Fine structure of the fully keratinized hair cuticle in the head hair of the human

The cuticle is composed of five cell layers in the cross section of the hair at a level of 100 mm above the scalp. Intercellular junctions between two cuticular cells are zonulae occludentes (tight junction); they consist of five layers. The gap junctions of the intercellular communications occur near the cortex. The trichohyalin granule appears in the cuticular cells of completely cornified head hair. The granule is generally smaller than that of the keratohyalin granule, and spherical in shape. The granule is not visible in the area near the surface of the hair. The keratin in the cytoplasm of the cuticular cell may originate from the trichohyalin granule.

Large-scale purification of Japanese encephalitis virus from infected mouse brain for preparation of vaccine

Large volumes of Japanese encephalitis (JE) virus propagated in mouse brain can be easily purified by polyethylene glycol 6,000. By using the polyethylene glycol precipitation method, mouse hemoglobin was almost all separated from the viral suspension, and consequently the total amount of nonviral protein in the viral suspension decreased. The recovery of infectivity was about 100%. The removal of residual polyethylene glycol in the viral suspension was possible without difficulty by means of ethanol precipitation. This method is recommended as an initial step in large-scale purification of Japanese encephalitis virus propagated in mouse brain because it is simple, rapid, and inexpensive.