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T Hashida

Publications and source records attributed to T Hashida.

69 records · Page 4Linked to original sources

Neuroblastoma. Mass screening for early detection and its prognosis.

Since July 1973, the authors began developing a mass screening system using a VMA (vanilmandelic acid) spot test on 6-to-7 month-old infants for early detection of neuroblastoma in Kyoto city, Japan. Using this method, six infants with this tumor were discovered; five of the six infants were cured, and one is under treatment. These patients showed a favorable prognosis on early diagnosis. In this article, 57 neuroblastoma patients from the Department of Pediatrics, Kyoto Prefectural University of Medicine, treated during the last 20 years, from July 1962 to June 1982, are evaluated. Since the mass screening program has run smoothly since July 1974, clinical findings are compared between 35 neuroblastoma cases before mass screening from the 12-year period from July 1962 to June 1974 and 22 cases after mass screening, during the 8-year period from July 1974 to June 1982. Before mass screening, only 20% (7/35) of the patients were discovered with neuroblastoma younger than 12 months of age and 68.6% were older than 2 years of age. After mass screening, 54.6% (12/22) of the patients were younger than 12 months of age and only 31.8% (7/22) were older than 2 years of age. Before mass screening, 17.1% (6/35) survived with five of the six surviving patients being younger than 12 months of age at the time of diagnosis; 72.7% (16/22) of the patients detected after mass screening are living now. Eleven of the 16 patients have already been cured, and the remaining 5 patients are presently undergoing treatment. A marked improvement of their prognoses is dependent on the early detection of this tumor by mass screening. To date, using the VMA spot test for early detection in infancy is convenient and effective for improvement of its prognosis.

Abdominal Neoplasms↗

Bovine thymus poly(adenosine diphosphate ribose) polymerase.

About 1,300-fold purification of poly(adenosine diphosphate ribose) polymerase has been achieved from the extract of bovine thymus with a recovery of 10 to 20%. The final preparation has a purity of 99%, and the enzyme is composed of a single peptide with a molecular weight of 130,000. The purified enzyme required NAD+, Mg2+, a thiol compound, DNA, and histones for full activity. Whereas DNA is essential for activation of the enzyme, histones are not. The observed stimulation of the reaction by histones is shown to be due to masking of the inhibitory effect of contaminating denartured DNA in native DNA preparation. The concentration of DNA required for half-maximal enzyme activity (apparent Km for DNA) is proportional to the concentration of enzyme in the reaction mixture. The minimum estimation of the number of nucleotide pairs of DNA required for half-maximal activation of one enzyme molecule is 220 to 240 for bulk of calf thymus DNA, while the value is 10 for a calf thymus DNA fraction, "active DNA," which was separated from the enzyme fraction in a stage of the purification. These results suggest that the enzyme is activated by binding to a specific site on calf thymus DNA. The apparent Km for NAD+ and the maximum velocity of the enzyme are estimated to be 60 micrometer and 0.91 mumolper min per mg, respectively.

Animals↗