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21.
Solution-processed hybrid organic–inorganic perovskite light-emitting transistors (PeLETs) suffer from low brightness and environmental instability induced by temperature-activated trapping, ionic motion, and polarization effects, which so far have been hindering the realization of devices operating at room temperature. Here high quality thermally co-evaporated methylammonium lead iodide perovskite films are employed to minimize ionic motion and significantly improve the electroluminescence characteristics of the perovskite active layer, enabling stable device operation up to ≈ 310 K. The demonstration of PeLETs operating at and beyond room-temperature paves the way for practical applications in the rapidly evolving area of solid-state lighting, active-matrix displays, and visible light communications. 相似文献
22.
Marchand B Douek PC Robert P Corot C Roux JP Adeleine P Hernandez-Hoyos M Cremillieux Y Orkisz M Canet E 《Magma (New York, N.Y.)》2002,14(3):259-267
Purpose To investigate the relative role of high resolution (spatial or temporal) magnetic resonance angiography (MRA) sequence and
of contrast agent properties in the evaluation of high-degree arterial stenosis.
Methods We qualitatively and quantitatively studied both 50 and 95% (300 μm diameter) stenosis of a 6 mm arterial phantom with two
contrast agents (CA), Gd-DOTA (r1 =2.9 mM−1 s−1) versus P760 (r1 =25 mM−1 s−1) at several CA concentrations, including arterial peak concentration after injection of either a single or double dose of
CA, using either a high temporal (booster) or high spatial (HR) resolution 3D MRA sequences. Experimental data were then compared
to theoretical data.
Results With the 3D HR sequence, both visual and quantitative analysis were significantly better compared to the 3D booster sequence,
at each phantom diameter. Quantitative analysis was significantly improved by injection of a double versus a single dose of
each CA (Gd-DOTA or P760), primarily in high degree stenosis.
Conclusion Combined MRA spatial resolution and high CA efficiency are mandatory to correctly evaluate high degree stenosis. 相似文献
23.
Kamila Checinska Maciej Checinski Katarzyna Cholewa-Kowalska Maciej Sikora Dariusz Chlubek 《International journal of molecular sciences》2022,23(13)
One of the possible alternatives for creating materials for the regeneration of bone tissue supporting comprehensive reconstruction is the incorporation of active substances whose controlled release will improve this process. This systematic review aimed to identify and synthesize in vitro studies that assess the suitability of polyphenolics as additives to polymer-ceramic composite bone regeneration materials. Data on experimental studies in terms of the difference in mechanical, wettability, cytocompatibility, antioxidant and anti-inflammatory properties of materials were synthesized. The obtained numerical data were compiled and analyzed in search of percentage changes of these parameters. The results of the systematic review were based on data from forty-six studies presented in nineteen articles. The addition of polyphenolic compounds to composite materials for bone regeneration improved the cytocompatibility and increased the activity of early markers of osteoblast differentiation, indicating a high osteoinductive potential of the materials. Polyphenolic compounds incorporated into the materials presumably give them high antioxidant properties and reduce the production of reactive oxygen species in macrophage cells, implying anti-inflammatory activity. The evidence was limited by the number of missing data and the heterogeneity of the data. 相似文献
24.
Mateusz Sypniewski Zbigniew J. Krl Joanna Szyda Elbieta Kaja Magdalena Mroczek Tomasz Suchocki Adrian Lejman Maria St&#x;pie&#x; Piotr Topolski Maciej D&#x;browski Krzysztof Kotlarz Angelika Aplas Micha&#x; Wasiak Marzena Wojtaszewska Pawe&#x; Zawadzki Agnieszka Pawlak Robert Gil Paula Dobosz Joanna Stojak 《International journal of molecular sciences》2022,23(15)
Background: Severe outcomes of COVID-19 account for up to 15% of all cases. The study aims to check if any gene variants related to cardiovascular (CVD) and pulmonary diseases (PD) are correlated with a severe outcome of COVID-19 in a Polish cohort of COVID-19 patients. Methods: In this study, a subset of 747 samples from unrelated individuals collected across Poland in 2020 and 2021 was used and whole-genome sequencing was performed. Results: The GWAS analysis of SNPs and short indels located in genes related to CVD identified one variant significant in COVID-19 severe outcome in the HADHA gene, while for the PD gene panel, we found two significant variants in the DRC1 gene. In this study, both potentially protective and risk variants were identified, of which variants in the HADHA gene deserve the most attention. Conclusions: This is the first study reporting the association between the HADHA and DRC1 genetic variants and COVID-19 severe outcome based on the cohort WGS analysis. Although all the identified variants are localised in introns, they may be correlated and therefore inherited along with other risk variants, potentially causative to severe outcome of COVID-19 but not discovered yet. 相似文献
25.
Klaudia Kwieci&#x;ska Anna Stachowicz-Ku nierz Beata Korchowiec Maciej Roman Wojciech M. Kwiatek Anna Jagusiak Irena Roterman Jacek Korchowiec 《International journal of molecular sciences》2022,23(16)
The uptake and distribution of doxorubicin in the MCF7 line of breast-cancer cells were monitored by Raman measurements. It was demonstrated that bioavailability of doxorubicin can be significantly enhanced by applying Congo red. To understand the mechanism of doxorubicin delivery by Congo red supramolecular carriers, additional monolayer measurements and molecular dynamics simulations on model membranes were undertaken. Acting as molecular scissors, Congo red particles cut doxorubicin aggregates and incorporated them into small-sized Congo red clusters. The mixed doxorubicin/Congo red clusters were adsorbed to the hydrophilic part of the model membrane. Such behavior promoted transfer through the membrane. 相似文献
26.
Katarzyna ycie&#x;ska Beata Pszcz&#x;kowska Beata Brzozowska Maciej Kami&#x;ski Tomasz Lorenc Wioletta Olejarz S&#x;awomir S&#x;k Jzef Ginter 《International journal of molecular sciences》2022,23(17)
Extracellular vesicles are evaluated by nanoparticle tracking analysis (NTA), providing information on their hydrodynamic diameters, and by atomic force microscopy (AFM) to calculate their geometric diameters. The aim of this study is to explore the influence of Brownian movements in a sample drop and preparation time on imaging-based measurements and to determine the relationship between the geometric and hydrodynamic sizes of the extracellular vesicles measured by the AFM and the NTA, respectively. Exosomes derived from the human prostate cancer cell line PC3 were evaluated by NTA and AFM, and those results were compared with Monte Carlo simulations. The mean size, evaluated by AFM shortly after application on the mica substrate, is less than its real value. It obtains the correct value faster for a thinner sample drop. Fitting the log-normal distribution to the geometric and hydrodynamic diameters leads to the conclusion that the latter could arise from the former by linear scaling by a factor that could be used to characterize the analyzed extracellular vesicles. The size of the vesicles attached to the mica substrate depends on time. The effect of Brownian motion and stretch of the lipid bilayer should be considered in the context of exosome AFM studies. 相似文献
27.
Julita Gumna Maciej Antczak Ryszard W. Adamiak Janusz M. Bujnicki Shi-Jie Chen Feng Ding Pritha Ghosh Jun Li Sunandan Mukherjee Chandran Nithin Katarzyna Pachulska-Wieczorek Almudena Ponce-Salvatierra Mariusz Popenda Joanna Sarzynska Tomasz Wirecki Dong Zhang Sicheng Zhang Tomasz Zok Eric Westhof Zhichao Miao Marta Szachniuk Agnieszka Rybarczyk 《International journal of molecular sciences》2022,23(17)
RNA is a unique biomolecule that is involved in a variety of fundamental biological functions, all of which depend solely on its structure and dynamics. Since the experimental determination of crystal RNA structures is laborious, computational 3D structure prediction methods are experiencing an ongoing and thriving development. Such methods can lead to many models; thus, it is necessary to build comparisons and extract common structural motifs for further medical or biological studies. Here, we introduce a computational pipeline dedicated to reference-free high-throughput comparative analysis of 3D RNA structures. We show its application in the RNA-Puzzles challenge, in which five participating groups attempted to predict the three-dimensional structures of 5- and 3-untranslated regions (UTRs) of the SARS-CoV-2 genome. We report the results of this puzzle and discuss the structural motifs obtained from the analysis. All simulated models and tools incorporated into the pipeline are open to scientific and academic use. 相似文献
28.
Joanna Kisa&#x;a Anna Tomaszewska Adriana Barylyak Yaroslav Bobitski Maciej Balawejder 《International journal of molecular sciences》2022,23(7)
Flame retardants have attracted growing environmental concern. Recently, an increasing number of studies have been conducted worldwide to investigate flame-retardant sources, environmental distribution, living organisms’ exposure, and toxicity. The presented studies include the degradation of 4,4′-isopropylidenebis(2,6-dibromophenol) (TBBPA) by ozonolysis and photocatalysis. In the photocatalytic process, nano- and micro-magnetite (n-Fe3O4 and μ-Fe3O4) are used as a catalyst. Monitoring of TBBPA decay in the photocatalysis and ozonolysis showed photocatalysis to be more effective. Significant removal of TBBPA was achieved within 10 min in photocatalysis (ca. 90%), while for ozonation, a comparable effect was observed within 70 min. To determine the best method of TBBPA degradation concentration on COD and TOC, the removals were examined. The highest oxidation state was obtained for photocatalysis on μ-Fe3O4, whereas for n-Fe3O4 and ozonolysis, the COD/TOC ratio was lower. Acute toxicity results show noticeable differences in the toxicity of TBBPA and its degradation products to Artemia franciscana and Thamnocephalus platyurus. The EC50 values indicate that TBBPA degradation products were toxic to harmful, whereas the TBPPA and post-reaction mixtures were toxic to the invertebrate species tested. The best efficiency in the removal and degradation of TBBPA was in the photocatalysis process on μ-Fe3O4 (reaction system 1). The examined crustaceans can be used as a sensitive test for acute toxicity evaluation. 相似文献
29.
Grzegorz K. Przybylski Dorota Korsak Katarzyna Iykowska Karina Nowicka Tomasz Zalewski Ma&#x;gorzata Tubacka Maria Mosor Danuta Januszkiewicz-Lewandowska Magdalena Frydrychowicz Maciej Boruczkowski Grzegorz Dworacki Jens van den Brandt Piotr Grabarczyk Christian A. Schmidt Chengwu Zeng Yangqiu Li 《International journal of molecular sciences》2022,23(9)
30.
Daria Wojciechowska Micha&#x; Taube Karolina Ruci&#x;ska Joanna Maksim Maciej Kozak 《International journal of molecular sciences》2022,23(21)
Human cystatin C (HCC), an amyloidogenic protein, forms dimers and higher oligomers (trimers, tetramers and donut like large oligomers) via a domain-swapping mechanism. The aim of this study was the characterization of the HCC oligomeric states observed within the pH range from 2.2 to 10.0 and also in conditions promoting oligomerization. The HCC oligomeric forms obtained in different conditions were characterized using size exclusion chromatography, dynamic light scattering and small-angle X-ray scattering. The marked ability of HCC to form tetramers at low pH (2.3 or 3.0) and dimers at pH 4.0–5.0 was observed. HCC remains monomeric at pH levels above 6.0. Based on the SAXS data, the structure of the HCC tetramer was proposed. Changes in the environment (from acid to neutral) induced a breakdown of the HCC tetramers to dimers. The tetrameric forms of human cystatin C are formed by the association of the dimers without a domain-swapping mechanism. These observations were confirmed by their dissociation to dimers at pH 7.4. 相似文献