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991.
Katarzyna Kotfis Jowita Biernawska Ma?gorzata Zegan-Barańska Maciej ?ukowski 《International journal of molecular sciences》2015,16(5):10077-10094
Background: The aim of the study was to evaluate the differences in the circulating immune cells’ subgroups after the atherosclerotic plaque removal in patients presenting with postoperative complications as compared to the patients without complications after carotid endarterectomy (CEA). Methods: Patients with significant carotid atherosclerosis (n = 124, age range: 44 to 87 years) who underwent CEA were enrolled in a prospective study. The immunology study using flow cytometry was performed to determine the percentages of peripheral blood T cells (CD4+, CD8+, Treg—CD4+/CD25+) and NK (natural killer) cells before and after the procedure. The data were expressed as the percentage of total lymphocytes ± the standard error of mean. Results: The mean percentage of lymphocytes (61.54% ± 17.50% vs. 71.82% ± 9.68%, p = 0.030) and CD4 T lymphocytes (T helper, 38.13% ± 13.78% vs. 48.39% ± 10.24%, p = 0.027) was significantly lower six hours after CEA in patients with postoperative 30-day cardiovascular and neurological complications as compared to the group without complications. On the other hand the mean NK level in the group with complications was significantly higher (21.61% ± 9.00% vs. 15.80% ± 9.31%, p = 0.048). Conclusions: The results of this study suggest that after carotid endarterectomy the percentages of circulating immune cells subsets differ in patients with and without postoperative complications. 相似文献
992.
Piotr Bedowski Maciej Przybyek Przemysaw Raczyski Andra Dedinaite Krzysztof Grny Florian Wieland Zbigniew Dendzik Alina Sionkowska Per M. Claesson 《International journal of molecular sciences》2021,22(22)
The lubrication mechanism in synovial fluid and joints is not yet fully understood. Nevertheless, intermolecular interactions between various neutral and ionic species including large macromolecular systems and simple inorganic ions are the key to understanding the excellent lubrication performance. An important tool for characterizing the intermolecular forces and their structural consequences is molecular dynamics. Albumin is one of the major components in synovial fluid. Its electrostatic properties, including the ability to form molecular complexes, are closely related to pH, solvation, and the presence of ions. In the context of synovial fluid, it is relevant to describe the possible interactions between albumin and hyaluronate, taking into account solution composition effects. In this study, the influence of Na+, Mg2+, and Ca2+ ions on human serum albumin–hyaluronan interactions were examined using molecular dynamics tools. It was established that the presence of divalent cations, and especially Ca2+, contributes mostly to the increase of the affinity between hyaluronan and albumin, which is associated with charge compensation in negatively charged hyaluronan and albumin. Furthermore, the most probable binding sites were structurally and energetically characterized. The indicated moieties exhibit a locally positive charge which enables hyaluronate binding (direct and water mediated). 相似文献
993.
994.
Prof. Dr.-Ing. Viktor Mechtcherine Dipl.-Ing. Alexander Kuhn Prof. Dr.-Ing. Inka Mai Dr.-Ing. Venkatesh Naidu Nerella Dr.-Ing. Daniel Weger M.Sc. Egor Ivaniuk Prof. Dr.-Ing. Udo Wiens 《Beton- und Stahlbetonbau》2024,119(4):290-310
Additive manufacturing with concrete – guidance for planning and implementation of projects This guideline, created by the DAfStb Working Group “Digital Concrete Construction through Additive Manufacturing,” serves as a comprehensive resource to support the planning and implementation of additive manufacturing projects in concrete construction. It is intended for architects, planners, applicants, material manufacturers, construction companies, and other parties involved in construction. After a brief introduction to the classification, terminology, and methods of additive manufacturing, legal aspects and approval procedures are highlighted to ensure seamless integration of this technology into construction practice. The guide addresses the integration of additive manufacturing methods with concrete into construction law, explains the approval process, and offers assistance for coordinating responsibilities in projects. It addresses technical rules for the design and construction of structures, particularly for walls produced by additive manufacturing, and covers constructive aspects of reinforcement. An important component is concrete and component testing, including methods for sample preparation and testing procedures for fresh and hardened concrete, making the guide a useful tool for professionals in the field of digital concrete construction. 相似文献
995.
Katarzyna Fiedorowicz Weronika Wargocka-Matuszewska Karolina A. Ambrokiewicz Anna Rugowska ukasz Cheda Micha Fiedorowicz Agnieszka Zimna Monika Drabik Szymon Borkowski Maciej
witkiewicz Piotr Bogorodzki Pawe Grieb Paulina Hamankiewicz Tomasz J. Kolanowski Natalia Rozwadowska Urszula Kozowska Aleksandra Klimczak Jerzy Kolasiski Zbigniew Rogulski Maciej Kurpisz 《International journal of molecular sciences》2021,22(19)
Current treatment protocols for myocardial infarction improve the outcome of disease to some extent but do not provide the clue for full regeneration of the heart tissues. An increasing body of evidence has shown that transplantation of cells may lead to some organ recovery. However, the optimal stem cell population has not been yet identified. We would like to propose a novel pro-regenerative treatment for post-infarction heart based on the combination of human skeletal myoblasts (huSkM) and mesenchymal stem cells (MSCs). huSkM native or overexpressing gene coding for Cx43 (huSKMCx43) alone or combined with MSCs were delivered in four cellular therapeutic variants into the healthy and post-infarction heart of mice while using molecular reporter probes. Single-Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) performed right after cell delivery and 24 h later revealed a trend towards an increase in the isotopic uptake in the post-infarction group of animals treated by a combination of huSkMCx43 with MSC. Bioluminescent imaging (BLI) showed the highest increase in firefly luciferase (fluc) signal intensity in post-infarction heart treated with combination of huSkM and MSCs vs. huSkM alone (p < 0.0001). In healthy myocardium, however, nanoluciferase signal (nanoluc) intensity varied markedly between animals treated with stem cell populations either alone or in combinations with the tendency to be simply decreased. Therefore, our observations seem to show that MSCs supported viability, engraftment, and even proliferation of huSkM in the post-infarction heart. 相似文献
996.
Aleksandra Szczepkowska Maciej Wjcik Dorota Tomaszewska-Zaremba Hanna Antushevich Agata Krawczyska Wiktoria Wiechetek Janina Skipor Andrzej Przemysaw Herman 《International journal of molecular sciences》2021,22(24)
This study was designed to determine the effect of acute caffeine (CAF) administration, which exerts a broad spectrum of anti-inflammatory activity, on the synthesis of pro-inflammatory cytokines and their receptors in the hypothalamus and choroid plexus (ChP) during acute inflammation caused by the injection of bacterial endotoxin—lipopolysaccharide (LPS). The experiment was performed on 24 female sheep randomly divided into four groups: control; LPS treated (iv.; 400 ng/kg of body mass (bm.)); CAF treated (iv.; 30 mg/kg of bm.); and LPS and CAF treated. The animals were euthanized 3 h after the treatment. It was found that acute administration of CAF suppressed the synthesis of interleukin (IL-1β) and tumor necrosis factor (TNF)α, but did not influence IL-6, in the hypothalamus during LPS-induced inflammation. The injection of CAF reduced the LPS-induced expression of TNF mRNA in the ChP. CAF lowered the gene expression of IL-6 cytokine family signal transducer (IL6ST) and TNF receptor superfamily member 1A (TNFRSF1) in the hypothalamus and IL-1 type II receptor (IL1R2) in the ChP. Our study on the sheep model suggests that CAF may attenuate the inflammatory response at the hypothalamic level and partly influence the inflammatory signal generated by the ChP cells. This suggests the potential of CAF to suppress neuroinflammatory processes induced by peripheral immune/inflammatory challenges. 相似文献
997.
Alejandro Peralta-Garcia Mariona Torrens-Fontanals Tomasz Maciej Stepniewski Judith Grau-Expsito David Perea Vikram Ayinampudi Maria Waldhoer Mirjam Zimmermann María J. Buzn Meritxell Genesc Jana Selent 《International journal of molecular sciences》2021,22(24)
Since the start of the COVID-19 outbreak, pharmaceutical companies and research groups have focused on the development of vaccines and antiviral drugs against SARS-CoV-2. Here, we apply a drug repurposing strategy to identify drug candidates that are able to block the entrance of the virus into human cells. By combining virtual screening with in vitro pseudovirus assays and antiviral assays in Human Lung Tissue (HLT) cells, we identify entrectinib as a potential antiviral drug. 相似文献
998.
Mechanism of the odor-adsorption effect of zinc ricinoleate. A molecular dynamics computer simulation 总被引:1,自引:0,他引:1
Zinc ricinoleate [Zn(Ri)2] is widely used in surfactant and detergent mixtures for the adsorption of odor-active compounds. The mechanism of this process
is not known. In this initial study, we discuss the results of molecular dynamics computer simulations that were performed
to get more information and detailed insights into the interaction mechanism between Zn(Ri)2 and odor-active substances. The calculations, based on simple molecular mechanics approximations, simulated the dynamic features
of the molecular structures of Zn(Ri)2 in vacuum, in the oil phase, and in aqueous solution. We determined actual molecular conformations and simulated an adduct
of ammonia with Zn(Ri)2. On close inspection, in the vacuum and oil phase structures, the Zn2+ ion is almost completely shielded by the oxygen ligands. Calculated structural transitions caused by the interaction of Zn(Ri)2 with water-solvent molecules resulted in a weakening of the electrostatic shield. Nucleophilic attack of odor-active compounds
to the relatively unprotected Zn2+ atom is easy to achieve in aqueous solution. Simulation of the addition product of Zn(Ri)2 with ammonia revealed an elementary structural change, resulting in an increase of the solubility and adsorption activity
of Zn(Ri)2. Molecular dynamics simulations showed that the results coincide with experimental observations. 相似文献
999.
Native maize starches containing amylose are used for manufacturing gels in food technology at concentrations of about 7%. Depending on the pasting conditions chosen, several hours may be required for the final consistency to be attained. For this reason the influence of hydrocolloids was investigated with economic factors dictating an effective concentration of approximately 5% in terms of the pure starch. The gelation process was monitored quantitatively by means of rheomechanical oscillation measurements in the linear viscoelastic range. The substances investigated were polysaccharides with chemically similar structures and classified as safe under foodstuff regulations: guar gum, locust bean gum, x-carrageenan, t-carrageenan, xanthan and carboxymethylcellulose (CMC). The gelation process can be significantly accelerated by a range of hydrocolloids, with the effect decreasing as follows: CMC > locust bean gum > guar gum > x-carrageenan > xanthan. The mixtures achieved between 45% and 80% of the final gelation stability of pure starch of 100Pa. The gelation process is clearly retarded by the hydrocolloid t-carrageenan. With the aid of the rheological data it is possible to correlate the influence of the hydrocolloids on the process of self-aggregation and also on the resulting viscoelastic properties of the mixed gels with one another. In terms of a molecular interpretation it is possible to distinguish between exclusion effects and specific interactions in the functioning of the hydrocolloids. 相似文献
1000.
The paper addresses the question of whether the number of particles in a noncemented granular assembly will affect the mechanical characteristics of the assembly: its strength and stiffness. The question is answered by applying the discrete element method to assemblies of different sizes. To isolate the effect of assembly size, apart from the scatter that usually accompanies such simulations, multiple assemblies were tested. The two-dimensional assemblies had nearly identical initial porosities and fabrics, and they were all loaded in biaxial compression. Two different boundaries were tested: periodic and wall boundaries. We find that the peak compressive strength decreases with assembly size for both types of boundaries and over a range of assembly sizes that contain 256 particles to over 66,000 particles. Stiffness is only slightly reduced and only with wall boundaries. Deformation is less uniform in the larger assemblies, with deformation concentrated in a smaller fraction of the assembly area. An analysis of deformation patterning shows that at least a few thousand particles are required for realistic microband patterning. 相似文献