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Biomedical subjects

H Tsuji

Publications and source records attributed to H Tsuji.

At least 145 records · Page 8Linked to original sources

All-trans retinoic acid regulates adhesion mechanism and transmigration of the acute promyelocytic leukaemia cell line NB-4 under physiologic flow.

The success of all-trans retinoic acid (ATRA) in the therapy of acute promyelocytic leukaemia (APL) has received increased attention. Unfortunately, life-threatening multiorgan failure commonly occurs, i.e. retinoic acid syndrome, and is thought to be the result of organ infiltration by leukaemic cells. We hypothesized that ATRA-induced differentiation of APL cells leads to adhesion receptor alterations responsible for leucocyte extravasation from the blood into tissue. Changes in adhesive properties of the APL cell line NB-4 in response to ATRA were investigated using a parallel plate flow chamber under conditions that recapitulate physiologic flow conditions. Untreated NB-4 cells initially tether and roll on activated human umbilical vein endothelial cell monolayers using a combination of E-selectin, P-selectin and alpha4 integrin. After ATRA treatment, > 80% of initial NB-4 cell attachment to endothelial cells was E-selectin dependent. Stable arrest (firm adherence) of NB-4 cells on activated endothelium was also altered by ATRA treatment. Untreated NB-4 cells used alpha4 integrin to arrest on endothelium, but beta2 integrin dependent arrest was induced by ATRA. With the acquisition of beta2 integrin function, ATRA-treated cells acquired the ability to transmigrate through activated endothelium. Thus, ATRA dramatically altered the adhesion phenotype on NB-4 cells: ATRA induced rolling largely attributable to E-selectin, abrogated alpha4 integrin dependent rolling, and promoted acquisition of beta2 integrin dependent firm adherence and transmigration. These findings represent novel cellular and differentiation effects of ATRA, and, to our knowledge, are the first demonstration that a therapeutic agent differentially regulates alpha4 and beta2 integrin on the same leucocyte.

Cell Adhesion↗

Detection of two novel mutations (nt2762, exon 2, CAG to TAG, and nt2483 or 2484, exon 2, +A) in individuals with congenital type I antithrombin deficiencies.

Genetic analyses were performed on two Japanese kindreds with congenital type I antithrombin deficiency causing recurrent thrombosis. The seven exons and flanking intron regions of the antithrombin gene were amplified by polymerase chain reaction followed by direct nucleotide sequencing. In case 1, one novel nonsense mutation, CAG to TAG at codon 100, nucleotide 2762, in exon 2, was detected. In case 2, one novel minor insertion, AT to AAT at codon 7, nucleotide 2483 or 2484, in exon 2, was detected, leading to a frameshift which resulted in a stop codon TGA at codon 32.

Adolescent↗

Interleukin-1alpha stimulated prostacyclin release by increasing gene transcription of prostaglandin H synthase and phospholipase A2 in human vascular endothelial cells.

This study was conducted to evaluate the effects of interleukin-1alpha (IL-1alpha) on prostacyclin (PGI2) production in cultured human vascular endothelial cells in association with intracellular Ca2+, inositol 1,4,5-trisphosphate (IP3), and with prostaglandin H synthase (PGHS) and phospholipase A2 (PLA2) gene expression by using the competitive polymerase chain reaction (PCR) method. IL-1alpha did not increase PGI2 production for 15 min, but induced an increase of about three-fold relative to that in controls at 60 and 180 min. IL- 1alpha had no effect on intracellular Ca2+ levels throughout the experimental period. In this study, consistent with previous reports, PGHS-1 messenger RNA (mRNA) was constitutively expressed, whereas PLA2 mRNA was not. After stimulation with IL-1alpha, PLA2 mRNA level showed an eightfold increase within 15 min, and PGHS-2 mRNA level increased by 76-fold within 180 min. PGHS-1 mRNA level was increased 1.6-fold at 180 min. These results suggest the existence of regulatory mechanisms of IL-1alpha-induced PGI2 production, which involve PGHS and PLA2 gene transcription.

Base Sequence↗

Experience with the rectus abdominis myocutaneous flap with vascularized hard tissue for immediate orbitofacial reconstruction.

For a considerable tissue defect of the orbitofacial region after skull base or head and neck tumor en bloc extirpation, we have developed the "flying buttress" technique using the vascularized hard tissue rather than the multi-stage operative method using bone graft or alloplastic materials. The procedure reconstructs the inferior orbital rim and the zygomatic prominence--flying buttresses bridging transversely in a missing face--with free flap coverage, simultaneously in the primary surgery so that the bony structure is maintained for years and ptosis of a large flap is minimized. We prefer to use the rectus abdominis myocutaneous flap for tissue restoration and two types of vascularized hard tissue: the costal cartilages combined with the flap and the temporalis muscle-pedicled calvarial bone. Representative cases are illustrated and the technique is detailed.

Adolescent↗

Prostatic cancer with huge cystic degeneration.

This report details a case of prostatic cancer associated with cystic degeneration. A cystic mass may occur in the pelvis for various reasons. A congenital cyst is associated with an abnormality in the paramesonephric (müllerian) duct or mesonephric (wolffian) duct. An acquired cyst can be classified into three main types, retention, malignant and parasitic, however a cyst accompanying prostatic cancer is rare. In this particular case the size of the cyst under imaging was approximately 15 cm in diameter; this makes it one of the largest among those previously reported.

Aged↗

Enhanced surfaces for endothelial cell seeding.

Silver negative ions (Ag-) were implanted to polystyrene (PS) and tissue culture polystyrene (TCPS) by using neutral and ionized alkaline bombardment-type heavy negative ion sources, NIABNIS. Surface property and biocompatibility of Ag(-)-implanted TCPS and PS were investigated. Enhanced growth of vascular endothelial cells was observed on Ag(-)-implanted TCPS at a dose of 10(16) ions.cm-2 at an ion energy of 10 keV and Ag(-)-implanted (at ca. 10(15) ions.cm-2 dose and 10 keV energy) PS region. As a result of Ag(-)-implantation, PS and TCPS surfaces were considered to be more hydrophobic and to be more hydrophilic, respectively.

Biocompatible Materials↗

Effect of dietary seal and fish oils on triacylglycerol metabolism in rats.

Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids were distributed mainly in the sn-1 and 3 positions of seal oil triacylglycerol and in the sn-2 position of fish oil triacylglycerol. Seal oil or fish oil-rich fats having constant polyunsaturated/monounsaturated/saturated fatty acids and n-6/n-3 polyunsaturated fatty acid (PUFA) ratios were fed to rats for 3 wk. Control rats were fed on a fat containing linoleic acid as the sole PUFA. Seal oil more effectively lowered serum and liver triacylglycerol concentrations than fish oil. The activities of fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase (G6PDH) and hepatic triacylglycerol lipase (HTGL) were significantly lower in the seal oil group than in the control group, whereas the activity of HTGL was significantly lower and the hepatic peroxisomal beta-oxidation and activity of lipoprotein lipase (LPL) in adipose tissue were significantly higher in the fish oil group than in the control group. These observations suggest that the predominant hypotriacylglycerolemic effect of seal oil is caused by the suppression of fatty acid synthesis.

Adipose Tissue↗

Immunochemical characterization of ovomucoid from Japanese quail egg white using monoclonal antibodies.

The ovomucoid of Japanese quail egg white is known as a proteinase inhibitor or protein component responsible for egg allergy. In order to characterize the antigenic properties of ovomucoid in relation to its molecular structure, we have prepared two monoclonal antibodies, E9 (IgG1) and E11 (IgG1), recognizing distinct epitopes from each other. These monoclonal antibodies bound to the SDS/mercaptoethanol-treated ovomucoid, but not to the reductively carboxymethylated and pyridylethylated ovomucoid. By immunoblotting analysis of the peptic digests of ovomucoid, it was shown that E9 bound to the fragment consisting of two domains, I and II, of the ovomucoid, and that E11 reacted with the fragment containing domain III. These results indicate that the antigenic activity depends on the conformational structure of domains tightly folded by disulfide linkages. Ovomucoids from hen and duck were also recognized by both the antibodies, although having less affinity compared to the one from Japanese quail. These antibodies proved to be effective in establishing an enzyme-linked immunosorbent assay system for quantitative analysis of quail ovomucoid.

Amino Acid Sequence↗

[Serum immunoglobulin concentrations and autoantibodies in patients with Yusho].

To evaluate chronic immune effects of polychlorinated biphenyl (PCB), serum immunoglobulin concentrations and autoantibodies were studied in 79 patients with Yusho in 1997. Serum levels of immunoglobulin A (IgA), immunoglobulin G (IgG) and immunoglobulin M (IgM) were elevated in 10 cases (12.7%), 19 cases (24.1%) and 7 cases (8.9%), respectively. Autoatibodies were present in some patients of Yusho; 10 cases (12.7%) for rheumatoid factor and 36 cases (45.6%) for antinuclear antibody. LE factor was not detected. There were no significant correlations between blood PCB concentrations and serum immunoglobulin concentrations, or presence of autoantibodies. We conclude that antinuclear antibody in patients with Yusho is frequent, although it may not be associated with blood PCB concentration.

Adult↗

[The regulation of blood coagulation and fibrinolysis by vascular endothelial cells].

Vascular endothelial cells play a critical role in the regulation of coagulation and fibrinolysis by controlling the expression of tissue factor (TF), tissue factor pathway inhibitor (TFPI), plasminogen activator inhibitor-1 (PAI-1), and tissue type plasminogen activator (TPA). Vasoconstrictors can induce TF and PAI-1 expression without changing the TFPI or TPA expression level. Vasodilators can not alter that of TFPI or TPA, but they inhibit the induction of TF or PAI-1 by vasoconstrictors. These results suggest that by making TF predominant to TFPI and PAI-1 to TPA, vasoconstrictors cause the vascular endothelial cells to become thrombogenic and vasodilators inhibit this process. The thrombogenicity by vasoconstrictors may be originally involved in the protective mechanisms against bleeding, and antithrombogenicity by vasodilators may be originally a part of the protective mechanisms against stasis. In treating hypertension, it is necessary to consider this thrombogenicity by vasoconstrictors in order to avoid iatrogenic thrombotic disease.

Blood Coagulation↗

[Invasive amebiasis at an institution for the mentally retarded in Hyogo Prefecture].

An outbreak of amebiasis caused by Entamoeba histolytica occurred at an institution for mentally retarded persons in Hyogo Prefecture. Twelve out of a total of 49 admitted persons exhibited E. histolytica cysts in their stool, and 13 including persons in whom no cysts had been detected showed positive serological reactions for E. histolytica infection. However, neither the cyst nor the antibody against the organism was detected in the staff members of the institution. Indirect fluorescence antibody test and sandwich enzyme-linked immunosorbent assay with a monoclonal antibody specific for pathogenic strains of E. histolytica revealed that all trophozoite strains grown from cysts in stool samples from five patients were pathogenic. Epidemiological analysis strongly suggested that a patient in the institution had been infected with an organism from a patient outside the institution, and that infection may have spread among the admitted persons due to abnormal behavior. Administration of metronidazole resulted in effective elimination of the cysts from the stool of the cyst-carriers.

Adult↗

Heart rate variability and left ventricular dilatation early after myocardial infarction.

To assess clinically whether alterations of autonomic tone precede left ventricular dilatation, heart rate variability and early left ventricular dilatation after a first myocardial infarction were assessed. Low-frequency power (LF), high-frequency power (HF), and total power (TP) were obtained by ambulatory electrocardiogram on day 1 in 53 patients with a first acute myocardial infarction. Left ventricular end-diastolic volume determined by echocardiography was obtained on day 1 and day 14. Stepwise linear regression analysis was used to assess the associations of early left ventricular dilatation with heart rate variability adjusted for clinical variables. Higher LF and TP were significantly associated with early left ventricular dilatation after adjustment for age, sex, site of myocardial infarction, acute revasucularization, peak creatine kinase level, history of hypertension, and use of angiotensin-converting enzyme inhibitors and beta-blockers. Higher LF and TP preceded early left ventricular dilatation after myocardial infarction.

Echocardiography↗

Hepatocellular carcinoma with metastasis to the rib complicated by hemothorax. An autopsy case.

A 64-year old man was admitted to our hospital with multiple hepatocellular carcinoma (HCC) lesions in the liver, lung and bone. Three weeks after admission, the patient became complicated with right upper chest pain. A chest radiograph showed a marked increase in right pleural effusion. Thoracentesis demonstrated a hemothorax. Despite treatment with a continuous pleural tap and blood transfusions, the patient's clinical status worsened and he developed severe dyspnea. His right pleural effusion might be considered to be caused by a rupture of the HCC metastasis in the right 2nd rib. The patient died due to respiratory and hepatic failure 26 hours after his occurring the pleural effusion. An autopsy revealed moderately differentiated HCC in the liver, lung and bone. The HCC metastasis of the right 2nd rib was found to have torn the nearby pleura. We described a rare case in which hemothorax was caused by a ruptured rib-based HCC.

Bone Neoplasms↗

Attenuated liver fibrosis and depressed serum albumin levels in carbon tetrachloride-treated IL-6-deficient mice.

Chronic intermittent injection of carbon tetrachloride (CCl4) for more than 10 weeks induced liver fibrosis in mice, as evidenced by positive Azan staining and increased intrahepatic collagen content. Preceding the onset of liver fibrosis, interleukin-6 (IL-6) gene expression was enhanced in liver and immunoreactive IL-6 was detected in infiltrating inflammatory cells. To delineate the role of IL-6 in this process, we treated IL-6-deficient mice with CCl4 in a similar manner for 12 weeks, after which fibrotic changes were less evident and serum albumin levels were lower in IL-6-deficient than wild-type mice. Moreover, CCl4-induced expression of transforming growth factor beta1 and hepatocyte growth factor genes in liver was significantly reduced in IL-6-deficient mice. Thus, IL-6 may be vitally involved in fibrotic changes and maintenance of serum albumin levels, partly by modulating intrahepatic expression of these cytokines.

Animals↗