Faculty Profiles - akihide Tanimoto

Papers - akihide Tanimoto

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CY Kao, A Tanimoto, N Arima, Y Sasaguri, R Padmanabhan . Transactivation of the human cdc2 promoter by adenovirus E1A - E1A induces the expression and assembly of a heteromeric complex consisting of the CCAAT box binding factor, CBF/NF-Y, and a 110-kDa DNA-binding protein . JOURNAL OF BIOLOGICAL CHEMISTRY274 ( 33 ) 23043 - 23051 1999.8Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC

Cyclin-dependent kinases (CDKs) play an important role in the eukaryotic cell cycle progression. Cdc2 (CDK1) is expressed in late G(1)/S phase and required for G(2) to M phase transition in higher eukaryotes, The oncoproteins, SV40 large T antigen and adenovirus E1A, induce a 110-kDa protein which specifically recognizes the two inverted CCAAT motifs of the cdc2 promoter in cycling cells and plays an essential role in transactivation of the human cdc2 promoter. Since these CCAAT motifs also conform to the consensus binding sites for the ubiquitous heterotrimeric transcription factor, CBF/NF-Y, the role of CBF/NF-Y in the transactivation of the cdc2 promoter was examined in this study. Our results indicate that CBF/NF-Y and the 110-kDa protein interact with the CCAAT box motif to form a heteromeric complex. However, mutagenesis of the pentanucleotide CCAAT motif or in the presence of urea greater than 2.5 M, no heteromeric complex was formed. In contrast, the 110-kDa protein could still bind the mutant CCAAT motif or with the wild type motif in the presence of 2.5 M urea. Furthermore, E1A.12S induced the gene expression of all three subunits of CBF/NF-Y. Coexpression of E1A and a dominant negative mutant NF-YA subunit significantly reduced the E1A-mediated transactivation of the cdc2 promoter in a dose-dependent manner. These results support the conclusion that E1A protein mediates optimal transactivation of the human cdc2 promoter by inducing the expression and assembly of a heteromeric complex consisting of the 110-kDa protein and the CBF/NF-Y which interacts with the two CCAAT motifs of the cdc2 promoter.

DOI： 10.1074/jbc.274.33.23043

S Shimajiri, N Arima, A Tanimoto, Y Murata, T Hamada, KY Wang, Y Sasaguri . Shortened microsatellite d(CA)21 sequence down-regulates promoter activity of matrix metalloproteinase 9 gene . FEBS LETTERS455 ( 1-2 ) 70 - 74 1999.7Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV

One characteristic elements in re promoter of the matrix metalloproteinase 9 (MMP-9) gene is the d(CA) repeat. To investigate whether this element regulates the transcription of the MMP-9 gene and its enzymatic activities, we sequenced the promoter region isolated from esophageal carcinoma cell lines. TE9 cells with low MMP-9 enzymatic activity had the number of d(CA) repeats shortened from 21 to 14 or 18, TE8, TE10 and TE11 cells with high MMP-9 activities had 21 or 23 d(CA) repeats, Luciferase assays using MMP-9 promoter containing 18, 14 or 0 d(CA) repeats showed transcriptional activities which were 50, 50 or 5%, respectively, of the level achieved with promoter containing 21 d(CA) repeats, Sequence analysis of the promoter of 223 Japanese subjects revealed that most had two alleles with 20, 21 or 22 d(CA) repeats, whereas six had one or two alleles with 14, 18 or 19 d(CA) repeats, We postulate that length alteration of the d(CA) repeat causes phenotypic: differences among carcinoma cells and that microsatellite instability may contribute to the polymorphism of d(CA) repeat length, (C) 1999 Federation of European Biochemical Societies.

DOI： 10.1016/S0014-5793(99)00863-7

T Sasaguri, A Tanimoto, N Arima, T Hamada, H Hashimoto, T Sasaguri . Myoepithelioma of soft tissue . PATHOLOGY INTERNATIONAL49 ( 6 ) 571 - 576 1999.6Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：BLACKWELL SCIENCE ASIA

A myoepithelioma occurred in the subcutaneous tissue of the right shoulder of a 28-year-old man. The well-demarcated nodular tumor (3.0 x 2.8 cm) was located in the subcutaneous tissue with no adhesion to the deltoid muscle. The tumor was composed of a fascicular proliferation of spindle cells with variable amounts of stroma and showed areas of Sheets of epithelioid cells, In most areas, the tumor cells had uniform nuclei, but pleomorphic epithelioid cells were focally present. Mitotic activity was three per 10 high-power fields. No ductular structure was found throughout the tumor. Immunohistochemical and ultrastructural studies confirmed the myoepithelial origin of the tumor cells. The occurrence of myoepithelioma in the subcutaneous tissue has been rarely reported. Even though the tumor showed no aggressive behavior on the 2-year followup, it is still too early to comment definitely on the behavior of myoepithelioma of the subcutaneous tissue. This case provides further information about soft tissue myoepithelioma.

DOI： 10.1046/j.1440-1827.1999.00912.x

A Tanimoto, T Hamada, K Higashi, Y Sasaguri . Distribution of cadmium and metallothionein in CdCl2-exposed rat kidney: Relationship with apoptosis and regeneration . PATHOLOGY INTERNATIONAL49 ( 2 ) 125 - 132 1999.2Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY

Male Sprague-Dawley rats were injected subcutaneously with 0.6 mg cadmium/kg bodyweight per day for 6 weeks. In each week of exposure, rats were killed and the localization of cadmium and metallothionein in the kidney was studied by histochemical and immunohistochemical methods. Although cadmium was localized throughout the proximal tubules during exposure, apoptosis and subsequent regeneration were observed mainly in the straight portion of the proximal tubules after 4 weeks of exposure. The distribution of tubular injury may thus not necessarily coincide with that of cadmium. Expression of metallothionein was also detected in the cytoplasm and nuclei of the convoluted and the straight portion of the proximal tubules, but the latter became positive in accordance with apoptosis and regeneration. These results suggest a close relationship between metallothionein distribution and tubular cell regeneration.

DOI： 10.1046/j.1440-1827.1999.00833.x

T Hamada, A Tanimoto, T Sasaguri, N Arima, S Shimajiri, R Nakano, Y Sasaguri . Apoptosis of human kidney 293 cells is promoted by polymerized Cd-metallothionein . METALLOTHIONEIN IV 489 - 495 1999

Publisher：BIRKHAUSER VERLAG AG

Exposure to 12.5 to 37.5 mu M CdCl2 induced apoptosis in transformed human kidney cells (293 cells) as confirmed by characteristic ultrastructural features, a ladder on gel electrophoresis of extracted DNA, and fragmentation of nucleosomes as detected by enzyme linked immunosorbent assay (ELISA). Higher concentrations of Cd were less effective in inducing apoptosis. Furthermore, addition of the protein extract from the serum-free medium used for Cd-exposure promoted apoptosis exhibiting the same features as that after Cd-exposure. The apotosis induced by the protein was dose-dependent. The molecular weight of the protein (Cd-protein) was shown to be 40 kDa by gel filtration. Two-dimensional electrophoresis revealed the Cd-protein as a single spot with a molecular weight of 6 kDa and pI of 4.5. Competitive ELISA showed that the Cd-protein reacted with anti-metallothionein antibody. The present findings suggest that apoptosis is induced not only by Cd itself but also by poly merited metallothionein (MT) molecules released from cells into the medium.

Ying Yan, Ken Higashi, Akihide Tanimoto, Yukiyo Fukamachl, Hideaki Itoh, Tetsuya Abe, Taneaki Higashi . Remarkable difference in the incidence of liver tumors by N- nitrosodimethylamine in carcinogen-resistant DRH rat and its parental strain Donryu rat . Journal of UOEH20 ( 4 ) 307 - 314 1998.12Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：University of Occupational and Environmental Health

The carcinogen-resistant inbred DRH rat strain was developed from the carcinogen-sensitive Donryu rat and showed a remarkably lower incidence of liver tumors than the latter after administration of either 3'-methyl-4- dimethylaminoazobenzene (3'-Me-DAB) or 2-acetylaminofluorene (2-AAF). In the present study, we examined the tolerance of DRH rat to another type of hepatocarcinogen, that is, N-nitrosodimethylamine (DMN). Male DRH and Donryu rats, 3 weeks of age, were given a single i.p. injection of 10 mg/kg body weight DMN and were sacrificed I year later. Five of 11 Donryu rats (45%) had macroscopically detectable tumors: 9 liver tumors in 4 rats and 1 urinary bladder tumor in the other rat. On the contrary, no tumors were detectable in the livers or other organs of 10 DRH rats under the same conditions. These results and other circumstantial evidence indicate that the different susceptibility of chemical carcinogenesis between DRH and Donryu rats is independent of individual pathways of metabolic activation of carcinogens.

DOI： 10.7888/juoeh.20.307

Yan Ying, 東監, 谷本昭英, 深町幸代, 伊藤英明, 安部哲哉, 東胤昭 . N-ニトロソジメチルアミンによる肝癌の発生における発癌耐性DRHラットとその親株呑竜ラットとの間での顕著な差異 . 産業医科大学雑誌20 ( 4 ) 307 - 314 1998.12

Publisher：産業医科大学

近交系の発癌耐性ラット(DRH)は,発癌感受性である呑竜ラットから単離・樹立され,3'-メチル-DABやアセチルアミノフルオレン等による肝癌の発生は著しく抑制されている.上記の肝化学発癌物質とは代謝的活性化の全く異なるN-ニトロソジメチルアミンを用いて両ラットで発癌実験を行った.N-ニトロソジメチルアミンを離乳直後の雄ラットの腹腔内に1回(10mg/kg)投与し,1年後での発癌状態を調べた.11匹の呑竜ラットで5匹に肉眼的に検出できる腫瘍が認められた.4匹の呑竜ラットで9肝癌と,他の1匹では膀胱癌が存在し,病理組織学的にも確認した.これに反し,10匹のDRHラットでは肝及び他の臓器で肉眼的に識別できるような腫瘍は皆無であった

Other Link： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=1998&ichushi_jid=J00526&link_issn=&doc_id=19981211130003&doc_link_id=110001259973&url=http%3A%2F%2Fci.nii.ac.jp%2Fnaid%2F110001259973&type=CiNii&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00003_1.gif

A Tanimoto, H Chen, CY Kao, E Moran, Y Sasaguri, R Padmanabhan . Transactivation of the human cdc2 promoter by adenovirus E1A in cycling cells is mediated by induction of a 110-kDa CCAAT-box-binding factor . ONCOGENE17 ( 24 ) 3103 - 3114 1998.12Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：STOCKTON PRESS

Cyclin-dependent protein kinases (Cdks) are key regulatory proteins of the eukaryotic cell cycle. Cdc2 is expressed in late G1/S phase and functions in the G2 to M phase transition. Adenovirus E1A proteins are known to induce the expression of p34(cdc)2 and DNA synthesis in normal quiescent cells. In this study, mutational analysis of the human cdc2 promoter revealed that transactivation of the promoter by the E1A proteins in cycling cells is mediated through the two CCAAT box binding motifs. A 110-kDa protein (CBF/cdc2) was identified in nuclear extracts from monkey kidney (CV-1) cells stably expressing E1A as well as from adenovirus-transformed human 293 cells, Further, we show that this E1A-inducible CBF/cdc2 is related to the CBF which was shown to activate the heat shock protein 70 promoter. Analyses of the functional domain(s) of E1A required for the induction of the CBF and transactivation of the cdc2 promoter in these conditions revealed that E1A mutants which were defective in binding the pRB family of proteins or the cellular p300 protein were still active in assays measuring the induction of the CBF and transactivation of the cdc2 promoter, albeit with reduced efficiencies. But the E1A mutant which lost both functional domains was inactive in these assays. These results suggest that E1A has redundant functional domains for the induction of the 110-kDa CBF and activation of human cdc2 gene expression.

DOI： 10.1038/sj.onc.1202236

A Tanimoto, CY Kao, CC Chang, Y Sasaguri, R Padmanabhan . Deregulation of cdc2 gene expression correlates with overexpression of a 110 kDa CCAAT box binding factor in transformed cells . CARCINOGENESIS19 ( 10 ) 1735 - 1741 1998.10Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：OXFORD UNIV PRESS

Eukaryotic cell cycle progression is regulated by an orderly and sequential activation of several cyclin-dependent kinases, which phosphorylate key substrates during this process. p34(cdc2), the catalytic subunit of cdc2 kinase, is expressed at the late G(1)/S boundary and is required for the G(2)-->M phase transition. Transactivation of the human cdc2 promoter by the DNA tumor virus-encoded oncogenic protein SV40 large T antigen is mediated by induction of a novel 110 kDa CCAAT box binding factor (CBF/cdc2), To investigate whether induction of CBF/cdc2 is an intrinsic property of the viral oncoprotein or is a common event during transformation of normal cells, expression of CBF/cdc2 was analyzed in many human tumor cell lines and in rodent cells spontaneously transformed or stably expressing various oncogenes, Our results showed that CBF/cdc2 was overexpressed in all transformed cells examined, including human 293, MCF-7, HeLa and HepG2 cells. Moreover, expression of CBF/cdc2 was elevated in spontaneously transformed rat liver epithelial cells (C4T), but not detectable in the non-tumorigenic parental (RLE) cells. The elevated levels of CBF/cdc2 expression in C4T cells correlated well with increased cdc2 mRNA and p34(cdc2) levels. CBF/cdc2 was also overexpressed in a rat liver epithelial cell line (WB) stably transfected with various oncogenes, v-myc, v-Ha-ras and mutated rat neu and v-src, Using an electrophoretic mobility shift assay, specific binding of CBF/cdc2 to the CCAAT box motifs of the human cdc2, cycA and cdc25C promoters was detected, suggesting that transcription of these cell cycle regulatory genes are coordinately activated by CBF/cdc2.

DOI： 10.1093/carcin/19.10.1735

T Hamada, A Tanimoto, N Arima, Y Ide, T Sasaguri, S Shimajiri, Y Sasaguri . Altered membrane skeleton of red blood cells participates in cadmium-induced anemia . BIOCHEMISTRY AND MOLECULAR BIOLOGY INTERNATIONAL45 ( 4 ) 841 - 847 1998.7Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：ACADEMIC PRESS AUST

Poikilocytosis of red blood cells (RBCs) was observed to be associated with anemia in rats given subcutaneous injections of cadmium (Cd). Phase-contrast light and scanning electron microscopic examinations revealed that acanthocytes appeared in the early stages of administration, and that the number of RBC fragments increased later. Ultrastructural analysis of RBC ghosts by negative staining demonstrated that the normal lattice structure of the membrane skeleton was abolished. The osmotic fragility curve of the Cd-exposed RBCs disclosed that most of the cells were less fragile than control RBCs. These data indicate that the RBC membrane skeleton is initially altered by Cd-exposure, followed by deformation of the cell, thus promoting intrasplenic hemolysis, and resulting in anemia.

Nishigaki, I, A Tanimoto, Y Sasaguri, K Yagi . Glycated protein-iron chelate increases lipid peroxide level in cultured aortic endothelial and smooth muscle cells . BIOCHEMISTRY AND MOLECULAR BIOLOGY INTERNATIONAL45 ( 3 ) 519 - 526 1998.7Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：ACADEMIC PRESS AUST

Formation of an iron chelate of glycated protein was demonstrated by the appearance of an absorption peak at approximately 270 nm after mixing glycated bovine serum albumin with FeCl3. This peak disappeared and a new peak appeared at approximately 420 nm to form an isosbestic point at approximately 340 nm by the addition of deferoxamine mesylate, an iron-chelating agent, to the mixture, thus confirming the formation of the iron chelate of the glycated protein in the mixture. The lipid peroxide level was increased markedly in endothelial cells and slightly in smooth muscle cells from bovine aorta incubated in the medium containing glycated fetal bovine serum-iron chelate. Morphological observation by phase-contrast microscopy and scanning electron microscopy revealed that the glycated fetal bovine serum-iron chelate caused intense damage to the endothelial cells. These results indicate that glycated protein-iron chelate provokes lipid peroxidation, which explains at least in part the mechanism of atherogenesis found in diabetic patients.

T Sasaguri, N Arima, A Tanimoto, S Shimajiri, T Hamada, Y Sasaguri . A role for interleukin 4 in production of matrix metalloproteinase 1 by human aortic smooth muscle cells . ATHEROSCLEROSIS138 ( 2 ) 247 - 253 1998.6Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI IRELAND LTD

Effect of interleukin 4 (IL-4) on the production of matrix metalloproteinase 1 (MMP-1) by normal and immortalized human intimal smooth muscle cells (SMC) was investigated. The production of the precursors of MMP-1 by intimal SMC was enhanced in a dose-dependent manner by addition of IL-4 to the culture medium, whereas the cytokine also showed an inhibitory effect on DNA synthesis in the cells. In addition, mRNA of IL-4 was found in the atherosclerotic and nonatherosclerotic areas of the intima. Although the production of MMP-1 and the proliferation of SMC are thought to play an important role in reconstruction of the intima during atherogenesis, our results suggest a possible role of IL-4 induced MMP-1 in inhibiting tissue remodeling caused by a variety of arterial disorders including atherosclerosis. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.

DOI： 10.1016/S0021-9150(97)00296-7

M Kato, A Tanimoto, N Arima, M Morimatsu, Y Sasaguri . Response to platelet-derived growth factor by phenotypically different cultured human aortic smooth muscle cells . BIOCHEMISTRY AND MOLECULAR BIOLOGY INTERNATIONAL44 ( 4 ) 815 - 823 1998.4Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：ACADEMIC PRESS AUST

We investigated the effects of PDGF on DNA synthesis and mitogen-activated protein (MAP) kinase activity, and demonstrated that the adult intimal SMC was concentration-dependently stimulated by all PDGF isoforms in terms of both [H-3]thymidine incorporation and MAP kinase activation, with PDGF-BB and -AB being more potent than PDGF-AA. The intimal SMCs and the neonatal SMCs showed a similar response with regard to MAP kinase activation. On the other hand, the intimal SMCs expressed many more PDGF receptors than the adult medial SMCs, which expressed a greater amount of PDGF-A chain mRNA and showed a lesser response to PDGFs. These results suggest that the intimal SMCs have a relatively high potential to react to exogenous PDGFs, whereas the adult medial SMCs depend on endogenous or autocrine secretion of PDGF-AA.

Tetsuo Hamada, Akihide Tanimoto, Nobuyuki Arima, Yoshihiro Ide, Takakazu Sasaguri, Shohei Shimajiri, Yoshitaka Murata, Ke-Yong Wang, Yasuyuki Sasaguri . Pathological study of splenomegaly associated with cadmium-induced anemia in rats . Journal of UOEH20 ( 1 ) 11 - 19 1998.3Reviewed

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：University of Occupational and Environmental Health

Splenomegaly was observed both in male and female Sprague-Dawley rats after 1 week of exposure to CdCl2 (0.6 mg Cd/kg/day). Spleen weight reached about double that in controls by 8 weeks of Cd exposure. Histopathological examination of the enlarged spleen revealed that iron- and lipid-laden histiocytes were clustered in the periarterial lymphatic sheath, and the red pulp appeared to be expanded. It is noteworthy that electron microscopy revealed marked poikilocytosis and Heinz body formation in red blood cells (RBCs) in both the sinus and cord. Histiocytes were swollen by a granular substance in the cytoplasm and also many secondary lysosomes. These morphological findings indicate that degradation of damaged RBCs induced by exposure to Cd might be promoted in the spleen and possibly cause splenomegaly. This RBC damage-hemolysis-splenomegaly sequence is also considered to be associated with the etiology of Cd-induced anemia. In addition to the abnormal RBC degradation, nuclei of lymphocytes in the Cd- exposed spleen exhibited high electron density, consistent with a preapoptotic state suggesting the immunosuppressive effect of Cd.

DOI： 10.7888/juoeh.20.11

濱田哲夫, 谷本昭英, 有馬信之 . カドミウム誘発貧血症ラットにおける脾腫の病理学的研究 . 産業医科大学雑誌20 ( 1 ) 11 - 19 1998.3

Publisher：産業医科大学

Cd誘発貧血症の発症機序について検討した.ラットでは脾腫はCdの慢性投与により,1週間後には明らかとなり,その重量は8週間では対照の約2倍となった.腫大脾の電子顕微鏡的検索ではハインツ小体(HB)の形成と著明なPCが目立った.Cdは初めに赤血球膜異常ついでPC増多症を引き起こし,この異常赤血球が脾で処理されるため皮腫が招来されることが示された

Other Link： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=1998&ichushi_jid=J00526&link_issn=&doc_id=19980313300002&doc_link_id=110001261427&url=http%3A%2F%2Fci.nii.ac.jp%2Fnaid%2F110001261427&type=CiNii&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00003_1.gif

Y Ide, A Tanimoto, Y Sasaguri, R Padmanabhan . Hepatitis C virus NS5A protein is phosphorylated in vitro by a stably bound protein kinase from HeLa cells and by cAMP-dependent protein kinase A-alpha catalytic subunit . GENE201 ( 1-2 ) 151 - 158 1997.11Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCIENCE BV

Hepatitis C virus (HCV) has a positive-strand RNA genome that codes for a polyprotein precursor, which is processed co-and post-translationally by cellular and viral proteinases into three structural and at least six non-structural (NS) proteins. The NS5A protein, expressed in mammalian cells, exists in two phosphorylated forms of 56-kDa and 58-kDa. In this study, we provide evidence for a stable association between NS5A and a protein kinase from HeLa cells and hepatocellular carcinoma (HepG2) cells by co-immunoprecipitation and by affinity to immobilized glutathione-S-transferase (GST)-NS5A fusion protein produced in E. coli. This protein kinase could phosphorylate in vitro the native NS5A on serine residues, (GST)-NS5A, histone H1, and casein as substrates. In addition, the GST-NS5A was also phosphorylated in vitro by the cAMP-dependent protein kinase A-alpha catalytic subunit. (C) 1997 Elsevier Science B.V.

DOI： 10.1016/S0378-1119(97)00440-X

T Hamada, A Tanimoto, Y Sasaguri . Apoptosis induced by cadmium . APOPTOSIS2 ( 4 ) 359 - 367 1997.8Invited Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：RAPID SCIENCE PUBLISHERS

Cell death resulting from cadmium (Cd) intoxication has been confirmed to occur through apoptosis by morphological and biochemical studies, However it is still not clear whether Cd itself or metallothionein (MT) induced by Cd is the major factor responsible for the apoptosis, Although apoptosis is inducible by exposure of cells to various stimuli, the common pathway involved is generally accepted to be activation of endonucleases that induce internucleosomal cleavage of DNA, resulting in the 'ladder' formation observed upon agarose gel electrophoresis and the chromatin condensation seen by electron microscopy. Cd does not seem to activate the endonuclease in vitro. However, Cd itself can be associated with apoptosis through indirect oxidative stress by inhibition of antioxidant enzymes and possible interaction with zinc finger protein, In addition to the direct effect of Cd, MT appears to play dual roles in apoptosis induction: one as a Cd carrier by which Cd accumulates in the nucleus, and the other as an inhibitor of zinc finger proteins, which include transcriptional factors related to apoptosis such as the product of the apoptosis resistance gene A20. In this review, we demonstrated that the mode of cell death following Cd exposure is associated with intracellular movement of Cd and MT. A possible mechanism for Cd-induced apoptosis is also discussed.

A Tanimoto, Y Ide, N Arima, Y Sasaguri, R Padmanabhan . The amino terminal deletion mutants of hepatitis C virus nonstructural protein NS5A function as transcriptional activators in yeast . BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS236 ( 2 ) 360 - 364 1997.7Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS

To investigate the biological function of hepatitis C virus (HCV)-NS5A, the NS5A was fused at its N-terminus with the DNA binding domain (DBD) of yeast transcriptional activator GAL4 (GAL4-DBD). The GAL4-DBD alone had no transcriptional activation function. However, a mutant of the GAL4-DBD/NS5A fusion protein, in which 129 amino acid residues were deleted from the N-terminus of NS5A, exhibited strong transcriptional activation in yeast cells, bearing the Escherichia coli lacZ reporter gene encoding the beta-galactosidase under the transcriptional control of GAL4 promoter and TATA box. Further mutational analysis of NS5A revealed that the region between the amino acid residues 130 to 352 were critical for optimal level of transactivation. This region includes two acidic domains and one proline-rich region which have been shown to be involved in the function of several transcriptional activators. (C) 1997 Academic Press.

DOI： 10.1006/bbrc.1997.6967

N Arima, Shima, I, S Shimajiri, Y Sasaguri, T Sasaguri, A Tanimoto, T Hamada, M Morimatsu . Phenotypes of human esophageal squamous cell carcinoma based on matrix metalloproteinase production . INTERNATIONAL JOURNAL OF ONCOLOGY10 ( 2 ) 269 - 277 1997.2Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：INT JOURNAL ONCOLOGY

We investigated the effects of epidermal growth factor (EGF) and transforming growth factor-beta (TGF-beta) on cell growth and on regulation of matrix metalloproteinases (MMPs) in four cell lines of human esophageal squamous cell carcinomas (TE8, TE9, TE10, and TE11). EGF stimulated the production of proforms of gelatinase B (MMP-9) by three cell lines that could synthesize EGF by themselves, with TE9 being the exception. Particularly, both the production of MMP-9 and DNA synthesis in TE10 were stimulated significantly by EGF. TGF-beta slightly stimulated DNA synthesis in two cell lines, TE9 and TE11, and TGF-beta secretion by TE9 was detected. The production of proforms of gelatinases A (MMP-2) and MMP-9 was gradually induced by TGF-beta in a concentration-dependent manner in all the cell lines except for TE9. Flow cytometric analysis revealed that all the lines expressed both EGF- and TGF-beta-receptors. In conclusion, our present results indicate that at least there are possibly two distinct phenotypes in human esophageal squamous cell carcinoma: one (TE10) depends on autocrine EGF production that enhances DNA synthesis and MMP-9 production; and the other (TE9) on autocrine TGF-beta that stimulates DNA synthesis but not in relation to gelatinase production.

T Tanaka, K Hara, A Tanimoto, K Kasai, T Kita, N Tanaka, T Takayasu . Determination of arsenic in blood and stomach contents by inductively coupled plasma/mass spectrometry (ICP/MS) . FORENSIC SCIENCE INTERNATIONAL81 ( 1 ) 43 - 50 1996.7Reviewed

Language：English Publishing type：Research paper (scientific journal) Publisher：ELSEVIER SCI IRELAND LTD

Inductively coupled plasma/mass spectrometry (ICP/MS) was used and evaluated for the practical analysis of the arsenic content of body fluid samples without ashing. The calibration curve for arsenic in blood solution was shown to have good sensitivity, linearity and reproducibility. Blood obtained from normal volunteers was determined by ICP/MS, and compared with that determined by atomic absorption spectrometry (AAS). The arsenic contents determined by ICP/MS showed a linear correlation with that determined by AAS. Furthermore, arsenic was determined in the blood and supernatant of stomach contents obtained from a suicide autopsy case resulting from ingestion of an arsenic compound. It was therefore concluded that ICP/MS could be used rapidly and conveniently in the field of forensic toxicology in acute metal poisoning cases.

DOI： 10.1016/0379-0738(96)01942-1

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