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Y Horie

Publications and source records attributed to Y Horie.

At least 145 records · Page 8Linked to original sources
PubMed1994

Induction of HLA-DR antigen expression on human colonic epithelium by tumor necrosis factor-alpha and interferon-gamma.

BACKGROUND: We investigated the effects of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) on HLA-DR expression on human normal colonic epithelium, using an organ culture technique. METHODS: Biopsy specimens from normal colonic mucosa were cultured for 24 h with various concentrations of TNF-alpha and/or IFN-gamma. Epithelial HLA-DR antigens were identified by an indirect immunoperoxidase staining method. RESULTS: No expression of epithelial HLA-DR antigens was observed in specimens cultured with medium alone. Concentrations of 10(3) U/ml or higher of TNF-alpha and 10(2) U/ml or higher of IFN-gamma induced expression of HLA-DR antigens in a dose-dependent manner. Expression of HLA-DR was increased in specimens cultured with both TNF-alpha and IFN-gamma compared with those cultured with either cytokine alone. CONCLUSIONS: Our findings suggest that both TNF-alpha and IFN-gamma play important roles in regulating the expression of HLA-DR on colonic epithelium in patients with inflammatory bowel disease.

Aged↗
PubMed1994

Altered lipoprotein metabolism in transgenic mice expressing low levels of a human receptor-binding-defective apolipoprotein E variant.

Transgenic mouse lines were produced that expressed low levels of a receptor-binding-defective variant of human apolipoprotein (apo) E, apoE(Arg112, Cys142). In transgenic mice, the human apoE was produced only by the kidney, whereas endogenous mouse apoE was produced mainly by the liver. The plasma concentration of the transgenic protein was about half that of endogenous apoE. The expression of transgenic apoE did not affect total plasma cholesterol and triglyceride levels, but the distribution of the human variant differed from that of endogenous apoE in the intermediate size and density range, where the transgenic protein accumulated selectively. Immunoblots of agarose gels of lipoprotein fractions showed that the transgenic protein occurred primarily on large alpha-migrating particles (HDL1). This phenomenon was not observed in transgenic mice expressing normal human apoE-3, which distributed like endogenous apoE, suggesting that the defective apoE variant perturbed HDL1 metabolism. In mice fed a high-fat, high-cholesterol diet, the transgenic apoE associated primarily with the apoB-containing lipoproteins. A significantly higher increase in very low density lipoprotein cholesterol was observed in fat-fed transgenics compared to fat-fed nontransgenic mice, suggesting a metabolic perturbation of apoB-containing lipoproteins. Thus, the receptor-binding-defective variant, apoE(Arg112, Cys142), expressed at low levels by the kidney, alters lipoprotein metabolism in transgenic mice, presumably by interfering with apoE-mediated removal of the lipoproteins from circulation.

Animals↗
PubMed1994

[Clinical significance of serum and urinary neopterins after transcatheter arterial embolization for hepatocellular carcinoma].

To elucidate the immunological effects of transcatheter arterial embolization (TAE) for hepatocellular carcinoma (HCC), serum and urinary neopterins were measured using the radioimmunoassay in patients with HCC before and after TAE (n = 11), and compared with one shot arterial injection (AI)(n = 8). At the third day after TAE, serum and urinary neopterin levels were maximally elevated up to 164% and 158% from their respective baselines (p < 0.01). By contrast, these levels were unaffected after AI. In considering the changes of natural killer cell activity, C-reactive protein, transaminase and alpha-fetoprotein, these results suggest that the determination of neopterin levels after TAE may be not only valuable to assess the necrotic effect of TAE, but also be useful for evaluating cellular immunity after TAE.

Adult↗
PubMed1994

Combination therapy with transcatheter arterial embolization and percutaneous ethanol injection for advanced hepatocellular carcinoma.

The effectiveness of transcatheter arterial embolization (TAE) combined with percutaneous ethanol injection (PEI) was investigated in 18 patients with advanced hepatocellular carcinoma (HCC), and compared with 18 patients with HCC treated by TAE therapy alone. In both groups, patients had multiple lesions or a single lesion larger than 3 cm. The pretreatment characteristics of the patients in the two groups showed that serum bilirubin in the TAE-PEI group was significantly higher than that in the TAE-only group, but that the patients in the two groups were comparable in all other respects. The cumulative survival rate of the TAE-PEI group estimated by the Kaplan-Meier method was 100% for 10 months, 82% for 20 months, 53% for 30 months and 18% for 40 months, whereas that of the TAE-only group was 75% for 10 months, 50% for 20 months, 30% for 30 months and 30% for 40 months. The survival rate in the TAE-PEI group was significantly higher than that in the TAE group. Moreover, the survival rate of patients whose main tumor was 4 cm or larger, was significantly higher in the TAE-PEI group than that in the TAE-only group. The average survival period of these patients in the TAE-PEI group was five times as long as that in the TAE-only group. The survival rate of Child's B and C patients in the TAE-PEI group was significantly higher than that in the TAE-only group.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Expression of gamma-glutamyl transpeptidase mRNA after depletion of glutathione in rat liver.

Gamma-glutamyl transpeptidase (gamma-GT) is the enzyme in the gamma-glutamyl cycle which mediates the first step of glutathione degradation. Recently, it has been reported that diethyl maleate, a glutathione-depleting agent, enhanced hepatic gamma-GT activity. In this study, we examined how gamma-GT mRNA was expressed after the depletion of glutathione by using the RT-PCR method and in situ hybridization technique with digoxigenin-labeled oligonucleotide probe. We could detect hepatic gamma-GT mRNA in the epithelial cell of bile duct and the cytoplasm of hepatocytes in the periportal area, even in control rats. Furthermore, we found that the expression of gamma-GT mRNA was expanded to hepatocytes of a whole lobule 12 hr after depletion of glutathione by diethyl maleate, followed by the return to the pretreatment condition under which gamma-GT mRNA appears to be controlled in correlation with hepatic glutathione levels. These results suggest that the depletion of glutathione may induce hepatic gamma-GT activity through an increased synthesis of its mRNA.

Animals↗
PubMed1993

Ca2+ entry pathways activated by the tumor promoter thapsigargin in human platelets.

Thapsigargin-activated Ca2+ entry into platelets was examined in the presence of S-145, a thromboxane A2 receptor antagonist, to inhibit indirect effects by endogenously formed prostaglandin H2/thromboxane A2. With external Ca2+ present, 0.2 microM thapsigargin caused a prompt increase in intracellular Ca2+ concentration ([Ca2+]i) followed by a gradual increase. Pretreatment with 6 microM wortmannin, a specific inhibitor of myosin light chain kinase, partly inhibited the increase in [Ca2+]i. In Ca(2+)-free EGTA buffer, thapsigargin induced a smaller increase in [Ca2+]i, and subsequent addition of Ca2+ to the buffer caused a further prompt increase in [Ca2+]i, demonstrating external Ca2+ entry. Wortmannin only partly inhibited this entry of external Ca2+. The wortmannin-insensitive Ca2+ entry pathway remained open for more than 6 min in Ca(2+)-free buffer. On the other hand, when receptor agonists such as thrombin and U46619 were substituted for thapsigargin, activation of the wortmannin-insensitive Ca2+ entry was transient (Hashimoto et al., J. Biol. Chem (1992) 267, 17078-17081). In the presence of S-145 and wortmannin, thapsigargin stimulated phosphorylation of neither the 20-kDa myosin light chain nor the 47-kDa protein, a substrate of protein kinase C. These results suggest that thapsigargin induces external Ca2+ entry by two mechanisms: (1) a mechanism involving myosin light chain kinase; (2) a mechanism, not activated by receptor agonists, that is independent of the major protein kinases of platelets.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1993

Spindle cell hemangioendothelioma: a report of two cases.

Two cases of spindle cell hemangioendothelioma (SCH) are reported. One of the patients was a 16 year old Japanese female, who had been suffering from Ollier's disease (multiple enchondromatosis) since 3 years of age and had developed multiple SCH in the right leg at the age of 11 years. Spindle cell hemangioendothelioma lesions coincided with the site of enchondromatosis and increased in number thereafter. This is the first report of Ollier's disease complicated with multiple SCH. Another patient, a 33 year old Japanese female, who was a carrier of hepatitis B virus (HBV), developed solitary SCH in the lateral aspect of the right ankle where a lipoma was extirpated 10 years previously. Tumor cells of both cases were composed of four cell types: (i) spindle cells; (ii) epithelioid cells; (iii) vacuolated endothelial cells; and (iv) usual endothelial cells. Endothelia in the cavernous area and vacuolated cells reacted to Ulex europaeus agglutin 1 (UEA-I), factor VIII-related antigen and vimentin. Spindle cells and epithelioid cells reacted only to vimentin.

Adolescent↗
PubMed1993

A modified method of mixed lymphocyte reaction: establishment of the assay system and its application to extracts of fungal cultures.

A modified mixed lymphocyte reaction (MLR) assay was developed to screen immunosuppressive agents. In the MLR, irradiation of splenocytes with UV light was employed for the preparation of stimulator cells, and the highest response was observed with the combination of splenocytes of C3H/He mice as a stimulator and those of C57BL/6 as a responder. The blastogenesis of the responder cells was quantified by a colorimetric method using MTT in 96-well microculture plates. For screening immunosuppressive substances, the MLR in combination with a cytotoxicity test can distinguish immunosuppressors from cytotoxic agents. The applications of this assay system to extracts of fungal culture was also described.

Animals↗
PubMed1993

[Anesthetic management of a patient with pemphigoid for prosthetic replacement after femoral neck fracture].

We report an 83 year-old male with pemphigoid who underwent replacement of a femoral neck prosthesis following femoral neck fracture. Problems associated with anesthetic management of patients with vesiculobullous diseases such as pemphigoid include fluid, electrolyte and protein loss, and secondary infection because of the fragility of the skin and mucous membranes. Avoidance of trauma to the skin and mucous membranes is therefore important. Intubation of the trachea may be hazardous because of the possibility of airway obstruction resulting from oropharyngeal and laryngeal bullae. The patient was successfully anesthetized with spinal anesthesia using 2.5 ml of tetracaine in a 0.4% solution of 0.45% NaCl. An evacutable mattress was used to protect the patient from pressure points in the lateral position, and to minimize the hazards from pressure by spreading the weight. Surgery proceeded uneventfully and the postoperative period was uncomplicated.

Aged↗
PubMed1993

Preferential association of apolipoprotein E Leiden with very low density lipoproteins of human plasma.

Apolipoprotein (apo) E Leiden is a rare variant of human apoE characterized by defective receptor binding and associated with dominant transmission of type III hyperlipoproteinemia. In heterozygotes, apoE Leiden is present in higher concentrations in both total plasma and very low density lipoproteins (VLDL) than the other apoE allele product. In the present study we analyzed cell expression and plasma lipoprotein association of apoE Leiden to determine whether the unequal concentration of the two apoE allele products could be explained by differences in secretion rate from the hepatocyte or by preferential association with VLDL. We transfected the rat hepatoma cell line McA-RH7777 with apoE Leiden or normal human apoE3, and studied their secretion and media distribution. In pulse-chase experiments, the secretion of apoE Leiden was comparable to that of both human apoE3 and rat endogenous apoE, approaching 100% in 90 min. In similar transfection experiments, secreted apoE Leiden was significantly less glycosylated than normal apoE3 (21.7% vs. 36.6%, P < 0.005, n = 4), a finding also noted for apoE Leiden in human plasma. In in vitro incubation experiments, apoE Leiden showed a markedly higher preference for VLDL of normolipidemic human plasma when compared to both apoE3 (2.6-fold, P < 0.001) and apoE4 (1.6-fold, P < 0.001). These results suggest that the accumulation of apoE Leiden in VLDL derives from a high affinity of the mutant protein for the VLDL. This enrichment in defective apoE probably exacerbates impairment of VLDL removal from the circulation, thus contributing to the dominant transmission of type III hyperlipoproteinemia.

Animals↗
PubMed1992

The functional characteristics of a human apolipoprotein E variant (cysteine at residue 142) may explain its association with dominant expression of type III hyperlipoproteinemia.

Type III hyperlipoproteinemia typically is associated with homozygosity for apolipoprotein (apo) E2(Arg158----Cys). Dominant expression of type III hyperlipoproteinemia associated with apoE phenotype E3/3 is caused by heterozygosity for a human apoE variant, apoE3(Cys112----Arg, Arg142----Cys). However, this apoE3 variant was not separable from the normal apoE3 in these patients' plasma because the two proteins have identical amino acid composition, charge, and molecular weight. Therefore, to determine the functional characteristics of this protein, we used recombinant DNA techniques to produce this apoE variant in bacteria. We also produced a non-naturally occurring variant, apoE(Arg142----Cys), that had only the cysteine substituted at residue 142. These two apoE variants were purified from cell lysates of the transfected Escherichia coli by ultracentrifugal flotation in the presence of phospholipid, by gel filtration chromatography, and by heparin-Sepharose chromatography. Both Cys142 apoE variants bound to lipoprotein receptors on human fibroblasts with only about 20% of normal binding activity. Therefore, cysteine at residue 142, not arginine at residue 112, is responsible for the decreased receptor binding activity of the variants. Cysteamine treatment and removal of the carboxyl-terminal domain had little effect on the binding activity, whereas both modulate the receptor binding activity of apoE2(Arg158----Cys). The mutation at residue 142 decreased the binding activity of apoE to both heparin and the monoclonal antibody 1D7 (this antibody inhibits receptor binding of apoE), whereas apoE2(Arg158----Cys), which is associated with recessive expression of type III hyperlipoproteinemia, binds normally to both. The Arg112, Cys142 variant predominantes 3:1 over normal apoE3 in the very low density lipoproteins of plasma from an affected subject, as assessed by differential reactivity with the antibody 1D7. The unique combination of functional properties of the Arg112, Cys142 variant provides a possible explanation for its association with dominant expression of type III hyperlipoproteinemia.

Amino Acid Sequence↗
PubMed1992

Genotoxicity of fungi evaluated by SOS microplate assay.

By an introduction of sodium dodecylsulfate for cell lysis and immunomicroplate for mass assay, the modified SOS microplate assay method was established and applied for the evaluation of genotoxicity of mycotoxins and fungal cultures. Among 20 mycotoxins, the carcinogenic dihydrobisfuranoids such as aflatoxin B1, sterigmatocystin, and versicolorin A were positive in the presence of the activation system. While, the carcinogenic anthraquinones and lactones such as luteoskyrin, rugulosin, ochratoxin A, patulin, and citrinin were negative. The survey on genotoxic fungi revealed that, among 15 fungal isolates Aspergillus versicolor, Emericella acristata, and others were positive. Additional survey on 265 fungal isolates have revealed that various Aspergillus genera such as A. flavus, A. parasiticus, A. ustus, A. nidulans, and others were positive for SOS induction, along with several isolates of Fusarium moniliforme. The chemical analysis revealed that the dihydrobisfuranoids such as aflatoxin B1, and sterigmatocystin were the major genotoxic metabolites of several Aspergillus species. The SOS microplate assay system is a simple and rapid procedure for the mass screening of genotoxic fungi, particularly of the dihydrobisfuranoids-producing strains.

Animals↗