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Expression of the Japanese oak silkworm Antheraea yamamai fibroin gene in the domesticated silkworm Bombyx mori

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Insect Science 2009年第6期16卷 465-473页

作者： Isao Kobayashi Katsura Kojima Hideki Sezutsu Keiro Uchino Toshiki tamura Transgenic Silkworm Research Center Silk Materials Research Unit National Institute of Agrobiological Sciences Ibaraki Japan

To understand the evolutionary conservation ofthe gene expression mechanism and secretion machinery between Antheraea and Bombyx fibroins, we introduced the genomic A. yamamai fibroin gene into the domesticated silkworm, B. mori. The spliced A. yamamai fibroin mRNA appeared only in the posterior region of the silk gland of the transgenic silkworm, suggesting that the functions of the fibroin promoter region and the splicing machinery are conserved between these two species. The A. yamarnai fibroin protein was detected in the lumen of the silk gland of the transgenic silkworm, albeit at lower levels compared with the B. mori-type fibroin. We found a strong degeneration of the posterior region of the silk gland of the transgenic silkworm. As a result, the cocoon shell weight was much lower in the transgenic silkworm than in the non-transgenic line. These results indicate that the promoter function and splicing machinery are well conserved between A. yamamai and B. mori but that the secretion mechanism of fibroin is diversified between the two.

关键词： Antheraea yamamai Bombyx mori evolution fibroin silk transgenic

Preliminary Study to Identify Criterion for Quench Crack Prevention by Computer Simulation

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材料热处理学报 2004年第5期25卷 486-493页

作者： Kyozo Arimoto Fumiaki Ikuta Takashi Horino Shigeyuki tamura Michiharu Narazaki Yoshio Mikita Arimotech Ltd. Osaka Japan Neturen Co. Ltd. Kanagawa JapanNeturen Co. Ltd. Kanagawa JapanCRC Solutions Corp. Tokyo JapanUtsunomiya University Utsunomiya JapanMIKITA Professional Engineer Office Tokushima Japan

A criterion for preventing quench cracks has not been established although much research has been conducted in this field. A few predictions of cracking have been recently reported using simulated results of heat treatment processes. However, these results were insufficient to predict crack generation clearly because the mechanism relates not only to stress distributions in the parts but also to material characteristics. Systematic studies by the combination of experiment and simulation are therefore required to reliably identify a criterion for crack prevention by computer simulation. As a preliminary work before starting the full-scale research, a review of quench cracking research was conducted and existing test methods were classified. Several test results for cylindrical specimens were simulated for considering a cause of the crack generation. Lastly a tentative plan was made for the future research.

关键词：淬火裂纹热处理计算机模拟防止方法

Microstructure formation and grain refinement of Mg-based alloys by electromagnetic vibration technique

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Transactions of Nonferrous Metals Society of China 2010年第7期20卷 1192-1198页

作者： M.J.LI T.tamura N.OMURA K.MIWA National Institute of Advanced Industrial Science and Technology Materials Research Institute for Sustainable DevelopmentNagoya 463-8560Japan

The microstructure formation and grains refinement of two Mg-based alloys,***31 and AZ91D,were reported using an electromagnetic vibration(EMV) *** two alloys were solidified at various vibration frequencies and the microstructures were *** average size of grains was quantitatively measured as a function of vibration frequencies. Moreover,the grain size distribution was outlined versus number fraction.A novel model was proposed to account for the microstructure formation and grain refinement when considering the significant difference of the electrical resistivity properties of the solid and the liquid during EMV processing in the semisolid *** remarkable difference originates uncoupled movement between the mobile solid and the sluggish liquid,which can activate melt *** microstructure evolution can be well explained when the fluid flow intensity versus vibration frequency is taken into ***,the influence of the static magnetic field on texture formation is also considered,which plays an important role at higher vibration frequencies.

关键词： magnesium alloy electromagnetic vibration microstructure formation grain refinement solidification

Hot-Dip Coating of Lead-free Aluminum on Steel Substrates with Ultrasonic Vibration

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Journal of Materials Science & Technology 2008年第1期24卷 41-44页

作者： Y. Tsunekawa S. tamura M. Okumiya N.Ishihara Toyota Technological Institute Tempaku Nagoya 468-8511 Japan

Hot-dip coating has been practically employed in manufacturing zinc alloy coated steel ***,it is difficult to coat aluminum alloy on a bulky steel substrate without sufficient preheating,because a rapidly solidified layer containing gas babbles is formed on a substrate surface.A variety of iron-aluminides are also formed at the interface of a steel and aluminum hot-dip coating system,which is the main difficulty in joining of steel with *** vibration was applied to a steel substrate during hot-dip coating of aluminum alloy to control a rapidly solidified layer and a brittle reaction *** dipping of columnar steel substrates into molten aluminum alloy （Al-2.7 mass fraction Si-4.6 mass fraction Sn） was carried out through the use of a Langevin oscillator with resonant frequency of 19.5 *** application of ultrasonic vibration is quite effective to control a rapidly solidified layer and a surface oxide layer from a substrate surface by the sonocapillary effect based on a cavitation phenomenon,so that the intimate contact is achieved at the beginning of hot-dip *** application of ultrasonic vibration to hot-dipping is effective to control a reaction layer with less than 5 #m in *** impact test exhibits that the good adhesive strength is approved in hot-dipped aluminum coatings with a thin reaction layer of approximately 5μm.

关键词： Ultrasonic vibration Cavitation Sono-Capillary effect Hot-dip coating

Porphyromonas gingivalis,a periodontal pathogen,impairs post-infarcted myocardium by inhibiting autophagosome–lysosome fusion

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International Journal of Oral Science 2023年第4期15卷 626-639页

作者： Yuka Shiheido-Watanabe Yasuhiro Maejima Shun Nakagama Qintao Fan Natsuko tamura Tetsuo Sasano Department of Cardiovascular Medicine Graduate School of Medical and Dental SciencesTokyo Medical and Dental UniversityTokyoJapan

While several previous studies have indicated the link between periodontal disease (PD) and myocardial infarction (MI), theunderlying mechanisms remain unclear. Autophagy, a cellular quality control process that is activated in several diseases, includingheart failure, can be suppressed by Porphyromonas gingivalis (P.g.). However, it is uncertain whether autophagy impairment byperiodontal pathogens stimulates the development of cardiac dysfunction after MI. Thus, this study aimed to investigate therelationship between PD and the development of MI while focusing on the role of autophagy. Neonatal rat cardiomyocytes(NRCMs) and MI model mice were inoculated with wild-type P.g. or gingipain-deficient P.g. to assess the effect of autophagyinhibition by P.g. Wild-type P.g.-inoculated NRCMs had lower cell viability than those inoculated with gingipain-deficient P.g. Thisstudy also revealed that gingipains can cleave vesicle-associated membrane protein 8 (VAMP8), a protein involved in lysosomalsensitive factor attachment protein receptors (SNAREs), at the 47th lysine residue, thereby inhibiting autophagy. Wild-type P.g.-inoculated MI model mice were more susceptible to cardiac rupture, with lower survival rates and autophagy activity thangingipain-deficient P.g.-inoculated MI model mice. After inoculating genetically modified MI model mice (VAMP8-K47A) with wildtype P.g., they exhibited significantly increased autophagy activation compared with the MI model mice inoculated with wild-typeP.g., which suppressed cardiac rupture and enhanced overall survival rates. These findings suggest that gingipains, which arevirulence factors of P.g., impair the infarcted myocardium by cleaving VAMP8 and disrupting autophagy. This study confirms thestrong association between PD and MI and provides new insights into the potential role of autophagy in this relationship.

关键词： inhibiting myocardium periodontal

Enzymatic treatment of estrogens and estrogen glucuronide

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Journal of Environmental Sciences 2009年第6期21卷 731-735页

作者： Takaaki Tanaka Toshiyuki tamura Yuuichi Ishizaki Akito Kawasaki Tomokazu Kawase Masahiro Teraguchi Masayuki Taniguchi Department of Materials Science and Technology Niigata University Venture Business Laboratory Niigata University Department of Chemistry and Chemical Engineering Niigata University

Natural and synthetic estrogens from sewage treatment systems are suspected to influence the reproductive health of the animals in the rivers. In this article, we investigated the enzymatic treatment of three estrogens （estrone, 17β-estradiol, and 17α-ethynyletstradiol） by a fungal laccase which oxidize phenolic compounds with dissolved oxygen. The elimination of the estrogenic activities by enzymatic oxidation was demonstrated by medaka vitellogenin assay. In addition, we developed an enzymatic treatment system comprised of β-D-glucuronidase and the laccase for 17β-estradiol 3-（β-D-glucuronide） degradation. The two enzymes eliminated 17β-estradiol 3-（β- D-glucuronide） and the intermediate, 17β-estradiol, efficiently.

关键词： enzymatic treatment laccase estrone estradiol ethynylestradiol glucuronidase glucuronide

Diagnosis and management of pancreatic neuroendocrine tumor in von Hippel-Lindau disease

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World Journal of Gastroenterology 2010年第36期16卷 4515-4518页

作者： Kenji tamura Isao Nishimori Tetsuhide Ito Ichiro Yamasaki Hisato Igarashi Taro Shuin Department of Urology Kochi Medical SchoolNankokuKochi 783-8505Japan Nishimori's Clinic SakawaKochi 789-1233Japan Department of Medicine and Bioregulatory Science Graduate School of Medical SciencesKyushu UniversityHigashi-kuFukuoka 812-8582Japan

The pancreatic manifestations seen in patients with von Hippel-Lindau(VHL) disease are subdivided into 2 categories:pancreatic neuroendocrine tumors(NET),and cystic lesions,including simple cyst and serous *** VHL-associated cystic lesions are generally asymptomatic and do not require any treatment,unless they are indistinguishable from other cystic tumor types with malignant *** pancreatic NET in VHL disease are non-functioning and have malignant potential,it is of clinical importance to find and diagnose these as early as *** will be recommended that comprehensive surveillance using dynamic computed tomography for abdominal manifestations,including pancreatic NET,should start from the age of 15 years in VHL *** sporadic non-functioning NET without VHL disease,in which surgical resection is generally recommended,VHL patients at lower metastatic risk of pancreatic NET should be spared the risks of operative resection.

关键词： Von Hippel-Lindau disease Pancreas Neuroendocrine tumor,Diagnosis Clinical protocols

Efficacy of mycofenolate mofetil for steroid-resistant acute rejection after living donor liver transplantation

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World Journal of Gastroenterology 2006年第30期12卷 4870-4872页

作者： Nobuhisa Akamatsu Yasuhiko Sugawara Sumihito tamura Yuichi Matsui Junichi Kaneko Masatoshi Makuuchi Artificial Organ and Transplantation Surgery Division Department of Surgery University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-8655Japan

AIM： To discuss the use of mycophenolate mofetil （MMF） as an immunosuppressant in steroid resistant rejection after liver transplantation. METHODS： The clinical records of 260 adult patients who underwent living donor liver transplantation （LDLT） were reviewed. Tacrolimus and methylprednisolone were used for primary immunosuppression. Acute rejection was first treated with steroids. When steroid resistance occurred, the patient was treated with a combination of steroids and MMF. Anti-T-cell monoclonal antibody was administered to patients who were not responsive to steroids in combination with MMF.RESULTS： A total of 90 （35%） patients developed acute rejection. The median interval time from transplantation to the first episode was 15 d. Fifty-four patients were steroid resistant. Forty-four patients were treated with MMF and the remaining 10 required anti-T-cell monoclonal antibody treatment. Progression to chronic rejection was observed in one patient. Bone marrow suppression and gastrointestinal symptoms were the most common side effects associated with MMF use. There was no significant increase in opportunistic infections. CONCLUSION： Our results demonstrate that MMF is a potent and safe immunosuppressive agent for rescue therapy in patients with acute rejection after LDLT.

关键词： Tacrolimus Rejection Liver transplantation

Jurassic-Cretaceous Boundary Strata of the Somanakamura Group in NE Japan and their Correlation with Coeval Terrestrial Deposits in China

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 285-299页

作者： LI Wei WAN Xiaoqiao Atsushi MATSUOKA ZHANG Shuqin QU Haiying Tsubasa tamura Kohei YOSHINO State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Department of Geology Niigata University Research Center of Paleontology and Stratigraphy Jilin Univercity

Defining the Jurassic-Cretaceous boundary is a controversy in stratigraphic study of the world. It has been widely accepted that this boundary can be defined at the bottom of Berriasian in Tetbys, with the appearance of the ammonite Berriasellajacobi dating to ca. 145 Ma. However, it is difficult for the widespread terrestrial deposits in China to correlate with the international standard of marine facies. The Somanakamura Group in Japan is represented by a succession of marinecontinental transitional strata. It provides a bridge of marine and nonmarine stratigraphic correlation. The ammonite and radiolarian fossils preserved in this group suggest an age from Bajocian to early Valanginian. The J-K boundary was defined in or atop the Tomizawa Formation of the group according to the ammonite data. The present authors study the fossil spores and pollen newly found from the Tomizawa and Koyamada formations. Three assemblages have been recognized. They are Assemblage 1 （Cyathidites-Classopollis） from the upper part of the Tomizawa Formation, Assemblage 2 （Cyathidites-Jiaohepollis） from the lower part of the Koyamada Formation, and Assemblage 3 （Cyathidites-Spheripollenites-Ephedripites） from the middle to upper part of the Koyamada Formation. With the reference of ammonite evidence, the J-K boundary can be defined between Assemblage 1 and Assemblage 2. This palynological J-K boundary can be correlated with that of terrestrial sequence in China. However, local biostratigraphy imply that the continental J-K boundary in China is of 135 or 137 Ma age. It has a considerable discrepancy from the marine standard. Biogeographically, the distribution pattern of spores and pollen in southern China is in accordance with that in the Somanakamura Group, which parallels the Tuchengzi Formation in northeastern China. By the palynological correlation between the Somanakamura Group and the strata in southern China, and then with the sequence in northeastern China, it is suggested that th

关键词： Somanakamura Group Jurassic-Cretaceous boundary ammonites spores and pollen,Tomizawa Formation Koyamada Formation Tuchengzi Formation