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Biomedical subjects

S Taniguchi

Publications and source records attributed to S Taniguchi.

At least 343 records · Page 19Linked to original sources

Malignant schwannoma in a case of type 1 neurofibromatosis with decreased immunoreactivity of smooth muscle alpha-actin in tumor vessels.

A malignant schwannoma in the left calf of a 37-year-old man with type 1 neurofibromatosis is herein reported. Since it is known that capillaries in benign neurofibromas are accompanied by hypertrophic pericytes expressing an abundant amount of smooth muscle alpha-actin (SMAA), we examined the immunohistochemical reactivity of SMAA within this malignant tumor and then compared it with that in surrounding benign areas. In the nests of malignant cells, decreased SMAA staining was found in the capillary walls. In the benign tissues around the malignant tumor, various extents of SMAA could be visualized in the vessels and myofibroblasts. Platelet-derived growth factor (PDGF) was also detected in the tumor, suggesting that cytokines secreted by malignant cells may have an influence on the expression of SMAA as well as on the alteration of the structure of blood vessels.

Actins↗

Expression of type II transforming growth factor-beta receptor mRNA in human skin, as revealed by in situ hybridization.

We studied the expression of the type II transforming growth factor-beta receptor mRNA in normal and psoriatic human skin in vivo. In situ hybridization analysis showed that its signals were expressed in the epidermal keratinocytes of the basal, the spinous and the granular layer, although no significant signals were observed in the fibroblasts or endothelial cells of the dermis. The follicular epithelium also expressed the type II transforming growth factor-beta receptor mRNA. There was no difference in the pattern of DNA expression between normal and psoriatic skin. These results suggest that the mRNA of the type II transforming growth factor-beta receptor is mainly expressed in the epithelial components of skin and controls the proliferation of the epidermis.

Endothelium↗

Expression of the fos oncogene in basal cell carcinoma.

Using immunohistochemical technique and Western blot analysis, we demonstrated the increased expression of the c-fos oncogene in the infiltrative type of solid basal cell carcinoma (BCC), but low or no expression in the circumscribed type of solid BCC. The infiltrative type is called aggressive BCC and had been shown to exhibit a higher rate of recurrence than the circumscribed type. Our results indicate that increased expression of the fos oncogene is closely related to the invasive ability of the tumor cells.

Blotting, Western↗

Haemopoietic spleen colony formation in the rat: effect of 89Sr-induced bone marrow aplasia.

Regulation of spleen-colony formation, a clonal assay for haemopoietic stem cells, is very different in mice and rats. In the rat, there is an involution of the colony-forming ability of the spleen during infantile development, whereas in mice the ability is maintained throughout life. In our re-evaluation of endogenous spleen colony formation in rats after graded doses of total-body irradiation, colonies ceased to appear after 12 weeks of age. However, histological sections showed that there were tiny colonies growing in the spleen, even at 20 weeks. These microscopical colonies developed into visible colonies when the rats were given treatments that increased the haemopoietic requirement. Thus, the amount of 59FeCl3 incorporated into the spleen increased to compensate for a decrease in uptake by the bone marrow. Rats in which bone-marrow activity was inhibited by 89SrCl2, showed extensive colony formation in the spleen, even after 12 weeks of age, when the endogenous colonies were induced by a sublethal dose of radiation. About twice as much 59Fe acetate activity was incorporated into the spleens of the experimental animals than in those of control rats. These findings imply that spleen-colony formation responds to the haemopoietic requirement of the spleen rather than that of the bone marrow. Furthermore, the requirement of the spleen seems to be much smaller in rats than in mice, because bone-marrow capacity for haemopoiesis is relatively larger in rats.

Aging↗

Cutaneous metastases of pancreatic carcinoma with unusual clinical features.

Cutaneous metastases from pancreatic carcinoma are uncommon. Eight cases have been described in the literature. The metastases display some common features such as umbilical nodules and the histologic pattern of adenocarcinoma. Our patient had erythematous infiltrated plaques in the left axilla and on the upper portion of the chest. A skin biopsy specimen disclosed many poorly differentiated atypical cells throughout the dermis. The diagnosis was confirmed by positive immunohistochemical staining for carbohydrate antigen 19-9.

Adenocarcinoma↗

Different sensitivities of the murine melanomas BL-6 and BL-6-beta m to local injections of interleukin-2 (IL-2). Analysis of gangliosides after the treatment.

The murine melanoma cell line BL-6-beta m, which is a stable cell line transfected with a gene coding a unique actin subspecies called beta m to the BL-6 cell line, has low metastatic potentials as compared with those of the parent cell line. BL-6-beta m melanomas were found to be sensitive to in vivo local injection of IL-2, while BL-6 melanomas showed almost no response. Ganglioside analysis of BL-6 and BL-6-beta melanomas revealed that the main ganglioside of both melanomas was GM3, which suggested that different sensitivities between BL-6 and BL-6-beta m melanomas to the injection of IL-2 did not relate to the different compositions of main gangliosides. However, minor components of the gangliosides such as GM2 and GM1 emerged only in BL-6-beta m melanomas after treatment with IL-2. Local injection of IL-2 caused considerable infiltration of anti-asialo GM1-positive cells into the nests as well as the interstitials of BL-6-beta m melanomas. In contrast, in the BL-6 melanomas treated with IL-2, infiltration of the anti-asialo GM1-positive cells was hardly seen, although anti-Thy1,2 and anti-macrophage-positive cells were found to more or less the same extent as observed in BL-6-beta m melanomas. These results suggest that the murine metastatic variant melanoma cell lines BL-6 and BL-6-beta m have different properties in terms of sensitivity to in vivo IL-2 treatment, and a slight enhancement of the ganglioside components GM2 and GM1 expression only in BL-6-beta m after IL-2 treatment may play a role in the IL-2-mediated attraction of immune cells or may explain the different sensitivities of the two lines to treatment with IL-2.

Actins↗

Intracellular localization and biochemical function of variant beta-actin, which inhibits metastasis of B16 melanoma.

We analyzed the biochemical nature of beta m-actin protein found in mouse B16 melanoma. When we carried out immunostaining with the antibody specific to beta m-actin, filamentous immunofluorescence was observed in B16-F1, a low-metastatic cell line expressing beta m-actin, but not in highly metastatic B16-F10 that did not express beta m-actin. When a purified actin fraction containing beta m-actin was polymerized and immunoprecipitated with anti-beta m-actin antibody, the immunoprecipitate contained beta m-, beta- and gamma-actin. This indicated that the beta m-actin was incorporated into an actin filament together with beta- and gamma-actin in vitro, and this phenomenon was consistently suggested by cellular double immunostaining with anti-beta m-actin and common anti-actin antibody. When the actin fraction containing beta m-actin under a regular depolymerizing condition was subjected to immuno-adsorption assay using anti-beta m antibody and protein-A Sepharose, the immunoadsorbed aggregates contained beta m-, beta- and gamma-actin. This indicates that the actin fraction was not completely depolymerized and contained beta m-actin-containing oligomers, which were too small to be precipitated with anti-beta m-actin antibody alone. The incomplete depolymerization of the beta m-actin-containing fraction was also suggested by the much lower DNase 1 inhibition activity of the beta m-actin-containing fraction than that of beta- and gamma-actin fraction. Furthermore, a DNase 1 binding assay showed that cytoplasmic supernatant prepared from B16-F1 under a low-ionic condition contained less monomeric actin than the cytoplasmic preparation from B16-F10. These results suggested that beta m-actin protein in B16 melanoma probably inhibits the dynamic conversion between the monomeric and polymerized forms of actin, leading to a decrease in cell motility and consequently the suppression of invasiveness and metastasis.

Actins↗

Suppression of murine melanoma growth with a combination of microwave hyperthermia and local injection of interleukin 2.

Local microwave hyperthermia in combination with local injections of interleukin 2 (IL-2) was found to exert a remarkable suppressive effect on murine melanoma growth. Both of these therapeutic modalities caused marked tumour infiltration with natural killer cells. After microwave hyperthermia or IL-2 injection alone there was minimal T-cell infiltration, but T cells were more in evidence following combination therapy.

Animals↗

Cytomegalovirus (CMV) antigenaemia for rapid diagnosis and monitoring of CMV-associated disease after bone marrow transplantation.

A technique for the rapid detection of cytomegalovirus (CMV) antigen-positive blood leucocytes (CMV antigenaemia) was evaluated in 15 marrow transplant patients as a means of diagnosis and for monitoring CMV-associated disease. CMV antigenaemia was determined by direct immunoperoxidase staining of leucocytes with a peroxidase-labelled monoclonal antibody, HRP-C7, which binds an immediate-early antigen of human CMV. CMV antigenaemia occurred in 7/15 marrow transplant patients (47%) and was initially detected between 4 and 6 weeks after transplantation. CMV-associated diseases developed in 3/15 patients (20%). All patients with CMV-associated disease had a relatively large number of CMV antigen-positive leucocytes, exceeding 10 per 50,000 white blood cells (WBCs). In the remaining 12 patients, CMV antigen-positive leucocytes were less than 10 per 50,000 WBCs or were undetectable. CMV-associated disease did not develop in these patients during the period of monitoring. CMV antigen-positive leucocytes were detected more frequently in patients who developed acute graft-versus-host disease (GVHD) or haemorrhagic cystitis than in those without such complications. CMV antigens were detectable from 1 to 4 weeks before the onset of CMV-associated disease which allowed initiation of ganciclovir treatment at an early stage. The degree of CMV antigenaemia paralleled the clinical symptoms and signs, higher degrees of antigenaemia being associated with more significant disease. Thus, the detection of CMV antigen-positive blood leucocytes is useful for the diagnosis and monitoring of CMV-associated disease following bone marrow transplantation.

Acute Disease↗

Treatment of linear localized scleroderma with the anti-allergic drug, tranilast.

A 14-year-old boy with linear localized scleroderma had a dramatic improvement in contractures after treatment with N-(3',4'-dimethoxycinnamoyl) anthranilic acid (tranilast, Rizaben). The observation that this anti-allergic drug was effective in localized scleroderma lends further support to the concept that mast cells play a role in increased collagen synthesis in this disease.

Adolescent↗

Detection and quantitation of EP3 prostaglandin E2 receptor mRNA along mouse nephron segments by RT-PCR.

mRNA of the EP3 prostaglandin E2 (PGE2) receptor was detected and quantitated in microdissected mouse nephron segments by a modified protocol of reverse transcription-polymerase chain reaction (RT-PCR). At the step of RT, a point mutation was introduced in cDNA, which made a new restriction site for the Mbo I enzyme. PCR was performed using a set of primers on the same exon, and genomic DNA was coamplified with cDNA by these primers. PCR products were treated with Mbo I, and signals from genomic DNA and mRNA were separately detected on gel electrophoresis. The relative amount of mRNA per cell was expressed as a ratio of amount of product from mRNA to that from genomic DNA. EP3 PGE2 receptor mRNA expression was abundant in thick ascending limb of Henle, present to a lesser extent in distal convoluted tubules and collecting ducts, and undetectable in glomeruli, proximal tubules, and descending thin limb. The results support the notion that PGE2 modulates water and solute transport through the EP3 receptor in specific structures of the kidney.

Animals↗

[Effect of mesalazine microgranules on experimental colitis].

Mesalazine microgranules are an ethylcellulose-coated formulation from which mesalazine is released throughout the intestinal tract and are expected to be effective for idiopathic inflammatory bowel disease, ulcerative colitis and Crohn's disease. Mesalazine microgranules were administered orally to investigate the distribution of mesalazine throughout the intestinal tract in rats. Mesalazine microgranules distributed sufficient amounts of mesalazine and its metabolite, N-acetyl-mesalazine, to the intestinal tissues, while pure mesalazine delivered lower amounts of both. In acetic acid-induced colitis in rats, mesalazine microgranules administered orally reduced the damage score significantly (P < 0.05) at a dose of 50 mg/kg as assessed by macroscopic observation and at 100 mg/kg as assessed by histological evaluation. The number of ulcers in carrageenan-induced colitis in guinea pigs was inhibited at doses of 50, 100, 200 mg/kg, p.o. The colonic wet weight of rats in 2,4,6-trinitrobenzenesulfonic acid (TNB)-induced colitis was reduced significantly (P < 0.05) at a dose of 50 mg/kg, p.o. Mesalazine microgranules showed the ability to distribute mesalazine efficiently throughout the intestinal tract and showed effectiveness against acetic acid-, carrageenan- and TNB-induced colitis. These studies strongly suggest that mesalazine microgranules are effective for idiopathic inflammatory bowel disease.

Aminosalicylic Acids↗

[Effect of mesalazine, an agent for the treatment of idiopathic inflammatory bowel disease, on reactive oxygen metabolites and LTB4 formation].

Mesalazine microgranules (Pentasa) were developed as a drug for idiopathic inflammatory bowel diseases such as ulcerative colitis and Crohn's disease. In this study, we examined the effect of mesalazine on radical scavenging, lipid peroxidation and the formation of LTB4. Mesalazine reduced the free radical 1,1-diphenyl-2-picrylhydrazyl with an IC50 value of 9.5 microM. It scavenged hydrogen peroxide and hypochlorite (IC50: 0.7 microM and 37.0 microM, respectively), but had no effect on superoxide. Lipid peroxidation in rat liver microsomes was inhibited by mesalazine (IC50: 12.6 microM). Mesalazine significantly inhibited (P < 0.01) gastric mucosal lipid peroxidation induced by ischemia and reperfusion in rats at a dose of 50 mg/kg, p.o. Mesalazine also inhibited the formation of LTB4 in rat peritoneal neutrophils (IC50: 44.9 microM). N-Acetyl-mesalazine, the metabolite of mesalazine, had no effect on radical scavenging and lipid peroxidation. Only a high concentration (1 mM) of the metabolite inhibited the formation of LTB4. These studies suggest that mesalazine inhibits cell injury in the inflamed mucosa by scavenging reactive oxygen metabolites and prevents the invasion of neutrophils by inhibition of LTB4 formation.

Aminosalicylic Acids↗

Catechol estrogens are more potent antioxidants than estrogens for the Cu(2+)-catalyzed oxidation of low or high density lipoprotein: antioxidative effects of steroids on lipoproteins.

In order to clarify the mechanism of antiatherogenic action of several steroids such as estrogens, dehydroepiandrosterone (DHEA) and dexamethasone, we investigated the effects of various steroids on the copper (Cu2+)-catalyzed oxidation of low density lipoprotein (LDL) or high density lipoprotein (HDL) in 0.15 M NaCl by measuring thiobarbituric acid-reactive substances (TBARS). At a concentration of 10(-5) M, estrogens strongly protected against LDL oxidation by 0.5 microM Cu2+ in the following order of inhibition: estradiol (E2) (75%), estrone (E1) (35%) and estriol (E3) (30%). However, the corresponding metabolites of these estrogens, the catechol estrogens, had an even more protective effect on LDL oxidation by 0.5 microM Cu2+ in the following order of inhibition: 2-hydroxyestradiol (2-OHE2) (98%), 2-OHE1 (97%) and 2-OHE3 (96%). E2 and 2-OHE2 from 10(-7) M to 10(-5) M inhibited LDL oxidation in a dose-dependent manner, with a more marked effect for oxidation by 0.1 microM Cu2+ than by 0.5 microM Cu2+. 10(-5) M dexamethasone produced a slight (10%) but significant inhibition of LDL oxidation by 0.5 microM Cu2+. In addition, the estrogens and catechol estrogens were also effective in protecting against HDL oxidation by 0.5 microM Cu2+. Other steroids including DHEA and DHEA-sulfate had no antioxidative effects on either LDL or HDL in this system. These results indicate that estrogens and their metabolites, the catechol estrogens, exert antioxidative effects on both LDL and HDL. The catechol estrogens may be more important antioxidants than estrogens for both LDL and HDL.(ABSTRACT TRUNCATED AT 250 WORDS)

Antioxidants↗

Unique intronic variations of HLA-DQ beta gene in early-onset periodontitis.

Human leukocyte antigen (HLA) class II beta chain plays an important role in the recognition of foreign antigens in immune reactions. Different forms of immune reaction may be concerned with initiation and progression of infectious diseases such as periodontitis. In this study we examined the frequency of HLA class II serotype and the variation of HLA class II beta gene in periodontitis patients. HLA serotypic frequencies in 70 Japanese patients with periodontitis and 26 individuals with periodontal health were examined. No HLA serotype specific to any type of periodontitis was observed. In order to detect differences among some HLA serotypes, restriction fragment length polymorphism (RFLP) analysis was undertaken with cDNA probes for HLA-DR beta and HLA-DQ beta genes in 20 subjects (15 patients and 5 healthy individuals). Atypical BamHI and EcoRI restriction sites were found in the HLA-DQ beta gene from 3 patients with early-onset periodontitis. In addition to these 20 subjects, an additional 80 subjects (40 patients and 40 healthy individuals) were screened for the atypical BamHI restriction site using the polymerase chain reaction method. It was detected in 7 patients with early-onset periodontitis, 1 patient with adult periodontitis, and 3 healthy subjects. No clinical differences except age were found between patients with this gene variation and other patients. Interestingly, all 3 healthy subjects with this gene variation were from subjects whose family members developed early-onset periodontitis with the gene variation. Atypical BamHI and EcoRI restriction sites and 41-nt repeated sequence were found in the intron before the third exon of HLA-DQB gene. These results suggest that these intronic gene variations may be useful as gene markers for a subpopulation of early-onset periodontitis and might affect immune reactions such as antigen recognition.

Adolescent↗

Recurrent generalized lichen nitidus associated with amenorrhea.

A case of recurrent generalized lichen nitidus is reported. The eruptions developed in the proliferative phase of the menstrual cycle, but there has been a marked improvement after administration of estrogen and progesterone for the treatment of amenorrhea. Hormonal factors may play a role in the development of lichenoid tissue reaction in the lesions of this disease.

Adult↗