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Dysregulation of matrix metalloproteinases (MMPs) activity is known in many pathological conditions with which most of the conditions are related to elevate MMPs activities. Ficus deltoidea (FD) is a plant known for its therapeutic properties. In order to evaluate the therapeutic potential of FD leaf extract, we study the enzymatic inhibition properties of FD leaf extract and its major bioactive compounds (vitexin and isovitexin) on a panel of MMPs (MMP-2, MMP-8 and MMP-9) using experimental and computational approaches. FD leaf extract and its major bioactive compounds showed pronounced inhibition activity towards the MMPs tested. Computational docking analysis revealed that vitexin and isovitexin bind to the active site of the three tested MMPs. We also evaluated the cytotoxicity and cell migration inhibition activity of FD leaf extract in the endothelial EA.hy 926 cell line. Conclusively, this study provided additional information on the potential of FD leaf extract for therapeutical application.  相似文献   
2.
Based on Lagrangian multiplier method (LMM), the gain spectrum of distributed multi-pump Raman amplifier (DMRA) is optimized. Beside of governing rate equations in Raman amplifiers, we consider two applicable constrains on cost function for optimizing the gain spectrum. Because of more accurate and controllable designing of DMRAs, a maximum power for each input pump wave is considered as well as average gain value as two constrains. LMM reduces the optimization problem with constrains to solve a two-point boundary value problem for each solution. This method is applied to minimizing gain ripple of full bandwidth (60 nm) a 100 Km Raman amplifier for different number of pumps.  相似文献   
3.
Ficus deltoidea leaves extract are known to have good therapeutic properties such as antioxidant, anti-inflammatory and anti-diabetic. We showed that 50% ethanol-water extract of F. deltoidea leaves and its pungent compounds vitexin and isovitexin exhibited significant (p < 0.05) α-amylase inhibition with IC50 (vitexin: 4.6 μM [0.02 μg/mL]; isovitexin: 0.06 μg/mL [13.8 μM] and DPPH scavenging with IC50 (vitexin: 92.5 μM [0.4 μg/mL]; isovitexin: 0.5 μg/mL [115.4 μM]). Additionally, molecular docking analysis confirmed that vitexin has a higher binding affinity (-7.54 kcal/mol) towards α-amylase compared to isovitexin (?5.61 kcal/mol). On the other hand, the molecular dynamics findings showed that vitexin-α-amylase complex is more stable during the simulation of 20 ns when compared to the isovitexin-α-amylase complex. Our results suggest that vitexin is more potent and stable against α-amylase enzyme, thus it could develop as a therapeutic drug for the treatment of diabetes.  相似文献   
4.
The RF plasma discharge in liquid n-hexane is used to synthesize carbon nanoparticles. The results show that amorphous carbon nanoparticles with size of 5?C25?nm are the main product in the plasma in liquid n-hexane. Carbon nano-tubes of average diameter of 19?nm and length of 500?nm are also observed. The energy efficiency for carbon nanoparticles production is 2.9?mg/kJ which is more than 10 times larger than that of typical arc discharge synthesis method. The high speed observation indicates that the RF plasma in liquid has an alternating behaviour and it does not continuously emit light. The OES results show that H and C2 are the main observed species in the plasma. Based on the OES data, it is shown that plasma temperature is 4,030?K and the electron density is 2.54?×?1022?m?3. Our results suggest that this method can be considered as a new route for carbon nanostructures production.  相似文献   
5.
An efficient shooting method for fiber amplifiers and lasers   总被引:1,自引:0,他引:1  
A simple shooting method is proposed for the design of distributed multi-pumped Raman fiber amplifiers (RFAs) and Yb-doped double-clad fiber lasers (DCFLs). Using the proposed method a distributed RFA with 10 pump sources and 1700 mW total input pump power is simulated and high-power Yb-doped DCFL rate equations are solved numerically. The numerical simulation results show that the proposed method has good convergence in the condition of increasing numbers and power of input pump sources.  相似文献   
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