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11.
BackgroundSchiff base metal complexes are considered promising chemotherapeutic agents due to their potential application in cancer therapy.MethodsThe current work sought to synthesize a brand-new Schiff base ligand obtained from 2-hydroxybenzohydrazide and (E)− 1-(2-(p-tolyl)hydrazono)propan-2-one with metal ions which included Pd(II) and Zn(II) ions. Elemental analyses, FT-IR, mass spectra, 1H NMR, UV-Vis spectrometer, and computational analysis characterized the compound's structure. In vitro, the breast cancer cell line (MCF-7) was tested for its sensitivity to Schiff base (HL) and its Pd(II) and Zn(II) complexes. The half-maximal inhibitory concentration IC50 of the compounds was determined and used to perform the comet assay, which was carried out to reveal the photo-induced DNA damaging ability of the compounds of individual cells. Moreover, the compounds' effects on antioxidant defense systems of enzymes in cells: superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities and oxidant Malondialdehyde (MDA) were examined in MCF-7 cells.ResultsThe Pd(II) complex displayed approximately the same IC50 as Cisplatin, while Zn(II) complex had better activity than Cisplatin with very low IC50, 1.40 μg/ml. Significant alterations in SOD, CAT, GPx, and MDA production were discovered, inducing oxidative stress, enlarging ROS production, and reducing the antioxidant amount. This change was approximately similar in most compounds. Consequently, it promoted apoptosis, particularly the Zn(II) complex, which demonstrated an improved impact because of its ability to influence the antioxidant defense systems of enzymes, mostly SOD and GPx, besides increasing MDA levels.ConclusionIt can be concluded that Zn(II) complex is the most effective anticancer drug since it induced a very similar genotoxic effect as Cisplatin and has a very low IC50 value. 相似文献
12.
《Journal of molecular biology》2023,435(13):168129
Mitochondrial protein import is critical for organelle biogenesis, bioenergetic function, and health. The mechanism of which is poorly understood, particularly of the mammalian system. To address this problem we have established an assay to quantitatively monitor mitochondrial import inside mammalian cells. The reporter is based on a split luciferase, whereby the large fragment is segregated in the mitochondrial matrix and the small complementary fragment is fused to the C-terminus of a purified recombinant precursor protein destined for import. Following import the complementary fragments combine to form an active luciferase–providing a sensitive, accurate and continuous measure of protein import. This advance allows detailed mechanistic examination of the transport process in live cells, including the analysis of import breakdown associated with disease, and high-throughput drug screening. Furthermore, the set-up has the potential to be adapted for the analysis of alternative protein transport systems within different cell types, and multicellular model organisms. 相似文献
13.
This article presents for the first time a modified protocol for RNase protection analysis that allows the substitution of32P with33P without loss of the high sensitivity of this method achieved with32P. With this protocol, we were able to detect at least 1 pg of specific mRNA. In the RNase protection analysis33P labeled riboprobes are more advantageous with regard to an easier handling and better resolution. 相似文献
14.
Craig J. Coates Catherine L. Turney Marianne Frommer David A. O'Brochta W. D. Warren Peter W. Atkinson 《Molecular & general genetics : MGG》1995,249(2):246-252
Plasmid-based excision assays performed in embryos of two non-drosophilid species using the mariner transposable element from Drosophila mauritiana resulted in empty excision sites identical to those observed after the excision of mariner from D. mauritiana chromosomes. In the presence of the autonomous mariner element Mos1, excision products were recovered from D. melanogaster, D. mauritiana and the blowfly Lucilia cuprina. When a hsp82 heat shock promoter-Mos1 construct was used to supply mariner transposase, excision products were also recovered from the Queensland fruitfly Bactrocera tryoni. Analysis of DNA sequences at empty excision sites led us to hypothesise that the mariner excision/repair process involves the formation of a heteroduplex at the excision breakpoint. The success of these assays suggests that they will provide a valuable tool for assessing the ability of mariner and mariner-like elements to function in non-drosophilid insects and for investigating the basic mechanisms of mariner excision and repair. 相似文献
15.
16.
The state of the art of firefly luciferase research is reviewed with special emphasis on its purification and immobilization. The notion of bioluminescence and its role in APT monitoring is described. The need to purify luciferase and the advantages of immobilization are discussed. An insight into the existing methods of luciferase purification and immobilization is given. The scope of the bioluminescent assay is underlined. 相似文献
17.
A procedure for the assay of immobilized tannase with Polyacrylamide gel, collagen and Duolite-S-762 as matrices is described.
It is based on the spectrophotometric determination of gallic acid formed by the enzymatic hydrolysis of tannic acid. The
kinetic parameters of the enzymatic reaction have been studied and an assay procedure has been formulated. This method appears
to be much more accurate than those reported earlier. 相似文献
18.
A centrifugation binding assay has been used to demonstrate the binding of [3H] (±) abscisic acid to membrane-rich fractions prepared from leaves of Vicia faba L. Kinetic analysis of this binding shows evidence of saturation of binding sites with increasing concentration of ligand. Scatchard analysis of these data yields a biphasic plot possibly indicating the presence of two types of binding sites. The dissocation constant for the high affinity site has been calculated to be 3.5×10-8 mol 1-1. 相似文献
19.
Extracts of bovine aorta and nuchal ligament contain several large glycoproteins. The major glycoprotein species has been isolated and has been shown to be collagenase sensitive with an apparent molecular weight of 140,000 daltons. The protein exists in disulphide-bonded aggregates, contains hydroxyproline and hydroxylysine in 1:1 ratio and is unlike any of the known collagen types in amino acid analysis. Its presencein ligament extracts indicates that it is not derived from basement membranes. The evidence suggests that this protein is not derived from the microfibrillar components of the elastic tissues. 相似文献
20.
B. M. Wagland W. O. Jones L. Hribar T. Bendixsen D. L. Emery 《International journal for parasitology》1992,22(8):1183-1185
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,
,
and
1992. A new simplified assay for larval migration inhibition. International Journal for Parasitology 22: 1183–1185. A simple method is described for the in vitro detection of substances that impair the motility of third-stage larvae of gastro-intestinal nematodes. The test is based on the ability of larvae to freely migrate through selected mesh sizes of nylon sieves and the reduced ability of larvae to migrate after preincubation with, and in the presence of, substances that inhibit or reduce larval motility. 相似文献