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21.
Helena Kratochvílov Milo Mrz Barbora J. Kasperov Daniel Hlav
ek Jakub Mahrík Ivana Lakov Anna Cinkajzlov Zdenk Matloch Zdeka Lacinov Jaroslava Trnovsk Peter Ivk Peter Novodvorský Ivan Netuka Martin Haluzík 《International journal of molecular sciences》2021,22(9)
The aim of our study was to analyze mitochondrial and endoplasmic reticulum (ER) gene expression profiles in subcutaneous (SAT) and epicardial (EAT) adipose tissue, skeletal muscle, and myocardium in patients with and without CAD undergoing elective cardiac surgery. Thirty-eight patients, 27 with (CAD group) and 11 without CAD (noCAD group), undergoing coronary artery bypass grafting and/or valvular surgery were included in the study. EAT, SAT, intercostal skeletal muscle, and right atrium tissue and blood samples were collected at the start and end of surgery; mRNA expression of selected mitochondrial and ER stress genes was assessed using qRT-PCR. The presence of CAD was associated with decreased mRNA expression of most of the investigated mitochondrial respiratory chain genes in EAT, while no such changes were seen in SAT or other tissues. In contrast, the expression of ER stress genes did not differ between the CAD and noCAD groups in almost any tissue. Cardiac surgery further augmented mitochondrial dysfunction in EAT. In our study, CAD was associated with decreased expression of mitochondrial, but not endoplasmic reticulum stress genes in EAT. These changes may contribute to the acceleration of coronary atherosclerosis. 相似文献
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Evaluation of Floxuridine Oligonucleotide Conjugates Carrying Potential Enhancers of Cellular Uptake
Anna Avi Anna Clua Maria Jos Bleda Ramon Eritja Carme Fbrega 《International journal of molecular sciences》2021,22(11)
Conjugation of small molecules such as lipids or receptor ligands to anti-cancer drugs has been used to improve their pharmacological properties. In this work, we studied the biological effects of several small-molecule enhancers into a short oligonucleotide made of five floxuridine units. Specifically, we studied adding cholesterol, palmitic acid, polyethyleneglycol (PEG 1000), folic acid and triantennary N-acetylgalactosamine (GalNAc) as potential enhancers of cellular uptake. As expected, all these molecules increased the internalization efficiency with different degrees depending on the cell line. The conjugates showed antiproliferative activity due to their metabolic activation by nuclease degradation generating floxuridine monophosphate. The cytotoxicity and apoptosis assays showed an increase in the anti-cancer activity of the conjugates related to the floxuridine oligomer, but this effect did not correlate with the internalization results. Palmitic and folic acid conjugates provide the highest antiproliferative activity without having the highest internalization results. On the contrary, cholesterol oligomers that were the best-internalized oligomers had poor antiproliferative activity, even worse than the unmodified floxuridine oligomer. Especially relevant is the effect induced by palmitic and folic acid derivatives generating the most active drugs. These results are of special interest for delivering other therapeutic oligonucleotides. 相似文献
24.
Shuya Liang Miaomiao Wang Jun Wang Guanzhi Chen 《Chembiochem : a European journal of chemical biology》2021,22(22):3184-3189
To overcome high toxicity, low bioavailability and poor water solubility of chemotherapeutics, a variety of drug carriers have been designed. However, most carriers are severely limited by low drug loading capacity and adverse side effects. Here, a new type of metal-drug nanoparticles (MDNs) was designed and synthesized. The MDNs self-assembled with Fe(III) ions and drug molecules through coordination, resulting in nanoparticles with high drug loading. To assist systemic delivery and prolong circulation time, the obtained MDNs were camouflaged with red blood cell (RBCs) membranes (RBCs@Fe-DOX MDNs) to improve their stability and dispersity. The RBCs@Fe-DOX MDNs presented pH-responsive release functionalities, resulting in drug release accelerated in acidic tumor microenvironments. The outstanding in vitro and in vivo antitumor therapeutic outcome was realized by RBCs@Fe-DOX MDNs. This study provides an innovative design guideline for chemotherapy and demonstrates the great capacity of nanomaterials in anticancer treatments. 相似文献
25.
Dongming Hu Radovan Kovacevic 《International Journal of Machine Tools and Manufacture》2003,43(1):419
Laser-Based Additive Manufacturing (LBAM) is a promising manufacturing technology that can be widely applied to part preparation, surface modification, and Solid Freeform Fabrication (SFF). A large number of parameters govern the LBAM process. These parameters are sensitive to the environmental variations, and they also influence each other. This paper introduces the research work in RCAM on improving the performance of the LBAM process. Metal powder delivery real-time sensing and control is studied to achieve a controllable powder delivery for fabrication of functionally graded material. A closed-loop control system based on infrared image sensing is built for control of the heat input and size of the molten pool in the LBAM process. The closed-loop control results show a great improvement in the geometrical accuracy of the built features. A three-dimensional finite element model is also established to explore the thermal behavior of the molten pool in the closed-loop controlled LBAM process. 相似文献
26.
《Expert systems with applications》2014,41(6):2947-2956
To enable the immediate and efficient dispatch of relief to victims of disaster, this study proposes a greedy-search-based, multi-objective, genetic algorithm capable of regulating the distribution of available resources and automatically generating a variety of feasible emergency logistics schedules for decision-makers. The proposed algorithm dynamically adjusts distribution schedules from various supply points according to the requirements at demand points in order to minimize unsatisfied demand for resources, time to delivery, and transportation costs. The proposed algorithm was applied to the case of the Chi–Chi earthquake in Taiwan to verify its performance. Simulation results demonstrate that under conditions of a limited/unlimited number of available vehicles, the proposed algorithm outperforms the MOGA and standard greedy algorithm in ‘time to delivery’ by an average of 63.57% and 46.15%, respectively, based on 10,000 iterations. 相似文献
27.
The high melting point of poly(1,4‐cyclohexanedicarboxylic anhydride) [poly(CHDA)] is a disadvantage, in that it is intractable in the melting process of a drug delivery system. This report relates to diols introduced into the polyanhydride main chain to decrease its melting point. Various poly(ester anhydride)s containing ethylene glycol, 1,3‐propanediol, 1,4‐butanediol, or 1,6‐hexandiol [poly(CHDA–XDO)] were synthesized by the esterification reaction and melt polycondensation. FTIR, DSC, WAXD, and intrinsic viscosity of polymers were recorded and hydrolytic degradation, as well as in vitro drug delivery, was conducted. The results show that the samples are stable in an anhydrous environment at room temperature and degrade in water following a surface erosion mechanism. The degradation period of poly(CHDA–XDO) ranged from 130 to 320 h as a result of the different diols and amounts of XDO introduced. The in vitro drug delivery gave 130–350 h of stable delivery along with the typical surface erosion mechanism. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2509–2514, 2002 相似文献
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29.
中国人丙型肝炎病毒全长NS3基因的克隆、序列分析及表达 总被引:1,自引:0,他引:1
目的 为改进HCV试剂的质量克隆 1b型丙型肝炎病毒 (HCV)全长NS3基因并在原核细胞中表达。方法 用RT PCR方法从中国人血清中扩增全长NS3片段 ,进行序列分析 ,并克隆到pET3 0a(+)原核表达载体中 ,构建的原核表达载体pET NS3 180 0在大肠杆菌BL2 1(DE3 )中表达 ,用Westernblot方法进行验证。结果 扩增到 1b型HCV全长NS3片段 ,经Westernblot实验表明该片段具有抗原活性。结论 构建的质粒可在大肠杆菌中表达完整的NS3蛋白 相似文献
30.
Markland William; Pollock Daniel; Livingston David J. 《Protein engineering, design & selection : PEDS》1989,3(2):111-116
The interactions between tPA domains that are important forcatalysis are poorly understood. We have probed the functionof interdomain interactions by generating tPA variants in whichdomains are duplicated or rearranged. The proteins were expressedin a transient mammalian expression system and tested in vitrofor their ability to activate plasminogen, induce fibrinolysisand bind to a forming fibrin clot. Duplication of the heavychain domains of tPA produced enzymatically active tPA variants,many of which demonstrated similar in vitro amidolytic and fibrinolyticactivity and similar fibrin affinity to the parent molecule.Zymographic analysis of the domain duplication tPA variantsshowed one major active species for each variant. Selectionof the residues duplicated and the interdomain spacing werefound to be critical considerations in the design of tPA variantswith duplicated domains. We also rearranged the domains of tPAsuch that kringle 1 replaced the second kringle domain and viceversa. An analysis of these variants indicates that the firstkringle domain can confer fibrin affinity to a tPA variant andfunction in place of kringle 2. Therefore, in wild-type tPA,the functions of kringle 1 and kringle 2 must be dependent partiallyon their orientation within the heavy chain of the protein.The functional autonomy of the heavy and light chains of tPAis demonstrated by the activity of a tPA variant in which theorder of the heavy and light chains was reversed. 相似文献