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Cytotoxicity and non-specific cellular uptake of bare and surface-modified upconversion nanoparticles in human skin cells

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Nano Research 2015年第5期8卷 1546-1562页

作者： Anna E. Guller Alia N. Generalova Elena V. Petersen Andrey V. Nechaev Inna A. Trusova nikolay N. Landyshev Annemarie Nadort Ekaterina A. Grebenik Sergey m. Deyev Anatoly B. Shekhter Andrei V. Zvyagin macquarie University Australia I.m. Sechenov First moscow State medical University Russia Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences Russia Nizhny Novgorod State University Russia moscow Institute of Physics and Technology Russia moscow State University of Fine Chemical Technologies Russia University of Amsterdam the Netherlands

The cytotoxicity and non-specific cellular uptake of the most popular composition of upconversion nanoparticle （UCNP）, NaYF4：Yb^3＋：Er^3＋, is reported using normal human skin cells, including dermal fibroblasts and immortalized human epidermal linear keratinocytes （HaCaT）. A new hydrophilization reaction of as-synthesized UCNPs based on tetramethylammonium hydroxide （TmAH） enabled evaluation of the intrinsic cytotoxicity of bare UCNPs. The cytotoxicity effects of the UCNP surface-coating and polystyrene host were investigated over the concentration range 62.5-125 μg/mL with 24-h incubation, using a mTT test and optical microscopy. The fibroblast viability was not compromised by UCNPs, whereas the viability of keratinocytes varied from 52% ± 4% to 100% ± 10% than the control group, depending on the surface modification. Bare UCNPs reduced the keratinocyte viability to 76% ± 3%, while exhibiting profound non-specific cellular uptake. Hydrophilic poly（D,L-lactide）- and poly（maleic anhydride-alt-l-octadecene）-coated UCNPs were found to be least cytotoxic among the polymer-coated UCNPs, and were readily internalized by human skin cells. Polystyrene microbeads impregnated with UCNPs remained nontoxic. Surprisingly, no correlation was found between UCNP cytotoxicity and the internalization level in cells, although the latter ranged broadly from 0.03% to 59%, benchmarked against 100% uptake level of TmAH-UCNPs.

关键词： nanoparticle upconversion surface modification biocompatibility cytotoxicity human skin

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On the Ionization Energy of the Outer Electrons of Atoms and Their Ions

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Journal of modern Physics 2013年第11期4卷 1486-1489页

作者： nikolay D. Gudkov Vladimir A. Shuvalov 1Institute of Basic Biological Problems Russian Academy of Sciences Pushchino Russia 2A.N. Belozersky Institute of Physico-Chemical Biology M.V. Lomonosov Moscow State University Moscow Russia Institute of Basic Biological Problems Russian Academy of Sciences Pushchino Russia

An empirical formula is proposed to calculate the total binding energy of the outer electrons of atoms and their ions to a high accuracy. It is the authors’ opinion that the validity of the proposed formula testifies that electronic shells have some “spatial structures”, and the nature of which depends neither on the nucleus charge, nor on the number of the electrons in a shell.

关键词： Complex Atoms Electronic Shells Ionization Energy

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Exploring Sequence Space to Design Controllable G-Quadruplex Topology Switches

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CCS Chemistry 2022年第9期4卷 3036-3050页

作者： Jielin Chen mingpan Cheng petr Stadlbauer JiříŠponer Jean-Louis mergny Huangxian Ju Jun Zhou State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023 Institute of Biophysics of the Czech Academy of Sciences Královopolská135Brno 61265 Regional Centre of Advanced Technologies and materials Czech Advanced Technology and Research Institute(CATRIN)Palacky University OlomoucŠlechtitelů241/27Olomouc–Holice 78371 Laboratoire d’Optique et Biosciences Ecole PolytechniqueCNRSINSERMInstitut Polytechnique de ParisPalaiseau 91128

As nonclassical nucleic acid structures,G-quadruplexes(G4s)not only play important roles in gene regulation and stability maintenance,but are also widely used in *** diversity is one of the main factors explaining the popularity of G4s,but a comprehensive and integrated study of different factors determining G4 structural versatility is currently lacking.

关键词： G-quadruplex G-quadruplex topology Gswitch sequence composition structural versatility

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SIRT1-dependent modulation of methylation and acetylation of histone H3 on lysine 9(H3K9)in the zygotic pronuclei improves porcine embryo development

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Journal of Animal Science and Biotechnology 2018年第2期9卷 339-350页

作者： Katerina Adamkova Young-Joo Yi Jaroslav petr Tereza Zalmanova Kristyna Hoskova Pavla Jelinkova Jiri moravec milena Kralickova miriam Sutovsky Peter Sutovsky Jan Nevoral Department of Veterinary Sciences Faculty of AgricultureFood and Natural ResourcesCzech University of Life Sciences Prague6-SuchdolPragueCzech Republic Division of Biotechnology SafetyEnvironment and Life Science InstituteCollege of Environmental and Bioresource SciencesChonbuk National UniversityIksan 54596South Korea Institute of Animal Science 10-UhrinevesPragueCzech Republic Proteomic Laboratory Biomedical Center of Faculty of Medicine in PilsenCharles UniversityPilsenCzech Republic Laboratory of Reproductive medicine of Biomedical Center Charles UniversityPilsenCzech Republic Department of Histology and Embryology Faculty of Medicine in PilsenCharles UniversityPilsenCzech Republic Division of Animal Science University of MissouriColumbiaMOUSA Departments of Obstetrics Gynecology and Women’s HealthUniversity of MissouriColumbiaMOUSA

Background: The histone code is an established epigenetic regulator of early embryonic development in *** lysine residue K9 of histone H3(H3 K9) is a prime target of SIRT1, a member of NAD+-dependent histone deacetylase family of enzymes targeting both histone and non-histone substrates. At present, little is known about SIRT1-modulation of H3 K9 in zygotic pronuclei and its association with the success of preimplantation embryo development. Therefore, we evaluated the effect of SIRT1 activity on H3 K9 methylation and acetylation in porcine zygotes and the significance of H3 K9 modifications for early embryonic ***: Our results show that SIRT1 activators resveratrol and BmL-278 increased H3 K9 methylation and suppressed H3 K9 acetylation in both the paternal and maternal pronucleus. Inversely, SIRT1 inhibitors nicotinamide and sirtinol suppressed methylation and increased acetylation of pronuclear H3 K9. Evaluation of early embryonic development confirmed positive effect of selective SIRT1 activation on blastocyst formation rate(5.2 ± 2.9% versus 32.9 ± 8.1% in vehicle control and BmL-278 group, respectively; P ≤ 0.05). Stimulation of SIRT1 activity coincided with fluorometric signal intensity of ooplasmic ubiquitin ligase mDm2, a known substrate of SIRT1 and known limiting factor of epigenome ***: We conclude that SIRT1 modulates zygotic histone code, obviously through direct deacetylation and via non-histone targets resulting in increased H3 K9 me3. These changes in zygotes lead to more successful pre-implantation embryonic development and, indeed, the specific SIRT1 activation due to BmL-278 is beneficial for in vitro embryo production and blastocyst achievement.

关键词： Embryonic development Epigenetics H3K9 methylation SIRT1 Sirtuin

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Stimulation of decidua development by transplantation of endometrial stem cells

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Journal of Biomedical Science and Engineering 2013年第8期6卷 59-65页

作者： Alisa P. Domnina Victoria I. Zemelko Vyacheslav m. mikhailov nikolay N. Nikolsky Institute of Cytology Russian Academy of Sciences St.-Petersburg Russia

On all terms of pregnancy, insolvency of decidual reaction of endometrial cells is one of the reasons of miscarriages and fetal growth delay. The insufficient decidualization of endometrum leads to infertility in such pathologies, as Asherman’s syndrome and an endometrium atrophy. However, there are data on successful application of autologous bone marrow mSCs for Asherman’s syndrome treatment. The aim of this work was to assay the effect of endometrial mesenchymal stem cell (emSC) transplantation for decidualization process in pseudopregnant rat. Our study showed that injection of human emSC suspension into the uterine lumen of pseudopregnant rats facilitated more intensive development of decidua in comparison with phosphate buffed saline (PBS) injection in the control uterine horn. Histological analysis of decidua sections did not reveal any alterations in cell differentiation or tissue structure. In conclusion, we demonstrated for the first time that emSC transplantation assists the development of all decidual tissue elements. It opens the possibility that emSCs may be applied for cell therapy of infertility associated with decidualzation insufficiency.

关键词： Decidualization Pseudopregnancy Human mesenchymal Stem Cells of Endometrium menstrual Blood

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All-optical dynamic focusing of light via coherent absorption in a plasmonic metasurface

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Light(Science & Applications) 2017年第1期6卷 114-120页

作者： maria Papaioannou Eric Plum Edward TF Rogers nikolay I Zheludev Optoelectronics Research Centre and Centre for Photonic metamaterials University of SouthamptonHighfieldSouthampton SO171BJUK Institute for Life Sciences University of SouthamptonHighfieldSouthampton SO171BJUK Centre for Disruptive Photonic Technologies School of Physical and Mathematical Sciences and The Photonics InstituteNanyang Technological UniversitySingapore 637371Singapore

Vision,microscopy,imaging,optical data projection and storage all depend on focusing of *** focusing is conventionally achieved with mechanically reconfigurable lenses,spatial light modulators or *** we demonstrate that dynamic control of focusing can be achieved through coherent interaction of optical waves on a thin beam *** use a nanostructured plasmonic metasurface of subwavelength thickness as the beam splitter,allowing operation in the regimes of coherent absorption and coherent *** of light resulting from illumination of the plasmonic metasurface with a Fresnel zone pattern is controlled by another patterned beam projected on the same *** altering the control pattern,its phase,or its intensity,we switch the lens function on and off,and alter the focal spot’s depth,diameter and *** occurs as fast as the control beam is modulated and therefore tens of gigahertz modulation bandwidth is possible with electro-optical modulators,which is orders of magnitude faster than conventional dynamic focusing technologies.

关键词： all-optical dynamic focusing coherent control coherent perfect absorption metasurfaces

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Different Carbon Fractions in Soils and Their Relationship with Trace Elements Content

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Journal of Life Sciences 2011年第4期5卷 316-321页

作者： Lubica Pospisilova petr Skarpa marie Konecna Department of Agrochemistry Soil Science Microbiology and Plant Nutrition Faculty of Agriculture Mendel University in BrnoZem~ddlsk6 1 Brno 613 00 Czech Republic

Luvisols, Stagnogleys and Cambisols, although less fertile, are used intensively for mixed farming, grazing and as forestland. Therefore we aimed our study at determination of total organic carbon （TOC） content, humic substances （HS） content, humic acids （HA） content, fulvic acids （FA）, hot water extractable carbon （Chw） content and content total and labile trace elements content. Humic substances quality was assessed by HA/FA ratio and by coloured indexes measured in ultraviolet and visible UV-VIS spectral range. The total and labile contents of Zn, Cd, Cu, Co, Pb, mo and Se were determined by flame or electro-thermal atomic absorption spectrometry after extraction of the soil samples in the aqua regia （total content） and in the solution of 0.01 m CaCI2. Total and labile trace elements content was correlated with determined carbon fractions and soil reaction. Results showed that studied soils content low amount of TOC and had low quality of humic substances. HA/FA ratio was less than 1 and colour indexes were higher than 4. All determined carbon fractions correlated with labile form of Zn and Cd. Correlation between soil reaction and total zinc content was found. Significant effect of humic substances content on to water-soluble forms of heavy metals was detected.

关键词： Humic acids fulvic acids hot water extractable carbon humus fractionation labile trace elements total trace elements.

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Quantum Conductance Staircase of Edge Hole Channels in Silicon Quantum Wells

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Journal of modern Physics 2012年第11期3卷 1771-1775页

作者： nikolay T. Bagraev Leonid E. Klyachkin Andrei A. Kudryavtsev Anna m. malyarenko Ioffe Physical Technical Institute St. Petersburg Russia

We present the findings for the quantum conductance staircase of holes that is caused by the edge channels in the ultra-shallow p-type silicon quantum well (Si-QW), 2 nm, confined by the δ-barriers heavily doped with boron on the n-type Si (100) surface. This longitudinal quantum conductance staircase, Gxx, is revealed by the voltage applied to the Hall contacts, Vxy, to a maximum of 4e2/h. In addition to the standard plateau, 2e2/h, the variations of the Vxy voltage appear to exhibit the fractional forms of the quantum conductance staircase with the plateaus and steps that bring into correlation respectively with the odd and even fractional values.

关键词： Quantum Conductance Staircase Edge Channels Silicon Nanosandwich Odd and Even Fractional Values

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Real-World Safety and Performance of Saline Nasal Spray Products for Nasal Cleansing and Reducing Obstruction of the Nasal Cavity

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Open Journal of Respiratory Diseases 2023年第4期13卷 65-79页

作者： mathieu m. Albasser Gary Smith mariane Ballerini Fernandes Nisha Patel petr Novak martina Hagen GSK Consumer Healthcare SARL a Haleon company Nyon Switzerland Haleon Weybridge Surrey UK GSK Kingston upon Thames London UK Haleon Prague Czech Republic

Background and Objectives: Three post-marketing clinical follow-up studies were performed in Europe to confirm the safety and performance of four nonprescription, nasal cleansing medical devices: Otrivin Sea Water (OSW) pressurized spray, OSW with aloe vera (OSWAV), Otrisal 0.74% NaCl metered-Dose Spray (mDS), and Prorhinel spray. material and methods: Observational, single-arm, retrospective studies consisting of a single online questionnaire were performed between July 2021 and December 2021. Eligible participants were adults who used the device or supervised use of the device in a participant under 18 years of age within 6 months of completing the questionnaire. Demographics, safety, and device performance were assessed. Results: Based on questionnaires submitted on OSW (n = 556), OSWAV (n = 555), Otrisal mDS (n = 555), and Prorhinel (n = 555), proportions of users who reported safety events were 1.8% for OSW, 2.3% for OSWAV, 1.4% for Otrisal mDS, and 2.0% for Prorhinel. Proportions of users who indicated they were satisfied or very satisfied with device performance ranged from 72.0% - 89.0% across all devices. Device performance for all products was also supported for additional preventative and symptomatic uses through exploratory analyses. Conclusions and Significance: These data confirm device safety and performance of OSW, OSWAV, Otrisal mDS, and Prorhinel for their intended uses.

关键词： Saline Solution Sodium Chloride Common Cold Allergens Postmarketing Product Surveillance

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Resveratrol modifies biliary secretion of cholephilic compounds in sham-operated and cholestatic rats

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World Journal of Gastroenterology 2017年第43期23卷 7678-7692页

作者： Eva Dolezelova Alena Prasnicka Jolana Cermanova Alejandro Carazo Lucie Hyrsova milos Hroch Jaroslav mokry michaela Adamcova Alena mrkvicova petr Pavek Stanislav micuda Department of Biological and medical Sciences Charles UniversityFaculty of Pharmacy in Hradec Kralove Department of Pharmacology Charles UniversityFaculty of Medicine in Hradec Kralove Department of Pharmacology and Toxicology Charles UniversityFaculty of Pharmacy in Hradec Kralove Department of medical Biochemistry Charles UniversityFaculty of Medicine in Hradec Kralove Department of Histology and Embryology Charles UniversityFaculty of Medicine in Hradec Kralove Department of Physiology Charles UniversityFaculty of Medicine in Hradec Kralove

AIm To investigate the effect of resveratrol on biliary secretion of cholephilic compounds in healthy and bile duct-obstructed rats. mETHODS Resveratrol(RSV) or saline were administered to rats by daily oral gavage for 28 d after sham operation or reversible bile duct obstruction(BDO). Bile was collected 24 h after the last gavage during an intravenous bolus dose of the mdr1/mrp2 substrate azithromycin. Bile acids,glutathione and azithromycin were measured in bile to quantify their level of biliary secretion. Liver expression of enzymes and transporters relevant for bile production and biliary secretion of major bile constituents and drugs were analyzed at the m RNA and protein levels using q RT-PCR and Western blot analysis,respectively. The TR-FRET PXR Competitive Binding Assay kit was used to determine the agonism of RSV at the pregnane X receptor. RESULTS RSV increased bile flow in sham-operated rats due to increased biliary secretion of bile acids(BA) and glutathione. This effect was accompanied by the induction of the hepatic rate-limiting transporters for bile acids and glutathione,Bsep and mrp2,respectively. RSV also induced Cyp7 a1,an enzyme that is crucial for bile acid synthesis; mrp4,a transporter important for BA secretion from hepatocytes to blood; and mdr1,the major apical transporter for xenobiotics. The findings were supported by increased biliary secretion of azithromycin. The TR-FRET PXR competitive binding assay confirmed RSV as a weak agonist of the human nuclear receptor PXR,which is a transcriptional regulator of mdr1/mrp2. RSV demonstrated significant hepatoprotective properties against BDO-induced cirrhosis. RSV also reduced bile flow in BDO rats without any corresponding change in the levels of the transporters and enzymes involved in RSV-mediated hepatoprotection. CONCLUSION Resveratrol administration for 28 d has a distinct effect on bile flow and biliary secretion of cholephilic compounds in healthy and bile duct-obstructed rats.

关键词： Resveratrol Bile production Bile acids Pregnane X receptor Azithromycin

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