Yoh Nakagawa

EFFECTS OF ANIMAL VIRUSES ON THE ENDOGENOUS RESPIRATION OF HOST TISSUES

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.

STUDIES ON DENGUE VIRUS (XII)

Electron micrographs of dengue viruses of Hawaiian strain and Mochizuki strain, which were adapted to mouse brain and chick embryo have been taken using purified virus materials.Purification methods employed were as follows: (I) Combination of partial purification of the virus adsorption to and elution from erythrocytes and ultracentrifuge, (2) Combination of protamine sulfate precipitation and ultracentrifuge. Studies by electron microscope of purified preparations from infected mouse brain and chick embryo showed that the infective particles of dengue virus were spherical, uniform and aggregate, average 18±2mμ in diameter, and they were considered to be the virus.The smaller particles of about 15mμ in diameter seen in infected mouse brain seemed to be normal components because the similarsized particles were observed also in the normal mouse brain.

PURIFICATION AND CONCENTRATION OF FA STRAIN HEMAGGLUTININ OF MOUSE ENCEPHALOMYEIITIS VIRUS (I)

It has been discovered by Nakagawa and Kodama that FA strain of mouse encephalomyclitis virus agglutinates chicken red cells at 4C when 1.5% CaCl2 solution is used as a reaction medium. The present study concerns the purification and concentration of the virus hemagglutinin by application of the properties of the virus.Therefore, purification of the virus hemagglutinin by means of adsorption to and elution from erythrocytes was attempted. From the result obtained, this procedure was an effective and simple method as in the case of GD VII virus and Influenza virus. Ether extraction of crude, also, is a simple method for removal of nonviral nitrogen. In order to yield more purified hemagglutinin of FA strain, methanol and acetone precipitation methods were employed after ether extraction of virus material and elution of virus from blood cells.The results obtained indicate that a good yield of hemagglutinin of FA strain is acquired by elution from precipitants produced by adding acetone to give a final concentration of 30% to the materials, obtained after extraction by ether and adsorption to and elution from erythrocytes, and keeping the mixture at 4C for 3 hours with occasional agitation.