The antigenic activities of tuberculin fractions to elicit an anaphylatic reaction in vitro were examined using intestinal strips of guinea pigs sensitized with dead tubercle bacilli suspended in liquid paraffin oil. All fractions were purified according to the Seibert's procedure.
Of fractions tested, antigenic activities of the polysaccharide I fraction was strongest and the next strongest was protein A fraction. Protein B, C and polysaccharide II fractions had relatively low activity.
Repeated fractionation of the protein A fraction into protein and polysaccharide portions disclosed that the latter was much more active.
No great difference in activity was found between the fractions obtained from unheated culture filtrates and the corresponding fractions from heated filtrates.
The polysaccharide I fractions of human type tubercle bacilli and BCG showed no distinct type specificity.

View full abstract

(1) The same individuals were inoculated with Enders' and its control antigens at the same time. Erythema exceeding 10 mm in diameter was not found with the control antigen; 14.8 per cent and 18.2 per cent of these showed positive reaction with the E antigen after 24 and 48 hours, respectively. Compared with the results of the HI antibody titration, the positive skin test with the E antigen was considered to have a specific relation to the previous mumps virus infections.
(2) As a result of the comparative evaluation of four mumps skin test antigens, the HS and HV antigens were of superior quality, when the positive reactions were assumed to be an erythema exceeding 10 mm in the HS and 15 mm in the HV antigen after 24 hours. Both antigens showed a correlation to the history of mumps virus infection in a significant level of less than 0.01.
(3) In the frequency distribution curve of the size of the erythema, the rate of palpable induration and the process of disappearance of erythema, there were differences between the S and V antigens.
(4) The lyophilization of the skin test antigen was of value for storage.

View full abstract

The skin test by the HS and HV antigens was performed on 516 of 712 individuals belonging to three populations of a different epidemiologic status, and its practicability as an epidemiological tool was evaluated.
1) 85.7 per cent and 74.3 per cent of the positive history group of mumps revealed a positive skin test by the HS and HV antigens, respectively.
2) In the three populations having a different epidemicity of mumps the frequency distribution curves of the size of the erythema by the HS skin test implicated the state of their herd immunity. On the contrary, the HV skin test did not show such a specificity.
3) 5.1 per cent of the positive skin test reactors and 24.1 per cent of the negative reactors were suffering from mumps after the completion of the skin test.
4) It was considered that the positive criteria of both the HS and HV skin tests should be an erythema exceeding 10mm by the 24-hour reading.
5) In the first and second reports several differences were mentioned between the HS and HV skin tests. The HS antigen is considered to be superior to the HV antigen as an indicator for mumps immunity; there exists a reasonable correlation between the blood antibody level and the skin test.

View full abstract

Experiments were done to determine the generation time of M. ulcerans (PD) on 3 types of media, Ogawa's 1% KH₂PO₄ medium, the Kirchner agar and the Dubos medium. The method of determination of generation time was that given by Youmans and Youmans.(3)
The generation time of M. ulcerans (PD) was calculated as being about 42 hours at 33°C and 56 hours at 37°C by the method described above. The generation time of M. tuberculosis (H₃₇Rv) was about 36 hours at 33°C and about 25 hours at 37°C and that of M. muris (Wells) was about 44 hours at 33°C and 33 hours at 37°C.
These experiments showed that the growth rate of M. ulcerans was stimulated at 33°C, whereas that of M. tuberculosis was stimulated at 37°C. The growth rate of M. muris at 33°C resembled that of M. ulcerans, but the growth was stimulated at 37°C.
In the experiments mentioned above, the generation time of H₃₇Rv at 37°C was about 25 hours, and Holmgren and Youmans⁽⁴⁾ calculated the generation time of this strain as 23.08±1.36 hours in the Proskauer and Beck medium at 37°C.
We obtained a value essentially similar to that described by Holmgren et al. and Gutiérrez-Vázquez.⁽⁵⁾
According to the experiments of Leach and Fenner, ⁽⁶⁾ the generation time of M. ulcerans (SF) was below 48 hours in the Dubos medium at 33°C, and our data on M. ulcerans (PD) showed 44 hours in the Dubos medium without serum. The discrepancy may first be due to the strain, secondly to the calculation method.
The results of our experiments at 37°C suggest that the growth rates of M. tuberculosis and M, muris are similar but that of M. ulcerans is half of M. tuberculosis. In the case of 33°C there is an agreement between the growth rates of M. ulcerans and M. muris, but M. tuberculosis showed different data.
Observations made on the correlation between catalase activity and rate of growth revealed that M. tuberculosis shows a slow growth rate and moderate catalase activity, but, in general, avirulent mycobacteria contain a large amount of catalase and their generation rate is high. The catalase activities of M. ulcerans and M. muris are stronger than that of M. tuberculosis, but the growth rate of M. ulcerans is lower than that of M. tuberculosis.

View full abstract

1) Experimental treatment of animals infected by various kinds of pathogenic microorganisms was conducted with mitomycin A and C.
2) Curative effects were observed on leptospirosis and rickettsiosis, and some effects on the infections caused by D. pneumoniae, S. enteritidis and toxoplasma.
3) Both mitomycin A and C showed similar effects on the infection of rickettsia and on other infections, but mitomycin C was more effective than mitomycin A.

View full abstract

1) Experimental treament of various infections of viruses was conducted with mitomycin A and C.
2) The mitomycins showed some therapeutic effect on the infection caused by the large viruses, such as sheep pneumonia virus, but no curative effect on the infections caused by the small viruses, for example, influenza A, Newcastle disease and Japanese encephalitis viruses.
The authors wish to thank Dr. Numata, Dr. Kasahara, Dr. Matsubayashi, Dr. Fukuzumi, Dr. Kasuga and Dr. Nagaki of the Kitasato Institute for their kind helps and Dr. Kamata and Dr. Wakaki of the Kyowa Fermenting Industry Company for supplying us with the mitomycins.

View full abstract

The influence of streptomycin on the reverse mutation of E. coli from auxotrophy to protoprophy was investigated. Cells recovered from cultures of auxotrophic strains were exposed to this agent in a phosphate buffer, or cultured in a broth contaning a subinhibitory dose of the drug. In both cases, the increase of reverse mutation was observed. Prototrophy was not, in general, associated with the resistance to streptomycin. The results mentioned above, together with those reported in the previous papers, led the authors to the conclusion that streptomycin is a chemical mutagen and its effect is non-specific and non-directed.
The authors are indebted to Dr. F.J. Ryan of Columbia University for his advice on this investigation during his stay at the University of Tokyo.

View full abstract

The antigenic structure of five species of the genus Saccharomyces was ex-amined by the slide agglutination method with monospecific and absorbed antisera.
1) S. fragilis, S. marxianus, S. macedoniensis and Zygosacch. marxianus are antigenically identical with C. pseudotropicalis of asporogenous yeasts.
2) S. cerevisiae and S. ellipsoideus are antigenically identical with C. robusta.The species name of S. marxianus and S. cerevisiae should be accepted. The other species name of the genus Saccharomyces mentioned above cannot be recognized, and it is better to have the name of C. pseudotropicalis changed.
The authors wish to thank Profs. T. Akiba and Y. Takahashi for their kind advices and suggestions.

View full abstract

Fractionation of purified diphtheria toxins by means of zone electrophoresis using a starch-supporting medium revealed the presence and distribution of the toxin containing 3200-3300 Lf/mgN. It has been isolated as an electrophoretically homogeneous protein and shown to be 98% pure in terms of percentage of antigen specifically precipitable with the purified antitoxin through the quantitative immunochemical analysis using the I131 trace-labelled antigen.
The toxin preparations containing the Lf values around 2500Lf/mgN which has been considered to be of a sufficiently high degree purity seem to comprise a mixture of the specific toxin containing 3200-3300 Lf/mgN and the accompanying protein antigens with similar physicochemical properties.

View full abstract

1) The selective mechanism of desoxycholate was studied considering a possible relationship to the nucleic acids-extracting effect of desoxycholate, and its principal mechanism was clarified.
2) Viable cell number and oxygen consumption of cell suspensions grown in desoxycholate-containing media decreased during incubation, and this decrease was more remarkable in case of coli strains than in case of dysentery strains. Moreover, addition of citrate promoted this difference.
3) Decrease of viable cell number was parallel to the decrease of stainability of bacterial cells with basic, nucleic acids-staining dyes when the cells were in-cubated in the desoxycholate-citrate medium. And this tendency was also more striking in case of coli strains.
4) The principal mechanism of selective action of the desoxycholate-citrate medium is believed to depend upon the nucleic acids-extracting effect and the resulting bactericidal effect of desoxycholate, promoted by the co-existence of citrate. Coli strains are more sensitive to this action than dysentery strains.

View full abstract