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L W Hedgecock

Publications and source records attributed to L W Hedgecock.

7 recordsLinked to original sources
PubMed1975

Resistance-enhancing compound from Mycobacterium tuberculosis.

A soluble, high molecular weight, resistance-enhancing compound was isolated from Mycobacterium tuberculosis by fractionation of a dimethylsulfoxide extract of the organism with n-decyl alcohol. The compound contained carbohydrate, protein, fatty acids, and phosphorous. Resistance enhancement was nonspecific in that protection was afforded toward infection with Klebsiella pneumoniae as well as M. tuberculosis. The compound enhanced the rate of clearance of carbon from the blood of mice and depressed the immune response of animals to injected sheep red blood cells. No manifestations of toxicity was exhibited by the compound.

Adjuvants, Immunologic↗
PubMed1970

Complexing of fatty acids by Triton WR1339 in relation to growth of Mycobacterium tuberculosis.

Mycobacterium tuberculosis grew in the presence of toxic concentrations of free fatty acids when an adequate amount of triton WR1339 was added to the medium. Triton produced a solubilizing effect on turbid suspensions of fatty acids, indicating the formation of a detergent-lipid complex. Oleic acid complexed with triton served as a source of carbon for growth of M. tuberculosis.

Fatty Acids↗
PubMed1969

Pathogenicity of the Trudeau strain of Mycobacterium sp. 607 for mice.

A study was made of the pathogenic properties of the Trudeau Culture Collection strain (T-67) of Mycobacterium sp. 607 for mice. The organism was highly pathogenic for CF1 mice upon intravenous injection. The animals succumbed soon after intravenous injection of a 14 x 10(6) viable cellular units. The T-67 strain proliferated in the kidneys of the animals but was unable to reproduce in the lungs, liver, and spleen. Destruction of the organisms in the latter organs commenced 24 hr after injection. Tissue bacterial counts showed that the mycobacteria were similarly destroyed in the kidneys after an interval of from 7 to 9 days after injection of the organisms. Histopathological examination of the tissues indicated that the lethal effects of the organism were due primarily to kidney damage. The liver, lungs, and spleen were similarly involved but to a lesser degree. The unique characteristics of the T-67 strain of Mycobacterium sp. 607 are discussed.

Animals↗
PubMed1968

Nutritional characteristics of the atypical mycobacteria.

The ability of Mycobacterium kansasii and groups II and III of the atypical mycobacteria to utilize oleic acid, as well as selected carbohydrates and other compounds, as sources of carbon for growth was compared with that of the H37Rv and H37Ra strains of M. tuberculosis. The highest rate of growth of all of the mycobacteria examined occurred in the medium containing oleic acid as the carbon source when single substrates were tested. The H37Ra strain of M. tuberculosis and all of the atypical mycobacteria examined, except the P-8 strain of M. kansasii, displayed a deficiency in ability to utilize glucose for growth. The deficiency was manifested as delayed appearance of growth, suboptimal growth, or complete inability to utilize the sugar. Variant substrains of organisms that possessed an enhanced ability to utilize glucose for growth were isolated from representative strains of M. kansasii and groups II and III atypical mycobacteria inoculated on modified Kirchner glucose-agar and incubated for an extended period of time.

Acetates↗
PubMed1966

Dietary influence on innate and acquired resistance to tuberculosis.

Hedgecock, Loyd W. (Veterans Administration Hospital, St. Louis, Mo.). Dietary influence on innate and acquired resistance to tuberculosis. J. Bacteriol. 92:439-445. 1966.-The pattern of deaths of CF1 mice maintained both on a defined ration and on commercial chow, and infected with the H37Rv strain of Mycobacterium tuberculosis was compared with that of animals infected with four wild strains of tubercle bacilli as well as with the Vallée and Ravenel strains of M. bovis. All infected animals fed the defined ration died at a slower rate than those fed chow. The dietary effects were most evident in the groups of mice infected with the human strains of M. tuberculosis at reduced dose levels. Under these conditions, a decrease in rate of death occurred in the infected mice fed the defined ration at approximately 3 weeks after infection. Deaths in the animals infected with the bovine strains and fed the defined ration were distributed normally. Interval counts of the number of tubercle bacilli in the lungs of mice infected with a reduced dose of the H37Rv strain of M. tuberculosis showed that in vivo growth of the organisms was inhibited at 2 weeks in the animals fed the defined ration and at 3 weeks in those fed chow. Nonviable vaccines prepared from the H37Rv human strain and from the Ravenel and Vallée strains of M. bovis were ineffective against infection with the bovine strains. All vaccines were effective against infection with the H37Rv strain of M. tuberculosis.

Journal Article↗