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Objective： This study aims to optimize the adsorption of enzymatic hydrolysis of Pueraria protein by macroporous resin and maximize the antioxidant properties in vitro. Methods: The Box-Behnken response surface method was used to determine the optimization of adsorption of enzymatic hydrolysis of Pueraria protein. Using VC as a control, the antioxidant activity of Kase was determined before and after purification under the optimal purification process. Results： The optimal adsorption-desorption process of macroporous resin is: the mass concentration of the sample solution was 10.0 mg/mL, the flow rate of the eluent was 2.6 mL/min, and the volume fraction of ethanol in the eluent was 74%. After adsorption, the content of enzymatic hydrolysis of Pueraria protein increased to 37.19%. The scavenging rate of DPPH, ABTS+, and hydroxyl radicals of Pueraria Mirifica protease after adsorption was stronger than before adsorption. Conclusion： This study shows that enzymatic hydrolysis of Pueraria protein after adsorption of macroporous resin has good antioxidant effect, which can be used as a potential protein polypeptide in food, providing data reference for further research of enzymatic hydrolysis of Pueraria protein.

Atomic layer deposition is a key technique for preparing large area uniformity, three-dimensional conformal, and ultrathin films due to its sequential self-limiting saturated chemisorption properties. Electric fields of varying magnitudes and directions were applied on Si, Al2O3, Au, and Ni substrates in Pt plasma enhanced atomic layer deposition processes. Studying the influences of electric fields on the initial nucleation and growth of Pt films on different substrates helps to understand the dynamic knowledge and underlying physical mechanisms so as to obtain ultrathin, continuous films and full control over the morphology and distribution of deposited materials. The XPS results reveal that the Pt coverage rate increases on all substrates with applied voltages. The induced dipole moment causes the (MeCp)PtMe3 molecule to rotate in a certain direction resulting in a more compact arrangement, and the energy generated by electric fields also helps the dissociation of methyl, ethyl, Cp, and MeCp ligands, which greatly mitigate the spatial site resistance effect, thus improving initial monolayer chemisorption efficiency and the Pt coverage. We also find that Pt prefers to grow in the (111) direction due to the increase in adsorption of (MeCp)PtMe3 molecules caused by the gradient forces under electric fields. However, applied electric fields can also influence the morphology by inducing surface diffusion and acting on plasma species. [ABSTRACT FROM AUTHOR]

Objective: To obtain the optimal enzyme and preparation process for Schisandra chinensis protein peptides and investigate its in vitro antioxidant activity. Methods: Seven proteases were used to hydrolyze Schisandra chinensis protein. Based on the degree of hydrolysis, free radical scavenging activity, polypeptide yield and content of different hydrolysates of Schisandra chinensis protein and the comprehensive evaluation of molecular weight in SDS-PAGE, the optimal protease was screened. The DPPH free radical scavenging rate was used as the index, and the optimal enzymatic hydrolysis process was determined by single factor test combined with response surface analysis. The scavenging ability of O2-*, *OH, DPPH*, ABTS+*, Fe2+ chelating ability and Fe3+ reducing ability of Schisandrae chinensis protein peptides were analyzed and compared with Schisandra chinensis protein. Results: The optimum enzyme for the preparation of Schisandra chinensis protein peptides was alkaline protease. The optimum enzymatic hydrolysis parameters were as follows: substrate concentration 5%, enzyme-to-substrate ratio 1%, enzymatic hydrolysis time 3 h, enzymatic hydrolysis temperature 55 °C, pH9.0. Under these conditions, the polypeptide content was 88.61%, the degree of hydrolysis was 24.21%, and the DPPH* scavenging rate was 86.96%. The free radical scavenging ability and reducing ability of Schisandrae chinensis protein peptides were better than those of Schisandrae chinensis protein. Conclusion: This study determined the optimum enzyme and hydrolysis process of Schisandrae chinensis protein peptides, and pointed out that Schisandrae chinensis protein peptides had better antioxidant activity in vitro and could be used as a natural antioxidant. [ABSTRACT FROM AUTHOR]

A long-wavelength triggered cationic iridium(III) complex, Ir5, and its corresponding nanoparticles with the ability to generate type I and type II reactive oxygen species have been synthesised. The complex targets mitochondria and achieves an excellent photodynamic therapy effect in hypoxic cancer cells. [ABSTRACT FROM AUTHOR]

Background: Among hemodialysis patients, acute superior mesenteric artery (SMA) thrombosis a condition with a high mortality rate. Very few larger case series have been reported. Method: We reviewed eight hemodialysis patients with diabetes mellitus and SMA thrombosis managed with endovascular therapy in our institution. Demographic, clinical, and radiological data were described. The patency of the SMA was assessed by computed tomography angiography (CTA) at one month after the endovascular procedure. At the last visit, clinical symptoms and check of mortality were recorded. Results: Multidetector CTA scan revealed severe stenosis of SMA in 6 patients and SMA occlusion in the other two patients. The severe stenosis of SMA were verified by angiography. Balloon angioplasty without stenting was performed to obtain satisfactory patency of SMA. Seven of eight patients achieved resolution of abdominal pain after the endovascular procedure. One patient died of suspected intestinal necrosis after 6 days of balloon angioplasty. All seven surviving patients did not experience a recurrence of symptoms with a median follow‐up of 2 years. No significant residual stenotic or occlusive lesions were noted in follow‐up CTA at one month after the endovascular procedure. Conclusion: SMA thrombosis should be systematically suspected in hemodialysis patients experiencing abdominal pain. Prompt diagnosis of SMA thrombosis as soon as possible and early endovascular therapy are required to obtain a favorable prognosis in the hemodialysis patient with SMA thrombosis. [ABSTRACT FROM AUTHOR]