We have studied the resolution of DL-amino acids on a native cellulose column. All the DL-amino acids related to protein and their 16 DNP-DL-amino acids were separated. The resolution capability depends mainly upon the bulkiness of the side group attached to the alpha-carbon, but also on structural and functional interaction of amino acid with cellulose. We propose a plausible resolution mechanism that is thought to be governed by a so-called key and lock relation between an amino acid and cellulose. Then, the affinity of each enantiomer for cellulose was calculated based on the resolution factor, which was known to be some 10(-2) -10(-3) eV.

Amino Acids↗

PubMedDate not supplied

Magnetic resonance imaging of patients with intention tremor.

We evaluated the magnetic resonance images of the patients with intention tremor. Five patients out of seven had some atrophic structures or changes in signal intensity in the cerebello-rubral thalamic tract. Moreover, the T2-weighted images of the patients group detected the dentate and red nuclei more poorly than those of our control group. From these results, the etiological significance of the tract was confirmed and the mechanism of the intention tremor onset was discussed.

Adolescent↗

PubMedDate not supplied

Reduction in the incidence of Helicobacter pylori-associated carcinoma in Japanese young adults.

Helicobacter pylori (Hp) is a major risk factor for gastric carcinogenesis. In Japan, the incidence of Hp infection in young adults has declined markedly. The purpose of this study was to clarify this trend in the incidence of Hp-associated gastric carcinoma (GCa) in young (under 30 years of age) Japanese patients. We enrolled 53 such patients who underwent surgical resection of GCa in one of 18 hospitals in the Hiroshima prefecture between 1976 and 1999. The patients were classified into groups based on three 8-year periods (1976-83, 1984-91, and 1992-1999) in which their cases occurred. We compared the numbers of patients and estimated the histology of carcinomas, grades of gastritis and Hp infection histologically. Of the 53 patients, 49 (92%) showed Hp infection. The frequency of GCa in young adults has decreased gradually (21, 18, and 14 patients in 1976-83, 1984-91 and 1992-99, respectively). The numbers of Hp-positive carcinomas decreased radically (21, 17 and 11 patients, respectively). This trend was associated with improvement in the degree of gastritis in non-neoplastic mucosa. Of the four Hp-negative patients, three had signet ring cell carcinoma. Moreover, the numbers of patients with non-signet ring cell carcinoma also decreased (18, 12 and 7 patients in each period, respectively). These results suggest that Hp-associated carcinoma has declined gradually in young Japanese.

Adolescent↗