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İrfan Koca Aykut Özgür Kübra Açikalin Coşkun Yusuf Tutar 《Bioorganic & medicinal chemistry》2013,21(13):3859-3865
In this work novel organic based compounds, acyl thiourea derivatives were synthesized and their anticancer activities were investigated. A new series of acyl thiourea derivatives containing pyrazole ring were prepared in good yield through one pot reaction of 4-benzoyl-1, 5-diphenyl-1H-pyrazole-3-carbonyl chloride with ammonium thiocyanate and various amines. The structures of the newly synthesized compounds were confirmed by IR, 1H NMR, 13C NMR and elemental analysis. Anticancer activities of synthesized compounds were evaluated on human colon, liver and leukemia cancer cell lines. Cell culture studies have demonstrated significant toxicity of the compounds on the cell lines, and the levels of toxicity have altered in the presence of various side groups. These results confirm that novel pyrazolyl acyl thioureas derived compounds may be utilized for cancer treatment. Furthermore, these compounds have a great potential and significance for further investigations. 相似文献
994.
Darinka Gjorgieva Tatjana Kadifkova Panovska Tatjana Ruskovska Katerina Bačeva Trajče Stafilov 《Physiology and Molecular Biology of Plants》2013,19(4):499-507
The present study aimed to analyze the biological effects induced by bioaccumulation of metals in common bean (Phaseolus vulgaris L.). Effects of mineral nutrient imbalance, total antioxidants level and DNA damage induced by accumulation of heavy metals, were investigated in bean seedlings treated with two selected metal concentrations for 7 days. Metal content is analyzed by inductively coupled plasma – atomic emission spectrometer (ICP-AES), for total antioxidants level assessment the Ferric-Reducing Antioxidant Power (FRAP) assay is used and Random Amplified Polymorphic DNA (RAPD) method was applied for investigation of DNA damages. The increasing metal concentration in the treatment medium changed synchronously metal content in samples, and decreased total antioxidant activity in all samples with exception only for samples treated with Ni and Cd. The obtained “DNA fingerprints” demonstrated that the increasing metal concentrations induced changes in RAPD profiles (disappearance and/or appearance of bands in comparison with untreated control samples). The highest number of missing bands was observed in samples treated with zinc (total 4 bands) and nickel (total 4 bands) at both concentrations. These results suggested that mineral nutrient imbalance is involved in changes of antioxidant levels and DNA damages of the seedlings, which may help to understand the mechanism of metal toxicity in plants. 相似文献
995.
This study aimed to determine the age and some growth characteristics of Atlantic stargazer (Uranoscopus scaber) from Iskenderun Bay (Northeastern Mediterranean). For this purpose, a total of 150 Atlantic stargazer ranging in size from 9.1 to 28.0 cm in total length (weight: 11.7–345.7 g) were collected as by-catch from a commercial trawl fishing boat at a depth of 80–100 m between May 2015 and January 2016. The bottom trawl gear used was equipped with a 44 mm stretched mesh size net at the cod-end. The percentage of females and males were 46.7% and 53.3% respectively. The total length–weight relationships equation with coefficient of determination (R2) were found as W = 0.011*TL3.131, R2 = .9728, for all individuals, W = 0.015*TL3.021, R2 = .9512 for females and W = 0.0102*TL3.136, R2 = .9553 for males. By using the von Bertalanffy equation, the growth parameters of Atlantic stargazer were estimated to be L∞ = 42.35 cm, k = 0.098, t0 = −1.8474 for all individuals; L∞ = 36.92 cm, k = 0.138, t0 = −1.2693 for females and L∞ = 38.77 cm, k = 0.1, t0 = −2.334 for males. In this study, age reading was done by two independent readers and index of average percentage error (IAPE) was calculated as 6.1%. The highest condition factor value calculated as 1.81 in the age group 6 and the lowest condition factor value was calculated as 1.48 in the age group 1. 相似文献
996.
Yudong Shang Zhengyao Zhang Hengxing Ba Datao Wang Xiaoyan Qi 《Journal of biomolecular structure & dynamics》2020,38(7):2068-2079
AbstractS100A4 is a multiple-function protein highly expressed in tumor or stem cells. We found S100A4 was a novel protein partner for heat shock protein 47 (HSP47) in deer antlerogenic periosteum cells (AP cells), indicating that S100A4 could bind with HSP47. S100A4 had both calcium-dependent and calcium-independent patterns (labeled as SCd and SCi, respectively) to execute different biological activities. Homology models of HSP47, SCd and SCi were constructed. HSP47:collagen model, HSP47:collagen I-V, HSP47:SCd and HSP47:SCi complexes were built using ZDOCK software. Together with free SCd and SCi, 200?ns molecular dynamic (MD) simulations were performed to analyze binding free energies and SCi/SCd conformational changes. The energetic results showed that SCi had the strongest affinity to HSP47, and followed by collagens. SCd had little interaction with HSP47. Decomposition energy results showed that collagen model interacted with HSP47 mainly though neutral amino acids. When SCi bound with HSP47, the majority of mediated amino acids were charged. These results indicated that SCi could compete with collagen on the binding site of HSP47. Root mean square fluctuation (RMSF) values and cross-correlation matrices of principal component analysis (PCA) were calculated to evaluate the SCi/SCd structural variation during MD simulation. Both HSP47 and Ca2+ could stabilize the conformation of SCi/SCd. The loops interacting with Ca2+s and linking the two EF-hand motifs were impacted particularly. The relative moving directions of α-helices in EF-hands were distinct by the binding effect of HSP47 and Ca2+. We found that SCi may regulate the differentiation of AP cells by disturbing the interaction between HSP47 and collagen. Communicated by Ramaswamy H. Sarma 相似文献
997.
Hela Mahmoudi Rym Kaddour Jun Huang Nawel Nasri Baâtour Olfa Sabah M’Rah Abdelali Hannoufa Mokhtar Lachaâl Zeineb Ouerghi 《Acta Physiologiae Plantarum》2011,33(5):1613-1622
Salt stress perturbs a multitude of physiological processes such as photosynthesis and growth. To understand the biochemical
changes associated with physiological and cellular adaptations to salinity, two lettuce varieties (Verte and Romaine) were
grown in a hydroponics culture system supplemented with 0, 100 or 200 mM NaCl. Verte displayed better growth under 100 mM
NaCl compared to Romaine, but both genotypes registered relatively similar reductions in growth under 200 mM NaCl treatment.
Both varieties showed differences in net photosynthetic activity in the absence of salt and 8 days after salt treatment. These
differences diminished subsequently under prolonged salt stress (14 days). Verte showed enhanced leaf proline and restricted
total cations especially Na+, lesser malondialdehyde (MDA) formation and lignification in the roots under 100 mM NaCl salinity. Membrane damage estimated
by electrolyte leakage increased with elevated salt concentrations in roots of both varieties, but Verte had significantly
lower electrolyte leakage relative to Romaine under 100 mM NaCl. Moreover, Verte also accumulated greater levels of carotenoids
under increasing NaCl concentrations compared to Romaine. Taken together, these findings suggest that the greater tolerance
of Verte to 100 mM NaCl is related to the more restricted accumulation of total cations and toxic Na+ in the roots and enhanced levels of antioxidative metabolites in root and leaf tissue. 相似文献
998.
The probiotic characteristics of Lactobacillus brevis BG18 and Lb. plantarum BG33, isolated from traditional Turkish Tulum cheese were assessed. These two bacteriocinproducer strains exhibited good probiotic characteristics such as resistance in media containing 0.3% bile salt, pepsin (3 mg mL?1), and pancreatine (1 mg mL?1) as well as acid resistance at pH 2. They were also adhered to Caco-2 epithelial cells in a manner comparable to Escherichia coli LMG3083 (ETEC) and Salmonella Typhimurium SL1344. The strains produced a heat-stable antimicrobial compound that was shown to be proteinaceous in nature, and therefore, referred to as bacteriocins. The bacteriocins were able to inhibit growth of a number grampositive bacteria such as Listeria monocytogenes, Clostridium botulinum, Staphylococcus aureus and Bacillus cereus. Tricine-SDS-PAGE of the active fraction resulted in single bands with estimated molecular masses of 2.5 kDA and 2.7 kDA for Lb. brevis BG18 and Lb. plantarum BG33 bacteriocins, respectively. 相似文献
999.
Tanrikulu S Doğru-Abbasoğlu S Ozderya A Ademoğlu E Karadağ B Erbil Y Uysal M 《Cell biochemistry and function》2011,29(3):244-248
Oxidative DNA damage, caused by either endogenous or exogenous sources of reactive oxygen species (ROS), has been linked several diseases including Graves' disease (GD). 7,8‐Dihydro‐8‐oxoguanine (8‐oxoG) is a major lesion produced by ROS and is considered a key biomarker of oxidative DNA damage. In humans, 8‐oxoG is mainly repaired by 8‐oxoguanine DNA N‐glycosylase‐1 (hOGG1), which is an essential component of the base excision repair (BER) pathway. The functional studies showed that hOGG1 Ser326Cys polymorphism is associated with the reduced DNA repair activity and increased risk for some oxidative stress‐related diseases. In this study, we firstly investigated hOGG1 Ser326Cys polymorphism in GD. According to our results, Cys/Cys genotype frequency in the GD patients (23.4%) was significantly higher than the controls (9.2%). Cys/Cys genotype had an 3.5‐fold [95% CI (confidence interval): 2.10–6.01, p < 0.001] the Cys allele had 1.83‐fold (95% CI: 1.43–2.34, p < 0.001) increase in the risk for developing GD. Our results suggest that Ser326Cys polymorphism of the hOGG1 gene is associated with GD risk. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
1000.