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921.
Fatemeh Firouzi Amoodizaj Sevda Baghaeifar Elham Taheri Mahdieh Farhoudi Sefidan Jadid Maryam Safi Nasrin Seyyed Sani Saba Hajazimian Alireza Isazadeh Dariush Shanehbandi 《Journal of biochemical and molecular toxicology》2020,34(6)
Gastric cancer (GC) is one of the prevalent human malignancies and the third most common cause of cancer‐related death worldwide. The doxorubicin hydrochloride is one of the important chemotherapeutic anticancer agents, with a limited therapeutic efficacy for treatment of GC. Therefore, taking advantage of synergistic effects by strategies like combination therapy seems appropriate and promising in treatment of GC. The aim of this study was to investigate a novel method to enhance the therapeutic efficacy of doxorubicin (as a chemotherapeutic agent) by co‐administration of curcumin (as a bioactive herbal compound) in GC treatment. In the present study, the effects of curcumin, doxorubicin, and their combinations (Dox‐Cur) were evaluated on the viability, morphological features, tumor spheroid formation, migration, invasion, and apoptosis of gastric adenocarcinoma cell line (AGS). Moreover, expression levels of BAX, BCL‐2, and CASP9 genes were assessed among AGS cells treated with curcumin, doxorubicin, and Dox‐Cur. The obtained results showed that all of curcumin, doxorubicin, and Dox‐Cur treatments significantly decreased the viability, tumor spheroid formation, migration, and invasion in the GC model cells. Furthermore, apoptosis rates in AGS cells were increased in a concentration‐ and time‐dependent manner in all of the treatment groups. Moreover, the anticancer activity of the Dox‐Cur combination was significantly more than curcumin and doxorubicin treatments alone. According to the results, Dox‐Cur combination therapy exerts more profound apoptotic and anticancer effects on the AGS cell line than curcumin or doxorubicin monotherapy. 相似文献
922.
Mohammadi Saeed Oryan Shahrbanoo Komaki Alireza Eidi Akram Zarei Mohammad 《International journal of peptide research and therapeutics》2020,26(1):357-367
International Journal of Peptide Research and Therapeutics - Irisin is a soluble and exercise-induced myokine and/or adipokine hormone; generated by FNDC5 (a gene precursor) and also, it can... 相似文献
923.
Fateme Razazpour Fatemeh Gashtasbi Sima Shahabi Moshaverinia Alireza Hasannia Sadegh 《International journal of peptide research and therapeutics》2020,26(3):1629-1639
International Journal of Peptide Research and Therapeutics - One of the main challenges in oral disease is prevention of bacterial infections considering antibiotic resistance as a result of... 相似文献
924.
Elizabeth S. Elvington Alireza Salmanzadeh Mark A. Stremler Rafael V. Davalos 《Journal of visualized experiments : JoVE》2013,(79)
Dielectrophoresis (DEP) is the phenomenon by which polarized particles in a non-uniform electric field undergo translational motion, and can be used to direct the motion of microparticles in a surface marker-independent manner. Traditionally, DEP devices include planar metallic electrodes patterned in the sample channel. This approach can be expensive and requires a specialized cleanroom environment. Recently, a contact-free approach called contactless dielectrophoresis (cDEP) has been developed. This method utilizes the classic principle of DEP while avoiding direct contact between electrodes and sample by patterning fluidic electrodes and a sample channel from a single polydimethylsiloxane (PDMS) substrate, and has application as a rapid microfluidic strategy designed to sort and enrich microparticles. Unique to this method is that the electric field is generated via fluidic electrode channels containing a highly conductive fluid, which are separated from the sample channel by a thin insulating barrier. Because metal electrodes do not directly contact the sample, electrolysis, electrode delamination, and sample contamination are avoided. Additionally, this enables an inexpensive and simple fabrication process.cDEP is thus well-suited for manipulating sensitive biological particles. The dielectrophoretic force acting upon the particles depends not only upon spatial gradients of the electric field generated by customizable design of the device geometry, but the intrinsic biophysical properties of the cell. As such, cDEP is a label-free technique that avoids depending upon surface-expressed molecular biomarkers that may be variably expressed within a population, while still allowing characterization, enrichment, and sorting of bioparticles.Here, we demonstrate the basics of fabrication and experimentation using cDEP. We explain the simple preparation of a cDEP chip using soft lithography techniques. We discuss the experimental procedure for characterizing crossover frequency of a particle or cell, the frequency at which the dielectrophoretic force is zero. Finally, we demonstrate the use of this technique for sorting a mixture of ovarian cancer cells and fluorescing microspheres (beads). 相似文献
925.
926.
Behnam Honarvar Neda Odoomi Mohsen Moghadami Parvin Afsar Kazerooni Alireza Hassanabadi Parvin Zare Dolatabadi Ehsan Farzanfar Kamran Bagheri Lankarani 《PloS one》2013,8(12)
Objective
Iran has the highest rate of opiate use worldwide. However, most opiate users are not screened for hepatitis virus infections. This study aimed to provide accurate, detailed data on the size of the opiate user population at risk of developing these infections.Method
This seroprevalence study was conducted in the city of Shiraz, southern Iran. All participants were screened for HBV, HCV and HIV infection. The data were analyzed with SPSS.Result
Among 569 participants, 233 (40.9%) were injection drug users (IDU), 369 (64.8%) were heterosexual, 84 (14.7%) were bisexual and 15 (2.6%) were homosexual. One hundred nine (19.1%) were HCV antibody-positive, 18 (3.1%) were HBS antigen-positive, 72 (12.6%) were HBc antibody-positive and 23 (4%) were HIV-positive. Among IDU compared to non-IDU, positivity rates for HBS antigen (5.5 vs 1.4%), HBc antibody (22.7 vs 5.6%), HCV antibody (40.3 vs 4.4%) and HIV (7.7 vs 1.4%) were higher (P < 0.05). Most patients with HBV (80.7%) and HCV infection (83.4%) were HIV-negative. In the cumulative analysis, only history of imprisonment was a statistically significant determinant of infection by HCV or HBV in opiate users.Conclusion
The current policy of screening only HIV-positive drug users for HBV and HCV in Iran misses most cases of HBV and HCV infection. We therefore recommend urgent revision of the nationwide protocol by the Ministry of Health in Iran to implement routine screening of all opiate users and especially IDU for these viruses, regardless of their HIV status. 相似文献927.
Alireza Najafi Chermhini Mostafa Abedi Hossein Farrokhpour Abbas Teimouri Bahareh Reisi 《Journal of molecular modeling》2013,19(10):4377-4386
The tautomerism of all possible forms of tetrazole selenone (A–G), induced by proton transfer, was studied, theoretically, in different environments including gas phase, continuum solvent and microsolvated environment with one or two explicit water or ammonia molecules. The calculations were performed using two different levels of theory including mPW2PLYP and DFT-B3LYP. The 6-311++G(d,p) basis set was used for C, H, O and N and the standard relativistic effective core pseudo potential LANL2DZ basis set was used for Se atom. It was found that the tetrazole selenone, in the form of A, is the most stable isomer in all of the environments considered in this work. The kinetics of proton transfer reaction was studied in both gas and solvent environments and it was concluded that the activation energy of the reaction increases with going from the gas phase to polar solvents. Moreover, the proton transfer reaction assisted by one or two water or ammonia molecules was investigated and it was found that the activation energy significantly reduces. 相似文献
928.
Transposable elements are found in the genomes of all eukaryotes and play a critical role in altering gene expression and genome organization. In Drosophila melanogaster, transposable P elements are responsible for the phenomenon of hybrid dysgenesis. KP elements, a deletion-derivative of the complete P element, can suppress this mutagenic effect. KP elements can also silence the expression of certain other P-element-mediated transgenes in a process called P-element-dependent silencing (PDS), which is thought to involve the recruitment of heterochromatin proteins. To explore the mechanism of this silencing, we have mobilized KP elements to create a series of strains that contain single, well-defined KP insertions that show PDS. To understand the quantitative role of KP elements in PDS, these single inserts were combined in a series of crosses to obtain genotypes with zero, one, or two KP elements, from which we could examine the effect of KP gene dose. The extent of PDS in these genotypes was shown to be dose dependent in a logarithmic rather than linear fashion. A logarithmic dose dependency is consistent with the KP products interacting with heterochromatic proteins in a concentration-dependent manner such that two molecules are needed to induce gene silencing. 相似文献
929.
Manichaikul A Wang Q Shi YL Zhang Z Leitinger N Shi W 《American journal of physiology. Heart and circulatory physiology》2011,301(3):H1056-H1061
Ath29 is an atherosclerosis susceptibility locus on chromosome 9 identified in an intercross between C57BL/6 (B6) and C3H/HeJ (C3H) apolipoprotein E-deficient (apoE(-/-)) mice. This locus was subsequently replicated in two separate intercrosses that developed early or advanced atherosclerotic lesions. The objective of this study was to characterize Ath29 through construction and analysis of a congenic strain and identify underlying candidate genes. A congenic line was constructed by introgressing the chromosomal segment harboring Ath29 from C3H.apoE(-/-) into B6.apoE(-/-) mice. Congenic mice developed significantly smaller early and advance atherosclerotic lesions than B6.apoE(-/-) mice. Microarray analysis revealed 317 genes to be differentially expressed in the aorta of congenic mice compared with B6.apoE(-/-) mice. Pathway analysis of these genes suggested the Ca(2+) signaling pathway to be implicated in regulating atherosclerosis susceptibility. Rcn2 is located underneath the linkage peak of Ath29 and involved in Ca(2+) signaling. Multiple single-nucleotide polymorphisms between B6 and C3H mice were detected within and surrounding Rcn2 with one single-nucleotide polymorphism falling within an upstream cAMP response element. Immunostaining demonstrated its expression in atherosclerotic lesions. Knockdown of Rcn2 with small interfering RNAs resulted in significant reductions in both baseline and oxidized phospholipid-induced VCAM-1 and monocyte chemoattractant protein-1 expression by endothelial cells. Ath29 is confirmed to be a major atherosclerosis susceptibility locus affecting both early and advanced lesion formation in mice, and Rcn2 is identified as a novel regulator of cytokine expression. 相似文献
930.
Strojan P Aničin A Svetic B Šmid L Kos J 《The International journal of biological markers》2011,26(4):247-254
The hypothesis was tested that a specific pattern in the cysteine cathepsin/inhibitor ratio is associated with the development of more aggressive tumor cell phenotypes in squamous cell carcinoma of the head and neck (SCCHN). For this purpose commercially available ELISAs were used to determine the concentrations of cysteine cathepsins B and L and their inhibitors, stefins A and B, in cytosols of nontumorous mucosa and primary tumors from 92 patients. Using the stefin A concentration difference in matched pairs of tissue samples as a stratifying variable, 53 cases were found to be upregulated (higher concentrations in tumor samples than in nontumorous mucosa) and 39 cases downregulated. Disease recurrence was more frequent in the downregulated group than in the upregulated group (35.9% vs 11.3%, p=0.009), which resulted in significantly different 5-year disease-free survival rates (61.2% vs 88%, p=0.004). The consistency of these results was confirmed by repeating the analysis in an independent group of patients (the reference group). The presented results suggest that in patients with SCCHN, specific patterns in the proteolytic profile of cysteine proteases and their inhibitors are associated with the development of distinctly aggressive tumor cell phenotypes and are of prognostic value. 相似文献