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T Tsuchida

Publications and source records attributed to T Tsuchida.

At least 37 records · Page 2Linked to original sources
PubMed1994

A host-vector system for a cellulose-producing Acetobacter strain.

An indigenous plasmid, named pAH4, was detected in a cellulose-producing Acetobacter strain. This plasmid, consisting of 4002 bp, contained an AT-rich region and encoded several open reading frames, as deduced by the complete nucleotide sequence. One of the putative open reading frames showed homology with replication proteins of other plasmids. A shuttle vector of Escherichia coli and this strain was constructed by connecting pAH4 to pUC18. Electroporation of the shuttle vector into the strain yielded 1.7 x 10(5) ampicillin resistant transformants per microgram DNA. The shuttle plasmid was very stably maintained in the strain.

Acetobacter↗
PubMed1994

Chemoprevention effects on bronchial squamous metaplasia by folate and vitamin B12 in heavy smokers.

The purpose of this study was to observe the effects of folate and vitamin B12 on bronchial squamous metaplasia with cellular atypia, known to be a precancerous change, in heavy smokers. Cases of squamous metaplasia were recognized on sputum cytologic study. The location of bronchial lesions was identified by bronchofiberoscopy in all cases. The grade of cellular atypia was evaluated on the basis of histologic specimens. Thirty-eight patients with squamous metaplasia, including 21 patients receiving folate and vitamin B12 and 17 patients without any medication, were investigated prospectively for 1 year. Consecutive bronchofiberoscopic examinations were performed in each patient in 3 to 4 months after the first examination in order to evaluate the lesions. Grades of cellular atypia were examined by histologic specimens using a scoring system from 0 to 3. There was no significant difference in mean scores at entry in the medication group (1.7) and control group (1.4). The medication group showed significant decrease in mean scores (0.4) while the control group had no change in mean scores (1.2) at termination. Plasma levels in the medication group were significantly increased at termination of the study while those of the control group showed a slight decrease. The results show that the cellular atypia squamous metaplasia in heavy smokers can be reduced by administration of folate and vitamin B12.

Adult↗
PubMed1994

[Effective measures against side effects by increasing ACNU dose for malignant glioma: effects on digestive organs].

Loading therapy consisting of the ACNU regimen was instituted as postoperative anticancer chemotherapy for malignant gliomas. The efficacy rate of the regimen was 25% at a dose of 3 mg/kg. A high incidence of hematological changes, such as leukopenia (neutropenia) and thrombocytopenia, were observed after chemotherapy. The former could be prevented by the administration of G-CSF, but platelet infusions were necessary in some patients for amelioration of thrombocytopenia. Gastroenterological symptoms, such as nausea and vomiting, were also frequently noted. Granisetron (Kytril), which is a recently developed selective competitive inhibitor of the 5-HT3 receptor, was used for the treatment of these adverse effects, and was found to be clinically effective.

Adult↗
PubMed1993

HLA-A1 and HLA-A3 T cell epitopes derived from influenza virus proteins predicted from peptide binding motifs.

The potential value of peptide binding motifs of HLA class I molecules for the prediction of viral epitopes presented to T cells has been analyzed for two common HLA alleles. CTL generated against type A influenza virus recognize peptide epitopes derived from the nucleoprotein (NP) and basic polymerase 1 presented by HLA-A1, and epitopes derived from NP presented by HLA-A3. Distinct peptide binding motifs with characteristic anchor residues were previously identified for each of these class I molecules based on the sequences of endogenous peptides: for HLA-A1, position 3 = Asp or Glu and position 9 = Tyr; for HLA-A3, position 2 = Leu and position 9 = Lys or Tyr. Six peptides containing the HLA-A1 binding motif were identified within the sequences of the NP and basic polymerase 1 proteins, and one peptide containing the HLA-A3 motif was identified in the NP molecule. Three of the six HLA-A1 peptides and the one HLA-A3 NP peptide could bind to HLA-A1 or HLA-A3, respectively, in an in vitro peptide binding assay. Two of the HLA-A1-binding peptides could sensitize target cells for lysis by influenza virus-immune CTL populations restricted by HLA-A1 (NP 44-52 CTELKLSDY and PB1 591-599 VSDGGPNLY), and the one HLA-A3 NP peptide (NP 265-273 ILRGSVAHK) could sensitize target cells for lysis by HLA-A3-restricted influenza-immune CTL. Each peptide was also shown to be able to induce peptide-specific class I-restricted CTL in vitro, and the CTL generated against two of these peptides could specifically recognize virus-infected targets. Thus, these peptide binding motifs can be used to construct immunogenic synthetic epitopes which are capable of inducing antiviral T cell-mediated immune responses.

Amino Acid Sequence↗
PubMed1993

Folliculo-stellate cells in the human anterior pituitary express cytokeratin.

Recent studies have suggested that the anterior pituitary is derived not from Rathke's pouch, but instead from neuroectoderm. To address this controversy and the differentiation of the adenohypophysis, we evaluated folliculo-stellate cells from 7 human pituitaries using a panel of immunohistochemical stains. The panel included antibodies to a low molecular weight cytokeratin (CK-8), a broad spectrum of cytokeratins (AE 1/AE 3), S-100 protein, vimentin, and glial fibrillary acid protein. The most intense immunostaining was observed with the antibody to broad spectrum cytokeratins. Less intense immunohistochemical staining of folliculo-stellate cells was observed with the antibodies against glial fibrillary acidic protein and S-100 protein. Immunoblotting of anterior pituitary tissue obtained from 3 autopsied patients showed that cytokeratins identified in the anterior pituitary were of low molecular weight (40 to 56 Kd). These results indicate that folliculo-stellate cells show epithelial differentiation, and support the hypothesis that the anterior pituitary is derived from Rathke's pouch.

Blotting, Western↗
PubMed1993

Short report: effect of sucralfate on angiogenesis in granulation tissue of acetic acid-induced gastric ulcers in rats.

We investigated the effect of sucralfate on angiogenesis in granulation tissue of gastric ulcers induced by acetic acid in rats using the carmine dye method. Intragastric administration of sucralfate at a dose of 500 mg/kg twice daily for 9 days significantly accelerated ulcer healing and significantly increased the extent of angiogenesis in the ulcer base on the tenth day after ulcer induction. As we reported previously, intragastric administration of cimetidine at a dose of 100 mg/kg once daily for 9 days decreased the extent of angiogenesis on the tenth day. However, combination treatment using sucralfate and cimetidine accelerated ulcer healing significantly, without altering the extent of angiogenesis. It is concluded, therefore, that the treatment with sucralfate may be effective in peptic ulcer disease from the standpoint of angiogenesis in the ulcer base.

Animals↗
PubMed1993

Clinical significance of serum hepatocyte growth factor levels in liver diseases.

Serum levels of human hepatocyte growth factor (hHGF) in patients with various liver diseases were determined using an ELISA kit to explore its clinical significance. Significantly high levels of serum hHGF were found in patients with acute hepatitis, fulminant hepatitis, liver cirrhosis, and hepatocellular carcinoma. Increased levels of hHGF were observed during severe liver injury in patients who died of fulminant hepatitis. However, the levels returned to normal during the repair process of liver injury in the surviving cases. In patients with liver cirrhosis, serum hHGF levels were negatively correlated with serum albumin (Alb) levels. These results indicate that serum hHGF levels are not useful for detecting repair processes of the injured liver, but serve as an index of the severity of liver dysfunction in various liver diseases.

Adult↗
PubMed1992

Identification of a src family protein specifically expressed in rat astrocytes by immunohistochemistry and double immunofluorescent study.

Identification of a src-related tyrosine kinase and its regional and cellular distributions were studied in rat brain. The study was performed using a specific antibody raised against a synthetic peptide corresponding to the conserved autophosphorylation site of src-family tyrosine kinases. The antibody (alpha-src antibody) recognized a 43 kDa polypeptide in plasma membrane enriched fraction. The immunohistochemical data revealed that the polypeptide is localized in astrocytes of corpus callosum and fimbria hippocampus. The presence of this src-related protein in astrocytes suggests that it may have some control in their proliferation and differentiation.

Animals↗
PubMed1992

Fluorescent dye rhodamine 6G as a molecular probe to study drug resistance of C6 rat glioma cells.

A study was made of the membrane transport of cytoplasm and mitochondria stained fluorescence dye Rhodamine 6G (R6G). In rat glioma C6 cells and 1-(4-amino-2-methyl-5-pyrymidinyl)-methyl-3-(2-chloroethyl) -3-nitrosourea hydrochloride (ACNU) and vincristine (VCR) resistant cell lines (C6/ACNU, C6/VCR), the rate of uptake of R6G decreased in C6/VCR cells, but verapamil increased the intracellular accumulation of R6G in C6/VCR. The intracellular accumulation of R6G of C6/ACNU cells was essentially the same as that of wild-type cells. C6/ACNU cells did not show cross resistance and were sensitive to VCR and cisplatin. C6/VCR cells showed cross resistance to ACNU and CDDP, but C6/VCR cells in the presence of verapamil were more sensitive to drugs than C6/VCR cells in the absence of verapamil. We conclude that the reduction of R6G fluorescence staining intensity in C6/VCR cells compared to wild-type cells may be associated with the mechanism of multidrug resistance (MDR) but does not reflect the mechanism of resistance to ACNU. Verapamil increased the accumulation of R6G in C6/VCR cells and overcame MDR, suggesting that there is a correlation between the MDR overcoming effect and enhancement of R6G accumulation, and that this correlation validates the use of the R6G staining test for clinical and laboratory investigation of MDR.

Animals↗
PubMed1992

Clinical evaluation of scleroderma spectrum disorders using a points system.

We have established a new diagnostic method using a points system to evaluate patients with early scleroderma and those with scleroderma spectrum disorders (SSD). To examine the clinical usefulness of this method, it was applied to a total of 215 cases including 97 patients with scleroderma, 32 with SSD, 28 with presumed primary Raynaud's phenomenon (RP) and 58 with other connective tissue disorders (CTD). A total score was obtained for each patient as the sum of the following five factors: (1) extent of skin sclerosis (maximum, 10 points); (2) pulmonary changes (maximum, 4 points); (3) antinuclear antibodies (maximum, 5 points); (4) pattern of Raynaud's phenomenon (maximum, 3 points); and (5) nailfold bleeding (maximum, 2 points). Of the 97 scleroderma patients, 86 (89%) had 9 or more points, and of the 32 SSD patients, 28 (88%) had 5 to 8 points. In contrast, all patients with presumed primary RP and 54 of 58 (93%) patients with other CTD had 0 to 4 points. These data suggest that this diagnostic method is very useful not only for clinical evaluation of SSD, but also for the differentiation of scleroderma and SSD from other CTD and primary RP.

Connective Tissue Diseases↗
PubMed1992

Evaluation of transcatheter arterial embolization with epirubicin-lipiodol emulsion for hepatocellular carcinoma.

A total of 18 patients with hepatocellular carcinoma (HCC) were treated by transcatheter arterial embolization (TAE) with a 4'-epi-doxorubicin (EDX)-lipiodol emulsion. Infusion of the EDX-lipiodol emulsion (EDX-L) via the hepatic artery was followed by the injection of gelatin sponge in 12 cases. The response and survival of these 12 patients following EDX-L treatment were compared with those of 42 subjects treated with a doxorubicin-lipiodol emulsion (DX-L) and those of 23 patients treated by TAE with gelatin sponge (GS) only. In the group treated with EDX-L, nine cases were AFP-positive in sera and four showed a decrease in serum AFP values to less than 10% of the pretreatment level. Seven cases showed a partial response, and nine cases showed no change in the size of the tumor. In the group treated with EDX-L, nine cases are alive, and the oldest has survived for more than 431 days since the treatment. The half-year survival value was 57%, and the 1-year survival value was 49%. These values did not differ significantly from those calculated for the group treated with DX-L. The 1-year survival value determined for patients treated with a lipiodol emulsion (EDX-L or DX-L) followed by GS was 65%, and the 2-year survival value was 39%. These results rates are significantly better than those obtained in patients treated with GS only (1-year survival, 39%; 2-year survival, 13%.

Aged↗
PubMed1992

Effectivity and safety of mannitol treatment for acute hepatic failure in rats.

In rats with D-galactosamine-induced hepatic failure, 14C-D-mannitol transport into the brain was accelerated through an increase of vesicular transport via the blood-brain barrier and thus brain mannitol contents increased. However, the osmolarity of the brain tissue changed little and the mortality was decreased by mannitol infusion to acute hepatic-failure rats. Experimental data indicate the effectivity and safety of hypertonic mannitol therapy for cerebral edema in acute hepatic failure.

Animals↗
PubMed1992

Colloid cysts of the third ventricle: immunohistochemical evidence for nonneuroepithelial differentiation.

The histogenesis of colloid cysts (CCs) of the third ventricle has been a subject of controversy. We examined, using immunohistochemical techniques, four CCs for the presence of cytokeratins (CKs), glutathione S-transferase isoenzymes (GST-pi, GST-mu), and glial fibrillary acidic protein. Antibodies to both low molecular weight CKs (anti-CK8) and to a mixture of CKs (AE1/AE3) were used. For comparison, normal fetal and adult choroid plexus, ependyma, and nasal mucosa were also examined. The epithelium lining all four CCs showed positive immunostaining for the CKs and GST-pi but not for GST-mu or glial fibrillary acidic protein. Fetal and adult nasal mucosa showed a pattern of immunohistochemical staining almost identical to that of CCs. In contrast, fetal and adult choroid plexus tissue showed positive immunostaining for GST-pi and low molecular weight CKs but not for the CK mixture (AE1/AE3). Fetal and adult ependyma were negative for both CKs and GST-pi. These results suggest that CCs differentiate along nonneural lines distinct from the neuroepithelial differentiation of the choroid plexus and ependyma.

Adult↗
PubMed1992

Gangliosides of melanoma.

The relationships between the ganglioside composition of melanomas and their biologic behavior were investigated. (1) The amount of GM2 and/or GD2 in melanoma cells injected into nude mice correlated with the tumor growth rate. (2) GD2 content of melanoma cell lines correlated with sensitivity to radiation and vincristine. (3) GM2 expression of melanoma cells correlated with sensitivity to lymphokine-activated killer cells. (4) Gangliosides inhibited the proliferation of human T cells stimulated with interleukin-4 or interleukin-2. Based on these results, we proposed a hypothesis for the role of melanoma-associated gangliosides in the biologic behavior of melanomas and suggested a prospective melanoma treatment related to the gangliosides.

Animals↗