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961.
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   
962.
Nucleic acid immunization has recently exhibited a great promise for immunotherapy of various diseases. However, it is now clear that powerful strategies are imminently needed to improve their efficiency. In this regard, whole bacteriophage particles have been described as efficient DNA vaccine delivery vehicles, capable of circumventing the limitations of naked DNA immunization. Moreover, phage particles could be engineered to display specific peptides on their surfaces. Given these inherent characteristics of phages, we have designed a novel hybrid phage-DNA immunization vector using both M13 and pAAV plasmid elements. Following the construction and in vitro confirmation of the designed vectors, they were used for comparative mice immunization, carrying the same DNA sequence. The results indicated the efficacy of the designed hybrid phage particles, to elicit higher humoral immunity, in comparison to conventional DNA-immunization vectors (pCI). In light of these findings, it could be concluded that using adeno-associated virus (AAV) expression cassette along with displaying TAT peptide on the surface of the phage particle could be deemed as an appealing strategy to enhance the DNA-immunization and vaccination efficacy.  相似文献   
963.
Due to the importance of soluble nanotubes in biological systems, computational research on DNA base functionalized nanotubes is of interest. This study presents the quantitative results of Monte Carlo simulations of Li-doped silicon carbide nanotubes and its nucleic acid base complexes in water. Each species was first modeled by quantum mechanical calculations and then Monte Carlo simulations were applied to study their properties in aqueous solution. Solvation free energies were computed to indicate the solvation behavior of these compounds. The computations show that solvation free energies of the complexes of DNA bases with Li-doped SiC nanotubes are in the order: thymine > cytosine > adenine > guanine. The results of complexation free energies were also used to study the stability of related structures, which indicate that thymine-Li-doped SiC nanotubes produce the most stable compound among the four DNA base complexes.  相似文献   
964.
965.
Insulin secretion tests were carried out before and after treatment in patients with severe congestive heart failure. Before treatment the plasma insulin level and the insulin secretion response to intravenous tolbutamide were significantly reduced in all patients. In patients who made a good clinical recovery the plasma insulin level and the insulin secretion response were significantly improved. Patients who had a poor response to medical treatment showed little improvement in their insulin secretion test. This suppression of insulin secretion is probably due to the reduced blood flow to the pancreas together with a high level of circulating catecholamines.  相似文献   
966.
Molecular Biology Reports - The miRNAs have been shown to be involved in breast cancer. The aim of the present research was to evaluate the impacts of extract from Euphorbia szovitsii Fisch...  相似文献   
967.
A sample of used, highly saline diesel invert drilling mud (DIDM), artificially contaminated with lead, was tested for remediation using ICPET/ NRC's Solvent Extraction Soil Remediation (SESR) process. The work comprised investigation of the concurrent solvent extraction of diesel oil and fixation of lead by co-agglomeration of metal binding agents. Peat, soluble and insoluble phosphates, coal combustion fly ashes, and flue gas desulfurization scrubber sludge were tested as lead fixation agents. Virtually complete extraction of diesel oil was achieved in a five-step extraction process using toluene, trichloroethylene, or hexane as solvents. The effect of the metal fixation agents on solvent extraction efficiency was also investigated. After remediation to remove hydrocarbons and fix heavy metals, the DIDM sample remained saline. Successful leaching of brine from the dried agglomerates was accomplished by water percolation through a fixed bed of the dried, agglomerated soil. The cleaned DIDM was evaluated for resistance to acid leaching of lead using the U.S.-EPA's toxicity test method 1310A and Toxicity Characteristics Leaching Procedure method 1311. Long-term stability of the treated solids to acid leaching was tested using the U.S.EPA's multiple extraction procedure method 1320. Bioavailability of fixed lead to barley plants grown on synthetic soils prepared from remediated DIDM was determined by analyzing the roots and shoots for lead content. Acid phosphatase, peroxidase, and protein levels were determined in plant roots and soil leachates by biochemical analysis methods. These results were used to assess the effect of enzymes produced by plant root systems, or soil associated microorganisms, on the stability of fixed lead. The presence of fixation agents reduced the bioavailability of lead to the plants.  相似文献   
968.
Transvenous pacemaker implantation tends to be difficult in the setting of a persistent left superior vena cava (SVC) and an absent or inaccessible right SVC. We report two small children in whom transvenous pacing leads were successfully inserted via a persistent left SVC. This technique was safe in our cases; however, favorable long-term result has yet to be demonstrated.  相似文献   
969.
In late December 2019 in Wuhan, China, several patients with viral pneumonia were identified as 2019 novel coronavirus (2019-nCoV). So far, there are no specific treatments for patients with coronavirus disease-19 (COVID-19), and the treatments available today are based on previous experience with similar viruses such as severe acute respiratory syndrome-related coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and Influenza virus. In this article, we have tried to reach a therapeutic window of drugs available to patients with COVID-19. Cathepsin L is required for entry of the 2019-nCoV virus into the cell as target teicoplanin inhibits virus replication. Angiotensin-converting-enzyme 2 (ACE2) in soluble form as a recombinant protein can prevent the spread of coronavirus by restricting binding and entry. In patients with COVID-19, hydroxychloroquine decreases the inflammatory response and cytokine storm, but overdose causes toxicity and mortality. Neuraminidase inhibitors such as oseltamivir, peramivir, and zanamivir are invalid for 2019-nCoV and are not recommended for treatment but protease inhibitors such as lopinavir/ritonavir (LPV/r) inhibit the progression of MERS-CoV disease and can be useful for patients of COVID-19 and, in combination with Arbidol, has a direct antiviral effect on early replication of SARS-CoV. Ribavirin reduces hemoglobin concentrations in respiratory patients, and remdesivir improves respiratory symptoms. Use of ribavirin in combination with LPV/r in patients with SARS-CoV reduces acute respiratory distress syndrome and mortality, which has a significant protective effect with the addition of corticosteroids. Favipiravir increases clinical recovery and reduces respiratory problems and has a stronger antiviral effect than LPV/r. currently, appropriate treatment for patients with COVID-19 is an ACE2 inhibitor and a clinical problem reducing agent such as favipiravir in addition to hydroxychloroquine and corticosteroids.  相似文献   
970.
The in vitro amplification of endothelial progenitor cells (EPCs) is an important method because of its role in gene transferring and regenerative medicine. In this study, we isolated rabbit bone marrow–derived EPCs to further manipulation and overexpression of dimethylarginine dimethylaminohydrolase (DDAH) in EPCs. Isolated EPCs were cultured, expanded in endothelial basal medium. Morphology of EPCs and expression levels of surface markers detected using immunocytochemistry staining and through the use of flow cytometery. Endothelial progenitor cells were transfected with plasmid vectors expressing human DDAH2 (DDAH2‐EPCs). Three days after gene transfer, positive transfected‐EPCs proliferation and DDAH activity were assayed. We observed colonies conformation and endothelium‐like morphology gradually in the third week of culture. Characterization results revealed positive expression of EPC surface markers CD106, Flk‐1, vWF, and CD34 using few identification techniques. Overexpression of DDAH2 increased citrulline production after 96 hours of transfection, 235.34 ± 0.69 vs 95.26 ± 5.76 ng/mL; P = .023. These results suggest that cell population with EPC characteristics can be simply isolated from rabbit bone marrow and successfully engineered to overexpress exogenous gene. In this study, we offer a feasible method to isolate and identify EPCs from bone marrow. In addition, an efficient transfection with a plasmid vector (without risk of interference) can be constructed a hybrid structure with EPC and DDAH2 gene to examine their function in vitro.  相似文献   
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