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61.
Chiral Schiff base ligands (S)-H(2)L and (R)-H(2)L and their complexes (S-Ni-L, R-Ni-L, S-Cu-L, R-Cu-L, S-Zn-L and R-Zn-L) were synthesized, characterized and examined for their DNA binding, antioxidant and antibacterial activities. The complexes showed higher binding affinity to calf thymus DNA with binding constant ranging from 2.0×10(5) to 4.5×10(6) M(-1). All the complexes also exhibited remarkable superoxide (56-99%) and hydroxyl scavenging (45-89%) activities as well as antibacterial activities against gram (+) and gram (-) bacteria. However, none of the complexes showed antifungal activity. Conclusively, S enantiomers of the complexes were found to be relatively more efficient for DNA interaction, antioxidant and antibacterial activities than their R enantiomers. This study reveals the possible utilization of chiral Schiff base complexes for pharmaceutical applications.  相似文献   
62.
The DNA binding studies of the triterpenoid derivative, cholesterol, N,N-Bis(3β-acetoxy-5α-cholest-6-yl-idene)hydrazine (L) with CT DNA were carried out by employing different optical methods viz, UV–vis and fluorescence spectroscopy. The ligand binds to DNA through hydrophobic interaction with Kb value found to be 4.7×103 M?1. These observations have been validated also by fluorescence spectroscopy. (L) exhibits a remarkable DNA cleavage activity with pBR322 DNA in the presence of different activators and the DNA is probably cleaved by an other than oxidative mechanism, possibly by a discernable hydrolytic pathway. In the presence of major and minor groove binding agents, (L) prefers major groove binding of the DNA.  相似文献   
63.
Catalysis Surveys from Asia - The over-consumption of petroleum fuel due to the progressive increase in population, transportation, industrialization, modernization as well as improvement in the...  相似文献   
64.
Journal of Thermal Analysis and Calorimetry - The present research is manifested to observe the impact of double stratification in the Marangoni convective flow of the Casson nanoliquid model...  相似文献   
65.
Irshad  M.  Ali  Q.  Iram  F.  Ahmad  S. A.  Saleem  M.  Saadia  M.  Batool  M.  Kanwal  A.  Tabassum  S. 《Russian Journal of General Chemistry》2019,89(8):1734-1734
Russian Journal of General Chemistry - The fourth author of the article should read S. A. Ahmadaa.  相似文献   
66.
Lucky Cement Factory, Pezu is using limestone of Sheikh Buddin Hills as a raw material in cement. Workers of the factory have direct and general public have indirect exposure to radiological hazard due to natural radionuclides present in limestone. To address the radiological hazards, limestone, mixed (limestone+clay) and cement samples were evaluate for concentrations of 222Rn and 226Ra using CR-39, RAD7 and HPGe detectors. Maximum mean values of 222Rn using CR-39 and RAD7 detectors were found 1447 ± 198 and 1416 ± 74 Bq.m?3 in cement samples and minimum were found in 536 ± 122 and 525 ± 45 Bq.m?3 limestone samples, respectively. Maximum mean value of radon exhalation rate of 12.28 ± 1.68 Bq.m?2 h?1 in cement samples was found below the world average value of 57.6 Bq.m?2 h?1. Maximum mean values of 226Ra measured by CR-39 and HPGe detectors were found 24.25 ± 3.35 and 23.6 ± 0.70 Bq.kg?1 in cement samples and minimum were found in 8.98 ± 2.02 and 9.19 ± 0.40 Bq.kg?1 limestone samples, respectively. A positive correlations (R2 = 0.9714) using CR-39 and RAD7 detectors and (R2 = 0.9573) using CR-39 and HPGe detectors were obtained for the concentrations of 222Rn and 226Ra, respectively. Maximum mean value of annual effective dose of 347.78 ± 47.58 µSv.y?1 in cement samples was found below the world average value of 1100 µSv.y?1.  相似文献   
67.
Meglumine efficiently catalyzes the one-pot, five-component reaction of hydrazine, ethyl acetoacetate, aryl aldehydes, substituted phenylacetonitriles and ammonium acetate in ethanol at room temperature to afford novel 4,7-dihydro-1H-pyrazolo[3,4-b]pyridin-6-amine derivatives. The present approach offers several advantages such as shorter reaction durations, low cost, excellent yields, milder reaction conditions, simple workup procedure and is environment friendly. All the synthesized derivatives are characterized by IR, 1H NMR, 13C NMR, HRMS and CHN analysis.  相似文献   
68.
This paper described a simple novel technique to prepare magnetic nano‐composite particles coated with highly crosslinked poly(lauryl methacrylate) (PLMA), a hydrophobic polymer because of its long chain alkyl group for application in waste water purification. Nano‐sized magnetite (Fe3O4) particles prepared by coprecipitation of Fe2+ and Fe3+ from their alkali aqueous solution were encapsulated with SiO2 following treatment with tetraethylorthosilicate (TEOS). Finally precipitation copolymerization of LMA and divinyl benzene (DVB) in the presence of Fe3O4/SiO2 particles was carried out within stable isolated droplets containing hexadecane–toluene mixture (4:1 mixture HD‐T). The produced PLMA‐coated magnetic composite particles named as Fe3O4/SiO2/P(LMA‐DVB) were characterized by Fourier Transform IR (FTIR), transmission electron microscopy (TEM), thermogravimetry (TG) and X‐ray diffractometer (XRD) analyses. The performance of the composite particles was evaluated for the removal of organic pollutants from water. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
69.
Metabolic disorders often lead to cardiac complications. Metabolic deregulations during diabetic conditions are linked to mitochondrial dysfunctions, which are the key contributing factors in cardiac hypertrophy. However, the underlying mechanisms involved in diabetes-induced cardiac hypertrophy are poorly understood. In the current study, we initially established a diabetic rat model by alloxan-administration, which was validated by peripheral glucose measurement. Diabetic rats displayed myocardial stiffness and fibrosis, changes in heart weight/body weight, heart weight/tibia length ratios, and enhanced size of myocytes, which altogether demonstrated the establishment of diabetic cardiac hypertrophy (DCH). Furthermore, we examined the expression of genes associated with mitochondrial signaling impairment. Our data show that the expression of PGC-1α, cytochrome c, MFN-2, and Drp-1 was deregulated. Mitochondrial-signaling impairment was further validated by redox-system dysregulation, which showed a significant increase in ROS and thiobarbituric acid reactive substances, both in serum and heart tissue, whereas the superoxide dismutase, catalase, and glutathione levels were decreased. Additionally, the expression levels of pro-apoptotic gene PUMA and stress marker GATA-4 genes were elevated, whereas ARC, PPARα, and Bcl-2 expression levels were decreased in the heart tissues of diabetic rats. Importantly, these alloxan-induced impairments were rescued by N-acetyl cysteine, ascorbic acid, and selenium treatment. This was demonstrated by the amelioration of myocardial stiffness, fibrosis, mitochondrial gene expression, lipid profile, restoration of myocyte size, reduced oxidative stress, and the activation of enzymes associated with antioxidant activities. Altogether, these data indicate that the improvement of mitochondrial dysfunction by protective agents such as N-acetyl cysteine, selenium, and ascorbic acid could rescue diabetes-associated cardiac complications, including DCH.  相似文献   
70.
The drugs used to treat cancer not only kill fast-growing cancer cells, but also kill or slow the growth of healthy cells, causing systemic toxicities that lead to altered functioning of normal cells. Most chemotherapeutic agents have serious toxicities associated with their use, necessitating extreme caution and attention. There is a growing interest in herbal remedies because of their pharmacological activities, minimal side effects, and low cost. Thymoquinone, a major component of the volatile oil of Nigella sativa Linn, also known as black cumin or black seeds, is commonly used in Middle Eastern countries as a condiment. It is also utilized for medicinal purposes and possesses antidiabetic, anti-cancer, anti-inflammatory, hepatoprotective, anti-microbial, immunomodulatory, and antioxidant properties. This review attempts to compile the published literature demonstrating thymoquinone’s protective effect against chemotherapeutic drug-induced toxicities.  相似文献   
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