2976
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Okubo M, Kokubun M, Nishimaki T, Kasukawa R, Ohto H, Yamamoto K, Muller S. T cell epitope mapping of U1-A RNP. ARTHRITIS AND RHEUMATISM 1995; 38:1170-2. [PMID: 7639817 DOI: 10.1002/art.1780380823] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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2977
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Chauhan D, Uchiyama H, Urashima M, Yamamoto K, Anderson KC. Regulation of interleukin 6 in multiple myeloma and bone marrow stromal cells. Stem Cells 1995; 13 Suppl 2:35-9. [PMID: 8520509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We and others have shown that some freshly isolated multiple myeloma (MM) cells and derived cell lines express interleukin 6 (IL-6) receptors and proliferate in vitro in response to IL-6; a subset of MM cells also expresses IL-6 mRNA, is intracytoplasmic IL-6 positive and secretes IL-6. We have shown that MM cells express the cell surface adhesion molecules CD29/CDw49d(VLA-4), CD18/CD11a(LFA-1) and CD44, and may localize to marrow via specific adherence to both extracellular matrix proteins and to bone marrow stromal cells (BMSCs). MM cell adhesion triggers IL-6 secretion by normal and MM BMSCs and related IL-6-mediated tumor cell growth. Our attempts to block MM cell adhesion to BMSC-induced IL-6 secretion by using antibodies to CD29/CDw49d, CD18/11a, and/or CD44 demonstrated minimal effects, suggesting that another ligand-receptor interaction triggers IL-6 secretion when MM cells and BMSCs are juxtaposed. Both MM cells and BMSCs express CD40. Triggering of MM cells and BMSCs via CD40 upregulates IL-6 secretion in both MM cells and MM-derived cell lines, as well as BMSCs and BMSC lines, suggesting the possibility of both autocrine and paracrine MM cell growth triggered via CD40. Finally, experiments using the LP 101 BMSC line transiently transfected with IL-6 promoter fragments linked to chloramphenicol acetyltransferase reporter gene demonstrate that adhesion of MM cells induces IL-6 gene transcription in BMSCs, which is conferred via the NF-kappa B binding motif.(ABSTRACT TRUNCATED AT 250 WORDS)
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2978
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Matsuyama J, Yamamoto K, Miwatani T, Honda T. Monoclonal antibody developed against a hemolysin of Bacillus thuringiensis. Microbiol Immunol 1995; 39:619-22. [PMID: 7494502 DOI: 10.1111/j.1348-0421.1995.tb02251.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A total of five hybridoma cell lines that produced monoclonal antibodies (MAb) against a hemolysin (Bt-hemolysin) produced by Bacillus thuringiensis were established and characterized. All of these monoclonal antibodies reacted similarly not only to Bt-hemolysin but also to a hemolysin (Bc-hemolysin) produced by B. cereus, suggesting that the two hemolysins are immunologically indistinguishable. The MAb developed in this study was also successfully applied for rapid and simple purification of both Bt- and Bc-hemolysins by immunoaffinity column chromatography. The partial N-terminal amino acid sequence of the purified hemolysins was determined to be Ile-Glu-Gln-Thr.
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2979
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Kobayashi H, Yamamoto K, Eguchi M, Kubo M, Nakagami S, Wakisaka S, Kaizuka M, Ishii H. Rapid detection of mycoplasma contamination in cell cultures by enzymatic detection of polymerase chain reaction (PCR) products. J Vet Med Sci 1995; 57:769-71. [PMID: 8519917 DOI: 10.1292/jvms.57.769] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Enzymatic detection of polymerase chain reaction (ED-PCR) was applied for rapid and easy identification of mycoplasmas from contaminated cell culture. This method was based on the capture of amplified products via biotin-streptavidine affinity and the detection of an incorporated hapten in amplified products with enzyme-linked antibody. Primers corresponding to common sequence of Mollicutes in 16S ribosomal RNA dominated gene was used. Nineteen of twenty Mollicutes so far reported as cell contaminants appeared positive by ED-PCR, whereas remaining one, Acholeplasma axanthum, appeared negative. Samples from sixty-two cell culture were tested for contamination of mycoplasmas by means of ED-PCR, cultivation, and electronmicroscopy. The results of ED-PCR were the same as those of cultivating method. The time required for all the detection process in ED-PCR was about 5 hr for 20 samples. We suggest that ED-PCR can be used in the rapid detection of mycoplasms from cell culture.
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2980
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Furuya Y, Yamamoto K, Kohno N, Yamamoto M, Saitoh Y. Serum concentrations of 5-fluorouracil achieved with nocturnal constant-rate infusion in patients with disseminated cancer. Cancer Lett 1995; 94:207-11. [PMID: 7634249 DOI: 10.1016/0304-3835(95)03851-m] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Nocturnal infusion of 5-fluorouracil (FUra) was performed in nine patients with disseminated cancer. Three gastric, three colon and three breast cancer patients were administered 300 mg/m2 FUra continuously for 10 h per day from 2100 h to 0700 h for more than 20 consecutive days. In the first three patients, who were treated by drip infusion without the use of a volumetric pump, serum FUra concentrations ranged widely, from 27 to 130 ng/ml, even though the rate of administration was re-adjusted four times during the night. The last six patients were treated using a volumetric pump, and FUra concentrations in serum ranged from 175 to 378 ng/ml, and displayed no circadian rhythm. Although the dose intensity and area under the curve of FUra in these patients were high, neither myelosuppression nor other side effects were observed.
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2981
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Yamamoto K, Hayashi Y, Hanada R, Kikuchi A, Ichikawa M, Tanimura M, Yoshioka S. Mass screening and age-specific incidence of neuroblastoma in Saitama Prefecture, Japan. J Clin Oncol 1995; 13:2033-8. [PMID: 7636545 DOI: 10.1200/jco.1995.13.8.2033] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
PURPOSE To provide the population-based incidence rate of neuroblastoma and to determine the effect of mass screening on the annual age-specific incidence of the tumor in Saitama Prefecture, Japan, from 1981 to 1992. METHODS Data on screened infants and patients detected by the screening were obtained from the records of the Prefectural Screening Center. Data on neuroblastomas in this area were obtained from the Children's Cancer Registry of the Saitama Prefectural Government (Prefectural Registry) and from the Japan Children's Cancer Registry (National Registry). Population data were obtained from the Prefectural Census. Mass screening for 6-month-old infants was performed by qualitative assessment of urinary vanillylmandelic acid (VMA) from June 1981 to September 1989 and by quantitative measurement of VMA/creatinine (Cre) and homovanillic acid (HVA)/Cre from October 1989 to December 1992. RESULTS Between 1981 and 1992, 199 cases of neuroblastoma, which include 74 cases detected by mass screening, were identified in Saitama Prefecture. The incidence rate for children under 15 years of age increased from 6.4/10(6) to 20.1/10(6), that for children 0 to 4 years of age increased from 17.0/10(6) to 64.1/10(6), and that for infants under 1 year of age increased from 27.9/10(6) to 260.4/10(6) during these 12 years. No significant reduction in the incidence rate was observed for children over 1 year of age. CONCLUSION The incidence rate for children under 15 years of age increased with mass screening. The rate for infants was sharply increased, with no corresponding decrease in the rate for children at older ages. These data suggest that there is a subset of neuroblastoma that can be detected by mass screening at 6 months of age but would not be diagnosed later clinically.
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2982
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Kodobayashi M, Yamamoto K, Takahara S, Okuyama A, Takashima N, Sawada M, Yanaihara C, Kurokawa N. Gel chromatographic analysis of cyclosporin and its metabolites in human blood compartments. J Pharm Pharmacol 1995; 47:693-7. [PMID: 8583375 DOI: 10.1111/j.2042-7158.1995.tb05862.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Gel chromatography combined with specific and non-specific cyclosporin radioimmunoassays was adopted for quantitative analysis of cyclosporin and metabolites in free and protein-bound forms in blood compartments of kidney transplant patients. The analytical method was proved to be useful for the purpose, although plasma protein-bound forms of neither cyclosporin nor metabolites could be quantitated in the system. The present study also provided, by gel chromatographic analysis, additional examples to prove that concentrations of cyclosporin metabolites in blood compartments may not be deduced or inferred simply from those of cyclosporin.
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2983
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Sato T, Yamamoto K, Ouchi A, Imaoka Y, Tokumura H, Matsushiro T. Undifferentiated carcinoma of the duodenal ampulla. J Gastroenterol 1995; 30:517-9. [PMID: 7550864 DOI: 10.1007/bf02347570] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
This report demonstrates a case of undifferentiated carcinoma of the duodenal ampulla. A 74-year male experienced jaundice lasting for 3 weeks. An upper gastrointestinal series demonstrated a polypoid, ovoid filling defect in the second portion of the duodenum, and duodenoscopy disclosed a protruding mass involving the orifice of the papilla of Vater. Cholangiography demonstrated obstruction due to compression in the terminal common bile duct. Pylorus-preserving pancreatoduodenectomy was performed on the diagnosis of ampullary carcinoma. The gross specimen showed a polypoid mass, measuring 3.5 cm in diameter, in the ampulla, located mainly in the duodenal submucosal layer and invading the terminal common bile duct. Histologically, the tumor was small cell type, undifferentiated carcinoma, arising from the duodenal epithelium adjacent to the ampulla.
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2984
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Sun X, Shimizu H, Yamamoto K. Identification of a novel p53 promoter element involved in genotoxic stress-inducible p53 gene expression. Mol Cell Biol 1995; 15:4489-96. [PMID: 7623839 PMCID: PMC230688 DOI: 10.1128/mcb.15.8.4489] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
p53 is recruited in response to DNA-damaging genotoxic stress and plays an important role in maintaining the integrity of the genome. We show that exposure of cells to various genotoxic agents, including anticancer drugs such as mitomycin and 5-fluorouracil, results in an increase in p53 mRNA levels and in p53 promoter activation, indicating that the p53 genotoxic stress response is partly regulated at the transcriptional level. The results of the p53 promoter analysis show that a novel p53 promoter element, termed a p53 core promoter element (from -70 to -46), is essential for basal p53 promoter activity and promoter activation induced by genotoxic agents such as anticancer drugs and UV. Although a kappa B motif partially overlaps with this element and those genotoxic agents activate NF-kappa B, it does not play a major role in p53 genotoxic stress response: NF-kappa B p65 expression did not induce significant p53 promoter activation, and NF-kappa B inhibitors (N-acetyl cysteine and I kappa B alpha) did not inhibit genotoxic stress-inducible p53 promoter activation. Finally, we characterized nuclear factors, the binding of which to the p53 core promoter element is essential for basal p53 promoter activity and p53 promoter activation induced by genotoxic agents.
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2985
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Miyatake K, Yamaguchi T, Takatsuji H, Igarashi T, Nakamura K, Saeki F, Kato K, Suzuki M, Kamada T, Yamamoto K. [SH/TA-508 clinical phase II study: dose evaluation of SH/TA-508 in echocardiography]. J Cardiol 1995; 26:111-33. [PMID: 7674143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A cooperative study was conducted at 18 institutions to evaluate the safety and usefulness of SH/TA-508, a contrast medium for ultrasound diagnosis, and to find its optimum dose. One hundred and one patients with confirmed or suspected ischemic heart disease were examined with two-dimensional echocardiography, and 95 patients with mild mitral insufficiency were studied with the color Doppler method. The contrast medium was administered at low-dose (1.5-1.6g galactose) and high-dose (3.0-3.2 g galactose) levels at concentrations of 200, 300 and 400 mg/ml. The contrast effect was evaluated into five grades by two-dimensional echocardiography: - (ineffective), + (weak), 2+ (moderate), 3+ (good), 4+ (excessive effect) and into four grades with the color Doppler method, - (ineffective), + (weak), 2+ (optimum), 3+ (excessive effect). The two-dimensional echocardiographic studies showed effects graded at 2+ and above in most patients (83-93%). These findings were significantly more common in patients who had received the 300 and 400 mg/ml concentrations than in those who received the 200 mg/ml concentration. Statistical analysis found no significant differences between the high-dose and low-dose groups. Color Doppler echocardiography found signal enhancement graded at 2+ and above in 80-93% of cases. There were no significant differences in enhancement effect attributable to concentration or total dose. However, since excessive signal intensity was seen quite frequently, the dose levels in the present study were considered to be a little too high. Side effects includes transient feelings of warmth or cold, and the incidence of side effects was higher at higher doses and concentrations. The results show that the optimum concentration for two-dimensional echocardiography is 300 mg/ml and for color Doppler 200 mg/ml. No particular safety problems were seen with SH/TA-508, and this contrast medium is useful in echocardiography of the left ventricle and in enhancing mitral regurgitation signals in color Doppler examinations. Therefore, a phase III multicenter trial should be performed.
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2986
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Taniguchi T, Uchima-Senaga NF, Takarada Y, Shibata S, Tsukamoto T, Yamamoto K, Honda T. Use of a new oligonucleotide probe for detection of colonization factor antigen III gene in enterotoxigenic Escherichia coli. Eur J Clin Microbiol Infect Dis 1995; 14:713-6. [PMID: 8565993 DOI: 10.1007/bf01690882] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
An alkaline phosphatase-labeled 30-mer oligonucleotide probe was designed to detect the gene for pilus colonization factor antigen III (CFA/III) of the human type of enterotoxigenic Escherichia coli (ETEC). The CFA/III probe was used to identify CFA/III-producing ETEC among 303 Escherichia coli obtained from subjects with traveler's diarrhea. Six isolates positive for the CFA/III gene were found. This result was confirmed immunologically by using a specific monoclonal antibody developed against CFA/III. These six isolates, isolated from travelers returning from India, Pakistan and China, were all positive for the gene of heat-labile enterotoxin and possessed an identical serotype (025:H-).
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2987
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Kamasaka H, Uchida M, Kusaka K, Yoshikawa K, Yamamoto K, Okada S, Ichikawa T. Inhibitory effect of phosphorylated oligosaccharides prepared from potato starch on the formation of calcium phosphate. Biosci Biotechnol Biochem 1995; 59:1412-6. [PMID: 7549090 DOI: 10.1271/bbb.59.1412] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The inhibitory effect of phosphorylated oligosaccharides, which were prepared from potato starch, on the formation of calcium phosphate in vitro were investigated. Phosphorylated oligosaccharides from potato were fractionated by ion-exchange chromatography into two fractions, PO-1 and PO-2. Fraction PO-1 was composed of maltotriose, maltotetraose, and maltopentaose to which one phosphate group was attached. Fraction PO-2 was predominantly composed of maltopentaose and maltohexaose to which at least two phosphate groups were attached. The average degree of polymerization of dephosphorylated PO-1 and PO-2 was evaluated to be 4.02 and 5.82, respectively. Fraction PO-2 was the main component having an inhibitory effect on calcium phosphate formation. In addition, among the phosphorylated monosaccharides, glucose-1,6-diphosphate and fructose-1,6-diphosphate were more effective inhibitors of the formation of calcium phosphate than glucose-6-phosphate and fructose-6-phosphate. These results suggest that the strength of the inhibitory effect might depend on the number of phosphate groups attached to each sugar molecule.
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2988
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Suehiro T, Matsumata T, Itasaka H, Yamamoto K, Kawahara N, Sugimachi K. Clinicopathologic features and prognosis of resected hepatocellular carcinomas of varied sizes with special reference to proliferating cell nuclear antigen. Cancer 1995; 76:399-405. [PMID: 8625120 DOI: 10.1002/1097-0142(19950801)76:3<399::aid-cncr2820760309>3.0.co;2-o] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Proliferating cell nuclear antigen (PCNA) is an intranuclear protein that is linked closely to the cell cycle. An immunohistochemical study was performed on the expression of PCNA in various sized hepatocellular carcinomas (HCCs) to determine the relation between the proliferative activity of cancer cells and prognosis. METHODS One hundred forty-one neoplasms resected from 141 patients who underwent hepatic surgery for HCC at Kyushu University hospital from April, 1991, to July, 1993, were studied immunohistochemically using monoclonal antibody for PCNA (PC10), and analyzed for a possible correlation between PCNA labeling index (PCNA-LI) and the prognosis of patients with HCC. RESULTS Proliferating cell nuclear antigen reactive cancer cells were observed throughout the HCC. The PCNA-LI ranged from 1.2%-91.6%, with a mean of 37.7%. The high PCNA-LI (> 37.7) group showed a significantly higher incidence of tumor thrombus in the portal vein, higher Edmondson's Grade, and a higher recurrence rate than the low PCNA-LI (< 37.7) group. Hepatocellular Carcinomas were divided into three groups according to tumor size. Based on the clinicopathologic findings, in small (< 30 mm) HCCs, the high PCNA-LI (> 29.0) group showed a significant higher Edmondson's grade and a higher recurrence rate than the low PCNA-LI (< 29.0) group. In medium (30-60 mm) HCCs, the high PCNA-LI (> 36.1) group showed a significantly higher recurrence rate than the low PCNA-LI (< 36.1) group, although there was no difference in the pathologic findings between the high (> 59.4) and low (< 59.4) PCNA-LI groups. CONCLUSIONS Proliferating cell nuclear antigen labeling index is closely related to cell differentiation and the prognosis of HCC. Furthermore, PCNA-LI was found to be useful in predicting the intrahepatic spread and prognosis of small (< 30 mm) and medium (30-60 mm) but not large (> 60 mm) HCCs.
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2989
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Kobayashi M, Sugiyama M, Yamamoto K. Isolation of cDNAs encoding GTP cyclohydrolase II from Arabidopsis thaliana. Gene 1995; 160:303-4. [PMID: 7642114 DOI: 10.1016/0378-1119(95)00246-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A GTP cyclohydrolase II-encoding gene from Arabidopsis thaliana was isolated through functional complementation of a mutant of Escherichia coli, BSV18, deficient in this protein. The derived amino-acid sequence constitutes a polypeptide of 27 kDa and shows 37-58% identity with previously published sequences of Escherichia coli, Bacillus subtilis, Photobacterium leiognathi and P. phosphoreum.
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2990
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Roh JH, Takenaka Y, Suzuki H, Yamamoto K, Kumagai H. Escherichia coli K-12 copper-containing monoamine oxidase: investigation of the copper binding ligands by site-directed mutagenesis, elemental analysis and topa quinone formation. Biochem Biophys Res Commun 1995; 212:1107-14. [PMID: 7626099 DOI: 10.1006/bbrc.1995.2083] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Copper-containing monoamine oxidase (EC 1.4.3.6) from Escherichia coli is a periplasmic enzyme containing topa quinone in addition to divalent copper as a cofactor. The amino acid sequence of E. coli monoamine oxidase was compared to several cloned amine oxidase genes and five well-conserved histidine residues were found. Site-directed mutagenesis studies were performed to determine which histidine residue serves as the binding ligand to the copper. Enzyme activity, absorption spectrum, and atomic absorption spectrophotometry of the mutant enzymes indicated that histidines 470, 554, and 556 are the copper binding ligands. The absorption spectra of phenylhydrazine derivatives suggested that copper is necessary for topa quinone formation.
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2991
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Yamamoto K, Ishida H. Interpretation of reflection and transmission spectra for thin films: transmission. APPLIED OPTICS 1995; 34:4177-4185. [PMID: 21052243 DOI: 10.1364/ao.34.004177] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The optical behavior of a thin film, that is, peak positions and intensities, is discussed for transmission under a thin-film approximation. The infrared transmission spectra of thin films, both standing films and those on dielectric substrates, are simulated for s and p polarization at various angles of incidence. For spectral simulation, the matrix method is used in conjunction with noise-free complex refractive indices based on the dispersion theory. The peak positions in the simulated spectra are compared with transverse optic and longitudinal optic frequencies based on the macroscopic theory. The simulated peak intensities for the standing films are compared with the prediction based on the thin-film approximation. Furthermore, it is found from the spectral simulation for thin films on dielectric substrates that the peak intensity for a thin film may depend on the thickness and refractive index of the substrate.
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2992
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Yamamoto K, Ikeda Y, Masuko K, Nakai Y, Kato T, Hasunuma T, Mizushima Y, Nishioka K. High frequencies of identical T-cell clonotypes accumulating in different areas of synovial lesions of rheumatoid arthritis patients. Ann N Y Acad Sci 1995; 756:208-10. [PMID: 7645835 DOI: 10.1111/j.1749-6632.1995.tb44513.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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2993
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Yamamoto M, Yamauchi T, Yamamoto K, Kobayashi T. Activated sialidase activity in transformed lymphocytes by Epstein-Barr (EB) virus of sialidosis type I (cherry-red spot-myoclonus syndrome). J Neurol Sci 1995; 131:105-7. [PMID: 7561940 DOI: 10.1016/0022-510x(95)00102-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We report a new Japanese family of sialidosis type I. The sialidase activity was deficient in the lymphocytes of 2 patients (6.8% (sister) and 12.5% (brother) of control mean). However, surprisingly, using the transformed lymphocytes by EB virus, this activity was activated to 51.7% (sister) and 49.5% (brother) of control mean, respectively. Although the mechanism for this activation was not known, we discussed the possible mechanisms for this phenomenon.
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2994
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Hashimoto W, Suzuki H, Yamamoto K, Kumagai H. Effect of site-directed mutations on processing and activity of gamma-glutamyltranspeptidase of Escherichia coli K-12. J Biochem 1995; 118:75-80. [PMID: 8537328 DOI: 10.1093/oxfordjournals.jbchem.a124894] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
gamma-Glutamyltranspeptidase [EC 2.3.2.2] of Escherichia coli K-12 is thought to be synthesized from a single precursor polypeptide into a heterodimeric form through post-translational processing. Cells of a gamma-glutamyltranspeptidase-overproducing transformant of E. coli K-12 were fractionated and the localization of the enzyme was examined by Western blot analysis. The periplasmic fraction only contained the mature form of gamma-glutamyltranspeptidase, membrane fraction only contained the precursor of gamma-glutamyltranspeptidase, and no precursor of gamma-glutamyltranspeptidase was detected in the cytoplasmic fraction. Amino acid residues at the cleavage site for processing into the large and small subunits were substituted by site-directed mutagenesis. The processing phenotypes of six mutants were examined by Western blot analysis, and their gamma-glutamyltranspeptidase activities were measured. Mutations at the N-terminal amino acid residues of the small subunit (Thr-391, Thr-392, and His-393) prevented the maturation of the enzyme and the immature mutants exhibited no enzymatic activity. A mutation at the C-terminal residue of the large subunit (Gln-390) had less effect on the processing and enzymatic activity. These results suggest that the sequence of threonyl-threonyl-histidinyl residues at the N-terminal of the small subunit is very important for the processing of E. coli K-12 gamma-glutamyltranspeptidase and this processing is essential to the expression of gamma-glutamyltranspeptidase activity of E. coli K-12.
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2995
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Nagasawa H, Mitamura T, Sakamoto S, Yamamoto K. Effects of lycopene on spontaneous mammary tumour development in SHN virgin mice. Anticancer Res 1995; 15:1173-8. [PMID: 7653996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Effects of the chronic ingestion of lycopene, a carotenoid from tomato, on the development of spontaneous mammary tumours were examined in a high mammary tumour strain of SHN virgin mice. Beginning at 40 days of age, the control and the experimental groups were allowed free access to an AIN-76TM diet and a diet supplemented further with lycopene at the concentration of 5.0 x 10(-5)%, respectively. The treatment significantly suppressed the mammary tumour development, which suppression was associated with the decrease in the mammary gland activity of thymidylate synthetase, and serum levels of free fatty acid and prolactin. Body weight was little affected and no deleterious side-effects of lycopene were detected. All results show that lycopene could be promising as a chemopreventive agent for mammary and other types of tumours.
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2996
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Matsumoto N, Kita K, Kojima S, Yamamoto K, Irimura T, Miyagi M, Tsunasawa S, Toyoshima S. Lymphocyte isoforms of mouse p50 LSP1, which are phosphorylated in mitogen-activated T cells, are formed through alternative splicing and phosphorylation. J Biochem 1995; 118:237-43. [PMID: 8537319 DOI: 10.1093/oxfordjournals.jbchem.a124885] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
p50 is phosphorylated in mitogen-stimulated T cells, and translocated from the membrane to the cytosol after activation of protein kinase C. Sequence analysis of p50 revealed that it is identical with LSP1, a putative calcium-binding and actin-binding protein. lymphocyte form of p50 exhibits heterogeneity in the apparent molecular mass on SDS-PAGE, 50 and 52 kDa (pp50 and pp52), and each isoform exhibits heterogeneity in the isoelectric point, when examined by two-dimensional PAGE. When the two molecular mass variants of p50 were dephosphorylated with alkaline phosphatase, both isoforms showed the same apparent molecular mass of 50 kDa on SDS-PAGE, but could be distinguished by their distinct isoelectric points. Dephosphorylated pp50 (p50a) has an acidic pI compared with dephosphorylated pp52 (p50b). Comparison of the peptide maps of purified p50a and p50b on HPLC revealed that the difference was limited to one peptide peak. NH2-terminal sequence and mass spectrometric analyses of these peptides showed that the peptides derived from p50a and p50b had the same NH2-terminal amino acid sequence up to eight residues, but had distinct molecular masses, 5,533.4 and 6,318.6 Da, respectively. These data suggested that pp52 (p50b) is the product of the previously cloned cDNA and the reduction in the molecular mass of the p50a-derived peptide could be explained by deletion of six amino acid residues, EHLIRH or HLIRHQ.(ABSTRACT TRUNCATED AT 250 WORDS)
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2997
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Tajima H, Tajima N, Hiraoka Y, Yamamoto K, Kobayashi Y, Kumazaki T, Maeda S. Tuberculosis of the prostate: MR imaging. RADIATION MEDICINE 1995; 13:171-3. [PMID: 8539443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Tuberculosis of the genitourinary tract is still encountered in routine examinations. We present a case of tuberculosis of the prostate with its MR findings.
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2998
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Yoshimine Y, Tsukuba T, Isobe R, Sumi M, Akamine A, Maeda K, Yamamoto K. Specific immunocytochemical localization of cathepsin E at the ruffled border membrane of active osteoclasts. Cell Tissue Res 1995; 281:85-91. [PMID: 7621529 DOI: 10.1007/bf00307961] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The immunocytochemical localization of cathepsin E, a non-lysosomal aspartic proteinase, was investigated in rat osteoclasts using the monospecific antibody to this protein. At the light-microscopic level, the preferential immunoreactivity for cathepsin E was found at high levels in active osteoclasts in the physiological bone modeling process. Neighboring osteoblastic cells were devoid of its immunoreactivity. At the electron-microscopic level, cathepsin E was exclusively confined to the apical plasma membrane at the ruffled border of active osteoclasts and the eroded bone surface. Cathepsin E was also concentrated in some endocytotic vacuoles of various sizes in the vicinity of the ruffled border membrane, some of which appeared to be secondary lysosomes containing the phagocytosed materials. These results strongly suggest that this enzyme is involved both in the extracellular degradation of the bone organic matrix and in the intracellular breakdown of the ingested substances in osteoclasts.
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2999
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Ohkawa K, Hayashi N, Yuki N, Masuzawa M, Kato M, Yamamoto K, Hosotsubo H, Deguchi M, Katayama K, Kasahara A. Long-term follow-up of hepatitis B virus and hepatitis C virus replicative levels in chronic hepatitis patients coinfected with both viruses. J Med Virol 1995; 46:258-64. [PMID: 7561800 DOI: 10.1002/jmv.1890460316] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Dual infection with hepatitis B and C viruses is often encountered in endemic areas of both viruses. However, understanding of the clinical and virological implications is limited. The aim of this study was to investigate the role of each virus in liver injury and the interaction between the two viruses in dual infection with hepatitis B and C viruses. Three patients who had chronic infection with both hepatitis B and C viruses were examined, and a longitudinal study of both serum hepatitis B virus DNA and hepatitis C virus RNA levels over 4 years was undertaken. The results were correlated with serum alanine aminotransferase levels. Serum alanine aminotransferase values showed a relationship with hepatitis B virus replicative levels, but not with hepatitis C virus replicative levels in all 3 patients. Serial changes of replicative levels of both viruses were studied, and it was found that hepatitis C virus replicative levels were enhanced after the decline of hepatitis B virus replication in 1 of the 3 patients. In the remaining 2 patients, a transient rise of hepatitis C virus replicative levels in association with a decrease of hepatitis B virus replication was also observed during part of the follow-up period. These findings indicate that hepatitis B virus may play a dominant etiological role in liver injury, and that a suppressive action between hepatitis B and C viruses may occur in dual infection with both viruses.
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3000
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Kato T, Sasakawa H, Suzuki S, Shirako M, Tashiro F, Nishioka K, Yamamoto K. Autoepitopes of the 52-kd SS-A/Ro molecule. ARTHRITIS AND RHEUMATISM 1995; 38:990-8. [PMID: 7541994 DOI: 10.1002/art.1780380716] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE This study was undertaken to clarify the mechanisms responsible for the generation of anti-52-kd SS-A/Ro autoantibodies and to elucidate why, as has recently been reported, anti-52-kd autoantibodies preferentially recognize the denatured form rather than the native 52-kd molecule. METHODS Using a series of truncated 52-kd autoantigens, produced as beta-galactosidase fusion proteins in Escherichia coli, the B cell epitope distribution was probed with 18 anti-Ro-positive sera by immunoblotting and by enzyme-linked immunosorbent assay. RESULTS Nearly all the antigenicity of the molecule was found to be linked to its leucine zipper region. In a further study using 9 of the 18 sera, the antigenicity of the molecule was found to be mainly formed by multiple conformational epitopes, and one of these epitopes appeared to be universally recognized by all the sera tested. CONCLUSION The recognition of multiple epitopes indicates that the Ro 52-kd antigen itself drives the autoimmunity to this molecule. Further, the concentration of the antigenicity at the leucine zipper region may explain why anti-52-kd antibodies preferentially recognize the denatured protein rather than its native form.
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