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211.
Maral Nouri Hajbaba Mehrab Pourmadadi Fatemeh Yazdian Hamid Rashedi Majid Abdouss Dina Sadat Zhohrabi 《Biotechnology progress》2023,39(1):e3305
In recent decades, magnetic nanoparticles modified with biocompatible polymers have been recognized as a suitable tool for treating breast cancer. The aim of this research was to evaluate the function of chitosan/agarose-functionalized Fe2O3 nanoparticles on the MCF-7 breast cancer cell line and the expression of BCL2 and BAX genes. Free Fe2O3 nanoparticles were prepared by hydrothermal method. FTIR, XRD, SEM, DLS, VSM, and zeta potential analyses determined the size and morphological characteristics of the synthesized nanoparticles. The effect of Fe2O3 free nanoparticles and formulated Fe2O3 nanoparticles on induction of apoptosis was studied by double-dye Annexin V-FITC and PI. Also, the gene expression results using the PCR method displayed that Fe2O3 formulated nanoparticles induced BAX apoptosis by increasing the anti-apoptotic gene expression and decreasing the expression of pro-apoptotic gene BCL2, so the cell progresses to planned cell death. In addition, the results showed that the BAX/BCL2 ratio decreased significantly after treatment of MCF-7 cells with free Fe2O3 nanoparticles, and the BAX/BCL2 ratio for Fe2O3 formulated nanoparticles increased significantly. Also, to evaluate cell migration, the scratch test was performed, which showed a decrease in motility of MCF-7 cancer cells treated with Fe2O3 nanoparticles formulated with chitosan/agarose at concentrations of 10, 50, 100, and 200 μg/ml. 相似文献
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213.
Olivier Rannou Emmanuelle Le Chatelier Marilynn A. Larson Hamid Nouri Bérengère Dalmais Charles Laughton Laurent Jannière Panos Soultanas 《Nucleic acids research》2013,41(10):5303-5320
Bacillus subtilis has two replicative DNA polymerases. PolC is a processive high-fidelity replicative polymerase, while the error-prone DnaEBs extends RNA primers before hand-off to PolC at the lagging strand. We show that DnaEBs interacts with the replicative helicase DnaC and primase DnaG in a ternary complex. We characterize their activities and analyse the functional significance of their interactions using primase, helicase and primer extension assays, and a ‘stripped down’ reconstituted coupled assay to investigate the coordinated displacement of the parental duplex DNA at a replication fork, synthesis of RNA primers along the lagging strand and hand-off to DnaEBs. The DnaG–DnaEBs hand-off takes place after de novo polymerization of only two ribonucleotides by DnaG, and does not require other replication proteins. Furthermore, the fidelity of DnaEBs is improved by DnaC and DnaG, likely via allosteric effects induced by direct protein–protein interactions that lower the efficiency of nucleotide mis-incorporations and/or the efficiency of extension of mis-aligned primers in the catalytic site of DnaEBs. We conclude that de novo RNA primer synthesis by DnaG and initial primer extension by DnaEBs are carried out by a lagging strand–specific subcomplex comprising DnaG, DnaEBs and DnaC, which stimulates chromosomal replication with enhanced fidelity. 相似文献
214.