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Identification of sources of lead in the atmosphere by chemical speciation using X-ray absorption near-edge structure(XANES) spectroscopy

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Journal of Environmental Sciences 2014年第2期26卷 343-352页

作者： kohei Sakata Aya Sakaguchi Masaharu Tanimizu Yuichi Takaku Yuka Yokoyama Yoshio Takahashi Department of Earth and Planetary Systems Science Hiroshima University Kochi Institute for Core Sample Research Japan Agency for Marine-Earth Science and Technology Institute for Environmental Sciences

Sources of Pb pollution in the local atmosphere together with Pb species, major ions, and heavy metal concentrations in a size-fractionated aerosol sample from Higashi-Hiroshima （Japan） have been determined by X-ray absorption near-edge structure （XANES） spectroscopy, ion chromatography, and ICP-MS/AES, respectively. About 80% of total Pb was concentrated in fine aerosol particles. Lead species in the coarse aerosol particles were PbC204, 2PbCO3-Pb（OH）2, and Pb（NO3）2, whereas Pb species in the fine aerosol particles were PbC204, PbSO4, and Pb（NO3）2. Chemical speciation and abundance data suggested that the source of Pb in the fine aerosol particles was different from that of the coarse ones. The dominant sources of Pb in the fine aerosol particles were judged to be fly ash from a municipal solid waste incinerator and heavy oil combustion. For the coarse aerosol particles, road dust was considered to be the main Pb source. In addition to Pb species, elemental concentrations in the aerosols were also determined. The results suggested that Pb species in size-fractionated aerosols can be used to identify the origin of aerosol particles in the atmosphere as an alternative to Pb isotope ratio measurement.

关键词： lead lead speciation XAFS spectroscopy size-fractionated aerosol sample

Intracellular and extracellular TGF-β signaling in cancer： some recent topics

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Frontiers of Medicine 2018年第4期12卷 387-411页

作者： kohei Miyazono Yoko Katsuno Daizo Koinuma Shogo Ehata Masato Morikawa Department of Molecular Pathology Graduate School of Medicine The University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan

Transforming growth factor （TGF）-β regulates a wide variety of cellular responses, including cell growth arrest, apoptosis, cell differentiation, motility, invasion, extracellular matrix production, tissue fibrosis, angiogenesis, and immune function. Although tumor-suppressive roles of TGF-β have been extensively studied and well-characterized in many cancers, especially at early stages, accumulating evidence has revealed the critical roles of TGF-β as a pro-tumorigenic factor in various types of cancer. This review will focus on recent findings regarding epithelial-mesenchymal transition （EMT） induced by TGF-β, in relation to crosstalk with some other signaling pathways, and the roles of TGF-[~ in lung and pancreatic cancers, in which TGF-β has been shown to be involved in cancer progression. Recent findings also strongly suggested that targeting TGF-β signaling using specific inhibitors may be useful for the treatment of some cancers. TGF-β plays a pivotal role in the differentiation and function of regulatory T cells （Tregs）. TGF-β is produced as latent high molecular weight complexes, and the latent TGF-β complex expressed on the surface of Tregs contains glycoprotein A repetitions predominant （GARP, also known as leucine-rich repeat containing 32 or LRRC32）. Inhibition of the TGF-β activities through regulation of the latent TGF-β complex activation will be discussed.

关键词： TGF-β EMT lung cancer pancreatic cancer latent form immune function GARP

Feasibility of drug delivery to the eye’s posterior segment by topical instillation of PLGA nanoparticles

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Asian Journal of Pharmaceutical Sciences 2017年第4期12卷 394-399页

作者： kohei Tahara Keiichi Karasawa Risako Onodera Hirofumi Takeuchi Laboratory of Pharmaceutical Engineering Gifu Pharmaceutical University

We investigated the delivery of drugs to the posterior segment of the eye by non-invasive topical instillation using submicron-sized poly(D,L-lactide-co-glycolide)(PLGA) nanoparticles(NPs). Surface-modified PLGA NPs were developed to improve the drug delivery efficiency to the retina and were administered as topical eye drops to mice. Chitosan(CS) and glycol chitosan(GCS), which are mucoadhesive polymers, and polysorbate 80(P80) were used as surface modifiers, and have been reported to increase the association of NPs with ***-6 was used as a model drug and fluorescent marker, and after ocular administration of PLGA NP eye drops, the fluorescence intensity of coumarin-6 was observed in the retina. The fluorescence image analysis indicated that there are several possible routes to the retina and fates of PLGA NPs in ocular tissue, and that these pathways involved the corneal,non-corneal, or uveal routes. Delivery to the mouse retina segments after topical administration was increased by surface modification with CS, GCS, or P80. Surface-modified PLGA NPs are a promising method for retinal drug delivery via topical instillation.

关键词： PLGA Nanoparticles Topical instillation Retina Surface modification

Study of hadrons using the Gaussian functional method in the O(4) linear σ model

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Chinese Physics C 2015年第6期39卷 52-63页

作者：陈华星 Shotaro imai Hiroshi Toki 耿立升 School of Physics and Nuclear Energy Engineering and International Research Center for Nuclei and Particles in the Cosmos Beihang University Department of Physics Kyoto University Meme Media Laboratory Hokkaido University Research Center for Nuclear Physics Osaka University

We study properties of hadrons in the O（4） linear σ model, where we take into account fluctuations of mesons around their mean field values using the Gaussian functional （GF） method. In the GF method we calculate dressed σ and π masses, where we include the effect of fluctuations of mesons to find a better ground state wave function than the mean field approximation. Then we solve the Bethe-Salpeter equations and calculate physical σ and π masses. We recover the Nambu-Goldstone theorem for the physical pion mass to be zero in the chiral limit. The σ meson is a strongly correlated meson-meson state, and seems to have a two meson composite structure. We calculate σ and π masses as functions of temperature for both the chiral limit and explicit chiral symmetry breaking case. We get similar behaviors for the physical σ and π masses as the case of the mean field approximation, but the coupling constants are much larger than the values of the case of the mean field approximation.

关键词： linear a model sigma and pion Gaussian functional method Bethe-Salpeter equation Nambu Goldstone theorem finite temperature

Effects of ethanol and sex on propionate metabolism evaluated via a faster ^(13)C-propionate breath test in rats

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World Journal of Gastroenterology 2023年第21期29卷 3269-3279页

作者： Yosuke Sasaki Naoyuki Kawagoe Tsunehiko imai Yoshihisa Urita Department of General Medicine and Emergency Care Toho University School of MedicineTokyo 143-8541Japan

BACKGROUND Alcoholism is regarded as a risk factor for vitamin B_(12)(VB_(12))*** V B_(12) serves as a coenzyme of methylmalonyl-CoA mutase,a key enzyme in propionate metabolism,the ^(13)C-propionate breath test(PBT)has been studied as a non-invasive diagnostic modality for VB_(12) ***,the conventional PBT requires 2 h,which is inconvenient in clinical *** hypothesized that a faster PBT can be used to evaluate propionate metabolism and is more easily adaptable for clinical *** To evaluate a faster PBT for assessing the effects of long-term ethanol consumption on propionate metabolism in ethanol-fed rats(ERs).METHODS ERs were obtained by replacing standard drinking water(for control rats,CRs)with 16%ethanol solution in descendants of F344/DuCrj *** PBT was performed by administering ^(13)C-propionate aqueous solution to male and female ERs and CRs by inserting a metal tubule from the mouth to the stomach;exhaled gas was collected in a bag to measure its ^(13)CO_(2)/12CO_(2) isotope ratio via infrared isotope *** VB_(12) and alanine transaminase(ALT)levels were measured via chemiluminescence immunoassay and the lactate dehydrogenaseultraviolet method,*** evaluated statistical differences in mean body weight,change in ^(13)CO_(2)(Δ^(13)CO_(2)‰),peakΔ^(13)CO_(2)‰,and serum VB_(12) and ALT,between males and females and between ERs and CRs using the t-test and Mann-Whitney U test for normally and non-normally distributed variables,*** Males weighed significantly more than females(P<0.001);CRs weighed significantly more than ERs(P<0.008).Δ^(13)CO_(2) reached a peak(C_(max))at 20 min and 30 min in females and males,respectively,decreasing after 20-30 min without rebound in all *** had significantly higher C_(max) andΔ^(13)CO_(2) at 15-45 min than females(P<0.05;for all pairs).Propionate metabolism was enhanced in male ERs relative to male CRs,whereas metabolism did no

关键词： Alcoholism Breath test Carbon isotope Gut flora Propionate Vitamin B12

Arterial-phase contrast-enhanced ultrasonography for evaluating anti-angiogenesis treatment: A pilot study

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World Journal of Gastroenterology 2011年第8期17卷 1045-1050页

作者： Keiko Yoshida Tomihiko Hirokawa Fuminori Moriyasu Masahiko Yamada Yasuharu imai Department of Gastroenterology and Hepatology Tokyo Medical University

AIM:To verify whether arterial-phase contrast-enhanced ultrasonography(CEUS) of tumor parenchymal tissue is useful for evaluation of anti-angiogenesis ***:Rabbits with liver tumor were subjected to CEUS,and images of the nodular maximal diameter in vascular phase were *** analysis was performed to plot the time intensity curve(TIC) at the tumor parenchyma,which set the diameter of the region of interest of intensity *** TIC was calculated to obtain the time to peak intensity(TPI) and the magnitude of *** were randomly assigned to a treatment group with sorafenib and a control *** weeks later,the same ultrasound examination was repeated followed by pathological testing to assess the effect of sorafenib on the liver ***:In four rabbits in the treatment group,the rate of change of tumor size was decreased comparedwith that of the control(the rate 2.3 vs 7.9,P = 0.02).The TPI of the treatment group elongated significantly(the rate 3.1 vs 1.1,P = 0.07 for SonoVue,2.0 vs 0.88,P = 0.09 for Sonazoid).The magnitude of PI showed no significant *** pathological examination,capillary diameters in the treatment group were significantly smaller than those in the control group(26.4 vs 42.8 μm,P = 0.013).CONCLUSION:Analysis of the TIC in the arterial phase of tumor tissue could evaluate the efficacy of antiangiogenesis drug treatment in liver tumor.

关键词： Liver tumor Ultrasound agent Contrast-enhanced ultrasonography Sorafenib Animal model

Long-term health-related quality of life of living liver donors:what should the transplant team know?

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Hepatobiliary Surgery and Nutrition 2021年第3期10卷 394-396页

作者： kohei Ogawa Katsunori Sakamoto Yasutsugu Takada Department of Hepatobiliary Pancreatic and Breast Surgery Ehime UniversityShitsukawaToonEhimeJapan

Living-donor liver transplantation(LDLT)has been established as an alternative to deceased donor liver transplantation as a treatment option for patients with end-stage liver *** in Japan,where the number of deceased donor liver transplants is extremely small compared to Western countries,LDLT still accounts for the majority of liver transplants.

关键词： liver donor patients

Experimental Study on a Single Layer Two-Way Grid Shell with Tension Members

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Journal of Harbin Institute of Technology(New Series) 2015年第4期22卷 10-19页

作者： Zhonghao Zhang Masumi Fujimoto Atsuo Takino Katsuhiko imai School of Civil Engineering Harbin Institute of Technology School of Water Conservancy and Civil Engineering Northeast Agricultural University Osaka City University Nara Women's University Forest Engineering & Economics Lab.Ikeda

Single layer two-way grid shell with in-plane and out-of-plane tension members is a new type of single-layer latticed shell roofs. Compared with traditional single-layer latticed shells,this new type has a unique mesh form and excellent rigidity. In order to further understand the buckling behaviors of single layer two-way grid cylindrical shell roof with tension members,the buckling experiments have been undertaken to investigate the effect of tension members,in either out-of-plane or in-plane placement. A single layer two-way grid cylindrical shell roof with out-of-plane tension members has been tested under symmetric and asymmetric loading. The tension member placement,the introducing initial axial force to tension members and the load patterns are considered to investigate the buckling behavior. Experimental results indicate that four long out-ofplane tension members work well under symmetrical loading,but only two long out-of-plane tension members work under asymmetrical loading. It can be concluded that the PC bar members used as tension members for this study are useful in the construction of a single layer two-way grid cylindrical shell roof with structural members intersecting at small angles.

关键词： single layer two-way grid shell tension members out-of-plane placement buckling behavior truss system

Characterization of termetallic Pt-Ir-Au catalysts for NO decomposition

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Rare Metals 2011年第1期30卷 53-57页

作者： Akira Morikawa kohei Okumura Masaru Ishii Koichi Kikuta Akihiko Suda Hirofumi Shinjo Catalyst Lab. Toyota Central R&D Labs.Inc.41-1 YokomichiNagakuteNagakute-ChoAichi-GunAichi 480-1192Japan Vehicle Engineering Group Material Engineering Division ⅡToyota Motor Corporation1 Toyota-choToyotaAichi 471-8572Japan Department of Crystalline Materials Science School of EngineeringNagoya UniversityFuro-ChoChikusa-KuNagoyaAichi 464-8603Japan

A termetallic catalyst of Pt-Ir-Au/Al2O3 for NOx decomposition was prepared by loading the metallic colloids in C2H5OH-H2O solution and a surfactant of polyvinyl *** with an impregnated Pt/Al2O3 catalyst,the termetallic catalyst of PtIrAu811/Al2O3,with a Pt：Ir：Au atomic ratio of 8：1：1,exhibited higher NO decomposition and selectivity to *** electron microscopy and X-ray diffraction were conducted to clarify the state of the supported metals and indicate three precious metals alloyed on the *** the study of NO-temperature programmed desorption,oxygen desorption on the PtIrAu811 catalyst shifted to the low temperature side compared to that on Pt/Al2O3,which correlated well with its higher catalytic performance in NO decomposition.

关键词： catalysts iridium gold platinum decomposition nitrogen oxides