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The cellulose‐based hydrogel has occupied a pivotal position in almost all walks of life. However, the native cellulose can not be directly used for preparing hydrogel due to the complex non‐covalent interactions. Some literature has discussed the dissolution and modification of cellulose but has yet to address the influence of the pretreatment on the as‐prepared hydrogels. Firstly, the "touching" of cellulose by derived and non‐derived solvents was introduced, namely, the dissolution of cellulose. Secondly, the "conversion" of functional groups on the cellulose surface by special routes, which is the modification of cellulose. The above‐mentioned two parts were intended to explain the changes in physicochemical properties of cellulose by these routes and their influences on the subsequent hydrogel preparation. Finally, the "reinforcement" of cellulose‐based hydrogels by physical and chemical techniques was summarized, viz., improving the mechanical properties of cellulose‐based hydrogels and the changes in the multi‐level structure of the interior of cellulose‐based hydrogels. [ABSTRACT FROM AUTHOR]

Efficient utilization of pesticides has presented various advantages in the ecological environment, food safety, and agricultural sustainability. Pesticide microcapsule could significantly improve the pesticide utilization ratio, and thus, we prepared a sustained‐release microcapsule from cellulose nanocrystal (CNCs) stabilized Pickering emulsion template. The NaCl was added to overcome the strong electrostatic repulsion among CNCs for forming a stable oil‐in‐water (O/W) CNCs‐based Pickering emulsion template, followed by crosslinking with hexamethylene diisocyanate on the interface. UV–vis and zeta‐potential were used to characterize the as‐prepared Pickering emulsion, and the stability and emulsion fraction were calculated. Results indicated that NaCl contributed to the stability of Pickering emulsion, even at a low concentration. The obtained CNCs‐based microcapsule was characterized by FT‐IR, XRD, SEM, TG‐DTG, and three‐phase contact angles. The microcapsule presented an encapsulation efficiency of 96.76% and sustained release of the imidacloprid for more than 82 h. Results indicated the potential for loading and sustained release of imidacloprid, which is beneficial to the environment, food, and agriculture. [ABSTRACT FROM AUTHOR]

Abstract: The large amount of dye wastewater requires efficient techniques, e.g., adsorption by activated carbon (AC), for removal of dyes to decrease water pollution. AC was modified by the basic ionic liquid 1‐butyl‐3‐methylimidazolium hydroxide. The surface functional groups of AC changed evidently as detected by Fourier transform infrared spectroscopy and Boehm titration. To evaluate the influence of functional group change on adsorption performance, AC and modified activated carbon (MAC) were employed to remove methylene blue. The results indicated an increase of adsorbance with lapse of contact time. The adsorption capability of AC was distinctly higher than that of MAC. From kinetic studies it follows that the pseudo‐second‐order kinetic model can well describe the adsorption process. [ABSTRACT FROM AUTHOR]

Objective: To assess the benefits of use of a tourniquet in one limb in patients undergoing simultaneous bilateral total knee arthroplasty (TKA). Methods: A prospective randomized trial was designed to evaluate the outcomes of unilateral tourniquet use during simultaneous bilateral TKA. A total of 52 (36 women and 16 men) patients with osteoarthritis who underwent simultaneous bilateral primary TKA between January 2010 and January 2015 were assigned randomly to tourniquet (TG) or non-tourniquet (NG) groups prior to surgery. Operating time, pain score, range of motion, first active straight-leg raise time, swelling, wound healing, deep vein thrombosis, and Knee Society score were observed. Results: Mean operating time in the TG group was shorter than that in the NG group (P < 0.05). Postoperative pain was measured by a visual analog scale (VAS) and straight-leg raise time, which was lower and shorter in limbs operated without the use of a tourniquet (P < 0.05). In addition, this group had less postoperative swelling and lower incidence of wound complications in the early postoperative period (P < 0.05). There was no significant difference in the range of motion (ROM), deep venous thrombosis incidence, and Knee Society scores between the two groups. Conclusions: Tourniquet use in bilateral TKA can reduce intraoperative time but was associated with a higher incidence of wound complications and larger postoperative knee swelling. [ABSTRACT FROM AUTHOR]

An automated online solid-phase extraction with restricted-access material combined with high-performance liquid chromatography and tandem mass spectrometry was developed and validated for the simultaneous quantification of vanillin and its vanillic acid metabolite in human plasma. After protein precipitation by methanol, which contained the internal standards, the supernatant of plasma samples was injected to the system, the endogenous large molecules were flushed out, and target analytes were trapped and enriched on the adsorbent, resulting in a minimization of sample complexity and ion suppression effects. Calibration curves were linear over the concentrations of 5-1000 ng/mL for vanillin and 10-5000 ng/mL for vanillic acid with a coefficient of determination >0.999 for the determined compounds. The lower limits of quantification of vanillin and vanillic acid were 5.0 and 10.0 ng/mL, respectively. The intra- and inter-run precisions expressed as the relative standard deviation were 2.6-8.6 and 3.2-10.2%, respectively, and the accuracies expressed as the relative error were in the range of -6.1 to 7.3%. Extraction recoveries of analytes were between 89.5 and 97.4%. There was no notable matrix effect for any analyte concentration. The developed method was proved to be sensitive, repeatable, and accurate for the quantification of vanillin and its vanillic acid metabolite in human plasma. [ABSTRACT FROM AUTHOR]

A high-performance liquid chromatography method with on-line precolumn enzymatic reaction for the screening of xanthine oxidase inhibitors in natural extracts was developed. In this method, the enzymatic reaction occurred at the capillary inlet during a predetermined waiting period, after which the reaction product, uric acid, was separated and detected by liquid chromatography using ultraviolet absorption at 295 nm. Enzyme inhibition can be read out directly from the reduced peak area of uric acid in comparison to a reference chromatogram obtained in the absence of any inhibitor. In the present study, the availability of on-line precolumn enzymatic reaction with ultraviolet detection was firstly evaluated by determining the inhibitory mechanism and IC50 values of allopurinol, a commercially available positive drug. Then, the newly developed method was applied to screening of ten natural extracts from traditional Chinese medicine and as a result, the extract of Epimedium sagittatum (Sieb. et Zucc.) Maxim was found to be most positive for xanthine oxidase inhibition. The results obtained were compared with those obtained by offline enzyme assay and the effectiveness of the present method was confirmed. A rapid, low-cost, and fully automated method for xanthine oxidase inhibitor screening was proposed. [ABSTRACT FROM AUTHOR]