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91.
Molecular Biology Reports - Phytotherapy has been used to treat a different type of diseases including cancer for a long time, and it was a source for different active anti-tumor agents. Oncolytic...  相似文献   
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Neurochemical Research - Post-translational modification (PTMs) of proteins by ubiquitin and ubiquitin-like modifiers such as interferon-stimulated gene 15 (ISG15) and small ubiquitin-related...  相似文献   
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Despite increased social awareness, marketing restraints, tobacco taxation, and available smoking cessation rehab programs, active and passive smoking remain a worldwide challenging epidemic and a key risk factor for cardiovascular diseases development. Although cardiovascular (CV) protection is more pronounced in women than in men due to estrogenic effects, tobacco cigarette smoking exposure seems to alter this protection by modulating estrogen actions via undefined mechanisms. Premenopausal cigarette smoking women are at higher risk of adverse CV effects than non-smokers. In this study, we investigated the impact of cigarette smoking on early CV injury after myocardial infarction (MI) in non-menopausal female mice. Aortic arch calcification, fibrosis, reactive oxygen species, and gene expression of inflammatory and calcification genes were exaggerated in mice exposed to cigarette smoke (CS). These findings suggest that aortic injury following MI, characterized by vascular smooth muscle cells transdifferentiation, calcification, inflammation, and collagen deposition but not cardiac dysfunction is exacerbated with CS exposure. The novel findings of this study highlight the importance of aortic injury on short and long-term prognosis in CS-exposed MI females. Linking those findings to estrogen alteration is probable and entails investigation.  相似文献   
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The diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Yponomeutidae), is the most serious pest of cauliflower fields in central Iran and its control is primarily based on pesticide sprays. Over the past years, a number of new pesticide compounds were introduced onto the market and some of them may cause adverse effects on natural populations of parasitoids associated with DBM. Excessive use of insecticides against the pest did not produce satisfactory results but has caused concerns about environmental pollution and increased pest resistance to chemicals. This research aims to study natural parasitism of pest on different cauliflower cultivars in the fields of south of Tehran. Dominant species of parasitoids include Diadegma anurum, Cotesia plutellae and Oomyzus sokolowskii. The highest parasitism rate was observed by D. anurum that was recorded on Buris cultivar (19.92?±?1.06) and White cloud cultivar (16.20?±?1.49) and the lowest parasitism rate was observed on Snow crown cultivar (3.42) and SG cultivar (5.00) during the season.  相似文献   
96.
Hydrogen sulphide (H2S) is one of three gaseous signaling molecules after nitric oxide and carbon monoxide. Various H2S donor compounds have been synthesized to study its physiological function. Among these compounds sodium hydrosulphide (NaHS), a donor of releasing H2S rapidly have shown to be protective in certain neuronal cell line but several in vivo studies have generated conflicting data. Furthermore several slow releasing H2S donors have been shown to have positive effects on cells in culture. The intracellular concentration of H2S and hence its rate of production may be a factor in keeping the balance between its neuroprotective and toxic effects. The present study was undertaken to deduce how a rapid releasing H2S donor (NaHS) as opposed to a slow releasing donor (ADTOH), affect oxidative stress related intracellular components and survival of RGC-5 cells. It was concluded that when RGC-5 cells are exposed to the toxic effects of glutamate in combination with buthionine sulfoxime (Glu/BSO), ADTOH was more efficacious in inhibiting apoptosis, scavenging reactive oxygen species (ROS), stimulation of glutathione (GSH) and gluthathione-S-transferase (GST). Western blot and qPCR analysis showed ADTOH increased the levels of Nrf2, HO-1, PKCα, p-Akt, Bcl-2 and XIAP but caused a decrease of Nfκβ and xCT greater than NaHS. This study is first to compare the efficacy of two H2S donor drugs as potential neuroprotectants and demonstrate that slow regulated release of H2S to cell culture can be more beneficial in inhibiting oxidative stress induced cell death.  相似文献   
97.
Catecholestrogens [4-hydroxyestradiol (4-OHE2)] have been implicated in human carcinogenesis, although the mechanism remains unestablished. In this study pUC 18 plasmid DNA was modified with 4-OHE2 and nitric oxide (NO). The modification induced in native DNA exhibited hyperchromicity, single strand breaks, damage to restriction sites, modification of bases, decrease in Tm and change in ellipticity. Modified DNA was found to be highly immunogenic in experimental animal, eliciting high titer antibodies. Circulating cancer autoantibodies showed preferable recognition of 4-OHE2-NO-DNA over native form (p < 0.001) and the oxidative epitopes on the DNA isolates from cancer patients were immunochemically detected by using experimentally induced anti-4-OHE2-NO-DNA antibodies as a probe. Preferential recognition of 4-OHE2-NO-DNA by cancer autoantibodies coupled with enhanced binding of induced antibodies to DNA isolated from cancer patients is an indicative of oxidative stress induced DNA damage in cancer. Possible involvement of unique epitopes on modified DNA in cancer autoantibody induction has been suggested.  相似文献   
98.
Abstract

We report the first use of exciplex-based split-probes for detection of the wild type and *3 mutant alleles of human cytochrome P450 2C9. A tandem 8-mer split DNA oligonucleotide probe system was designed that allows detection of the complementary target DNA sequence. This exciplex-based fluorescence detector system operates by means of a contiguous hybridization of two oligonucleotide exciplex split-probes to a complementary target nucleic acid target. Each probe oligonucleotide is chemically modified at one of its termini by a potential exciplex-forming partner, each of which is fluorescently silent at the wavelength of detection. Under conditions that ensure correct three-dimensional assembly, the chemical moieties on suitable photoexcitation form an exciplex that fluoresces with a large Stokes shift (in this case 130 nm). Preliminary proof-of-concept studies used two 8-mer probe oligonucleotides, but in order to give better specificity for genomic applications, probe length was extended to give coverage of 24 bases. Eight pairs of tandem 12-mer oligonucleotide probes spanning the 2C9*3 region were designed and tested to find the best set of probes. Target sequences tested were in the form of (i) synthetic oligonucleotides, (ii) embedded in short PCR products (150 bp), or (iii) inserted into plasmid DNA (~ 3 Kbp). The exciplex system was able to differentiate wild type and human cytochrome P450 2C9 *3 SNP (1075 A→C) alleles, based on fluorescence emission spectra and DNA melting curves, indicating promise for future applications in genetic testing and molecular diagnostics.  相似文献   
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