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Distribution and relative activity of matrix metalloproteinase-2 in human coronal dentin

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International Journal of Oral Science 2011年第4期3卷 192-199页

作者： Lee W. Boushell Masaru Kaku Yoshiyuki Mochida Mitsuo yamauchi Department of Operative Dentistry School of Dentistry University of North Carolina Department of Bio-Prosthodontics Medical and Dental Science Niigata University Graduate School Chuo-ku Department of Periodontology and Oral Biology Division of Oral Biology Boston University Henry M. Goldman School of Dental Medicine Center for Advanced Biomedical Research Dental Research Center School of Dentistry University of North Carolina

The presence of matrix metalloproteinase-2 （MMP-2） in dentin has been reported, but its distribution and activity level in mature human coronal dentin are not well understood. The purpose of this study was to determine the MMP-2 distribution and relative activity in demineralized dentin. Crowns of twenty eight human molars were sectioned into inner （ID）, middle （MD）, and outer dentin （OD） regions and demineralized. MMP-2 was extracted with 0.33 mol·L-1 EDTA/2 mol·L-1 guanidine-HCl, pH 7.4, and MMP-2 concentration was estimated with enzyme-linked immunoabsorbant assay （ELISA）. Further characterization was accomplished by Western blotting analysis and gelatin zymography. The mean concentrations of MMP-2 per mg dentin protein in the dentin regions were significantly different （P=0.043）： 0.9 ng （ID）, 0.4 ng （MD）, and 2.2 ng （OD）, respectively. The pattern of MMP-2 concentration was OD〉ID〉MD. Western blotting analysis detected -66 and -72 kDa immunopositive proteins corresponding to pro- and mature MMP-2, respectively, in the ID and MD, and a -66 kDa protein in the OD. Gelatinolytic activity consistent with MMP-2 was detected in all regions. Interestingly, the pattern of levels of Western blot immunodetection and gelatinolytic activity was MD〉ID〉OD. The eoneentration of MMP-2 in human coronal dentin was highest in the region of dentin that contains the dentinoenamel junction and least in the middle region of dentin. However, levels of Western blot immunodetection and gelatinolytic activity did not correlate with the estimated regional concentrations of MMP-2, potentially indicating region specific protein interactions.

关键词： matrix metalloproteinase-2 human coronal dentin distribution gelatinolytic activity

Investigation on Retention and Release Behaviors of Hydrogen and Helium in Vanadium Alloy

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Plasma Science and Technology 2005年第3期7卷 2835-2838页

作者：刘翔 Tsuyoshi Yamada Yuji yamauchi Yuko Hirohata Tomoaki Hino Nobuaki Noda Southwestern Institute of Physics Chengdu 610041 China Laboratory of Plasma Physics and Engineering Hokkaido UniversityKita-13 Nishi-8 Kita-ku Sapporo 060-8628 Japan National Institute for Fusion Science Toki-shi Gifu-ken 509-5202 Japan

Vanadium alloy is proposed as an attractive candidate for first wall and blanket structural material of fusion reactors. The retention and release behaviors of hydrogen and helium in vanadium alloy may be an important issue. In the present work, 1.7 keV deuterium and 5 keV helium ions are respectively implanted into V-4Cr-4Ti and V-4Ti at room temperature. The retention and release of deuterium and helium are measured with thermal desorption spectroscopy (TDS). When the helium ion fluence is larger than 3 × 1017 He/cm2, the retained helium saturates with a value of approximately 2.5 ×1017 He/cm2. However, when the ion fluence is 1×1019 D/cm2, the hydrogen saturation in vanadium alloy does not take place. Experimental results indicates that hydrogen and helium retention in vanadium alloy may lead to serious problems and special attention should be paid when it is applied to fusion reactors.

关键词： deuterium helium vanadium alloy thermal desorption spectroscopy retention and release

Spatial-controlled etching of coordination polymers

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Chinese Chemical Letters 2021年第2期32卷 635-641页

作者： Qi Dang Yucen Li Wei Zhang Yusuf Valentino Kaneti Ming Hu Yusuke yamauchi School of Physics and Electronic Science.East China Normal University Shanghai 200241China International Center for Materials Nanoarchitectonics(MANA) National Institute for Materials Science(NIMS)Ibaraki 305-0044Japan School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnology(A1BN) The University of QueenslandQueensland 4072Australia Department of Plant and Environmental New Resources Kyung Hee University.Gyeonggi-do 446-701South Korea

Nanoarchitectonics provide versatile opportunities for modifying the properties of coordination polymers(CP) other than molecular ***-controlled etching focuses on the controlled disassembly of the *** etching method provides an excellent opportunity for tailoring the properties and functions of the ***,we discuss the mechanism for controlled etching of the CPs and summarized the two main strategies utilized so *** examples are illustrated to demonstrate recent developments in this ***,advantages of the etched CPs are summarized in several important applications,including energy storage,catalysis and nanomedicine.

关键词： Coordination polymer Metal-organic frameworks Etching Hollow structure Sodium ion battery Catalysis Nanomedicine

Phyllanthus acidus(L.) Skeels and Rhinacanthus nasutus(L.) Kurz leaf extracts suppress melanogenesis in normal human epidermal melanocytes and reconstitutive skin culture

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Asian Pacific Journal of Tropical Medicine 2019年第3期12卷 98-105页

作者： Moragot Chatatikun Takeshi yamauchi Kenshi Yamasaki Anchalee Chiabchalard Setsuya Aiba Department of Medical Technology School of Allied Health Sciences Walailak University Department of Dermatology Tohoku University Graduate School of Medicine Deparment of Clinical Chemistry Faculty of Allied Health Sciences Chulalongkorn University

Objective: To determine the effect of extracts from Phyllanthus acidus(P. acidus)(L.) Skeels and Rhinacanthus nasutus(R. nasutus)(L.) Kurz leaves on melanogenesis and the underlying mechanism in normal human epidermal melanocytes(NHEM) and a reconstitutive skin model. Methods: NHEM and a reconstitutive skin model were stimulated with ethanol extracts of P. acidus(L.) Skeels and R. nasutus(L.) Kurz leaves. mRNA expression of microphthalmiaassociated transcription factor(MITF), tyrosinase(TYR), tyrosinase-related protein 1(TYRP1) and dopachrome tautomerase(DCT) were examined by real-time PCR. The melanin content in NHEM was also measured. Moreover, protein levels of tyrosinase were determined using western blot ***: In NHEM and the reconstitutive skin model, ethanol extracts from P. acidus(at 12.5 and 25.0 μg/mL) and R. nasutus(at 6.25 and 12.50 μg/mL) significantly diminished mRNA expression of MITF, TYR, TYRP1 and DCT in a concentration-dependent manner. P. acidus and R. nasutus extracts also reduced the amount of melanin in α-MSH-stimulated NHEM. Moreover, P. acidus and R. nasutus extracts markedly suppressed tyrosinase at the translational level in the reconstitutive skin model. Conclusions: P. acidus and R. nasutus extracts significantly reduced melanogenesis in NHEM and the reconstitutive skin model, suggesting that P. acidus and R. nasutus extracts can inhibit melanin synthesis through downregulation of MITF, TYR, TYRP1 and DCT. Therefore, the ethanol extracts of P. acidus and R. nasutus contain compounds that have the potential for development as a skin lightening agent for the treatment of hyperpigmentation disorder or melasma.

关键词： Phyllanthus acidus(L.) Skeels Rhinacanthus nasutus(L.) Kurz Melanin Tyrosinase MITF

Low temperature surface oxygen activation in crystalline MnO_(2) triggered by lattice confined Pd single atoms

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Journal of Energy Chemistry 2021年第11期30卷 136-144,I0003页

作者： Xuemei Liao Yonghui Zhao Changwen Liu Xiaopeng Li Yu Sund Kenichi Kato Miho yamauchi Zheng Jiang College of Food and Biological Engineering Xihua UniversityChengdu 610039SichuanChina CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute(SARI)Chinese Academy of Sciences(CAS)No.100Haike RoadPudong New DistrictShanghai 201210China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityNo.2999 North Renmin RoadSongjiang DistrictShanghai 201620China Institute for the Advancement of Higher Education Hokkaido UniversitySapporo 060-0817Japan Department of Chemistry Faculty of ScienceHokkaido UniversityN10W8Kita-kuSapporoHokkaido 060-0810Japan RIKEN SPring-8 Center1-1-1 KoutoSayo-choSayo-gunHyogo 679-5148Japan International Institute for Carbon-Neutral Energy Research(WPI-I2CNER) Kyushu UniversityMotooka 744Nishi-kuFukuoka 819-0395Japan Advanced Institute for Materials Research(AIMR) Tohoku University2-1-1 KatahiraAoba-kuSendai 980-8577Japan Shanghai Synchrotron Radiation Facility Zhangjiang LabShanghai Advanced Research Institute(SARI)Chinese Academy of Sciences(CAS)No.239 Zhangheng RoadPudong New DistrictShanghai 201203China Shanghai Institute of Applied Physics Chinese Academy of ScienceNo.2019 Jia Luo RoadJiading DistrictShanghai 201800China

Tuning the coordination environment is the research axis of single atom catalysts (SACs). SACs are commonly stabilized by various defects from support. Here, we report a lattice confined Pd SAC using MnO_(2) as support. Compared with the Pd clusters anchored on the surface, the lattice confined Pd single atoms allows spontaneous exaction of surrounding lattice oxygen at room temperature when employed in CO oxidation. The MnO_(2) supported Pd SAC exhibited a high turnover frequency of 0.203 s^(−1) at low reaction temperature, which is higher than that of recently reported Pd SACs. Theoretical calculations also confirmed the confined monatomic Pd activate lattice oxygen with an ultralow energy barrier. Our results illustrate that the unique coordination environment of single atom provided by lattice confinement is promising to boost the activity of SACs.

关键词： Single atom catalysts(SACs) Lattice confinement Oxygen activation Manganese oxide nanofiber

Concentrations of toxic heavy metals in ambient particulate matter in an industrial area of northeastern China

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Frontiers of Medicine 2008年第2期2卷 207-210页

作者： Fengyuan PIAO Xiance SUN Shuang LIU Toru yamauchi Department of Occupational and Environmental Health Dalian Medical UniversityDalian 116044China Department of Public Health School of MedicineMie UniversityTsu514–8507Japan

This paper investigates concentrations of vari-ous heavy metals in ambient particulate matter(PM)and provide evidence for prevention from air *** concentrations of heavy metal components in the PM were determined by inductively coupled plasma/Mass spectrometry(ICP/MS)from September 2000 to August 2002 in a northeast industrial city in ***-trations of Cd,Mn,Pb,Ni,Cr and As in the PM were 9.3,461.9,588.7,69.5,205.7 and 57.4 ng/m3 in the indus-trial area,and 5.7,245.5,305.0,31.4,58.8 and 32.5 ng/m3 in the main road,*** of these heavy metals except Cd were significantly higher in the industrial area and main road than those in the suburban area(P<0.05 or P<0.01).The change curves of the six heavy metal concentrations show their concentrations increased in the winter and spring,but decreased in the summer and *** results indicate that concentra-tions of the metals in the PM are relatively high in the industrial area and main road.

关键词： air pollution particulate matter heavy metals

Transcriptional regulation of human polo-like kinases and early mitotic inhibitors

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Journal of Genetics and Genomics 2008年第4期35卷 215-224页

作者： Moe Tategu Hiroki Nakagawa Kaori Sasaki Rieko yamauchi Sota Sekimachi Yuka Suita Naoko Watanabe Kenichi Yoshida Department of Life Sciences Meiji University School of Agriculture 1-1-1 Higashimita Tama-ku Kawasaki Kanagawa 214-8571 Japan

Human polo-like kinases （PLK1-PLK4） have been implicated in mitotic regulation and carcinogenesis. PLK1 phosphorylates early mitotic inhibitor 1 （Emil） to ensure mitosis entry, whereas Emi2 plays a key role during the meiotic cell cycle. Transcription factor E2F is primarily considered to regulate the G1/S transition of the cell cycle but its involvement in the regulation of mitosis has also been recently suggested. A gap still exists between the molecular basis of E2F and mitotic regulation. The present study was designed to characterize the transcriptional regulation of human PLK and Emi genes. Adenoviral overexpression of E2F1 increased PLK1 and PLK3 mRNA levels in A549 cells. A reporter gene assay revealed that the putative promoter regions of PLK1, PLK3, and PLK4 genes were responsive to activators E2F, E2F1-E2F3. We further characterized the putative promoter regions of Emil and Emi2 genes, and these could be regulated by activators E2F and E2F1-E2F4, respectively. Finally, PLK1-PLK4, Emil, and Emi2 mRNA expression levels in human adult, fetal tissues, and several cell lines indicated that each gene has a unique expression pattern but is uniquely expressed in common tissues and cells such as the testes and thymus. Collectively, these results indicate that E2F can integrate G1/S and G2/M to oscillate the cell cycle by regulating mitotic genes PLK and Emi, leading to determination of the cell fate.

关键词： polo-like kinase early mitotic inhibitor cell cycle E2F promoter gene regulation

Current status of endoscopic retrograde cholangiopancreatography in patients with surgically altered anatomy

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World Journal of Gastroenterology 2019年第26期25卷 3313-3333页

作者： Chonlada Krutsri Mitsuhiro Kida Hiroshi yamauchi Tomohisa Iwai Hiroshi Imaizumi Wasaburo Koizumi Department of Surgery Faculty of MedicineRamathibodi HospitalMahidol UniversityBangkok 10400Thailand Department of Gastroenterology Graduate School of MedicineKitasato University HospitalKanagawa 252-0375Japan

Endoscopic retrograde cholangiopancreatography(ERCP)in patients with surgically altered anatomy must be performed by a highly experienced *** challenges are accessing the afferent limb in different types of reconstruction,cannulating a papilla with a reverse orientation,and performing therapeutic interventions with uncommon endoscopic *** development of endoscopic techniques has led to higher success rates in this group of ***-assisted ERCP is the endoscopic procedure of choice for high success rates in short-limb reconstruction;however,these success rate is lower in long-limb *** assisted by endoscopic ultrasonography is now popular because it can be performed independent of the limb length;however,it must be performed by a highly experienced and skilled *** deployment and small stone removal can be performed immediately after ERCP assisted by endoscopic ultrasonography,but the second session is needed for other difficult procedures such as cholangioscopy-guided electrohydraulic ***-assisted ERCP has an almost 100%success rate in longlimb reconstruction because of the use of a conventional side-view duodenoscope,which is compatible with standard *** requires cooperation between the surgeon and endoscopist and is suitable in urgent situations requiring concomitant *** review focuses on the advantages,disadvantages,and outcomes of various procedures that are suitable in different situations and reconstruction *** new techniques and their outcomes are also discussed.

关键词： Endoscopic retrograde cholangiopancreatography Surgically altered anatomy Endoscopic retrograde cholangiopancreatography in Billroth II Endoscopic retrograde cholangiopancreatography post-Whipple Endoscopic ultrasonography-guided endoscopic retrograde cholangiopancreatography

Porous Metal Nanocrystal Catalysts:Can Crystalline Porosity Enable Catalytic Selectivity?

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CCS Chemistry 2022年第6期4卷 1829-1842页

作者： Xiaowen Min Hao Lv Yusuke yamauchi Ben Liu Key Laboratory of Green Chemistry and Technology of the Ministry of Education College of ChemistrySichuan UniversityChengdu 610064 Australian Institute for Bioengineering and Nanotechnology(AIBN) School of Chemical EngineeringThe University of QueenslandBrisbaneQLD 4072 JST-ERATO yamauchi Materials Space-Tectonics Project International Research Centre for Materials Nanoarchitechtonics(WPI-MANA)National Institute for Materials Science(NIMS)TsukubaIbaraki 305-0044

Catalytic selectivity is a central issue in the efficiency of catalytic processes.A large number of strategies have been developed to improve the catalytic selectivity of metal catalysts at the atomic and molecular levels,for instance,alloying secondary elements,fabricating metal-support interactions,and introducing surface ***,macro/mesoscopic pores and cavities have been demonstrated as an alternative route to promote catalytic selectivity of metal nanocrystal *** promotion effects of continuous crystalline porosity include(1)more catalytically active sites that accelerate the favorable catalytic routes to targeted products,(2)confined spaces that increase the retention time of key intermediates and remarkably promote the selective catalysis toward desired products,and(3)an optimized electronic structure and coordination environment of active metal sites that tailor the reaction trends of selective catalysis toward desired *** this minireview,we summarize recent advances in porosity-enabled catalytic selectivity of metal nanocrystal catalysts with focused discussions of CO_(2) reduction electrocatalysis and selective hydrogenation *** mechanisms that allow for the continuous porosity that enables the catalytic selectivity of metal nanocrystal catalysts are discussed in *** end this minireview by proposing current challenges and offering future opportunities in this research field.

关键词： porous metal continuous crystalline porosity structural synergy confinement catalytic selectivity