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991.
Yasemin Budama-Kilinc Rabia Cakir-Koc Serda Kecel-Gunduz Tolga Zorlu Yagmur Kokcu Bilge Bicak Zeynep Karavelioglu Aysen E. Ozel 《Journal of fluorescence》2018,28(5):1127-1142
Papain is a protease enzyme with therapeutic properties that are very valuable for medical applications. Poly(ε-caprolactone) (PCL) is an ideal polymeric carrier for controlled drug delivery systems due to its low biodegradability and its high biocompatibility. In this study, the three-dimensional structure and action mechanism of papain were investigated by in vitro and in silico experiments using molecular dynamics (MD) and molecular docking methods to elucidate biological functions. The results showed that the size of papain-loaded PCL nanoparticles (NPs) and the polydispersity index (PDI) of the NPs were 242.9 nm and 0.074, respectively. The encapsulation efficiency and loading efficiency were 80.4 and 27.2%, respectively. Human embryonic kidney cells (HEK-293) were used for determining the cytotoxicity of papain-loaded PCL and PCL nanoparticles. The in vitro cell culture showed that nanoparticles are not toxic at low concentrations, while toxicity slightly increases at high concentrations. In silico studies, which were carried out with MD simulations and ADME analysis showed that the strong hydrogen bonds between the ligand and the papain provide stability and indicate the regions in which the interactions occur. 相似文献
992.
Here we report the monitoring the instant creation of a new fluorescent signal (FS) aroused from a positively charged water-soluble fluorogenic probe, ethidium bromide (EtBr) in the presence of a radical initiator, ammonium persulfate (APS) and an accelerator, tetraethylmetilendiamine (TEMED) for evaluation of deoxyribonucleic acid (DNA) conformation. The results revealed that the occurred FS (λex?=?430 nm; λmax?=?525 nm) is a reduced form of EtBr (λex?=?480 nm; λmax?=?617 nm) and it is completely distinct from hydroethidine (λex?=?350 nm; λmax?=?430 nm), which is two-electron reduced form of EtBr. It was noticed that EtBr was reduced to a new FS during the polymerization of N, N dimethyacrylamide (DMAA) too, at 25 °C in the presence of APS and TEMED or at 55 °C with only APS, and the rate of formation of FS was increased upon treatment time. The effect of nanoclays such as Laponite XLG® and Laponite XLS®, which provide a protective environment for DNA in nature, were also investigated through the reduction process of EtBr in the absence and presence of a water soluble monomer DMAA. We demonstrated that DNA conformation might be evaluated by monitoring FS effectuated during the reduction of EtBr in the presence of nanoclays having positively and negatively charged surfaces. Protective property of DNA against the formation of reduced product was elucidated by carrying out the polymerization at 55 °C. The results revealed that the monitoring of formation of FS in the presence of radical initiator could lead to elucidate the conformation of DNA upon formation of intercalator complex. 相似文献
993.
The structural properties of Al isotopes are analysed using the relativistic mean field formalism with NL3 parameter set. The Glauber model technique is implemented to study the reaction dynamics for 23?28Al taking 12C as the target. The enhanced reaction cross section, high value of radius, narrow longitudinal momentum distribution and small proton separation energy of 23Al favours a proton halo structure for this nucleus. 相似文献
994.
State-of-the-art compact recirculating electron accelerators operating at intermediate energies (tens of MeV) are reviewed. The acceleration schemes implemented in the rhodotron, ridgetron, fantron, and cylindertron machines are discussed. Major accelerator components such as the electron guns, accelerating cavities, and bending magnets are described. The parameters of currently operating recirculating accelerators are tabulated, and applications of these accelerators in different processes of irradiation are exemplified. 相似文献
995.
The present study used differential scanning calorimetry, thermogravimetric analysis, and UV spectrometry to examine: i) the encapsulation of an organic UV filter 1-(4-methoxyphenyl)-3-(4- tert-butylphenyl)propane-1,3-dione (avobenzone) within modified dextrin and ii) the characteristics of these inclusion complexes (MDA). The properties of avobenzone emulsions with and without encapsulation in modified dextrin, the in vitro UV protection factor, dissolution and release, and the skin penetrability of avobenzone were also examined. The presence of inclusion complexes significantly decreased the tendency of the UV filter to penetrate the skin. In addition, such inclusion complexes should effectively prevent skin damage from radiation extending from the UVA to the UVC. 相似文献
996.
997.
Ching-Yang Cheng 《Transport in Porous Media》2012,91(3):877-888
This work studies the Soret and Dufour effects on the double-diffusive free convection over a downward-pointing vertical truncated
cone with variable wall heat and mass fluxes in fluid-saturated porous media. A coordinate transformation is used to derive
the nondimensional boundary-layer governing equations, and the obtained nonsimilar equations are then solved by the cubic
spline collocation method. Results for local surface temperature and the local surface concentration are presented as functions
of Soret parameters, Dufour parameters, power-law exponents, buoyancy ratios, and Lewis numbers. Results show that increasing
the Dufour parameter tends to increase the local surface temperature, while it tends to decrease the local surface concentration.
An increase in the Soret number leads to a decrease in the local surface temperature for buoyancy assisting flows, while it
leads to an increase in the local surface temperature for buoyancy opposing flows. Increasing the Soret number tends to increase
the local surface concentration. Moreover, the local surface temperature and the local surface concentration of the truncated
cones with higher power-law exponents are lower than those with lower exponents. 相似文献
998.
The paper presents a short review on the synthesis, characterisation and selected medical applications of poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) (P(S/PGL)) microspheres. The soap-free emulsion-polymerisation of styrene and α-tert-butoxy-ω-vinylbenzyl-polyglycidol macromonomer (PGL) in water yielded core-shell microspheres with a low particle-diameter dispersity
(ratio of the weight average particle diameter and the number average particle diameter). The interfacial fraction of PGL
units, estimated by XPS, was in the range of 0–42 mole % depending on the concentration of the macromonomer in the polymerisation
feed. The studies of adsorption of model proteins showed that the surface fraction of adsorbed protein was significantly reduced
when the PGL interfacial fraction was higher than 40 mole %. The P(S/PGL) particles with covalently immobilised proteins were
used for the preparation of photonic crystal assemblies suitable for applications in optical biosensors and the medical diagnostic
test for the detection of Helicobacter pylori antibodies in the blood serum. 相似文献
999.
This paper reports the fabrication and nanofiltration properties of a sol–gel derived microporous zirconia membrane. Effects
of synthesis parameters, including hydrolysis time, hydrolysis temperature, hydrolysis ratio and chelating agent dopant, on
the state and size of polymeric zirconia sol, were investigated. Highly reproducible and stable zirconia sol after refluxing
at 40 °C for 180 min, with an average particle size of approximately 8.6 nm, was synthesized with a recipe of [Zirconium n-propoxide]:
[Diethanolamine]: [1-propanol]: [H2O] being 1: 2.2: 28.7: 9.4 (in molar ratio). The sol was subsequently used for the fabrication of microporous ZrO2 membranes onto alumina supported mesoporous γ-Al2O3 layers. ZrO2 membranes with molecular weight cut-off (MWCO) of 354, 1,195, corresponding to the pore size of 0.94 and 1.75 nm, were successfully
fabricated. Ionic retention properties of such ZrO2 membranes with respect to electrolyte solutions, like MgCl2, CaCl2, NaCl and Na2SO4, were also determined. Effects of parameters such as concentration of salt solutions and trans-membrane pressure on retention
rates of microporous ZrO2 membranes were studied in detail. Results showed that zirconium n-propoxide derived microporous ZrO2 membranes exhibited comparatively high retention rates towards divalent ions like Mg2+ and Ca2+, while much lower retention rates were observed for mono-valent ion (Na+) in the present study, which are the characteristics of nanofiltration membranes. 相似文献
1000.