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Biomedical subjects

M Terada

Publications and source records attributed to M Terada.

At least 469 records · Page 26Linked to original sources
PubMed1988

Purification, crystallization, and characterization of peroxidase from Coprinus cinereus.

Peroxidase (donor: H2O2 oxidoreductase [EC 1.11.1.7]) was purified from a culture broth of an inkcap Basidiomycete, Coprinus cinereus S.F. Gray. A single component containing a low amount of carbohydrate was isolated by affinity chromatography on concanavalin A-Sepharose and crystallized from ammonium sulfate solution. The enzyme is an acidic protein (pI 3.5) and consists of a single polypeptide chain having the molecular weight of 41,600 daltons. The enzyme contains one protohemin per molecule and exhibits the characteristic absorption, circular dichroism, and magnetic circular dichroism spectra of a heme-protein. The Coprinus peroxidase forms two characteristic intermediate compounds, I and II, and the rate constants for hydrogen peroxide and guaiacol had similar values to those for higher plant peroxidases. The ferric enzyme formed a cyanide compound with a dissociation constant similar to those for higher plant enzyme, but the dissociation constant of the ferrous enzyme-cyanide was large. The chemical composition of Coprinus peroxidase showed 381 amino acid residues, 1 glucosamine, 3 true sugars, 3 calcium, and 1 non-heme iron other than 1 protohemin. The secondary structure of the fungal enzyme was very similar to that of horseradish peroxidase.

Agaricales↗
PubMed1988

The effect of H-2 compatibility on pancreatic beta cell survival in the nonobese diabetic mouse.

The effect of major histocompatibility (MHC) antigens on the survival of newborn pancreatic iso and allografts was assessed in the nonobese diabetic (NOD) mouse, which develops a spontaneous autoimmune diabetes. The NOD mouse (H-2Kd,Db) rejects skin allografts from CBA (H-2k) within a 12-day period, indicating normal immune function toward alloantigens. A pancreatic allograft into the NOD mouse represents a presumed first-set allogeneic response, as well as a possible second-set immune response to islets. To assess the effect of donor H-2 antigen and the influence of autoimmune disease on pancreatic graft survival, newborn pancreata from various strains of mice were transplanted into diabetic NOD mice treated with 40 mg/kg/day cyclosporine (CsA) that prevented skin allograft rejection. The grafts were then harvested at day 10 to histologically assess the graft viability. CBA pancreatic grafts, incompatible at all MHC loci, showed the least lymphocytic infiltration, and good donor beta cell survival. Furthermore, CBA newborn pancreata under appropriate conditions were able to cure or improve the diabetic condition in 3/6 NOD mice. In the graft sharing class I MHC antigens, lymphocytic infiltration was significantly increased, while the donor beta cell number clearly decreased. The intensity of the graft destruction was intermediate in C57BL/6 allografts sharing H-2Db antigen, and strongest in BALB/c allografts sharing H-2Kd and in NOD isografts. The results indicate that in diabetic NOD mice the CsA dose controlling allograft rejection is incapable of controlling antiislet immunity. This antiislet immunity appears to exert its effect in an H-2-restricted manner. These findings may have important implications for the transplantation of pancreatic tissue in treating type I diabetes in humans.

Animals↗
PubMed1988

Amplification of the hst-1 gene in human esophageal carcinomas.

The hst-1 gene, previously designated as the hst gene, and seven other oncogenes were examined for possible structural changes in esophageal, gastric and colorectal carcinomas by Southern blot hybridization. The hst-1 gene was amplified in eight (42.1%) of the nineteen esophageal squamous cell carcinomas and in all four metastatic tumors of lymph nodes. The degree of amplification ranged from two to eight times. Coamplification of the hst-1 and c-erbB-1 gene was found in one case of esophageal carcinoma. However, no amplification of the hst-1 gene was detected in gastric and colorectal carcinomas.

Adult↗
PubMed1988

Levels of glutathione S transferase pi mRNA in human lung cancer cell lines correlate with the resistance to cisplatin and carboplatin.

The amounts of mRNA for glutathione S transferase pi (GST pi) were significantly lower in 3 human small cell lung cancer (SCLC) cell lines than in 3 non small cell lung cancer (NSCLC) cell lines. The sensitivities of the 3 SCLC cell lines to cisplatin and carboplatin were much higher than those of the 3 NSCLC cell lines. These results indicate that low levels of GST pi mRNA expression in SCLC cell lines inversely correlate to high sensitivity to cisplatin and carboplatin, and further suggest that GST pi may play an important role in intracellular inactivation of these drugs.

Carboplatin↗
PubMed1988

Coamplification of the hst-1 and int-2 genes in human cancers.

The hst-1 gene, previously designated the hst gene, was identified as a transforming gene by transfection assays of genomic DNAs from various types of human cancers. We analyzed for alterations of the hst-1 gene in 18 bladder cancers, 23 renal cell carcinomas and 5 esophageal cancers. Although rearrangement of the gene was not detected in any of these samples, amplification of the hst-1 gene was found in 4 samples of tumors, including an invasive bladder cancer, both primary esophageal cancer and its lymph node metastasis, and kidney metastasis of an esophageal cancer. The same degree of amplification of the int-2 gene, the product of which has significant homology with the hst-1-encoded protein, was also observed in all of these DNA samples with amplified hst-1 gene. This result indicates close chromosomal localization of the two genes, which were amplified as one amplification unit.

Cell Line↗
PubMed1988

Nucleotide sequences of cDNAs for human papillomavirus type 18 transcripts in HeLa cells.

HeLa cells expressed 3.4- and 1.6-kilobase (kb) transcripts of the integrated human papillomavirus (HPV) type 18 genome. Two types of cDNA clones representing each size of HPV type 18 transcript were isolated. Sequence analysis of these two types of cDNA clones revealed that the 3.4-kb transcript contained E6, E7, the 5' portion of E1, and human sequence and that the 1.6-kb transcript contained spliced and frameshifted E6 (E6*), E7, and human sequence. There was a common human sequence containing a poly(A) addition signal in the 3' end portions of both transcripts, indicating that they were transcribed from the HPV genome at the same integration site with different splicing. Furthermore, the 1.6-kb transcript contained both of the two viral TATA boxes upstream of E6, strongly indicating that a cellular promoter was used for its transcription.

Amino Acid Sequence↗
PubMed1988

Morphological studies on the paraneuron in spontaneously hypertensive rats.

Some of the paraneuronic cells in SHR in the prehypertensive stage were studied and compared to cells of the control. In the adrenal medulla, the area of the norepinephrine storing cell islets of SHR was about twice the size. The number of both the norepinephrine storing granules and vesicles in the cytoplasm was increased. In the anterior pituitary, percentage of the ACTH producing cell of SHR was increased. In the enterochromaffin cell, the average number of argyrophilic cells through the gut was larger in SHR. In the mast cells, an increased number of intrathyroidal mast cells was observed. These paraneuronic cells in SHR were considered to be hyperplastic and/or overactive from early stage after birth.

Adrenal Medulla↗
PubMed1988

Heterogeneity of lung cancer cells with respect to the amplification and rearrangement of myc family oncogenes.

Seventy lung tumors from 53 patients were analysed for alterations of myc family oncogenes, c-myc, N-myc and L-myc, to evaluate when activation of these genes occurs during tumor development. The 53 cases were 17 small cell carcinomas (SCCs), 18 adenocarcinomas, 12 squamous cell carcinomas (SqCs), 4 large cell carcinomas and 2 adenosquamous carcinomas. Either N-myc or L-myc was amplified in 4 of the 17 (one N-myc and 3 L-myc) SCCs (24%), while c-myc was amplified in 3 of the 12 SqCs (25%). In one SCC, amplification of N-myc was found in the primary tumor, a pulmonary hilar lymph node metastasis and a pleural metastasis, but not in a liver metastasis or a para-aortic lymph node metastasis. In one SqC, c-myc was amplified in a pleural metastasis and a lymph node metastasis, but not in the primary tumor. In 2 cases of SCCs, amplification or rearrangement of c-myc was detected only in the cell lines, but not in the original tumors taken from the same individuals. These results indicate that tumor cells were heterogeneous for amplification and rearrangement of myc family oncogenes, and suggest that activation of these oncogenes in SCCs and SqCs occurs not at the time of malignant transformation but during tumor progression.

Chromosome Mapping↗
PubMed1988

hst-1 transforming protein: expression in silkworm cells and characterization as a novel heparin-binding growth factor.

A protein encoded by an hst-1 transforming gene was expressed in silkworm-derived BmN cells and secreted into the culture medium using a recombinant baculovirus vector. The strong affinity for heparin of the secreted protein made it possible to purify the hst-1 protein to homogeneity in a two-step procedure. The purified hst-1 protein has a molecular weight of 18,000 and stimulates both DNA synthesis in NIH3T3 cells and human umbilical vein endothelial cell proliferation. In addition, morphological changes and anchorage-independent growth of NIH3T3 cells are induced by this product. These results show that the hst-1 transforming protein is a novel heparin-binding growth factor as predicted by nucleotide sequence analysis.

Animals↗
PubMed1988

[Studies on hst, a transforming gene which belongs to a new superfamily of growth factors].

The hst gene was originally identified in surgically obtained human gastric mucosae as a transforming gene which could transform NIH3T3 cells morphologically. The hst cDNA clone was synthesized from mRNA of one of the NIH3T3 transformants. A human leukocyte genomic library was screened with this cDNA clone, and an hst genomic fragment was obtained. This genomic fragment itself had transforming activity, and the protein coding sequences were proved to be completely identical to those of the cDNA clone prepared from mRNA of the NIH3T3 transformant. This fact suggests that rearrangement or other structural alterations in the coding sequence are not required for the activation of the hst gene. The predicted hst protein consists of 206 amino acids and has a significant homology (40-50%) to fibroblast growth factors and int-2 protein. They together make up a new superfamily of growth factors and transforming genes.

Amino Acid Sequence↗
PubMed1988

[Aortic valve replacement in children associated with enlargement of aortic annulus].

Between February, 1983 and August, 1987, twelve children, aged from 2 years to 16 years, underwent aortic valve replacement associated with enlargement of aortic annulus successfully. According to the form of the left ventricular outflow tract obstruction, enlargement of aortic annulus was performed by Konno procedure in eight cases, by Nicks procedure in three cases and by Manouguian procedure in one case. In Manouguian procedure, mitral valve replacement associated with enlargement of mitral annulus was carried out simultaneously. In Konno and Manouguian procedures, the diameter of aortic annulus was enlarged from 180% to 200% compared with the original annular size, whereas in Nicks procedure, the diameter was enlarged around up to 110%. St. Jude Medical valve, of which size ranged from 21mm to 25mm, was employed in these procedures. All these children survived operation, and the post-operative follow up period ranged from 1 month to 55 months. There was one late death eleven months after Konno procedure because of respiratory failure resulting from pulmonary hypertension which persisted postoperatively. The remaining eleven children are surviving well after procedure. These results suggest that aortic valve replacement associated with enlargement of aortic annulus is an acceptable procedure in children with small aortic annulus or sub-aortic stenosis.

Adolescent↗
PubMed1988

Genetic alterations of the c-erbB-2 oncogene occur frequently in tubular adenocarcinoma of the stomach and are often accompanied by amplification of the v-erbA homologue.

We analyzed for alterations of the c-erbB-2 oncogene in 35 human stomach cancers and 8 cell lines derived from human stomach cancer. Amplification of c-erbB-2 was found in approximately 40% (5/13) of the tubular adenocarcinomas of the stomach examined, including 4 of 10 fresh tumors and one of 3 cell lines, but not in other histological types of stomach cancer examined (0/30), including 25 fresh tumors and 5 cell lines. This result strongly suggests that amplification of c-erbB-2 occurs frequently in tubular carcinomas in stomach cancer. Rearrangement of c-erbB-2 was also detected in one tubular adenocarcinoma. The rearranged fragment carried the 3' half, but not the 5' sequence, of the c-erbB-2 gene. Furthermore, one of the cellular homologues of v-erbA was amplified in 3 of 4 fresh tumors carrying the amplified c-erbB-2 gene. Both c-erbB-2 and the v-erbA homologue were expressed in all the stomach cancer cell lines tested.

Adenocarcinoma↗
PubMed1988

Retrospective study on amplification of N-myc and c-myc genes in pediatric solid tumors and its association with prognosis and tumor differentiation.

DNA was extracted from formalin-fixed and paraffin-embedded tissues of 85 patients with pediatric malignant solid tumors which had been resected at surgery or obtained at autopsy during a 24-year period. The tumors examined included 25 rhabdomyosarcomas, 12 Wilms' tumors, 10 hepatoblastomas and 37 neuroblastoma group tumors. Neuroblastoma group tumors were subclassified into 25 neuroblastomas and 12 ganglioneuroblastomas among which 6 composite ganglioneuroblastomas were included. Sample blocks were selected from both tumors and normal tissues in the majority of cases. We were able to reliably detect N- and c-myc gene amplification in tumor DNA by dot blot-hybridization. The N-myc gene showed approximately from 3- to 500-fold amplification in 19 of 33 cases of stage IV neuroblastoma group tumor. All of these 33 patients had been intensively treated with chemotherapy and/or radiotherapy. The c-myc was amplified 8-fold in 1 case of rhabdomyosarcoma, but neither N-myc nor c-myc was amplified in any cases of Wilms' tumor or hepatoblastoma. We retrospectively examined the association among N-myc gene amplification, prognosis, and histologic subtype in 33 patients with stage IV neuroblastoma group tumors. The survival of the patients with N-myc gene amplification was shorter than that of the patients without amplification of N-myc (p less than 0.05). There was no significant difference in prognosis between the 2 histologic subtypes; neuroblastoma and ganglioneuroblastoma, and the cases of tumors with amplified N-myc showed shorter survivals for each subtype (p less than 0.05). In every case of neuroblastoma group tumor, the copy number of the N-myc gene was the same among primary site and multiple metastatic tumors, even when the lesions showed differences in histologic subtype like neuroblastoma and ganglioneuroblastoma.

Child↗