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101.
Anna Winiarska-Mieczan Katarzyna Kwiatkowska Małgorzata Kwiecień Ewa Baranowska-Wójcik Grzegorz Wójcik Robert Krusiński 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(6):884-892
The study aimed to analyse the intake of Na with cereal products by the population of Poland. In addition, based on available literature, changes in the content of Na in bread sold in the Polish market from 2009 to 2018 were analysed with regard to Na intake reduction campaigns held in Poland since 2009 popularising information about the adverse effect of sodium on the human cardiovascular system. The results led to the conclusion that the analysed products contained 3.042 ± 3.4 g of Na per 1 kg of fresh product. The content of Na in the analysed products was bread > bread rolls > grains > pasta > rice. Cereal products provide 48.3 % of an adult’s intake of Na, where as much as 48.2 % is covered by bread, with only 0.04 % by grains, 0.04 % by pasta, and 0.01 % by rice. According to information available in reference literature from 2009–2017 the content of Na in baked goods has not been subject to significant modifications. In Poland, with regard to an excessive consumption of Na, efficient strategies must be developed to increase the awareness of consumers and to reduce the use of table salt in the most popular products, and in particular in baked goods. One of the ways to reduce the intake of Na would be consumers’ selection of an adequate range of foodstuffs naturally poor in this element or having its content reduced by means of a suitable technology. This can be a significant component of practices preventing the development of hypertension. However, the fact that information about the content of Na in cereal products is often missing from product labels makes consumer choice difficult. 相似文献
102.
Paulina Cholewinska Marta Michalak Deta Łuczycka Katarzyna Czyż 《Journal of Natural Fibers》2020,17(3):382-388
ABSTRACTThe phenomenon of impedance finds an application in many areas of science; however, no studies relate to wool. Thus, the aim of the study was an examination of an effect of from the presence of suint layer on sheep wool fibers on impedance and heat resistance values. Electrical characteristics (impedance [Ω]) and heat resistance were compared in terms of wool washing effect. The impedance of wool samples was tested in the frequency range of 10 Hz to 1 MHz. In order to measure electrical characteristics and heat resistance values, five samples of greasy wool were collected from different sheep breeds, standardized by weight. After the analyses, the samples were washed and reexamined. The results showed significant differences in the impedance between the greasy and washed wool samples in each of the tested breed (p > 0.05). The suint layer reduces the impedance level, which was also confirmed by a heat resistance test results demonstrating that absence of suint layer on wool fibers significantly reduced this feature value (p > 0.05). This was also reflected in the weight differences between the examined wool samples before and after their washing. 相似文献
103.
Bisera Jurišić Dukovski Lea Mrak Katarzyna Winnicka Marta Szekalska Marina Juretić Jelena Filipović-Grčić 《Drying Technology》2013,31(15):1915-1925
AbstractIn this study, we present the development of an innovative dry powder dexamethasone (Dex) nasal delivery system comprising Dex-loaded lipid/alginate nanoparticles incorporated within pectin microspheres (Dex/NPs-loaded pectin microspheres; DNM). DNM microspheres were characterized by the mean diameter of 2.76?±?0.10?µm, zeta-potential of –36.2?±?1.1?mV, and drug loading of 3.3?±?0.3%. The morphology study revealed irregular microsphere surface forming external voids. In contact with simulated nasal fluid, DNM microspheres demonstrated desirable property of moderate swelling and ensured stronger mucoadhesion compared with conventional Dex-loaded pectin microspheres. The strategy of Dex incorporation within the lipid/alginate NPs resulted in prolonged Dex release in relation to Dex being directly entrapped within the conventional pectin microspheres. DNM microspheres showed excellent biocompatibility and rendered Dex permeation across the selected epithelial cell model similar to that of Dex solution. In conclusion, balanced biopharmaceutical properties of the proposed nasal Dex delivery system provides the potential for prolonged contact time with nasal mucosa, prolonged therapeutic effect, and improved patient compliance. 相似文献
104.
105.
Sławomir Wybraniec Karolina Starzak Anna Skopińska Maciej Szaleniec Jacek Słupski Katarzyna Mitka Piotr Kowalski Tadeusz Michałowski 《Food science and biotechnology》2013,22(2):353-363
An effect of metal cations on betanin stability was investigated in aqueous and organic-aqueous solutions. The presence of organic solvents (methanol, ethanol, and acetonitrile) affects substantially the pigments decomposition in acidic media induced by metal cations whose degrading action in such media is significantly higher than in aqueous solutions. The influence of Cu2+ on the stability was studied by spectrophotometry in more detailed manner, because of its ability to form complexes with betanin. The possibility of a complex formation between betanin and Ni2+ was also stated at pH 7–8; its relatively high stability in aqueous samples was observed. A presence of numerous products of betanin decomposition was detected in the wavelength range 380–500 nm in spectra obtained for most of metal cations investigated, especially for higher concentrations of the organic solvents. 相似文献
106.
Katarzyna M. Terlikowska Anna M. Witkowska Malgorzata E. Zujko Bozena Dobrzycka Slawomir J. Terlikowski 《International journal of molecular sciences》2014,15(12):21703-21722
Recent findings on the molecular basis of ovarian cancer development and progression create new opportunities to develop anticancer medications that would affect specific metabolic pathways and decrease side systemic toxicity of conventional treatment. Among new possibilities for cancer chemoprevention, much attention is paid to curcumin—A broad-spectrum anticancer polyphenolic derivative extracted from the rhizome of Curcuma longa L. According to ClinicalTrials.gov at present there are no running pilot studies, which could assess possible therapeutic benefits from curcumin supplementation to patients with primary epithelial ovarian cancer. Therefore, the goal of this review was to evaluate potential preclinical properties of curcumin and its new analogues on the basis of in vivo and in vitro ovarian cancer studies. Curcumin and its different formulations have been shown to display multifunctional mechanisms of anticancer activity, not only in platinum-resistant primary epithelial ovarian cancer, but also in multidrug resistant cancer cells/xenografts models. Curcumin administered together with platinum-taxane chemotherapeutics have been reported to demonstrate synergistic effects, sensitize resistant cells to drugs, and decrease their biologically effective doses. An accumulating body of evidence suggests that curcumin, due to its long-term safety and an excellent profile of side effects should be considered as a beneficial support in ovarian cancer treatment strategies, especially in patients with platinum-resistant primary epithelial recurrent ovarian cancer or multidrug resistant disease. Although the prospect of curcumin and its formulations as anticancer agents in ovarian cancer treatment strategy appears to be challenging, and at the same time promising, there is a further need to evaluate its effectiveness in clinical studies. 相似文献
107.
108.
Christina Wildfire Engin Çiftyürek Katarzyna Sabolsky Edward M. Sabolsky 《Journal of Materials Science》2014,49(14):4735-4750
The incorporation of selective nanomaterials, such as common metal oxide semiconductor compositions, into resistive-type gas sensors has been shown by many researchers to lead to very high sensitivities and response rates, especially for micro-sized chemical sensors for room-temperature applications. The same strategy utilizing sensing nanomaterials has not been demonstrated for high-temperature sensors due to the intrinsic instability of typical metal oxide semiconductor nanomaterials at temperatures >500 °C. Within this work, doped Gd2Zr2O7 (GZO) nanomaterial compositions were investigated for H2 resistive-type sensors for applications between 600 and 1000 °C. This paper investigates the mechanism of H2 sensing for doped GZO nanomaterials and SnO2/GZO nanocomposites at the elevated temperatures. By integrating 10 vol.% nano-SnO2 into yttrium-doped GZO nanomaterials, a sensitivity of 4.15 % was retained for 4000 ppm H2 levels with a low signal drift of 0.42 %/h at 1000 °C in a 20 % O2/N2 gas stream. The signal drift was reduced by more than half of that compared to pure nano-SnO2 at the same conditions. The nano-GZO limited the grain growth of the nano-SnO2 particles and also prevented the nano-SnO2 from fully reducing to Sn at high temperatures in a low oxygen atmosphere. It is among the first resistive-type sensors operating at 1000 °C with sensing times of <5 min. This demonstration provided an example of a strategy of combining traditional metal oxide semiconductor and refractory nanomaterial compositions to form sensing nanocomposites with new sensing mechanisms, as well as, enhanced chemical and microstructural stabilities in high-temperature environments. 相似文献
109.
Carminna Ottone Vivian Farías Rivera Marco Fontana Katarzyna Bejtka Barbara Onida Valentina Cauda 《材料科学技术学报》2014,30(12):1167-1173
Highly mesoporous Zn O and g-Al2O3nanowires(NWs) are both synthesized by a hydrothermal method using commercially available porous anodic aluminium oxide(AAO) as template. AAO membrane acts as template for Zn O NWs and both as template and precursor for g-Al2O3 NWs. The formation of intermediate phases of porous Zn6Al2(OH)16CO3and boehmite(g-Al OOH) were observed, both occurring during the hydrothermal synthesis of porous Zn O and g-Al2O3 NWs, respectively, and disappearing after annealing at 600 C. This novel template-assisted hydrothermal process leads to the formation of porous Zn O and g-Al2O3NWs(specific surface area of 192 m2 g 1and 263 m2 g 1, respectively), showing pore sizes around 4 nm in diameter. The influence of the reaction parameters on the nanostructure morphology was also investigated. A Zn O seed layer, deposited on the AAO channels prior to the hydrothermal synthesis, leads to more compact Zn O nanowires(99 m2 g-1) protecting the AAO host from the chemical attack of the precursor solution. 相似文献
110.
Marcin ?roda Katarzyna Cholewa-KowalskaMarek Ró?ański Marek Nocuń 《Optical Materials》2011,33(3):397-401
Glasses of different matrix (phosphate, borate, silicate and lead-silicate) were studied for their optical properties. The effect of Er dopant on transmittance and luminescence properties was presented. The significant “red shift” and “blue shift” of UV edge absorption were discussed based on the changes in the framework of the borate and phosphate glasses, respectively. It was showed that the integral intensity of the two main optical absorption transitions monotonically increases with the order: phosphate < borate < silicate < lead-silicate. Ellipsometric measurement was applied to obtain the refractive index of the glasses. The correlation between the shift of edge absorption and the change of refractive index was presented. Effect of glassy matrix on luminescence of Er3+ was discussed. 相似文献