Portal de Periódicos da CAPES

THE NATURE OF ANTITUBERCULOUS ACTION OF SULFISOXAZOLE. REPORT I

1958; Karger Publishers; Volume: 6; Issue: 3 Linguagem: Inglês

1421-9794

Michio Tsukamura, Yo Noda, Masakuni Yamamoto,

Pneumocystis jirovecii pneumonia detection and treatment

It is well known that sulfathiazole represents a marked in vitro tuberculostatic action (DOMAGK)'). Recently, TSUKAMURA reported that 3,4-dimethy1-5sulfanilamide-isoxazole (sulfisoxazole) has a tuberculostatic activity similar to sulfathiazole and the drug prevents the in vitro emergence of streptomycin resistance and isoniazid resistance as well as sulfathiazole2.3. NAIT04), SAITO, et al.5), and USHIBA, et alo. utilized the combination of isoniazid and sulfisoxazole for treatment of pulmonary tuberculosis and reported that isoniazid-sulfisoxazole therapy gave a marked clinical effect on tuberculous patients. Therefore, it appears desirable to make clear the nature of tuberculostatic action of sulfisoxazole. The present paper concerns with this problem. Materials and Methods Mycobacterium tuberculosis var. hominis, strain H37Rv, was used through the present study. The medium used was TATSUGI-OGAWA's egg medium. The composition of the medium is as follows : Basal solution (1% KH2PO4 and 1% sodium glutamate), 100 ml ; Whole eggs, 200 ml ; Glycerol, 6 ml ; 2% aqueous solution of malachite green, 6 ml. The medium was poured in 8 ml quantities into each tube, 18 x 170 mm. The medium was slanted by sterilization at 88°C for 60 minutes. The length of slants was 11-.42 cm. Sulfisoxazole (3, 4-dimethy1-5-sulfanilamide-isoxazole) used in the study was the one manufactured by Shionogi Co. (Sulfazin). The drug was dissolved by adding with 1% NaOH-solution and added to medium prior to sterilization. Six week cultures grown as discrete colonies of the test strain was used for preparing cell suspensions. The culture was shaken with glassbeads for 10 minutes and suspended with saline. Ten-fold dilutions were made of the cell suspension and 10° (the original suspension)-to 10-6-dilutions were prepared. Appropriate dilutions were utilized for inoculation. Inoculation was made with a large whirled loop delivering 0.02 ml onto medium slants, for the method of inoculating cell suspensions with the whirled loop had been found by us to give the smallest variation of colony numbers7). Generation time was calculated according to YOUMANS and YOUMANS8). The generation time was found by substituting the growth rate constant, K, into the formula : G=log 2/K. To estimate the growth rate constant, five sets of tubes were inoculated with each of the 10-'-to 10dilutions and one set consisted of five tubes. The inoculated tubes were incubated at 37°C and examined daily at approximately the same time, and a record was kept when growth was first noted. Results 1) The effect of sulfisoxazole on the growth rate of Mycobacterium tuberculosis. The generation time was measured on various concentrations of sulfisoxazole, and the results are shown in Table 1 and Figure 1. As shown in the figure, a linear relationship has been found between the generation time and the sulfisoxazole concentration, and the generation time has been found to be a function of the sulfisoxazole concentration. The results indicate that the nature of action of sulfisoxazole on M. tuberculosis is to delay the generation time. It is very probable that the delayed generation time results from the inhibition of synthesis of new cell material as purine derivatives, etc.