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Fatima Hamdan Zahra Bigdeli Dr. S. Mohsen Asghari Dr. Afsaneh Sadremomtaz Prof. Saeed Balalaie 《ChemMedChem》2019,14(2):282-288
Arg-Gly-Asp (RGD) peptides represent the most outstanding recognition motif involved in cell adhesion that binds to the αvβ3 integrin, which has been targeted for cancer therapy. Various RGD-containing peptides and peptidomimetics have been designed and synthesized to selectively inhibit this integrin. In this study, the synthesis of RGD-based peptides through the incorporation of the short bioactive peptide Phe-Ala-Lys-Leu-Phe (FAKLF) at the C and N termini of RGD has been achieved by using a solid-phase peptide synthesis approach. The peptides were purified by means of preparative RP-HPLC and their structures were confirmed through HRMS (ESI). The MTT assay revealed that the RGD and FAKLF peptides inhibited the proliferation of human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner, with IC50 values of 3000 and 500 ng mL−1, respectively. Interestingly, a drastic improvement was observed in the antiproliferative activity of the combined structures of the FAKLFRGD and RGDFAKLF peptides, leading to IC50 values of 200 and 136.7 ng mL−1, respectively. Meanwhile, based on apoptosis results, the potential of peptides to induce apoptosis, in accordance with their antiproliferative activity, indicated that the RGD and FAKLF peptides, and the peptides synthesized based on their combinations induced cell apoptosis in a dose-dependent manner followed by inhibition of the proliferation of endothelial cells. Moreover, the incorporation of d -leucine increased the induction of apoptosis by these peptides. 相似文献
74.
The mono-metallic and bi-metallic catalysts have been prepared by impregnating with solutions containing a compound of H2PtCl6, WO3 and 1 ml HCl (0.1 mol). It should be noted that the catalysts’ activity and selectivity have been determined under these
conditions: 450–500°C, and 15–25 atm by H2. For converting n-heptane, the molar ratio H2/C7H16 is 5, and LHSV is 1.5 ml/h. It has been proved that, under these experimental conditions, the conversion of n-heptane into
branched aliphatic isomers is catalyzed by a bifunctional mechanism. The results indicate that in the presence of W, the catalysts
have much higher selectivity and stability for isomerization reaction. At a given conversion, the bi-metallic catalysts produce
much lower concentrations of cracked products. According to the tests, W modifies the support acidity resulting to the higher
selectivity for isomerization and the lower one for cracking, and it also modifies the Pt properties. 相似文献
75.
In this article we present a two‐stage Ku‐band low‐noise amplifier (LNA) using discrete pHEMT transistors on non‐PTFE substrates for low‐cost direct broadcast satellite (DBS) phased‐array systems (patent pending). The vertical input configuration of the LNA lends itself to direct integration with input port of antenna modules of the phased array, which minimizes preamplification losses. DC decoupling between LNA stages is realized using interdigital microstrip capacitors such that the implementation reduces the number of discrete microwave components and thereby not only reduces the component and assembly costs but also decreases the standard deviation of such crucial parameters of phased‐array systems as the end‐to‐end phase shift of the amplifier and the amplifier gain. Using the proposed printed decoupling capacitors, a cost reduction better than 30% of the original costs has been achieved. Additionally, we present a hybrid design procedure for the complete LNA, including its input and output connectors as well as packaging effects. This method is not based on parameter extraction, but encompasses electromagnetic (EM) field simulator results which are further combined using a high‐level circuit simulator. According to the presented measurement results, the implemented Ku‐band LNA has a noise figure better than 0.9 dB and a gain higher than 20 dB with a gain flatness of 0.3 dB over a 5% bandwidth. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2006. 相似文献
76.
Rasooli Ali Safavi Mir Saman Ahmadiyeh Somayeh Jalali Akram 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(2):320-327
Protection of Metals and Physical Chemistry of Surfaces - The goal of the present investigation is to evaluate the influences of plating parameters such as TiO2 nanoparticles concentration in the... 相似文献
77.
Hassan Karimi-Maleh Mahbobeh Moazampour Mehdi Yoosefian Afsaneh L. Sanati Fahimeh Tahernejad-Javazmi Mohamad Mahani 《Food Analytical Methods》2014,7(10):2169-2176
In this work, we describe application of a high-sensitive electrochemical sensor for determination of ascorbic acid (AA) in the presence of high concentration of Sudan I in food samples. In the first step, we study synthesis and characterization of NiO/NPs with X-ray diffraction (XRD) method. In the second step, application of NiO/NPs describe in the preparation of carbon-paste electrode modified with (9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)-4-ethylbenzene-1,2-diol (DEDED) as a high-sensitive and selective voltammetric sensor for determination of AA and Sudan I. The electrocatalytic oxidation of AA at the modified electrode was investigated by cyclic voltammetry, chronoamperometry and square wave voltammetry (SWV). For the mixture containing AA and Sudan I, the peaks potential was well separated from each other. Their square wave voltammetrics peaks current increased linearly with their concentration at the ranges of 0.01–600 and 0.5–1,000 μM, with the detection limits of 0.006 and 0.2 μM, respectively. Finally, the proposed method was also examined as a selective, simple, and precise electrochemical sensor for the determination of AA and Sudan I in real samples such as fruit juices, fresh vegetable juice, chilli sauce and tomato sauce. 相似文献
78.
Golmohammadi Mohammad H. Safavi Hamid R. Sandoval-Solis Samuel Fooladi Mahmood 《Water Resources Management》2021,35(2):593-611
Water Resources Management - Reliability, resilience, and vulnerability (RRV) have been widely used as the performance criteria of a water supply system in the studies conducted over the last three... 相似文献
79.
Majidi Mir Reza Pournaghi-Azar Mohammad Hossein Saadatirad Afsaneh Alipour Esmaeel 《Food Analytical Methods》2015,8(4):1067-1077
Food Analytical Methods - This paper describes the use of a pencil lead electrode (PLE) covered by hemoglobin (Hb) through a simple and rapid electroless method for the electroreduction of hydrogen... 相似文献
80.
Application of Taguchi method in optimization of desalination by vacuum membrane distillation 总被引:1,自引:0,他引:1
This research focuses on desalination via vacuum membrane distillation (VMD). In order to enhance the performance of VMD in desalination and to get more flux, effects of operating parameters on the yield of distillate water were studied. Four parameters at three levels were selected: temperature (35, 45, and 55 °C), vacuum pressure (30, 80, and 130 mbar), flow rate (15, 30, and 60 mL/s) and concentration (50, 100, and 150 g/L). Taguchi method was used to plan a minimum number of experiments. The optimal levels thus determined for the four factors were: temperature 55 °C, vacuum pressure 30 mbar, flow rate 30 mL/s and concentration 50 g/L. The results show that increasing temperature and decreasing vacuum pressure improve permeate flux. However, the permeate flux increases with increasing flow rate initially and then reaches to a maximum value at 30 mL/s and then decreases with increasing the flow rate. 相似文献