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ABSTRACT

Two sugar-based emulsifiers, cetearyl alcohol & cetearyl glycoside and sorbitan stearate & sucrose cocoate, known as potential promoters of lamellar liquid crystals/gel phases, were investigated in order to formulate an optimal vehicle for amphiphilic drug—diclofenac diethylamine (DDA).

Physico-chemical characterization and study of vehicle's physical stability were performed. Then, the in vitro DDA liberation profile, dependent on the mode of drug incorporation to the system, and the in vivo, short-term effects of chosen samples on skin parameters were examined.

Droplets size distribution and rheological behavior indicated satisfying physical stability of both types of vehicles. Unexpectedly, the manner of DDA incorporation to the system had no significant influence on DDA release. In vivo study pointed to emulsion's favorable potential for skin hydration and barrier improvement, particularly in cetearyl glycoside-based vehicle.  相似文献   
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There is inadequate published data referring to bioactivity of lemon balm tea and its Kombucha. The aim of this study, therefore, was to investigate antimicrobial, antiproliferative, genotoxic, and antigenotoxic potential of lemon balm tea and its Kombucha with consuming acidity. Antimicrobial activity was determined by agar-well diffusion method. Cell growth effects were determined in HeLa, MCF7, and HT-29 human tumor cell lines. Genotoxic and antigenotoxic effects were determined using chromosome aberration assay in Chinese hamster cell line CHO-K1. Differences between control and treated groups were evaluated using analysis of variance, at significance level of p < 0.05. Kombucha from lemon balm tea (Melissa officinalis L.) exibited antimicrobial activity against prokaryotic microorganisms independently of their cell wall structure (both Gram-positive and Gram-negative bacteria), while there was no observed activity against eukaryots (yeasts and moulds). There was absence of genotoxic effects while antigenotoxic effects of lemon balm Kombucha and tea were confirmed on MMC-damaged CHO-K1 cells. For the explanation of cell growth effects that were not concentration dependent, concept of hormesis was used. Antiproliferative activity was lower compared with traditional Kombucha and Satureja montana L. Kombucha, with lemon balm tea showing higher activity than its Kombucha.  相似文献   
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Experimental results on processing, structural and mechanical characterization of a multilayer composite based on commercially pure aluminum foils were presented. A multilayer composite was produced by hot-rolling of anodized and non-anodized aluminum foils alternately sandwiched. In addition, the same process was applied for bonding of non-anodized foils. In both cases, obtained multilayer composites were compact and sound. In order to study composites microstructural evolution and mechanical properties, optical and scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD) analysis, hardness, tensile and three-point flexural tests were performed. Microstructural characterization confirmed that the rod-like particles distributed in parallel rows in the composite aluminum matrix with anodized foils correspond to Al2O3. Maximum and minimum peaks of oxygen and aluminum, respectively, suggest that after the final hot-rolling of composite with non-anodized foils, a small amount of coarser particles were formed at boundaries between foils. Hardness, strength, modulus of elasticity and flexural strength of both multilayer composites were much higher than those of pure aluminum, whereas ductility was significantly less. The composite with anodized foils exhibited the highest strength and modulus of elasticity, but lower ductility compared to composite processed from non-anodized foils. Fracture failure corresponded to the change of ductility.  相似文献   
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With the ever-growing concern for human health and wellbeing, the prenatal period of development requires special attention since fetuses can be exposed to various metals through the mother. Therefore, this study explored the status of selected toxic (Pb, Cd, Ni, As, Pt, Ce, Rb, Sr, U) and essential trace metals (Mn, Co, Cu, Zn, Se) in the umbilical cord (UC) sera, maternal sera, and placental tissue samples of 92 healthy women with normal pregnancies. A further aim focuses on the potential transplacental transfer of these trace metals. Based on the obtained levels of investigated elements in clinical samples, it was observed that all of the trace metals cross the placental barrier and reach the fetus. Furthermore, statistical analysis revealed significant differences in levels of toxic Ni, As, Cd, U, Sr, Rb, and essential Mn, Cu, and Zn between all three types of analyzed clinical samples. Correlation analysis highlighted As to be an element with levels that differed significantly between all tested samples. Principal component analysis (PCA) was used to enhance these findings. PCA demonstrated that Cd, Mn, Zn, Rb, Ce, U, and Sr were the most influential trace metals in distinguishing placenta from maternal and UC serum samples. As, Co, and Cu were responsible for the clustering of maternal serum samples, and PCA demonstrated that the Pt level in UC sera was responsible for the clustering of these samples. Overall, the findings of this study could contribute to a better understanding of transplacental transfer of these trace metals, and shed a light on overall levels of metal exposure in the population of healthy pregnant women and their fetuses.  相似文献   
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The chemical element selenium (Se) is a nonmetal that is in trace amounts indispensable for normal cellular functioning. During pregnancy, a low Se status can increase the risk of oxidative stress. However, elevated concentrations of Se in the body can also cause oxidative stress. This study aimed to compare the effects of BSA-stabilized Se nanoparticles (SeNPs, Se0) (BSA-bovine serum albumin) and inorganic sodium selenite (NaSe, Se+4) supplementation on the histological structure of the placenta, oxidative stress parameters and the total placental Se concentration of Wistar rats during pregnancy. Pregnant females were randomized into four groups: (i) intact controls; (ii) controls that were dosed by daily oral gavage with 8.6% bovine serum albumin (BSA) and 0.125 M vit C; (iii) the SeNP group that was administered 0.5 mg of SeNPs stabilized with 8.6% BSA and 0.125 M vit C/kg bw/day by oral gavage dosing; (iv) the NaSe group, gavage dosed with 0.5 mg Na2SeO3/kg bw/day. The treatment of pregnant females started on gestational day one, lasted until day 20, and on day 21 of gestation, the fetuses with the placenta were removed from the uterus. Our findings show that the mode of action of equivalent concentrations of Se in SeNPs and NaSe depended on its redox state and chemical structure. Administration of SeNPs (Se0) increased fetal lethality and induced changes in the antioxidative defense parameters in the placenta. The accumulation of Se in the placenta was highest in SeNP-treated animals. All obtained data indicate an increased bioavailability of Se in its organic nano form and Se0 redox state in comparison to its inorganic sodium selenite form and Se+4 redox state.  相似文献   
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Surface doping of oxide nanoparticles is important in fields ranging from heterogeneous catalysis to optoelectronics. Here, we report the solvent-free synthesis of mixed calcium-magnesium oxide nanocrystals in the size range between 5 and 40 nm. Although CaMgO mixtures are thermodynamically forbidden on a macroscopic scale, Calcium ions can be distributed homogeneously in MgO using chemical vapor deposition (CVD) as a nonequilibrium technique. Subsequent thermal activation leads to calcium ion segregation into the nanocrystal surface which, in addition to the synthesis parameters, provides efficient means for manipulating the optical surface properties of insulating oxide nanocrystals. A novel material with unexpected photonic behavior, such as enhanced photoluminescence emission which is also red-shifted with respect to those of CaO and MgO, was found.  相似文献   
30.
The challenge raised by the introduction of Internet of Things (IoT) concept will permanently shape the networking and communications landscape and will therefore have a significant social impact. The ongoing IoT research activities are directed towards the definition and design of open architectures and standards, but there are still many issues requiring a global consensus before the final deployment. The paper presents and discusses the IoT architectural frameworks proposed under the ongoing standardization efforts, design issues in terms of IoT hardware and software components, as well as the IoT application domain representatives, such as smart cities, healthcare, agriculture, and nano-scale applications (addressed within the concept of Internet of Nano-Things). In order to obtain the performances related to recently proposed protocols for emerging Industrial Internet of Things applications, the preliminary results for Message Queuing Telemetry Transport and Time-Slotted Channel Hopping protocols are provided. The testing was performed on OpenMote hardware platform and two IoT operating systems: Contiki and OpenWSN.  相似文献   
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