water using 10(2) to 10(6) PFU was 38 to 58%.

Fresh Water↗

PubMed1978

Enzyme-linked immunosorbent assay for the detection of antibodies to pneumonia virus of mice in rat sera.

An enzyme linked immunosorbent assay (ELISA) was established to detect rat serum antibodies to pneumonia virus of mice (PVM). Vero cells infected with the virus were absorbed to the surface of microplates, and the presence of antibodies in the sample evaluated were demonstrated by the subsequent use of goat anti-rat immune globulin G conjugated to peroxidase and by specific substrate. The results indicated that antibodies against pneumonia virus of mice could be detected in rat serum with the ELISA procedure. The results were reproducible, and the method was approximately eight times more sensitive than the hemagglutination inhibition procedure.

Animals↗

PubMed1975

Diagnosis of rubella virus infections. I. A comparison between Vero and BHK-21 cells for the detection of specific IgG and IgM antibodies by immunofluorescence.

Vero cells were more suitable then BHK-21 cells for the detection of rubella-specific IgG antibodies because the nonspecific fluorescence was minimal. However, BHK-21 cells were found more sensitive than Vero cells for the detection of rubella-specific IgM antibodies.

Adult↗

PubMed1975

Diagnosis of rubella virus infections. II. A comparison between incident and transmitted light fluorescence for the detection of specific IgM antibodies.

The fluorescence obtained with an incident light system is higher than that obtained with a transmitted light system. Examination time is reduced and the strain on the eyes, after long periods, is reduced. However, the results are the same whatever the system used.

Animals↗

PubMed1975

[Rubella virus. III. Purification of infected or non-infected Vero cell membranes].

Separation of Vero cell membrane in a discontinuous sucrose gradient reveals five fractions. After infection a sixth fraction appears. It contains virioins but mostly modified membranes with subunits 5-6 nm in diameter, probably the hemagglutinin. None of the enzymes used was associated with this fraction. No modification of the other fractions was observed after infection.

Acid Phosphatase↗

PubMed1975

[Rubella virus. I. Morphology and structural proteins].

Degradation of purified rubella virus by heat treatment (37, 45, or 56 degrees C) revealed the following structures. The viral envelope, a modified cellular membrane, bears spherical subunits, 5-6 nm in diameter, hexamers, or pentamers. Two glycoproteins, VP-2 (50 000 daltons) and VP-3 (63 000 daltons), are associated with the envelope. The nucleocapsid if formed by the condensation of the viral ribonucleic acid on acentral structure 10 nm in diameter. Only one protein, VP-1 (35 000 daltons) is present in the nucleocapsid. Similarity between rubella virus and Togaviruses is discussed.

Cell Membrane↗

PubMed1975

Correlation between the serum neutralization test and the indirect immunofluorescent test for the detection of specific antibodies to infectious bovine rhinotracheitis virus.

Comparative titrations show that immunofluorescence on infected rabbit kidney cells is relatively as sensitive as the neutralization test for the detection of antibodies to the infectious bovine rhinotracheitis virus. When calf testis cells infected with this virus are used for the detection of antibodies by the indirect immunofluorescent test nonspecific staining is high. This nonspecific reaction is absent when rabbit kidney cells are used.

Animals↗

PubMed1975

[Rubella virus. II. Replication in Vero calls and effects of actinomycin Dand cycloheximide].

Budding at the plasmic membrane is the primary mode of production of rubella virus in Vero cells. Intense cytopathic effect is observed even if only 10% of the cells are infected. Actinomycin D has little effect on the multiplication of rubella virus but cycloheximide inhibits its growth. This inhibitiion is probably due to the reduction of cellular protein synthesis and not to a direct action of the inhibitorson the virus multiplication. Viral proteins in infected cells have not been demonstrated. The presence of a viral substance inhibiting normal cellular synthesis is discussed.

Animals↗

PubMed1974