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T Terao

Publications and source records attributed to T Terao.

At least 145 records · Page 8Linked to original sources
PubMed1998

Determination of peptide phi angles in solids by relayed anisotropy correlation NMR.

A solid state NMR method is presented for determination of a backbone dihedral angle phi in peptides, being based on the previously reported method, relayed anisotropy correlation (RACO) NMR [Y. Ishii et al., Chem. Phys. Lett. 256 (1996) 133]. In the present method, the 15N-1H and the 13C-1H dipolar tensors in the 1H-15N-13C-1H system are two-dimensionally (2D) correlated via polarization transfer from 15N to 13C under magic angle spinning (MAS). This method was applied to N-acetyl[1,2-13C,15N]D,L-valine, and the H-C-N-H dihedral angle was determined to be 154.0 +/- 1.4 degrees or 206.0 +/- 1.4 degrees, the former agreeing with the X-ray value of 154 +/- 5 degrees.

Anisotropy↗
PubMed1998

Identification of structural domains in inter-alpha-trypsin involved in calcium oxalate crystallization.

The urinary glycoprotein that inhibits calcium oxalate (CaOx) crystallization in vitro shows a structural similarity to urinary trypsin inhibitor (UTI; recently termed bikunin), the light chain of inter-alpha-trypsin inhibitor (I alpha I). The functional domains of I alpha I involved in its inhibitory activity of CaOx crystallization have been investigated using isolated intact domains of I alpha I produced from controlled proteolytic digests of the protein. The fragments investigated include the heavy chains of I alpha I, UTI, chondroitinase AC-treated UTI, and the carboxyl-terminal domain of UTI (termed HI-8). The effects of I alpha I and its fragments on the inhibitory activity of CaOx crystallization were evaluated in vitro using CaOx crystal aggregation and growth assays, and seeded crystal generation assay as well as using crystal matrix protein generation assay. UTI, but not the heavy chains of I alpha I, had a discernible effect on CaOx crystallization inhibitory activity. Less requirement of the carbohydrate moiety of UTI is implicated by the observation that chondroitinase AC-treated UTI fragment was also found to inhibit CaOx crystallization with almost the same activity as UTI. HI-8 also efficiently inhibited CaOx crystallization, while I alpha I showed a weak inhibitory activity. The results are almost consistent with a seed crystal generation assay and a crystal adsorption inhibition assay, in which I alpha I or its derivatives inhibits prothrombin fragment 1 (F1) adsorption to CaOx crystals. In conclusion, these results suggest that the part of the I alpha I protein responsible for inhibition of CaOx crystallization is the carboxyl-terminal domain of UTI.

Alpha-Globulins↗
PubMed1998

Decreased renal and hepatic blood flow with preeclampsia-like histologic changes was obtained by stimulation of the celiac ganglion with LPS.

Decreased renal and hepatic blood flow with preeclampsia-like histologic changes was developed by stimulation of the celiac ganglion with lipopolysaccharide (LPS) in pregnant rabbits. The renal and hepatic blood flow were measured after stimulation of the celiac ganglion with 10 microL (group 1), 100 microL (group II) and 300 microL (group III) of LPS (10 mg/mL conc.) and with 100 microL of normal saline (group IV). The bifurcation of the abdominal aorta was also stimulated with 300 microL of LPS (group V). A control experiment was also done in this study (group VI). Histopathological studies of kidney and liver tissue were also performed in this protocol. A significant reduction in renal and hepatic blood flow was observed in pregnant rabbits with the times and dosage dependent on stimulation of the celiac ganglion by LPS. Stimulation of the bifurcation of the abdominal aorta with LPS could not produce any changes in renal and hepatic blood flow. Preeclampsia-like histologic changes of kidney and liver tissue were also observed. These results suggest that exogenous stimulation of the celiac ganglion causes decreased renal and hepatic blood flow, resulting in preeclampsia-like histologic changes of kidney and liver in pregnant rabbits.

Animals↗
PubMed1998

Anticoagulant activity in non-immunoglobulin fraction from plasma of patients with antiphospholipid syndrome.

Anticoagulant activity is present in non-immunoglobulin (IgG) fractions from plasma of patients with antiphospholipid syndrome (APS). Plasma from six patients with primary or secondary APS was passed through a protein A sepharose 4B column. Anticoagulant activity in IgG samples and non-IgG samples was determined by both dilute aPTT based clotting assay and by dilute PT based clotting assay. Thrombin generation was determined by prothrombinase complex assay in the presence of IgG sample or non-IgG sample. Anticoagulant activity was detected in the IgG samples with the dilute aPTT based clotting assay and in non-IgG samples with the dilute PT based clotting assay. The activity was not detected in IgG samples with the dilute PT clotting assay. Forty percent of total thrombin generation was inhibited in the presence of non-IgG samples although thrombin generation was not inhibited in the presence of IgG samples and beta2-glycoprotein I. The anticoagulant activity detected by dilute PT based clotting assay and prothrombinase complex assay was non-IgG, phospholipid-Ca++-dependent and beta2-glycoprotein I-independent. The role of non-IgG anticoagulants should be determined as well as the role of LA Igs antibodies in the mechanisms of thrombosis.

Anticoagulants↗
PubMed1998

Serological and immunohistochemical diagnosis of amniotic fluid embolism.

The purpose of this study was to evaluate whether serological assays and immunohistochemical staining, employing antibody TKH-2, are sensitive methods for the serological and histologic diagnosis of amniotic fluid embolism (AFE). TKH-2 is a sensitive antibody directed to sialyl Tn (STN), NeuAcalpha2-6GalNAc. Nineteen samples of maternal sera with clinical AFE and 120 control sera and 15 specimen of formalin-fixed, paraffin-embedded lung tissue sections were examined in this study. Tissue sections were stained using the streptavidin-biotin-immunoperoxidase method. The concentration of STN in serum was measured by an immunoradiometric competitive inhibition assay using the monoclonal antibody TKH-2 in a one-step procedure. Remarkable positive TKH-2 stainings were easily seen within the pulmonary vasculature in 14 of the 15 (93%) patients with AFE. The serum STN levels (mean+/-SD) in patients with AFE (110.8+/-48.1 U/ml) showed significantly higher concentrations compared with those of patients with non-AFE (17.3+/-2.6 U/ml) (p <0.01). Seventeen of 19 sera (89%) were diagnosed as AFE by serum TRH-2 level. We conclude that both TKH-2 immunostaining and serum STN assay are sensitive methods to diagnose patients with AFE.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1998

Vasospasms of cerebral arteries in hyperemesis gravidarum.

Hyperemesis gravidarum is associated with nausea and vomiting during the 1st trimester of pregnancy. We report 2 cases of hyperemesis gravidarum associated with vasospasms of cerebral arteries recognized by magnetic resonance imaging angiography. The hyperemetic condition of the patients improved after fluid and electrolyte replacement therapy.

Adult↗
PubMed1998

Studies on the role of adhesive proteins in maintaining pregnancy.

UNLABELLED: It is well known that maternal fibrinogen (Fg) and factor X III are essential for maintaining early pregnancy. We studied their role by analysis of clinical reports and immunohistochemical investigation. METHODS: (1) We analyzed the pregnancy cases of congenital afibrinogenemia and congenital factor X III deficiency. (2) Immunohistochemical staining of Fg, subunit A of factor X III (X IIIA) and fibronectin (Fn) were performed in the human implantation site, placenta, and endometrial cells cultured in serum-free medium. RESULTS: (1) Afibrinogenemia needed to be administrated Fg from 4 weeks' gestation (4 wG), and factor X III deficiency needed factor X III concentrate from 5 wG, in order to prevent abortion. (2) Implantation tissues: Fg, cellular X IIIA and Fn were present at the decidual stroma around invasive cytotrophoblasts at 5 wG. X IIIA-positive cells coincided with LN-5-positive macrophages. Placenta: Fg, cellular X IIIA and Fn were present in the decidual layer. Endometrial culture cells: Fn was secreted by spindle-like shaped cells. X IIIA was secreted by round-shaped cells. CONCLUSION: Maternal Fg and factor X III are essential just after 4-5 wG, and in that period they and Fn are present abundantly in decidual stroma around invasive cytotrophoblasts. It is concluded that when cytotrophoblasts invade endometrium maternal Fg, factor X III and Fn are concerned with cytotrophoblasts' anchoring as adhesive proteins.

Abortion, Spontaneous↗
PubMed1998

Eclamptic plasma stimulates norepinephrine release in cultured sympathetic nerve.

The purpose of the present study was to evaluate the effect of plasma from eclamptic and preeclamptic patients on cultured sympathetic nerve. Sympathetic neurons from 12- to 14-day-old chick embryos were cultured; the neurons were then stimulated with 50% plasma from eclamptic, preeclamptic, hypertensive, normotensive pregnant, hypertensive, and normotensive nonpregnant women (n=7). Similarly, neurons were individually incubated with mixtures of 50% corresponding plasma with 0.25% bupivacaine or bupivacaine only (n=7). Furthermore, the effects of 1%, 10%, and 50% plasma from eclamptic, preeclamptic, and normotensive pregnant patients (n=7) were also evaluated. Norepinephrine concentrations were measured by high-performance liquid chromatography. Electron microscopic studies of nerve cells were also performed. Stimulation with plasma from eclamptic and preeclamptic women significantly increased norepinephrine concentration (P<0.0001) compared with control. The release of norepinephrine was found to be concentration-dependent. Conversely, norepinephrine secretion was significantly hampered by bupivacaine treatment (P<0.0001). Electron microscopic studies in eclamptic and preeclamptic plasma-stimulated nerve cells showed that perikarya were in close contact with each other and with nerve cell processes. After treatment with bupivacaine, nerve cells were irregular in shape and the cell membranes were demyelinated. These results suggest that eclamptic and preeclamptic plasma has an excitotoxic effect on sympathetic nerve via axoplasmic membrane depolarization, thus increasing norepinephrine secretion that is blocked by bupivacaine. A preeclamptic condition may be improved by depression of sympathetic nerve stimulation.

Adult↗
PubMed1998

Effect of dehydroepiandrosterone sulfate on interleukin-8 receptor during cervical ripening.

We investigated the effects of dehydroepiandrosterone sulfate (DHA-S) on the production of interleukin-8 (IL-8) and expression of the interleukin-8 receptor (IL-8 R) in human cervical tissue. DHA-S increased the levels of IL-8 in cultured human cervical fibroblasts and in the supernatant in a time- and dose-dependent manner. DHA-S induced IL-8 and IL-8 R expression in human cervical fibroblasts and human pregnant cervical tissue at term in a dose-dependent manner. In addition, it induced the expression of IL-8 R in an explant culture of human cervical tissue and cultured human cervical fibroblasts in a time- and dose-dependent manner. However, dehydroepiandrosterone (DHA) only slightly induced the production of IL-8 and the expression of IL-8 R in the same cells and tissue. These results suggest that DHA-S up-regulates the autocrine system of IL-8 through the expression of IL-8 R.

Antigens, CD↗
PubMed1998

The kallikrein-kinin system, but not vascular endothelial growth factor, plays a role in the increased vascular permeability associated with ovarian hyperstimulation syndrome.

Ovarian hyperstimulation syndrome (OHSS) is a severe complication arising from controlled stimulation treatment. Vascular endothelial growth factor (VEGF) has recently emerged as an important factor which may be responsible for the hyperpermeability seen in OHSS. The purpose of the present study was to investigate and compare the mechanisms by which ascites in patients with OHSS and ovarian carcinoma induce increases in vascular permeability in an in vitro assay and an in vivo animal experiment. We found 8-fold lower VEGF levels in ascites from patients with OHSS than in those from patients with ovarian carcinoma. Although VEGF is produced by the ovaries, it is not necessarily the factor responsible for hyperpermeability. We also demonstrated that the vascular hyperpermeability produced by OHSS ascites was not abolished by specific neutralizing anti-VEGF antibodies, and that not all of the VEGF found in the ascites fluid is biologically active. Moreover, our results strongly suggest that the vascular permeability produced by OHSS ascites may depend on activation of the kallikrein-kinin system. Possible evidence for this phenomenon was obtained by demonstrating that the hyperpermeability caused by the ascites could be blocked by Trasylol (known to inhibit bradykinin synthesis) and potentiated by captopril (a kininase II inhibitor). Taken together, the results suggest that, although VEGF is found in ascites fluid from patients with OHSS, it is unlikely that the cause of OHSS involves VEGF production by the ovaries. The kallikrein-kinin system may be more important in the hyperpermeability seen in OHSS.

Adult↗
PubMed1998

Carbamazepine treatment in a case of musical hallucinations with temporal lobe abnormalities.

OBJECTIVE: The aim of this paper is to describe a case of musical hallucinations with temporal lobe abnormalities responding to carbamazepine treatment. CLINICAL PICTURE: A 63-year-old woman suffered from musical hallucinations accompanied by mild left temporal spike activity. TREATMENT: She received carbamazepine treatment. OUTCOME: Four weeks of carbamazepine treatment diminished her musical hallucinations in parallel with the normalisation of her mild left temporal spike activity. CONCLUSIONS: These findings suggest that carbamazepine can be an effective treatment for musical hallucinations with temporal lobe abnormalities.

Anticonvulsants↗
PubMed1998

Urinary trypsin inhibitor, a Kunitz-type protease inhibitor, modulates tumor necrosis factor-stimulated activation and translocation of protein kinase C in U937 cells.

Urinary trypsin inhibitor (UTI) is a Kunitz-type protease inhibitor. We have reported that UTI inhibited TNF-induced urokinase (uPA) production via a protein kinase C (PKC)-dependent mechanism. It is likely that UTI suppresses tumor cell invasion and metastasis by a mechanism, possibly by inhibiting uPA production. In the present study, we attempted to determine how UTI is associated with PKC, and how UTI is involved in uPA-dependent tumor cell invasion and metastasis. The increments of membrane-associated PKC activity by TNF were subsequently accompanied by a rapid loss of cytosol-associated PKC activity in U937 leukemia cells. Semi-quantitative immunoblotting of membrane and cytosol fractions showed that the translocation of PKC-alpha, -beta, and -epsilon were blocked by the addition of UTI in cells stimulated with TNF but not in cells stimulated with PMA, demonstrating that PKC itself is not sensitive to UTI. This effect was dependent on the carboxyl-terminus of UTI. In addition, UTI neither inhibited TNF binding to cellular receptors nor inactivate PKC and uPA activities directly. Taken together, the experiments suggest that the carboxyl-terminus of UTI may inhibit the PKC-signalling pathways upstream of diacylglycerol by a mechanism, possibly by interrupting the coupling of receptor and effector systems. UTI was shown to have an interesting new function besides being a protease inhibitor. This is the first report that UTI has a selective inhibition of TNF-activated PKC. We conclude that UTI suppresses tumor cell invasion and metastasis by a mechanism that UTI inhibits TNF-stimulated uPA production via a PKC-dependent mechanism.

Blotting, Western↗
PubMed1998

Production of a hybrid protein consisting of the N-terminal fragment of urokinase and the C-terminal domain of urinary trypsin inhibitor in Escherichia coli.

We have constructed a hybrid protein (ATFHI) consisting of an N-terminal fragment from urokinase (ATF) and HI-8, which is the C-terminal domain of urinary trypsin inhibitor. The fusion genes for the hybrid proteins were engineered by PCR and cloned into expression plasmids. Under the control of the tac promoter, fusion genes were efficiently expressed in Escherichia coli. The hybrid proteins, produced as inclusion bodies in E. coli, were refolded by a dialysis method and purified by ion-exchange chromatography. ATFHI exhibited bifunctional activity related to antimetastatic effects: the urokinase receptor-binding activity of ATF and the inhibitory activity of HI-8 on plasmin.

Animals↗
PubMed1998

How to lower perinatal mortality? Perinatal care in Japan.

OBJECTIVE: To review the 30-year history of perinatal medical care in Japan, and the recently initiated regionalization system of perinatal centers, new technologies and treatments in obstetric and neonatal medicine developed in Japan. STATISTICAL DATA: Maternal and neonatal health statistics of Japan released by the Ministry of Health and Welfare, Japanese Society of Obstetrics and Gynecology, Japanese Pediatric Society, and Tokyo Women's Medical University. LABORATORY DATA: Serological assay and immunohistochemical staining employing TKH-2 antibody for the diagnosis of amniotic fluid embolism, and assaying granulocyte elastase as a specific inflammatory marker in mucous samples from the uterine cervical canal for the prediction of preterm labor or premature rupture of membranes. TREATMENTS: Urinary trypsin inhibitor (Urinastatin) for the prevention of preterm delivery, and a double-blind, placebo-controlled, randomized trial of antithrombin-III therapy in severe preeclampsia. CONCLUSION: Over the last 30 years, the statistical data of perinatal health care, such as maternal and perinatal mortality rates, have markedly improved in Japan. These results are supported by the advanced technologies and newly developed treatments in obstetric and neonatal medicine. The regionalization of perinatal centers, a national project in order to assure a systematic collaboration among primary, secondary, and tertiary centers, has just started in Japan. It also aims at systematization of the function of perinatal centers on the national level through the informative promoting action.

Female↗
PubMed1998

Carbamazepine-induced up-regulation of voltage-dependent Na+ channels in bovine adrenal medullary cells in culture.

Treatment of cultured bovine adrenal medullary cells with carbamazepine (CBZ) for 5 days caused an increase in catecholamine secretion induced by veratridine, an activator of voltage-dependent Na+ channels. However, no increase was stimulated by carbachol, an agonist of nicotinic receptors, or by 56 mM K+, a depolarizing agent that activates voltage-dependent Ca++ channels. CBZ (30 microg/ml) treatment enhanced veratridine-induced catecholamine secretion in a time-dependent manner (increases of 25%, 65% and 70% for 3, 5 and 7 days of treatment, respectively). CBZ treatment (5 days) increased veratridine-induced catecholamine secretion in a concentration-dependent manner (increases of 27%, 36%, 45% and 55% at 10, 15, 20 and 30 microgram/ml of CBZ, respectively). CBZ treatment also increased 22Na+ influx and 45Ca++ influx stimulated by veratridine. The stimulatory effect of CBZ treatment on catecholamine secretion was blocked by either actinomycin D or cycloheximide, an inhibitor of protein synthesis. Additive responses of catecholamine secretion and 22Na+ influx induced by veratridine were associated with combined exposure of the cells to CBZ and dibutyryl cyclic AMP. CBZ treatment (30 microg/ml, 5 days) significantly increased the specific binding of [3H]saxitoxin to cell membranes. A Scatchard analysis of [3H]saxitoxin binding revealed that CBZ increased the Bmax value without any change in the dissociation constant. These findings suggest that CBZ up-regulates the density and activity of voltage-dependent Na+ channels.

Adrenal Medulla↗
PubMed1997

Expanded CTG repeats in myotonin protein kinase suppresses myogenic differentiation.

A full-length mutant human myotonin protein kinase (MtPK) cDNA having a 46 expanded CTG-repeat size or a wild type containing 5 CTG repeats was stably transfected into mouse C2C12 cell line in order to explore the effects of the expansion mutation of trinucleotide repeats in the 3' untranslated region on developing myogenic cells. Each established clone expressed a human 70 kDa MtPK protein without proteolytic processing. Differentiation experiments indicated that stable mutant MtPK cDNA-transformants suppressed myogenic differentiation, whereas wild-type transformants exhibited almost normal myogenesis. The disturbance of the expression of neuronal nitric oxide synthase, a mediator of myoblast fusion, suggests that signal transduction system might be involved in the muscle manifestations of mutant MtPK.

Animals↗
PubMed1997

Urinary trypsin inhibitor suppresses the production of interstitial procollagenase/proMMP-1 and prostromelysin 1/proMMP-3 in human uterine cervical fibroblasts and chorionic cells.

The mechanisms by which urinary trypsin inhibitor (UTI) prevents preterm premature rupture of fetal membrane and premature cervical ripening were investigated. We, therefore, examined the effects of UTI on the production of matrix metalloproteinases (MMPs) which closely participate in the breakdown of extracellular matrix in cultured human uterine cervical fibroblasts and human chorionic cells. UTI suppressed specifically the production of interstitial procollagenase/proMMP-1 and prostromelysin 1/proMMP-3 from both cells in a dose-dependent manner (0.32-1.28 microM). This suppression was accompanied by a decrease in steady-state levels of their mRNAs. These results indicate for the first time that UTI down-regulates the production of proMMP-1 and proMMP-3 accompanying with the decrease in the expression of their mRNAs, and therefore UTI actually participates in the maintenance of fetal membranes and/or uterine cervix by overall suppression of MMP production along with the known inhibitory actions towards serine proteinases.

Blotting, Northern↗