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S Mitsunaga

Publications and source records attributed to S Mitsunaga.

At least 55 records · Page 3Linked to original sources
PubMed1992

3,5-Dihydroxyphenyl-glycine: a potent agonist of metabotropic glutamate receptors.

An amino acid, 3,5-dihydroxyphenylglycine (DHPG) induced current responses in Xenopus oocytes expressing a metabotropic glutamate receptor clone mGluR1. Apparent EC50 of DHPG for mGluR1 was slightly lower than that of (+-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (ACPD). DHPG responses were partially inhibited by 2-amino-3-phosphonopropionic acid (AP-3). DHPG had no effect on ionotropic glutamate receptors whose expression was induced in the oocytes following injection of poly(A)+ mRNA of rat brains. In hippocampal slices, DHPG produced slow excitation of pyramidal cells, resulting from a depression of Ca(2+)-dependent K+ current and a voltage-dependent K+ current. These results indicate that DHPG is a specific and potent agonist of mGluRs.

2-Amino-5-phosphonovalerate↗
PubMed1991

[A clinicopathological study of thymomas, with special reference to evaluation of malignant grade by morphometric analysis].

To determine the factors influencing the extent and recurrence of thymoma, 31 cases of thymoma who had undergone complete resection were analyzed clinicopathologically with special reference to the nuclear area of epithelial cells. The mean tumor size and incidence of recurrence of stage III thymomas were significantly larger and higher than those of stage I thymomas. The nuclear area of epithelial cells of stage III thymomas (72.9 +/- 29.2 micron 2) was significantly larger than that of stage I thymomas (48.4 +/- 13.2 micron 2) or stage II thymomas (49.4 +/- 11.6 micron 2). The nuclear area of thymomas with recurrence (70.2 +/- 21.5 micron 2) was significantly larger than that of those without recurrence (50.2 +/- 12.8 micron 2). In 16 cases who were followed up for 5 years or more, the nuclear areas were over 50 micron 2 in all thymomas with recurrence, while in 8 of 11 thymomas without recurrence it was under 50 microns 2. These results indicated that the tumor size and nuclear area increased step-wisely in association with the advance of clinical stage and that the incidence of recurrence was related to not only clinical stage but also nuclear area. Thymomas with large nuclear area (over 50 microns 2) are considered to be a high-risk group of recurrence and should be carefully followed up.

Adult↗
PubMed1990

Detection of human T-cell leukemia virus type I (HTLV-I) provirus in an infected cell line and in peripheral mononuclear cells of blood donors by the nested double polymerase chain reaction method: comparison with HTLV-I antibody tests.

Human T-cell leukemia virus type I (HTLV-I) provirus DNA from the cultured cell line HUT 102 and from peripheral mononuclear cells (PBMC) of anti-HTLV-I antibody-positive Japanese blood donors was detected by the nested double polymerase chain reaction (PCR) method. This procedure consists of a first amplification and a second amplification with the products of the first amplification and primers interior to the first primers. Using this method, we demonstrated that it is possible to detect single-template DNA. Polyacrylamide gel electrophoresis of the nested double PCR products, with our primers, revealed three bands with excess amounts of template DNA, two bands with moderate amounts, and a single band with limited amounts. The amount of provirus in PBMC was roughly estimated from the results of the nested double PCR. Particle agglutination (PA) assays and indirect immunofluorescence testing (IF) with mixed MT-2 cells and Molt-4 cells as targets to detect anti-HTLV-I antibody were performed, and the results were compared with those of the nested double PCR of the pX region. None of the 101 PA-negative samples were positive in either the IF or PCR test. Of the 155 samples that were antibody positive by the PA assay, 57 were positive by both PCR and IF. Furthermore, the results of the IF and PCR tests coincided completely. It was therefore concluded that the IF method is most appropriate for confirmation of the PA assay currently used in most diagnostic laboratories and blood centers.

Base Sequence↗
PubMed1990

[Effect of ethanol injection in tracheal large cell carcinoma--a case report].

A 66-year-old woman was admitted with dyspnea. A tracheal tumor was found by bronchofiberscopy, and histological examination revealed large cell carcinoma. The tumor obstructed nearly 90% of her tracheal lumen, so we performed intratumoral ethanol injection. The tumor became almost completely necrotic, and obstruction of her airway markedly improved. No serious complication was found. Intratumoral ethanol injection was very effective and safe in this case. This is the fifth report of undifferentiated carcinoma of the trachea in Japan.

Aged↗
PubMed1988

Effect of recombinant human interleukin 2 on the growth of a BALB/c sarcoma induced by Moloney murine sarcoma virus.

The effect of in vivo administration of recombinant interleukin 2 (rIL2) on the growth of a primary female BALB/c sarcoma induced by Moloney murine sarcoma virus (M-MSV) was studied. Although low-dose administration of (6,000 JU/mouse x 14 days) rIL2 had no effect on the growth of the tumors, high-dose (15,000-80,000 JU/mouse x 14 days) intraperitoneal inoculation of rIL2 induced tumor regression, dose-dependently. Tumors in mice which received 80,000 JU/mouse/day of rIL2 regressed completely 2 weeks after the initiation of treatment. The survival rates of the treated groups were significantly higher than those of the control group. A time course experiment disclosed that the effect of rIL2 was restricted only to the group in which rIL2 treatment started 8 days after the inoculation of M-MSV. The cytotoxic activity of regional lymph node lymphocytes from rIL2-treated mice was demonstrated against primary culture of M-MSV-induced sarcoma but not against syngeneic tumor induced by methylcholanthrene (Meth A). The effect of rIL2 was partially blocked by the administration of anti-IL2 receptor antibody. Immunohistochemical examination revealed that infiltration of Thy1.2+Lyt1+2- (helper/inducer subset) lymphocytes into the tumor tissue was prominent in mice which received high-dose rIL2. The results indicated that IL2 induced regression of M-MSV-induced sarcoma mainly through activation of IL2-receptor-positive helper T cells in the tumor tissues and of killer cells in the draining lymph nodes.

Animals↗
PubMed1986

[Radioresistant elements in adenocarcinoma of the uterus].

Radioresistant elements in adenocarcinoma of uterine cancer were studied using SKG-3a and HEC-59 cell lines as spheroids and monolayer culture. Dose-survival curves for monolayer cultured SKG-3a and HEC-59 cells were almost similar at acute exposure. On the other hand, as spheroids grown to 300 microns in diameter, dose-survival curves for SKG-3a cells were biphasic and those for HEC-59 were monophasic. The increased shoulder in survival curves proved the contract effect of both cells. Conventionally fractionated irradiation promoted shrinkage and disintegration of spheroids as the dose was increased. All SKG-3a spheroids were destroyed over 60 Gy, but some of HEC 59 spheroids survived over 68 Gy at the total dose. The total dose at disintegration-50% was 40 Gy in SKG-3a and 48 Gy in HEC-59 spheroids. In a comparison of single with 5-fractionated irradiation, fractionation induced an increase in radioresistance of adenocarcinoma cells. The maximum recovery-dose of HEC-59 cell as spheroids was 0.4 Gy and that of SKG-3a was 0.28 Gy. The magnitude of PLD-repair in HEC-59 cells was greater than that in SKG-3a. In conclusion, the PLD-repair and contact effect could be more important factors than the hypoxic element in the acquisition of radioresistance in adenocarcinoma cells as a solid tumor under fractionated irradiation.

Adenocarcinoma↗
PubMed1985

[Studies on the significance of PLD repair for radioresistance in human uterine adenocarcinoma cells].

Relationships between radioresistance of uterine adenocarcinoma cells and potentially lethal damage repair (PLDR) was studied using four human uterine carcinoma cell lines (HeLa S3, HEC-59, SNG-M and SKG-3a). The magnitude of PLDR was estimated by colony formation assay using cell densed and nutrition deficient cultured cells and transplanted cells in nude mice. PLDR of cultured cells and HeLa S3 cells in nude mice almost finished by 6 hours after irradiation. The magnitude of PLDR of HeLa S3 cells in vitro was almost the same 4-fold ratio as in vivo after radiation exposure at a dose of 5 Gray. This suggests that PLDR in vitro is correlated to that in vivo. Dose-surviving relationships demonstrated that radioresistance of four cultured cells was chiefly expressed as Do and Dq values in hit-theory and the magnitude of their radioresistance was as follows: HEC-59 greater than SNG-M greater than HeLa S3 greater than SKG-3a. On the other hand, the magnitude of their PLDR was as follows: HEC-59 greater than SNG-M greater than HeLa S3 greater than SKG-3a. This proved that the magnitude of radioresistance is correlated to that of PLDR and the more radioresistant adenocarcinoma cells have greater PLDR than squamous cell carcinoma cell. In conclusion, PLD repair may be an important cause of radioresistance in human uterine adenocarcinoma cells.

Adenocarcinoma↗
PubMed1983

Effects of contact lens wear on mitosis of corneal epithelium and lactate content in aqueous humor of rabbit.

Various types of contact lenses, i.e., poly-methyl-methacrylate hard lenses, poly-2-hydroxyethyl-methacrylate soft lenses and two kinds of gas-permeable hard lenses with different permeabilities to oxygen, were placed on one eye of the albino rabbit for varying lengths of time. Using the fellow eye as the control, studies were carried out of the effects of the lens wear on the mitosis in the corneal epithelium and the lactate concentration in the aqueous humor. The contact lens wear suppressed the mitosis and increased the concentration of aqueous lactate, the degree of changes being greater as the permeability of the lens to oxygen decreased and the period of wear became longer.

Animals↗
PubMedDate not supplied

Videokeratography for quantitative surface analysis of used soft contact lenses.

The greater utilization of soft contact lenses calls for the development of new and objective methods of evaluating the optical performance of the different lens types, in situ. We used videokeratography to examine the surface topography of soft contact lenses that had been worn for more than 1 year on 27 eyes of 23 patients, and compared the resulting color-coded maps and topographic indices as well as contact lens-corrected visual acuities, with those obtained with new replacement lenses on the same eyes. Visual inspection of the color-coded maps revealed differences in the surface characteristics of the used and new lenses. Comparison of quantitative indices including the SAI (Surface Asymmetry Index), IAI (Irregular Astigmatism Index), SRI (Surface Regularity Index), and SDP (Standard Deviation of Powers) showed that asymmetry, surface irregularity, potential visual acuity (derived from the SRI), and corneal power distribution were significantly poorer with the used lenses than with the new (P = 0.0001). The videokeratoscope is useful for evaluating the soft contact lens surface in situ, as an indicator of optical quality; it also permits the objective evaluation of lens cleaning techniques.

Adolescent↗
PubMedDate not supplied

Restricted use of T-cell receptor V beta genes in posttransfusion graft-versus-host disease.

BACKGROUND: Posttransfusion graft-versus-host disease (PT-GVHD) is a pathophysiological process of the immune system. Mature donor T cells that have survived the host defense mechanisms recognize recipient allo-antigens through antigen-specific T-cell receptors and mount an immune attack against certain host antigens. STUDY DESIGN AND METHODS: To characterize the T cells involved in PT-GVHD, expression of the T-cell receptor V beta genes in peripheral blood T cells isolated from four PT-GVHD patients was analyzed. T-cell receptor beta chain cDNA derived from mRNA extracted from peripheral blood lymphocytes was amplified by an inverse polymerase chain reaction method, and the cDNA was subsequently cloned and sequenced. RESULTS: The cDNA clones derived from patients with PT-GVHD showed remarkable differences in the distribution of T-cell receptor V beta gene use from that in normal controls. Very restricted T-cell receptor V beta gene repertoires and preferential expression of certain V beta gene segments were revealed in the peripheral blood lymphocytes of each patients. Shared V beta gene use among the patients was not observed, probably because of HLA differences among the patient-donor combinations. CONCLUSION: This restricted use reflected in vivo expansion of a limited number of engrafted T-cell clones at the onset of PT-GVHD and suggested that those oligoclonal donor T cells may be involved in the induction of PT-GVHD.

Aged↗
PubMedDate not supplied

Tear volume in relation to contact lens wear and age.

We examined the tear volume of the inferior conjunctival sac in relation to patient age and complications of contact lens wear using a special phenol red thread test. Records of patients who had undergone this test between 1984 and 1987 were reviewed. Based on the wet length of the thread, three groups were defined: 9 mm or less, 10-14 mm, and 15 mm or more. Those patients who showed consistent results over three or more separate testings were selected for this study. A total of 11,336 eyes met this criterion. A confidence interval of 95% was established as a basis for comparison of the groups. We found that the percentage of eyes with 9 mm or less of wet length increased with the age of the subject group. Likewise, the percentage of each age group with 15 mm or more of wet length steadily decreased among progressively older groups. Eyes wearing PMMA lenses with 9 mm or less of wet length showed the highest incidence of superficial punctate keratitis (SPK) and erosion. The group of eyes wearing high-DK lenses with 15 mm or more of wet length showed the lowest incidence of SPK and erosion.

Adolescent↗