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Biomedical subjects

T Okishima

Publications and source records attributed to T Okishima.

8 recordsLinked to original sources
PubMed1992

Cardiovascular anomalies in chick embryos produced by bis-diamine in dimethylsulfoxide.

N,N'-bis(dichloroacetyl)-1,8-octamethylenediamine(bis-diamin e) (100 micrograms) dissolved in dimethylsulfoxide (DMSO) was administered to early developing chick embryos (Hamburger-Hamilton stage 9-21) in order to clarify the teratogenic effects on the cardiovascular system and to determine whether bis-diamine interferes with the migration of neural crest cells. Of 346 cases, 154 (44.5%) survived. The incidence of cardiovascular anomalies was 149 out of 154 cases (96.8%). Infundibular ventricular septal defect, double outlet right ventricle, and persistent truncus arteriosus were the primary cardiac anomalies observed in this study. A high percentage of these anomalies were accompanied by hypoplasia of the right 6th aortic arch artery and persistent left 4th aortic arch artery. Particularly, administration of bis-diamine to chick embryos at stage 13 resulted in a high incidence of persistent truncus arteriosus (64.3%). Bis-diamine has been suspected to inhibiting the migration of neural crest cells. However, neural crest cells were observed in the tunica media of the great arteries and the truncal valves of persistent truncus arteriosus produced by bis-diamine in chimeric embryos at stage 13. Morphological changes such as cell death were not observed.

Abnormalities, Drug-Induced↗
PubMed1990

Association of cephalic neural crest cells with cardiovascular development, particularly that of the semilunar valves.

The quail-chick chimera method was used to examine whether neural crest cells were associated with the formation of semilunar valves. From the metencephalon to somite 5, or from the otocyst to somite 3, left, right, or bilateral neural folds, including the neural crest, were transplanted. Among embryos used for the experiment, three into which left neural crest cells were transplanted, two into which right neural crest cells were transplanted, and two into which bilateral neural crest cells were transplanted had a morphologically normal heart. In these embryos, neural crest cells were found in all cusps of the aortic and pulmonary semilunar valves. Although neural crest cells have been thought to have no association with the formation of the semilunar valves, our experiment indicates that such association indeed occurs.

Animals↗
PubMed1990

Truncus solitarius pulmonalis.

The case of a female neonate with truncus solitarius pulmonalis (TSP), a rare congenital heart anomaly, is reported. She died four days after birth. A single right ventricle with common atrioventricular (AV) valve was associated with (Collet & Edwards type II) truncus arteriosus communis, and appeared to have a single coronary artery with an abnormally high take-off near the origin of the right subclavian artery. However, the vessel that appeared to be the single coronary artery was in fact an extremely hypoplastic ascending aorta associated with aortic atresia and agenesis of the left ventricle and mitral valve.

Coronary Vessel Anomalies↗
PubMed1990

Teratogenic effects of sodium valproate in the Jcl: ICR mouse fetus.

Sodium valproate was administered to Jcl:ICR mice in order to evaluate its teratogenicity. A single dose of 600 mg/kg of sodium valproate was injected intraperitoneally on gestational day 6, 7, 8 or 9. On day 18 of gestation, dams were laparotomized, and live fetuses were inspected for the presence of external and internal abnormalities. Exencephaly and urogenital abnormalities showed the highest frequency in the group treated on day 8, being recognized in about 60% and 10% of live fetuses, respectively. Cardiovascular abnormalities were found in the highest frequency in the group treated on day 7 (in about 30% of live fetuses). Incidence of tail abnormality was found to increase with delay in day of drug administration. Other abnormalities observed were cleft palate and digital malformation. Our study showed that a constellation of major abnormalities similar to the congenital valproate syndrome suspected in humans could be produced in the Jcl:ICR mouse fetus.

Abnormalities, Drug-Induced↗
PubMed1989

Association of congenital heart disease, blepharoptosis, and short stature.

We found 12 patients with congenital heart disease of unknown etiology complicated with blepharoptosis during a period from Sept. 1, 1981 to April 30, 1989. All the patients with congenital heart disease were acyanotic, including 10 with short stature. Among these 10, abnormalities of high frequency were intrauterine growth retardation (5 cases), mental retardation (5), microcephaly (3), epicanthus (4), high arched palate (4), sacral dimple (4), and distal axial triradius (3). It is postulated that the association of congenital heart disease, blepharoptosis and short stature might indicate pathogenetic relationships.

Blepharoptosis↗
PubMed1988

An infant with suspected right ventricular dysplasia presenting unique ventriculograms.

Angiocardiography was performed twice in a male infant at ten days after birth due to cyanosis during crying and at 4 years and 10 months of age for close examination of the heart prior to an operation for cerebral abscess. Outpouchings resembling multiple diverticula were observed in both ventricles, though more notably in the right ventricle, as well as slight enlargement and reduced ejection fraction of both ventricles. Evaluation of oxygen saturation indicated right-to-left shunt at the atrial level. Electrocardiography suggested a marked superior axis deviation, and chest roentgenography and two-dimensional echocardiography revealed enlargement of the right atrium and right ventricle. Soon after the examinations, the patient died suddenly during sleep at home. Since autopsy was not performed, a definitive diagnosis could not be made, but right ventricular dysplasia appeared likely. The unique angiocardiographic findings and clinical course of this rare patient are described.

Angiocardiography↗
PubMed1985

Unique types of criss-cross heart.

Three cases of criss-cross heart which we have observed during last five years are described. All of these cases were diagnosed by angiocardiography and two-dimensional echocardiography, and one of them was verified by autopsy. Two of them are unique among cases reported thus far. Case 1 shows ordinary criss-crossing with supero-inferior ventricle, and case 2, extreme crossing atrioventricular (A-V) valves, in which the right-sided right atrium connects to the left posteriorly positioned right ventricle through the tricuspid valve, and the left-sided left atrium to the right anterior left ventricle via a posteriorly positioned mitral valve. In case 3, the criss-cross appearance is secondary to displacement of the heart by compression caused by a diaphragmatic hernia. Findings in these cases suggest that criss-cross heart is caused not only by primary rotation of the ventricles during cardiac morphogenesis but also by secondary rotation of a formed heart induced by extracardiac compression. The degree of rotation in these cases revealed a wide spectrum from minimal to extreme. In addition, subxiphoid two-dimensional contrast echocardiography is recommended as the only accurate method of non-invasive diagnosis of this condition.

Angiocardiography↗