38年および39年結核実態調査で分離された人型結核菌の毒力に関する研究 : 第I編マウスに対する毒力

概要

論文の詳細を見る
The virulence of forty three strains of M. tuberculosis isolated from tuberculous patients who were discovered at “Tuberculosis Prevalence Survey in Japan” (Japanese Ministry of Health and Welfare, 1963 and 1964) was examined. All the patients under these studies were new cases discovered at the Survey and had no history of antituberculous treatment. The virulence of the bacilli isolated from these patients was compared with that of two English strains and eight Indian strains from Dr. Mitchson. Also the standard strain Kurono was examined in these studies. The bacilli were cultured on egg madia at the isolation and subcultured on the same media for drug sensitivity tests. The bacilli grown on the control tubes were planted in Dubos liquid media and the bacterial suspension was obtained. The various bacterial suspensions were standardized to a given optical density. Each animal was infected with 0.1mg (wet weight) of bacilli. Ten female mice of dd strain were infected intravenously with each strain of bacilli. The death rate up to 8 weeks after infection was observed. All the survived mice were sacrificed at the 8 th week, the tuberculous change was observed, and the degrees of tuberculous pulmonary involvements were judged macroscopically. The weight of lungs and spleens was measured at the same time. The results were as follows: 1. The viable unit of bacilli used in the infection was almost the same in number in all the strains examined. The average unit was 38.5×105 (standard deviation 13.1×105) (Table 1 and Fig. 1). 2. The death rate of mice infected with 0.1mg of each strain was varied from 100% to 0% (Table 1 and Fig. 2). 3. The degree of tuberculous involvement in lung used in these experiments was graded as follows: no lesion…0; minute tubercles less than 20 in number…1; minute tubercles more than 20 in number…2; minute tubercles mixed with some tubercles larger than 2mm in diameter…3; minute tubercles mixed with many tubercles more than 2mm in diameter…4; the surface of the lung all studded with many tubercles from one to several mm in diameter…5; in the group where tuberculous death was observed from 4 to 5 weeks after infection, one point was added mechanically to point 5, i.e. 6; when dea th was observed from 2 to 3 weeks, 2 points were added to point 5, i.e. 7. The average degree of tuberculous involvement in lung of each strain was varied from 7.1 to 2.3 (Table 1 and Fig. 3). If the difference of the average degree of tuberculous involve ments was more than one, a significant difference could be confirmed statistically. 4. The weight of the lung and its ratio to the body weight were correlated with the degree of tuberculous involvement in lung (Fig. 4). To compare the degree of tuberculous changes with the lung weight, weighing of the lung must be carried out after removing lymph glands, and without blood congestion. In Fig. 4, only the results of experiments were demonstrated where the lungs were weighed as above mentioned. 5. INH resistant strains (primary resistant cases) showed low virulence to mice (Table 2). Comparison of English and Indian strains with Japanese strains will be discussed in the further reports.

38年および39年結核実態調査で分離された人型結核菌の毒力に関する研究 : 第I編マウスに対する毒力

スポンサーリンク

概要

著者

関連論文

スポンサーリンク