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T M Buchanan

Publications and source records attributed to T M Buchanan.

84 records · Page 5Linked to original sources
PubMed1973

Studies on gonococcus infection. 3. Correlation of gonococcal colony morphology with infectivity for the chick embryo.

Comparable numbers of types 1, 2, 3, and 4 gonococci were placed on the intact chorioallantoic membrane of 236, 10-day old chick embryos. Types 1 and 2 organisms produced infection and could be cultured from chorioallantoic fluid 2 days later significantly more often (69%) than types 3 and 4 organisms (12%, P < 0.001). This confirms in an animal model the same correlation between colony types and infectivity observed in human volunteers and suggests that types 1 and 2 gonococci possess a fundamental virulence characteristic which is absent from types 3 and 4 organisms. Gonococcal infection of the chick embryo chorioallantoic cavity remains a useful model somewhat analogous to localized gonococcal infection in man.

Animals↗
PubMed1973

Quantitative determination of antibody to gonococcal pili. Changes in antibody levels with gonococcal infection.

Gonococcal pili, pure by the criteria of electron microscopic examination and polyacrylamide gel electrophoresis in sodium dodecyl sulfate, have been prepared by repeated cycles of precipitation with 0.1 M MgCl(2), followed by dissolution in 0.01 M Tris pH 8, 0.01 M NaN(3). Using a fluorescein-conjugated antibody prepared to pili from a single strain, pilar antigen(s) was found to be present in each of 18 strains of gonococci tested, and absent from strains of pilated meningococci, nonpathogenic Neisseria sp., and Escherichia coli. Purified pili, labeled with (125)I were used in an antigen binding assay to quantitatively measure antibody to pili in rabbit sera and in 561 human sera. The range of antibody activity for 133 persons unlikely to have experienced gonorrhea was 0.1-1.6 mug/ml with a geometric mean of 0.5 mug/ml. This geometric mean antibody activity was significantly lower than the geometric mean for asymptomatically infected males (1.0 mug/ml, P < 0.002), males with symptomatic gonococcal anterior urethritis (1.6 mug/ml, P < 0.001), or asymptomatically infected females (4.2 mug/ml, P < 0.001). Antibody appeared in elevated levels (> 1.6 mug/ml) 2-3 wk after infection and returned toward control levels 1 or more months after treatment. Antibody levels higher than 1.6 mug/ml were found in 26 (50%) of 52 males with gonococcal anterior urethritis, in 10 (33%) of 30 males with asymptomatic urethral infection and in 50 (89%) of 56 asymptomatically infected females. In a high-risk group of 103 females for whom culture results and antibody to pili were compared, 58 (57%) had elevated antibody levels to pili and 86% of the infected females were within this seropositive group. The antigen binding assay may provide a means to detect asymptomatic gonococcal infection in women.

Adolescent↗
PubMed1971

Polyacrylamide gel electrophoresis of Corynebacterium diphtheriae: a possible epidemiological aid.

In this preliminary study, the use of polyacrylamide gel electrophoresis as an aid in the characterization of Corynebacterium diphtheriae was evaluated and a standardized method was developed. The electrophoretic patterns of 17 gravis, 14 mitis, and 2 intermedius types of C. diphtheriae were compared with the electrophoretic patterns of 5 Robinson and Peeney stock gravis serotype strains. Each of the 5 stock serotype strains had different electrophoretic patterns, although some common bands were present. The 17 gravis strains isolated in the United States showed patterns identical to those of the stock gravis serotype II strain. The 14 mitis strains examined produced 6 different electrophoretic patterns, irrespective of geographical location. One mitis pattern corresponded with the pattern of gravis serological type II. The two intermedius strains examined had identical electrophoretic patterns that resembled the pattern of gravis serotype IV. Polyacrylamide gel electrophoresis of C. diphtheriae strains may prove to be a useful epidemiologic tool in establishing the distribution and occurrence of various C. diphtheriae types.

Bacteriological Techniques↗