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Effects of Hydrogen-bonding Interaction and Polarity on Emission Spectrum of Naphthalene-Triethylamine in Mixed Solvent

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Chemical Research in Chinese Universities 2004年第5期20卷 606-611页

作者： Yoshimi sueishi Shunzo Yamamoto Graduate School of Natural Science and Technology Okayama University 3-1-1 Tsushima-Naka Okayama 700-8530 JapanGraduate School of Natural Science and Technology Okayama University 3-1-1 Tsushima-Naka Okayama 700-8530 Japan

The effects of the protic and aprotic polar solvents on the emission spectrum of the naphthalene-triethyl-amine system in THF were studied under conditions of steady-state illumination. The fluorescence spectrum of the naphthalene-triethylamine system consists of two emission bands, the fluorescence band of naphthalene(band A, 329 nm) and the emission band of the exciplex(band B, 468 nm). The intensities of both the emission bands decrease with increasing the solvent polarity. The intensity of band B also decreases due to the hydrogen-bonding interaction between triethylamine and protic solvent, while that of band A increases. It is thus suggested that the quenching of naphthalene fluorescence by triethylamine in THF occurs through the charge transfer and electron transfer reactions. The spectral changes upon the increase of solvent polarity can be explained by the dependences of the equilibrium constant between exciplex and ion-pair and the rate constant for the electron transfer reaction from triethylamine to the excited naphthalene on the relative permittivity of solvent. It is shown that the formation of intermolecular hydrogen-bonding between triethylamine and protic solvent suppresses the quenching reaction by the decrease in free amine. Acetonitrile has only a polar effect and trichloroacetic acid only a hydrogen-bonding(or protonation) effect, while alcohols have both the effects. The effects of alcohols could be separated into the effects of solvent polarity and intermolecular hydrogen-bonding interaction quantitatively.

关键词： Naphthalene-triethylamine Fluorescence spectrum Solvent effect Solvent polarity Hydrogen-bonding interaction.

Effects of Pressure, Solvent, and Substituent on the Thermal Isomerization of 2-Oxo- spiro[diazirine-3,3'-indoline]

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Chemical Research in Chinese Universities 2001年第1期17卷 95-101页

作者： Yoshimi sueishi Genta Okazaki Department of Chemistry Faculty of ScienceOkayama UniversityTsushima Naka 3-1-1Okayama 700-8530Japan

The kinetic effects of pressure, solvent, and substituent on the thermal isomerization from 2 oxospiro[diazirine 3,3 indoline] to 3 diazo 2 oxo indoline have been examined. The rate constants of the thermal isomerization increased with increasing external pressure and were related to the σ + P substituent constant of Hammett correlation. The results suggest that the thermal isomerization proceeds via a dipolar transition state involving heterolytic bond fission. However, the kinetic solvent effects on the thermal isomerization were not observed. The special solvent effects were discussed on the basis of the linear free energy relationship.

关键词： kinetic study Pressure effect Substituent effect Thermal isomerization Diazirine

kinetic Studies of Solvent and Pressure Effects on the Thermal Isomerization of Palladium Dithizonate

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Chemical Research in Chinese Universities 2000年第2期16卷 141-145页

作者： Yoshimi sueishi kazumi Matsumoto Okayama Univ Fac Sci Dept Chem Okayama 7008530 Japan

The isomerization of mercury bisdithizonate having tetrahedral stereochemistry occurs in each ligand independently and is unaffected by the presence of the second ligand attached to the same central metal. The effects of solvent and pressure on the thermal isomerization of the square-planar Pd dithizonate complex were studied to determine the influence of ligand on the isomerization rate. The results were compared to those obtained with Hg(HDz)2. The mechanistic implications for the thermal isomerization of Pd(HDz)2 were presented.

关键词： Metal dithizonate kinetic study Solvent effect Pressure effect

An EPR Study on Intramolecular Spin Exchange and Rotational Mobility of Nitroxides Linked by a Long-chain

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Chemical Research in Chinese Universities 1999年第2期15卷 82-89页

作者： Yoshimi sueishi katsumi Noritake LIU Yingjin Department of Chemistry Faculty of ScienceOkayama UniversityTsushima Naka 311Okayama 7008530Japan

The effects of pressure and solvent on the intramolecular spin exchange of biradicals having two nitroxide fragments linked by a long flexible chain were studied by means of highpressure EPR *** was found that the intramolecular exchange interaction between nitroxides of biradical took place through the direct contact between *** analyzing the observed EPR spectra,we have estimated the ratio(in/out)value of the average lifetime of the radical fragments inside a cage(in)to that outside the cage(out).The in/out values decreased with decreasing temperature and increasing *** results suggest that the nearly cyclic conformation in a cage is favorable in ***,the rotational correlation time of individual nitroxide was estimated from the anisotropic EPR signal,and the information on the segmental motion of the nitroxide group in biradical was obtained.

关键词： EPR Spin exchange Pressure effect Rotational correlation time exchange, Pressure effect, Rotational correlation time

LESSONS IN PREVENTION OF ISCHEMIC HEART DISEASE LEARNED FROM PATHOLOGICAL STUDIES OF CORONARY ATHEROSCLEROSIS

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中华医学杂志(英文版) 1992年第5期105卷 390-393页

作者： kenzo Tanaka katsuo sueishi Department of Pathology Faculty of Medicine Kyushu University Japan

The recent status of the extent and severity ofatherosclerosis in Japanese children and young adultsand its causative factor are *** materialand data are collected from 2 856 autopsies,with theage range of 1 month to 39 ***-fibrinmetabolism in the arterial wall has a definite role *** incidence of myocardial infarctionin 539 consecutive autopsy cases over 40 years old atkyushu University is 12.7%.

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Spin Trapping of the Phosphorus-centered Radicals Generated from Hydrogen Abstraction Reaction by 2,2-Diphenyl-1-picrylhydrazyl

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Chemical Research in Chinese Universities 2000年第4期16卷 313-319页

作者： Yoshimi sueishi and Yuko Nishihara (Department of Chemistry, Faculty of Science, Okayama University, 3-1-1 Tsushima Naka, Okayama 700-8530, Japan) Okayama Univ Fac Sci Dept Chem Okayama 7008530 Japan

Two kinds of the phosphorus-centered radicals produced from hydrogen atomion by 2, 2-diphenyl-1-picrylhydrazyl(DPPH were trapped by N-tert-butyl-α-phenylnitrone(PBN) and 5, 5-dimethyl-1-pyrroline N-oxide (DMPO), and investigated by means of EPR spectroscopy. The spin adducts with a characteristic hyperfine coupling constant(hfcc) caused by a phosphorus atom were observed. Based on the hfcc values caused by the phosphorus and hydrogen atoms, the con formational positions of the adducts trapped by PBN and DMPO are discussed.

关键词： EPR Spin trap Phosphorus-centered radical

Reduced hemoglobin and increased C-reactive protein are associated with upper gastrointestinal bleeding

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World Journal of Gastroenterology 2014年第5期20卷 1311-1317页

作者： Minoru Tomizawa Fuminobu Shinozaki Rumiko Hasegawa Akira Togawa Yoshinori Shirai Noboru Ichiki Yasufumi Motoyoshi Takao Sugiyama Shigenori Yamamoto Makoto sueishi Department of Gastroenterology National Hospital Organization Shimoshizu Hospital Yotsukaido City Department of Radiology National Hospital Organization Shimoshizu Hospital Yotsukaido City Department of Surgery National Hospital Organization Shimoshizu Hospital Yotsukaido City Department of Neurology National Hos- pital Organization Shimoshizu Hospital Yotsukaido City Department of Rheumatology National Hospital Organization Shimoshizu Hospital Yotsukaido City Department of Pediatrics National Hospital Organization Shimoshizu Hospital Yotsukaido City

AIM: To investigate the early upper gastrointestinal endoscopy (endoscopy) significantly reduces mortality resulting from upper gastrointestinal (GI) bleeding.

关键词： Receiver operating characteristic Area under curve Sensitivity Specificity Gastrointestinal bleeding

Insulin-like growth factor-I receptor in proliferation and motility of pancreatic cancer

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World Journal of Gastroenterology 2010年第15期16卷 1854-1858页

作者： Minoru Tomizawa Fuminobu Shinozaki Takao Sugiyama Shigenori Yamamoto Makoto sueishi Takanobu Yoshida Department of Gastroenterology National Hospital Organization Shimoshizu Hospital Department of Radiology National Hospital Organization Shimoshizu Hospital Department of Rheu-matology National Hospital Organization Shimoshizu Hospital Department of Pediatrics National Hospital Organization Shimoshizu Hospital Department of Internal Medicine National Hospital Organization Shimoshizu Hospital

AIM:To develop a molecular therapy for pancreatic cancer, the insulin-like growth factor-I (IGF-I) signaling pathway was ***: Pancreatic cancer cell lines (MIA-Paca2, NOR-P1, PANC-1, Pk-45H, Pk-1, Pk-59 and kP-4) were cultured in media with 10 mL/L fetal bovine serum. Western blotting analysis was performed to clarify the expression of IGF-I receptor (IGF-IR). Picropodophyllin (PPP), a specific inhibitor of IGF-IR, LY294002, a specific inhibitor of phosphatidylinositol3 kinase (PI3k), and PD98059, a specific inhibitor of mitogen-activated protein kinase, were added to the media. After 72 h, a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay was performed to analyze cell proliferation. A wound assay was performed to analyze cell motility with hematoxylin and eosin (HE) staining 48 h after addition of each inhibitor. RESULTS: All cell lines clearly expressed not only IGF-IR but also phosphorylated IGF-IR. PPP significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, Pk-45H, Pk-1, Pk-59 and kP-4 cells to 36.9% ± 2.4% (mean ± SD), 30.9% ± 5.5%, 23.8% ± 3.9%, 37.1% ± 5.3%, 10.4% ± 4.5%, 52.5% ± 4.5% and 22.6% ± 0.4%, at 2 μmol/L, respectively (P k-45H, Pk-1, Pk-59 and kP-4 cells to 44.4% ± 7.6%, 32.9% ± 8.2%, 53.9% ± 8.0%, 52.8% ± 4.0%, 32.3% ± 4.2%, 51.8% ± 4.5%, and 30.6% ± 9.4%, at 50 μmol/L, respectively (P k-45H, Pk-1, Pk-59 and kP-4 cells to 3.0% ± 0.2%, 0%, 0%, 2.0% ± 0.1%, 5.0% ± 0.2%, 3.0% ± 0.1%, and 5.0% ± 0.2%, respectively (P k-45H, Pk-1, Pk-59 and kP-4 to 3.0% ± 0.2%, 0%, 3.0% ± 0.2%, 0%, 0%, 0% and 3% ± 0.1%, respectively (P < 0.05). PD980509 at 20 μmol/L did not suppress

关键词： Insulin-like growth factor-I receptor Phosphatidylinositol 3 kinase Pancreatic neoplasms

Sonoporation:Gene transfer using ultrasound

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World Journal of Methodology 2013年第4期3卷 39-44页

作者： Minoru Tomizawa Fuminobu Shinozaki Yasufumi Motoyoshi Takao Sugiyama Shigenori Yamamoto Makoto sueishi Department of Gastroenterology National Hospital Organization Shimoshizu HospitalYotsukaido CityChiba 284-0003Japan Department of Radiology National Hospital Organization Shimoshizu HospitalYotsukaido CityChiba 284-0003Japan Department of Neurology National Hospital Organization Shimoshizu HospitalYotsukaido CityChiba 284-0003Japan Department of Rheumatology National Hospital Organization Shimoshizu HospitalYotsukaido CityChiba 284-0003Japan Department of Pediatrics National Hospital Organization Shimoshizu Hospital934-5 ShikawatashiYotsukaido CityChiba 284-0003Japan

Genes can be transferred using viral or non-viral ***-viral methods that use plasmid DNA and short interference RNA(si RNA)have advantages,such as low immunogenicity and low likelihood of genomic integration in the host,when compared to viral ***-viral methods have potential merit,but their gene transfer efficiency is not ***,new methods should be ***-frequency ultrasound irradiation causes mechanical perturbation of the cell membrane,allowing the uptake of large molecules in the vicinity of the cavitation *** collapse of these bubbles generates small transient holes in the cell membrane and induces transient membrane *** formation of small pores in the cell membrane using ultrasound allows the transfer of DNA/RNA into the *** phenomenon is known as sonoporation and is a gene delivery method that shows great promise as a potential new approach in gene *** lower the threshold of cavity *** of therapeutic genes and microbubbles improve the transfer efficiency of *** ultrasound is potentially a suitable sonoporator because it allows the real-time monitoring of irradiated fields.

关键词： Gene therapy Cavity Microbubbles Con-trast agent Diagnostic ultrasound