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Biomedical subjects

H Matsui

Publications and source records attributed to H Matsui.

880 records · Page 49Linked to original sources
PubMedDate not supplied

Effects of iron chelates on the transferrin-free culture of rat dermal fibroblasts through active oxygen generation.

Effects of nonchelating and chelating agents at 10 mM on the serum-free culture of rat dermal fibroblasts were investigated. A strong iron-chelating agent, iminodiacetic acid (IDA), and a weak one, dihydroxyethylglycine (DHEG), decreased iron permeation into preconfluent fibroblasts. A weak iron-chelating agent, glycylglycine (GG), a nonchelating agent, N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES), and human apotransferrin (10 micrograms/ml) increased the permeation with time. Iron may be essential for survival of fibroblasts because subconfluent fibroblasts exposed to 100 microM FeSO4 in combination with transferrin, HEPES, or GG significantly decreased to release lactate dehydrogenase into the medium. Superoxide dismutase and dimethyl sulfoxide blocked the enzyme release, suggesting that superoxide and hydroxyl radical induce cellular damage but hydrogen peroxide (H2O2) generated by superoxide dismutation does not. GG significantly reduced H2O2 cytotoxicity. DHEG acted as a potent promoter of the iron-stimulated cellular damage if ascorbate or H2O2 was added to the medium. FeSO4 and FeCl3 (50 to 100 microM) individually combined with IDA maximally promoted fibroblast proliferation. Ascorbate increased formation of thiobarbituric acid-reactive substances from deoxyribose in the medium supplemented with FeSO4 and either IDA or DHEG. Conversely, ascorbate decreased the formation in the medium with FeSO4 and with or without other agents. Fibroblast proliferation may thus be stimulated through the active oxygen generation mediated by a redox-cycling between Fe3+ and Fe2+, which are dissolved in the medium at a high concentration, rather than through delivery of iron into the cells.

Animals↗
PubMedDate not supplied

Structure and expression of a cloned cDNA for human interleukin-2.

A cDNA coding for human interleukin-2 (IL-2) has been cloned from a cDNA library prepared from partially purified IL-2 mRNA. The DNA sequence codes for a polypeptide which consists of 153 amino acids including a putative signal sequence. A biologically active polypeptide, characteristic of human IL-2, was produced when the cDNA was fused to a simian virus 40 promoter sequence and used to transfect cultured monkey COS cells.

Amino Acid Sequence↗
PubMedDate not supplied

Application of gas chromatographic determination of organotin compounds to basic research on the metabolism of triphenyltin chloride in rats.

This paper describes the application of gas chromatographic determination of organotin compounds to basic research on the metabolism of triphenyltin chloride in rats. Phenyltin compounds were extracted (as chloride) from rat-liver homogenates and subcellular fractions with hydrochloric acid and n-hexane-benzene (3:2, containing 0.05% tropolone). These organotin compounds were pentylated with a Grignard reagent prior to capillary gas chromatography. The absolute detection limits were in the range of 3.6 to 4.4 pg as tin. The absolute recoveries of phenyltin compounds added to homogenized whole liver and each subcellular fraction sample ranged from 73.9 to 97.4%. The intracellular distribution of triphenyltin and its metabolites in the liver was observed for 72 h after a single oral dose of triphenyltin chloride was given to rats. The tri-, di-, and monophenyltin compounds in the fractions reached maximal amounts about 6, 48, and 72 h after administration, respectively. Also, the concentrations of monophenyltin compounds in the liver were typically lower than to those of di- and triphenyltin compounds. The highest contents of di- and triphenyltin compounds per protein were found in the microsomal fractions.

Animals↗
PubMedDate not supplied

Prevalence of hepatitis C virus antibody in an area endemic for hepatitis B virus and human T cell leukaemia virus.

To clarify the prevalence of concurrent infection with hepatitis C virus (HCV), hepatitis B virus (HBV) and human T cell leukaemia virus (HTLV), we measured HCV antibody in the population of a district endemic for HBV and HTLV infection. Blood samples were collected in June 1990 from 579 inhabitants of four islands of Uwa Bay in the southwest of Ehime Prefecture in Japan. Anti-HCV antibody against C100-3 protein was detected using an enzyme-linked immunosorbent assay kit (Ortho Diagnostics). Thirteen of the 579 inhabitants (2.2%) were positive for anti-HCV, and this prevalence rate was not significantly different from the frequency of anti-HCV in Tokyo blood donors. A total of 11% (64 of 579) of the subjects were positive for HBsAg and 3.3% (19 of 579) were positive for anti-HTLV. These frequencies of HBsAg and anti-HTLV positivity were distinctly higher than the respective means of Japanese. All anti-HCV positive individuals were negative for HBsAg and anti-HTLV, while 54% (7 of 13) had increased alanine aminotransferase levels. These data suggest that the prevalence of HCV infection is not high even in an area endemic for HBV and HTLV infection.

Adolescent↗
PubMedDate not supplied

Stabilization in microsomal membranes of the fifth transmembrane segment of the Na+,K(+)-ATPase alpha subunit with proline to leucine mutation.

We have reported that the fifth transmembrane segment of the Na+,K(+)-ATPase alpha subunit could not be inserted into microsomal membranes when it was synthesized from the truncated alpha 1 cDNA. In this study, three proline residues in the segment were changed into leucine residues by site-directed mutagenesis. Replacement of all three proline residues by leucine residues allowed the insertion of this segment and its translocation. This result confirms our previous finding and demonstrates that three proline residues in the fifth transmembrane segment prevent insertion of the segment into the membrane.

Amino Acid Sequence↗
PubMedDate not supplied

Effects of tumor cell-derived interleukin 1 alpha on invasiveness of metastatic clones of murine RCT sarcoma through endothelial cells.

Interleukin 1 alpha (IL-1alpha) production and invasiveness through mouse lung endothelial cells (MLE) were investigated in high-metastatic RCT+ and low-metastatic RCT- clones established from poorly differentiated murine sarcoma. Apparently, a higher level of IL-1alpha was derived from RCT+ cells than from RCT- cells. In an invasion assay, the number of cells which penetrated the MLE monolayer in RCT+ was significantly greater than that in RCT-. The invasiveness of RCT+ and RCT- cells was stimulated by additional recombinant mouse IL-1alpha (rIL-1alpha) in a dose-dependent manner. Anti-mouse IL-1alpha monoclonal antibody (anti-IL-1alpha mAb) significantly inhibited the invasiveness of RCT+ and RCT- cells through the MLE monolayer. However, in RCT+ cells these effects were higher than in RCT- cells. In an attachment assay, the ability of RCT+ cells to attach to the MLE monolayer was significantly higher than that of RCT- cells. The attachment ability of RCT+ and RCT- cells to the MLE monolayer was significantly increased by the pretreatment with rIL-1alpha in a dose-dependent manner. In a retraction assay, conditioned medium of RCT+ stimulated the retraction of the MLE monolayer more markedly in comparison with conditioned medium of RCT-. The retraction of the MLE monolayer was stimulated by additional rIL-1alpha in a dose-dependent manner. The increased retraction of the MLE monolayer was closely associated with the enhancement in tumor cell invasiveness. These findings suggest that IL-1alpha derived from RCT+ and RCT- cells might contribute to the enhancement of tumor cell invasion by stimulating the attachment to the MLE monolayer and retraction of the MLE monolayer.

Animals↗
PubMedDate not supplied

Successful arthroscopic treatment of pigmented villonodular synovitis of the knee in a patient with congenital deficiency of plasminogen activator inhibitor-1 and recurrent haemarthrosis.

We report the arthroscopic treatment of pigmented villonodular synovitis (PVNS) in a 13-year-old Japanese boy with congenital partial deficiency of plasminogen activator inhibitor-1 (PAI-1). He was admitted to our hospital with recurrent haemarthrosis of his right knee. Characteristic abnormalities of fibrinolysis included shortened euglobulin lysis time, low PAI-1 activity and low PAI-1 antigen levels. In addition, levels of "active PAI" in the plasma, which is a measure of total PAI bound to exogenous plasminogen activator, were very low. These parameters remained low after venous occlusion. The diagnosis of PVNS was established by synovial membrane biopsy, and arthroscopic synovectomy was performed with adjuvant administration of intravenous tranexamic acid. Subsequent bleeding episodes have been well controlled by oral administration of tranexamic acid on demand.

Adolescent↗
PubMedDate not supplied

Age-related changes of human lens epithelial cells in vivo.

We examined the density and morphology of lens epithelial cells (LECs) in vivo in a group of normal volunteers and cataract patients by using a newly developed noncontact specular microscope. There was a statistically significant decrease in the cell density of LECs in a group of cataract patients over the age of 80 years. The coefficient of variation of the cell area and the number of large black spots that were observed in the enhanced specular images were not related to aging or cataract formation. Our data indicate that the cell density of LECs decreases after reaching the age of 80, but cataract formation does not affect the cell density or the coefficient of variation of the cell area until the age of 80.

Adolescent↗
PubMedDate not supplied

Role of the tensor tympani muscle in eustachian tube function.

In order to determine the role of the tensor tympani muscle in Eustachian tube function, pressure changes in the external and middle ear of 13 cats were measured under four experimental conditions. It was revealed that contraction of the tensor tympani muscle during swallowing did not result in any tympanic pressure rise which might assist in tubal ventilation. Acoustic stimulation was then used to measure consistent contraction of the tensor tympani muscle. Combined contraction of the tensor veli palatini and tensor tympani muscle under the condition of positive tympanic pressure failed to open the tube. It was concluded that the tensor tympani muscle might not play any part in tubal function.

Acoustic Stimulation↗
PubMedDate not supplied

Transient hypoplastic anemia caused by primary human parvovirus B19 infection in a previously untreated patient with hemophilia transfused with a plasma-derived, monoclonal antibody-purified factor VIII concentrate.

BACKGROUND: Modern plasma-derived clotting factor concentrates are produced using various virus-inactivation protocols and are assumed to be safer than they were previously with regard to the risk for transmitting viral infections such as human immunodeficiency virus, hepatitis B, and hepatitis C. The risks from viruses that are relatively resistant to the current inactivation procedures remain uncertain. PATIENT: A 7-year-old with mild hemophilia A who had not been previously infused with any blood products was treated with a plasma-derived, monoclonal antibody-purified factor VIII concentrate to cover orthopedic surgery after traumatic fracture of his left arm. RESULTS: A typical primary human parvovirus (HPV)-B19 infection was observed associated with transient hypoplastic anemia. Retrospective studies including serologic examination and polymerase chain reaction analysis confirmed that the HPV-B19 infection was transmitted by the factor VIII concentrate. CONCLUSIONS: Clotting factor concentrates for the treatment of hemophilia retain a risk for HPV-B19 contamination. HPV-B19 viral infection might induce hypoplastic anemia in these patients, particularly during enhanced hemopoiesis after acute blood loss.

Anemia, Aplastic↗
PubMedDate not supplied

The effects of recombinant human erythropoietin on autologous blood donation in rheumatoid arthritis patients with anaemia.

OBJECTIVES: The effect of recombinant human erythropoietin (rHuEPO) treatment on autologous blood donation was evaluated in anaemic patients with rheumatoid arthritis (RA) undergoing total joint replacement surgery. METHODS: A total of 56 total knee or hip joint replacement operations were performed in the knee or hip joint in 36 anaemic RA patients (hemoglobin (Hb) concentration < 11.0 g/dl]. All of the patients received intravenous rHuEPO at a dose of 100-200 units/kg body weight three times a week for 3 weeks. An autologous blood donation of 800-1200 g was the goal for each patient. A refractory case was defined as a patient whose Hb level did not increase to 10.0 g/dl after 3 weeks of treatment with rHuEPO. The objective signs of arthritis were assessed by the Lansbury activity index (AI). During the treatment period, the patients underwent weekly hematological analyses, including routine hematology, serum iron, serum ferritin, C-reactive protein (CRP), and serum erythropoietin levels. RESULTS: The response to rHuEPO treatment was determined, and blood donation was possible in 47 of 56 joint replacements. In the other 9 operations, donation was not possible due to a poor response to rHuEPO. The mean Hb level before treatment in the refractory group (8.3 g/dl) was significantly lower than that in the responsive group (10.4 g/dl, p = 0.0002). During the treatment period, the mean erythropoietin level was above the normal limit in the refractory group. The mean AI for the refractory group tended to be lower than that in the responsive group. The mean pre-treatment CRP (6.4 mg/dl) and erythrocyte sedimentation rate (ESR) (87.1 mm/h) levels in the refractory group were significantly higher than those in the responsive group (CRP: 3.2 mg/dl, p = 0.008, ESR: 52.6 mm/h, p = 0.01). CONCLUSIONS: The control of disease activity prior to rHuEPO treatment is considered to a prerequisite for autologous blood donation. In addition, severe anaemia (Hb concentration < 8.0 g/dl) appears to be another risk factor for refractoriness to rHuEPO treatment with the present protocol. A higher rHuEPO dose (> 200 units/kg/3 times a week for three weeks) was considered to be necessary in the refractory group.

Adult↗
PubMedDate not supplied

Desmoplastic response in scirrhous gastric carcinoma: imbalance between collagen synthesis and degradation.

BACKGROUND: Scirrhous gastric carcinoma is characterized by a marked deposition of collagen in the stroma and has a very poor prognosis. MATERIALS AND METHODS: To elucidate the fibrotic mechanism in scirrhous gastric carcinoma, we measured the activities of the collagen synthetic enzyme, prolyl 4-hydroxylase (P4H) and the collagen degrading enzymes, interstitial collagenase and type IV collagenase, in tissue from patients with advanced gastric carcinoma. Concentrations of P4H and tissue inhibitor of metalloproteinases-1 (TIMP-1) in the sera of patients with gastric carcinoma were measured using sandwich enzyme immunoassay systems. We performed immunohistochemical analysis for TIMP-1. RESULTS: Enzyme activities of P4H, interstitial collagenase and type IV collagenase in the tumor samples of scirrhous gastric carcinoma were significantly lower than those of non-scirrhous gastric carcinoma (p < 0.01). Serum concentration of TIMP-1 in patients with diffuse type carcinoma was significantly higher than in patients with intestinal type carcinoma and control subjects (p < 0.05). We demonstrated stromal expression of TIMP-1 in scirrhous gastric carcinoma tissue. CONCLUSION: These data suggest that decreased collagenase activity and increased expression of TIMP-1 would result in collagen deposition in scirrhous gastric carcinoma tissue.

Adenocarcinoma, Scirrhous↗
PubMedDate not supplied

Characteristics of gastric mucus in elderly patients with gastric ulcers.

BACKGROUND/AIMS: Studies of the most important defensive factor, gastric mucus, in the treatment of gastric ulcers in elderly patients have been lacking. Therefore we focused on the changes in gastric mucus during the ulcer-healing process in elderly patients. METHODOLOGY: Twenty elderly patients (> or = 65 years old), and 20 younger patients (< 65 years old) with gastric ulcers were administered antisecretory agents for 24 weeks. Biopsies were taken from the antrum and body of the stomach, and the levels of gastric mucosal hexosamine and periodic acid-Schiff-positive gastric mucus were measured. RESULTS: In both groups, the hexosamine levels in the specimens from the body of the stomach declined during the healing process. The decrease was more marked in the elderly, and the recovery of this level was also slower than in the younger group. The periodic acid-Schiff-positive mucosal index was also lower in the elderly. A decrease in body periodic acid-Schiff-positive mucus was seen with treatment in both groups, but recovery was slower in the elderly group. CONCLUSIONS: A decrease in gastric mucus, as a gastric mucosal defensive factor, was seen in gastric ulcers in elderly patients. The potential usefulness of the administration of mucosal protective agents for elderly patients with gastric ulcers was suggested.

Adolescent↗
PubMedDate not supplied

Gene expression profiles in human BPH: utilization of laser-capture microdissection and quantitative real-time PCR.

Human benign prostatic hyperplasia (BPH) nodules consist of epithelium and stroma that have different properties functionally as well as morphologically. To investigate the molecular profiles of the prostate gland, separate examination of these components are necessary. Laser-capture microdissection (LCM) is a newly-developed device which enables one to dissect interesting parts of tissues under the microscope. In the current work we studied the gene expression profiles of prostatic epithelium and stroma using LCM. Androgen receptor (AR), estrogen receptor alpha and beta (ER alpha and ER beta), progesterone receptor (PR) and 5-alpha reductase type I and type II (5alphaR I and 5alphaR II) gene expressions were studied by RT-PCR. All of these genes were expressed both in the epithelium and stroma. Furthermore, AR transcript was quantified by quantitative real-time PCR. AR transcript ranged from 302 to 1440 copies per 10(5) GAPDH copies and from 257 to 3223 copies per 10(5) GAPDH copies in the epithelium and stroma, respectively. Thus, LCM and quantitative real-time PCR are powerful tools for molecular analysis of heterogeneous tissues including prostate gland.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMedDate not supplied

Triiodothyronine decreases the accumulation of 1,2-diacylglycerol in rat hearts.

1,2-Diacylglycerol (DAG) is an intracellular signal mediator that may initiate protein synthesis and cardiac hypertrophy via activation of protein kinase C. The amounts of 1,2-DAG and its fatty acid components in the myocardium was assessed and compared with the concentrations of RNA and DNA in cardiac hypertrophy induced by administering triiodothyronine (T3) with and without cycloheximide, an inhibitor of protein synthesis. After the first injection of T3 no cardiac hypertrophy was observed, and there were no differences in myocardial 1,2-DAG content or in RNA and DNA concentrations. Cardiac hypertrophy was present on days 3 and 7 after a daily injection of T3. Myocardial RNA concentration was increased by 26% on day 3 and by 34% on day 7, whereas the myocardial 1,2-DAG content was decreased by 8% on day 3 and by 24% on day 7. Pretreatment with cycloheximide of T3-treated rats prevented the development of cardiac hypertrophy, but elevated the RNA concentration and lowered the 1,2-DAG content compared with the findings in T3-treated rats. Analysis of the fatty acid components of 1,2-DAG revealed that the amounts of 16:0, 18:1 and 18:2 were decreased, accompanied by an elevation of RNA concentration and a decrease in 1,2-DAG content. It seems that RNA synthesis preceded the alteration in 1,2-DAG. These findings suggest that 1,2-DAG is not involved in the initiation of cardiac hypertrophy induced by T3, but is affected by the enhanced concentration of RNA resulting from the introduction of thyroid hormones into the myocardium.

Animals↗