Search PubMed⌕ Search

Biomedical subjects

K Minakata

Publications and source records attributed to K Minakata.

58 records · Page 4Linked to original sources

Denatured hemoglobin in sickle erythrocytes.

To study the nature of numerous inclusion bodies seen in red cells from patients with sickle cell disease (Hb SS), we have prepared red cell ghosts free of oxyhemoglobin and analyzed them by spectrophotometric and heme extraction methods. The absorption spectrum in the visible region of the ghost suspensions was typical of hemichromes. The spectrum was similar to that of denatured hemoglobin repared by treatment of oxyhemoglobin S with mechanical shaking or heat. Similar treatment of cells containing only normal hemoglobin (Hb AA) showed a very small amount of denatured hemoglobin, approximately one-fifth of the amount in Hb SS cells. The amount of denatured hemoglobin determined after solution of membrane with 2.5% sodium dodecyl sulfate was 0.158+/-0.070% (1 SD) of the total cellular heme in Hb SS patients. In controls, the amount was 0.030+/-0.016%. Persons with Hb AA and reticulocytosis did not have an elevated amount of membrane-associated heme. In patients with hereditary spherocytosis and autoimmune hemolytic anemia, denatured stromal hemoglobin was normal or slightly elevated before and after splenectomy. The increased amount of denatured hemoglobin in Hb SS red cells may be related to the instability of sickle oxyhemoglobin.

Adolescent↗

[Trypsin inhibitors in human urine (author's transl)].

By using ammonium sulfate, Arg-Sepharose and gel filtration, an urinary trypsin inhibitor (UTI) with molecular weight of 67,000 (UTI7) was isolated from normal human urine. The yield of UTI7 was about 3,200 U per liter of urine. When urine was acidified, an uropepsin-like substance was activated which caused molecular weight change of UTI7. New UTIs had molecular weight of 45,000 and 22,000 (UTI4-5 and UTI-2-2), respectively. These inhibitors showed a strong effect on trypsin, alpha--chymotrypsin and lesser extent on plasmin and elastase, but had no effect on esterolytic activity on thrombin and the first components of complement Cls an Clr.

Electrophoresis, Polyacrylamide Gel↗

A computer calculation of probability of monozygosity for twins.

A general algorithm is described to calculate the probability of monozygosity of concordant twins on the basis of blood type tests. Frequencies of all combinations of twins and parents are created with the aid of a translational matrix which facilitates conversion of genotypes to phenotypes automatically. The method of calculation is explained by taking Rh system in Germany as an example. The probability of monozygosity is calculated for all combinations of twin and/or father and/or mother. Effects of parental phenotypes on the efficiency in the diagnosis are analyzed quantitatively. Applicability of this method to other calculations concerning genetics is also discussed.

Blood Group Antigens↗

Surgical repair for supravalvular aortic stenosis: intermediate to long-term follow-up.

BACKGROUND AND AIM OF THE STUDY: Supravalvular aortic stenosis (SAS) has been surgically treated by either single-sinus or bisinus patch repair. This article reviews intermediate to long-term results of repair in patients with SAS at our institute. METHODS: Between 1974 and 1995, eight patients underwent surgical repair for SAS. The age range was 1.3 to 14 years (mean 7.3 years). The morphology was the discrete type in seven patients and the diffuse type in one patient. The pressure gradient across the obstruction was 20 to 105 mmHg (mean 68 mmHg). Two patients in the early period of the series underwent single-sinus patch repair, and six underwent bisinus patch repair (pantaloon-shaped patch, extended aortoplasty). RESULTS: There were no operative deaths, and the mean pressure gradient was reduced to 23 mmHg (p < 0.001) in the early postoperative period. The median follow-up period was 8.0 years (1.8-17.3 years). One patient with diffuse type SAS required reoperation 12.8 years later due to progression of the stenosis, and died after the operation. The remaining seven patients were alive and well at the last follow-up, when the pressure gradient ranged from 6 to 31 mmHg (reoperation excluded). CONCLUSION: Surgical repair for discrete type SAS provides satisfactory results in the intermediate to long-term follow-up.

Adolescent↗