Thiolation-Based Protein-Protein Hydrogels for Improved Wound Healing.

The limitations of protein-based hydrogels, including their insufficient mechanical properties and restricted biological functions, arise from the highly specific functions of proteins as natural building blocks. A potential solution to overcome these shortcomings is the development of protein-protein hydrogels, which integrate structural and functional proteins. In this study, a protein-protein hydrogel formed by crosslinking bovine serum albumin (BSA) and a genetically engineered intrinsically disordered collagen-like protein (CLP) through Ag─S bonding is introduced. The approach involves thiolating lysine residues of BSA and crosslinking CLP with Ag+ ions, utilizing thiolation of BSA and the free-cysteines of CLP. The resulting protein-protein hydrogels exhibit exceptional properties, including notable plasticity, inherent self-healing capabilities, and gel-sol transition in response to redox conditions. In comparison to standalone BSA hydrogels, these protein-protein hydrogels demonstrate enhanced cellular viability, and improved cellular migration. In vivo experiments provide conclusive evidence of accelerated wound healing, observed not only in murine models with streptozotocin (Step)-induced diabetes but also in zebrafish models subjected to UV-burn injuries. Detailed mechanistic insights, combined with assessments of proinflammatory cytokines and the expression of epidermal differentiation-related proteins, robustly validate the protein-protein hydrogel's effectiveness in promoting wound repair.

Joint Optimization of Energy Consumption and Data Transmission in Smart Body Area Networks.

In Wireless Body Area Networks (BAN), energy consumption, energy harvesting, and data communication are the three most important issues. In this paper, we develop an optimal allocation algorithm (OAA) for sensor devices, which are carried by or implanted in human body, harvest energy from their surroundings, and are powered by batteries. Based on the optimal allocation algorithm that uses a two-timescale Lyapunov optimization approach, we design a framework for joint optimization of network service cost and network utility to study energy, communication, and allocation management at the network edge. Then, we formulate the utility maximization problem of network service cost management based on the framework. Specifically, we use OAA, which does not require prior knowledge of energy harvesting to decompose the problem into three subproblems: battery management, data collection amount control and transmission energy consumption control. We solve these through OAA to achieve three main goals: (1) balancing the cost of energy consumption and the cost of data transmission on the premise of minimizing the service cost of the devices; (2) keeping the balance of energy consumption and energy collection under the condition of stable queue; and (3) maximizing network utility of the device. The simulation results show that the proposed algorithm can actually optimize the network performance.

Experimental Investigations on Bond Behavior between FRP Bars and Advanced Sustainable Concrete.

In response to resource shortage and carbon dioxide emissions, an innovative type of sustainable concrete containing LC3, seawater, sea sand, and surface-treated recycled aggregates is proposed in this study to replace traditional concrete. To understand the bond properties between the sustainable concrete and CFRP bars, an investigation was conducted on the bond behavior between sand-coated CFRP bars and advanced sustainable concrete. Pull-out tests were carried out to reveal the failure mechanisms and performance of this bond behavior. The results showed that the slip increased monotonically along with the increase in confinement. The bond strength increased up to approximately 15 MPa, and the critical ratio of C/D was reached. The critical ratio approached 3.5 for the Portland cement groups, while the ratio was determined as approximately 4.5 when LC3 was introduced. When the proportion of LC3 reached 50%, there was a reduction in bond strength. A multisegmented modified bond-slip model was developed to describe the four-stage bond behavior. In terms of bond strength and slip, the proposed advanced concrete exhibited almost identical bond behavior to other types of concrete.

Recycled GFRP Aggregate Concrete Considering Aggregate Grading: Compressive Behavior and Stress-Strain Modeling.

Fiber-reinforced polymer (FRP) composites have been used in various industries, thus a large amount of FRP wastes have been generated due to the out-of-service of FRP products. Recycling FRP wastes into coarse aggregates to replace natural coarse aggregates (NCA) to form the recycled FRP aggregate concrete (RFAC) is a potential approach to dispose of huge quantities of FRP wastes with low environmental impact. In this paper, waste glass FRP (GFRP) bars were cut into particles of 12 sizes to enable the grading of recycled FRP aggregate (RFA) as similar as possible to that of NAC. The influence of different RFA volume replacement ratios (0%, 30%, 50%, 70%, 100%) on the compressive performance of RFAC was investigated based on uniaxial compression tests of 15 standard cylinders. The results showed that the failure mode of RFAC was different from that of NAC. As the RFA replacement ratio increased, the compressive strength and elastic modulus of the RFAC gradually decreased, but its post-peak brittleness was significantly mitigated compared to NAC. The Poisson's ratio of RFAC increased with the increase in the RGFA replacement ratio at the elastic stage and was smaller than that of NCA concrete. Both the existing stress-strain models developed for NAC and recycled aggregate concrete (RAC) were found not fit for the RFAC. Thus, a new stress-strain model that was applicable to RFAC was developed by modifying the classical existing model, and a good agreement between the model predictions and test data was reached.

Does electroacupuncture benefit mixed urinary incontinence? A systematic review and meta-analysis with trial sequential analysis.

INTRODUCTIN AND HYPOTHESIS: Mixed urinary incontinence (MUI) comprises a combination of urgency and stress. The efficacy and safety of electroacupuncture (EA) for the treatment of MUI remain unclear. OBJECTIVE: To assess the efficacy and safety of EA in treating MUI. METHODS: We searched PubMed, CENTRAL, Embase, Web of Science, four Chinese databases, clinical research registration platforms, grey literature, and the reference lists of the selected studies. Risk of bias and quality were evaluated using the Revman 5.4 and Jadad scores. Meta-analysis was performed using Stata 15.1 software. Trial sequential analysis (TSA) was used to assess the stability of the results. RESULTS: Eight randomized controlled trials comprising 847 patients were included. The meta-analysis results showed that compared with antimuscarinic drugs plus pelvic floor muscle training, EA resulted in significantly less pad weight on the 1-h pad test and statistically significantly lower severity scores on the International Consultation on Incontinence Questionnaire Short Form. The change in the 72-h incontinence episode frequency difference was not statistically significant, and there was no outcome of overall response rate and quality of life in this meta-analysis. Few adverse events occurred in the EA group. The TSA results suggested that the result of change from baseline in the 1-h pad test was stable and the evidence was conclusive. CONCLUSIONS: EA could be a potential treatment option for MUI and is relatively safe. Nevertheless, because of the limitations of this study, our conclusions should be interpreted with caution, and further studies are needed to confirm the comprehensive clinical efficacy and placebo effect of EA.

A novel nonenzymatic hydrogen peroxide sensor based on MnO2/graphene oxide nanocomposite.

A new electrocatalyst, MnO(2)/graphene oxide hybrid nanostructure was successfully synthesized for the nonenzymatic detection of H(2)O(2). The morphological characterization was examined by scanning electron microscopy and transmission electron microscopy. The MnO(2)/graphene oxide based electrodes showed high electrochemical activity for the detection of H(2)O(2) in alkaline medium. The nonenzymatic biosensors displayed good performance along with low working potential, high sensitivity, low detection limit, and long-term stability, which could be attributed to the high surface area of graphene oxide providing for the deposition of MnO(2) nanoparticles. These results demonstrate that this new nanocomposite with the high surface area and electrocatalytic activity offers great promise for new class of nanostructured electrode for nonenzymatic biosensor and energy conversion applications.

An excellent enzyme biosensor based on Sb-doped SnO2 nanowires.

Sb-doped SnO(2) nanowires were synthesized via thermal evaporation. Scanning electron microscopic, transmission electron microscopic, X-ray diffraction, current-voltage, and electrochemical impedance spectroscopy experiments have been used to characterize the structural and electrical behaviors of the nanowires. A mediator-free horseradish peroxidase-based H(2)O(2) biosensor was constructed through the Sb-doped SnO(2) nanowires used as the immobilization matrix for the enzymes. In comparison with the undoped SnO(2) nanowires, Sb-doped SnO(2) nanowires exhibited excellent electron transfer properties for the enzymes and higher electroactivity toward H(2)O(2). The biosensors displayed good performance along with high sensitivity, wide linear range, and long-term stability. Those can be attributed to the enhanced carrier density arising from Sb doping and biocompatible microenvironment provided by the Sb-doped SnO(2) nanowires. This study demonstrated that Sb-doped SnO(2) nanowires were promising platform for the construction of mediator-free biosensors and provided new further fundamental insights into the study of nanoscience and nanodevices.

A novel non-enzymatic hydrogen peroxide sensor based on Mn-nitrilotriacetate acid (Mn-NTA) nanowires.

A novel non-enzymatic hydrogen peroxide sensor was realized from Mn-nitrilotriacetate acid (Mn-NTA) nanowires, which were successfully fabricated via a facile hydrothermal route. Cyclic voltammetry (CV) revealed that the Mn-NTA nanowires exhibited direct electrocatalytic activity for the oxidation of H(2)O(2) in phosphate buffer solution. The sensor showed linear response to H(2)O(2) at the concentrations range from 5 x 10(-6)M to 2.5 x 10(-3)M with a detection limit of 2 x 10(-7)M. The sensitivity was up to 78.9 microA mM(-1)cm(-2). These results indicated that the Mn-NTA nanowires were promising in realizing non-enzymatic H(2)O(2) detection.

Electrografted poly(N-mercaptoethyl acrylamide) and Au nanoparticles-based organic/inorganic film: a platform for the high-performance electrochemical biosensors.

In this study, we describe the use of the combination of eletrografting poly(N-mercaptoethyl acrylamide) and Au nanoparticles in the construction of high-performance biosensors. The poly(N-mercaptoethyl acrylamide) was electrografted onto the glassy carbon electrode surface, which provided a strongly adhering primer film for the stable attachment of Au nanoparticles and horseradish peroxidase (HRP) enzymes. The performances of the biosensors based on the HRP immobilized in the Au/poly(N-mercaptoethyl acrylamide) composite film were investigated. A couple of redox peaks were obtained, indicating that the Au nanoparticles could facilitate the direct-electron transfer between HRP and the underlying electrode. The biosensor showed an excellent electrocatalytic activity toward the reduction of hydrogen oxide and long-term stability, owing to the stable electrografted film and biocompatible Au nanoparticles. Our results demonstrate that the combination of electrografting and Au nanoparticles provides a promising platform for the immobilization of biomolecules and analysis of redox enzymes for their sensing applications.

Electrocatalytic activity of horseradish peroxidase/chitosan/carbon microsphere microbiocomposites to hydrogen peroxide.

Colloidal carbon microspheres (CMS) are dispersed in chitosan (CHIT) solution to form an organic-inorganic hybrid with excellent micro-environment for the immobilization of biomolecules. A novel amperometric biosensor for the determination of hydrogen peroxide (H(2)O(2)) has been constructed by entrapping horseradish peroxidase (HRP) in as-synthesized CMS/CHIT hybrid. The modification of glassy carbon electrode is made by a simple solution-evaporation method. The electrochemical properties of the biosensor are characterized in electrochemical methods. The proposed biosensor shows high sensitive determination and fast response to H(2)O(2) at -0.15 V. The constructed HRP/CHIT/CMS/GC electrode also exhibits a fine linear correlation with H(2)O(2) concentration. The calculated value of the apparent Michaelis-Menten constant, 2.33 mM, suggests that the HRP in CMS/CHIT hybrid keeps its native bioactivity and has high affinity for H(2)O(2).

A novel amperometric biosensor based on NiO hollow nanospheres for biosensing glucose.

NiO hollow nanospheres were synthesized by controlled precipitation of metal ions with urea using carbon microspheres as templates, which were for the first time adopted to construct a novel amperometric glucose biosensor. Glucose oxidase was immobilized on the surface of hollow nanospheres through chitosan-assisted cross-linking technique. Due to the high specific active sites and high electrocatalytic activity of NiO hollow nanospheres, the constructed glucose biosensors exhibited a high sensitivity of 3.43 microA/mM. The low detection limit was estimated to be 47 microM (S/N=3), and the Michaelis-Menten constant was found to be 7.76 mM, indicating the high affinity of enzyme on NiO hollow nanospheres to glucose. These results show that the NiO hollow nanospheres are a promising material to construct enzyme biosensors.

Rapid and ultrahigh ethanol sensing based on Au-coated ZnO nanorods.

Rapid and ultrahigh sensing is realized from Au-coated ZnO rods with diameters down to 15 nm. Both the small diameters and the Au coating make the surface-depletion effect more pronounced for gas sensing. Such enhanced surface depletion increases the sensitivity, lowers the operation temperature and decreases the response time. A sensitivity of 89.5-100 ppm ethanol is obtained with response time shorter than 2 s at 300 °C, and the operation temperature can be as low as 150 °C. It is found that the Au coating improves the sensitivity by three times; this is much higher than that of noble metal-doped metal oxide sensors controlled by a grain-boundary barrier. Our results imply that the surface-depletion model is very helpful in fabricating high performance gas sensors.