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61.
Magdalena Bielawska Bronisław Jańczuk Anna Zdziennicka 《Journal of surfactants and detergents》2013,16(2):203-212
The surface tension measurements of aqueous solutions of p‐(1,1,3,3‐tetramethylbutyl)phenoxypoly(9.5)ethylene glycol or tert‐octylphenol ethoxylate (TOP10) and cetyltrimethylammonium bromide (CTAB) mixtures with ethanol were carried out in the range of the total concentration of CTAB and TOP10 mixtures from 1 × 10?7 to 1 × 10?2 M and ethanol from 0 to 17.13 M. In the CTAB and TOP10 mixtures, the mole fractions of TOP10 were equal to 0.2; 0.4; 0.6; and 0.8, respectively. The results obtained were compared to those calculated from the Fainerman and Miller equation developed for ideal mixtures of two homologous surfactants, as well as from the Connors equation derived for the concentrated organic solutions. The calculations of the surface tension from the Fainerman and Miller equation were carried out treating the solvent and solute in a few different ways. The differences between the measured and calculated values of the surface tension were discussed in the light of molecular interaction parameter and the composition of the surface layer. The composition of the mixed surface layer at the solution‐air interface was evaluated according to Rosen using the nonideal solution theory with the assumption that water with ethanol is a mixed solvent. Knowing the values of mole fractions of CTAB and TOP10 in the surface layer, the molecular interaction parameter was determined. 相似文献
62.
Magdalena Druszczyska Magdalena Godkowicz Jakub Kulesza Sebastian Wawrocki Marek Fol 《International journal of molecular sciences》2022,23(3)
Cytokine receptors are critical regulators of the antimycobacterial immune response, playing a key role in initiating and coordinating the recruitment and activation of immune cells during infection. They recognize and bind specific cytokines and are involved in inducing intracellular signal transduction pathways that regulate a diverse range of biological functions, including proliferation, differentiation, metabolism and cell growth. Due to mutations in cytokine receptor genes, defective signaling may contribute to increased susceptibility to mycobacteria, allowing the pathogens to avoid killing and immune surveillance. This paper provides an overview of cytokine receptors important for the innate and adaptive immune responses against mycobacteria and discusses the implications of receptor gene defects for the course of mycobacterial infection. 相似文献
63.
Physicochemical quality and oxidative stability of linseed (Linum usitatissimum) and camelina (Camelina sativa) cold‐pressed oils from retail outlets 下载免费PDF全文
64.
Dagmara Wojcik-Grzybek Magdalena Hubalewska-Mazgaj Marcin Surmiak Zbigniew Sliwowski Anna Dobrut Agata Mlodzinska Adrianna Wojcik Slawomir Kwiecien Marcin Magierowski Agnieszka Mazur-Bialy Jan Bilski Tomasz Brzozowski 《International journal of molecular sciences》2022,23(6)
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
65.
Agnieszka Michalak Magdalena Nowosielska Wojciech K. Jóźwiak 《Topics in Catalysis》2009,52(8):1044-1050
The promotion of Fischer-Tropsch catalysts 10%Co/Al2O3, 10%Co/SiO2, 10%Co/TiO2 by 0.5% Ru and the modification of supports by 8.5 wt% ZrO2 have been studied. The following properties: catalyst specific surface area as well as reducibility and dispersion of metallic
phase were studied by different techniques: BET, TPR, and H2 chemisorption. The modification of supports by non-reducible ZrO2, results in a decrease of cobalt oxide reduction on Al2O3 and TiO2 but not on SiO2 supports. Additionally the enhancement of cobalt dispersion was found for all catalysts with ZrO2 modified supports. The impact of Ru promotion is likely due to the stabilization of applied supports, prevention or blockage
of interaction between surface Co species and support and an increase in cobalt oxide reducibility to the catalytically active
metallic cobalt phase. 相似文献
66.
Ryszard Amarowicz Zofia Żegarska Ryszard Rafałowski Ronald B. Pegg Magdalena Karamać Agnieszka Kosińska 《European Journal of Lipid Science and Technology》2009,111(11):1111-1117
Phenolic compounds were extracted from thyme (Thymus vulgaris L.), oregano (Origanum vulgare L.) and marjoram (Origanum majorana L.) with 95% ethanol. A number of antioxidant and radical‐scavenging capacity tests were performed on the prepared extracts using colorimetric assays and model system studies. Specifically, these included determining the content of total phenolics, antioxidant efficacy in a linoleic acid‐ferric thiocyanate model system, reducing power, scavenging effect on 2,2'‐diphenyl‐1‐picrylhydrazyl radical, and hydroxyl radical‐scavenging activity by electron paramagnetic resonance spectroscopy. Moreover, the efficacies of the prepared herb extracts were investigated in a real‐life food product: the stabilization of butter against oxidation. 相似文献
67.
Magdalena Karamać 《European Journal of Lipid Science and Technology》2009,111(11):1063-1071
Tannin fractions were isolated from crude acetonic extracts of defatted walnut, hazelnut and almond kernels using Sephadex LH‐20 column chromatography. The obtained material was characterized by content of total phenolics and electrophoretic separations using capillary zone electrophoresis (CZE). The antioxidant activities of the tannin fractions were analyzed by several methods: DPPH and ABTS assays, photochemiluminescence (PCL) method, as well as in two lipid model systems: emulsion with β‐carotene‐linoleic acid and L ‐α‐lecithin liposomes. The contents of total phenolics in the tannin fractions of walnuts, hazelnuts and almonds were 550, 329 and 83 mg catechin eq/g, respectively. The electrophoretic profiles of hazelnut and almond tannin fractions were similar, in contrast to the walnut profile. All analyzed fractions exhibited strong antioxidant properties. The antioxidant capacity of lipid‐soluble (ACL) compounds determined by PCL method was the highest for the fraction isolated from walnuts – 7.35 mmol Trolox eq/g. The DPPH radical and the ABTS radical cation were scavenged by the walnut tannin fraction with a higher efficacy than by the two other fractions. EC50 values of the DPPH method were 1.8 times higher for the hazelnut fraction and 2.3 times higher for the almond fraction when compared to the walnut tannins. In turn, the total antioxidant activity values were 8.17, 2.82 and 1.98 mmol Trolox eq/g for the walnut, hazelnut and almond fractions, respectively. On the other hand, in both lipid models applied, lower antioxidant activity of walnut tannins than of hazelnut tannins was noted. The antioxidant effect of almond tannins was weaker or similar than that of walnut tannins in the β‐carotene‐linoleic acid emulsion and the L ‐α‐lecithin liposomal system, respectively. 相似文献
68.
Fatty Acid, Tocopherol and Sterol Compositions of Canadian Prairie Fruit Seed Lipids 总被引:1,自引:1,他引:1
Farooq Anwar Roman Przybylski Magdalena Rudzinska Eliza Gruczynska John Bain 《Journal of the American Oil Chemists' Society》2008,85(10):953-959
The seeds of four prairie fruits—chokecherry (Prunus virginiana), thorny buffaloberry (Shepherdia argentea), Woods’ rose (Rosa woodsii) and hawthorn (Crataegus × mordenensis)—from Southern Alberta were investigated. The lipid contents of the seeds were found to be 10.4, 11.5, 3.7 and 3.4%, respectively.
The tested seed lipids contained mainly linoleic acid in the range from 27.9 to 65.6% and oleic acid from 19.7 to 61.9%. The
thorny buffaloberry and Woods’ rose seed lipids contained 29.2 and 30.8% of linolenic acid, respectively. The contents of
palmitic and stearic acids ranged from 3.2 to 5.4% and 1.6 to 2.2%, respectively. The contents of total tocopherols in the
chokecherry, thorny buffaloberry, Woods’ rose and hawthorn seed lipids accounted for 595, 897, 2,358 and 2,837 mg/kg, respectively.
The main sterols in the lipids were β-sitosterol, Δ5-avenasterol, cycloartenol, campesterol, stigmasterol and gramisterol. The results of the present study show that the lipids
from the seeds of the investigated prairie fruits could be a good source of valuable essential fatty acids, tocopherols and
sterols, thus suggesting their application as functional foods and nutraceuticals. 相似文献
69.
70.
Renata Gruszka Krzysztof Zakrzewski Pawe Piotr Liberski Magdalena Zakrzewska 《International journal of molecular sciences》2021,22(2)
Numerous molecular factors disrupt the correctness of the cell cycle process leading to the development of cancer due to increased cell proliferation. Among known causative factors of such process is abnormal gene expression. Nowadays in the light of current knowledge such alterations are frequently considered in the context of mRNA–miRNA correlation. One of the molecular factors with potential value in tumorigenesis is the feedback loop between MYC and E2F genes in which miR-17-5p and miR-20a from the miR-17-92 cluster are involved. The current literature shows that overexpression of the members of the OncomiR-1 are involved in the development of many solid tumors. In the present work, we investigated the expression of components of the MYC/E2F/miR-17-92 network and their closely related elements including members of MYC and E2F families and miRNAs from two paralogs of miR-17-92: miR-106b-25 and miR-106a-363, in the most common brain tumors of childhood, pilocytic astrocytoma (PA), WHO grade 1; ependymoma (EP), WHO grade 2; and medulloblastoma (MB), WHO grade 4. We showed that the highest gene expression was observed in the MYC family for MYCN and in the E2F family for E2F2. Positive correlation was observed between the gene expression and tumor grade and type, with the highest expression being noted for medulloblastomas, followed by ependymomas, and the lowest for pilocytic astrocytomas. Most members of miR-17-92, miR-106a-363 and miR-106b-25 clusters were upregulated and the highest expression was noted for miR-18a and miR-18b. The rest of the miRNAs, including miR-19a, miR-92a, miR-106a, miR-93, or miR-25 also showed high values. miR-17-5p, miR-20a obtained a high level of expression in medulloblastomas and ependymomas, while close to the control in the pilocytic astrocytoma samples. miRNA expression also depended on tumor grade and histology. 相似文献