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I Kunugiyama

Publications and source records attributed to I Kunugiyama.

4 recordsLinked to original sources

Measurement of erythrocyte volumes in splenectomized horses and sham-operated horses at rest and during maximal exercise.

Erythrocyte volumes of thoroughbred horses were measured. The volumes of splenectomized horses and sham-operated horses 2 hr after injection of 50Cr-tagged erythrocytes (at rest) and during maximal exercise were measured using the non-radioactive isotope 50Cr. Because splenic erythrocytes are released into circulation during exercise, it was estimated that the erythrocyte volumes of the sham-operated horses during maximal exercise are larger than those of the horses at rest. However, the erythrocyte volumes of the sham-operated horses at rest were about equal to those during maximal exercise. In the splenectomized horses, furthermore, erythrocyte volumes at rest and those at exercise were nearly equal. From these results, blood stored in the equine spleen is gradually mixed with circulating blood, and it was clarified that the phenomenon was completed within 2 hr. Although it is basically impossible to measure the circulating erythrocyte volume at rest using the erythrocyte tagged method, we observed that it is possible to measure the total erythrocyte volume using the 50Cr method. Also, the plasma volumes of the splenectomized horses during maximal exercise were found to be slightly smaller than those at rest. On the other hand, in the sham-operated horses, the plasma was decreased by a large quantity after maximal exercise. Therefore, it was suggested that the spleen participates in the phenomenon involving the disappearance of plasma from circulation due to exercise.

Animals↗

Measurement of beta 2-microglobulin in bovine serum and urine by radioimmunoassay.

A radioimmunoassay (RIA) system for quantification of bovine beta 2-microglobulin (beta 2-M) in serum and urine was developed. The protein isolated from bovine colostrum showed a single band in SDS-PAGE, and its molecular weight was approximately 11,600. Amino acid sequences for the first 24 residues and the amino acid composition of the protein were in agreement with those in the bovine beta 2-M of previous research works. In an Ouchterlony test, a single precipitation line was formed between the protein and the antiserum made by the protein. From these results, it was confirmed that the protein isolated from the colostrum was pure bovine beta 2-M. For creation of an RIA calibration curve for urine, a urine void of beta 2-M, as much as possible (beta 2-M-free urine), and a PBS were used as diluents. Intraassay (n = 10) and interassay (n = 3) variances were 1.7-4.6% and 7.1-11.5% in the PBS dilute method, and were 1.4-5.1% and 12.3-13.5% in the beta 2-M-free urine dilute method, respectively. Mean recoveries were 160 +/- 19% (mean +/- SD) and 98.4 +/- 7.9% in PBS and beta-M-free urine, respectively. It was found that the method using the beta 2-M-free urine as a diluent was more accurate than using PBS. The beta 2-M concentrations in serum and urine of healthy Holstein cows measured by this RIA system showed a logarithmic normal distribution for urine and a normal distribution for serum. The mean beta 2-M concentrations were 0.0305(+0.04443)(-0.0210) mg/l (Geometric mean +/- S.D., n = 43) in urine and 2.87 +/- 0.45 mg/l (Arithmetic mean +/- S.D., n = 26) in sera. Further, we could not observe the particular tendency of daily variation in urinary beta 2-M concentrations of healthy cows (Holstein, n = 3 x 2 days).

Amino Acid Sequence↗

Decrease in erythrocyte survival in Theileria sergenti-infected calves determined by non-radioactive chromium labelling method.

Pathogenesis of anemia in the calves infected with Theileria sergenti was investigated from the viewpoint of erythrocyte survival decrease in the circulating blood. For investigation of erythrocyte survival a method of erythrocyte labelling with non-radioactive chromium (50Cr) was utilized. It was found that (1) the erythrocyte survival decreased markedly in the T. sergenti-infected calves compared with that in the uninfected calves; the survival rate of 25.7% for infected calves and 86.0% for uninfected ones on the fourth day after re-introduction of the labelled erythrocytes into the original donors, and that (2) the survival of non-parasitized erythrocytes in the infected calves was also decreased, which indicates no obvious relationship between parasitism and decrease in survival of erythrocytes.

Anemia↗

Determination of blood volume in dogs using an enriched stable isotope 50Cr.

For the measurement of canine blood volume, various experimental conditions and techniques have been investigated using a non radioactive stable isotope 50Cr. On the basis of the results in this preliminary work, erythrocytes were labeled using 50Cr. Five micrograms of 50Cr per 1 ml of blood was added and incubated for 60 min. The canine erythrocytes were tagged using 50Cr and injected into vein of the same dogs. The blood samples collected at 60 min after the injection were irradiated by thermal neutron for 20 min at the reactor of the JAERI. Activities of 51Cr (the 50Cr concentration method) and 51Cr/59Fe radioactivity ratios (the 51Cr/59Fe ratio method) in the samples were measured. There was a very high correlation (r = 0.97, P less than 0.001) between the blood volumes calculated by the 50Cr concentration method and the 51Cr/59Fe ratio method. The latter method is less complicated than the former, because measurement of the sample weight and correction of thermal neutron flux are unnecessary. The mean blood volumes calculated by the ratio method and the Evans blue method were 89.8 +/- 6.8 ml/kg B.W. (mean +/- SD) and 98.9 +/- 10.6 ml/kg, respectively, showing a significant difference between them (P less than 0.05). However, these values are almost in accord by correction of venous blood PCV values with factor 0.97. As a detection limit of 50Cr was approximately 0.1 ng per 1 ml of blood in this system, this method has been concluded to be applicable to the measurement of the blood volume of cattle.

Animals↗