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61.
Inflammatory bowel diseases (IBD) are commonly considered as Crohn’s disease and ulcerative colitis, but the possibility that the alterations in gut microbiota and oxidative stress may affect the course of experimental colitis in obese physically exercising mice treated with the intestinal alkaline phosphatase (IAP) has been little elucidated. Mice fed a high-fat-diet (HFD) or normal diet (ND) for 14 weeks were randomly assigned to exercise on spinning wheels (SW) for 7 weeks and treated with IAP followed by intrarectal administration of TNBS. The disease activity index (DAI), grip muscle strength test, oxidative stress biomarkers (MDA, SOD, GSH), DNA damage (8-OHdG), the plasma levels of cytokines IL-2, IL-6, IL-10, IL-12p70, IL-17a, TNF-α, MCP-1 and leptin were assessed, and the stool composition of the intestinal microbiota was determined by next generation sequencing (NGS). The TNBS-induced colitis was worsened in obese sedentary mice as manifested by severe colonic damage, an increase in DAI, oxidative stress biomarkers, DNA damage and decreased muscle strength. The longer running distance and weight loss was observed in mice given IAP or subjected to IAP + SW compared to sedentary ones. Less heterogeneous microbial composition was noticed in sedentary obese colitis mice and this effect disappeared in IAP + SW mice. Absence of Alistipes, lower proportion of Turicibacter, Proteobacteria and Faecalibacterium, an increase in Firmicutes and Clostridium, a decrease in oxidative stress biomarkers, 8-OHdG content and proinflammatory cytokines were observed in IAP + SW mice. IAP supplementation in combination with moderate physical activity attenuates the severity of murine colitis complicated by obesity through a mechanism involving the downregulation of the intestinal cytokine/chemokine network and oxidative stress, the modulation of the gut microbiota and an improvement of muscle strength.  相似文献   
62.
The thermal conditions for obtaining the glass-ceramic material of Al0.107B0.374Mg0.043Zn0.282Ca0.100Si0.927O3 with a crystalline phase in the form of gahnite (ZnAl2O4) were specified. The activation energy Ea and the Avrami parameter n for the crystallisation process were determined with the non-isothermal DTA procedure. The maximum temperatures of crystallisation of phases, depending on the rate of heating, ranged between 800-840 °C for willemite and 870-915 °C for gahnite. The homogeneous crystalline spinel phase was obtained by heat treatment above 1000 °C. Precipitation solely of a ghanite phase from glass-ceramic causes a relative increase in its fracture toughness and wear resistance compared to the two-phase materials, i.e., KIC = 2.12-1.65 MPam1/2 and ws = 0.21 × 10−4 mm3/Nm to ws = 1.43 × 10−4 mm3/Nm.  相似文献   
63.
Where do you stop? Three recent publications have described how the oxidation of 5-methylcytosine by Tet dioxygenases does not stop at the 5-hydroxymethylcytosine (5hmC) state, rather further oxidation of 5hmC is involved in DNA demethylation. The nature of the enzymes involved in this process shed light on the dynamics of epigenetic signaling and its evolutionary origin.  相似文献   
64.
ABSTRACT

This study presents the application of fly ash from brown coal and biomass burning power plant as a sorbent for the removal of boron ions from an aqueous solution. The adsorption process efficiency depended on the parameters, such as adsorbent dosage, pH, temperature, agitation time and initial boron concentration. The experimental data fitted well with the Freundlich isotherm model and the maximum capacity was found to be 16.14 mg g?1. The adsorption kinetics followed the pseudo-second-order model. Also, the intra-particle diffusion model parameters were calculated. Thermodynamic parameters such as change in free energy (ΔG°), enthalpy (ΔH°), entropy (ΔS°) revealed on exothermic nature of boron adsorption onto the fly ash.  相似文献   
65.
66.
Numerous studies have confirmed the coexistence of oxidative stress and inflammatory processes. Long-term inflammation and oxidative stress may significantly affect the initiation of the neoplastic transformation process. Here, we describe the synthesis of a new series of Mannich base-type hybrid compounds containing an arylpiperazine residue, 1,3,4-oxadiazole ring, and pyridothiazine-1,1-dioxide core. The synthesis was carried out with the hope that the hybridization of different pharmacophoric molecules would result in a synergistic effect on their anti-inflammatory activity, especially the ability to inhibit cyclooxygenase. The obtained compounds were investigated in terms of their potencies to inhibit cyclooxygenase COX-1 and COX-2 enzymes with the use of the colorimetric inhibitor screening assay. Their antioxidant and cytotoxic effect on normal human dermal fibroblasts (NHDF) was also studied. Strong COX-2 inhibitory activity was observed after the use of TG6 and, especially, TG4. The TG11 compound, as well as reference meloxicam, turned out to be a preferential COX-2 inhibitor. TG12 was, in turn, a non-selective COX inhibitor. A molecular docking study was performed to understand the binding interaction of compounds at the active site of cyclooxygenases.  相似文献   
67.
The importance of coenzyme A (CoA) as a carrier of acyl residues in cell metabolism is well understood. Coenzyme A participates in more than 100 different catabolic and anabolic reactions, including those involved in the metabolism of lipids, carbohydrates, proteins, ethanol, bile acids, and xenobiotics. However, much less is known about the importance of the concentration of this cofactor in various cell compartments and the role of altered CoA concentration in various pathologies. Despite continuous research on these issues, the molecular mechanisms in the regulation of the intracellular level of CoA under pathological conditions are still not well understood. This review summarizes the current knowledge of (a) CoA subcellular concentrations; (b) the roles of CoA synthesis and degradation processes; and (c) protein modification by reversible CoA binding to proteins (CoAlation). Particular attention is paid to (a) the roles of changes in the level of CoA under pathological conditions, such as in neurodegenerative diseases, cancer, myopathies, and infectious diseases; and (b) the beneficial effect of CoA and pantethine (which like CoA is finally converted to Pan and cysteamine), used at pharmacological doses for the treatment of hyperlipidemia.  相似文献   
68.
Deregulated melanogenesis is involved in melanomagenesis and melanoma progression and resistance to therapy. Vitamin D analogs have anti-melanoma activity. While the hypercalcaemic effect of the active form of Vitamin D (1,25(OH)2D3) limits its therapeutic use, novel Vitamin D analogs with a modified side chain demonstrate low calcaemic activity. We therefore examined the effect of secosteroidal analogs, both classic (1,25(OH)2D3 and 25(OH)D3), and novel relatively non-calcemic ones (20(OH)D3, calcipotriol, 21(OH)pD, pD and 20(OH)pL), on proliferation, colony formation in monolayer and soft-agar, and mRNA and protein expression by melanoma cells. Murine B16-F10 and hamster Bomirski Ab cell lines were shown to be effective models to study how melanogenesis affects anti-melanoma treatment. Novel Vitamin D analogs with a short side-chain and lumisterol-like 20(OH)pL efficiently inhibited rodent melanoma growth. Moderate pigmentation sensitized rodent melanoma cells towards Vitamin D analogs, and altered expression of key genes involved in Vitamin D signaling, which was opposite to the effect on heavily pigmented cells. Interestingly, melanogenesis inhibited ligand-induced Vitamin D receptor translocation and ligand-induced expression of VDR and CYP24A1 genes. These findings indicate that melanogenesis can affect the anti-melanoma activity of Vitamin D analogs in a complex manner.  相似文献   
69.
A number of polyphosphazenes with negatively charged β‐alanine (β‐Ala) and γ‐amino butyric acid (GABA) side groups were synthesized and studied for their ability to initiate the growth of hydroxyapatite (HAp) during exposure to simulated body fluid (SBF). All the polymers were hydrolytically sensitive, with the final hydrolysis rate dependent on the specific active side groups (GABA > β‐Ala). These systems also underwent extensive mineralization, with calcium phosphate deposited across their entire surface during exposure to SBF (up to 115 wt % gain after 4 weeks). This degree of deposition is a major advance over previously reported polyphosphazene systems, which underwent a maximum of 27 wt % gain after immersion in SBF for 4 weeks. The extent of mineralization over the surface was monitored using environmental scanning electron microscopy (ESEM) coupled with energy dispersive X‐ray spectroscopy (EDS). In addition, X‐ray diffraction (XRD) was used to determine the identity of the mineralized material. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41741.  相似文献   
70.
Linseed oil, also known as flaxseed oil, is obtained from the dried, ripened seeds of the flax plant (Linum usitatissimum). The oil is obtained by pressing, sometimes followed by solvent extraction supported by a refining process. Linseed oil is an edible oil that is in demand as a nutritional supplement, as a source of α‐linolenic acid an n‐3 fatty acid. The aim of this work was to investigate: (1) the influence of the corn crisp extrusion process on the degradation of fatty acids in linseed oil (LO) and some preparations obtained from the linseed oil such as ethyl ester (EE) and free fatty acids (FFA) added to the corn in order to increase the nutritional value of the crisps, (2) influence of the oil and two fatty preparations obtained from it on the quality of corn crisps, (3) interaction of the lipid fraction with starch. The extrusion process did not degrade the fatty acids significantly. Expansion ratio obtained in the corn crisp extrusion process decreased from 620 % down to 153 %, the size of pores/thickness of the starch–protein walls forming the structure of the extruded product decreased from 10 μm down to 4 μm, the hardness of the crisps increased from 20 to 75 N, and number of lipid–starch complexes increased with rising polarity of the lipid fraction. FFA were complexed mostly by starch (about 90 %), to a lesser degree by EE (about 60 %) and to the least extent by triacylglycerols (about 10 %). The studies performed under industrial conditions using the single screw extruder for the production of corn crisps with the application of standard parameters of the extrusion process indicated that the addition of a mass of 5 % of the various lipids (triacylglycerols of linseed oil, ethyl esters and fatty acids obtained from linseed oil) to corn grits prior to the extrusion process significantly affect the quality of corn crisps.  相似文献   
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