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Biomedical subjects

J R Ward

Publications and source records attributed to J R Ward.

At least 163 records · Page 9Linked to original sources
PubMed1968

Hemolysin and peroxide activity of Mycoplasma species.

Various methods for the detection of hemolysin production by Mycoplasma species were compared. Inoculation of blood-agar by the push-block method and by use of concentrated mycoplasma cell suspensions was compared with the agar-overlay technique. The preferred method was direct surface inoculation of concentrated suspensions onto the blood-agar. Among the conditions tested, refrigeration of 48-hr cultures gave the best results. A wide variety of mycoplasma species were tested for hemolytic activity towards rabbit, sheep, guinea pig, duck, and chicken bloods. Guinea pig erythrocytes were found to be the most susceptible to lysis by mycoplasma, and rabbit erythrocytes were found to be the least susceptible. A sensitive technique for the detection of peroxide production by mycoplasma strains, employing agar containing benzidine and sheep blood, was used. With this method, peroxide production could be correlated with hemolysis on blood-agar. Peroxidase and catalase inhibited both the benzidine reaction and hemolysis. It was concluded that the major hemolysin of the Mycoplasma species examined is a peroxide.

Bacteriological Techniques↗
PubMed1967

Characterization of mycoplasma strains from cats.

Mycoplasma strains (B1, B2, CS, and S1A) were isolated from the saliva of normal cats. These were compared with a strain (CO) isolated from the eye of a cat with severe conjunctivitis. On the basis of morphology, biochemical reactions, and antigenic composition, two distinct species were recognizable. Strains CO, B1, and B2 were antigenically unrelated to the other species tested; strains CS and S1A possessed antigenic components in common with Mycoplasma arthritidis, M. salivarium, M. hominis, type 1, and M. orale, types 1 and 2. It was tentatively suggested that the two cat species be called M. felis and M. gateae, respectively.

Animals↗
PubMedDate not supplied

DNA polymerase activity of cultured rheumatoid synovial cells.

Cultured synovial cells from 8 patients with rheumatoid arthritis (RA) and 7 subjects without joint disease were assayed and comapred for RNA-directed and DNA-directed DNA polymerase activity. No activity was found in either RA or control specimens using a synthetic RNA template that specificically detects oncornavirus RNA-directed DNA polymerase. The DNA-directed DNA polymerase activity of RA specimens was increased (P less than 0.10) in the high-speed pellet fraction of cell lysates. The possible relationship of these finding to virus infection in RA is disscussed.

Adult↗
PubMedDate not supplied

Studies on the infectious etiology of human rheumatoid arthritis. II. Search for humoral and cell-bound antibodies against mycoplasmal antigens.

A total of 29 rheumatoid patients and 19 nonrheumatoid patients were tested for evidence of present or past infection by M pneumoniae, M hominis, M fermentans, M arthritidis, M pulmonis, and M hyorhinis. The techniques of lymphocye transformation, metabolic-inhibiting antibody test, and mycoplasmcidal antibody test indicated no significant difference in the response of rheumatoid as opposed to nonrheumatoid patients.

Antibodies, Bacterial↗
PubMedDate not supplied

Hematologic and serologic studies in 6-sulfanilamidoindazole arthritis.

6-sulfanilamidoindazole (6-SAI), an antibacterial sulfonamide, is known to cause an acute, self-limited inflammatory reaction in the hind paws of older rats. Administration of 6-SAI results in hyperfibrinogenemia which precedes the onset of clinical arthritis. The hyperfibrinogenemia is associated with the prolongation of dilute blood clot lysis times, appearance of heparin-precipitable fibrinogen, elevations in fibrin degradation products, and complement titers and serum electrophoretic pattern changes that consist of decreased albumin concentrations and increased beta globulin concentrations. Alterations in 6-SAI medicated young rats are less marked and require higher doses.

Administration, Oral↗