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Biomedical subjects

E Okamoto

Publications and source records attributed to E Okamoto.

At least 271 records · Page 15Linked to original sources

Polymorphism of 5-methylcytosine-rich DNA in human acrocentric chromosomes.

The acrocentric chromosomes of 18 unrelated individuals were analyzed by sequential staining by the chromomycin A3/methyl green R-banding technique to identify the chromosomes, followed by an indirect immunoperoxidase technique to detect 5-methylcytosine (5MeC)-rich DNA. The short arms of both chromosomes 15 usually (92% of the chromosomes) had a large collection of 5MeC-rich DNA, which was always rich in AT base pairs. Much less commonly (11% of the possible occasions), a collection of 5MeC-rich DNA was seen on the short arm of a chromosome 13, 14, 21 or 22, and this DNA was always rich in GC base pairs. Sequential distamycin A/DAPI (DA/DAPI) and R-banding studies were carried out in 13 of these 18 individuals. There was bright DA/DAPI fluorescence of the 5MeC-rich region on the short arm of chromosome 15 but not on that of any other acrocentric chromosome. One implication of these findings is that bisatellited or other abnormal chromosomes that are DA/DAPI negative and 5MeC positive cannot be derived from number 15. In the case of a de novo chromosome of this type, the specific origin from any other acrocentric chromosome could be demonstrated by examining 5MeC-binding of the parental chromosomes.

5-Methylcytosine↗

Simple modification of Duhamel's operation for the treatment of Hirschsprung's disease. 11 year results.

Surgery was performed in 45 patients with Hirschsprung's disease utilizing our modified Duhamel's procedure. A specifically designed crushing clamp was used to eliminate the development of a blind rectal pouch and the suture line of the retained rectal end. Postoperative complications were relatively rare. Manometric study indicated that most postoperative patients had anorectal function as satisfactory as that of normal control subjects. These results suggest that our modified procedure has great advantages in terms of safety and satisfactory defecatory function for the treatment of Hirschsprung's disease.

Child↗

[Genetic studies of hydatidiform mole with 46,XY karyotype (author's transl)].

Complete hydatidiform moles are androgenetic in origin. The majority of them show a 46,XX karyotype, while some are 46,XY. Chromosome analysis of 75 complete moles revealed three (4.0%) to be so. The XY moles, the patients and their husbands were studied for various polymorphic markers, including chromosomal Q-banding heteromorphism, HLA antigen, phosphoglucomutase-1 and esterase D, in order to determine the origin of XY moles. In all of the three XY moles studied, some of the polymorphic markers were not inherited from the patients, but they were exclusively paternal. Thus, these moles were androgenetic in origin. They also showed both homozygous and heterozygous Q-banding patterns in their homozygous chromosome pairs. Therefore, they were of dispermic origin. In conclusion, XY moles are of dispermic origin.

Adult↗

Dissecting aneurysm during pregnancy and the puerperium.

According to Schnitker, Mandel, Hirst and their associates, approximately half of the dissecting aneurysms in women under 40 years of age are associated with pregnancy. This significant relationship between dissecting aneurysm and pregnancy has been discussed by considering hemodynamic stress and also the hormonal changes of pregnancy. In this report, we describe five patients with dissecting aneurysm during pregnancy or the puerperium, review the literature and discuss the influence of pregnancy on the pathogenesis of this disease.

Adult↗

[The effects of sphincteroplasty on manometric profile of common bile duct and the duodenum (author's transl)].

A simultaneous manometric monitoring of the common bile duct (CBD) and the duodenum were performed 2 weeks after choledocholithotomy on 15 patients whose common bile ducts were explored without sphincteroplasty and 30 patients with sphincteroplasty. These manometric studies were carried out by open-tip catheters intubated into the CBD and duodenum through the T-tube at the operation. In patients without sphincteroplasty, no effects of the duodenal pressure on a CBD pressure profile were recognized, while a synchronized pressure profile of the CBD and the duodenum was obtained in patients with sphincteroplasty. By stimulation with morphine (Morphine sulfate; 0.17 mg/Kg iv bolus), waxing and waning of the pressured in the CBD without sphincteroplasty were observed with 20 cmH2O in maximum at about 13 minutes after injection. However, in the CBD with sphincteroplasty, scale-over increase of the pressure curve was seen immediately after duodenal contraction caused by morphine stimulation. A direct infusion of 5 ml of 0.1 N hydrochloride to the duodenum causes hyperperistalsis of the duodenum, which made a synchronized pressure profile in the CBD with sphincteroplasty but made no remarkable change in a pressure profile of the CBD without sphincteroplasty. These findings conclude that the sphincter of Oddi plays an important role as a "pressure barrier" between the CBD and the duodenum, and that with the destruction of this sphincter by sphincteroplasty, a pressure profile of the CBD becomes close to that of the duodenum. This simultaneous manometric study of the CBD and the duodenum might be one of most valuable methods for evaluation of completeness of the sphincteroplasty.

Ampulla of Vater↗

Biochemical and histological studies on thiamine-deficient and ethanol-fed rats.

Rats were separated into four groups and four different liquid diets were given to each group. Group 1: thiamine-sufficient diet with no ethanol, group 2: thiamine-sufficient diet with ethanol, group 3: thiamine-deficient diet with no ethanol, group 4: thiamine-deficient diet with ethanol. After four weeks, all rats were fasted for 24 hr and then ethanol was given orally to every rat. After one hour, every rat was sacrificed and biochemical and histological analyses were carried out. Transketolase activity in brain and liver decreased in groups 2, 3 and 4. There was significant decrease in transketolase activity in ethanol-fed groups (groups 2 and 4) as compared to control groups (groups 1 and 3). Ethanol concentrations in blood, liver and heart of rats in groups 2 and 4 were higher than in groups 1 and 3. When comparison was made between the thiamine-deficient groups and the corresponding thiamine-sufficient groups, ethanol concentrations in liver and heart were higher in the thiamine-deficient groups. Alcohol dehydrogenase activity in liver decreased significantly in groups 2 and 4. By histological analyses, fatty degeneration was observed in the livers of groups 2 and 4. The degeneration was more prominent in group 4 than group 2. These findings suggest that chronic ethanol administration may impair the ability to metabolize ethanol and the impairment may increase when rats are in the condition of thiamine deficiency.

Alcohol Oxidoreductases↗