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671.
Marta Andres-Mach Aleksandra Szewczyk Mirosaw Zagaja Joanna Szala-Rycaj Marta Kinga Lemieszek Maciej Maj Micha Abram Krzysztof Kaminski 《International journal of molecular sciences》2021,22(6)
Status epilepticus (SE) is a frequent medical emergency that can lead to a variety of neurological disorders, including cognitive impairment and abnormal neurogenesis. The aim of the presented study was the in vitro evaluation of potential neuroprotective properties of a new pyrrolidine-2,5-dione derivatives compound C11, as well as the in vivo assessment of the impact on the neurogenesis and cognitive functions of C11 and levetiracetam (LEV) after pilocarpine (PILO)-induced SE in mice. The in vitro results indicated a protective effect of C11 (500, 1000, and 2500 ng/mL) on astrocytes under trophic stress conditions in the MTT (3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide) test. The results obtained from the in vivo studies, where mice 72 h after PILO SE were treated with C11 (20 mg/kg) and LEV (10 mg/kg), indicated markedly beneficial effects of C11 on the improvement of the neurogenesis compared to the PILO control and PILO LEV mice. Moreover, this beneficial effect was reflected in the Morris Water Maze test evaluating the cognitive functions in mice. The in vitro confirmed protective effect of C11 on astrocytes, as well as the in vivo demonstrated beneficial impact on neurogenesis and cognitive functions, strongly indicate the need for further advanced molecular research on this compound to determine the exact neuroprotective mechanism of action of C11. 相似文献
672.
Aleksandra Kędzierska-Sar Paweł Falkowski Julita Smalc-Koziorowska Stanisław Gierlotka Mikołaj Szafran 《Journal of the European Ceramic Society》2021,41(6):3527-3534
The preparation process and the properties of Al2O3-W nanocomposites obtained by gelcasting are reported. The novelty of the synthesis path is the formation of nano-tungsten particles in an in situ reduction of water-soluble precursor during pressureless sintering. The use of water-soluble salt as a tungsten precursor ensured highly homogenous distribution of reinforcing particles and good adhesion between ceramic and metal phases. The maximum content of tungsten in the composites was approximately 0.5 wt%. The size of the reinforcing particles was less than 100 nm. Presence of metallic tungsten and tungsten carbide (W2C) in the composites lead to the improvement of mechanical parameters: an increase of hardness by about 10 % and of fracture toughness by about 20 %, compared to the reference sample of pure aluminum oxide. 相似文献
673.
Daniil V. Kladko Aleksandra S. Falchevskaya Nikita S. Serov Artur Y. Prilepskii 《International journal of molecular sciences》2021,22(10)
Nanomaterials are proven to affect the biological activity of mammalian and microbial cells profoundly. Despite this fact, only surface chemistry, charge, and area are often linked to these phenomena. Moreover, most attention in this field is directed exclusively at nanomaterial cytotoxicity. At the same time, there is a large body of studies showing the influence of nanomaterials on cellular metabolism, proliferation, differentiation, reprogramming, gene transfer, and many other processes. Furthermore, it has been revealed that in all these cases, the shape of the nanomaterial plays a crucial role. In this paper, the mechanisms of nanomaterials shape control, approaches toward its synthesis, and the influence of nanomaterial shape on various biological activities of mammalian and microbial cells, such as proliferation, differentiation, and metabolism, as well as the prospects of this emerging field, are reviewed. 相似文献
674.
Slavica M. Milić Milan D. Kostić Petar S. Milić Vesna M. Vučić Aleksandra Č. Arsić Vlada B. Veljković Olivera S. Stamenković 《化学工程与技术》2020,43(12):2373-2381
Rosehip (Rosa canina L.) oil (RSO) was recovered from waste rosehip seeds by cold pressing as well as maceration and Soxhlet extraction using n-hexane. The influence of the extraction temperature, the solvent-to-seed ratio (SSR), and the extraction time on RSO yield was examined for the maceration process. The extraction technique did not influence the fatty acid profile of the RSO. All process factors had a significant effect on the oil yield. The kinetics was described using the model involving instantaneous washing followed by diffusion. The RSO maceration was spontaneous, endothermic, and irreversible. 相似文献
675.
Aleksandra Ryk Aleksandra osiewicz Arkadiusz Michalak Wojciech Fendler 《International journal of molecular sciences》2020,21(24)
People with type 1 diabetes have an increased risk of developing microvascular complications, which have a negative impact on the quality of life and reduce life expectancy. Numerous studies in animals with experimental diabetes show that c-peptide supplementation exerts beneficial effects on diabetes-induced damage in peripheral nerves and kidneys. There is substantial evidence that c-peptide counteracts the detrimental changes caused by hyperglycemia at the cellular level, such as decreased activation of endothelial nitric oxide synthase and sodium potassium ATPase, and increase in formation of pro-inflammatory molecules mediated by nuclear factor kappa-light-chain-enhancer of activated B cells: cytokines, chemokines, cell adhesion molecules, vascular endothelial growth factor, and transforming growth factor beta. However, despite positive results from cell and animal studies, no successful c-peptide replacement therapies have been developed so far. Therefore, it is important to improve our understanding of the impact of c-peptide on the pathophysiology of microvascular complications to develop novel c-peptide-based treatments. This article aims to review current knowledge on the impact of c-peptide on diabetic neuro- and nephropathy and to evaluate its potential therapeutic role. 相似文献
676.
Iga Szpunar Sebastian Wachowski Tadeusz Miruszewski Kacper Dzierzgowski Karolina Górnicka Tomasz Klimczuk Magnus Helgerud Sørby María Balaguer José M. Serra Ragnar Strandbakke Maria Gazda Aleksandra Mielewczyk-Gryń 《Journal of the American Ceramic Society》2020,103(3):1809-1818
The cubic Ba0.5La0.5CoO3-δ was synthesized using solid state reaction. The structural properties were determined by the simultaneous refinement of Synchrotron Powder X-ray Diffraction and Neutron Powder Diffraction data. Iodometric titration was used to examine the oxygen stoichiometry and average cobalt oxidation state. Low-temperature magnetic studies show soft ferromagnetic character of fully oxidized material, with θP = 198(3) K and µeff = 2.11(2) µB. Electric measurements show the thermally activated nature of conductivity at low temperatures, whereas, due to the variable oxidation and spin state of cobalt, a single charge transport mechanism cannot be distinguished. Around room temperature, a wide transition from thermally activated conductivity to semi-metallic behavior is observed. Under the inert atmosphere, the oxygen content lowers and the cation ordering takes place, leading to coexistence of two, ordered and disordered, phases. As a result of this change, thermally activated conductivity is observed also at high temperatures in inert atmosphere. 相似文献
677.
678.
Marcin Oarowski Tomasz M. Karpiski Aleksandra Zieliska Eliana B. Souto Karolina Wielgus 《International journal of molecular sciences》2021,22(9)
As the major nonpsychotropic constituent of Cannabis sativa, cannabidiol (CBD) is regarded as one of the most promising therapeutic agents due to its proven effectiveness in clinical trials for many human diseases. Due to the urgent need for more efficient pharmacological treatments for several chronic diseases, in this review, we discuss the potential beneficial effects of CBD for Alzheimer’s disease, epilepsy, multiple sclerosis, and neurological cancers. Due to its wide range of pharmacological activities (e.g., antioxidant, anti-inflammatory, and neuroprotective properties), CBD is considered a multimodal drug for the treatment of a range of neurodegenerative disorders, and various cancer types, including neoplasms of the neural system. The different mechanisms of action of CBD are here disclosed, together with recent progress in the use of this cannabis-derived constituent as a new therapeutic approach. 相似文献
679.
Izabela Wysocka Aleksandra Mielewczyk-Gryń Marcin Łapiński Bartłomiej Cieślik Andrzej Rogala 《International Journal of Hydrogen Energy》2021,46(5):3847-3864
Carbon dioxide and methane are two of the principal greenhouse gases. Reduction of their content in the atmosphere is currently the subject of much worldwide research. Dry and combined reforming of methane are effective methods of CO2 and CH4 utilization and production of synthesis gas (syngas) in chemical technology. Testing of catalysts that provide the desired H2/CO ratio and long operation time is one of the critical aspects of syngas production and the focus of much study. In this study, K-promoted Ni/MgAl2O4 catalysts prepared using a co-precipitation-impregnation method with different K/Ni ratios (range of 0–0.15) were examined in dry reforming of methane (DRM). The obtained catalysts were characterized using X-ray diffractometry (XRD), atomic emission spectrometry (MP-AES), Brunauer–Emmett–Teller (BET) specific surface area, BJH pore size distribution, TEM imaging, analysis of reducibility H2-TPR, infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Hammet basicity analysis, thermogravimetric analysis (TG) and elemental carbon-hydrogen-nitrogen analysis (CHN). Promotion of nickel catalysts with potassium led to changes in nickel distribution, metal-support interactions and deceleration of carbon deposition while enhancing sorption of carbon dioxide and reduction of nH2:CO to 0.5 for 0.7 K–Ni/MgAl2O4 catalyst. To obtain the required H2:CO ratio close to unity a study on the effect of steam in inlet stream was performed. It was found that maintaining inlet stream composition equal CH4:CO2:H2O = 1.0:1.0:0.1 obtained an H2:CO ratio close to unity. 相似文献
680.
Jelena Čakarević Aleksandra Torbica Miona Belović Jelena Tomić Tea Sedlar Ljiljana Popović 《International Journal of Food Science & Technology》2021,56(7):3400-3408
In this paper, valorisation of pumpkin oil cake as source of new protein carrier material for encapsulation was examined in order to enrich real food products. Cookies were used as a model system for addition of encapsulates at three different levels: 10%, 15% and 20%. The physicochemical and sensory properties were investigated, as well as conditions of stability after storage, in terms of total phenolic and betalain content. Furthermore, antioxidant, α-glucosidase and ACE inhibitory potential of cookies was evaluated after simulated gastrointestinal digestion. The cookies showed good technological quality as well as acceptable sensorial properties. The addition of encapsulate increases the total phenolic and betalain contents and shoved significant stability during storage time. Novel peptides were produced after gastrointestinal digestion, which enhanced bioactive properties of enriched products through synergistic action with active compounds from beetroot juice. Obtained digest shoved significant antioxidant, antidiabetic and antihypertension activities, hence ensuring a potential healing effect that could be reached by consuming these cookies. 相似文献