Junichi Yanagida

Expression of paraoxonase isoform did not confer protection from acute sarin poisoning in the Tokyo subway terrorist attack

Abstract We previously reported the polymorphism of the high density lipoprotein-associated enzyme paraoxonase (PON1), in the 10 sarin poisoning victims in the Tokyo subway terrorist attack. Arg192 PON1, which has low sarin hydrolysing activity, was found to be more common in the Japanese population than in people of other races. However, from our analyses seven of the victims expressed the PON1 phenotype with high sarin hydrolysing activity and three with low sarin hydrolysing activity. These results indicate that the main factor contributing to the tragedy of the Tokyo subway terrorist attack was the high toxicity of sarin rather than the race-dependent genetic difference in the Arg192 PON1 polymorphism.

Number and distribution density of ABH and MN antigen sites on young and old human erythrocyte surfaces.

There were no differences in the number of A and M antigen sites between young and old human erythrocyte surfaces. No essential differences in the number of A1, N and Vicia graminea N antigen sites could be observed between young and old erythrocytes. The number of B and H antigen sites on cell surface was significantly higher in young erythrocytes than in old ones. The distribution density of A and M antigen sites on young erythrocyte was remarkably higher than that on old ones. Compared with young erythrocytes, significant increases in the distribution density of A1, B, H, N and Vicia graminea N antigen sites were observed in aged erythrocytes. It is suggested from these and other observations that human erythrocyte aging is accompanied by elimination of a small amount of B and H antigens from cell membranes, while A, A1, M, N and Vicia graminea N antigens are not released from cell membranes during in vivo aging.

Binding of lectins to "young" and "old" human erythrocytes.

Summary“Old” human erythrocytes showed a 21.2% decrease in cell surface area and a 2% decrease in the number of WGA receptor sites, but a 27% increase in the distribution density of the WGA (lectin) receptor site, when compared with “young” human erythrocytes. For a list of lectin abbreviations, see Materials and methods). Both “young” and “old” erythrocytes exhibited very weak binding activity for 125I-labeled PNA, but there was no difference in binding activity for PNA between “young” erythrocytes and “old” ones. Compared with “young” erythrocytes, decreases in the number and distribution density of receptor sites for five lectins including LPA, Con A, RCA-II, SBA and BPA on the cell surface were observed in aged erythrocytes. “Old” erythrocytes also showed a decrease in the number of PHA-E receptor sites, while the distribution density of the same receptor site remained unchanged. In view of these and other observations, it is thought that human erythrocyte aging is accompanied by elimination of some glycoconjugates which have affinity for six lectins, LPA, Con A, RCA-II, PHA-E, SBA and BPA, whereas no WGA receptor-containing glycoconjugates are released from erythrocyte membranes. Elimination of the glycoconjugates results in shrinkage of erythrocytes to reduce their cell surface areas.

Comparative study on the main membrane-surface sialoglycopeptides released from young and old human erythrocytes with trypsin

1. The amount of sialoglycopeptide (SGP) mixture released from young (Y) erythrocytes by trypsin treatment was significantly larger than that from old (O) ones. 2. The two main membrane-surface sialoglycopeptides (Y-SGP and O-SGP) were isolated in yields of about 45% and 42% from the mixtures by a combination of Sephadex G-50 superfine gel filtration with DEAE-cellulose chromatography, respectively. Molecular weights of 12,000 and 12,100, respectively, were found for the Y-SGP and the O-SGP. 3. The Y-SGP showed a greater proportion of sialic acid than the O-SGP. The contents of galactose, N-acetylglucosamine and N-acetylgalactosamine of the Y-SGP were significantly lower than those of the O-SGP. 4. Both the SGPs exhibited the same reactivities against the MN reagents, but the reactivities against the lectins of Limulus polyphemus and Phaseolus vulgaris (E) were stronger in the Y-SGP than in the O-SGP. Neither the Y-SGP nor the O-SGP showed the reactivity to Arachis hypogaea (anti-T) lectin.

A case of homicidal choking mistaken for suicide.

This report presents an autopsy case of the homicidal choking of an adult, who died as a result of tissue paper being thrust into his mouth. An in-patient (a 29-year-old Japanese man) at a mental hospital was choked to death by another male in-patient, his roommate, who thrust a large amount of tissue paper into his mouth after rendering him slightly unconscious by cervical compression. At the time of discovery, this mental patient was believed to have committed suicide by inserting tissue paper into his own mouth. Autopsy findings and re-investigation of the case revealed that the subject had been murdered. This is a very rare case of choking used as a method of homicide.

Coronary Aneurysms in a Young Adult: Report of a Case Suspected of Kawasaki Disease

An autopsy case of coronary aneurysm was reported. The patient, a 23-year-old Japanese man, suddenly fell unconscious during a karate match and died an hour later. The autopsy revealed coronary aneurysms, one of which was accompanied by thrombosis. Histologically, the aneurysmal walls showed marked scar formation and intimal thickening and the state was regarded as healed arteritis. By taking a precise history from his parents. Kawasaki disease was thought to be the probable cause of the coronary aneurysms.

Changes in En(a-) human red blood cell membranes during in vivo ageing

The human red blood cells with phenotype En(a-) were characterized by the lack of MN antigens. The red blood cells with phenotype En(a-) which were found in a Japanese family were tested to clarify the changes in membrane surfaces of the red blood cells during in vivo ageing. The contents of sialic acid, glucose, mannose, galactose, fucose, N-acetylglucosamine and N-acetylgalactosamine of the red blood cell membranes obtained from the old red blood cells with phenotype En(a-) were significantly lower than those of the young red blood cell membranes. Neither the young nor the old red blood cells with phenotype En(a-) showed the agglutination with Arachis hypogaea (PNA) which was capable of binding to T agglutinogen. It is presumed that En(a-) red blood cells are not exposed to sialidase in vivo. In comparison with the young En(a-) red blood cell membranes, the number and the distribution density of lectin receptor sites on the old ones for Limulus polyphemus (LPA), Canavalia ensiformis (Con A), Triticum vulgaris (WGA) and Bauhinia purpurea (BPA) were significantly lower. It is thought that En(a-) red blood cell ageing is accompanied by elimination of some sialoglycoconjugates which have affinity for LPA, Con A, WGA and BPA, whereas En(a-) red blood cells lack glycophorin A.