Complete nucleotide sequences of virion RNAs from immunologically distinct vaccine strains of poliovirus (i.e., Sabin strains 1, 2, and 3) were determined by use of molecular cloning and rapid sequence analysis techniques. When the nucleotide sequences were compared, extensive sequence homology was observed among the virion RNAs in the 5' and 3' terminal regions. This result strongly suggested that the serotypes of poliovirus were derived from a putative prototype poliovirus and that the homologous sequences conserved through a long evolutionary process may have essential roles for the replication and the viral functions of the virus. Many different amino acids, predicted from the nucleotide sequences, were located in polypeptides P1-1a, especially in P1-VP1, which is located on the surface of the virion and carries viral antigens. Locations of different amino acids, together with the calculated hydrophilicity values in P1-VP1, revealed possible loci for type-specific antigenic determinants. These data on functionally important conserved sequences and on possible locations of antigenic determinants will be useful in the construction of new polio vaccine strains.

Amino Acid Sequence↗

PubMedDate not supplied

Electron microscopical studies of the effect of time lapse on outer hair cells in acoustically exposed rabbits.

After acoustic exposure of a pure tone of 2 kHz, 100 dB for 2 hours, the outer hair cells of the rabbits were observed by electron microscope. The infranuclear region of the cells in the lower half of the second turn were observed in this experiment. In this region, small vesicles, free ribosomes and coated vesicles decreased or increased in number, and the cytoplasmic matrix became lower or higher in electron density after acoustic exposure. Immediately after exposure the percentage of normal cells was 25% and increased to 60% within a period of one month. The effect of time lapse on the damaged cells' recovery is discussed.

Animals↗

PubMedDate not supplied

Individual variation and mechanism of kanamycin ototoxicity in rabbits.

In order to elucidate the mechanism of individual variation of kanamycin ototoxicity, the possible relationship between the outer hair cell damage induced by kanamycin and the levels of kanamycin in serum or perilymph and of renal damage was investigated in rabbits. No relationship was found between the extent of the outer hair cell damage and the level of kanamycin in the serum or the renal damage. The extent of the outer hair cell damage was closely correlated to the levels of kanamycin in the perilymph. These findings suggest that the individual variations in the outer hair cell damage induced by kanamycin are more closely correlated to the individual differences in the transferability of kanamycin into inner ear than to those in the vulnerability of the outer hair cells or kidneys.

Animals↗

PubMedDate not supplied

Hypochlorite scavenging activity of polyphenols.

Chemiluminescence, generated by the mixture of sodium hypochlorite solution and luminol, was completely eliminated by polyphenols, such as natural lignins, phenylpropenoid monomers and polymers, and epigallocatechin gallate. On the other hand, hypochlorite scavenging activity of polysaccharides, such as PSK (Krestin) and Schizophyllan, was relatively weak. Human myelogenous leukemic cell lines (HL-60, ML-1) showed higher production of active oxygen(s) (detected by luminol chemiluminescence) and iodination capacity, than six other cultured cell lines. Since lignin did not completely eliminate the active oxygen production by HL-60 cells, possible stimulation of hypochlorite production by lignin was suggested.

Antineoplastic Agents↗

PubMedDate not supplied

Stimulation by epigallocatechin gallate of interleukin-1 production by human peripheral blood mononuclear cells.

(-) Epigallocatechin gallate (EGCg) potently stimulated the production of interleukin-1 (IL-1) and tumor necrosis factor by human peripheral blood mononuclear cells. The intracellular amounts of IL-1 beta and especially IL-1 alpha induced by EGCg, were significantly higher than their extracellular counterparts. ECCg stimulated the production of adherent cells, with IL-1 producing capacity (per cell basis) that was significantly higher than nonadherent cells. Although IL-1 alpha mRNA synthesis (assessed by Reverse Transcriptase-Polymerase Chain Reaction) was slightly enhanced, IL-1 beta mRNA synthesis was not significantly enhanced by EGCg treatment. Lipopolysaccharide (LPS) also stimulated the production of IL-1 alpha and IL-1 beta production, but failed to induce the adherent cells. These data suggest that EGCg and LPS stimulate mononuclear cells by different mechanisms.

Antineoplastic Agents↗