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排序方式: 共有647条查询结果,搜索用时 15 毫秒
641.
Elham Khodaverdi Farnaz Sadat Mirzazadeh Tekie Farzin Hadizadeh Haydar Esmaeel Seyed Ahmad Mohajeri Sayyed A. Sajadi Tabassi Gholamhossein Zohuri 《AAPS PharmSciTech》2014,15(1):177-188
Although conventional pharmaceuticals have many drug dosage forms on the market, the development of new therapeutic molecules and the low efficacy of instant release formulations for the treatment of some chronic diseases and specific conditions encourage scientists to invent different delivery systems. To this purpose, a supramolecular hydrogel consisting of the tri-block copolymer PLGA-PEG-PLGA and α-cyclodextrin was fabricated for the first time and characterised in terms of rheological, morphological, and structural properties. Naltrexone hydrochloride and vitamin B12 were loaded, and their release profiles were determined. 相似文献
642.
Elham Aslankoohi Karin Voordeckers Hong Sun Aminael Sanchez-Rodriguez Elisa van der Zande Kathleen Marchal Kevin J. Verstrepen 《Nucleic acids research》2012,40(19):9506-9512
Genetic transformation is a natural process during which foreign DNA enters a cell and integrates into the genome. Apart from its relevance for horizontal gene transfer in nature, transformation is also the cornerstone of today''s recombinant gene technology. Despite its importance, relatively little is known about the factors that determine transformation efficiency. We hypothesize that differences in DNA accessibility associated with nucleosome positioning may affect local transformation efficiency. We investigated the landscape of transformation efficiency at various positions in the Saccharomyces cerevisiae genome and correlated these measurements with nucleosome positioning. We find that transformation efficiency shows a highly significant inverse correlation with relative nucleosome density. This correlation was lost when the nucleosome pattern, but not the underlying sequence was changed. Together, our results demonstrate a novel role for nucleosomes and also allow researchers to predict transformation efficiency of a target region and select spots in the genome that are likely to yield higher transformation efficiency. 相似文献
643.
Ebrahimi Elham Shabestari Rima Manafi Bashash Davood Safa Majid 《Molecular biology reports》2022,49(3):2025-2036
Molecular Biology Reports - Myeloid cell leukemia-1 (MCL-1) is a component of the Bcl-2 anti-apoptotic family that plays a key role in cell proliferation and differentiation. Despite tremendous... 相似文献
644.
Kazem Mashayekhi Mojtaba Sankian Saeed Mohammadian Haftcheshmeh Ramezan Ali Taheri Kazem Hassanpour Gholamreza Farnoosh 《Biotechnology progress》2021,37(5):e3191
To increase the efficiency of aptamers to their targets, a simple and novel method has been developed based on aptamer oligomerization. To this purpose, previously anti-human TNF-α aptamer named T1–T4 was trimerized through a trimethyl aconitate core for neutralization of in vitro and in vivo of TNF-α. At first, 54 mer T1–T4 aptamers with 5′-NH2 groups were covalently coupled to three ester residues in the trimethyl aconitate. In vitro activity of novel anti-TNF-α aptamer and its dissociation constant (Kd) was done using the L929 cell cytotoxicity assay. In vivo anti-TNF-α activity of new oligomerized aptamer was assessed in a mouse model of cutaneous Shwartzman. Anchoring of three T1–T4 aptamers to trimethyl aconitate substituent results in formation of the 162 mer fragment, which was well revealed by gel electrophoresis. In vitro study indicated that the trimerization of T1–T4 aptamer significantly improved its anti-TNF-α activity compared to non-modified aptamers (P < 0.0001) from 40% to 60%. The determination of Kd showed that trimerization could effectively enhance Kd of aptamer from 67 nM to 36 nM. In vivo study showed that trimer aptamer markedly reduced mean scar size from 15.2 ± 1.2 mm to 1.6 ± 0.1 mm (P < 0.0001), which prevent the formation of skin lesions. In vitro and in vivo studies indicate that trimerization of anti-TNF-α aptamer with a novel approach could improve the anti-TNF-α activity and therapeutic efficacy. According to our findings, a new anti-TNF-α aptamer described here could be considered an appropriate therapeutic agent in treating several inflammatory diseases. 相似文献
645.
Taheri Serpil Karaca Zuleyha Rassoulzadegan Minoo Mehmetbeyoglu Ecmel Zararsiz Gokmen Sener Elif Funda Bayram Kezban Korkmaz Tufan Esra Sahin Mustafa Caglar Marasli Mert Kahraman Memis Mehmet Canatan Halit Ozturk Figen Tanriverdi Fatih Unluhizarci Kursad Kelestimur Fahrettin 《Cellular and molecular neurobiology》2022,42(5):1523-1542
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647.
Herein, we make an effort to enhance the antimicrobial activity of levofloxacin (LVX) antibiotic via conjugation to a cell‐penetrating peptide (CPP) including Cys‐Gly‐Ala‐Phe‐Pro‐His‐Arg. For this purpose, cysteine is used as a linker between the LVX and CPP chain, and two heterogeneous nanoscale catalytic systems are employed as the substantial alternatives for traditional peptide coupling reagents like N,N,N′,N′‐tetramethyl‐O‐(benzotriazol‐1‐yl)uronium tetrafluoroborate (TBTU). Briefly, it has been found out that the antimicrobial potency of the synthesized CPP‐LVX conjugate (on the gram‐positive and gram‐negative bacteria) is noticeably enhanced (~20% more). It has been revealed via zone of inhibition (ZOI) and optical density (OD) evaluations. As a convenient method for making this type of the effective conjugations, ultrasound waves (with a specific frequency and power density) activate the catalytic sites of the heterogeneous nanoparticles. Through this synergistic effect, peptide/amide bond is formed during a short time (10 min), and high reaction yield (>90%) is obtained under mild conditions. Moreover, as a simple purification process, the catalyst nanoparticles are collected and separated through their high magnetic property. 相似文献