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31.
In this study, we investigated the combined treatment of 5-fluorouracil (5-FU) and Anatolian propolis extract (PE) on colorectal cancer (CRC)using in vitro and in vivo studies. We exposed luciferase-transfected (Lovo-Luc CRC) cells and healthy colon cells (CCD-18Co) to varying concentrations of 5-FU and PE to assess their genotoxic, apoptotic, and cytotoxic effects, as well as their intracellular reactive oxygen species (iROS) levels. We also developed a xenograft model in nude mice and evaluated the anti-tumor effects of PE and 5-FU using various methods. Our findings showed that the combination of PE and 5-FU had selectivity against cancer cells, particularly at higher doses, and enhanced the anti-tumor effectiveness of 5-FU against colon CRC. The results suggest that PE can reduce side effects and increase the effectiveness of 5-FU through iROS generation in a dose-dependent manner.  相似文献   
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The water-distilled essential oil the leaves of Coridothymus capitatus were analyzed by GC/MS and also analyzed by direct thermal desorption GC/MS. Comparison was made between two analyses techniques. The essential oil consisted mainly of monoterpenes 98.9%, while oxygenated hydrocarbons were identified as 55.6 % and non-oxygenated hydrocarbons as 43.6%. As major components were found carvacrol (35.6%), p-cymene (21.0%), thymol (18.6%), gamma-terpinene (12.3%), alpha-terpinene (3.2%), beta-myrcene (3.0%) and alpha-thujene (1.3%) by hydrodistillation and by the GC/MS method. The direct thermal desorption GC/MS analysis also showed the same major components, namely carvacrol (51.6%), thymol (21.7%), p-cymene (9.7%) gamma-terpinene (8.2%), alpha-terpinene (1.64%). The essential oil of C. capitatus showed strong activity against S. aureus, P. vulgaris, P. aeruginosa, E. coli, K. pneumonia, B.  相似文献   
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Faced with the serious consequences resulting from the abusive and repeated use of synthetic chemicals, today rethinking crop protection is more than necessary. It is in this context that the essential oils of the Lamiaceae Ocimum gratissimum and Ocimum canum, the Poaceae Cymbopogon citratus and nardus and a Rutaceae Citrus sp. of known chemical compositions were experimented. The evaluation of the larvicidal potential of the essential oils was done by the method of topical application of the test solutions, on the L1−L2 stage larvae from the first generation of S. frugiperda obtained after rearing in an air-conditioned room. Lethal concentrations (LC10, LC50 and LC90) were determined after 48 h. After assessing the larvicidal potential of essential oils, molecular docking was carried out to study protein-ligand interactions and their propensity to bind to insect enzyme sites (AChE). The essential oil of O. gratissimum was the most effective with the lowest lethal concentrations (LC10=0.91 %, LC50=1.91 % and LC90=3.92 %). The least toxic oil to larvae was Citrus sp. (LC10=5.44 %, LC50=20.50 % and LC90=77.41 %). Molecular docking revealed that p-cymene and thymol from O. gratissimum essential oil are structurally similar and bind to the AChE active site via predominantly hydrophobic interactions and a H-bond with Tyr374 in the case of thymol. The essential oil of O. gratissimum constitutes a potential candidate for the development of biological insecticides for the fight against insect pests and for the protection of the environment.  相似文献   
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Brain tumors are the most common form of solid tumors in children and is presently a serious therapeutic challenge worldwide. Traditional treatment with chemotherapy and radiotherapy was shown to be unsuccessful in targeting brain tumor cancer stem cells (CSCs), leading to recurrent, treatment-resistant secondary malignancies. Oncolytic virotherapy (OV) is an effective antitumor therapeutic strategy which offers a novel, targeted approach for eradicating pediatric brain tumor CSCs by utilizing mechanisms of cell killing that differ from conventional therapies. A number of studies and some clinical trials have therefore investigated the effects of combined therapy of radiations or chemotherapies with oncolytic viruses which provide new insights regarding the effectiveness and improvement of treatment responses for brain cancer patients. This review summarizes the current knowledge of the therapeutic potency of OVs-induced CSCs targeting in the treatment of brain tumors for a better understanding and hence a better management of this disease.  相似文献   
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Biological Trace Element Research - The prevalence of hypertension (HTN) is increasing globally. It has been shown that there is an association between micronutrient deficiency and HTN. In the...  相似文献   
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It is known that K(ATP) channel openers inhibit the release and refilling of Ca(2+) from intracellular stores. The present study was designed to test the effects of levcromakalim in human umbilical artery (HUA) rings stimulated by serotonin (5-HT) and KCl in Ca-free medium. Umbilical cords were obtained at vaginal or cesarean deliveries from healthy, term pregnancies. After the isolation, HUA rings were placed in organ baths in solution with indomethacin (10(-5) M) and N(G)-nitro-L-arginine methyl ester (L-NAME) (10(-3) M) at 37 degrees C and aerated with 95% O(2) and 5% CO(2) for the measurement of isometric force. In Ca-free solution with Ethylene glycol-bis (ss-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) (2 mM) the contractions produced by 5-HT (10(-6) M) and KCl (40 mM) decreased significantly. Afterwards, HUA rings were treated with 5-HT and KCl in repeated manner in Ca-free medium. In contrast to KCl, 5-HT induced contractions reduced in each application, progressively. Levcromakalim (10(-4) M) abolished the contractions elicited by 5-HT. On the other hand, levcromakalim had a little but significant inhibitory effect on KCl induced contraction in Ca-free medium. These results suggest that Ca(2+) is not the only transduction pathway in KCl produced contractions of HUA smooth muscle cells.  相似文献   
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Human α-glucosidase is an enzyme involved in the catalytic cleavage of the glucoside bond and involved in numerous functionalities of the organism, as well as in the insurgence of diabetes mellitus 2 and obesity. Thus, developing chemicals that inhibit this enzyme is a promising approach for the treatment of several pathologies. Small peptides such as di- and tri-peptides may be in natural organism as well as in the GI tract in high concentration, coming from the digestive process of meat, wheat and milk proteins. In this work, we reported the first tentative hierarchical structure-based virtual screening of peptides for human α-glucosidase. The goal of this work is to discover novel and diverse lead compounds that my act as inhibitors of α-glucosidase such as small peptides by performing a computer aided virtual screening and to find novel scaffolds for further development. Thus, in order to select novel candidates with original structure we performed molecular dynamics (MD) simulations among the 12 top-ranked peptides taking as comparison the MD simulations performed on crystallographic inhibitor acarbose. The compounds with the lower RMSD variability during the MD, were reserved for in vitro biological assay. The selected 4 promising structures were prepared on solid phase peptide synthesis and used for the inhibitory assay, among them compound 2 showed good inhibitory activity, which validated our method as an original strategy to discover novel peptide inhibitors. Moreover, pharmacokinetic profile predictions of these 4 peptides were also carried out with binary QSAR models using MetaCore/MetaDrug applications.  相似文献   
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Traumatic injury to the brain or spinal cord and multiple sclerosis (MS) share a common pathophysiology with regard to axonal demyelination. Despite advances in central nervous system (CNS) repair in experimental animal models, adequate functional recovery has yet to be achieved in patients in response to any of the current strategies. Functional recovery is dependent, in large part, upon remyelination of spared or regenerating axons. The mammalian CNS maintains an endogenous reservoir of glial precursor cells (GPCs), capable of generating new oligodendrocytes and astrocytes. These GPCs are upregulated following traumatic or demyelinating lesions, followed by their differentiation into oligodendrocytes. However, this innate response does not adequately promote remyelination. As a result, researchers have been focusing their efforts on harvesting, culturing, characterizing, and transplanting GPCs into injured regions of the adult mammalian CNS in a variety of animal models of CNS trauma or demyelinating disease. The technical and logistic considerations for transplanting GPCs are extensive and crucial for optimizing and maintaining cell survival before and after transplantation, promoting myelination, and tracking the fate of transplanted cells. This is especially true in trials of GPC transplantation in combination with other strategies such as neutralization of inhibitors to axonal regeneration or remyelination. Overall, such studies improve our understanding and approach to developing clinically relevant therapies for axonal remyelination following traumatic brain injury (TBI) or spinal cord injury (SCI) and demyelinating diseases such as MS.  相似文献   
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