158 results on '"Takatoshi Ishikawa"'
Search Results
2. Syndromic surveillance using ambulance transfer data in Tokyo, Japan
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Takatoshi Ishikawa, Yoshiyuki Sugishita, Michihiko Yoshida, Yasushi Ohkusa, Hiroyoshi Endo, and Tamie Sugawara
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0301 basic medicine ,Microbiology (medical) ,medicine.medical_specialty ,Metropolitan government ,Ambulances ,030106 microbiology ,Disaster Planning ,Communicable Diseases ,Disease Outbreaks ,Foodborne Diseases ,03 medical and health sciences ,0302 clinical medicine ,Mass gathering ,medicine ,Humans ,Pharmacology (medical) ,030212 general & internal medicine ,Tokyo ,business.industry ,Public health ,Outbreak ,medicine.disease ,Bioterrorism ,Metropolitan area ,Infectious Diseases ,Models, Organizational ,Medical emergency ,Nasal Hemorrhage ,business ,Sentinel Surveillance - Abstract
Bioterrorism attacks become more probable when important high-profile international or political events are held, such as G7 summit meetings or mass gathering events including Olympic and Paralympic games and FIFA World Cup tournaments. Outbreaks of infectious disease and widespread incidents of food poisoning are also public health concerns at such times. In Japan, the Tokyo Metropolitan Government operates Ambulance Transfer Syndromic Surveillance (ATSS), which can help monitor such incidents. The present study presents and assesses the ATSS framework. During the study period of October 2017 through November 2018, we monitored 33 areas for symptoms of 9 categories: vomiting/nausea, dizziness, palpitation, unconsciousness, breathing disorder, fever, spasm/paralysis, collapse/weakness, and bloody emesis/nasal hemorrhage. Among all symptoms, we found 9929 low-level aberrations, 2537 medium-level aberrations, and 577 high-level aberrations, with respective frequencies of 9.2%, 2.3%, and 0.5%. Of those, Tokyo Metropolitan Institute of Public Health reported the information to Tokyo Metropolitan Government 28 times during the period. Of the 28 identified clusters, Tokyo Metropolitan Government judged the necessity for investigating 7. All of those were investigated at hospitals by the jurisdictional public health center. Because ATSS covers almost the entire Tokyo metropolitan area, with about 13.8 million residents, it is definitely the largest syndromic surveillance in the world.
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- 2020
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3. Clinical significance of the Siaα2,3gal-glycosylated prostate-specific antigen assay for prostate cancer detection
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Kazuyuki Mori, M. Sutoh Yoneyama, Jehonathan H. Pinthus, M. Date, Robert A. Gardiner, Chikara Ohyama, Tohru Yoneyama, Teppei Okubo, Yuki Tobisawa, Shingo Hatakeyama, Koji Mitsuzuka, Akihiro Ito, Takuya Koie, Takatoshi Ishikawa, Yasuhiro Hashimoto, and Wilhelmina C.M. Duivenvoorden
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Prostate cancer ,business.industry ,Urology ,Prostate Specific Antigen Assay ,Cancer research ,Medicine ,Clinical significance ,business ,medicine.disease ,lcsh:Diseases of the genitourinary system. Urology ,lcsh:RC870-923 ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,lcsh:RC254-282 - Published
- 2020
4. The Handbook of Experimental Animals
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Peter, Petrusz, primary, Gillian, Bullock, additional, Linda J, Lowenstine, additional, Linda C, Cork, additional, Katsuhiko, Arai, additional, Prince, Masahito, additional, David, Buist, additional, Stephen W, Barthold, additional, Takatoshi, Ishikawa, additional, Michael, Sinosich, additional, Paul, Herrling, additional, Sonia, Wolfe-Coote, additional, and Maurice, Cary, additional
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- 2005
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5. O6-methylguanine-DNA methyltransferase protects against nitrosamine-induced hepatocarcinogenesis
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Yoko Nakatsuru, Shoichi Matsukuma, Nobuo Nemoto, Haruo Sugano, Mutsuo Sekiguchi, and Takatoshi Ishikawa
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Liver cancer -- Research ,Science and technology - Abstract
The liver carcinogenesis in transgenic C3H/HeN mice, produced by introducing the Escherichia coli O6-methylguanine-DNA methyltransferase (MGMT, DNA-O6-methylguanine:-protein-L-cysteine S-methyltransferase, EC2.1.1.63) gene, ada, linked to the Chinese hamster metallothionein I gene pronoter and exhibiting large amounts of MGMT, was analyzed to find whether the higher levels of MGMT activity can reduce vulnerability of animals to N-nitroso compounds. MGMT can safeguard animals against low-dose exposure, environmental alkylating carcinogens.
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- 1993
6. 3D Stacking Process with Thermo-Sonic Bonding Using Non-conductive Film
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Takatoshi Ishikawa, Naoki Kanagawa, Teppei Kojio, Kazuki Watanabe, and Yamatsu Shigeru
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Viscosity ,Materials science ,Silicon ,chemistry ,Through-silicon via ,Delamination ,Thermal ,Stacking ,chemistry.chemical_element ,Composite material ,Electrical conductor ,Throughput (business) - Abstract
In this research, a combination of thermo-sonic bonding (TSB) process and non-conductive film (NCF) material was used to fabricate vertically stacked through silicon via (TSV) assemblies. TSB is particularly attractive TSV assembly process because it offers up to 10x throughput improvement when compared to conventional processes. By adjusting the properties (e.g. viscosity, and reaction time) of NCF, a 4-layer stacked assembly was fabricated without voids or delamination. Moreover, these parts exhibited no failures after 2,000 times thermal cycles test (-40oC to 125oC).
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- 2018
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7. Development of High Productive Micro Solder Flip Chip Bonding Process
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Takashi Nakamura, Takatoshi Ishikawa, Daisuke Sakurai, Takatoshi Osumi, and Kazuya Ushirokawa
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Bonding process ,Materials science ,Soldering ,Nanotechnology ,Flip chip - Published
- 2012
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8. Two new actions of sea nettle (Chrysaora quinquecirrha) nematocyst venom: studies on the mechanism of actions on complement activation and on the central nervous system
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Abulkalam M. Shamsuddin, Takatoshi Ishikawa, Joseph W. Burnett, Ivana Vucenik, and Florin Niculescu
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Jellyfish ,Central nervous system ,Venom ,In Vitro Techniques ,Pharmacology ,Administration, Cutaneous ,Toxicology ,Chrysaora quinquecirrha ,Lethal Dose 50 ,Cyprinodontiformes ,03 medical and health sciences ,Cnidarian Venoms ,biology.animal ,medicine ,Animals ,Humans ,Killifish ,Nematocyst ,Complement Activation ,030304 developmental biology ,0303 health sciences ,biology ,030302 biochemistry & molecular biology ,Brain ,Sea Nettle, East Coast ,Anatomy ,biology.organism_classification ,Epithelium ,Complement system ,medicine.anatomical_structure ,Rabbits - Abstract
Chrysaora quinquecirrha (sea nettle) nematocyst venom is lethal to rainbow killifish (Adina xenica) when injected intraperitoneally or topically applied to the exposed brain or denuded epithelium. The lethal activity is thermostable requiring 100 degrees C heat for inactivation. This paper reports here for the first time that the venom also activates the complement system with the subsequent formation of the C5b-9 terminal complement complex. The events are associated with both a strong chemoattractant release and the tissue damage. These are also, at least in part, responsible for the pathogenesis of some clinical signs and symptoms associated to the jellyfish stings.
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- 2004
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9. Skin and salivary gland carcinogenicity of 7,12-dimethylbenz[a]anthracene is equivalent in the presence or absence of aryl hydrocarbon receptor
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Takatoshi Ishikawa, Kaoru Kusama, Fumio Ide, Munenori Kitada, Noriyuki Suka, and Hideaki Sakashita
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endocrine system ,Cancer Research ,Skin Neoplasms ,CYP1B1 ,DMBA ,Mice ,chemistry.chemical_compound ,Cytochrome P-450 CYP1A2 ,Benz(a)Anthracenes ,polycyclic compounds ,medicine ,Animals ,Humans ,RNA, Messenger ,skin and connective tissue diseases ,Epoxide hydrolase ,Carcinogen ,biology ,Gene Expression Profiling ,7,12-Dimethylbenz[a]anthracene ,Neoplasms, Experimental ,respiratory system ,Salivary Gland Neoplasms ,Aryl hydrocarbon receptor ,Submandibular gland ,Molecular biology ,respiratory tract diseases ,Mice, Inbred C57BL ,Cell Transformation, Neoplastic ,medicine.anatomical_structure ,Receptors, Aryl Hydrocarbon ,Oncology ,chemistry ,Biochemistry ,Microsomal epoxide hydrolase ,Cytochrome P-450 CYP1B1 ,biology.protein ,Female ,Aryl Hydrocarbon Hydroxylases - Abstract
7,12-Dimethylbenz[a]anthracene (DMBA) is a well-known polycyclic aromatic hydrocarbon (PAH) that causes a variety of tumors in exposed animals. Although PAH carcinogenicity is primarily mediated by the aryl hydrocarbon receptor (AhR) through induction of P450, it is not precisely determined whether AhR regulates the DMBA carcinogenesis in vivo. In this context, we examined the frequency of DMBA-induced tumors and the expressions of mRNAs of P450-CYP1 subfamily and microsomal epoxide hydrolase (mEH) in the skin and submandibular gland using AhR-deficient mice. After DMBA exposure, AhR−/− and AhR+/+ mice showed the same tumor incidences and latency. CYP1A1 was absent in these tissues but was slightly induced in DMBA-treated AhR+/+ mice. In AhR−/− and AhR+/+ mice, constitutive expression of CYP1B1 was evident at equivalent levels, whereas CYP1A2 was not detectable, irrespective of DMBA treatment. mEH was expressed in both tissues of all animals. Collectively, the constitutive levels of CYP1B1 and mEH in the skin and submandibular gland maintain DMBA response in these tissues of AhR−/− mice.
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- 2004
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10. DNA repair and cancer: Lessons from mutant mouse models
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Xiusheng Qin, Samuel Shao Min Zhang, Yoko Nakatsuru, Hideaki Oda, Fumio Ide, Yoshihisa Takahashi, and Takatoshi Ishikawa
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Cancer Research ,Xeroderma pigmentosum ,DNA Repair ,DNA repair ,DNA damage ,Biology ,medicine.disease_cause ,Cancer syndrome ,Mice ,O(6)-Methylguanine-DNA Methyltransferase ,Neoplasms ,medicine ,Animals ,Humans ,Cancer epigenetics ,Genetics ,O-6-methylguanine-DNA methyltransferase ,General Medicine ,Genes, p53 ,medicine.disease ,Mice, Mutant Strains ,Xeroderma Pigmentosum Group A Protein ,DNA-Binding Proteins ,Disease Models, Animal ,Oncology ,Mutation ,Cancer research ,Carcinogenesis ,Nucleotide excision repair - Abstract
DNA damage, if the repair process, especially nucleotide excision repair (NER), is compromised or the lesion is repaired by some other error-prone mechanism, causes mutation and ultimately contributes to neoplastic transformation. Impairment of components of the DNA damage response pathway (e.g., p53) is also implicated in carcinogenesis. We currently have considerable knowledge of the role of DNA repair genes as tumor suppressors, both clinically and experimentally. The deleterious clinical consequences of inherited defects in DNA repair system are apparent from several human cancer predisposition syndromes (e.g., NER-compromised xeroderma pigmentosum [XP] and p53-deficient Li-Fraumeni syndrome). However, experimental studies to support the clinical evidence are hampered by the lack of powerful animal models. Here, we review in vivo experimental data suggesting the protective function of DNA repair machinery in chemical carcinogenesis. We specifically focus on the three DNA repair genes, O(6)-methylguanine-DNA methyltransferase gene (MGMT ), XP group A gene (XPA) and p53. First, mice overexpressing MGMT display substantial resistance to nitrosamine-induced hepatocarcinogenesis. In addition, a reduction of spontaneous liver tumors and longer survival times were evident. However, there are no known mutations in the human MGMT and therefore no associated cancer syndrome. Secondly, XPA mutant mice are indeed prone to spontaneous and carcinogen-induced tumorigenesis in internal organs (which are not exposed to sunlight). The concomitant loss of p53 resulted in accelerated onset of carcinogenesis. Finally, p53 null mice are predisposed to brain tumors upon transplacental exposure to a carcinogen. Accumulated evidence in these three mutant mouse models firmly supports the notion that the DNA repair system is vital for protection against cancer.
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- 2004
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11. Development of Bioreactor for Fe (III) EDTA Chelate Degradation Processing in the Industrial Wastewater-Immobilizations of Fe (III) EDTA Chelate-Degrading Bacteria and Their Degrading Behaviors
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Sadaaki Murakami, Emiko Shinagawa, Mitsuaki Tamura, Kimitoshi Fukunaga, Hideo Miyazaki, Hirohito Yamasaki, and Takatoshi Ishikawa
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Industrial wastewater treatment ,biology ,Chemistry ,Inorganic chemistry ,Bioreactor ,Degradation (geology) ,Chelation ,biology.organism_classification ,Fe(III)-EDTA ,Bacteria - Abstract
EDTA鉄 (III) キレートを効率よく分解する細菌としてBacillus sp. B-3を用いたバイオリアクターを開発しているが, 本研究ではその固定化菌体について検討した.固定化法としては, 安価で容易に固定化できる物理的吸着法と包括法を試みた.固定化担体には, 既製品であるセルロース球状担体 (SC) , ポリプロピレンを基材とする円筒状担体 (CPP) , 高分子ヒドロゲル (SHG) , 及び光硬化性プレポリマーENTGによって菌体を包括した包括固定化担体を用いた.栄養源としてポリペプトン及び酵母エキスを含む培地で, 初濃度100mg/lのFe (III) EDTAの分解試験を行ったところ, SC, CPP及びSHGに吸着固定化した菌体, 及び光硬化性プレポリマーに包括固定化した菌体は7日間でそれぞれ79%, 73%, 71%, 84%のEDTAを分解したが, 栄養源を含まない培地では, いずれの菌体もEDTAを分解できなかった.SCに吸着固定化した菌体で7日間の分解試験を行った後, 同じ試験を繰り返し4回行ったが, 固定化菌体の分解能に低下は見られなかった (繰り返しの分解能の誤差±5.6%以内) .また, 90日間の常温保存後の固定化菌体のEDTA分解能に低下は認められなかった.
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- 2004
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12. Dibenzo[A,L]pyrene-induced genotoxic and carcinogenic responses are dramatically suppressed in aryl hydrocarbon receptor-deficient mice
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Yoko Nakatsuru, Fumio Ide, Kaoru Kusama, Yoshiaki Fujii-Kuriyama, Takatoshi Ishikawa, and Keiji Wakabayashi
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Male ,Cancer Research ,Skin Neoplasms ,Genotype ,CYP1B1 ,Administration, Cutaneous ,medicine.disease_cause ,Toxicology ,DNA Adducts ,Mice ,medicine ,Animals ,Neoplastic transformation ,Benzopyrenes ,Carcinogen ,Mice, Knockout ,Carcinogenic Polycyclic Aromatic Hydrocarbon ,biology ,Chemistry ,Cytochrome P450 ,respiratory system ,Aryl hydrocarbon receptor ,Molecular biology ,respiratory tract diseases ,Cell Transformation, Neoplastic ,Receptors, Aryl Hydrocarbon ,Oncology ,Carcinogens ,biology.protein ,Female ,Carcinogenesis ,Genotoxicity - Abstract
Dibenzo[a,l]pyrene (DB[a,l]P), a notorious air pollutant, is the most powerful carcinogenic polycyclic aromatic hydrocarbon (PAH) ever tested. Although the carcinogenicity of PAH may be primarily mediated by the aryl hydrocarbon receptor (AhR), the in vivo role of AhR in skin carcinogenesis remains to be defined. In this context, we investigated the genotoxic and carcinogenic responses of the AhR-deficient mouse skin to DB[a,l]P. A single painting resulted in a striking epidermal hyperplasia in AhR+/+ mice but not in AhR−/− mice. Bromodeoxyuridine-labeling index and accumulation of p53 protein in epidermal cells of AhR+/+ mice were 8- and 33-fold higher than those of AhR−/− mice, respectively. 32P-Postlabeling assay for DB[a,l]P-DNA adducts displayed a 2-fold increase in the AhR+/+ mouse skin. After DB[a,l]P exposure, AhR−/− mice arranged a nearly 60% reduction in the induction of epidermal cytochrome P450 (CYP)1A1, but CYP1B1 was constitutively expressed in both genotypes of mice, irrespective of DB[a,l]P treatment. As compared with AhR+/+ mice, AhR−/− mice had both significantly lower incidence (100% vs. 33%) and multiplicity (2.7 vs. 0.46) of skin tumors by the complete carcinogenesis study. These observations indicate that a reduced tumor yield in AhR−/− mice may be secondary to reduction of inducible CYP1A1 activation and subsequent DNA adduction. It is evident from our continuous work that although AhR is likely to play a central role in epidermal proliferation and possibly neoplastic transformation, the relative importance of AhR for carcinogenesis may be different among PAH examined. © 2004 Wiley-Liss, Inc.
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- 2004
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13. Control of Hospital Infection of Influenza: Administration of Neuraminidase Inhibitor and Cohort Isolation of Influenza Patients
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Megumi Annaka, Hiroshi Higuchi, Takatoshi Ishikawa, Yoriko Kosugi, Yoshishige Masuda, Yuri Chimura, Takashi Inamatsu, Sumie Shibazaki, Keiko Adachi, Kenji Sadamasu, and Takayuki Shinkai
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Male ,medicine.medical_specialty ,Oseltamivir ,Isolation (health care) ,medicine.drug_class ,Antibiotics ,Neuraminidase ,Antiviral Agents ,Disease Outbreaks ,Patient Isolation ,chemistry.chemical_compound ,Internal medicine ,Acetamides ,Influenza, Human ,medicine ,Humans ,Viral shedding ,Nose ,Aged ,Cross Infection ,Rapid diagnostic test ,Neuraminidase inhibitor ,business.industry ,General Medicine ,medicine.anatomical_structure ,chemistry ,Immunology ,Cohort ,Female ,business - Abstract
Influenza can spread rapidly to patients and staff in hospitals when influenza is introduced by visitors, staff, or patients. In order to prevent and control outbreaks of influenza in hospitals, systematic management is important. This consists of a rapid diagnostic test, cohort isolation and administration of neuraminidase inhibitor. In the 2002-2003 season, 53 elderly patients were admitted to our hospital under the control of the system. The mean age was 78.8 years. We set 2 isolation rooms (10 beds) for influenza patients. Patients were isolated in the room for three days, administered oseltamivir immediately. Oral oseltamivir was well tolerated. Mean hospital stay was 10.7 days. 36 cases developed complications requiring antibiotics, and one patient developed a catheter related infection. Under the system, we could avoid cross infection of influenza. In two cases, nose swabs were taken for virus isolation every 12 hours and a rapid decline in virus shedding was observed after treatment.
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- 2004
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14. Effects of rabeprazole, lansoprazole and omeprazole on intragastric pH in CYP2C19 extensive metabolizers
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Takatoshi Ishikawa, Yasushi Fukushima, J. Hirakawa, K. Ogawa, Toshihito Saitoh, T. Katsube, Hidetoshi Mori, H. Otsuka, S. Ohkawa, and Tomoichiro Asano
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Hepatology ,business.industry ,medicine.drug_class ,Stomach ,Gastroenterology ,Rabeprazole ,Lansoprazole ,Proton-pump inhibitor ,CYP2C19 ,Pharmacology ,Crossover study ,medicine.anatomical_structure ,Medicine ,Gastric acid ,Pharmacology (medical) ,business ,Omeprazole ,medicine.drug - Abstract
Summary Aim : To investigate the inhibitory effects on gastric acid secretion of three proton pump inhibitors, omeprazole, lansoprazole and rabeprazole, using a three-way crossover design in healthy Helicobacter pylori-negative,S-mephenytoin 4′-hydroxylase (CYP2C19) homo- and hetero-extensive metabolizers. Methods : Eight healthy Japanese male volunteers were enrolled. After the administration of rabeprazole (10 mg/day), lansoprazole (30 mg/day) or omeprazole (20 mg/day), intragastric pH monitoring was commenced from 24 h before the first proton pump inhibitor dose, and continued for days 1–3 after proton pump inhibitor administration. The pH electrode was used for 48 h and changed just before pH monitoring on day 2. Results : For the administration of 10 mg/day rabeprazole, the mean ratios of the 24-h pH ≥ 3 holding timewere 5.7 ± 1.1%,13.6 ± 2.2%, 35.3 ± 2.7% and 62.8 ± 3.1% for the pre-treatment day and days 1, 2 and 3, respectively. The same ratios for lansoprazole (30 mg/day) were 5.7 ± 0.7%, 7.4 ± 1.5%, 13.6 ± 3.4% and 26.6 ± 4.9%; the same ratios for 20 mg/day omeprazole were 5.9 ± 0.9%, 6.1 ± 1.2%, 11.4 ± 2.8% and 16.4 ± 4.6%. The mean ratio of the 24-h pH ≥ 3 holding time of days 1–3 increased significantly compared to the pre-treatment day (P
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- 2002
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15. Enhanced spontaneous and aflatoxin-induced liver tumorigenesis in xeroderma pigmentosum group A gene-deficient mice
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Haruki Kume, Yasuhito Shimizu, Shaomin Zhang, Yoshihisa Takahashi, Kiyoji Tanaka, Takatoshi Ishikawa, Fumio Ide, and Yoko Nakatsuru
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Male ,Heterozygote ,Cancer Research ,Pathology ,medicine.medical_specialty ,Aflatoxin B1 ,Skin Neoplasms ,Time Factors ,Xeroderma pigmentosum ,Liver tumor ,Ratón ,Congenic ,Apoptosis ,Mice, Transgenic ,Biology ,medicine.disease_cause ,S Phase ,Mice ,medicine ,Animals ,Mice, Inbred C3H ,Homozygote ,Liver Neoplasms ,General Medicine ,medicine.disease ,Xeroderma Pigmentosum Group A Protein ,DNA-Binding Proteins ,Toxicity ,Carcinogens ,Hepatocytes ,Cancer research ,Female ,Skin cancer ,Carcinogenesis ,Nucleotide excision repair - Abstract
Xeroderma pigmentosum (XP) is an autosomal recessive hereditary disease featuring defective nucleotide excision repair (NER). XP patients are highly sensitive to sunlight and develop skin cancer at an early age. While the fact that XP patients have a large increase in mortality from skin cancers has been extensively documented, the relation between XP and internal tumors has received little attention. We therefore analyzed development of spontaneous and aflatoxin B(1) (AFB(1))-induced liver tumors in XPA-deficient congenic mice, originally created by repeated back-crosses with inbred C3H/HeN mice. Spontaneous liver tumors were assessed at the age of 16 months in two separate experiments using F5 and F10 lines. The incidence of and average number of spontaneous tumors per mouse were significantly higher in XPA-/- than in XPA+/+ and +/- mice. Similarly, F10 XPA-/- mice receiving i.p. injection of 0.6 or 1.5 mg/kg b.w. AFB(1) at 7 days of age demonstrated more liver tumors than their heterozygous or homozygous positive counterparts when examined at month 11. These results demonstrate that XPA-deficient mice have increased susceptibility to both spontaneous liver tumor development and AFB(1)-induced hepatocarcinogenesis.
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- 2002
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16. G649, an allelic variant of the human H2 receptor with low basal activity, is resistant to upregulation upon antagonist exposure
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Motonobu Anai, Takatoshi Ishikawa, Ryozo Nagai, Kouichi Inukai, Masao Omata, Toshihito Saitoh, Yasushi Fukushima, Katsunori Tsukuda, Makoto Funaki, Tomoichiro Asano, Takehide Ogihara, Yukiko Onishi, Midori Fujishiro, Hideyuki Sakoda, and Hiraku Ono
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medicine.medical_specialty ,Population ,Hamster ,CHO Cells ,Biology ,Downregulation and upregulation ,Histamine H2 receptor ,Cricetinae ,Internal medicine ,Cyclic AMP ,Genetics ,medicine ,Animals ,Humans ,Receptors, Histamine H2 ,education ,Receptor ,Alleles ,Pharmacology ,education.field_of_study ,Chinese hamster ovary cell ,Heterozygote advantage ,Up-Regulation ,Endocrinology ,Histamine H2 Antagonists ,Interleukin-21 receptor ,Mutation ,Molecular Medicine ,Cimetidine ,Histamine - Abstract
Orange et al reported an allelic variant of the human histamine H2 receptor, in which adenine 649 was replaced with guanine, to be more frequent in the schizophrenic population than controls in British Caucasians. The A649 to G change causes an Asn to Asp transition at amino acid position 217 in the third intracellular region, which is postulated to be important for receptor function. Herein, we analyzed the functional significance of this variant using wild-type and variant receptors expressed in Chinese hamster ovary cells. The variant receptor was associated with markedly lower basal cAMP productions than the wild-type receptor. Histamine-dependent cAMP productions via the variant receptor were lower as well. Treatment of cells expressing variant receptors with 10(-5) M ranitidine for 24 h resulted in a reduced degree of receptor upregulation as compared with the wild-type receptor. Thus, this is the first report of an allelic variant of the human H2 receptor which confers altered receptor function. To analyze gastric acid secretion in individuals with this variant, we examined 100 Japanese control subjects. However, neither heterozygotes nor homozygotes were found, suggesting that this variant, if present, is uncommon in the Japanese population.
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- 2001
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17. Protection against Malignant Progression of Spontaneously Developing Liver Tumors in Transgenic Mice Expressing O6-Methylguanine-DNA Methyltransferase
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Shoichi Matsukuma, Takatoshi Ishikawa, Xiusheng Qin, Seiichiro Shimizu, Shaomin Zhang, Yoko Nakatsuru, and Mirjana Zarkovic
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Male ,Genetically modified mouse ,Cancer Research ,Pathology ,medicine.medical_specialty ,Methyltransferase ,Liver tumor ,Mice, Transgenic ,Biology ,medicine.disease_cause ,Polymerase Chain Reaction ,DNA methyltransferase ,Mice ,O(6)-Methylguanine-DNA Methyltransferase ,Liver Neoplasms, Experimental ,medicine ,Transgenic mice ,Animals ,neoplasms ,Mice, Inbred C3H ,Oncogene ,Malignant Conversion ,Malignant conversion ,medicine.disease ,digestive system diseases ,Gene Expression Regulation, Neoplastic ,Cell Transformation, Neoplastic ,Genes, ras ,O6‐methylguanine‐DNA methyltransferase ,Oncology ,Tumor progression ,Mutation ,Cancer research ,Female ,Carcinogenesis ,Liver tumors ,Rapid Communication - Abstract
To study the effect of O(6)-methylguanine-DNA methyltransferase (MGMT) on carcinogenesis, we have previously generated MGMT transgenic mice overexpressing the bacterial MGMT gene, ada, and demonstrated that high MGMT levels in the liver suppress induction of liver tumors after treatment with an alkylating hepatocarcinogen. To examine the effects of life-long elevation of MGMT activity on mouse spontaneous liver tumor development, ada-transgenic and control non-transgenic mice were compared. We also examined mutations at codon 61 of the H-ras oncogene, reported as a hot spot in mouse liver tumors, using a direct DNA sequencing method. The results revealed no significant difference in tumor incidence or mutation spectrum, but interestingly, ada-transgenic mice were found to have fewer malignant tumors and survived longer, indicating a possible protective role of MGMT against malignant conversion.
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- 2000
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18. Genetic identification of bilateral primary or metastatic nonpapillary renal cell carcinoma
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Haruki Kume, Yoshihisa Takahashi, Shuji Kameyama, Tadaichi Kitamura, Hideaki Oda, T. Inoue, Takatoshi Ishikawa, T. Matsumoto, Yasuhito Shimizu, and Yoko Nakatsuru
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Male ,Pathology ,medicine.medical_specialty ,Ubiquitin-Protein Ligases ,Urology ,urologic and male genital diseases ,medicine.disease_cause ,Polymerase Chain Reaction ,Renal neoplasm ,Metastasis ,Ligases ,Neoplasms, Multiple Primary ,Renal cell carcinoma ,medicine ,Carcinoma ,Humans ,Carcinoma, Renal Cell ,neoplasms ,Aged ,Kidney ,business.industry ,Tumor Suppressor Proteins ,Cytogenetics ,Proteins ,DNA, Neoplasm ,Middle Aged ,medicine.disease ,Kidney Neoplasms ,female genital diseases and pregnancy complications ,medicine.anatomical_structure ,Von Hippel-Lindau Tumor Suppressor Protein ,Mutation ,Female ,Carcinogenesis ,business ,Kidney disease - Abstract
Objective To clarify the clonality of bilateral tumours by genetic analysis of bilateral renal cell carcinomas (RCCs) using the VHL gene, which is inactivated in ≈ 60% of RCCs and which plays a causal role in the development of most cases of nonpapillary RCC. Patients and methods The study included 20 patients; seven had von Hippel-Lindau disease, three had papillary RCC and 10 had nonpapillary RCC. Paraffin-embedded blocks of tumour tissue were obtained from two of the three patients with papillary RCC and from nine of 10 with nonpapillary disease; all three exons of VHL were examined by direct sequencing. Results As reported previously, no VHL mutations were found in papillary tumours. However, in five of the nine nonpapillary cases, VHL mutations were identified in tumours on one or both sides. Three of the tumours had the same mutation on both sides, confirming a common origin. In the remaining two patients, the mutation status differed between the sides, confirming a bilateral primary origin. The former cases were characterized by a relatively large tumour on one side and multiple tumours on the other. Conclusions In nonpapillary RCC multiplicity may suggest a metastatic origin. Such genetic information will be useful in treating and following patients with bilateral renal tumours.
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- 2000
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19. Targeted deletion of the H-ras gene decreases tumor formation in mouse skin carcinogenesis
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Taeko Ichise, Seiichiro Shimizu, Yoichi Gondo, Jun Miyoshi, Kazuki Nakao, Kazuhiro Ise, Atsu Aiba, Takatoshi Ishikawa, Motoya Katsuki, Kenji Nakamura, and Hosami Harada
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Male ,Cancer Research ,Skin Neoplasms ,Ratón ,Mutant ,DMBA ,Biology ,medicine.disease_cause ,Mice ,Genetics ,medicine ,Animals ,Molecular Biology ,Gene ,DNA Primers ,Mice, Knockout ,Mutation ,Base Sequence ,Oncogene ,Gene targeting ,DNA, Neoplasm ,Molecular biology ,Genes, ras ,Carcinogenesis ,Cell Division ,Gene Deletion - Abstract
To clarify the role of the H-Ras in vivo, we generated H-ras null mutant mice by gene targeting. In spite of the importance of the Ras in cell proliferation and differentiation, H-ras null mutant mice grew normally and were fertile. The oldest H-ras mutant mice grew to be more than 30 months old. We used the H-ras deficient mice to study the importance of the H-ras and other ras genes in the development of skin tumors induced by initiation with 7, 12-dimethylbenz(a)anthracene (DMBA) followed by promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA). We showed that H-ras null mutant mice develop approximately six times less papillomas compared with wild-type littermates after 20 weeks of TPA treatment. While all papillomas examined (17 out of 17) in wild-type mice have mutations of H-ras at codon 61, 13 (62%) out of 21 papillomas in H-ras null mutant mice have mutations of K-ras gene at codon 12, 13, or 61 and another eight (38%) papillomas have no mutations in these codons of K-ras or N-ras genes. This suggests that the activation of H-ras gene is critical in the wild-type mice, but the activation of K-ras gene can replace the H-ras activation in the initiation step of skin tumor development in the H-ras deficient mice. Oncogene (2000).
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- 2000
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20. ADAMTS-1: A metalloproteinase-disintegrin essential for normal growth, fertility, and organ morphology and function
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Kouji Matsushima, Yukiko Kurihara, Kouji Kuno, Takatoshi Ishikawa, Yoshio Yazaki, Hiroaki Nishimatsu, Hitoshi Yokoyama, Yoshio Oh-hashi, Hiroki Kurihara, Takayuki Shindo, Nobuo Moriyama, Takashi Wada, Masafumi Ogata, Hiroyuki Morita, Tomihiko Imai, Yuhui Wang, and Ryozo Nagai
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Male ,medicine.medical_specialty ,Disintegrins ,Growth ,Biology ,Matrix metalloproteinase ,Kidney ,Article ,Mice ,ADAMTS1 Protein ,Pregnancy ,Internal medicine ,Adrenal Glands ,medicine ,Disintegrin ,Morphogenesis ,Animals ,Humans ,Mice, Knockout ,Thrombospondin ,Metalloproteinase ,ADAMTS ,Ovary ,Uterus ,Metalloendopeptidases ,General Medicine ,ADAM Proteins ,Extracellular Matrix ,Protein Structure, Tertiary ,Mice, Inbred C57BL ,Fertility ,Phenotype ,medicine.anatomical_structure ,Endocrinology ,Commentary ,biology.protein ,Cancer research ,Female ,Infertility, Female ,ADAMTS Proteins - Abstract
金沢大学医薬保健研究域医学系, A disintegrin and metalloproteinase (ADAM) represents a protein family possessing both metalloproteinase and disintegrin domains. ADAMTS-1, an ADAM family member cloned from cachexigenic colon adenocarcinoma, is unusual in that it contains thrombospondin type I motifs and anchors to the extracellular matrix. To elucidate the biological role of ADAMTS-1, we developed ADAMTS-1-null mice by gene targeting. Targeted disruption of the mouse ADAMTS-1 gene resulted in growth retardation with adipose tissue malformation. Impaired female fertilization accompanied by histological changes in the uterus and ovaries also resulted. Furthermore, ADAMTS-1(-/-) mice demonstrated enlarged renal calices with fibrotic changes from the ureteropelvic junction through the ureter, and abnormal adrenal medullary architecture without capillary formation. ADAMTS-1 thus appears necessary for normal growth, fertility, and organ morphology and function. Moreover, the resemblance of the renal phenotype to human ureteropelvic junction obstruction may provide a clue to the pathogenesis of this common congenital disease.
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- 2000
21. Eel WT1 sequence and expression in spontaneous nephroblastomas in Japanese eel
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Yusuke Nakamura, Hideaki Oda, Yoko Nakatsuru, Akemi Yoshikawa, Ji-Jang Zhu, Kotaro Minami, Nobuaki Okamoto, Prince Masahito, and Takatoshi Ishikawa
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Male ,DNA, Complementary ,Genes, Wilms Tumor ,Molecular Sequence Data ,Gene Expression ,In situ hybridization ,Gene mutation ,Wilms Tumor ,Exon ,Complementary DNA ,Genetics ,medicine ,Animals ,Humans ,Point Mutation ,Tissue Distribution ,Amino Acid Sequence ,RNA, Messenger ,Japanese eel ,WT1 Proteins ,Gene ,In Situ Hybridization ,Zinc finger ,Polymorphism, Genetic ,Sequence Homology, Amino Acid ,biology ,Wilms' tumor ,Sequence Analysis, DNA ,General Medicine ,Anguilla ,Blotting, Northern ,biology.organism_classification ,medicine.disease ,Molecular biology ,Kidney Neoplasms ,DNA-Binding Proteins ,Gene Expression Regulation, Neoplastic ,Amino Acid Substitution ,Female ,Sequence Alignment ,Transcription Factors - Abstract
Nephroblastomas spontaneously developing in Japanese eel reared at farms for 5 to 9 months after collection from the wild [Masahito et al., Cancer Res., 52 (1992) 2575–2579] were investigated to cast light on the role of Wilms' tumor 1 gene (WT1) in eel kidney tumorigenesis. Cloning of the WT1 counterpart, EWT1, revealed that conservation of an alternative splice II site, located between the third and fourth zinc fingers, was conserved. The zinc finger domain was highly conserved. The transregulator region, sequences corresponding to exons 4 and 5 in WT1, were lacking in EWT1 cDNA. EWT1 was found to be expressed in kidney, testis and spleen and in situ hybridization revealed dark-stained immature cells in elver kidney to be positive. Although no EWT1 gene mutations were found in 38 eel nephroblastomas, 26 polymorphic nucleic acid changes were observed. Aberrant WT1 expression was noted in epithelial (12 out of 27; 44%) and nephroblastic cell histological types (three out of five; 60%) of eel nephroblastomas. On in situ hybridization the EWT1 expressive cells resembled human blastema cells, similar to those in human Wilms' tumor. These data demonstrated strong signals that the EWT1 protein may function in the development of eel kidney and play a role in genesis of nephroblastomas as in mammals.
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- 2000
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22. Acquired loss of p53 induces blastic transformation in p210bcr/abl-expressing hematopoietic cells: a transgenic study for blast crisis of human CML
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Hiroaki Honda, Takatoshi Ishikawa, Kuniko Wakazono, Yuji Tanaka, Hideaki Oda, Yoshio Yazaki, Hisamaru Hirai, Shinichi Aizawa, and Toshikazu Ushijima
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ABL ,Immunology ,breakpoint cluster region ,Chromosomal translocation ,Cell Biology ,Hematology ,Biology ,medicine.disease ,Philadelphia chromosome ,Biochemistry ,Haematopoiesis ,hemic and lymphatic diseases ,medicine ,Cancer research ,Kinase activity ,neoplasms ,K562 cells ,Chronic myelogenous leukemia - Abstract
Chronic myelogenous leukemia (CML) begins with an indolent chronic phase but inevitably progresses to a fatal blast crisis. Although the Philadelphia chromosome, which generates p210(bcr/abl), is a unique chromosomal abnormality in the chronic phase, additional chromosomal abnormalities are frequently detected in the blast crisis, suggesting that superimposed genetic events are responsible for disease progression. To investigate whether loss of p53 plays a role in the evolution of CML, we crossmated p210(bcr/abl)-transgenic (BCR/ABL(tg/-)) mice with p53-heterozygous (p53(+/-)) mice and generated p210(bcr/abl)-transgenic, p53-heterozygous (BCR/ABL(tg/-)p53(+/-)) mice, in which a somatic alteration in the residual normal p53 allele directly abrogates p53 function. The BCR/ABL(tg/-)p53(+/-) mice died in a short period compared with their wild-type (BCR/ABL(-/-)p53(+/+)), p53 heterozygous (BCR/ABL(-/-)p53(+/-)), and p210(bcr/abl) transgenic (BCR/ABL(tg/-)p53(+/+)) litter mates. They had rapid proliferation of blast cells, which was preceded by subclinical or clinical signs of a myeloproliferative disorder resembling human CML. The blast cells were clonal in origin and expressed p210(bcr/abl) with an increased kinase activity. Interestingly, the residual normal p53 allele was frequently and preferentially lost in the tumor tissues, implying that a certain mechanism facilitating the loss of p53 allele exists in p210(bcr/abl)-expressing hematopoietic cells. Our study presents in vivo evidence that acquired loss of p53 contributes to the blastic transformation of p210(bcr/abl)-expressing hematopoietic cells and provides insights into the molecular mechanism for blast crisis of human CML. (Blood. 2000;95:1144-1150)
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- 2000
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23. A defect in a single allele of the Mlh1 gene causes dissociation of the killing and tumorigenic actions of an alkylating carcinogen in methyltransferase-deficient mice
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Takatoshi Ishikawa, Teruhisa Tsuzuki, Fumio Ide, Kunihiko Sakumi, Mutsuo Sekiguchi, Riyoko Itoh, Hisaya Kawate, Yusaku Nakabeppu, Hajime Nawata, and Tetsuo Noda
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Alkylating Agents ,congenital, hereditary, and neonatal diseases and abnormalities ,Cancer Research ,Programmed cell death ,Methyltransferase ,Genotype ,Lymphoma ,Ratón ,DNA Mutational Analysis ,Biology ,MLH1 ,Lethal Dose 50 ,Mice ,O(6)-Methylguanine-DNA Methyltransferase ,Intestinal Neoplasms ,medicine ,Animals ,Genetic Predisposition to Disease ,Codon ,neoplasms ,Alleles ,Carcinogen ,Adaptor Proteins, Signal Transducing ,Mice, Knockout ,Nuclear Proteins ,nutritional and metabolic diseases ,Methylnitrosourea ,DNA, Neoplasm ,Neoplasms, Experimental ,Thymus Neoplasms ,General Medicine ,medicine.disease ,digestive system diseases ,Neoplasm Proteins ,Genes, ras ,Apoptosis ,Carcinogens ,Disease Progression ,Cancer research ,DNA mismatch repair ,Carrier Proteins ,MutL Protein Homolog 1 ,Gene Deletion - Abstract
Mice with mutations in both alleles of the Mgmt and the Mlh1 gene, the former encoding a DNA repair methyltransferase and the latter a protein functioning at an early step of mismatch repair, are as resistant to the killing action of alkylating agents as are wild-type mice. These mice yielded a large number of tumors when exposed to alkylating carcinogens, but this characteristic was subdued since they also showed a relatively high level of spontaneous tumorigenicity, as a consequence of the defect in mismatch repair. This complexity is now resolved by introducing the Mlh1(+/-) mutation, instead of Mlh1(-/-), in these methyltransferase-deficient mice. Mgmt(-/-) Mlh1(+/-) mice, with about half the amount of MLH1 protein as Mgmt(-/-) Mlh1(+/+) mice, were resistant to the killing action of N-methyl-N-nitrosourea (MNU), up to the level of 30 mg/kg body wt. Eight weeks after exposure to this dose of MNU, 40% of MNU-treated Mgmt(-/-) Mlh1(+/-) mice had thymic lymphomas and there were no tumors in those mice not given the treatment. It seems that the cellular content of MLH1 protein is a critical factor for determining if damaged cells enter into either one of the two pathways leading to mutation induction or to apototic cell death. Loss of Mlh1 expression was frequently observed in tumors of Mgmt(-/-) Mlh1(+/-) mice and this might be related to progression of the tumors.
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- 2000
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24. Benzo[ a ]pyrene carcinogenicity is lost in mice lacking the aryl hydrocarbon receptor
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Takatoshi Ishikawa, Haruki Kume, Yasuhito Shimizu, Yoko Nakatsuru, Masao Ichinose, Junsei Mimura, Yoshihisa Takahashi, and Yoshiaki Fujii-Kuriyama
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Male ,Skin Neoplasms ,Genotype ,Fibrosarcoma ,Gene Expression ,Aryl hydrocarbon receptor repressor ,Mice ,chemistry.chemical_compound ,Subcutaneous injection ,Rhabdomyosarcoma ,Gene expression ,Benzo(a)pyrene ,Animals ,RNA, Messenger ,Carcinogen ,Skin ,Mice, Knockout ,Multidisciplinary ,Papilloma ,biology ,CYP1A2 ,Cytochrome P450 ,Biological Sciences ,respiratory system ,Aryl hydrocarbon receptor ,Molecular biology ,respiratory tract diseases ,Mice, Inbred C57BL ,Keratoacanthoma ,Receptors, Aryl Hydrocarbon ,chemistry ,Immunology ,Carcinogens ,Carcinoma, Squamous Cell ,biology.protein ,Female - Abstract
The contribution of the aryl hydrocarbon receptor (AhR) in induction of a battery of xenobiotic-metabolizing enzymes has been studied extensively. However, no direct proof has been obtained that it plays a role in modulating carcinogenesis. To address the question of whether AhR is required for tumor induction, we have investigated the response of AhR-deficient mice to benzo[ a ]pyrene (B[ a ]P), a widely distributed environmental carcinogen. B[ a ]P treatment induced expression of the cytochrome P450 gene Cyp1a1 in the skin and liver of AhR-positive mice bearing +/+ and +/− genotypes and did not induce expression of the cytochrome P450 gene Cyp1a1 in AhR-null mice in either skin or liver. In contrast, Cyp1a2 gene expression was positive in liver irrespective of the presence or absence of the AhR gene, or B[ a ]P treatment, although its inducibility was lost in the AhR(−/−) mouse. All AhR-positive male mice of both +/+ and +/− genotypes that received subcutaneous injection of B[ a ]P (2 mg) on the first and the eighth days had developed subcutaneous tumors at the site of injection at the end of the 18-week experiment. In contrast, no tumors were apparent in any of the AhR-deficient mice. Likewise, topical application of B[ a ]P (200 μg) at weekly intervals to the skin of female mice for 25 weeks produced skin tumors only in the AhR-positive mice. Thus the carcinogenic action of B[ a ]P may be determined primarily by AhR, a transcriptional regulator of the gene for CYP1A1. The results of the present study provide direct evidence that AhR is involved in carcinogenesis.
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- 2000
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25. Expression of E2A-HLF Chimeric Protein Induced T-Cell Apoptosis, B-Cell Maturation Arrest, and Development of Acute Lymphoblastic Leukemia
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Hiroaki Honda, Yoshio Yazaki, Toshiya Inaba, Yasuhiro Ebihara, Takahiro Suzuki, Kohichiro Tsuiji, Hideaki Oda, Takatoshi Ishikawa, Hisamaru Hirai, and Tatsutoshi Nakahata
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Transcriptional Activation ,Programmed cell death ,Recombinant Fusion Proteins ,T-Lymphocytes ,Transgene ,Cellular differentiation ,Immunology ,Apoptosis ,Mice, Transgenic ,Spleen ,Thymus Gland ,Biology ,Kidney ,Biochemistry ,Translocation, Genetic ,Mice ,Acute lymphocytic leukemia ,medicine ,Animals ,Humans ,Promoter Regions, Genetic ,B-Lymphocytes ,Leucine Zippers ,Acute leukemia ,T lymphocyte ,Cell Biology ,Hematology ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,medicine.disease ,Fusion protein ,Molecular biology ,Adenovirus E2 Proteins ,DNA-Binding Proteins ,Basic-Leucine Zipper Transcription Factors ,Enhancer Elements, Genetic ,medicine.anatomical_structure ,Liver ,Dimerization ,Transcription Factors - Abstract
The E2A-HLF fusion gene, generated by t(17;19)(q22;p13) in acute lymphoblastic leukemia (ALL), encodes a chimeric transcription factor in which the trans-activating domains of E2A are fused to the DNA-binding and dimerization domains of hepatic leukemic factor (HLF). To investigate its biological role, we generated transgenic mice expressing E2A-HLF using Ig enhancer and promoter, which direct transgene expression in cells committed to the lymphoid lineage. The transgenic mice exhibited abnormal development in the thymus and spleen and were susceptible to infection. The thymus contained small numbers of thymocytes, and TUNEL staining showed that higher population of thymocytes were undergoing apoptosis. The spleen exhibited a marked reduction in splenic lymphocytes and the flow cytometric analyses and the in vitro colony formation assays showed that the B-cell maturation was blocked at a very early developmental stage. These findings indicated that the expression ofE2A-HLF induced T-cell apoptosis and B-cell maturation arrest in vivo and that the susceptibility of the transgenic mice to infection was due to immunodeficiency. Moreover, several transgenic mice developed acute leukemia, classified as T-ALL based on the surface marker analysis and DNA rearrangements, suggesting that an additional event is required for malignant transformation of lymphoid cells expressing E2A-HLF. Our findings provide insight into the biological function of E2A-HLF in lymphoid development and also its role in leukemogenesis.
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- 1999
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26. Immunohistochemical and Molecular Analysis of Giant Cell Carcinoma of the Pancreas
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Mitsuyasu Toyoda, Keiichiro Yamamoto, Yusei Ikeda, Takatoshi Ishikawa, Tohru Inoue, Shinji Morishita, Tatsuhito Ashizawa, and Yasuo Imai
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Male ,Giant Cell Carcinoma ,Pathology ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Antigens, Differentiation, Myelomonocytic ,Osteoclasts ,Gene mutation ,Biology ,Epithelium ,Mesoderm ,Loss of heterozygosity ,Endocrinology ,Antigens, CD ,Internal Medicine ,medicine ,Humans ,Vimentin ,Aged ,Hepatology ,CD68 ,Mesenchymal stem cell ,Carcinoma, Giant Cell ,Middle Aged ,Immunohistochemistry ,Pancreatic Neoplasms ,Genes, ras ,medicine.anatomical_structure ,Giant cell ,Mutation ,Keratins ,Female ,Pancreas - Abstract
We performed molecular biological studies as well as immunohistochemical analysis of three cases of giant cell carcinoma of the pancreas. Histologically. one case was a pleomorphic giant cell carcinoma consisting of pleomorphic giant/ small cells and spindle cells, one an osteoclast-like giant cell tumor composed of osteoclastoid giant cells and pleomorphic small cells, and one a pleomorphic giant cell carcinoma with osteoclastoid giant cells. Immunohistochemically, pleomorphic giant cells and small pleomorphic cells were positive for epithelial and mesenchymal markers throughout the cases. Osteoclastoid cells were strongly positive for PG-M1 (CD68), but negative for lysozyme and epithelial markers. Pleomorphic spindle cells showed the same immunoreactivity as pleomorphic giant/small cells. Genetically, all cases contained a mutation in the K-ras (codons 12, 13) oncogene, but neither p53 (exons 5-8) nor p16 INK4 (exons 1. 2) gene mutations were found in any case. Furthermore, Loss of heterozygosity (LOH) of the p53, p16 INK4, APC, and DPC4 gene loci was not found in any of the cases. Immunohistochemical study demonstrated this tumor to be of epithelial origin with mesenchymal differentiation. Genetically, initiation of the tumor is similar to that of usual ductal adenocarcinoma, but progression might be rather different. The peculiar histologic and biologic features of this tumor would be the result of changes in other functional genes.
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- 1999
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27. Mutations of the humanMUT S homologue 6 gene in ampullary carcinoma and gastric cancer
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Yasuo Imai, Tohru Inoue, and Takatoshi Ishikawa
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Genetics ,Cancer Research ,Mutation ,Biology ,Gene mutation ,medicine.disease_cause ,Frameshift mutation ,MSH6 ,Oncology ,Cancer research ,medicine ,Missense mutation ,Microsatellite Mutator Phenotype ,Carcinogenesis ,Gene - Abstract
MSH6 has been implicated in repair of single base mispairs and single-base deletionlinsertion mutations. Established MSH6-null mice present a frequent occurrence of gastrointestinal tumors without microsatellite instability (MI), suggesting the possibility of the APC gene being a mutational target. Because human ampullary carcinomas and gastric cancers manifest frequent missense or I-base deletion mutations in cancer-related genes such as p53 and TGFβ-RII, we suspected that the hMSH6 gene mutation might play a role in the carcinogenesis process. Out of the whole coding sequences, hMSH6 (C) 8 (codons 1085-1087) and hMSH3 (A) 8 repeats (codons 381-383) have been shown to be hotspots for frameshift mutations in a certain group of cancers, contributing to an increased genomic instability. We therefore investigated mutations of hMSH6 (C) 8 and hMSH3 (A) 8 in association with microsatellite mutator phenotype (MMP) in 18 ampullary carcinomas and 30 gastric cancers. In addition, overexpression of the P53 protein and mutational status of APC (AG) 5 (codons 1462-1465) and (A) 6 (codons 1554-1556) repeats were also investigated as a potential target of genetic instability secondary to MSH6 dysfunction. Mutation of the hMSH6 gene was not found in ampullary carcinomas and was irrelevant to TGFβ-RII gene mutation. Mutation of the hMSH6 gene was observed in a subset of gastric cancers (4/30, 13.3%), but was not associated with P53 overexpression or APC gene mutation. In contrast to MSH6-null mice that do not show Ml, hMSH6 gene mutation in human gastric cancers was closely correlated with MMP (3/10 MMP vs. 1/20 non-MMP). In conclusion, hMSH6 mutation appears only in association with MMP and may underlie augmented MI, resulting in missense or I-base frameshift mutations in other genes in human gastric cancers.
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- 1998
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28. Cardiovascular anomaly, impaired actin bundling and resistance to Src-induced transformation in mice lacking p130Cas
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Toshiki Saito, Yoshio Yazaki, Kenji Nakamura, Takahiro Suzuki, Hideaki Oda, Tetsuya Nakamoto, Hisamaru Hirai, Motoya Katsuki, Zen-ichiro Honda, Takatoshi Ishikawa, Hiroaki Honda, Ryuichi Sakai, and Kazuki Nakao
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Sarcomeres ,Stress fiber ,Podosome ,Recombinant Fusion Proteins ,Molecular Sequence Data ,Biology ,Oncogene Protein pp60(v-src) ,Mice ,Genetics ,Animals ,Amino Acid Sequence ,Phosphorylation ,Cells, Cultured ,Actin ,Cell Line, Transformed ,Mice, Knockout ,Retinoblastoma-Like Protein p130 ,Myocardium ,Proteins ,Heart ,Cell migration ,Fibroblasts ,Phosphoproteins ,Actin cytoskeleton ,Actins ,Cell biology ,Actin Cytoskeleton ,Cell Transformation, Neoplastic ,Crk-Associated Substrate Protein ,Liver ,BCAR1 ,embryonic structures ,Blood Vessels ,Proto-oncogene tyrosine-protein kinase Src - Abstract
p130Cas (Cas), the protein encoded by the Crkas gene (also known as Cas), is an adaptor molecule with a unique structure that contains a Src homology (SH)-3 domain followed by multiple YXXP motifs and a proline-rich region. Cas was originally cloned as a highly tyrosine-phosphorylated protein in cells transformed by v-Src (refs 2,3) or v-Crk (ref. 4) and has subsequently been implicated in a variety of biological processes including cell adhesion, cell migration, growth factor stimulation, cytokine receptor engagement and bacterial infection. To determine its role in vivo, we generated mice lacking Cas. Cas-deficient embryos died in utero showing marked systemic congestion and growth retardation. Histologically, the heart was poorly developed and blood vessels were prominently dilated. Electron microscopic analysis of the heart revealed disorganization of myofibrils and disruption of Z-disks. In addition, actin stress fiber formation was severely impaired in Cas-deficient primary fibroblasts. Moreover, expression of activated Src in Cas-deficient primary fibroblasts did not induce a fully transformed phenotype, possibly owing to insufficient accumulation of actin cytoskeleton in podosomes. These findings have defined Cas function in cardiovascular development, actin filament assembly and Src-induced transformation.
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- 1998
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29. Development of Acute Lymphoblastic Leukemia and Myeloproliferative Disorder in Transgenic Mice Expressing p210bcr/abl: A Novel Transgenic Model for Human Ph1-Positive Leukemias
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Hideaki Oda, Hisamaru Hirai, Yoshio Yazaki, Tsuyoshi Takahashi, Hiroaki Honda, Takatoshi Ishikawa, Owen N. Witte, Keiya Ozawa, and Takahiro Suzuki
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Male ,Receptors, Steroid ,Recombinant Fusion Proteins ,Immunology ,Fusion Proteins, bcr-abl ,Mice, Transgenic ,Nerve Tissue Proteins ,Biology ,Philadelphia chromosome ,Biochemistry ,Transgenic Model ,Mice ,Leukemic Infiltration ,Leukemia, Myelogenous, Chronic, BCR-ABL Positive ,hemic and lymphatic diseases ,Acute lymphocytic leukemia ,medicine ,Animals ,Humans ,Transgenes ,Kinase activity ,Promoter Regions, Genetic ,Lung ,Hyperplasia ,Myeloproliferative Disorders ,Receptors, Thyroid Hormone ,ABL ,Gene Expression Regulation, Leukemic ,breakpoint cluster region ,Nuclear Proteins ,Cell Biology ,Hematology ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,medicine.disease ,DNA-Binding Proteins ,Disease Models, Animal ,Cell Transformation, Neoplastic ,Cancer research ,Female ,Blast Crisis ,Granulocytes ,Chronic myelogenous leukemia ,K562 cells - Abstract
The Philadelphia (Ph1) chromosome can be detected in chronic myelogenous leukemia (CML) and a significant number of acute lymphoblastic leukemia (ALL) cases. Generation of p210bcr/abl, a chimeric protein with enhanced kinase activity, is thought to be involved in the pathogenesis of these diseases. To elucidate the biological properties of p210bcr/abl and to create an animal model for human Ph1-positive leukemias, we generated transgenic mice expressing p210bcr/abl driven by the promoter of the tec gene, a cytoplasmic tyrosine-kinase preferentially expressed in the hematopoietic lineage. The founder mice showed excessive proliferation of lymphoblasts shortly after birth and were diagnosed as suffering from ALL based on surface marker and Southern blot analyses. Expression and enhanced kinase activity of the p210bcr/abl transgene product were detected in the leukemic tissues. In contrast, transgenic progeny exhibited marked granulocyte hyperplasia with thrombocytosis after a long latent period and developed myeloproliferative disorders (MPDs) closely resembling human CML. Expression of p210bcr/abl mRNA in the proliferating granulocytes was detected by RT-PCR. In particular, one MPD mouse showed remarkable proliferation of blast cells in the lung, which might represent an extramedullar blast crisis. The results demonstrate that the expression of p210bcr/abl in hematopoietic progenitor cells in transgenic mice can contribute to two clinically distinct hematopoietic malignancies, CML and ALL, indicating that this transgenic system provides a novel transgenic model for human Ph1-positive leukemias.
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- 1998
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30. Loss of imprinting of igf2 in renal-cell carcinomas
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Hideaki Oda, Takatoshi Ishikawa, Tohru Inoue, Haruki Kume, and Yasuhito Shimizu
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Adult ,Male ,Cancer Research ,medicine.medical_specialty ,RNA, Untranslated ,animal structures ,endocrine system diseases ,Cell ,Muscle Proteins ,Biology ,urologic and male genital diseases ,medicine.disease_cause ,Genetic determinism ,Loss of heterozygosity ,Genomic Imprinting ,Insulin-Like Growth Factor II ,Internal medicine ,Gene expression ,medicine ,Carcinoma ,Humans ,RNA, Messenger ,Imprinting (psychology) ,Carcinoma, Renal Cell ,Alleles ,Aged ,Middle Aged ,medicine.disease ,Kidney Neoplasms ,female genital diseases and pregnancy complications ,Endocrinology ,medicine.anatomical_structure ,Oncology ,embryonic structures ,Cancer research ,Female ,RNA, Long Noncoding ,Genomic imprinting ,Carcinogenesis - Abstract
Loss of imprinting (LOI) of the igf2 and h19 genes has been found not only in embryonal tumors but also in common adult cancers. To determine any possible role of genomic imprinting in the development of renal-cell carcinomas (RCCs), we examined the imprinting status of igf2 and h19 in a series of 22 such tumors, and studied its relation to their mRNA expression. Of 14 RCC specimens heterozygous for the Apal polypmorphism, 7 (50%) showed LOI of igf2. In contrast, for h19 all 9 informative cases maintained imprinting. Furthermore, all 7 cases with LOI transcribed igf2 mRNA at elevated levels, while H 19 expression was low regardless of the imprinting status compared with that of background level in each case. These results suggest that LOI of igf2, but not of h19, plays a role in the case of human RCC. However, in contrast to that in Wilms' tumor, LOI in RCC was not associated with any specific down-regulation of h19.
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- 1998
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31. Frequent Somatic Mutations of theAPCandp53Genes in Sporadic Ampullary Carcinomas
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Takatoshi Ishikawa, Yasuo Imai, Naomi Tsurutani, Hideaki Oda, Tohru Inoue, and Yoko Nakatsuru
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p53 ,Male ,Ampulla of Vater ,Cancer Research ,Genes, APC ,Adenomatous polyposis coli ,Common Bile Duct Neoplasms ,Nonsense mutation ,Gene mutation ,medicine.disease_cause ,Polymerase Chain Reaction ,Article ,Familial adenomatous polyposis ,Loss of heterozygosity ,Duodenal Neoplasms ,medicine ,Humans ,Point Mutation ,Missense mutation ,Neoplasm Invasiveness ,Aged ,Neoplasm Staging ,Sequence Deletion ,Aged, 80 and over ,Genetics ,Ampullary carcinoma ,biology ,Point mutation ,Liver Neoplasms ,Exons ,Middle Aged ,Genes, p53 ,medicine.disease ,APC ,Pancreatic Neoplasms ,Adenomatous Polyposis Coli ,Oncology ,Lymphatic Metastasis ,Mutation ,biology.protein ,Cancer research ,Female ,Carcinogenesis - Abstract
Although a close relation of somatic mutations of the adenomatous polyposis coli gene with ampullary carcinomas in familial adenomatous polyposis patients has been reported, the possible association with sporadic ampullary neoplasms has not been fully examined. We have therefore investigated loss of heterozygosity at the adenomatous polyposis coli locus and the mutational status of a portion of the adenomatous polyposis coli gene, including the mutation cluster region, in 17 ampullary carcinomas of non-familial adenomatous polyposis patients. Alteration of the adenomatous polyposis coli gene was found in 8 of 17 (47.1%) cases, as missense or insertion mutations, with or without loss of heterozygosity. Additional investigation of p53 (exons 5-8) and K-ras (codons 12 and 13) gene mutations revealed a striking mutational pattern of the p53 gene. Nine of the 17 cases demonstrated a total of 12 mutations, 6 clustered at codon 189 and 3 at codon 166. Furthermore, 5 of the 12 mutations were nonsense mutations. Regarding the K-ras gene, 4 of the 17 (23.5%) cases had mutations in codon 12, 3 of the 4 cases being derived from the intraduodenal bile duct. The findings indicate that alterations of the adenomatous polyposis coli and the p53 genes are relatively frequent in sporadic ampullary carcinomas. In particular, the clustering at specific p53 codons might offer an etiological clue to clarify ampullary carcinogenesis. Mutations of the K-ras gene, on the other hand, might be characteristic of intraduodenal bile duct origin.
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- 1997
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32. Prevalence ofp53 mutations and protein expression in esophageal cancers in southern Thailand
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Supaporn Suwiwat, Yasuhito Shimizu, Hideaki Oda, and Takatoshi Ishikawa
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Cancer Research ,Pathology ,medicine.medical_specialty ,education.field_of_study ,Tumor suppressor gene ,Esophageal disease ,Population ,Cancer ,Biology ,medicine.disease_cause ,medicine.disease ,Oncology ,Epidermoid carcinoma ,CpG site ,medicine ,Carcinogenesis ,education ,Grading (tumors) - Abstract
To investigate p53 alterations in esophageal squamous-cell carcinomas of patients in the high-risk area of southern Thailand, 72 paraffin-embedded samples were analyzed immunohistochemically for p53 protein expression and 16 frozen samples for p53 mutational status. Forty-two of the 72 tumors (58.3%) showed p53 protein accumulation in the nuclei of tumor cells. Expression of p53 in tumors was not significantly correlated with gender, histological grading, depth of invasion, node involvement, smoking or alcohol consumption. Analysis of the p53 gene in a sub-set of 16 tumors showed mis-sense mutations in 7 out of 11 p53-positive and 1 out of 5 p53-negative tumors. The p53 mutational spectrum was 50% transitions (3 C-to-T and 1 G-to-A, all occurring at CpG dinucleotide sites) and 50% transversions (one each, C-to-G, G-to-T, T-to-G, and T-to-A). Our findings support the hypothesis that alterations of p53 are involved in the carcinogenesis of most squamous-cell carcinomas of the esophagus, irrespective of the population and the factors responsible for carcinogenesis. The mutation profile of the p53 gene might indicate etiologic contributions of different mutagen exposures in patients from high-risk areas of southern Thailand. Int. J. Cancer 72:23–26, 1997. © 1997 Wiley-Liss Inc.
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- 1997
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33. Design, synthesis, and evaluation of orally active fibrinogen inhibitors
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Takatoshi Ishikawa, Akito Tanaka, Hisashi Takasugi, Yukio Motoyama, Hiroyoshi Sakai, and Toshiaki Aoki
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chemistry.chemical_classification ,Dipeptide ,Organic Chemistry ,Clinical Biochemistry ,Pharmaceutical Science ,Peptide ,Pharmacology ,Fibrinogen ,Biochemistry ,Chemical synthesis ,In vitro ,Sulfone ,chemistry.chemical_compound ,chemistry ,In vivo ,Oral administration ,Drug Discovery ,medicine ,Molecular Medicine ,Molecular Biology ,medicine.drug - Abstract
Low molecular weight and orally active fibrinogen inhibitors are described. The compounds studied in this work were rationally designed based on a metabolic study of a peptidic fibrinogen inhibitor, 4-(4-amidinophenoxy)butanoylaspartylvaline (1, FK633), which led to the synthesis of a potent and orally active antiplatelet agent, 4-(4-amidinophenoxy)butanoylaspartylvalylthiomorpholine 1,1-dioxide (3f, FR158999).
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- 1997
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34. Mutational Analysis of thep53and K-rasGenes and Allelotype Study of theRb-1Gene for Investigating the Pathogenesis of Combined Hepatocellular-Cholangiocellular Carcinomas
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Tohru Inoue, Yoko Nakatsuru, Masami Arai, Yasuo Imai, Hideaki Oda, Seiichiro Shimizu, and Takatoshi Ishikawa
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p53 ,Male ,Cancer Research ,Carcinoma, Hepatocellular ,Tumor suppressor gene ,Rb‐1 ,DNA Mutational Analysis ,Biology ,medicine.disease_cause ,Article ,Cholangiocarcinoma ,Neoplasms, Multiple Primary ,Carcinoembryonic antigen ,Combined hepatocellular‐cholangiocellular carcinoma ,K‐ras ,Keratin ,Carcinoma ,medicine ,Humans ,Genes, Retinoblastoma ,Allelotype ,Alleles ,Aged ,chemistry.chemical_classification ,Mutation ,Liver Neoplasms ,Middle Aged ,Genes, p53 ,medicine.disease ,Carcinoembryonic Antigen ,Neoplasm Proteins ,Genes, ras ,Oncology ,chemistry ,Hepatocellular carcinoma ,Cancer research ,biology.protein ,Keratins ,Female ,Carcinogenesis ,Gene Deletion - Abstract
Because combined hepatocellular‐cholangiocellular carcinoma is rare and its biological features and pathogenesis have not been well established, we investigated alterations of the p53, K‐ras and Rb‐1 genes, as well as expression patterns of carcinoembryonic antigen and keratin, in seven combined hepatocellular‐cholangiocarcinoinas out of 557 hepatocellular carcinomas autopsied at Tokyo University during 30 years. Mutations of the p53 gene were found in two cases, at codon 244 (GGC to TGC) in the cholangiocellular carcinoma component of case 1 (mixed type, showing an intimate intermingling of both elements) and at codon 234 (TAC to AAC) in both components of case 5 (combined type, consisting of contiguous but independent masses of both elements). Mutation of the K‐ras gene (codon 12, GGT to GAT) was seen only in the cholangiocellular carcinoma component of clinically apparent double cancer, case 6. Allelic alteration of the Rb‐1 gene was observed in two cases, deletion of both alleles in the hepatocellular carcinoma component of case 3 (combined type) and replication error of the same pattern in both components of case 4 (mixed type). Immunohistochemical analysis showed that the hepatocellular carcinoma components of five cases (cases 2, 3, 5, 6, 7) were immunoreactive for keratin, suggesting biliary epithelial transformation. In four of the five cases (cases 3 and 5 combined, case 7 mixed and case 6 double cancer), cholangiocellular carcinoma components were also positive for keratin. These results suggest that both components of combined hepatocellular‐cholangio‐carcinoma have the same genetic and phenotypic character and might have arisen from the same origin in some cases.
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- 1996
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35. Design, synthesis, and evaluation of fibrinogen inhibitors, ω-(p-amidinophenoxy) alkanoylaspartic acid derivatives
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Akito Tanaka, Yukio Motoyama, Isao Nakanishi, Hiroyoshi Sakai, Toshiaki Aoki, Takatoshi Ishikawa, Hisashi Takasugi, and Mitsuru Ohkubo
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Platelet aggregation ,Chemistry ,Stereochemistry ,Organic Chemistry ,Clinical Biochemistry ,Pharmaceutical Science ,Tripeptide ,Adhesion ,Fibrinogen ,Biochemistry ,Design synthesis ,Drug Discovery ,medicine ,Molecular Medicine ,Molecular Biology ,medicine.drug - Abstract
Low molecular weight inhibitors of platelet aggregation are described. Compounds studied in this work were derived from the presumed active conformation of the adhesion tripeptide, ArgGlyAsp, using computer simulations. These studies led to the synthesis of a potent anti-platelet agent, 4-(4-amidinophenoxy)-butanoylaspartylvaline (6, FK633).
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- 1996
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36. Germ Cell Neoplasms in Japanese Medaka
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John W. Fournie, William W. Walker, William E. Hawkins, and Takatoshi Ishikawa
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Pathology ,medicine.medical_specialty ,Kidney ,Germ cell neoplasm ,Oryzias ,Japanese Medaka ,Aquatic Science ,Biology ,biology.organism_classification ,medicine.disease_cause ,Peritoneal cavity ,medicine.anatomical_structure ,medicine ,Mitotic Figure ,Carcinogenesis ,Spermatogenesis - Abstract
Twenty-six cases of germ cell neoplasms were identified from approximately 10,000 specimens of Japanese medaka Oryzias latipes used in carcinogenesis bioassays and examined histologically. The neoplasms resembled spermatocytic seminomas and occurred in both female and male specimens. Most were confined to the peritoneal cavity but some infiltrated adjacent organs, including the kidney. The presence of neoplastic cells in the heart, gill capillaries, and orbital cavity suggested that some neoplasms had spread by way of the cardiovascular system. Histologically, the components of neoplasms resembled the cellular stages of spermatogenesis. Primary spermatocytes, secondary spermatocytes, and spermatids, but not mature spermatozoa, could be recognized. The cellular patterns of the neoplasms were solid, lobular, or a combination of those. Mitotic figures were not frequently seen in the lesions. Many of the neoplasms in males contained scattered cells that resembled oocytes. The occurrence of the neopla...
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- 1996
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37. Sequence Analysis, Chromosomal Location, and Developmental Expression of the Mouse Preproendothelin-1 Gene
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Koji Maemura, Yukiko Kurihara, Yoshio Yazaki, Hideaki Oda, Debra J. Gilbert, Takatoshi Ishikawa, Nancy A. Jenkins, Neal G. Copeland, and H. Kurihara
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Male ,medicine.hormone ,DNA, Complementary ,Sequence analysis ,Molecular Sequence Data ,Gene Expression ,Biology ,Endothelins ,Mice ,Exon ,Gene mapping ,Gene expression ,Genetics ,medicine ,Animals ,Humans ,Amino Acid Sequence ,Protein Precursors ,Peptide sequence ,Gene ,Mice, Inbred BALB C ,Base Sequence ,Endothelin-1 ,Sequence Homology, Amino Acid ,Chromosome Mapping ,Molecular biology ,Open reading frame ,Female ,Sequence Analysis - Abstract
Recent studies have designated endothelins (ETs) as morphogenetic factors in embryonic development. In the present study, we cloned and characterized the mouse preproendothelin-1 (preproET-1) gene (Edn1) and examined its expression in reference to development. Edn1 comprises five exons, and the open reading frame encodes the 202-amino-acid preproET-1. The sequences and structural organization of Edn1 are highly homologous to those of other species, especially in the terminal 200-bp sequence of the 3'-noncoding region. Interspecific backcross mapping located Edn1 in the central region of chromosomal 13, where a mouse mutation, congenital hydrocephalus (ch), is also mapped. The highest expression of Edn1 mRNA is detected in the lung in adult mice, whereas Edn1 is predominantly expressed in the epithelium and mesenchyme of the pharyngeal arches and in the endothelium of the large arteries. Edn1 expression and ET-1 peptide levels in the lung progressively increased during the perinatal stage, whereas the expression of Edn3, a gene encoding ET-3, reciprocally decreases. These results suggest that Edn1 expression is developmentally regulated in different tissues and organs in mice in a spatial- and temporal-specific manner.
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- 1996
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38. ACCELERATED PAPER: Targeted disruption of the DNA repair methyltransferase gene renders mice hypersensitive to alkylating agent
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Tomoo Iwakuma, Seiichiro Shimizu, Kazuki Nakao, Sakumi Kunihiko, Motoya Katsuki, Teruhisa Tsuzuki, Mutsuo Sekiguchi, Yohei Tominaga, Akiko Shiraishi, Hisato Igarashi, Takatoshi Ishikawa, Kenji Nakamura, Hisaya Kawate, and Shaomin Zhang
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Cancer Research ,Mutation ,Methyltransferase ,Gene targeting ,General Medicine ,Biology ,medicine.disease_cause ,Molecular biology ,chemistry.chemical_compound ,medicine.anatomical_structure ,Biochemistry ,chemistry ,Methyltransferase Gene ,medicine ,Bone marrow ,Stem cell ,Gene ,DNA - Abstract
Alkylation of DNA at the O(6)-position of guanine is one of the most critical events leading to induction of mutation as well as to cancer. The enzyme O(6)-methylguanine-DNA methyltransferase repairs this and related lesions in DNA. By means of gene targeting, we established mouse lines deficient in the methyltransferase gene and tissues from these mice contained no methyltransferase activity. Administration of methylnitrosourea to these gene-targeted mice led to early death, and normal mice treated in the same manner showed no untoward effects. In mice given methylnitrosourea treatment, the bone marrow became hypocellular and there was a drastic decrease in the number of leukocytes and platelets, thereby indicating an impaired reproductive capacity of hematopoietic stem cells. Methyltransferase apparently protected these mice from the pancytopenia caused by the alkylating agent.
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- 1996
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39. Detection of Ultraviolet Photoproducts in Mouse Skin Exposed to Natural Sunlight
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Shaomin Zhang, Seiichiro Shimizu, Xiusheng Qin, Hideaki Oda, Takatoshi Ishikawa, Yukari Yamazaki, Osamu Nikaido, Mirjana Zarkovic, and Yoko Nakatsuru
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Cancer Research ,Ultraviolet Rays ,Pyrimidine dimer ,Human skin ,medicine.disease_cause ,Article ,Mice ,In vivo ,medicine ,Animals ,UV‐photoproduct ,Carcinogen ,Skin ,Sunlight ,Mice, Inbred C3H ,integumentary system ,Chemistry ,Mouse skin ,Molecular biology ,Immunohistochemistry ,Oncology ,Pyrimidine Dimers ,Female ,sense organs ,Quantitative analysis (chemistry) ,Ultraviolet - Abstract
In the present study, we for the first time investigated the formation of ultraviolet (UV) photoproducts, cyclobutane pyrimidine dimers (CPDs), pyrimidine‐pyrimidone (6–4) photoproducts (64PPs) and Dewar isomers, in vivo in shaved and depilated C3H/HeN mouse skin exposed to natural sunlight (NSL) at noon for 5 min to 1 h in mid‐summer, using a highly sensitive immunohistochemical method. This method permits the quantitative analysis of UV‐photoproducts in formalin‐fixed, paraffin‐embedded sections with specific antibodies against CPDs, 64PPs and Dewar isomers. We demonstrated that the induction of CPDs in vivo in mouse skin by NSL was exposure time‐dependent, but the accumulation of 64PPs or Dewar isomers was comparatively low in the skin sections from mice exposed to NSL in vivo. The results indicate that CPDs are the main photoproducts in vivo induced by sunlight and that their formation and repair may be important in connection with carcinogenesis in sun‐exposed areas of human skin.
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- 1996
40. Management of calcium and bone abnormalities in hemodialysis patients
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T. Takaaki Nishijima, Tsutomu Shigeoka, Koji Tani, Noboru Kubodera, Nobuaki Kawai, T. Misa Horio, Tayuki Inoue, T. Hiroyuki Araki, Takatoshi Ishikawa, Yamaguchi Tadashi, T. Takashi Tomokuni, Hirotoshi Morii, and T. Kenji Moriya
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medicine.medical_specialty ,endocrine system diseases ,medicine.drug_class ,Parathyroid hormone ,Sevelamer ,Gastroenterology ,Hyperphosphatemia ,chemistry.chemical_compound ,Renal Dialysis ,Calcium Metabolism Disorders ,Internal medicine ,medicine ,Humans ,Vitamin D ,Osteomalacia ,Hyperparathyroidism ,business.industry ,nutritional and metabolic diseases ,Alfacalcidol ,medicine.disease ,Phosphate binder ,Endocrinology ,Hypoparathyroidism ,chemistry ,Nephrology ,Bone Diseases ,business ,medicine.drug - Abstract
In chronic renal failure, hyperphosphatemia, hypocalcemia, hyperparathyroidism, reduced activation of vitamin D, decreased level of calcium-sensing receptor, osteitis fibrosa, and osteomalacia are features related to calcium abnormalities. Hyperparathyroidism is a risk factor for survival of hemodialysis patients as well as hypoparathyroidism, which is another feature in hemodialysis patients. Treatment of these abnormalities includes control of parathyroid hormone (PTH) secretion, counteracting hyperphosphatemia, correction of hypocalcemia, and others. Various kinds of vitamin D analogs have been introduced recently in addition to calcitriol and alfacalcidol, which have a rather long history (eg, maxacalcitol and falecalcitriol). Sevelamer is a newly developed phosphate binder to treat soft-tissue calcification.
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- 2004
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41. High incidence of ultraviolet-B-or chemical-carcinogen-induced skin tumours in mice lacking the xeroderma pigmentosum group A gene
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Takeshi Horio, Osamu Nikaido, Yukihiko Kitamura, Kiyoji Tanaka, Shunsuke Yuba, Seiichi Hirota, Yoko Nakatsuru, Tomoyuki Tokunaga, Yoshimichi Nakatsu, Yoko Kato, Yukio Tsunoda, Tsukasa Matsunaga, Yoshitake Nishimune, Seiji Takeuchi, Hiroko Miyauchi, Takatoshi Ishikawa, Masafumi Saijo, Yoshio Okada, Hiroaki Murai, and Hironobu Nakane
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Male ,Neoplasms, Radiation-Induced ,Skin Neoplasms ,Xeroderma pigmentosum ,DNA Repair ,Ultraviolet Rays ,9,10-Dimethyl-1,2-benzanthracene ,Biology ,medicine.disease_cause ,Group A ,Cell Line ,Mice ,In vivo ,medicine ,Animals ,Cloning, Molecular ,Gene ,Genetics ,Xeroderma Pigmentosum ,Multidisciplinary ,integumentary system ,Incidence ,Gene targeting ,medicine.disease ,Xeroderma Pigmentosum Group A Protein ,DNA-Binding Proteins ,Mice, Inbred C57BL ,Complementation ,Gene Targeting ,Mice, Inbred CBA ,Cancer research ,Female ,Skin cancer ,Carcinogenesis ,Gene Deletion - Abstract
Xeroderma pigmentosum (XP) is an autosomal recessive disorder characterized by a high frequency of skin cancer on sun-exposed areas, and neurological complications. XP has a defect in the early step(s) of nucleotide-excision repair (NER) and consists of eight different genetic complementation groups (groups A-G and a variant). We established XPA (group-A XP) gene-deficient mice by gene targeting of mouse embryonic stem (ES) cells. The XPA-deficient mice showed neither obvious physical abnormalities nor pathological alterations, but were defective in NER and highly susceptible to ultraviolet-B- or 9,10-dimethyl-1,2-benz[a]anthracene-induced skin carcinogenesis. These findings provide in vivo evidence that the XPA protein protects mice from carcinogenesis initiated by ultraviolet or chemical carcinogen. The XPA-deficient mice may provide a good in vivo model to study the high incidence of skin carcinogenesis in group A XP patients.
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- 1995
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42. Aortic arch malformations and ventricular septal defect in mice deficient in endothelin-1
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Takatoshi Ishikawa, Yukiko Kurihara, Kouji Maemura, Yoshio Yazaki, Ryozo Nagai, H. Kurihara, and Hideaki Oda
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Heart Septal Defects, Ventricular ,medicine.hormone ,Aortic arch ,medicine.medical_specialty ,Pathology ,Gene Expression ,Aorta, Thoracic ,Biology ,Endothelins ,Mice ,Internal medicine ,medicine.artery ,medicine ,Animals ,Thoracic aorta ,Mice, Inbred ICR ,Aorta ,Interrupted aortic arch ,Antibodies, Monoclonal ,General Medicine ,medicine.disease ,Endothelin 1 ,Hypoplasia ,medicine.anatomical_structure ,cardiovascular system ,Cardiology ,Pharyngeal arch ,Research Article - Abstract
Endothelin-1 (ET-1) is a 21-amino acid peptide with various biological activities including vasoconstriction and cell proliferation. To clarify the physiological and pathophysiological role of ET-1, we disrupted the mouse Edn1 locus encoding ET-1 by gene targeting and demonstrated that ET-1 is essential to the normal development of pharyngeal arch-derived tissues and organs. In this study, we focused on the phenotypic manifestations of Edn1-/- homozygous mice in the cardiovascular system. Edn1-/- homozygotes display cardiovascular malformations including interrupted aortic arch (2.3%), tubular hypoplasia of the aortic arch (4.6%), aberrant right subclavian artery (12.9%), and ventricular septal defect with abnormalities of the outflow tract (48.4%). The frequency and extent of these abnormalities are increased by treatment with neutralizing monoclonal antibodies or a selective ETA receptor antagonist BQ123. At an earlier embryonic stage, formation of pharyngeal arch arteries and endocardial cushion is disturbed in Edn1-/- homozygotes. In situ hybridization confirmed ET-1 expression in the endothelium of the arch arteries and cardiac outflow tract and the endocardial cushion as well as in the epithelium of the pharyngeal arches. Thus, ET-1 is involved in the normal development of the heart and great vessels, and circulating ET-1 and/or other ET isoforms may cause a functional redundancy, at least partly, through the ETA receptor.
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- 1995
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43. A polymorphism at codon 160 of human O6 methylguanine-DNA methyltransferase gene in young patients with adult type cancers and functional assay
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Hideaki Oda, Yasuo Imai, Yoko Nakatsuru, and Takatoshi Ishikawa
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Adult ,Male ,Cancer Research ,Carcinoma, Hepatocellular ,Adolescent ,DNA damage ,DNA repair ,Molecular Sequence Data ,Glycine ,Biology ,Gene mutation ,Arginine ,Kidney ,medicine.disease_cause ,Polymerase Chain Reaction ,Cholangiocarcinoma ,O(6)-Methylguanine-DNA Methyltransferase ,Reference Values ,Stomach Neoplasms ,medicine ,Humans ,Point Mutation ,Cysteine ,Child ,Codon ,Aged ,DNA Primers ,Aged, 80 and over ,Polymorphism, Genetic ,Base Sequence ,Point mutation ,Liver Neoplasms ,O-6-methylguanine-DNA methyltransferase ,Exons ,Methyltransferases ,General Medicine ,Middle Aged ,Molecular biology ,Female ,DNA mismatch repair ,Carcinogenesis ,Spleen ,Nucleotide excision repair - Abstract
O6-methylguanine-DNA methyltransferase (MGMT) plays an important role in repair of alkylating agent-induced DNA damage. Among the alkylation products of DNA, O6-methylguanine is one of the most critical lesions leading to the induction of mutations. The enzyme MGMT transfers the methyl group from O6-methylguanine of DNA to its own cysteine residue. Although mutations of other DNA repair genes involved in nucleotide excision repair and mismatch repair have been proven to be related to human tumorigenesis, the question of whether MGMT gene mutation might play a role in human carcinogenesis has hitherto not been elucidated. If there is a population with decreased enzyme activity due to defective MGMT gene, the affected individuals should be at risk of developing cancer early in life because of an increased susceptibility to alkylating agents. To test this hypothesis, germ line mutations of the MGMT gene were investigated in 12 young patients with adult type cancers (mean, 16.7 years old, 8 hepatocellular carcinomas, 3 gastric cancers, 1 cholangiocellular carcinoma) and 28 elderly patients who died of non-cancer diseases as controls (mean, 66 years old). A point mutation at codon 160 in exon 5, GGA to AGA, converting glycine to arginine was found in three of the young patients (25%), while the same mutation was found in three out of 28 (10.7%) in the control group. The mutated codon was located 15 codons from a functional cysteine residue toward the carboxyl terminal. Investigation of enzyme function, even in cases of bi-allelic mutation, revealed comparable activities for both mutated and wild type MGMT. Thus, we conclude the mutation is a normal polymorphism of the MGMT gene, present in approximately 15% of the population, although this does not rule out a possible influence in other tissues.
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- 1995
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44. Quantitative Detection of Ultraviolet Light‐induced Photoproducts in Mouse Skin by Immunohistochemistry
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Seiichiro Shimizu, Osamu Nikaido, Yukari Yamazaki, Xiusheng Qin, Takatoshi Ishikawa, Hideaki Oda, Shaomin Zhang, and Yoko Nakatsuru
- Subjects
Cancer Research ,DNA Repair ,DNA damage ,DNA repair ,Photochemistry ,Ultraviolet Rays ,Color ,Pyrimidine dimer ,Biology ,Article ,Cyclobutane ,Immunoenzyme Techniques ,chemistry.chemical_compound ,Mice ,In vivo ,Ultraviolet light ,Image Processing, Computer-Assisted ,Animals ,Skin ,Mice, Inbred C3H ,Epidermis (botany) ,integumentary system ,Mouse skin ,DNA ,Fibroblasts ,Molecular biology ,Immunohistochemistry ,Staining ,Oncology ,chemistry ,Pyrimidine Dimers ,Female ,sense organs ,Epidermis ,UV‐photoproduct DNA repair ,Cell Division ,DNA Damage - Abstract
UVB-induced cyclobutane pyrimidine dimers (CPDs) and pyrimidine-pyrimidone (6-4)photoproducts [(6-4)photoproducts] in mouse skin DNA were quantitatively measured using an immunohistochemical approach with a computer-aided color image analyzer. The skins of the C3H/HeN mice were irradiated with ultraviolet B (UV-B, 280-320 nm), and processed to give conventional formalin-fixed, paraffin-embedded histologic sections. Routine immunohistochemistry clearly demonstrated a dose-dependent induction of both photoproducts. CPDs were detectable at doses > or = 125 J/m2, while for (6-4)photoproducts, the minimal dose at which they were detectable was 250 J/m2 in the present study. A time course study showed that the repair of (6-4)photoproducts was more rapid than that of CPDs, and that epidermal cells had a higher capacity for their removal than dermal cells. About half of the (6-4)photoproducts were excised within the first 24 h after the irradiation, and the process was essentially complete by 72 h. In contrast, there was no apparent removal (less than 10%) of CPDs in the first 24 h and they only completely disappeared from the epidermal cells at 120 h after irradiation. The effect of DNA dilution due to increased turnover of epidermal cells after UV-B irradiation was evaluated by quantitative immunohistochemical measurement of the time course of bromodeoxy-uridine (BrdUrd) incorporated into nuclei at 2 days post irradiation when the proliferation reaches a peak. The removal of photoproducts was more marked than the decrease in BrdUrd staining. Our results suggest that mouse skin cells can repair both (6-4)photoproducts and CPDs, but with considerably lower efficiency, especially in the latter case, then human or monkey skin cells.
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- 1995
45. New Flipchip Technology
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Takatoshi Ishikawa and Reinhard Windemuth
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Printed circuit board ,Engineering ,Interconnection ,Reliability (semiconductor) ,Packaging engineering ,business.industry ,Process (engineering) ,Mechanical engineering ,Process window ,business ,Chip ,Manufacturing engineering ,Flip chip - Abstract
Flipchip Technology is getting more and more important for future packaging solutions. This presentation gives an overview of different Flipchip Technology Solutions provided by industry. Mainstream Technologies such as C4 and ACF / ACP processes are explained. In special focus will be recently developed new processes to improve: Thermosonic Gold to Gold Interconnect (GGI) Process and Encapsulant Solder Connect (ESC) Process. Those being very fast and highly reliable. This is why they are suitable for further future miniturization. They cover a wide range of industries product applications. Typical characteristics and process parameters for ESC and GGI will be described and analysed. Reliability data will be shown and explained. Both processes are suitable to be used in Chip on Board (COB), Waferlevel (COW) and Embedded Packaging Technology & Assembly. Some examples of how to use Flipchip processes for embedding active components to FR4 Printed Circuit boards (PCB) are shown and explained.
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- 2012
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46. Antiplatelet Agents Based on Cyclooxygenase Inhibition without Ulcerogenesis. Evaluation and Synthesis of 4,5-Bis(4-methoxyphenyl)-2-substituted-thiazoles
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Yukio Motoyama, Hisashi Takasugi, Akito Tanaka, Takatoshi Ishikawa, and Hiroyoshi Sakai
- Subjects
Blood Platelets ,Male ,Platelet Aggregation ,Side effect ,Stereochemistry ,Guinea Pigs ,Pharmacology ,Piperazines ,Rats, Sprague-Dawley ,Structure-Activity Relationship ,chemistry.chemical_compound ,Oral administration ,Malondialdehyde ,Drug Discovery ,Animals ,Cyclooxygenase Inhibitors ,Platelet ,Stomach Ulcer ,IC50 ,Molecular Structure ,biology ,Rats ,Vasodilation ,Thiazoles ,chemistry ,biology.protein ,Molecular Medicine ,Arachidonic acid ,Rabbits ,Cyclooxygenase ,Platelet Aggregation Inhibitors ,Ex vivo - Abstract
The syntheses, biological evaluations, and structure-activity relationships of a series of 4,5-bis-(4-methoxyphenyl)-2-substituted-thiazoles as potent antiplatelet agents with vasodilatory activity are described. 2-Guanidino-4,5-bis(4-methoxyphenyl)thiazole (3), designed from two parent compounds (itazigrel and timegadine), showed inhibitory activity of malondialdehyde (MDA, IC50 = 31 microM) production which is formed from the cyclooxygenase (CO)-catalyzed oxygenation of arachidonic acid in the synthesis of prostanoids in platelets, with vasodilatory activity (ED50 = 2.0 microM). Further structure-activity relationship studies on 3 culminated in the preparation of 4,5-bis(4-methoxyphenyl)-2-[(1-methylpiperazin-4-yl)carbonyl]thiaz ole (10a, FR122047) which exhibited potent inhibitory activity on MDA synthesis in vitro (IC50 = 0.088 microM) and platelet aggregation in guinea pigs ex vivo (100% inhibition even 6 h after 1.0 mg/kg administration) with vasodilatory activity in vitro (ED50 = 6.2 microM). Moreover, 10a demonstrated no ulcerogenesis effect in rats even at 100 mg/kg dosage (safety margin in rats is more than 70 while that of aspirin is only 1.2) in spite of its potent CO inhibition (IC50 = 0.43 microM14), while the use of aspirin, a CO inhibitor and the most popular thromboembolic drug, is restricted by the side effect. Pharmacokinetic studies on 10a have revealed that 10a is detectable in platelet-rich plasma but not in platelet-poor plasma 1 day after oral administration, which indicates that 10a tends to be localized in platelets. This property could be responsible for its low toxicity and reduction of side effects in clinical studies.
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- 1994
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47. Cloning and activation of the Syrian hamster neu proto-oncogene
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Minako Nagao, Takatoshi Ishikawa, Arai M, Toshikazu Nakamura, Yukihito Ishizaka, Toshikazu Ushijima, and Yamazaki Y
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Receptor, ErbB-2 ,Molecular Sequence Data ,Hamster ,Biology ,Transfection ,Proto-Oncogene Mas ,Gene product ,Mice ,Transformation, Genetic ,ErbB ,Cricetinae ,Proto-Oncogene Proteins ,Sequence Homology, Nucleic Acid ,Complementary DNA ,Proto-Oncogenes ,Genetics ,Animals ,Humans ,Amino Acid Sequence ,Cloning, Molecular ,Phosphorylation ,Base Sequence ,Mesocricetus ,Sequence Homology, Amino Acid ,cDNA library ,Point mutation ,Autophosphorylation ,3T3 Cells ,General Medicine ,Molecular biology ,Rats ,ErbB Receptors ,Transmembrane domain ,Gene Expression Regulation ,Tyrosine - Abstract
Point mutations of the Syrian hamster neu proto-oncogene have been observed in the transmembrane domain of N -nitroso- N -ethylurea(ENU)-induced neurofibromas, Genomic DNA derived from tumor tissue showed transforming activity in an NIH 3T3 assay and a cDNA clone of the hamster neu gene, containing the entire protein-coding region, was isolated from a transformant cDNA library. The encoded product is 92 and 88% homologous to the rat neu and the human c - erbB -2, respectively. The product of the mutated hamster neu gene showed increased autophosphorylation of Tyr residues.
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- 1994
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48. DNA adduct formation and assessment of aberrant crypt foci in vivo in the rat colon mucosa after treatment with N-methyl-N-nitrosourea
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Yoko Nakatsuru, Xiusheng Qin, Masami Arai, Hideaki Oda, Takatoshi Ishikawa, and Mirjana Zarkovic
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Male ,Cancer Research ,Pathology ,medicine.medical_specialty ,Guanine ,Time Factors ,Nitrosourea Compound ,Colon ,Colon mucosa ,Tritium ,digestive system ,Adduct ,chemistry.chemical_compound ,In vivo ,medicine ,Animals ,DNA Adduct Formation ,Intestinal Mucosa ,Carcinogen ,Dose-Response Relationship, Drug ,Chemistry ,Methylnitrosourea ,DNA ,General Medicine ,Molecular biology ,Rats, Inbred F344 ,digestive system diseases ,Rats ,Colonic Neoplasms ,Aberrant crypt foci - Abstract
N-Nitroso-compound DNA adduct formation in vivo and occurrence of aberrant crypt foci (ACF) were studied in the rat colon mucosa after a single, local treatment with a carcinogen, N-methyl-N-nitrosourea (MNU), using a simple surgical approach. A segment of F344 rat colon was ligated to make a pouch and injected with MNU solution. For the study of DNA adduct formation, the solution contained 50 microCi of [3H]MNU. The results demonstrated that similar ranges of carcinogen dose, i.e. 0.15 x 10(-2) - 1.5 x 10(-2) M MNU, could induce both DNA adduct formation and appearance of ACF in the rat colon with both parameters showing a nearly linear dose dependence. HPLC analysis revealed the DNA adducts to include both 7-methylguanine (7-mGua) and O6-methylguanine (O6-mGua) with the 7-mGua/O6-mGua ratio being 8.2-11.3:1 in the system used. Assessment of ACF development from 4 to 16 weeks after MNU treatment at a dose of 7.5 x 10(-2) M showed the numbers to increase up to the 8th week, followed by a decrease at weeks 12 and 16, when 40% of the ACF counted at the peak time point were still present. The percentage of large ACF (> or = 4 crypts/ACF) significantly increased with time. These results indicate a clear relation between DNA adducts and preneoplastic lesions, i.e. ACF. In conclusion, DNA adduct formation and ACF can be efficiently and simply detected in vivo by using the method described in the present paper.
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- 1994
- Full Text
- View/download PDF
49. O6-Methylguanine-DNA Methyltransferase Activity in the Human Lung Persists with Advancing Age
- Author
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Ken Nakagawa, Hideaki Oda, Yoko Nakatsuru, Nobuo Nemoto, Eiju Tsuchiya, and Takatoshi Ishikawa
- Subjects
Senescence ,Aging ,Lung ,Methyltransferase ,DNA repair ,Physiology ,O-6-methylguanine-DNA methyltransferase ,Biology ,medicine.disease ,digestive system diseases ,medicine.anatomical_structure ,Carcinoma ,medicine ,Cancer research ,Geriatrics and Gerontology ,Lung cancer ,neoplasms ,Carcinogen - Abstract
O6-methylguanine-DNA methyltransferase (MGMT) plays an important role in the repair of DNA lesions induced by alkylating carcinogens in a wide range of animals. To determine the relationship between DNA repair activity and tumor susceptibility with advancing age the activity of MGMT was measured in normal lung tissue extracts from 66 patients with primary or metastatic lung cancer obtained at surgery. The age of the patients whose lung MGMT activity was measured ranged from 40 to 79 years (males) and from 40 to 80 years (females), and the values varied over 10-fold in both sexes (33 males and 33 females). Our results indicate that the MGMT enzyme protein is expressed at appreciable levels throughout life, and on age-associated rapid decline is not a feature in the human lung. Thus, any age-associated increase in lung cancer incidence cannot be ascribed to any change in MGMT activity. In order to assess other possible factors which might exert a modulating influence we examined the MGMT activity in relation to sex, tumor type and smoking. However, in none of these cases was any significant correlation evident.
- Published
- 1994
- Full Text
- View/download PDF
50. Title Page / Table of Contents, Supplement 2, 1994
- Author
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Isao Kato, Haruyasu Yamaguchi, Masatoshi Fujishima, Shunsaku Hirai, Takatoshi Ishikawa, Yoshiaki Komiya, Kenji Toba, Kei Maruyama, Takaaki Hasegawa, Hideaki Oda, Hideo Kawano, Yutaka Kiyohara, Ken Nakagawa, Seikoh Horiuchi, Eiju Tsuchiya, Yasuhide Nakashima, Taketo Yoshitake, Norie Araki, Nobuo Nemoto, Tsuneo Yamazaki, Kazuyuki Fuji, Thomas N. Tulenko, Xaoyan Sun, Yoshihiro Kumagae, Atsumi Nitta, Kazuhito Yamashita, Mihoko Usami, Yasuyoshi Ouchi, Shoichi Ishiura, Yasujirou Sakai, Tsuyoshi Kawarabayashi, Jing Liang, Yumiko Saito, Hiromi Tasaki, Kunihiko Obata, Yoko Nakatsuru, Toshitaka Nabeshima, Takao Ohmura, Tomoko Tashiro, Kazuo Ueda, Masahiro Akishita, Wakako Yamao-Harigaya, Seiichi Kawashima, Hajime Orimo, Tsutomu Kameyama, and Akio Kuroiwa
- Subjects
Aging ,media_common.quotation_subject ,Library science ,Table of contents ,Art ,Geriatrics and Gerontology ,Title page ,media_common - Published
- 1994
- Full Text
- View/download PDF
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