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Meso-substituted cationic 3-and 4-N-Pyridylporphyrins and their Zn(II)derivatives for antibacterial photodynamic therapy

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Journal of Innovative Optical Health Sciences 2022年第1期15卷 1-16页

作者： Aram G.gyulkhandanyan Marina H.Paronyan Anna G.gyulkhandanyan Karapet R.Ghazaryan Marina v.Parkhats Boris M.Dzhagarov Maria v.Korchenova Ekaterina N.Lazareva Elena S.Tuchina grigor v.gyulkhandanyan valery v.Tuchin H.Buniatyan Institute of Biochemistry National Academy of Sciences of Armenia 5/1 Paruir Sevak Street Yerevan 0014Armenia INSERM U1204 Universite d'Evry vald'Essonne-Universite Paris-Saclay 1 Ruedu Pere JarlanBatiment Maupertuis91025Evry-CourcouronnesFrance B.I.Stepanov Institute of Physics National Academy of Sciences of Belarus 68-2 Nezavisimosti AvenueMinsk 220072Belarus Science Medical Center Saratov State University 83 Astrakhanskaya StreetSaratov 410012Russia Laboratory of Laser Molecular Imaging and Machine Learning(LMIML)National Research Tomsk State University 36 Lenin Avenue Tomsk 634050Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precision Mechanics and Control Russian Academy of Sciences Saratov 410028Russia

Photodynamic inactivation of microorganisms known as antibacterial photodynamic therapy(APDT)is one of the most promising and innovative approaches for the destruction of pathogenic *** the photosensitizers(PSs),compounds based on cationic porphyrins/metalloporphyrins are most successfully used to inactivate *** of meso-substituted cationic pyridylporphyrins and metalloporphyrins with various peripheral groups in the third and fourth positions of the pyrrole ring have been synthesized in *** aim of this work was to determine and test the most e®ective cationic porphyrins and metalloporphyrins with high photoactivity against Gram negative and Gram positive *** was shown that the synthesized cationic pyridylporphyrins/metalloporphyrins exhibit a high degree of phototoxicity towards both types of bacteria,including the methicillinresistant *** *** complexes of porphyrins are more phototoxic than metal-free porphyrin *** e®ectiveness of these Zn–metalloporphyrins on bacteria is consistent with the level of singlet oxygen *** was found that the high antibacterial activity of the studied cationic porphyrins/metalloporphyrins depends on four factors:the presence in the porphyrin macrocycle of a positive charge(+4),a central metal atom(Zn2þÞand hydrophobic peripheral functional groups as well as high values of quantum yields of singlet *** results indicate that meso-substituted cationic pyridylporphyrins/metalloporphyrins cannd wider application in photoinactivation of bacteria than anionic or neutral PSs usually used in APDT.

关键词： Antibacterial photodynamic therapy cationic porphyrins/metalloporphyrins phototoxicity Zn-metalloporphyrins singlet oxygen quantum yield Gram negative and Gram positive bacteria S.aureus MRSA E.coli Salmonella typhimurium.

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The role of singlet oxygen and hydroxyl radical in the photobleaching of meso-substituted cationic pyridyl porphyrins in the presence of folic acid

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 67-80页

作者： Lusine Mkrtchyan Torgom Seferyan Marina Parkhats Sergei Lepeshkevich Boris Dzhagarov Gagik Shmavonyan Elena Tuchina valery Tuchin grigor gyulkhandanyan Laboratory of Bioengineering Institute of Biochemistry After H.Buniatyan of the NAS of Armenia 5/1 Paruyr Sevak StreetYerevan 0014Armenia Laboratory of Biomedical Research Institute of Biochemistry after H.Buniatyan of the NAS of Armenia 5/1 Paruyr Sevak StreetYerevan 0014Armenia B.I.Stepanov Institute of Physics NAS of Belarus 68-2 Nezavisimosti Avenue Minsk 220072Belarus National Polytechnic University of Armenia 105 Teryan Street Yerevan 0009Armenia Science Medical Centre Saratov State University 83 Astrakhanskaya StreetSaratov 410012Russia

Using a photosensitizer(PS),light,and oxygen,photodynamic therapy creates cytotoxic reactive oxygen species,such as singlet oxygen(1O2),that kill cancer *** cancer cell lines have up to 300 times more folic acid receptors than healthy ***,folic acid is often used to improve selectivity of *** poses a disadvantage for *** this paper,we have studied the photoinduced changes of meso-substituted cationic pyridyl porphyrins in the presence of folic acid using uorescence and absorption *** this work,it was demonstrated that L-histidine,which is a 1O2 quencher,and D-mannitol,which is a hydroxyl radical quencher,can reduce photobleaching of cationic porphyrins and their interaction products with *** implies both singlet oxygen and hydroxyl radicals are involved in ***,our study revealed certain important features of the photobleaching of cationic porphyrins in the presence of folic acid.

关键词： Photodynamic therapy cancer quenchers histidine mannitol

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Existence of positive solutions to some nonlinear equations on locally finite graphs

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Science China Mathematics 2017年第7期60卷 1311-1324页

作者： grigor''YAN Alexander LIN Yong YANG YunYan Department of Mathematics University of BielefeldBielefeld 33501Germany School of Mathematical Sciences and Laboratory of Pure Mathematics and Combinatorics Nankai UniversityTianjin 300071China Department of Mathematics Renmin University of ChinaBeijing 100872China

Let G =(v,E) be a locally finite graph,whose measure μ(x) has positive lower bound,and A be the usual graph *** the mountain-pass theorem due to Ambrosetti and Rabinowitz(1973),we establish existence results for some nonlinear equations,namely △u+hu=f(x,u),x∈*** particular,we prove that if h and f satisfy certain assumptions,then the above-mentioned equation has strictly positive ***,we consider existence of positive solutions of the perturbed equation △u+hu=f(x,u)+∈*** problems have been extensively studied on the Euclidean space as well as on Riemannian manifolds.

关键词： variational method mountain-pass theorem semi-linear equation on graphs

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沸石催化剂上降冰片烯二聚（英文）

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催化学报 2015年第3期36卷 268-273页

作者： N.G.grigor'eva S.v.Bubennov L.M.Khalilov B.I.Kutepov Federal State Budget Institution of Science Institute of Petrochemistry and CatalysisRussian Academy of Sciences141 prosp.Oktyabrya450075 UfaRussian Federation

The high activity and selectivity of H‐Beta and H‐ZSM‐12 zeolites in the dimerization of norbornene was *** norbornene conversion reached 100% in chlorinated paraffin and argon gas medium,with a selectivity of dimer formation of 88%–98%.Four stereo‐isomers of the bis‐2,2'‐norbornylidene structure were identified in the dimer fraction,with the(Z)‐anti‐bis‐2,2'‐norbornylidene prevailing over the others.

关键词：降冰片烯沸石催化剂二聚体 Beta版氯化石蜡高活性 ZSM 转化率

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Leakage-Penumbra effect in intensity modulated radiation therapy step-and-shoot dose delivery

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World Journal of Radiology 2016年第1期8卷 73-81页

作者： grigor N grigorov James CL Chow Medical Physics Department Grand River Regional Cancer Center Radiation Medicine Program Princess Margaret Cancer Center Department of Radiation Oncology University of Toronto

AIM: To study the leakage-penumbra(LP) effect with a proposed correction method for the step-and-shoot intensity modulated radiation therapy(IMRT).METHODS: Leakage-penumbra dose profiles from 10 randomly selected prostate IMRT plans were studied. The IMRT plans were delivered by a varian 21 EX linear accelerator equipped with a 120-leaf multileaf collimator(MLC). For each treatment plan created by the Pinnacle3 treatment planning system,a 3-dimensional LP dose distribution generated by 5 coplanar photon beams,starting from 0o with equal separation of 72 o,was investigated. For each photon beam used in the stepand-shoot IMRT plans,the first beam segment was set to have the largest area in the MLC leaf-sequencing,and was equal to the planning target volume(PTv). The overshoot effect(OSE) and the segment positional errors were measured using a solid water phantom with Kodak(TL and X-OMAT v) radiographic films. Film dosimetric analysis and calibration were carried out using a film scanner(vidar vXR-16). The LP dose profiles were determined by eliminating the OSE and segment positional errors with specific individual irradiations. RESULTS: A non-uniformly distributed leaf LP dose ranging from 3% to 5% of the beam dose was measured in clinical IMRT beams. An overdose at the gap between neighboring segments,represented as dose peaks of up to 10% of the total BP,was measured. The LP effect increased the dose to the PTv and surrounding critical tissues. In addition,the effectdepends on the number of beams and segments for each beam. Segment positional error was less than the maximum tolerance of 1 mm under a dose rate of 600 monitor units per minute in the treatment plans. The OSE varying with the dose rate was observed in all photon beams,and the effect increased from 1 to 1.3 Gy per treatment of the rectal intersection. As the dosimetric impacts from the LP effect and OSE may increase the rectal post-radiation effects,a correction of LP was proposed and demonstrated for th

关键词： Multileaf collimator leakage Overshoot effect Beam penumbra Prostate intensity modulated radiation therapy planning

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Magnetometry and Hyperthermia Study of Magnetic Fluid Preparation UNIMAG

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World Journal of Condensed Matter Physics 2014年第1期4卷 6-12页

作者： grigor I. Mamniashvili Solomon v. Mikeladze Тatiana О. Gegechkori Besiki v. Surguladze Giorgi N. Pichkhaia Anatoli M. Akhalkatsi Dimitri M. Daraselia Davit L. Japaridze Andronikashvili Institute of Physics Ivane Javakhishvili Tbilisi State University Tbilisi Georgia ATT Ltd. Scientific Laboratory “Magnetic Fluids in Medicine and Biology” Tbilisi Georgia Ivane Javakhishvili Tbilisi State University Tbilisi Georgia Natishvili Institute of Morphology Ivane Javakhishvili Tbilisi State University Tbilisi Georgia

We investigated the hyperthermal and magnetic properties of the stable magnetic suspension of magnetite nanoparticles. With this purpose in mind, we designed a low-frequency oscillator, 300 W, 300 KHz. A sample of the magnetic suspension was placed in the induction coil and heated up to 55°C for 30 minutes. Based on the results of measurements of transverse susceptibility, we can infer that the suspension was superparamagnetic at room temperature and transformed into the magnetic state at nitrogen temperature. Comparing the obtained experimental results with the literature data, we assessed the mean size of nanoparticles, which made up about 10 nm. Computer simulation assessment on the basis of magnetization curve gives close results.

关键词： Magnetic Nanoparticles Suspension Hyperthermia Magnetometry NMR

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Long-Term H2O and CO2 Trends in Conifer Disc Tree Rings and Meteorological Parameters

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Journal of Life Sciences 2013年第9期7卷 1002-1008页

作者： Ageev Boris grigor'evich Gruzdev Aleksandr Nikolaevich Bondarenko Svetlana Leonidovna Sapozhnikova valeria Aleksandrovna v.E. Zuev Institute of Atmospheric Optics SB RAS Tomsk 634021 Russia MA.Obukhov Institute of Atmospheric Physics RAS Moscow 119017 Russia Institute for Monitoring of Climatic and Ecological Systems SB RAS Tomsk 634055 Russia

Results of investigations into the CO2 content in tree disc rings by the method proposed here have shown that a considerable part of CO2 generated under cell respiration is found in tree stems. Besides, annual CO2 distribution in tree rings exhibits a well-defined cyclicity. Results obtained from investigations into long-term CO2 and H2O variations in tree discs performed by different methods are presented. Wavelet and spectral analyses of the relationship between CO2 and H2O variations in a Siberian stone pine disc and meteorological parameters were made. The CO2 annual distributions of seven spruce tree discs were examined by the Caterpiller-SSA method. Wood samples of Siberian stone pine and spruce trees were taken from the same site in Tomsk region （Siberia, Russia） that characterized by an optimum growth habitat. Conclusions are made regarding the response of the annual CO2 and H2O conifer disc tree ring distributions to different climatic factors.

关键词： H2O CO2 cyclicity tree rings laser photoacoustic gas analysis climate response

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