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Biomedical subjects

S Kawamura

Publications and source records attributed to S Kawamura.

At least 235 records · Page 13Linked to original sources
PubMed1994

High expression of the CD30 molecule in human decidual cells.

CD30 is a receptor-type membrane protein that belongs to the nerve growth receptor superfamily. It is expressed on Hodgkin's cells and activated lymphocytes, as well as in some human malignancies including malignant lymphomas, embryonal carcinomas, and other mesenchymal tumors. However, whether it is expressed in normal tissues remains unclear. To study the expression and biological function of CD30, we first examined various human tissues by immunohistochemistry. The monoclonal antibody Ber-H2 intensely stained the membranes of decidual and endometrial cells with decidual change in frozen sections. Western blots of these tissues with Ber-H2 revealed bands of 120, 105, and 90 kd as found on CD30-expressing cells. Northern blots of these tissues using a CD30 cDNA probe detected mRNAs of the same molecular mass and variety as those in the positive control cell line HUT 102. These results indicated that CD30 is expressed in human endometrial tissue with decidual change and imply that CD30 expression in endometrial tissue is induced by hormonal control.

Base Sequence↗
PubMed1993

Recoverin has S-modulin activity in frog rods.

In vertebrate photoreceptors, light induces hydrolysis of cGMP by activating cGMP phosphodiesterase (PDE), which results in closure of the cGMP-activated cation channel. During light adaptation, the cytoplasmic Ca2+ concentration decreases, and this decrease is one of the underlying mechanisms of light adaptation. Sensitivity-modulating protein (S-modulin) is a Ca(2+)-binding protein involved in light adaptation in frog rods; it regulates both the light sensitivity of PDE and the lifetime of activated PDE by controlling rhodopsin phosphorylation in a Ca(2+)-dependent manner. Recoverin has been reported as a Ca(2+)-dependent regulator of guanylate cyclase in bovine rods (Dizhoor, A. M., Ray, S., Kumar, S., Niemi, G., Spencer, M., Brolley, D., Walsh, K. A. Philipov, P. P., Hurley, J. B., and Stryer, L. (1991) Science 251, 915-918). Here, we show that recoverin has similar activity as S-modulin, and the amino acid sequences of both proteins are similar. The results strongly suggest that recoverin is bovine S-modulin and regulates PDE activation.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1993

Molecular characterization of the red visual pigment gene of the American chameleon (Anolis carolinensis).

The red sensitive visual pigment of the American chameleon, Anolis carolinensis, is unique in having absorption maximum some 50 nm further into the red than any other terrestrial vertebrate examined. We report here the isolation and sequence determination of the genomic DNA clone for the Anolis red visual pigment gene. Phylogenetic analysis shows that this gene is most closely related to the gecko green and chicken red visual pigment genes. We identified nine Anolis-specific amino acid replacements, seven of which reside in transmembrane domains and might contribute to the red-shift of the Anolis visual pigments.

Amino Acid Sequence↗
PubMed1993

Clinical significance of morphologic classification of coronary arterial segmental stenosis due to Kawasaki disease.

Coronary arteriograms obtained in 1,392 patients from a cohort of 4,562 with Kawasaki disease showed 395 to have coronary arterial lesions. The specific lesions, known as segmental stenoses, were observed in 62 patients, involving 68 coronary arterial branches. The lesions involved the right coronary artery in 56 cases (14.2% of the group with arterial lesions) and the left coronary artery in the other 12 (3% of the overall group with arterial lesions). Three morphologic variations were observed. Braid-like lesions accounted for 15 lesions, involving the right coronary artery and occurring < 2 years after the onset of Kawasaki disease. Bridging vessels were observed in 40 of 68 arterial lesions, 30 of which involved the right coronary artery. Of these bridging vessels, 86% were present within 4 years of onset of the disease. Pericoronary communications were observed in the remaining 13 of 68 lesions, 11 involving the right coronary artery and appearing at variable intervals, but usually significantly later than the other lesions. Myocardial ischemia was found at the first study in 60% of braid-like lesions, but in only 29% of the lesions at follow-up studies. Of bridging vessels or pericoronary communications, 95 and 77%, respectively, were found to have produced ischemia in the initial study, which persisted in 78 and 77%, respectively. There are 3 different mechanisms involved in the formation of segmental stenosis, with different prognoses for the clinical course of myocardial ischemia.

Child, Preschool↗
PubMed1993

Rhodopsin phosphorylation as a mechanism of cyclic GMP phosphodiesterase regulation by S-modulin.

During light-adaptation by the vertebrate eye, the rods are desensitized and the light response is accelerated. When light is absorbed by the rods, a phosphodiesterase is activated that hydrolyses cyclic GMP. A light-induced decrease in cytoplasmic Ca2+ concentration is part of this light-adaptation process. The protein S-modulin (M(r) 26,000) is known to increase the fraction of light-activated cyclic GMP-phosphodiesterase (PDE) at high Ca2+ concentrations in frog rod photoreceptors. Here I present evidence that S-modulin lengthens the lifetime of active PDE (PDE*) at high Ca2+ concentrations. These S-modulin effects are observed in the physiological range of Ca2+ concentration (30 nM to 1 microM; half-maximum effects at 200-400 nM). At the high Ca2+ concentrations at which S-modulin prolongs the lifetime of PDE*, S-modulin inhibits rhodopsin phosphorylation (half-maximum effect at approximately 100 nM Ca2+). ATP is necessary for the S-modulin effects on PDE activation. I therefore conclude that the Ca(2+)-dependent regulation of PDE by S-modulin is mediated by rhodopsin phosphorylation. This regulation seems to be the principal mechanism of light adaptation in vertebrate photoreceptors.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1993

Tolerance and cross-tolerance to the antinociceptive effects of [D-Arg2]-dermorphin tetrapeptide analogue and morphine.

Rats were given repeated subcutaneous injections of [D-Arg2, Sar4]-dermorphin (1-4) [DAS-DER-(1-4)] and/or morphine over a period of 4 or 7 days. Antinociception was determined at 90 min for DAS-DER (1-4) and 30 min for morphine after each morning injection (9:00 a.m.), using the tail-flick and digit pinching tests in rats. Subcutaneous administration of DAS-DER (1-4) and morphine produced the development of antinociceptive tolerance, respectively. A marked tolerance to DAS-DER (1-4) and morphine was seen in rats made tolerant to morphine. However, administration of morphine produced no significant decrement in the antinociceptive activity in rats made tolerant to DAS-DER (1-4). These results suggest that the site of action of DAS-DER (1-4) may be more limited than that of morphine in the nociceptive pathways, for lack of its antinociceptive efficacy in morphine-tolerant rats.

Amino Acid Sequence↗
PubMed1993

AT-877, a Ca2+ antagonist, fails to reduce infarct size following rat middle-cerebral artery occlusion.

We investigated the effects of AT-877, a Ca2+ antagonist, on rat middle-cerebral artery occlusion. All rats had 6-h ischemia, and treated animals received either 3 or 10 mg/kg AT-877 s.c. just after the occlusion. Control animals received an equal volume of the vehicle. Prior to sacrifice, significant changes in the decrease of blood pressure and the increase of plasma glucose were observed in the treated rats. Although the infarct size tended to decrease, this decrease was not significant. Only when the blood pressure- or plasma glucose-matched subgroups were compared, the infarct volume decreased significantly in the drug-treated animals. Thus, AT-877 failed to reduce ischemic brain damage unless the blood pressure or plasma glucose were controlled.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1993

Experimental model of carotid artery thrombosis in rats and the thrombolytic activity of YM866, a novel modified tissue-type plasminogen activator.

We compared the thrombolytic activity of a novel modified t-PA, YM866, with that of t-PA in a rat model of electrically-induced thrombosis. Histological examination revealed the thrombus to be composed mainly of platelet clumps. Measurement of the decrease in carotid blood flow showed that complete occlusion occurred within 14 min. At 10 min after the induction of thrombus, a test drug (YM866, t-PA, or saline) was administered by i.v. bolus injection under heparinization (300 IU/kg, i.v.). Both YM866 and t-PA exhibited dose-dependent thrombolytic activity; the reperfusion rate of YM866 was twice that of t-PA. There was no significant difference in time to reperfusion between the agents, but YM866 showed a greater improvement in patency status after successful thrombolysis than t-PA. Plasma fibrinogen fell slightly but significantly (14% of baseline value) in animals given 1 mg/kg of YM866. All groups of rats showed a significant decrease in carotid artery blood flow at 1 hr after successful reperfusion or injection of the drug, but this decrease showed significant recovery in animals given 1 mg/kg of YM866. These results suggest that YM866 by single bolus injection is a superior thrombolytic agent to t-PA, and that YM866 can improve the patency status after successful thrombolysis. Furthermore, this platelet-rich thrombosis model permits continuous observation of the process of thrombus formation and subsequent thrombolysis and provides a useful tool for the screening and evaluation of efficacy of new antithrombotic agents.

Animals↗
PubMed1993

Subjective results of laser surgery for allergic rhinitis.

Inferior turbinates of 389 patients with perennial allergic rhinitis were vaporized by a defocused carbon dioxide (CO2) laser beam, using specially designed handpieces. This laser surgery can be done under local anesthesia as an outpatient procedure, with no pain or bleeding. One month after laser surgery, 78% of 389 patients had excellent or good results, while 21 had no improvement, subjectively. Seventy-two of 389 patients were followed for over 2 years, and 61 of the 72 had excellent or good results. Twenty-seven of the 72 cases need revaporization because of recurrence. Patients with relapse less than one year after surgery had little improvement in subjective symptoms, even after revaporization; while patients with relapse more than one year after surgery responded well, and long-term results were favorable. All things considered, laser surgery is an effective treatment for perennial allergic rhinitis.

Follow-Up Studies↗
PubMed1993

New retinoids inhibiting the growth of human acute promyelocytic leukemia cell line HL-60 without inducing differentiation.

A series of acid homologs with longer side chain length was synthesized and their biological activities to inhibit growth and to induce differentiation of human acute promyelocytic leukemia cell line HL-60 were analyzed. It was found that ethyl alpha-retinylidene propionate (E) shows interesting activity. This compound inhibited growth of HL-60 cells with almost the same potency of retinoic acid. However, unlike retinoic acid, the potency of this compound to induce differentiation of HL-60 cells into neutrophiles was almost negligible. Ethyl alpha-retinylidene propionate (E) is an unprecedented retinoid which inhibits growth of HL-60 cells without inducing cell differentiation. The Z isomer [ethyl alpha-retinylidene propionate (Z)] also showed similar unique effects on HL-60 cells. Interestingly, both of the E and Z isomers of alpha-retinylidene propionic acid showed only very weak activities to inhibit growth and to induce differentiation of HL-60 cells. It was suggested that ethyl alpha-retinylidene propionate acts on HL-60 cells in the intact form without suffering hydrolysis, and also that the ester group plays important role for the unique activity. Biological activities of retinylidene acetic acid (E and Z) which lacks methyl group at alpha-position of alpha-retinylidene propionic acid, on HL-60 cells were weaker than those of the isomers of alpha-retinylidene propionic acid. Esterification of the isomers of retinylidene acetic acid resulted in further decrease of biological activities. Biological activities of ethyl retinoate on HL-60 cells were also very weak. It was indicated that methyl group present at alpha-position of ethyl alpha-retinylidene propionate plays an important role for the unique biological activity. It was further indicated that the effect of esterification of carboxyl group of retinoids on the biological activity is not constant, but varies depending on the structure. Pretreatment of HL-60 cells with ethyl alpha-retinylidene propionate (E) apparently did not influence the process of induction of differentiation of HL-60 cells into neutrophiles by retinoic acid. It was further shown that ethyl alpha-retinylidene propionate (E) prolongs the time necessary for induction of differentiation of HL-60 cells by retinoic acid, but does not influence the level of final rate of differentiation.

Cell Differentiation↗
PubMed1993

[Shock wave therapy of the rabbit VX2 bladder cancer--THP-ADM concentration in the tissue after combination therapy of THP-ADM and shock wave].

Tissue concentration of THP-ADM was analysed after the administration of THP-ADM with or without exposure of high energy underwater shock waves (SW) to rabbit bladder VX2 cancer. THP-ADM was administered intravenously (2 mg/kg) or into the urinary bladder (10 mg/body). After the administration of THP-ADM, SW was exposed (6,000-10,000 shots) to VX2 bladder cancer or normal bladder tissue. One hour later, THP-ADM tissue concentration was measured by high performance liquid chromatography method. In intra-venous group, THP-ADM concentration of cancer tissue was significantly lower (p < 0.02) in SW group than that of non-SW group. In bladder instillation group, THP-ADM concentration of normal bladder tissue was significantly higher (p < 0.02) in SW group than that of non-SW group and the average concentration of cancer tissue was higher about three times in SW group than that of non-SW group.

Administration, Intravesical↗
PubMed1993

[Immunohistochemical study of globotriaosyl ceramide (Gb3) in testicular tumors].

Testicular tumor tissues and various normal tissues were examined by immunohistochemical techniques for expression of globotriaosylceramide (Gb3) using anti-Gb3 monoclonal antibody (1A4). In formalin fixed paraffin-embedded specimens (31 cases), Gb3 was positive for every kind of elements of testicular germ cell tumors, especially it's incidence of positive staining were 100% in seminomas (16/16) and embryonal carcinomas (6/6). On the other hand, four cases of testicular malignant lymphoma were all negative for Gb3, and some normal testicle, liver, kidney, pancreas, spleen, ileum and rectum showed very weak reactivity with 1A4. In frozen materials (10 cases), similar incidence of positive staining with that of paraffin-embedded specimens were observed in drying only manner, 4% parafolm-aldehyde fixation following drying and 10 min. of acetone fixation following drying. Incidence of very strong staining in testicular germ cell tumors were as follows, 7/10 in 4% parafolmaldehyde fixation, 6/10 in drying only, 4/10 in 10 min. of acetone fixation and 7/22 in paraffinembedded specimens. Fixation with 30 min. of acetone fixation and 10 min. of 90% ethanol and treatment with 10 min. of chloroform:methanol (2:1, v/v) extremely decreased the reactivity with 1A4, suggesting that Gb3 exists mainly as glycolipid. Gb3 may thus be a useful histological marker for testicular germ cell tumor, and the tissue should be treated with the process of freezing followed by 4% parafolm-aldehyde fixation, drying only or 10 min. of acetone fixation, and formalin fixed paraffin-embedded specimens were also available enough.

Biomarkers, Tumor↗
PubMed1993

Therapeutic effect of intradermal injections with difucosyl lactosamine (dimeric Lex) on patients with rheumatoid arthritis.

As reported by us, a new myeloid cell population with an oncofetal membrane marker, dimeric Lex (di-Lex; III3FucV3 FucnLc6), was found in the epiphyseal bone marrow adjacent to the involved joints of patients with severe rheumatoid arthritis (RA). Patients with RA received intradermal (id) injections of di-Lex incorporated in liposome or of high molecular weight glycoprotein, or tumor associated carbohydrate antigen (TCA), containing the same carbohydrate epitope as di-Lex. The epiphyseal myeloid cells were reduced or sometimes eliminated during id injection. In random trials of id injection, observation under clinical and laboratory conditions showed improvement in 63% (17/27) of the patients treated for 6 months with appropriate doses of di-Lex (III3FucnLc4), and in 72% (31/43) of those treated with an identical protocol for TCA. However, id injection with monomeric Lex had no effect.

Adult↗