During the period from May to December 1962, stool samples of 60 healthy and 87 diarrhetic infants collected in Tottori city and the suburbs were examined for enterobacterial flora. The results were summarized as follows.
1) Between healthy and diarrhetic infants, there was some difference in the isolation rate for each of the non-pathogenic enterobacteriae with the exception of Proteus and the relatives.
2) Shigellae were detected in 5.7 per cent of the diarrhetic infants. Types of the bacteriae isolated were Sh. flex. 3a (in 4 cases) and sonnei (in 1 case).
3) Pathogenic coli were detected in 6.7 per cent of healthy and 10.3 per cent of diarrhetic infants. Types of the coli were O-26 (in 1 case), O-44 (in 6), O-75 (in 4) and O-11 1 (in 2 cases).
4) Dyspeptic infants presented wide spectra of enterobacterial flora, and the flora of infants suffering from the other diseases consisted mainly of E. coli.
5) St. aureus was detected in 5.0 and 3.4 per cent of the healthy and diarrhetic infants, respectively and St.epidermidis in 36.7 and 32.3 per cent of the healthy and diarrhetic infants, respectively.

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Cerebellar tissues from puppies and kittens, 1 to 15-day-old, as well as from human embryos were cultivated on a coverslip by the roller-tube technique. Culture medium consisted of 50% human cancerous ascitic fluid, 5% chick embryo extract, 45% Gey's balanced salt solution, 300 mg% glucose and 1, 000 u/ml penicillin. Temperature of incubation for cellular growth was 37°C. Viruses used were: JBE G1 strain, of the 240th to 245thmouse brain passages; JATH 260 strain, of the 1st to 4th mouse brain passages; K. Inoue strain, of the 2nd or 3rd mouse brain passages; and Negishi strain virus, a member of the Russian Spring-Summer encephalitis group, of the 7th to 10th mouse brain passages. Temperature of incubation following virus inoculation was 34°C
All of the viruses tested multiplied in the cerebellar tissue cultures. The grades of viral multiplication, however, were different in each virus strain-culture system combination. JATH strain JBE virus multiplied well in puppy and human embryonicerebellar cultures; the highest virus titers in fluid phase (mouse-intracerebral LD₅₀/0.02 ml) were about 10⁶, which usually were attained 5 to 7 days after inoculation of virus. Contrarily, growth of K. Inoue strain virus was inferior in every of the culture systems employed, the highest titers in fluid phase being 10² to 10^2.5. Viral growth in kitten cerebellar tissue cultures was generally slighter than that in puppy cerebellar tissue cultures. Difference in the affinity between virus strains and nervous tissue cultures was evident.
In the virus-infected cultures stained by either Bodian or Nissl method, the Purkinje cells exhibited degeneration. Some of the characteristic changes revealed by the Bodian stain were as follows:(1) In, the mild infection stage, the nuclei changed the original staining properties and contained unusual granules; the neurofibrils both in the cell body and in the dendrited staines rather roughly; branches of the dendrites were shortened or reduced in number; the neurites showed abnormal appearance such as breaking, swelling, serpentine turnings, etc. (2) In the advanced infection stage, the nuclei were disintegrated into masses of debris and the neurofibrilar patterns were completely lost; the dendrites became rudimentary; the neurites were broken and could not be fully traced. In Nissl stained preparations, the tigroid substances lost their original staining ability, and vacuoles of various sizes were seen in the cytoplasm.
These alterations were prevented by mixing the viruses with the specific anti-viral antisera prior to inoculation. Morphological changes noted in the Purkinje cells in cultures which had been subjected to disadvantageous conditions such as prolonged incubation without changing medium or incubation in higher temperatures, were apparently different from the changes that occurred inevitably in the virus-infected cultures. It was concluded, therefore, that the degeneration of Purkinje cells observed as above was caused specifically by the viruses. Virological and neuropathological significances of the findings are discussed.

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