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Biomedical subjects

M Matsuyama

Publications and source records attributed to M Matsuyama.

At least 55 records · Page 3Linked to original sources
PubMed1996

Mapping of two genetic loci, Ten-1 and Ten-2, associated with thymus enlargement in BUF/Mna rats.

The thymoma-prone BUF/Mna rat is a useful model for human thymoma. Thymoma develops spontaneously in these rats at an incidence of nearly 100%. At pre-thymoma age, BUF/Mna rats have extremely large thymuses when compared with those of rats of the other strains, suggesting the presence of genes that regulate the thymus enlargement. We performed linkage study to identify the genetic loci associated with thymus enlargement in {(WKY/NCrj x BUF/Mna) F1 x BUF/Mna} backcross rats. Linkage study showed the significant associations between thymus size and markers on Chromosomes (Chrs) 1 and 13, suggesting the presence of two genes, Ten-1 and Ten-2, which regulate the thymus enlargement. Ten-1 was located between myosin light chain, muscle 2 (MYL2) and D1Mgh11 loci on Chr 1, and Ten-2 was located between synaptotagmin II (SYT2) and D13N2 loci on Chr 13.

Animals↗
PubMed1996

Establishment and characterization of high- and low-lung-metastatic cell lines derived from murine colon adenocarcinoma 26 tumor line.

We established and characterized high- (LuM1) and low-lung-metastatic (NM11) cell lines derived from murine colon adenocarcinoma 26 tumor line. LuM1 cell line was established as a clonal cell line from a cultured cell mixture derived from a lung-metastatic nodule after 7 sequential subcutaneous transplantations of lung-metastatic tumors in the abdominal wall of BALB/c mice. NM11 cell line was established from a cultured cell mixture derived from a subcutaneous transplant of murine colon adenocarcinoma 26 tumor cells. LuM1 cells showed marked spontaneous lung metastases, but NM11 cells rarely did. High invasive potential of LuM1 cells was revealed by in vitro invasion assay using Matrigel reconstituted membranes. Rapid retraction was observed in monolayers of human umbilical vein endothelial cells and bovine aortic endothelial cells when LuM1 cells were added on the monolayers. Gelatin zymography and immunochemical examinations with monoclonal antibodies against gelatinase B (Mr 95,000 type IV collagenase) showed secretion of large amounts of the gelatinase by LuM1 cells.

Adenocarcinoma↗
PubMed1996

Distinct distribution of protein disulfide isomerase family proteins in rat tissues.

We investigated the distribution of protein disulfide isomerase (PDI) family proteins PDI, ERp72, and ERp61 in rat tissues and compared their localization by immunohistochemical double staining. The extent of their expression was diverse in different cell types, although they were ubiquitously distributed in a wide variety of cell types. Prominent staining for all three proteins was detected in thyroid follicular epithelia, tracheal mucous gland cells and chondrocytes, and chief cells and mucous neck cells of the stomach. Hepatocytes, neuronal cells in brain and spinal cord, and pancreatic acinar cells were also consistently and uniformly stained, but with low intensity. On the other hand, distinct differences were observed for the expression of the three proteins in plasma cells, pancreatic islet cells, goblet cells, and Paneth's cells of intestines, seminiferous epithelia, and salivary gland ductal epithelia. The similarities and differences in the distribution of the three proteins provide helpful clues to their biological functions.

Amino Acid Sequence↗
PubMed1996

[Surgical treatment for recrudescent Stanford type A early closing dissection].

Two cases of recrudescent Stanford type A dissection were reported. They had non-opacified false channel on their initial CT and aortography. The first case was 65-year-old woman having a stable blood pressure and no chest pain after admission. However, recrudescent opacified false lumen was found at the mid-ascending aorta about three weeks later. She received ascending aortic replacement on 26th day after onset. The second case was 66-year-old woman having a unstable blood pressure and having periodic chest pain and back pain after admission. CT and angiography performed on the 41th day after onset revealed recrudescent descending aortic dissection and ulcer like projection at mid-ascending aorta. The ulcer like projection increased in size gradually. Ascending aorta replacement was performed on 110th day after onset. Two cases had a good post operative days. Some cases of Stanford type A early closing aortic dissection had recrudescent dissection later, even if they had a stable course after onset. Thus, careful follow up for long term is essential in these cases

Aged↗
PubMed1996

[HELP syndrome and anesthetic management].

From January 1990 to December 1994, 24 parturients were diagnosed as having HELLP syndrome alone or combined with preeclampsia/eclampsia among 8,224 patients who were delivered at our institution. They consisted of 14 primiparous and 10 multiparous patients. Mean maternal age was 28.9 +/- 3.3 and gestational age was 34.8 +/- 5.6 weeks. Of 24 parturients, 8 had vaginal delivery and the remaining 16 were delivered by caesarean section. Serious maternal morbidity included eclampsia (n = 3), preeclampsia (n = 18), renal failure (n = 5), hydrothorax (n = 4), and DIC (n = 1). There was no maternal death. There were 3 intrauterine fetal deaths and two neonatal deaths. Perinatal deaths were 2 (0.9%, 2/26). Three caesarean sections were performed under general anesthesia, and 13 under spinal anesthesia. In cases with apparent bleeding tendency, spinal and epidural anesthesia should be avoided. In providing general anesthesia, hypertension should be controlled, and the uterus is preferably dilated before the delivery and contracted there-after.

Adult↗
PubMed1996

[Preliminary screening for antiviral AIDS drugs. VII. Report for fiscal year 1994].

Preliminary screening of antiviral AIDS drugs has been carried out using three different in vitro assay systems. Among 246 samples of different origin tested, six were shown to inhibit the growth of HIV in vitro. Two of the positive samples have hopeful signs, as the ranges of effective doses are wider than those of most of positive samples which had been found by us.

Anti-HIV Agents↗
PubMed1995

Spatial and temporal expression of the ret proto-oncogene product in embryonic, infant and adult rat tissues.

Immunohistochemical analysis with the anti-Ret antibody was performed to investigate the expression of the c-ret proto-oncogene product (c-Ret protein) in embryonic, infant and adult rat tissues. During embryogenesis, the c-Ret expression became detectable by day 11.5 in the developing peripheral and central nervous systems as well as in the excretory system. In the peripheral nervous system of the trunk, it was expressed at high levels in the enteric neuroblasts and the autonomic and dorsal root ganglia. c-Ret positive cells appeared in the mesenchyme around the foregut and the dorsal aorta at day 11.5 and formed the myenteric plexus of the whole embryonic gut and the sympathetic trunk at later stages respectively. Examination of the cranial region revealed that the c-Ret protein was expressed in neural crest cells migrating from rhombomere 4 at day 11.5 and then became positive in the facial, glossopharyngeal and vagus cranial ganglia at day 12.5-13.5. After day 16.5 of gestation, the c-Ret expression was also observed in the trigeminal ganglion. In the central nervous system, the c-Ret protein was expressed in the neuroepithelial cells of the ventral neural tube (day 11.5-14.5), the motor neurons of the spinal cord (day 18.5) as well as in the embryonic neuroretina (day 18.5). In addition to the nervous system, the c-Ret expression was detected in the nephric duct (day 11.5), the ureteric bud (day 13.5) and the collecting ducts of the kidney (day 16.5). After birth, neurons in the nervous systems mentioned above continued to express the c-Ret protein at variable levels while no c-Ret expression was observed in the kidney of adult rats. Furthermore, the c-Ret expression was found in the acinar cells of the salivary gland, the epithelial cells of the thymus and the follicular dendritic cells of the spleen and lymph node in infant and adult rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1995

Structure and promoter analysis of the cytochrome P-450 aromatase gene of the teleost fish, medaka (Oryzias latipes).

We isolated the structural gene encoding cytochrome P-450 aromatase (P-450arom), for the first time from a nonmammalian vertebrate, the medaka (a teleost fish, Oryzias latipes), using the rainbow trout P-450arom cDNA as a probe. The structure of the entire P-450arom gene, the nucleotide sequence of its 5' flanking region, and the transcriptional initiation sites were determined. The medaka P-450arom gene consists of nine exons, but spans only 2.6 kb, being much smaller than the human P-450arom gene (at least 70 kb), as a result of extremely small introns (medaka, 73-213 bp vs. human, 1.3-10 kbp). The splicing junctions are located at exactly the same positions as those found in the human P-450arom. The deduced amino acid sequence is 51-52% identical to those of mammals and chicken, and 75% identical to the rainbow trout amino acid sequence. Genomic Southern blots revealed the presence of a single medaka gene. Promoter analyses indicated two major transcription initiation sites 60 and 61 bp upstream from a putative initiation codon. The promoter region of medaka P-450arom gene also contains potential Ad4BP sites and estrogen responsive element (ERE) half-sites. These results suggest that the basic structural organization of P-450arom genes and the regulatory mechanisms of expression are well conserved throughout the vertebrates.

Amino Acid Sequence↗
PubMed1995

The characteristics of cultured mucosal cell sheet as a material for grafting; comparison with cultured epidermal cell sheet.

The characteristics of cultured mucosal cells from the oral mucosa were investigated and compared with those of cultured epidermal cells. Total cell counts showed that mucosal cells possessed greater proliferating ability than epidermal cells. The results of 3(4,5-dimethyle-thiazoyl-2-yl)2,5 diphenyltetrazolium bromide assay confirmed this observation and also suggested that the mucosal cells maintained biological activity longer than epidermal cells. The most important morphological characteristics of mucosal cells in culture were their low grade of differentiation. Interestingly, the epidermal cells showed enucleation and keratinization progressively during culture, whereas the mucosal cells showed no obvious enucleation when examined by light microscopy. Transmission electron microscopy showed a smaller number of desmosomes in cultured mucosal cells than epidermal cells. The results of this study reveal cultured mucosal cell sheets to be a possible material for grafting in addition to cultured epidermal cell sheets.

Cell Count↗
PubMed1995

Contraction potency of hypertrophic scar-derived fibroblasts in a connective tissue model: in vitro analysis of wound contraction.

Many investigators have reported that collagen gel contraction reflects the mechanism of wound contraction. By using a connective tissue model (CTM) of collagen gel lattice, we analyzed the contraction potency of fibroblasts that had been obtained from hypertrophic scar, normal skin, and normal oral mucosa. We then tried to analyze the mechanism of CTM contraction by immunofluorescent microscopic and transmission electron microscopic examinations. Hypertrophic scar-derived fibroblasts in CTM possessed the greatest contraction potency and the shortest lag time when compared with those of normal skin and normal oral mucosa-derived CTMs. It became clear that the initial contractive degree of CTM was closely related to morphological changes of fibroblast cells into bipolar and elongated shapes. Hypertrophic scar-derived fibroblasts elongated their processes faster, and their intracellular actin filaments were more numerous than those of normal fibroblasts. We believe that the hypertrophic scar-derived CTM is a useful pathological model for the research of wound contraction and hypertrophic scar formation.

Adolescent↗
PubMed1995

Genetic regulation of development of thymic lymphomas induced by N-propyl-N-nitrosourea in the rat.

To clarify the linkage between Hbb and Tls-1 (thymic lymphoma susceptible-1) loci and to investigate other loci concerned in thymic lymphomagenesis, the BUF/Mna rat, which is highly sensitive to the lymphomagenic activity of N-propyl-N-nitrosourea (PNU), the WKY/NCrj rat, reported to be resistant, and their cross offspring were subjected to genetic analysis. F1 hybrid and backcross generations were raised from the 2 strains, and 6 genetic markers including Hbb were analyzed in individuals of the backcross generation. However, no linkage between Hbb and Tls-1 loci could be demonstrated since WKY rats also developed a high incidence of thymic lymphomas in response to PNU. Nevertheless, thymic lymphomas developed more rapidly and reached a larger size in the BUF rats. F1 rats expressed a rather rapid and large tumor growth phenotype, while the [(WKY X BUF) X WKY] backcross generation consisted of rats with either rapidly growing or slowly growing tumors. It was thus concluded that rapid development of thymic lymphomas is determined by a gene, provisionally designated Tls-3. Analysis of the relationship between 6 genetic markers and development of thymic lymphoma in the backcross generation demonstrated that the Tls-3 locus is loosely linked to the Gc locus, suggesting a possible location on rat chromosome 14. Tls-3 may not be identical with Tls-1 and other genes known to be relevant to thymic tumors, but its relationship with Tls-2 remains obscure.

Animals↗
PubMed1995

Mechanism of activation of the ret proto-oncogene by multiple endocrine neoplasia 2A mutations.

Transforming activity of the c-ret proto-oncogene with multiple endocrine neoplasia (MEN) 2A mutations was investigated by transfection of NIH 3T3 cells. Mutant c-ret genes driven by the simian virus 40 or cytomegalovirus promoter induced transformation with high efficiencies. The 170-kDa Ret protein present on the cell surface of transformed cells was highly phosphorylated on tyrosine and formed disulfide-linked homodimers. This result indicated that MEN 2A mutations induced ligand-independent dimerization of the c-Ret protein on the cell surface, leading to activation of its intrinsic tyrosine kinase. In addition to the MEN 2A mutations, we further introduced a mutation (lysine for asparaginic acid at codon 300 [D300K]) in a putative Ca(2+)-binding site of the cadherin-like domain. When c-ret cDNA with both MEN 2A and D300K mutations was transfected into NIH 3T3 cells, transforming activity drastically decreased. Western blot (immunoblot) analysis revealed that very little of the 170-kDa Ret protein with the D300K mutation was expressed in transfectants while expression of the 150-kDa Ret protein retained in the endoplasmic reticulum was not affected. This result also demonstrated that transport of the Ret protein to the plasma membrane is required for its transforming activity.

3T3 Cells↗
PubMed1995

[Multiparametric cytometric analysis of hepatocellular carcinoma and its allied lesions combining DNA ploidy analysis with morphometry using DAPI/HP double staining].

Hepatocellular carcinomas (HCC) of various differentiation, Edmondson (Edm) grade I-IV, often based upon viral infectious hepatitis transformed through regeneration, nodular and/or dysplastic adenomatous hyperplasia. Aspiration cytology, even needle biopsy for such lesions, is very difficult to interpret. We have been studying multiparametric cytologic analysis using DAPI/Hematoporphyrin (HP) staining for the cece samples provided from exactly trimmed 50-microns thick paraffin sections, employing a new software program which we developed, combining DNA ploidy and cell protein content analysis with morphometry. DAPI indicates DNA content and nuclear size and HP indicates cell protein content and cell size. From 21 cases of HCC, 43 nodules or masses including multiple lesions and nodule in nodule were analyzed. Surrounding non-neoplastic hepatic tissues were examined as the control specimens. On DNA histogram, cases with the peak over 2.4 c are identified as aneuploid (Aneupl). Cases of Edm I, or II, 6 of 8 samples showed Aneupl., all of 11 cases of Edm II, 11 cases of Edm III, and one of Edm IV showed Aneupl. Multinodular foci in the same cases and also nodule in nodule often showed different modes of Aneupl. This suggested heterogenetic carcinogeneity. Noncarcinomatous foci often showed Aneupl. modes, which may indicate malignant transformation or malignant potential.

Carcinoma, Hepatocellular↗
PubMed1995

[Premedication in children: a comparison of oral midazolam and rectal bromazepam].

Seventy-seven children for minor surgery of less than 90 minutes in duration were divided into two groups; one group received midazolam syrup and the other received bromazepam suppository. The sedative effect before or after the induction of the anesthetic, the effect on the circulatory system, and the prolongation of the sedative effect after surgery were studied. Regarding the sedative effect before or during the induction of anesthesia, both medications were effective with no significant difference between the two groups. However, the bromazepam suppository had a significantly better sedative effect 1 or 2 hours after the surgery. In children under 4 years of age, the sedative effect during the induction was obtained by administering midazolam syrup before the surgery. It is indicated that midazolam syrup is superior to the bromazepam suppository in children under 4 years of age.

Administration, Oral↗