Search PubMed⌕ Search

Biomedical subjects

M Tsuda

Publications and source records attributed to M Tsuda.

At least 577 records · Page 32Linked to original sources
PubMed1982

The biological activity of alpha-1-antichymotrypsin: the change of chymotrypsin-inhibitory and immunoenhancing activities by heat treatment.

The relationship between chymotrypsin-inhibitory and immunoenhancing activity of alpha-1-antichymotrypsin was studied. alpha-1-Antichymotrypsin was treated at 50 degrees C, 55 degrees C or 60 degrees C for 15 min. It was found that antichymotryptic activity was reduced by half when alpha-1-antichymotrypsin was heated at 55 degrees C and was not detected at all when heating was carried out at 60 degrees C. alpha-1-Antichymotrypsin which was heated at 60 degrees C did not form a complex with chymotrypsin, but became a substrate for chymotrypsin. The effect of native and heated alpha-1-antichymotrypsin on antibody response was studied in mice. alpha-1-Antichymotrypsin increased the number of anti-sheep erythrocytes antibody producing cells even when it was heated at 60 degrees C. Circular dichroism and single radial immunodiffusion were used to detect conformational changes. Circular dichroism in the region of side chain absorption showed that the intensities of the spectra at 296, 284, and 265 nm decreased with a rise in temperature from 50 to 60 degrees C. In single radial immunodiffusion analysis, alpha-1-antichymotrypsin did not form a halo after being heated at 60 degrees C. In conclusion, when alpha-1-antichymotrypsin was heated at 60 degrees C, the immunoenhancing activity remained intact while the antichymotryptic activity was lost with the conformational change.

Adjuvants, Immunologic↗
PubMed1982

Relationship between receptor-binding affinities and TSH-releasing activities of novel TRH analogs in the rat.

Specific bindings of 3H-TRH to rat pituitary homogenate and apparent affinities of TRH analogs for binding sites were studied. The dissociation constant for 3H-TRH binding to rat pituitary homogenate was 30 nM at 0 degrees C, and the number of the binding sites was 120 fmoles/mg protein. The apparent affinities of TRH analogs for the binding sites, which were estimated from the ability to displace 3H-TRH from those binding sites, were found to correlate well with their TSH releasing activities. These findings support the idea that the TSH releasing activities of TRH analogs depend almost entirely upon their binding abilities to the TRH receptor in the pituitary.

Animals↗
PubMed1982

Analysis of the tissue and cellular localization of alpha-1-antichymotrypsin by an immunohistochemical technique.

The cellular localization of alpha-1-antichymotrypsin (alpha 1-ACT) was studied immunohistochemically using rabbit HRP-labeled Fab' against human alpha 1-ACT. alpha 1-ACT was found in cell nuclei of carcinomas of the stomach, liver, breast, pancreas and leiomyosarcoma and in cell nuclei of lymphoid cells infiltrated into the stomach carcinoma mass. alpha 1-ACT was not found in carcinoma cells of the colon, uterus, rectum or esophagus, or in lymphoid cells infiltrated into the rectal carcinoma mass or into inflammatory regions such as gastric ulcers or appendicitis. Further, alpha 1-ACT was not found in normal cells around the carcinoma mass or in normal tissues.

Breast Neoplasms↗
PubMed1982

The role of a serum DNA-binding protein (64DP) in the diagnosis of malignant neoplasms.

A DNA-binding protein with a molecular weight of 64,000 (64DP) has been found in elevated concentrations in the serum of patients with malignant diseases. 64DP has been found to be different from any previously described tumor markers, such as AFP, CEA, and C3DP. The results obtained with column SDS - polyacrylamide gel electrophoresis are as follows. 64DP is normally present in the serum at the concentration of 48 +/- 26 micrograms/ml (n = 49). The mean value of 64DP in 96 patients with untreated malignant disease was 167 +/- 67 micrograms/ml, whereas in 41 patients with nonneoplastic disease it was 61 +/- 23 micrograms/ml. No organ or tissue specificity seems to be required for malignant neoplasms to result in elevated serum 64DP concentrations. The clinical stage of the disease does no have much effect on the levels of 64DP and, even with histologically proven early lesions, the patients showed elevated levels of serum 64DP. Following successful surgical resection, 64DP tends to fall toward the normal value. Purification of 64DP was performed and its physicochemical properties have been defined. 64DP is a glycoprotein present in the alpha1-globulin fraction and it is rich in leucine, glutamic acid, and aspartic acid in its amino acid composition. More recently, using purified 64DP preparation, a single radial immunodiffusion assay system has been developed. According to the results of this method, the diagnostic accuracy of 64DP appears to be somewhat low and even marginal for certain types of commonly encountered surgical malignancies. Studies concerning the discrepancy between the results obtained by the two assay methods are now in progress.

Carrier Proteins↗
PubMed1982

Purification, properties and identification of a serum DNA binding protein (64DP) and its microheterogeneity.

A DNA binding protein with a molecular weight of 64,000, designated 64DP, has been purified and characterized. This protein was isolated from adult human pooled serum by DEAE Sephadex column Chromatography, DNA cellulose affinity column chromatography, ammonium sulfate fractionation and Sephadex G-150 gel filtration. The final preparation of 64DP was homogeneous, as judged from polyacrylamide gel electrophoresis with or without sodium dodecyl sulfate and sedimentation experiments. Physicochemical and immunochemical properties of this protein were very similar or identical to those of alpha-1-antichymotrypsin with some differences in electric mobility and th pattern of isoelectric focusing. Furthermore, the general properties of 64DP from various sera were practically similar with the exception that isolectric focusing analysis showed microheterogeneity among 64DP purified from various sera.

Adult↗
PubMed1982

Isolation, purification and identification of a serum DNA binding protein which increases in malignant diseases.

A DNA binding protein in human serum was purified and identified. This protein was isolated from pooled human serum by DEAE Sephadex column chromatography, DNA cellulose affinity column chromatography, Sephadex G-200 gel filtration and Sepharose 6B gel filtration. It was found that the purified protein consisted of two subunits, one with a molecular weight of 80,000 and the other 25,000, evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified protein was in fact IgM determined by physicochemical and immunochemical characteristics.

Carrier Proteins↗
PubMed1982

A study of two kinds of thermoluminescent dosimeters; CaF2:Tm and CaSO4:Dy in LiF.

We studied two kinds of thermoluminescent dosimeters using 60Co gamma rays. In CaF2:Tm, the intensity of the glow curve integral as a function of dose increased linearly; the dose response curve of the main peak (at 165 degrees C) was sublinear and that of the high temperature peak (at 220 degrees C) was supralinear. In CaSO4:DY in LiF, the main peak (at 215 degrees C) and the glow curve integral as a function of dose were linear; the low temperature peak (at 170 degrees C) was sublinear. The relative responses of CaF2:Tm and CaSO4:Dy in LiF were greater than that of LiF (TLD-100) by a factor of about 11 and 4, respectively. In CaF2:Tm, the high temperature peak was very stable, but the main peak faded away with post-irradiation storage time. For CaSO4:Dy in LiF, the main peak was very stable and the low temperature peak was relatively stable. Based on the glow curve integral, we determined that the fading of CaF2:Tm and CaSO4:DY in LiF was 36 and 38%, respectively, for a month.

Calcium Fluoride↗
PubMed1981

Lipid-protein interaction in the photolysis of octopus rhodopsin.

Microvillar membranes of octopus photoreceptor cells were treated with phospholipase A2, phospholipase C, hexane, or their combinations. By these means, various membrane preparations containing qualitatively and quantitatively different lipids were obtained. The lipid composition and phospholipid content of the membrane preparations obtained by the above methods were determined. Photochemical processes in the digitonin extract of the native and treated membranes have been studied by flash photometry. The results suggest that several different variations in the lipids can affect the rates of the photochemical transformations; these are: the content of phospholipid, the amount of unsaturated hydrocarbon chains and free fatty acids.

Animals↗