Tho virus isolation and the histo-pathological investigation were carried out by means of Encephalotomy from fatal cases with Japanese B Encephalitis admitted in Kyoto Municipal Hospital since 1960 through 1962.
1) The virus was isolated successfully in suckling mouse brain by intracerebrat inoculation of brain tissue from the fatal patients by means of surgical drill and horseliver punction needle without to open the scalp of the patients.
2) Japanese B Encephalitis virus was detected from the 6 out of the 11 cases. Six cases were positive among 8 cases which died within one week after the onset.
3) The virus isolated from a fatal case was identified by means of HI test against immune guinea pig serum and patient serum.
4) The histo-pathological diagnosis could be made from the brain tissue, in which characteristic findings of encephalitis were noticed, of a patient even who was virus negacive case.

View full abstract

The ultrastructure and developmental process of Japanese B encephalitis virus were studied by electron microscopy in tissue culture of porcine kidney stable (PS) cells infected with the Mukai strain of Japanese B encephalitis virus. The virus and PS cells were kindly supplied by Dr. Y. Kanda Inoue at the Virus Institue of Kyoto University. PS cells were cultivated in bottles containing 10% calf serum and 0.5% lactalbumin hydrolyzate in Earle's balanced solution. Titration of cell-associated virus was estimated by cytopathic effect. At various intervals following infection, the cells were fixed in buffered 1% osmium tetroxide solution, embedded in methacrylates and cut on a Leitz ultramicrotome. After the sections were stained in saturated uranyl acetate solution, they were observed in the Hitachi type HU 11 electron microscope.
Japanese B encephalitis virus particles were hexagonal in thin sections and approximately 40 mil in the longest diameter, composed of the outer membrane, 30 A in thickness, viroplasm, 30 A in thickness and an electron-dense nucleoid, 25 mit in diameter. After the virus particles developed on the wall of the cytoplasmic vacuole, they were densely packed in the vacuole usually in random arrangement and rarely in crystalline arrays. The vacuole containing the virus particles gradually migrated to the cell surface and liberated the particles to the exterior of the cell through a narrow canaliculus which was formed between the vacuole and cell surface.

View full abstract

From the author's experiences of 16 cases of typhoid and paratyphoid fever carrier state, its developmental mechanism and therapy were concluded as follows:
1) Gallstones are involved in development of carrier state. Foreign bodies and locus minoris caused by them let pathogenic agents settle down, thus inducing carrier state.
2) Therapy is dependent upon the state of infections focus.
i) Cases where infectious focus exists only in gall bladder are most frequently encountered and healed mostly by cholecystectomy.
ii) Cases where foci exist in gall bladder, choledochus and liver near to choledochus are infrequently encountered. A part of them can be controlled by cholecystectomy and drug administration, while others are incurable.
iii) Cases where foci exist in deep parts or in wide area of the liver are rare and intractable.

View full abstract