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41.
Betulin and its derivatives, 28-propyne derivative EB5 and 29-diethyl phosphonate analog ECH147, are promising compounds in anti-tumor activity studies. However, their effect on kidney cells has not yet been studied. The study aimed to determine whether betulin and its derivatives—EB5 and ECH147—influence the viability and oxidative status of human renal proximal tubule epithelial cells (RPTECs). The total antioxidant capacity of cells (TEAC), lipid peroxidation product malondialdehyde (MDA) level, and activity of antioxidant enzymes (SOD, CAT, and GPX) were evaluated. Additionally, the mRNA level of genes encoding antioxidant enzymes was assessed. Cisplatin and 5-fluorouracil were used as reference substances. Betulin and its derivatives affected the viability and antioxidant systems of RPTECs. Betulin strongly reduced TEAC in a concentration-dependent manner. All tested compounds caused an increase in MDA levels. The activity of SOD, CAT, and GPX, and the mRNA profiles of genes encoding antioxidant enzymes depended on the tested compound and its concentration. Betulin showed an cisplatin-like effect, indicating its nephrotoxic potential. Betulin derivatives EB5 and ECH147 showed different impacts on the antioxidant system, which gives hope that these compounds will not cause severe consequences for the kidneys in vivo.  相似文献   
42.
One of the strategies in the search for safe and effective analgesic drugs is the design of multitarget analgesics. Such compounds are intended to have high affinity and activity at more than one molecular target involved in pain modulation. In the present contribution we summarize the attempts in which fentanyl or its substructures were used as a μ-opioid receptor pharmacophoric fragment and a scaffold to which fragments related to non-opioid receptors were attached. The non-opioid ‘second’ targets included proteins as diverse as imidazoline I2 binding sites, CB1 cannabinoid receptor, NK1 tachykinin receptor, D2 dopamine receptor, cyclooxygenases, fatty acid amide hydrolase and monoacylglycerol lipase and σ1 receptor. Reviewing the individual attempts, we outline the chemistry, the obtained pharmacological properties and structure-activity relationships. Finally, we discuss the possible directions for future work.  相似文献   
43.
In this article an attempt to determine the influence of mining factors on the seismic activity during the longwall mining of the upper layer of coal seam no. 405/2 in one of the Polish hard coal mines in the Upper Silesian Coal Basin was conducted. Two longwall panels were mined in analogous geological conditions and based on the same mining system and technology. However, there was significant difference with regards to the mining factors, which was reflected in the observed seismic activity. Some tools used in mining seismology were applied to illustrate the aforementioned influence of mining factors, e.g. the frequency-energy distribution, the frequency-magnitude distribution, the 2 D distribution of released seismic energy, the relationship between released seismic energy and the volume of mined coal, the Benioff strain release, and the Gutenberg-Richter(GR) b coefficient distribution(b is the proportion between high and low energy tremors). Concerning the Benioff strain release, a new solution, based on the slope of a fitted line in a moving time window, is proposed.  相似文献   
44.
Starch and beta-glucan are most abundant carbohydrate polymers available in oat products; however, their simultaneous release during extraction depends on morphological and processing conditions of raw material. The study analyzes the mutual correlation between the sample (oat flakes and bran) and treatment types (microwave heating (MW)—1–5 min; conventional heating (CH)—7 min) on water extract properties focusing on beta-glucan, starch, and glucose content as well as the antioxidant activity of water extracts. The strong negative partial coefficient correlation was found between solids-starch (??0.65) and starch-glucose (??0.89) content as well as DPPH (??0.66) antioxidant activity in oat flakes revealing the high release of glucose to the water phase and its prooxidant activity. For the oat bran, positive and very high partial coefficient was found for both glucose (0.98) and beta-glucan (0.98) content in solids while the mutual interaction between them was highly negative (??0.97), meaning the more beta-glucan, the less glucose in the water phase.  相似文献   
45.
One application of the P300 brain electric signal is sentence spelling, which enables subjects who have lost control of their motor pathways to communicate by selecting characters in a matrix containing all alphabet symbols. This technology still suffers from both low communication/high error rates. A P300 speller, named PolyMorph, which jointly introduces the selection matrix polymorphism (reducing the matrix size by removing useless symbols) and sentence-based predictions (which forecast words on the basis of language statistics) is presented. This is accomplished by using a custom dynamic knowledge-base, tailored to the subject lexicon, and updated in real time with the selections of the subject. The effectiveness of the presented speller is measured in vivo and in silico. The results suggest that the use of PolyMorph increases the number of spelt characters per time unit and reduces the error rate.  相似文献   
46.
Tryptophan (Trp) is an amino acid and an essential component of the human diet. It plays a crucial role in many metabolic functions. Clinicians can use Trp levels in the course of diagnosing various metabolic disorders and the symptoms associated with those diseases. Furthermore, supplementation with this amino acid is considered in the treatment of depression and sleep disorders, mainly due to the Trp relationship with the synthesis of serotonin (5-HT) and melatonin. It is also used in helping to resolve cognitive disorders, anxiety, or neurodegenerative diseases. Reduced secretion of serotonin is associated with autism spectrum disorder, obesity, anorexia and bulimia nervosa, and other diseases presenting peripherals symptoms. The literature strongly suggests that Trp has a significant role in the correct functionality of the brain-gut axis and immunology. This information leads to the consideration of Trp as an essential dietary component due to its role in the serotonin pathway. A reduced availability of Trp in diet and nutraceutical supplementation should be considered with greater concern than one might expect. This paper constitutes a review of the more salient aspects gleaned from the current knowledge base about the role of Trp in diseases, associated nutritional disorders, and food science, in general.  相似文献   
47.
ATR, a DNA damage signaling kinase, is required for cell cycle checkpoint regulation and detecting DNA damage caused by genotoxic factors including Al3+ ions. We analyzed the function of the HvATR gene in response to chemical clastogen-maleic acid hydrazide (MH). For this purpose, the Al-tolerant barley TILLING mutant hvatr.g was used. We described the effects of MH on the nuclear genome of hvatr.g mutant and its WT parent cv. “Sebastian”, showing that the genotoxic effect measured by TUNEL test and frequency of cells with micronuclei was much stronger in hvatr.g than in WT. MH caused a significant decrease in the mitotic activity of root cells in both genotypes, however this effect was significantly stronger in “Sebastian”. The impact of MH on the roots cell cycle, analyzed using flow cytometry, showed no differences between the mutant and WT.  相似文献   
48.
Powders of α-TCP containing various amounts of silicon were synthesized by two different methods: Wet chemical precipitation and solid-state synthesis. The obtained powders were then physico–chemically studied using different methods: Scanning and transmission electron microscopy (TEM and SEM), energy-dispersive X-ray spectroscopy (EDS), powder X-ray diffractometry (PXRD), infrared and Raman spectroscopies (FT-IR and R), and solid-state nuclear magnetic resonance (ssNMR). The study showed that the method of synthesis affects the morphology of the obtained particles, the homogeneity of crystalline phase and the efficiency of Si substitution. Solid-state synthesis leads to particles with a low tendency to agglomerate compared to the precipitation method. However, the powders obtained by the solid-state method are less homogeneous and contain a significant amount of other crystalline phase, silicocarnotite (up to 7.33%). Moreover, the microcrystals from this method are more disordered. This might be caused by more efficient substitution of silicate ions: The silicon content of the samples obtained by the solid-state method is almost equal to the nominal values.  相似文献   
49.
50.
In this study, the influence of sonication time on the biogenic amines formation as a critical point in uncured dry-fermented beef manufacturing was studied. Samples of musculus semimembranosus were sonicated at different times (5 and 10 min) using ultrasound cold bath (4 °C) in acid whey (US 40 kHz and acoustic power 480 W). The effect of sonication on biogenic amine (BA) formation was investigated during 93 days of ripening period. Other parameters (pH value, water activity, microbial counts) that might provide further information on the product under study were also determined. The use of ultrasound during beef marinating in acid whey has a positive effect on retarding histamine (HIS), cadaverine (CAD), tyramine (TYR) and putrescine (PUT) formation. Moreover, the sonication treatment did not inhibit the growth of lactic acid bacteria (LAB) in dry-fermented beef during the whole ripening period. The pathogen bacteria (Staphylococcus aureus, Clostridium sp., Listeria monocytogenes) were not detected in all samples neither after 31 nor after 93 days of ripening period.  相似文献   
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