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Biomedical subjects

T Miyazaki

Publications and source records attributed to T Miyazaki.

At least 973 records · Page 54Linked to original sources

Continuous culture of human melanoma cells in protein-free medium: establishment and partial characterization.

Human melanoma cells (MEC) continuously grown in protein-free RPMI-1640 medium were established. These cultured cells, designated "sf-MEC," grow well in suspension and have been successfully subcultured more than 100 passages for 30 months with complete loss of serum requirement for their growth. Although sf-MEC as well as MEC had a moderate number of mature melanosomes in the cytoplasm, the tumorigenicity in nude mice was lower in sf-MEC than in MEC. In the tumor tissue formed by sf-MEC but not by MEC, a few immature melanosomes and an increased C-type-like virus production were detected. Furthermore, conditioned medium of sf-MEC stimulated DNA synthesis in both normal and transformed cells, including MEC and sf-MEC. Addition of the conditioned medium of sf-MEC in its cell growth assay caused a twofold to eighteenfold increase in cell number as compared to that for the control.

Animals↗

Radioimmunoassay of aldolase A. Determination of normal serum levels and increased serum concentration in cancer patients.

A radioimmunoassay specific for human aldolase A subunits was used to measure human aldolase A (ALD-A) in human serum. The double antibody competitive inhibition radioimmunoassay technique used radioiodinated purified ALD-A as ligand, chicken antisera specific for human ALD-A and rabbit antichicken IgG. The serum levels of ALD-A in 42 normal healthy subjects ranged from 130 to 210 ng/ml (mean average, 171 +/- 39 ng/ml). In 177 hospitalized patients without cancer, muscle diseases, or hemolytic anemia, the ALD-A serum levels ranged from 125 to 220 ng/ml. In contrast, 82% of 260 patients with various types of malignancy had ALD-A serum concentrations above the normal range. The CEA levels increased only 44% of the sera of 80 patients with cancer of the digestive tract, whereas the ALD-A levels were increased in 86% of the patients. The AFP levels were greater than 100 ng/ml in only 70% of the sera of 33 liver cell carcinoma patients, whereas the ALD-A levels were increased in 94% of these sera. The measurement of serum ALD-A by radioimmunoassay may be a valuable adjunct in the clinical diagnosis of certain cancer patients.

Adolescent↗

H NMR studies of the Fc region of human IgG1 and IgG3 immunoglobulins: assignment of histidine resonances in the CH3 domain and identification of IgG3 protein carrying G3m(st) allotypes.

A 1H NMR study of the Fc region of human IgG1 and IgG3 immunoglobulins is presented. 1H NMR data were collected for the Fc and pFc' fragments obtained from human monoclonal IgG1 and IgG3 and also from rabbit IgG. The C2-H proton signal of His-435 in the CH3 domain of IgG1 was assigned by comparing the spectra of the Fc fragment of IgG1 with that of IgG3 [G3m(g)] where there is a substitution of histidine by arginine at position 435. Chemical shifts and linewidths of the His-435 signal are quite different for the Fc and pFc' fragments. We suggest that His-435 is involved in the interdomain CH2-CH3 contact. Assignments of the C2-H proton signals of His-429 and His-433 in the CH3 domain were made on the basis of our previous 1H NMR results on the human light chain. NMR measurements clearly show that IgG3 Jir, which was isolated from a Japanese patient with cryoglobulinemia, has histidine at position 435 as in the case of IgG1. We also confirmed that IgG3 Jir reacts strongly with protein A. In marked contrast, IgG3 [G3m(g)] does not bind protein A. These results show that binding of protein A to the Fc region is not subclass-specific and the existence of His-435 is a necessary condition for the protein A binding. It has recently been demonstrated that IgG3 proteins carrying G3m(st) allotypes, which are relatively common in Mongoloid populations but quite rare in Caucasians, bind protein A strongly. We confirmed that, as expected, IgG3 Jir carries G3m(st) allotypes. The pH titration curve of His-435 observed for IgG3 Jir is quite different from that for IgG1. This result makes it possible to identify by 1H NMR IgG3 proteins carrying G3m(st) allotypes. In the case of the pFc' fragments, His-435 gives identical titration curves for IgG1 and IgG3 [G3m(st)]. This is consistent with the fact that no serological distinction can be made between the pFc' fragments obtained from these two types of proteins. We suggest that G3m(st)-specific antiserum differentiates IgG1 and IgG3 [G3m(st)] by recognizing the difference in the way in which the CH2 and CH3 domains make contact with each other.

Animals↗

Production of antibody for alpha 1-acid glycoprotein using carcinoembryonic antigen and normal fecal antigen.

The structural characteristics of carcinoembryonic antigen (CEA) and CEA-like antigen in feces and meconium were examined using antibody raised against 2 antigens. When antibody to CEA was made, anti-alpha 1-acid glycoprotein (AG) (nonprecipitating antibody) besides the precipitating antibody for CEA was made. When antibodies against each CEA-like antigen (mol. wt. 180,000) purified from feces and meconium were tested, each antibody showed a fused precipitin line for 2 antigens. Some antibodies showed the non-precipitating antibody for AG. CEA and CEA-like antigen in feces and meconium may be composed of 2 portions (AG portion and non-AG portion). Antibody specific to these antigens may be the antibody directed to the non-AG portion.

Animals↗

Mandibular traction for relieving respiratory distress in the Pierre Robin Anomaly. A case report.

A case of Pierre Robin Anomaly with severe, prolonged respiratory distress and feeding difficulties is presented. The respiratory distress is adequately relieved by mandibular forward traction. The procedure employing a mandibular suspension and elastic traction system is described. Feeding under the traction was successful, providing more effective self-control of the tongue. The authors recommend the mandibular traction device described here as a very simple life-saving approach to the problems in the Pierre Robin Anomaly.

Airway Obstruction↗

Visual training for velopharyngeal closure in cleft palate patients; a fibrescopic procedure (preliminary report).

Velopharyngeal closure in various tasks was examined in 59 cleft palate patients with persistent velopharyngeal incompetence using nasopharyngeal fibrescopic (NPF) examination. The degree of velopharyngeal closure was analyzed according to the categories reported previously by Yamaoka (1973) and Matsuya et al. (1979). The NPF self-training system was developed and applied to those patients so as to investigate a longitudinal effect of the NPF in velopharyngeal closure mechanism. The training was performed every two weeks for nearly one year. The results indicated that the patient who showed complete velopharyngeal closure during blowing and/or several productions of speech samples could attain a much better improvement in all speech samples after one year of self-training. On the other hand, the patients who did not show complete velopharyngeal closure during all tasks, failed to improve the velopharyngeal closing mechanism. The ability to close the velopharynx during swallowing was seen in all patients examined. However, it appeared to have nothing to do with the prognosis of velopharyngeal closure. The data suggested that the NPF self-training system provided a strong neuro-muscular signal for velopharyngeal movement. Besides, it was considered that the NPF was a useful tool for activation of velopharyngeal activity by way of visual feed-back control.

Adolescent↗

Inhibition of cell adhesion in Dictyostelium discoideum by tunicamycin is prevented by leupeptin.

The carbohydrate requirement for cell adhesion of aggregation-competent cells of Dictyostelium discoideum has been examined by use of a selective glycosylation inhibitor of N-glycosyl protein, tunicamycin (TM). TM completely inhibited EDTA-stable cell adhesion and glycosylation of some membrane glycoproteins in aggregation-competent cells of D. discoideum (Yamada, H., et al. (1982) J. Biochem. 92, 399-406). The present study showed that the inhibition of EDTA-stable cell adhesion by TM was prevented significantly when the cells were treated with TM in the presence of a protease inhibitor, leupeptin (LP), whereas the inhibition of glycosylation by TM was not prevented. The cell extract of aggregation-competent cells contained acid proteases, and LP strongly inhibited acid protease from D. discoideum in vitro. On analysis by SDS-polyacrylamide gel electrophoresis (PAGE), many protein bands present in the membrane fraction of control cells disappeared or decreased on TM treatment of the cells in the absence of LP, however, some of these proteins were restored when the cells were treated with TM in the presence of LP. These results strongly support an idea that EDTA-stable cell adhesion characteristic to aggregation-competent cells is mediated by glycoproteins with asparagine-linked carbohydrate. However, the requirement for the carbohydrate moiety of the glycoprotein in cell adhesion appears to be indirect in that it acts to protect the protein moiety from proteolytic degradation.

Aspartic Acid Endopeptidases↗

Protuberic acid-hydrolytic enzyme in Kobayasia nipponica and characterization of the hydrolytic products.

When the cold water-extract of Kobayasia nipponica containing a glycuronan, protuberic acid (PA), was allowed to stand at room temperature, PA was hydrolyzed. The optimum conditions for this PA-hydrolysis were 37 degrees C and pH 4-5 in 0.1 M acetate buffer. Characterization of the hydrolytic products was performed by chemical analysis, and by 1H- and 13C-NMR spectroscopy. They were identified as D-GlcUA and O-(alpha-L-IdUAp)-(1-4)-D-GlcUA. These results suggest that PA-hydrolytic enzyme(s) include at least endo-beta-D-glucuronidase.

Basidiomycota↗

Effect of intrasplenic injection of allogeneic bone marrow cells on the survival of lethally X-irradiated mice.

Radiation chimeras in mice were induced by intrasplenic injection of allogeneic bone marrow cells instead of intravenous injection. Interestingly, the survival time in X-irradiated BALB/c mice inoculated intrasplenically (i.s.) with bone marrow cells from C3H/He mice was markedly prolonged as compared with that in X-irradiated BALB/c mice inoculated i.v. with bone marrow cells from C3H/He mice. However, when C57BL/6 mice were used as donors, a significant difference between i.s. injection and i.v. injection has not been found in survival time at 60 days after X irradiation. On the contrary, when bone marrow cells from BALB/c or C57BL/6 mice were injected into X-irradiated C3H/He mice, i.s. injection gave longer survival days to recipients than did i.v. injection. Based on testing their chimerism, it was suggested that lymphoid cells of donor origin were predominantly identified in almost all BALB/c or C3H/He recipients which were inoculated i.s. with bone marrow cells from C57BL/6 mice. However, somewhat incomplete chimerism was observed when the C3H/He to BALB/c donor-recipient combination was used and vice versa.

Animals↗

Biochemical and physicochemical characterization of a mitogen obtained from an oriental crude drug, Tohki (Angelica actiloba Kitagawa).

Chemical composition and physicochemical properties of an immunomodulator, which is a non-dialyzable and acetone precipitable material(s) extracted with hot water from Angelica actiloba KITAGAWA (Yamato Tohki) (AIP), were investigated. AIP was composed of about 90% sugar and 10% protein. The major polysaccharide was identified as pectic substance(s) because its main component sugars were found to be arabinose, glucose, and galacturonic acid by gas liquid chromatographic analysis. The pectic substance(s) was not concerned with the mitogenicity of AIP since the activity was similar before and after pectinase(endo-polygalacturonase) treatment. More than half of the mitogenicity was destroyed by acid or alkali treatment. With pronase treatment, the activity was not affected, but the molecular weight of the mitogen was lowered. In addition, the mitogenic substance was partially purified from AIP by pectinase treatment and Westphal's phenol/water fractionation. The partially purified mitogenic substance(s) was rich in protein. These facts suggest that the mitogenicity of AIP was carried by a heat stable and protease resistant protein.

Amino Acids↗