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951.
Marek Pajk Magdalena Wo
niczka Marta E. Lichawska Bartomiej Czerwiski Jakub Wodarczyk Jakub Fichna 《International journal of molecular sciences》2022,23(10)
The present work describes the complexation properties of two oxime-containing Schiff bases (used as ligands), viz. 2-hydroxyimino-N′-[1-(2-pyridyl)ethylidene]propanohydrazone (Hpop) and 2-hydroxyimino-N′-[(pyridine-2-yl)methylidene]propanohydrazone (Hpoa), with Co(II) ions in DMSO/water solution. Volumetric (oxygenation) studies were carried out to determine the uptake of molecular oxygen O2 in the formation of the complexes Co(II)-Hpop and Co(II)-Hpoa. The acquired data can be useful in the development of oxygen bioinorganic complexes of metal ions with Schiff base ligands in solution. Their properties allow them to be used as synthetic oxygen transporters. Moreover, the binding of dioxygen could play an important role in the research of catalytic activity by such systems. 相似文献
952.
Kinga Jaworska Wojciech Kopacz Mateusz Koper Mateusz Szudzik Marta Gawry-Kopczyska Marek Konop Tomasz Hutsch Dawid Chabowski Marcin Ufnal 《International journal of molecular sciences》2022,23(11)
Evidence suggests that microbiota-derived metabolites, including short-chain fatty acids (SCFAs) and trimethylamine-oxide (TMAO), affect the course of diabetic multiorgan pathology. We hypothesized that diabetes activates the intestinal renin–angiotensin system (RAS), contributing to gut pathology. Twelve-week-old male rats were divided into three groups: controls, diabetic (streptozotocin-induced) and diabetic treated with enalapril. Histological examination and RT-qPCR were performed to evaluate morphology and RAS expression in the jejunum and the colon. SCFA and TMAO concentrations in stools, portal and systemic blood were evaluated. In comparison to the controls, the diabetic rats showed hyperplastic changes in jejunal and colonic mucosa, increased plasma SCFA, and slightly increased plasma TMAO. The size of the changes was smaller in enalapril-treated rats. Diabetic rats had a lower expression of Mas receptor (MasR) and angiotensinogen in the jejunum whereas, in the colon, the expression of MasR and renin was greater in diabetic rats. Enalapril-treated rats had a lower expression of MasR in the colon. The expression of AT1a, AT1b, and AT2 receptors was similar between groups. In conclusion, diabetes produces morphological changes in the intestines, increases plasma SCFA, and alters the expression of renin and MasR. These alterations were reduced in enalapril-treated rats. Future studies need to evaluate the clinical significance of intestinal pathology in diabetes. 相似文献
953.
ŠIMURDA David FÜRST Jiří HÁLA Jindřich LUXA Martin BOBČÍK Marek NOVÁK Ondřej SYNÁČJaroslav 《热科学学报(英文版)》2021,30(1):220-230
This paper investigates the flow past two variants of root section profile cascades for a last stage rotor considering three-dimensional flow structures in the near-wall region.Analyses were drawn based on RANS numerical simulations of both variants and on the experimental data obtained by the 3 D traversing in the exit flow field of one of the variants.Extent of 3 D structures at two different regimes and its influence on aerodynamic characteristics of the blade cascades was assessed.The distributions of Mach number along the profiles were compared with 2 D optical measurements and its distortion due to the presence of the sidewall was explored.The interaction between main vortical structures was described and its influence on the loading of the blades,mechanical energy losses and exit flow angle was discussed.The results showed that for a front loaded blade the vortical structures appeared earlier and at a larger extent than for an aft loaded variant.However,due to different Mach number distribution,contribution of end wall flow to the energy losses was lower in the case of the aft loaded variant.The influence of the near wall flow on the loading was found to be rather weak while the deviation of the exit flow angle appeared to be comparable for both of the variants. 相似文献
954.
By intracellular and whole cell recording in rat brain slices, it was found that bath-applied serotonin (5-HT) produces an increase in the frequency and amplitude of spontaneous excitatory postsynaptic potentials/currents (EPSPs/EPSCs) in layer V pyramidal cells of neocortex and transitional cortex (e.g. medial prefrontal, cigulate and frontoparietal). The EPSCs were suppressed by LY293558, an antagonist selective for the AMPA subtype of excitatory amino acid receptor, and by two selective 5-HT2A receptor antagonists, MDL 100907 and SR 46349B. In addition, the EPSCs were suppressed by the fast sodium channel blocker tetrodotoxin (TTX) and were dependent upon external calcium. However, despite being TTX-sensitive and calcium dependent, there was no evidence that the EPSPs resulted from an increase in impulse flow in excitatory neuronal afferents to layer V pyramidal cells. The EPSCs could be induced rapidly by the microiontophoresis of 5-HT directly to "hot spots" within the apical (but not basilar) dendritic field of recorded neurons, indicating that excitatory amino acids may be released by a TTX-sensitive focal action of 5-HT on a subset of glutamatergic terminals in this region. Consistent with such a presynaptic action, the inhibitory metabotropic glutamate receptor agonist (1S,3S)-aminocyclopentane-1,3-dicarboxylate markedly reduced the induction of EPSPs by 5-HT. Postsynaptically, 5-HT enhanced a subthreshold TTX-sensitive sodium current, potentially contributing to an amplification of EPSC amplitudes. These data suggest 5-HT. via 5-HT2A receptors, enhances spontaneous EPSPs/EPSCs in neocortical layer V pyramidal cells through a TTX-sensitive focal action in the apical dendritic field which may involve both pre- and postsynaptic mechanisms. 相似文献
955.
Jana Rudolfov Vladimír Krytof Marek Ne
as Robert Vícha Michal Rouchal 《International journal of molecular sciences》2022,23(23)
Purine nucleosides represent an interesting group of nitrogen heterocycles, showing a wide range of biological effects. In this study, we designed and synthesized a series of 6,9-disubstituted and 2,6,9-trisubstituted purine ribonucleosides via consecutive nucleophilic aromatic substitution, glycosylation, and deprotection of the ribofuranose unit. We prepared eight new purine nucleosides bearing unique adamantylated aromatic amines at position 6. Additionally, the ability of the synthesized purine nucleosides to form stable host–guest complexes with β-cyclodextrin (β-CD) was confirmed using nuclear magnetic resonance (NMR) and mass spectrometry (ESI-MS) experiments. The in vitro antiproliferative activity of purine nucleosides and their equimolar mixtures with β-CD was tested against two types of human tumor cell line. Six adamantane-based purine nucleosides showed an antiproliferative activity in the micromolar range. Moreover, their effect was only slightly suppressed by the presence of β-CD, which was probably due to the competitive binding of the corresponding purine nucleoside inside the β-CD cavity. 相似文献
956.
Anna Wajda Marcela Walczyk Ewa Dudek Barbara Stypiska Aleksandra Lewandowska Katarzyna Romanowska-Prchnicka Marek Chojnowski Marzena Olesiska Agnieszka Paradowska-Gorycka 《International journal of molecular sciences》2022,23(18)
Background and aims: Systemic sclerosis (SSc) is an autoimmune, rare multisystem chronic disease that is still not well-understood aetiologically and is challenging diagnostically. In the literature, there are ever-increasing assumptions regarding the epigenetic mechanisms involved in SSc development; one of them is circulating microRNAs. Many of them regulate TLR pathways and are significant in autoimmune balance. The aim of this study was to determine profile expression of selected microRNAs in SSc patients, including miR-126, -132, -143, -145, -155, -181a, -29a and -3148, in comparison to healthy controls. Methods: Serum microRNAs were isolated from 45 patients with SSc and 57 healthy donors (HC). Additionally, SSc patients were considered in the aspect of disease subtype, including diffuse systemic sclerosis (dcSSc) and limited systemic sclerosis (lcSSc). Results: miR-3148 was detected neither in the serum of HC nor in SSc patients. All of the rest of the analyzed microRNAs, excluding miR-126, miR-29a and miR-181a, were significantly upregulated in SSc patients in comparison to HC. However, miR-181a has been revealed only in the serum of patients with lcSSc but not dcSSc. Moderate positive correlations between the transfer factor of the lung for carbon monoxide (TLCO) and miR-126 and miR-145 were observed. A significant correlation has been found between serum miR-143 level and forced vital capacity (FVC). SSc patients with FVC ≤ 70% were characterized by significantly lower levels of miR-143 compared to patients with normal FVC. Additionally, the expression of miR-132 was significantly higher in dcSSc subgroup with detected active lung lesions compared to dcSSc patients with fibrotic lesions. Patients with an early scleroderma pattern of microangiopathy seen on nailfold video-capillaroscopy (NVC) revealed higher expression of miR-155 in serum than those with a late pattern. Conclusions: The expression profile of circulating cell-free miRNAs is significantly changed in the serum of SSc patients compared to healthy individuals. Downregulation of miRNA-181a and overexpression of miR-132, miR-143, miR-145 and miR-155 in serum may be significant in SSc in the context of biomarkers. 相似文献
957.
Katarzyna Krukiewicz Alicja Kazek-Ksik Monika Brzychczy-Woch Marek J. os Collins Njie Ateba Parvaneh Mehrbod Saeid Ghavami Divine Yufetar Shyntum 《International journal of molecular sciences》2022,23(17)
Biofilms are complex structures formed by bacteria, fungi, or even viruses on biotic and abiotic surfaces, and they can be found in almost any part of the human body. The prevalence of biofilm-associated diseases has increased in recent years, mainly because of the frequent use of indwelling medical devices that create opportunities for clinically important bacteria and fungi to form biofilms either on the device or on the neighboring tissues. As a result of their resistance to antibiotics and host immunity factors, biofilms have been associated with the development or persistence of several clinically important diseases. The inability to completely eradicate biofilms drastically increases the burden of disease on both the patient and the healthcare system. Therefore, it is crucial to develop innovative ways to tackle the growth and development of biofilms. This review focuses on dental- and implant-associated biofilm infections, their prevalence in humans, and potential therapeutic intervention strategies, including the recent advances in pharmacology and biomedical engineering. It lists current strategies used to control the formation of clinically important biofilms, including novel antibiotics and their carriers, antiseptics and disinfectants, small molecule anti-biofilm agents, surface treatment strategies, and nanostructure functionalization, as well as multifunctional coatings particularly suitable for providing antibacterial effects to the surface of implants, to treat either dental- or implant-related bacterial infections. 相似文献
958.
Nadia Sawicka-Gutaj Dawid Gruszczyski Natalia Zawalna Kacper Nijakowski Ilaria Muller Tomasz Karpiski Mario Salvi Marek Ruchaa 《International journal of molecular sciences》2022,23(21)
Autoimmune thyroid diseases (AITDs) are chronic autoimmune disorders that cause impaired immunoregulation, leading to specific immune responses against thyroid antigens. Graves’ disease (GD) and Hashimoto’s thyroiditis (HT) are the major forms of AITDs. Increasing evidence suggests a possible role of microbiota alterations in the pathogenesis and progression of AITDs. This systematic review was designed to address the following question: “Is microbiota altered in patients with AITDs?” After screening the selected studies using the inclusion and exclusion criteria, 16 studies were included in this review (in accordance with PRISMA statement guidelines). A meta-analysis revealed that patients with HT showed significantly higher values of diversity indices (except for the Simpson index) and that patients with GD showed significant tendencies toward lower values of all assessed indices compared with healthy subjects. However, the latter demonstrated a higher relative abundance of Bacteroidetes and Actinobacteria at the phylum level and thus Prevotella and Bifidobacterium at the genus level, respectively. Thyroid peroxidase antibodies showed the most significant positive and negative correlations between bacterial levels and thyroid functional parameters. In conclusion, significant alterations in the diversity and composition of the intestinal microbiota were observed in both GD and HT patients. 相似文献
959.
Lukasz Beca Gang Cheng Geoffrey C. Fox Tomasz Jurga Konrad Olszewski Marek Podgorny Piotr Sokolowski Krzysztof Walczak 《Concurrency and Computation》1997,9(6):521-533
Web technologies – in particular linked Java servers and clients – allow new dynamic collaborative environments linking people and computers. We describe the architecture of a system, TANGOsim, that combines a Java collaborative environment with an executive providing general message filters, and an event-driven simulator. The initial application is to command and control, but we describe how this approach can also be used in other areas, such as health care, scientific visualization and (distance) education. © 1997 John Wiley & Sons, Ltd. 相似文献
960.
Surfactant–latex molecular level interactions as well as transient effects during latex film formation play an important role in latex technology. This review article focuses on the siloxane effects on anionic sodium dioctylsulfosuccinate (SDOSS) surfactant exudation during latex coalescence and quantitative analysis of SDOSS distribution at the both film–air (F–A) and film–substrate (F–S) interfaces. Attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy was utilized for characterization of the interactions between SDOSS and styrene–butyl acrylate latex copolymers. In addition, studies of SDOSS stratification along with depth-profiling analysis during latex film formation utilizing step-scan photoacoustic (S2-PAS) FTIR spectroscopy illustrate that SDOSS content is enriched at the F–A interface and decreases as the penetration depth increases across the latex film thickness. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 1321–1348, 1998 相似文献