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Upconversion FRET quantitation:the role of donor photoexcitation mode and compositional architecture on the decay and intensity based responses

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Light(Science & Applications) 2022年第10期11卷 2321-2334页

作者： Agata Mkotulska aleksandra Pilch-WrÓbel Satu Lahtinen Tero Soukka Artur Bednarkiewicz Division of Biomedical Physicochemistry Institute of Low Temperature and Structure ResearchPANul.Okolna 2Wroclaw 50-422Poland Department of Life Technologies/Biotechnology University of TurkuKiinamyllynkatu 1020520 TurkuFinland

Lanthanide-doped colloidal nanoparticles capable of photon upconversion(UC)offer long luminescence lifetimes,narrowband absorption and emission spectra,and efficient anti-Stokes *** features are highly advantageous for F?rster Resonance Energy Transfer(FRET)based *** nanoparticles(UCNPs)as donors may solve the existing problems of molecular FRET systems,such as photobleaching and limitations in quantitative analysis,but these new labels also bring new *** we have studied the impact of the core-shell compositional architecture of upconverting nanoparticle donors and the mode of photoexcitation on the performance of UC-FRET from UCNPs to Rose Bengal(RB)molecular *** have quantitatively compared luminescence rise and decay kinetics of Er3+emission using core-only NaYF4:20%Yb,2%Er and core-shell NaYF4:20%Yb@NaYF4:20%Yb,5%Er donor UCNPs under three photoexcitation schemes:(1)direct short-pulse photoexcitation of Er3+at 520 nm;indirect photoexcitation of Er3+through Yb3+sensitizer with(2)980 nm short(5-7 ns)or(3)980 nm long(4 ms)laser *** donor luminescence kinetics and steady-state emission spectra differed between the UCNP architectures and excitation *** for highly sensitive kinetic upconversion FRET-based biomolecular assays,the experimental results underline the complexity of the excitation and energy-migration mechanisms affecting the Er3+donor responses and suggest ways to optimize the photoexcitation scheme and the architecture of the UCNPs used as luminescent donors.

关键词： excitation donor decay

HIFs in hypoxic regulation of the extracellular matrix:focus on little-known player HIF-3

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BIOCELL 2024年第5期48卷 677-692页

作者： aleksandra GORNOSTAEVA LUDMILA BURAVKOVA MARGARITA LOBANOVA ELENA ANDREEVA Institute of Biomedical Problems of the Russian Academy of Sciences Khoroshevskoye Shosse 76AMoscow123007Russia

The structural and associated molecules of the extracellular matrix(ECM)complex is an important component of the local milieu of cells,both for maintaining their functions and *** is a dynamic structure that is finely tuned to changes in the *** of these factors is hypoxia,which can arise in tissues due to physiological or pathological *** a result of the hypoxic effect,the properties of the ECM are significantly modified,stiffness increases,the balance between degradation and synthesis of structural proteins shifts,and the deposition of biologically active mediators’***-inducible factors(HIFs)contribute significantly to the modification of the properties of the ECM under *** the three HIF isoforms,HIF-1 is the most studied,with numerous identified target genes encoding proteins that participate in all matrisome *** less is known about HIF-2 and *** the context of the effects of hypoxia on the matrisome,HIF-3 isoform is of particular *** the first two isoforms,transiently expressed during the first hours of hypoxia,HIF-3 is activated after around 24 h of exposure to hypoxia and persists for a longer *** addition,its transcription is more pronounced under hypoxia than are HIFs 1 and ***-3,rather than the first two isoforms,is possibly responsible for the changes that occur in matrisome during prolonged hypoxic *** review attempts to summarize the available data on the involvement of HIF-3 in the matrisome modification under hypoxia.

关键词： Hypoxia Hypoxia-inducible factors Matrisome

Instrumented and Vickers Indentation for the Characterization of Stiffness,Hardness and Toughness of Zirconia Toughened Al_2O_3 and SiC Armor

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Journal of Materials Science & Technology 2015年第8期31卷 773-783页

作者： aleksandra Nastic Ali Merati Mariusz Bielawski Manon Bolduc Olaniyi Fakolujo Michel Nganbe Department of Mechanical Engineering University of Ottawa National Research Council Canada Defence R&D Canada(DRDC Valcartier)

Instrumented and Vickers indentation testing and microstructure analysis were used to investigate zirconia toughened alumina （ZTA） and silicon carbide （SIC）. Several equations were studied to relate the Vickers indentation hardness, Young＇s modulus and crack behavior to the fracture toughness. The frac- ture in SiC is unstable and occurs primarily by cleavage leading to a relatively low toughness of 3 MPa m1/2, which may be inappropriate for multi-hit capability. ZTA absorbs energy by plastic deformation, pore collapse, crack deviation and crack bridging and exhibits time dependent creep. With a relatively high toughness around 6.6 MPa m1/2, ZTA is promising for multi-hit capability. The higher accuracy of median equations in calculating the indentation fracture toughness and the relatively high c/a ratios above 2.5 suggest median type cracking for both SiC and ZTA. The Young＇s modulus of both ceramics was most accurately measured at lower indentation loads of about 0.5 kgf, while more accurate hardness and fracture toughness values were obtained at intermediate and at higher indentation loads beyond 5 kgf, respectively. A strong indentation size effect （ISE） was observed in both materials. The load independent hardness of SiC is 2563 HV, putting it far above the standard armor hardness requirement of 1500 HV that is barely met by ZTA.

关键词： Zirconia toughened alumina Silicon carbide Armor Vickers indentation fracture toughness Elastic modulus Vickers hardness

Giant pseudoaneurysm of the splenic artery within walled of pancreatic necrosis on the grounds of chronic pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 87-89页

作者： Milica Mitrovic Jovanovic Dusan Saponjski aleksandra Djuric Stefanovic aleksandra Jankovic Stefan Milosevic Katarina Stosic Djordje Knezevic Jelena Kovac Department of Abdominal Radiology Center for Radiology and MRIClinical Center of SerbiaBelgradeSerbia Faculty of Medicine University of BelgradeBelgradeSerbia Clinic for Digestive Surgery–First Surgical Clinic Clinical Center of SerbiaBelgradeSerbia

Chronic pancreatitis is a long-standing inflammation of the pancreas,characterized by progressive inflammatory and fibrotic changes,resulting in permanent structural damage of pancreatic parenchyma[1].Pancreatitis(chronic or acute)is the primary risk factor for pseudo-splenic artery aneurysms,along with pancreatic pseudocysts and *** the disease progresses,patients with chronic pancreatitis may develop complications due to exocrine and endocrine pancreatic functional loss,such as fat malabsorption with steatorrhea,glucose intolerance,and ultimately diabetes mellitus[1,2].Furthermore,severe pancreatic inflammation can cause weakening of vessel walls,with subsequent formation of arterial *** artery is the most commonly affected visceral artery[2,3].Liver cirrhosis,portal hypertension,liver transplantation,atherosclerosis,hypertension,pregnancy and multiparity are main risk factors for true splenic artery aneurysms[2].Rupture and intraperitoneal bleeding is the cause of death in 30%−50%of ***,prompt diagnosis and appropriate treatment are of great clinical importance[4,5].Herein,we present a case of a giant splenic artery pseudoaneurysm within a walled of necrosis involving pancreatic parenchyma,as a complication of long standing chronic pancreatitis.

关键词： pancreatitis aneurysm inflammation

Environmental exposure to cadmium but not lead is associated with decreased semen quality parameters:quality regionalism of sperm properties

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Asian Journal of Andrology 2022年第1期24卷 26-31页

作者： Katarzyna Olszak-Wasik Andrzej Tukiendorf aleksandra Kasperczyk Artur Wdowiak Stanislaw Horak Department of Gynecology Obstetrics and Oncological Gynecology in BytomMedical University of SilesiaSchool of Medicine and Division of Dentistry in ZabrzeBatorego 15Bytom 41-902Poland Department of Public Health Wroclaw Medical UniversityBartla 5Wroclaw 51-618Poland Department of Biochemistry Medical University of SilesiaSchool of Medicine and Division of Dentistry in ZabrzeJordana 19Zabrze 41-808Poland Faculty of Health Sciences Diagnostic Techniques UnitMedical University of LublinStaszica 4/6Lublin 20-081Poland

Environmental factors may negatively contribute to a progressive worsening of semen quality,and differences in semen quality may result from different environmental exposures(regional differences)or lifestyle *** metals are factors with a confirmed negative influence on male *** them,lead and cadmium are commonly found in human ***,we analyzed semen parameters(according to the World Health Organization 2010 recommendations)and semen lead and cadmium concentrations in 188 men from two different regions in Poland,a typical agricultural area and an industrial area,in couples that had been diagnosed with *** assays were performed using flameless electrothermal atomic absorption *** the statistical analysis,regional comparisons and then taxonomic comparisons based on three parameters(age,semen concentration,and sperm morphology)were *** showed that more cadmium than lead accumulated in semen,a higher cadmium concentration was observed in semen obtained from men from the agricultural region,and better semen quality and lower cadmium concentrations were found in the semen of men from the industrial,more polluted *** thus showed an existing regionalism in the sperm quality ***,semen parameters such as morphology and progressive and nonprogressive motility followed the same trends,regardless of the patient’s age,region,or *** could conclude that the environment has a minor impact on sperm morphology and progressive and nonprogressive motility and that other existing factors could have an indirect influence on semen quality.

关键词： cadmium environment lead semen quality taxonomic analysis

Catalytic Kinetic Spectrophotometric Method for Determination of Phosphate Ion

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Chinese Journal of Chemistry 2007年第4期25卷 531-534页

作者： MITIC Snezana ZIVANOVIC Valentina OBRADOVIC Mirjana TOSIC Snezana PAVLOVIC aleksandra Faculty of Sciences and Mathematics Department of Chemistry University of Nig Visegradska 33 P.O. Box 224 18000 Nis Serbia

The kinetic method for the determination of phosphate microamounts was described. The developed method is based on catalytic effect of phosphate on sodium pyrogallol-5-sulphonate （PS） by dissolved oxygen. The reaction was followed spectrophotometrically by measuring the rate of change in the values of the absorbance of the oxidation product at 437 nm. The optimum reaction conditions are PS （0.44×10^-3 mol·L^-1） and HClO4 （3.6×10^-6 mol·L^-1） at 25 ℃. Following this procedure, phosphate can be determined with a linear calibration graph up to 0.23 μg·mL^-1. The interference effect of several species was also investigated and it was found that the most common cations and anions did not interfere with the determination. The developed procedure was successfully applied to the determination of phosphate in natural waters and soil.

关键词： kinetic spectrophotometric method sodium pyrogallol-5-sulphonate phosphate oxygen oxidation determination water soil

Role of environmental pollution in irritable bowel syndrome

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World Journal of Gastroenterology 2015年第40期21卷 11371-11378页

作者： Mateusz Marynowski aleksandra Likońska Hubert Zatorski Jakub Fichna Department of Biochemistry Faculty of MedicineMedical University of Lodz Mossakowski Medical Research Centre Polish Academy of Sciences

Irritable bowel syndrome(IBS),with the prevalence of 10%-20 % of the population has become an emerging problem worldwide. IBS is a functional gastrointestinal(GI) disorder characterized by abdominal pain or discomfort and altered bowel habits. The etiology of IBS contains genetic,psychological,and immunological factors,and has not been fully elucidated; of note,recent studies also point at environmental pollution and its role in the development of functional GI diseases. In this review we focus on several environmental factors,such as bacterial contamination,air pollution,radiation and even stress as potential triggers of IBS. We discuss associated disturbances in homeostasis,such as changes in intestinal microbiome and related pathophysiological mechanisms. Based on the effect of environmental factors on the GI tract,we also propose novel targets in IBS treatment.

关键词： Irritable bowel syndrome Environmental pollution A

Biogeography and Evolutionary Factors Determine Genetic Differentiation of Pinus mugo(Turra) in the Tatra Mountains(Central Europe)

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Journal of Mountain Science 2015年第3期12卷 549-557页

作者： CELINSKI Konrad ZBRáNKOVá Veronika WOJNICKA-PóLTORAK aleksandra CHUDZINSKA Ewa Department of Genetics Adam Mickiewicz University in Poznań Department of Biology and Ecology University of Ostrava

Inter Simple Sequence Repeats （ISSR） markers were used to assess genetic diversity within and among populations of dwarf mountain pine （Pinus rnugo Turra） growing in the Tatra National Park （UNESCO Biosphere Reserve） in Southern Poland （Central Europe）. The analyzed population belongs to two different geobotanical sub-districts： the Western and High Tatras. The level of genetic diversity assessed in this study for P. mugo is generally comparable to that reported for the other pine species in the Pinaceae family assessed by ISSR markers, especially with respect to Nei＇s genetic diversity and the percentage of polymorphic bands. Bayesian analysis clustered the analyzed populations into two groups, corresponding to their geobotanical locations in the Tatras. Significant divergence between the two genetical clusters was supported by the results of Analysis of Molecular Variance （AMOVA）. According to the Mantel test, there was no correlation between the genetic distance and the geographical distance. The present study confirms the existence of two genetically distinct dusters of P. mugo populations in the Tatra Mountains. The observed high population-genetic differentiation of *** in the Tatras could be attributed to several genetic, environmental and historical factors occurring in this mountain area.

关键词： Biogeography Conservation genetics The Tatra Mountains Pinus mugo

Immune defense of wild-caught Norway rats is characterized by increased levels of basal activity but reduced capability to respond to further immune stimulation

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Integrative Zoology 2018年第2期13卷 180-193页

作者： Ivana MIRKOV aleksandra POPOV ALEKSANDROV Vesna SUBOTA Dragan KATARANOVSKI Milena KATARANOVSKI Immunotoxicology Group Department of EcologyInstitute for Biological Research“Sinisa Stankovic”University of BelgradeBelgradeSerbia Institute for Medical Biochemistry Military Medical AcademyBelgradeSerbia Institute of Zoology Faculty of BiologyUniversity of BelgradeBelgradeSerbia Institute of Physiology and Biochemistry Faculty of BiologyUniversity of BelgradeBelgradeSerbia

Studies of wild animals’immunity often use comparison with laboratory-raised *** such an approach,various data were obtained concerning wild Norway rat’s *** or higher potential of immune system cells to respond to activation stimuli were shown,because of analysis of disparate parameters and/or small number of analyzed *** differences between laboratory and wild rats were shown too,owing to great response variability in wild *** hypothesized that wild rats will express more intense immune activity compared to their laboratory counterparts which live in a less demanding *** test this,we analyzed the circulating levels of inflammatory cytokine interleukin-6(IL-6),a mediator which has a central role in host immune *** addition,we examined the activity of the central immune organ,the spleen,including cell proliferation and production of pro-inflammatory cytokines interferon-γ(IFN-γ)and interleukin-17(IL-17),which are major effectors of cellular adaptive immune *** order to obtain reasonable insight into the immunity of wild Norway rats,analysis was conducted on a much larger number of individuals compared to other *** levels of plasma IL-6,higher spleen mass,cellularity and basal IFN-γproduction concomitantly with lower basal production of anti-inflammatory cytokine interleukin-10(IL-10)revealed more intense immune activity in the wild compared to laboratory ***,lower responsiveness of their spleen cells’proinflammatory cytokine production to concanavalin A(ConA)stimulation,along with preserved capacity of IL-10 response,might be perceived as an indication of wild rats’reduced capability to cope with incoming environmental stimuli,but also as a means to limit tissue damage.

关键词： circulating interleukin-6 levels spleen cell cytokine production spleen cell proliferation