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Plants have paved the way for the attainment of molecules with a wide-range of biological activities. However, plant products occasionally show low biological activities and/or poor pharmacokinetic properties. In that case, development of their derivatives as drugs from the plant world has been actively performed. As plant products, plastoquinones (PQs) have been of high importance in anticancer drug design and discovery; we have previously evaluated and reported the potential cytotoxic effects of a series of PQ analogs. Among these analogs, PQ2, PQ3 and PQ10 were selected for National Cancer Institute (NCI) for in vitro screening of anticancer activity against a wide range of cancer cell lines. The apparent superior anticancer potency of PQ2 on the HCT-116 colorectal cancer cell line than that of PQ3 and PQ10 compared to other tested cell lines has encouraged us to perform further mechanistic studies to enlighten the mode of anti-colorectal cancer action of PQ2. For this purpose, its apoptotic effects on the HCT-116 cell line, DNA binding capacity and several crucial pharmacokinetic properties were investigated. Initially, MTT assay was conducted for PQ2 at different concentrations against HCT-116 cells. Results indicated that PQ2 exhibited significant cytotoxicity in HCT-116 cells with an IC50 value of 4.97 ± 1.93 μM compared to cisplatin (IC50 = 26.65 ± 7.85 μM). Moreover, apoptotic effects of PQ2 on HCT-116 cells were investigated by the annexin V/ethidium homodimer III staining method and PQ2 significantly induced apoptosis in HCT-116 cells compared to cisplatin. Based on the potent DNA cleavage capacity of PQ2, molecular docking studies were conducted in the minor groove of the double helix of DNA and PQ2 presented a key hydrogen bonding through its methoxy moiety. Overall, both in vitro and in silico studies indicated that effective, orally bioavailable drug-like PQ2 attracted attention for colorectal cancer treatment. The most important point to emerge from this study is that appropriate derivatization of a plant product leads to unique biologically active compounds.  相似文献   
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A new analytical approach based on fractionation was introduced for lead in lipstick samples. Different separation techniques including n-hexane, glycerol extraction, and activated carbon adsorption were used to characterize the lipid fraction, polar and aromatic components of the samples. Additionally, artificial saliva and food stimulant extractions were used for the risk assessment studies. Trace metal levels in fractions were determined by inductively coupled plasma-mass spectrometry. Method validation parameters in the total element determinations were defined in terms of detection limits, accuracy, and precision. The limits of detection and quantification were 0.02 and 0.07 mg kg?1 for Pb; whereas the repeatability and reproducibility of the results based on percent relative standard deviation were 3.0% and 7.2% for lead, respectively.  相似文献   
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New Hofmann type benzene clathrates in the form of M(CyHEA)2Ni(CN)4·2benzene (where CyHEA=2-(1-cyclohexenyl)ethylamine and M=Ni or Cd) have been prepared in powder form and FT-IR and Raman spectra have been reported. The results suggest that title compounds are similar in structure to Hofmann type clathrates and their structures consist of polymeric layers of |M-Ni(CN)4|∞ with the CyHEA molecule bounded to the metal atoms (M).  相似文献   
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In this study, we identify a generalization of q-Bernstein type operators and investigate approximation properties of a sequence of these operators . We estimate rate of approximation by modulus of continuity. We prove Voronovskaya type theorem for these operators.  相似文献   
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Oil content in sweet and bitter fennels was obtained 12.22% and 14.41%, respectively. The C(18:1 c6), C(18:2), C(18:1 c9) and C(16:0) acids corresponding to approximately 97% of total oil was recorded as principal fatty acids. The ratios of essential oil from sweet and bitter fennels were found similar (average 3.00%). trans-Anethole, estragole and fenchone were found to be the main constituents in both fennels. The compound with the highest value in the two oil samples was trans-anethole as 95.25% (sweet) and 75.13% (bitter). While estragole was found in bitter fennel oil in a remarkable amount (15.51%), sweet fennel oil contained small amounts of estragole (2.87%). Fenchone was found <1% in sweet and approximately 5% in bitter fennel. p-Anisaldehyde in bitter fennel essential oil, and alpha-pinene and gamma-terpinene in sweet fennel essential oil were not recorded, and these compounds were found very low or <1%.  相似文献   
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The current study presents the results of the activity of radionuclides in spa waters, and evaluates their radiological influences on the population consuming these waters in the Central and Eastern Black Sea regions of Turkey. Since these waters are used for therapy and consumption purposes unconsciously, their radiological impact on the people was computed by taking into consideration the annual intake through ingestion of 226Ra, 232Th, 40K, 137Cs and 222Rn. The mean activities were estimated to be 11.35 for gross alpha, 6.23 for gross beta, 2.96 for 226Ra, 0.42 for 232Th, 0.069 for 137Cs, 0.19 for 40K, and 267 Bq L–1 for 222Rn, respectively. The estimated effective doses from spa water were found to be 49.77 µSv a–1 (226Ra), 5.95 µSv a–1 (232Th), 0.07 µSv a–1 (137Cs), 0.83 µSv a–1 (40K) and 56.03 µSv a–1 (222Rn). These values were evaluated and compared with related verified values from literature. Also, physico-chemical characterizations of spa water samples considered in the current study were investigated. This study would be useful for consumers and official authorities for the assessment of radiation exposure risk due to usage of the considered spa waters.  相似文献   
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