Molecular epidemiology of adenovirus type 8 (Ad 8) in Taiwan: four subtypes recovered during the period of 1980-1981 from patients with epidemic keratoconjunctivitis

Adenovirus type 8 (Ad 8) has been the major and important causative agent of epidemic keratoconjunctivitis (EKC). By enzymatic cleavage analysis with five endonucleases, PstI, HindIII, BamHI, SalI and SstI, 27 out of 149 Ad 8 isolates recovered from patients with EKC during the period from July, 1980 to July, 1981 in Kaohsiung, Taiwan, were studied. By cleavage patterns, 27 Ad 8 isolates in Kaohsiung were classified into four subtypes which were found to be different from the subtypes (Ad 8A, Ad 8B) prevalent in Sapporo (1).     

Purification and characterization of a bovine colostrum low molecular weight cysteine proteinase inhibitor

Large amounts of cysteine proteinase inhibitors were found in bovine colostrum. One had a molecular weight of 90,000, and the other a molecular weight of 10,500. The concentrations of both these inhibitors were highest the day after parturition, and were about one-tenth as much on day 7. The lower molecular weight inhibitor was purified by acid treatment, ammonium sulfate fractionation, gel filtration on Sephadex G-50, CM-Sephadex chromatography and rechromatography on Sephadex G-50. The purified preparation gave a single band on SDS-polyacrylamide gel electrophoresis. This inhibitor contained one tryptophanyl residue and one cystinyl residue, and did not contain a free thiol group. Values obtained for its isoelectric point (pI) were 10.0 and 10.3. This material strongly inhibited cathepsin B, cathepsin H, and papain. the higher molecular weight inhibitor was partially purified. It had a pI of 4.2 and inhibited papain, cathepsin H, and cathepsin B.     

Effect of high carbohydrate diet on serum gamma-glutamyl transpeptidase fraction pattern in Japanese young men

Changes in the activity of serum gamma-glutamyl transpeptidase (gamma-GTP) and the percentage of the gamma-GTP fraction in healthy young men given a high carbohydrate diet (480-636 g/day, 80% of the total energy) for 21 days were examined. Serum total gamma-GTP activity showed no significant change in four healthy young volunteers who received high carbohydrate diet for 21 days. However, the percentage of the gamma-GTP (1) fraction increased significantly (P less than 0.01) from the basal level of 55.6 +/- 4.0% to 67.6 +/- 0.9% on day 10, and then decreased to 58.4 +/- 1.4% on day 21. When the experimental diet was replaced by usual diet, the percentage of the gamma-GTP (1) fraction returned to the same level as before the experiment. It is concluded from the results that the nutrient intake affects the percentage of gamma-GTP (1), but not the total serum gamma-GTP activity.     

Vasorelaxing actions of molsidomine and its metabolites, in comparison with nitroglycerin

The effect of a novel antianginal agent, molsidomine (N-ethoxycarbonyl-3-morpholinosydnonimine) (SIN-10) and its metabolites, 3-morpholinosydnonimine (SIN-1) and N-nitroso-N-morpholinoaminoacetonitrile (SIN-1A) on isolated dog blood vessels were investigated. SIN-1 and SIN-1A elicited a concentration-dependent relaxation of prostaglandin F2 alpha, contracted strips, while SIN-10 was without effect even in a concentration of 10(-4) M. The mean effective concentration (EC50) values of SIN-1A were much lower than SIN-1 and other vasodilators including nitroglycerin. The time course of relaxation was more rapid and transient in response to SIN-1A than to SIN-1. Adrenergic and cholinergic blocking agents did not affect the relaxing responses to SIN-1 and SIN-1A. SIN-1A also attenuated the norepinephrine-, KCl-, Ca2+-, or electrical transmural stimulation-induced contractile response, but SIN-1A increased the [3H]norepinephrine release from the adrenergic nerve terminals in response to transmural stimulation. Methemoglobin, which reportedly binds nitric oxide, or methylene blue, an inhibitor of guanylate cyclase, attenuated the relaxing response to SIN-1A. These results indicate that the vasodilating action of molsidomine results from the direct action on the vascular smooth muscle and suggest that the action is caused by its metabolites, probably SIN-1A, which contains a nitric oxide-moiety in the molecule. The possible mechanism of vasorelaxing action of SIN-1A is discussed in comparison with that of nitroglycerin.     

Effect of TPA on the mutagenicity of caffeine in the soybean mutation test

12-O-Tetradecanoylphorbol-13-acetate (TPA) is a well-known tumor promoter in mouse-skin carcinogenesis. Its effects on mutagenesis in a soybean test system were examined, and the effects were judged from the appearance of spots of various colors on the leaves. When soybean seeds were treated with TPA plus 0.03% caffeine, the frequency of spots per leaf decreased significantly and in proportion to the concentration of TPA. TPA alone at concentrations of 1–20 μg/ml did not induce any mutations. Mutations induced by γ-rays were not affected by administration of TPA either before or after exposure to γ-rays. The mechanism of suppression by TPA of mutations induced by caffeine is discussed.     

Inter- and intramolecular stacking interaction between indole and adeninium rings

Crystals of 1,9-dimethyladeninium-indole-3-acetate (1:1) complex (I) and 9-(3-indol-3-ylpropyl)-1-methyladeninium iodide (II), an inter- or intramolecular model for the stacking interaction between the tryptophanyl residue and the methylated (or protonated) adenine base, were subjected to X-ray analyses. Nearly parallel stacking and interplanar spacing near to 3.4 A were observed between the indole and adeninium rings of both crystals. In particular, one of the two stacking pairs formed in I showed the existence of a partial charge-transfer interaction in their ground states. On the basis of the molecular orbital consideration, the mutual orientation between these stacked aromatic rings is considerably governed by the orbital interaction between the highest occupied molecular orbital of the indole ring and the lowest unoccupied one of the adeninium ring. The ring stacking observed in II was stabilized by the strong coupled dipole-dipole interaction. Absorption, fluorescence, and proton nuclear magnetic resonance spectra indicated the existence of a stacking interaction in the aqueous solutions of I and II, as well as in their crystalline states. The biological implication for the observed stacking interactions has been discussed.