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11.
Marta Gowacka Sara Lipka Ewelina Mynarska Beata Franczyk Jacek Rysz 《International journal of molecular sciences》2021,22(15)
COVID-19 is mainly considered a respiratory illness, but since SARS-CoV-2 uses the angiotensin converting enzyme 2 receptor (ACE2) to enter human cells, the kidney is also a target of the viral infection. Acute kidney injury (AKI) is the most alarming condition in COVID-19 patients. Recent studies have confirmed the direct entry of SARS-CoV-2 into the renal cells, namely podocytes and proximal tubular cells, but this is not the only pathomechanism of kidney damage. Hypovolemia, cytokine storm and collapsing glomerulopathy also play an important role. An increasing number of papers suggest a strong association between AKI development and higher mortality in COVID-19 patients, hence our interest in the matter. Although knowledge about the role of kidneys in SARS-CoV-2 infection is changing dynamically and is yet to be fully investigated, we present an insight into the possible pathomechanisms of AKI in COVID-19, its clinical features, risk factors, impact on hospitalization and possible ways for its management via renal replacement therapy. 相似文献
12.
Beata Butruk Maciej Trzaskowski Tomasz Ciach 《Materials science & engineering. C, Materials for biological applications》2012,32(6):1601-1609
In this paper the authors present a simple method of coating polyurethane (PU) surface with poly(vinyl pirrolidone) (PVP) hydrogel. The hydrogel-coated materials were designed for use in biomedical applications, especially in blood-contacting devices. The coating is formed due to free radical macromolecular grafting–crosslinking. Polymer surface was first immersed in an organic solution containing radical source: cumene hydroperoxide (CHP) with an addition of a branching and anchoring agent: ethylene glycol dimethylacrylate (EGDMA). In the second step, the substrate was immersed in a water solution containing given concentration of PVP and Fe2+. The novelty of the process consists in the fact that free radicals are formed mostly at the polymer/solution interface, what assures high grafting efficiency together with the formation of covalent bonds between polymer substrate and modifying layer.The process was optimized for reagents concentrations. The coating properties: thickness and the swelling ratio were strongly influenced by CHP, Fe2+, PVP and EGMDA concentrations. The chemical composition of the surface analyzed with FTIR-ATR spectroscopy confirmed the presence of PVP coating. In vitro biocompatibility tests with L929 fibroblasts confirmed non-cytotoxicity of the coatings. Hydrogel coating significantly improved polyurethane hemocompatibility. Studies with human whole blood revealed that both, the platelet consumption and the level of platelet activation were as low as for negative control. 相似文献
13.
Beata Zielińska 《Bulletin of Materials Science》2014,37(4):911-916
In this contribiution LiNbO3 and Ag-loaded LiNbO3 photocatalysts were tested in the reaction of hydrogen evolution. The silver modified samples contained different loading of co-catalyst in the range of 0.5–4 wt%. It was essential to optimize the sample composition to achieve an efficient hydrogen evolution. The optimal sample contained 2 wt% of silver. The detailed analysis indicated that silver was deposited on the surface of LiNbO3 in the form of Ag2O. Therefore, it is supposed that Ag2O was responsible for the enhanced photocatalytic activity in the studied reaction. The crystallographic phases and optical and vibronic properties were examined by X-ray diffraction (XRD) and diffuse reflectance (DR) UV-Vis and resonance Raman spectroscopic methods, respectively. Morphology of the produced samples were studied using a high-resolution transmission electron microscope (HRTEM). 相似文献
14.
Acrylic bone cements modified with poly(ethylene glycol)‐based biocompatible phase‐change materials 下载免费PDF全文
The high polymerization temperature of acrylic bone cements used in hip replacement implantation may cause thermal necrosis of surrounding tissues. In order to reduce the polymerization temperature, acrylic bone cement has been modified with a biocompatible polymeric phase‐change material (PCM) based on poly(ethylene glycol) (PEG) of different molecular weights and stabilized with potato starch. Structural and morphological studies were performed, and the thermal and mechanical properties were investigated. The incorporation of PEG‐based PCM led to a decrease in the polymerization temperature of bone cement from 70 °C for unmodified cement to 58 °C for modified cement. Modified cement materials were stable in incubation tests, although acoustic analysis data revealed a decrease in propagation speed after incubation, which indicates formation of material defects (pores, cracks, voids, etc.) due to water activity. However, in the regeneration process, these defects can be filled by freshly grown bone tissue leading to better incorporation of bone cement replacements into tissue. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43898. 相似文献
15.
Herpes simplex virus types 1 and 2 HSV1 and 2, namely varicella-zoster VZV and cytomegalovirus CMV, are among the most common pathogens worldwide. They remain in the host body for life. The course of infection with these viruses is often asymptomatic or mild and self-limiting, but in immunocompromised patients, such as solid organ or bone marrow transplant recipients, the course can be very severe or even life-threatening. Unfortunately, in the latter group, the highest percentage of infections with strains resistant to routinely used drugs is observed. On the other hand, frequent recurrences of genital herpes can be a problem even in people with normal immunity. Genital herpes also increases the risk of acquiring sexually transmitted diseases, including HIV infection and, if present in pregnant women, poses a risk to the fetus and newborn. Even more frequently than herpes simplex, congenital infections can be caused by cytomegalovirus. We present the most important anti-herpesviral agents, the mechanisms of resistance to these drugs, and the associated mutations in the viral genome. Special emphasis was placed on newly introduced drugs such as maribavir and brincidofovir. We also briefly discuss the most promising substances in preclinical testing as well as immunotherapy options and vaccines currently in use and under investigation. 相似文献
16.
Kamil Cebulski Katarzyna Nowiska Karolina Jabloska Hanna Romanowicz Beata Smolarz Piotr Dzigiel Marzenna Podhorska-Okow 《International journal of molecular sciences》2022,23(7)
Irisin is a myokine formed from fibronectin type III domain-containing protein 5 (FNDC5), which can be found in various cancer tissues. FNDC5 and irisin levels have been poorly studied in the tumor tissues of breast cancer (BC). The aim of this study was to determine the levels of irisin expression in BC tissues and compare them to clinicopathological factors and Ki-67 and PGC-1α expression levels. Tissue microarrays (TMAs) with 541 BC tissues and 61 samples of non-malignant breast disease (NMBD; control) were used to perform immunohistochemical reactions. FNDC5 gene expression was measured in 40 BC tissue samples, 40 samples from the cancer margin, and 16 NMBD samples. RT-PCR was performed for the detection of FNDC5 gene expression. Higher irisin expression was found in BC patients compared to normal breast tissue. FNDC5/irisin expression was higher in patients without lymph node metastases. Longer overall survival was observed in patients with higher irisin expression levels. FNDC5/irisin expression was increased in BC tissues and its high level was a good prognostic factor for survival in BC patients. 相似文献
17.
Urszula Wjcik-Bojek Barbara Ralska Beata Sadowska 《International journal of molecular sciences》2022,23(2)
The main purpose of this review is to present justification for the urgent need to implement specific prophylaxis of invasive Staphylococcus aureus infections. We emphasize the difficulties in achieving this goal due to numerous S. aureus virulence factors important for the process of infection and the remarkable ability of these bacteria to avoid host defense mechanisms. We precede these considerations with a brief overview of the global necessitiy to intensify the use of vaccines against other pathogens as well, particularly in light of an impasse in antibiotic therapy. Finally, we point out global trends in research into modern technologies used in the field of molecular microbiology to develop new vaccines. We focus on the vaccines designed to fight the infections caused by S. aureus, which are often resistant to the majority of available therapeutic options. 相似文献
18.
Ewa Witkowska Magda Godlewska Jowita Osiejuk Sandra Gtarz Beata Wileska Katarzyna Kosiska Joanna Starnowska-Sok Anna Piotrowska Piotr F. J. Lipiski Joanna Mataliska Jolanta Dyniewicz Pawe K. Halik Ewa Gniazdowska Barbara Przewlocka Aleksandra Misicka 《International journal of molecular sciences》2022,23(2)
Based on the mechanism of neuropathic pain induction, a new type of bifunctional hybrid peptidomimetics was obtained for potential use in this type of pain. Hybrids consist of two types of pharmacophores that are connected by different types of linkers. The first pharmacophore is an opioid agonist, and the second pharmacophore is an antagonist of the pronociceptive system, i.e., an antagonist of the melanocortin-4 receptor. The results of tests in acute and neuropathic pain models of the obtained compounds have shown that the type of linker used to connect pharmacophores had an effect on antinociceptive activity. Peptidomimetics containing longer flexible linkers were very effective at low doses in the neuropathic pain model. To elucidate the effect of linker lengths, two hybrids showing very high activity and two hybrids with lower activity were further tested for affinity for opioid (mu, delta) and melanocortin-4 receptors. Their complexes with the target receptors were also studied by molecular modelling. Our results do not show a simple relationship between linker length and affinity for particular receptor types but suggest that activity in neuropathic pain is related to a proper balance of receptor affinity rather than maximum binding to any or all of the target receptors. 相似文献
19.
Mechanism of MxOy nanoparticles/CNTs for catalytic carbonization of polyethylene and application to flame retardancy 下载免费PDF全文
Karolina Wenelska Xuecheng Chen Beata Zielinska Ryszard J. Kaleńczuk Paul K. Chu Tao Tang Ewa Mijowska 《应用聚合物科学杂志》2017,134(34)
Three kinds of metal oxide nanoparticles (Fe3O4, Co3O4, and Ni2O3) are produced on carbon nanotubes (CNTs). The synergistic effects rendered by the CNTs and metal oxide nanoparticles on carbonization of polyethylene (PE) are studied and applications to flame retardancy of PE are investigated systematically. The CNT‐Ni2O3 delivers the best performance and the mechanism pertaining to the enhanced flame retardancy is proposed and discussed. It is found that under the same conditions, the carbonization rate can be a factor to influence the flame retardancy performance. Among Fe, Co, and Ni, Ni has the fastest carbonation rate, which leads to the best flame retardancy performance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45233. 相似文献
20.
Beata Tryba Antoni W. Morawski Michio Inagaki Masahiro Toyoda 《Applied catalysis. B, Environmental》2006,63(3-4):215-221
H2O2 used in the photo-Fenton reaction with iron catalyst can accelerate the oxidation of Fe2+ to Fe3+ under UV irradiation and in the dark (in the so called dark Fenton process). It was proved that conversion of phenol under UV irradiation in the presence of H2O2 predominantly produces highly hydrophilic products and catechol, which can accelerate the rate of phenol decomposition. However, while H2O2 under UV irradiation could decompose phenol to highly hydrophilic products and dihydroxybenzenes in a very short time, complete mineralization proceeded rather slowly. When H2O2 is used for phenol decomposition in the presence of TiO2 and Fe–TiO2, decrease of OH radicals formed on the surface of TiO2 and Fe–TiO2 has been observed and photodecomposition of phenol is slowed down. In case of phenol decomposition under UV irradiation on Fe–C–TiO2 photocatalyst in the presence of H2O2, marked acceleration of the decomposition rate is observed due to the photo-Fenton reactions: Fe2+ is likely oxidized to Fe3+, which is then efficiently recycled to Fe2+ by the intermediate products formed during phenol decomposition, such as hydroquinone (HQ) and catechol. 相似文献