Isao Ohya

Purification and characterization of pig lung carbonyl reductase

A pyrazole-sensitive carbonyl reductase from pig lung was purified to homogeneity by electrophoretic criteria. Chemical cross-linking study suggested that the native enzyme is a tetramer with a Mr of 103,000, consisting of apparent identical subunits of Mr 24,000. The enzyme reduced aliphatic and aromatic carbonyl compounds with NADPH as a preferable cofactor to NADH and catalyzed the oxidation of secondary alcohols and the aldehyde dismutation in the presence of NAD(P)+. Immunohistochemical study with the antibodies against the enzyme revealed that the enzyme was localized in the ciliated cells, nonciliated bronchiolar cells, Type II alveolar pneumocytes, and the epithelial cells of the ducts of the bronchial glands in the pig lung. In addition to the properties and distribution, the pig lung enzyme was immunochemically similar to the pulmonary enzymes in the guinea pig and mouse. However, the pig enzyme showed the following unusual features. (1) The enzyme exhibited an equatorial specificity in the reduction of 3-ketosteroids; the 4-pro-S hydrogen of NADPH was transferred to the carbonyl carbon atom of 5 alpha- and 5 beta-androstanes, and the respective reduced products were identified as 3 beta- and 3 alpha-hydroxysteroids. (2) Although the NADPH-linked reduction of carbonyl compounds apparently obeyed the Michaelis-Menten kinetics at pH 6.0, the double-reciprocal plots of the velocity vs concentrations of the carbonyl substrates were convex at pH higher than 6.5. The Hill coefficients and [S]0.5 values for the substrates decreased as the pH for reaction increased. The results suggest that the pig enzyme exhibits negative cooperativity with respect to the carbonyl substrates and that the hydrogen ion acts as an allosteric effector abolishing the negative interaction.

Analysis of the STR loci HUMF13A01, HUMFXIIIB, HUMLIPOL, HUMTH01, HUMTPOX and HUMVWFA31 in a Japanese population

Population studies on six short tandem repeat loci, HUMF13A01, HUMFXIIIB, HUMLIPOL, HUMTH01, HUMTPOX and HUMVWFA31 were carried out in a sample of unrelated Japanese individuals (n = 337–545) living in Gifu Prefecture (central region of Japan). Five alleles could be identified for HUMFXIIIB, six for HUMF13A01, HUMLIPOL, HUMTH01 and HUMTPOX, and eight for HUMVWFA31. For all/six loci no deviations from the Hardy-Weinberg equilibrium hypothesis were detected. The mean exclusion chance ranged from 0.22 to 0.60, the power of discrimination from 0.63 to 0.93, and the expected heterozygosity from 0.43 to 0.80. Allele frequency distributions for the loci in the Japanese sample were not similar to those in samples from other racial or ethnic groups except for the Chinese (for HUMTPOX). The results demonstrate that HUMTH01, HUMTPOX and HUMVWFA31 are more useful for forensic investigations in the Japanese population than the other three loci.

Localization of Pulmonary Carbonyl Reductase in Guinea Pig and Mouse: Enzyme Histochemical and Immunohistochemical Studies'

We studied the localization of carbonyl reductase (E.C. 1.1.1.184) in guinea pig and mouse lung by enzyme histochemistry and immunohistochemistry, using antibodies against the guinea pig lung enzyme which crossreacted with the lung enzymes of both animals. Carbonyl reductase activity was detectable in the bronchiolar epithelial cells of small airways and in alveolar cells. In the immunohistochemical staining for carbonyl reductase, the reaction was strongest in the non-ciliated bronchiolar cells (Clara cells) and was weak in the ciliated cells and type II alveolar pneumocytes. Injection of a single dose of naphthalene led to significant impairment of carbonyl reductase activity and of microsomal mixed-function oxidase activities in mouse lung, with a marked decrease in both activity and immunoreactive staining in the bronchiolar epithelial cells. The results indicate that carbonyl reductase is localized primarily in the Clara cells, which are known to be sites of pulmonary drug metabolism.

Fetal death from abruptio placentae associated with incorrect use of a seatbelt

A female driver, 24 weeks pregnant, was wearing a three-point seatbelt in the manner usual for nonpregnant women, when her automobile collided head-on with another vehicle. A cardiotocographic examination after the accident revealed the fetus to be alive. Five days after the accident, however, a cardiotocographic examination showed fetal death. At that time, a transverse ecchymotic band on the lower abdominal wall that had not been observed at the first examination was noticed. Eight days after the accident, the mother delivered a macerated female fetus. At autopsy, the baby showed no abnormality, but there was a hematoma on the placental surface toward the uterus. These results suggest that the fetus died of abruptio placentae associated with incorrect placement of the lap belt.

Anomalous origin of the right coronary artery from the left sinus of Valsalva: report of two cases

Anomalous origin of the right coronary artery (RCA) from the left sinus of Valsalva (LSV) is rare and has only recently been recognized as a cause of sudden cardiac death in otherwise healthy individuals. In this report, we describe two cases of anomalous origin of the RCA from the LSV. In the first case, a previously healthy 11-year-old girl died suddenly and unexpectedly. An autopsy revealed no abnormalities, except for anomalous origin of the RCA from the LSV. In the second case, a 21-year-old woman died by drowning in a bath, probably after an episode of syncope brought about by anomalous origin of the RCA from the LSV.

Analysis of the VNTR locus D1S80 in a Japanese population

SummaryA population study on the VNTR locus D1S80 was carried out in a sample of 377 unrelated Japanese individuals living in and around Gifu Prefecture (central region of Japan). A total of 29 different alleles was distinguished. Alleles 18, 24 and 30 were found to be the 3 most common alleles in this population sample and their frequencies were 0.147, 0.200 and 0.162, respectively. Out of the 435 possible phenotypes, 120 were observed. The observed heterozygosity was 0.88 and the power of discrimination was 0.98. No significant deviations from Hardy-Weinberg equilibrium could be found in this Japanese population sample.ZusammenfassungEine populationsgenetische Studie über den VNTR Locus D1S80 wurde an einer Stichprobe von 377 unverwandten Japanern durchgeführt, welche innerhalb und in der Umgebung der Gifu-Präfektur (ZentralJapan) leben. Insgesamt wurden 29 verschiedene Allele unterschieden. Die Allele 18, 24 und 30 waren die 3 häufigsten Allele in dieser Populationsstichprobe, und ihre Frequenzen waren 0,147, 0,200 und 0,162. Von insgesamt 435 möglichen Phänotypen wurden 120 beobachtet. Die beobachtete Heterozygotie-Rate war 0,88 und der Diskriminations-Index betrug 0,98. In der untersuchten japanischen Stichprobe wurden keine signifikanten Abweichungen vom Hardy-Weinberg-Gleichgewicht gefunden. lated Japanse individuals living in and around Gifu Prefecture (central region of Japan).

Sudden death due to undiagnosed intracranial hemangiopericytoma.

A previously healthy 9-year-old Japanese boy with a 4-day history of vomiting and headache died suddenly and unexpectedly. An external examination revealed no abnormalities other than foam around the mouth and nose. An internal examination revealed severe pulmonary edema and hemorrhagic hemangiopericytoma arising from the choroid plexus of the right lateral ventricle. The cause of death was thought to be neurogenic pulmonary edema caused by the rapid growth of a hemangiopericytoma, with intratumoral hemorrhage.

An application of a quantitative analytical system for the grading of pulmonary fat embolisms

The severity of pulmonary fat embolism in 5 autopsied cases has been measured using a quantitative image analytical system. With reference to the mean size of the fat emboli, the cases were divided into 2 groupings regardless of the number of the emboli. The mean sizes of the emboli in 3 cases of the first group were significantly larger (about 490-600 microns 2) than those found in the 2 cases of the other group (about 220 and 235 microns 2). An investigation into the localization of fat emboli revealed that more were lodging in the small arteries and arterioles in the first group than in the second. Our results have indicated that a reliable grading of pulmonary fat embolism can not be established without a quantitative image analysis of the size and localization of the fat emboli, and that this quantitative analytical method is useful in achieving this reliable grading.

Japanese Population DNA Typing Data for the Loci LDLR, GYPA, HBGG, D7S8, and GC

Population studies on the five loci LDLR, GYPA, HBGG, D7S8, and GC (PM loci) were carried out in a sample of 366 unrelated Japanese individuals living in Gifu Prefecture (central region of Japan) using the AmpliType PM PCR Amplification and Typing kit (Perkin Elmer). For all loci, no significant deviations from Hardy-Weinberg equilibrium could be found in our Japanese population sample. The combined mean exclusion chance and power of discrimination for the PM loci were 0.68 and 0.993, respectively. The Japanese and Chinese population data were similar for the all loci. The Japanese and Korean population data were similar for all loci other than D7S8. Significant differences were observed between the Japanese population data and the 16 other population data compared for 3 loci or more.

Ultrastructual Localization of Carbonyl Reductase in Mouse Lung.

SummaryThe immunocytochemical localization of tetrameric carbonyl reductase in the mouse lung was determined by an electron-microscopical immunogold procedure using monospecific antibodies against the enzyme. The labelling of carbonyl reductase was observed within the mitochondria of the ciliated and non-ciliated cells of the bronchioles and the type II alveolar pneumocytes, and the density of labelling in the non-ciliated cells was higher than those in the other cells. No significant labelling was detected over other compartments of the epithelial cells. The labelling was undetectable in the type I alveolar cells, alveolar macrophages and connective tissue cells of the lung. These results clearly indicate the localization of carbonyl reductase to the mitochondrial matrix of these epithelial cells, of which the non-ciliated bronchiolar cells contained particularly high amounts of the enzyme.