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Biomedical subjects

Y Hamada

Publications and source records attributed to Y Hamada.

At least 433 records · Page 24Linked to original sources
PubMed1988

Immunocytochemical study on the variation in estrogen receptors of primary and nodal metastases of breast cancer.

The variation in estrogen receptors (ER) between primary and regional nodal metastatic lesions was examined by an estrogen receptor immunocytochemical assay (ER-ICA) in 25 mammary carcinoma patients. The ER status was evaluated in terms of the percentage of ER positive stained cells, staining intensity and distribution of those stained cells. The overall ER status was consistent in both sites, however, the percentage of ER positive cells and the staining intensity were not always consistent. A decrease in the percentage of ER positive cells and staining intensity was demonstrated in the nodal metastatic lesions of 4 and 3 cases out of a total 14 ER positive cases, respectively. The mean percentage of ER positive cells in the nodal metastatic lesions was 57 per cent compared with 73 per cent in primary lesions. Thus, a tendency of both the percentage of ER positive cells and the staining intensity to decrease in nodal metastases as when compared with primary lesions in breast cancer was demonstrated.

Antibodies, Monoclonal↗
PubMed1988

Molecular cloning of cell-type-specific cDNAs exhibiting new types of developmental regulation in Dictyostelium discoideum.

By screening cDNA libraries from NC-4 cells, we have obtained five prespore-specific and two prestalk-specific cDNA clones. The two classes of prespore genes began to be expressed at the tipped aggregate stage: one class was expressed throughout development, while the other was shut off during culmination. Another class of prespore genes was expressed in vegetative cells but only in prespore cells at the later stages. Prestalk-specific genes were first expressed at the tipped aggregate stage concurrently with the two prespore gene classes, indicating the importance of this stage for transcriptional regulation in both prestalk and prespore differentiation. Except for the first prespore gene class, these represent new cell-type-specific genes as to their temporal pattern of expression.

Cloning, Molecular↗
PubMed1988

The carboxyl third of tau is tightly bound to paired helical filaments.

To obtain definitive evidence that tau is a component of paired helical filaments (PHF) in Alzheimer's disease, we fractionated and sequenced PHF-derived peptides according to a previously described procedure. In the PHF digest, we found four independent tau peptides that were located in the carboxyl third of tau. Subsequent extensive analysis of the PHF digest did not provide any other tau peptides. The conventional PHF antiserum and a new antiserum directed toward formic acid-denatured PHF reacted with the distinct CNBr fragments of tau localized on the carboxy-terminal portion of tau by protein sequencing. From these observations, we conclude that the carboxyl third of tau is tightly bound to PHF.

Aged↗
PubMed1988

Double-outlet left atrium with intact ventricular septum.

The clinical course and surgical repair of double-outlet left atrium with intact ventricular septum in a 13-year-old girl are presented. The only outlet of the right atrium was a secundum atrial septal defect, and the left atrium drained into both ventricles through two atrioventricular valves. To our knowledge, there has been only one other published report of repair of double-outlet left atrium.

Echocardiography↗
PubMed1988

Osteosarcoma. Ultrastructural and immunohistochemical studies on alkaline phosphatase-positive tumor cells constituting a variety of histologic types.

The osteosarcomas were subclassified into osteoblastic, fibroblastic, chondroblastic and telangiectatic types and examined by electron microscopy. Their immunohistochemical reactions were also studied. In an overall survey of the above types, fibroblast-like cells revealed poorly developed cytoplasmic organelles with rather short, branching rough endoplasmic reticulum, mixed with osteoblast-like cells that were hardly distinguishable from the former. They appeared to be an early stage of an osteoblastic cell lineage from the distribution and development of their cell organelles and highly positive vimentin activity. The tumor cells in malignant cartilage varied in appearance from chondroblast-like to osteoblast-like cells. All types of tumor cells expressed alkaline phosphatase activity to a significant degree. Immunohistochemical staining showed a mixture of procollagen type I-positive cells among the cells positive for both procollagen type II and S-100 protein in the malignant cartilage. Irrespective of any ultrastructural differences between these various tumor cell types, they all revealed a significant degree of ALPase activity unlike other types of bone tumors, suggesting that the tumor cells which constitute the various types of osteosarcoma are derived from a common precursor cell.

Adolescent↗
PubMed1988

[Epidermal growth factor receptor in human breast cancer].

For the purpose of demonstrating the relationship between epidermal growth factor receptor (EGFR) content in the tumor and histopathologic characteristics, 45 women with breast cancer who underwent mastectomy were analyzed. EGFR content was measured by competitive binding assay using 125I, while EGFR was detected by immunocytochemical staining. Tumors with more than 1 fmol/mg protein EGFR were defined as positive, and a good correlation between competitive binding assay and staining was observed. Seventeen of them (37.8%) had EGFR-positive tumors. Eight of the 17 EGFR-positive tumors (47.1%) were positive for estrogen receptor (ER), whereas 24 of the 28 EGFR-negative tumors (85.7%) were ER-positive. This inverse relation was statistically significant (chi 2; p less than 0.05). Twelve of the 17 EGFR-positive cases (70.6%) had axillary node involvements, against 11 of the 28 (39.3%) in the EGFR-negative cases. There was no difference in the size of primary tumor between the two groups. These results suggested that EGFR-positive tumors have more malignant potency than EGFR-negative tumors. In 8 cases, EGFR content in metastatic axillary nodes was compared with that in primary tumors. More EGFR content indicated in metastatic axillary nodes than in primary tumors without significant difference.

Antibodies, Monoclonal↗
PubMed1988

[A case of AFP-producing gastric cancer accompanied with testicular tumor].

A case of an AFP-producing gastric cancer accompanied with non-epithelial tumor is reported. A 63-year-old man, complaining of an epigastric hunger pain, was admitted to our hospital. Testing revealed that he had an extremely high level serum AFP (12,400 ng/ml) with no abnormality of liver function. A barium ingestion and a subsequent endoscopic examination determined the existence of a Borrmann III type advanced gastric cancer on the lesser curvature, extending from middle corpus to the antrum. Diagnostic imaging did not reveal any metastatic lesion in liver. After a total gastrectomy, the patient's serum AFP level rapidly decreased, followed by a recurrence he developed of a carcinomatous pleuritis and death. On autopsy, an enlargement of the right testis was noticed for the first time. Histologically, it was found to be a malignant, non-epithelial tumor, which proved negative for anti-AFP staining by the ABC method and positive for anti *L-26. On the other hand, the gastric cancer was a poorly differentiated adenocarcinoma with a hepatoid differentiation which was positive for anti-AFP staining and negative for anti-L-26 so it thus was diagnosed as an AFP-producing gastric cancer.

Adenocarcinoma↗
PubMed1988

Experimental studies on the treatment of hepatocellular carcinoma with cis-platin.transferrin complex.

Using several tumor cell lines (HC-32, C-Hc4 and MHT-1), the anti-proliferating action of cis-dichlorodiamine platinum (cis-platin) was investigated in relation to the transferrin receptors (Tf-R) expressed on the surface of these cell lines. The number of Tf-R determined by 131I-transferrin binding assay was the most in HC-32, the least in C-Hc 4 and intermediate in MHT-1. Cis-platin was found to bind stoichiometrically to transferrin and to produce more marked inhibition of 3H-thymidine uptake in the presence of apo-transferrin, suggesting that cis-platin.transferrin complex was transferred into the cells through Tf-R. Cis-platin itself increased the binding sites of transferrin. Insulin, known to cause redistribution of Tf-R to the cell surface, potentiated the inhibition of 3H-thymidine uptake induced by cis-platin and apotransferrin in the concentrations less than 50 nM. Furthermore, insulin was found to increase the binding sites of transferrin in Hc-32 in the concentrations less than 5 nM. These facts support that cis-platin was effectively transferred into the cells through Tf-R, when apotransferrin coexisted with cis-platin. Some [Ca2+]0 and protein kinase C (PK-C) modulators affected Tf-R turnover in these cell lines. These results suggested the possibility that a combination treatment of cis-platin.transferrin complex with insulin or [Ca2+]0 and/or PK-C modulators may not only enhance the antiproliferating effect of cis-platin, but also reduce the dose of cis-platin.

Binding Sites↗
PubMed1988

T lymphocyte subpopulations and immunoglobulin-containing cells in the colonic mucosa of ulcerative colitis; a morphometric and immunohistochemical study.

T lymphocyte subpopulations and immunoglobulin containing cells in the colonic mucosa of 25 patients with ulcerative colitis have been studied using an indirect immunoperoxidase technique. In ulcerative colitis a marked increase in the population of Leu 3a positive cells (helper/inducer T cells) and IgG containing cells was observed in the mucosal lamina propria. In the intraepithelial spaces, a remarkable decrease in the population of Leu 2a positive cells (suppressor/cytotoxic T cells) and a marked increase in the number of Leu 3a positive cells were revealed. There was a very significant correlation between the population of IgG containing cells and the ratio of Leu 3a positive cells to Leu 2a positive cells in the lamina propria of patients with ulcerative colitis. These results suggest that an imbalance of mucosal immunoregulatory T cells and an increased production of IgG occurred in correlation with inflammatory activities of ulcerative colitis.

Adolescent↗
PubMed1988

[Studies on the clinical significance concerning the changes in serum pepsinogen-I and gastrin levels in aged patients with chronic gastritis].

Of 86 cases of aged patients with chronic gastritis treated with Trimebutine or Flutazolam, we evaluated the changes of serum pepsinogen-I and gastrin levels in their clinical courses from the points of the correlation with severity of chronic gastritis, aging phenomenon and the changes of symptom and endoscopic findings. In order to elucidate the multidimensional interrelation among these items, we used Hayashi's quantification theory II as a conventional analysis method. In aged patients, generally, although the serum gastrin levels were rather high compared with younger generation, the serum pepsinogen-I levels were consistently low throughout their clinical courses. There were some correlation between the levels of serum gastrin and the severity of chronic gastritis. When the drugs were effective on improving the condition of the disease, the level of gastrin revealed gradual decrease. These changes of gastrin were more typical in patients treated with Trimebutine.

Aged↗