In experiments of serological neutralization of T2 bacteriophage, it was found that the rate of neutralization of the T2 by an immune rabbit serum depends upon the bacterium used for assay. However, the choice of host used in growing the phage stock has no effect.
Neutralization velocity constant of T2 assayed with each of four different cells, E. coli B, Shigella flexneri BIII, BI and KA, was about 200-380 min.^-1, 430-520 min.^-1, 620-730 min^-1. and 800-900 min^-1. respectively.
A possible inhibitory action of the anti-phage serum on the indicator cells was excluded by an experiment in which the antiserum was added to the agar layer of the assay plate.
These findings rules out the possibility that T2 phage stocks are composed of four different classes of monovalent phages each being able to invade only one of the four host cells. It would seem, rather, that each T2 particle has a complex antigenic structure in its site of attachment which is neutralized differently by the corresponding antibodies.

View full abstract

No morphological difference was revealed by electron microscopy between or among different strains of phage ε¹⁵ which were obtained from S. newington, S. selandia, S. newbrunswick, S. cambridge and S. kinshasa of group E₂, and S. canoga, S. illinois and S. thomasville of group E₃.
The sperm-shaped particles of phage ε¹⁵ have a spherical head (54-58mμ in diameter) with an elongated tail (20×162-186mμ).

View full abstract

In this communication a report is made on the effects of animal viruses on the endogenous respiration of host tissues.
The results obtained are summarized as follows.
When the metabolism of tissues is to be studied by means of the Warburg manometer, it would be worthy to discuss whether the endogenous respiration increases or derceases.
The endogenous respiration can either increase or decrease with virus or RDE. Therefore, the present writers believe that the tendency is an absolute, non-variable state which fluctuates according to the germinal layer of host tissues.
The ectodermal host tissues (brain) have a tendency to decrease and the mesodermal and endodermal host tissues (erythrocytes, lung and liver) have a tendency to increase the endogenous respiration.
All these findings would indicate that a common component exists between the substrate of endogenous respiration enzyme and the important part of receptor of host tissues.

View full abstract

On 583 children suffering from acute infection of the respiratory tract who were found in Tokyo area during the period of 2 years from January 1956 to February 1958 (67 single sample cases and 516 paired sample cases) 1, 194 specimens were collected, and they were examined for HVJ complement fixation test, HVJ hemagglutination inhibition test, cold hemagglutination, MG streptococcus agglutination, influenza A and B hemagglutination inhibition test and adenovirus and ornithosis complement fixation test. Thus, 46 paired sample cases were diagnosed as HVJ infection. Suspected HVJ cases were 6 of the paired sample cases and 10 of the single sample cases.
The rise in the HVJ complement fixing titer began usually at the end of the 1st week of the disease, and reached the maximum at the end of the 2nd week. It showed a tendency of declining thereafter.
The HVJ hemagglutination inhibition titer of the RDE untreated specimens from 26 out of 46 HVJ infection cases showed a tendency of rise after the 2nd or 3rd week. The rise was found slightly later compared with that of the complement fixing antibody titer. In the RDE treated specimens from 20 cases, as the result of the destruction of the unspecific agglutination inhibiting substance, the fluctuation in the antibody was found at the lower level compared with that in the untreated cases. It reached the maximum at the end of the 1st or 2nd week, and seemed to demonstrate a tendency to decline gradually thereafter.
As the result of the cross determinations of the complement fixing titer and the hemagglutination inhibiting titer on 5 clinically definitely diagnosed mumps cases and 5 HVJ infection cases, no correlation was found between the two diseases.
When the distribution of the antibody against Obayashi strain of HVJ in the healthy school children of Japan was investigated, the HVJ complement fixing antibody titer was less than 2 fold dilution in all of the 138 cases, and the HVJ hemagglutination inhibition titer of the same specimens untreated with RDE showed 32-256 in 80 and less than 32 in 58 out of 138 cases. In the cases with RDE treatment, the same cases showed 16-128 in 13 and less than 16 in 28 out of 41 cases.
In view of the above, the HVJ infection was considered to be fairly universal among the children of Japan.

View full abstract

During the course of the studies on the children's cold which occurred in Tokyo area from January, 1956 to February, 1958, the epidemiology and clinical picture of the 46 casese, the diagnosis of HVJ infection of which was serologically confirmed, were observed. The following results were thus obtained.
1) When the seasonal pattern of the prevalence of HVJ infection was investigated, a clear tendency of greater prevalence in winter both in the absolute number of cases and in the frequency as against the total number of cases of cold was recognized. In other words, the relative frequency of HVJ infection against the total number of cases of cold in winter was 12 cases (13.3%) out of 90 which were found during the period from January to March, 1956, and 11 cases (22.4%) out of 49 which were found during the period from December, 1956 to March, 1957, and 13 cases (10.9%) out of 119 which were found during the period from December, 1957 to February, 1958. In summer, it was 2 cases (3.3%) out of 60 during the period from June to September, 1956, and 3 cases (3.3%) out of 92 during the period from June to September, 1957. The greater prevalence of HVJ infection during winter is a matter of great interest when considered from the reports on the past epidemic of HVJ pneumonia among new-borns and infants which occurred in Tokyo area, because it suggests difference by area and season.
2) The pattern of occurrence by age of HVJ infection was next investigated. During the stage of infant of below 1 year of age, it was 5(7.6%) out of 66 cases, during the stage of child of 1 to 5 years of age, 20(8.5%) out of 236 cases, and during the primary school age (6 years old and above), it was 21(7.5%) out of 281 cases. Thus, no difference by age of the HVJ infection was noted.
3) The pattern of occurrence of HVJ infection by sex was next studied. The number of male cases was 19 or 41.3% and that of female cases was 27 or 58.7%. Thus, no significant difference between the sexes was recognized.
4) The HVJ infection cases were classified by the clinical pictures. There were 13 cases (28.3%) of acute pharyngitis, 4 cases (8.7%) of acute pharyngo-tonsillitis, 1 case (2.2%) of acute pharyngolaryngitis, 24 cases (52.2%) of acute bronchitis and 4 cases (8.7%) of bronchopneumonia. When these types were observed by age groups, it demonstrated during the infants stage acute bronchitis or bronchopneumonia in all cases, while there were no case showing pneumonia among primary school children, but about half of them showed acute pharyngitis or tonsillitis. Thus, difference in the clinical picture was clearly shown by various age groups.
5) Excepting severe cough, no particularly different findings were observed when each of the symptoms of HVJ infection was compared with those of the ordinary cold. In all cases, the prognosis was favorable. As complications, 2 cases of acute nephritis, 1 case of recurrent nephritis, 1 case of aggravated nephrosis, 1 case of acute otitis media and 1 case of recurrent-vomiting, totalling 6 cases (13.0%) were recognized. These complications were all ameliorated or cured by treatment.
6) In the chest X-ray pictures, transient exsudative pictures which are indistinguishable from those observed in the cases of the primary atypical pneumonia were recognized in 10 out of 27 cases examined.

View full abstract

1. Ectromelia virus can propagate in cultures of strain L cells.
2. The cytopathogenic effect can be used for the titration of virus.
3. The virus produces two kinds of inclusion bodies in L cells, named “B” and “A” bodies.
4. In this system, the specific complement fixing antigen was detected 5hours, the inclusion bodies appeared 6hours, and the infective virus was found 8hours after infection.

View full abstract

Methods of propagating Newcastle disease virus in rocking, rolling and medium-changing cultures with adult chicken spleen were studied in comparison with the conventional static culture method. The main results are as follows.
1. Rocking effected no better results in the propagation of the virus.
2. Rolloing made the end titer of the virus a little higher.
3. The change of medium resulted in a remarkable increase of the end titer of the virus. Especially it was true in rolling cultures with relatively high concentration of tissue.
4. Throughout the whole study, the culture method most fitted for virus propagation was found to consist of the following steps. The tissue weighing 10 per cent of the amount of culture medium was fixed on a piece of Japanese rice paper and placed in a culture tube or bottle with cotton plug. The culture was made under conitnuous rolling, and the medium was renewed twice a day. By this method LD₅₀ titer (-log₁₀) reached 7.5 in whole culture and 8.5 in cultured tissue.

View full abstract

The present paper describes some new host-range phenotypes of T4 phage, and their genetic control, regarding to the infectivity Of the virus against two different Shigella flexneri (which are originally resistant to T4), BI and BIII strains.
Fine structure of some genetic regions of T4 phage which control different host-range phenotypes of the phage was investigated by means of recombination procedure.
It has been demonstrated that the inheritance of the host-specificity of T4 is controlled by many genetic loci distributed fairly widely in T4 genome. They have been found being clustering at several different genetic regions, and all the mutations arising anywhere within one of these regions lead to similar phenotypic effect, whereas each region controls different phenotypes, respectively.
Some of the h mutants have a very favorable property which allows the study on the fine genetic structure of the h region by a selective technique. The smallest recombination value so far as observed was about 0.05-0.1 per cent recombination units, suggesting that the size of the elementary unit controlling the host-specificity of the virus is not larger than roughly 10 nucleotide pairs length.
All the h mutants descrived here did not invade K12 (λ)/4 and B/4 bacteria.

View full abstract