Diabetic foot ulcer (DFU) is a common complication in patients with diabetic hyperglycemia, which leaves patients at increased high risk of morbidity, infection, nontraumatic limb amputations, and even early death. [1-5] Among various efforts to address this urgent issue, wound dressings are effective strategies to provide an optimal environment for wound repair. [6,7] Traditional wound dressings for DFU treatment typically cover rubber, electrospun nanofiber, cotton wool, natural or synthetic bandages, and gauzes. [8,9] Although these dry dressings are convenient to control the initial state of wound healing, they tend to adhere to the wound area once the absorbed blood and exudate dry out. [7] Besides, the dry dressings still suffer from limitations of maintaining a moisture environment, allowing gaseous exchange, and preventing infection. [6,7] In this context, a wound dressing that can deal with the above shortcomings would be ideal to speed up diabetic foot wounds healing and improve treatment outcomes. In recent years, hydrogels have generated tremendous interest in wound healing applications. [10-16] As water-based soft materials, hydrogels can facilitate wound healing by absorbing wound exudate, preventing wound desiccation, and isolating the wound from the environment, which makes them the best choice for wound healing. [17,18] However, the currently available hydrogel dressings still require to be changed frequently, which is a laborious process and inevitably cause reinjury of the wounds, wound infection, delayed healing time, and personal suffering. [19] To this end, on-demand dissolvable hydrogels represent a new class of emerging "smart" wound dressings that can be readily operated and painlessly removed. [19-24] Generally, this type of hydrogels can form in situ and dissolve on-demand via physical crosslinking cases and chemical crosslinking cases. The dissolution of physically crosslinked hydrogels is based on physical interactions, such as molecular entanglements and/or secondary forces (e.g., ionic, H-bonding, and hydrophobic associations). [19,20,22,23] Diabetic foot ulcers (DFU) remain a very considerable health care burden, and their treatment is difficult. Hydrogel-based wound dressings are appealing to provide an optimal environment for wound repair. However, the currently available hydrogel dressings still need surgical or mechanical debridement from the wound, causing reinjury of the newly formed tissues, wound infection, delayed healing time, and personal suffering. Additionally, to meet people's increasing demand, hydrogel wound dressings with improved performance and multifunctionality are urgently required. Here, a new multifunctional supramolecular hydrogel for on-demand dissolvable diabetic foot wound dressings is designed and constructed. Based on multihydrogen bonds between hydrophilic polymers, the resultant supramolecular hydrogels present controlled and excellent properties, such as good transparency, antibacterial ability, conductive, and self-healing properties. Thus, the sup...

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Wound infections are serious medical complications that can endanger human health. Latest researches show that conductive composite materials may make endogenous/exogenous electrical stimulation more effective, guide/comb cell migration to the wound, and subsequently promote wound healing. To accelerate infected wound healing, a novel medical silver nanoparticle-doped conductive polymer-based hydrogel system (Ag NPs/CPH) dressing with good conductivity, biocompatibility, and mechanical and antibacterial properties was fabricated. For the hydrogel dressing, Ag NPs/CPH, polyvinyl alcohol (PVA), and gelatin were used as the host matrix materials, and phytic acid (PA) was used as the cross-linking agent to introduce conductive polyaniline into the matrix, with antibacterial Ag NPs loaded via impregnation. After a series of analyses, the material containing 5 wt% of PVA by concentration, 1.5 wt% gelatin, 600 μL of AN reactive volume, and 600 μL of PA reactive volume was chosen for Ag NPs/CPH preparation. XPS and FTIR analysis had been further used to characterize the composition of the prepared Ag NPs/CPH. The test on the swelling property showed that the hydrogels had abundant pores with good water absorption (≈140% within 12 h). They can be loaded and continuously release Ag NPs. Thus, the prepared Ag NPs/CPH showed excellent antibacterial property with increasing duration of immersion of Ag NPs. Additionally, to evaluate in vivo safety, CCK-8 experiments of HaCat, LO2 and 293T cells were treated with different concentrations of the Ag NPs/CPH hydrogel soaking solution. The experimental results showed the Ag NPs/CPH had no significant inhibitory effect on any of the cells. Finally, an innovative infection and inflammation model was designed to evaluate the prepared Ag NPs/CPH hydrogel dressing for the treatment of severely infected wounds. The results showed that even when infected with bacteria for long periods of time (more than 20 h), the proposed conductive antibacterial hydrogel could treat severely infected wounds.

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Long-term polluted rivers often lead to the accumulation of heavy metals in sediments. Anthropogenic activities or biological disturbances break the adsorption balance, causing them to return from the bottom mud to the overlying water and change the aquatic environment. In order to understand the variation of heavy metals between sediments and river water, we collected the riverbed sediments in the polluted Xinhe River and carried out static continuous infiltration and dynamic uninterrupted disturbance experiments. The leaching experiment shows that the absorbability of Cd and Pb is stronger than Cr in the sediment; at the same time, the properties of the medium have a great influence on the adsorption of heavy metals. The disturbance can prompt heavy metals in the sediment to resuspend into the overlying water. The impact is the greatest during the first 12 h, and the influence degree is stronger in the relatively static water than in the moving river. In addition, pH and other factors have different degrees of influence on the desorption of heavy metals.

Background Neuroblastoma is one of the common extracranial tumors in children (infants to 2 years), accounting for 8 ~ 10% of all malignant tumors. Few special drugs have been used for clinical treatment currently. Results In this work, herbal extract ginsenosides were used to synthesize fluorescent ginsenosides carbon nanodots via a one-step hydrothermal method. At a low cocultured concentration (50 µg·mL− 1) of ginsenosides carbon nanodots, the inhibition rate and apoptosis rate of SH-SY5Y cells reached ~ 45.00% and ~ 59.66%. The in vivo experiments showed tumor volume and weight of mice in ginsenosides carbon nanodots group were ~ 49.81% and ~ 34.14% to mice in model group. Since ginsenosides were used as sole reactant, ginsenosides carbon nanodots showed low toxicity and good animal response. Conclusion Low-cost ginsenosides carbon nanodots as a new type of nanomedicine with good curative effect and little toxicity show application prospects for clinical treatment of neuroblastoma. It is proposed a new design for nanomedicine based on bioactive carbon nanodots, which used natural bioactive molecules as sole source.

As a major agricultural province in China, Northeast China produces a lot of biomass while its grain yield is high. Open burning is an efficient and convenient way to remove biomass. However, air pollutants (PM2.5, CO, VOCs) will be released in the process of biomass combustion, which will have a certain impact on Regional Environmental quality, atmospheric visibility and human health. Because of the various type of biomass, their combustion products and effects are different. In this study, there collected peanut hull, rice husk, straw and wood particles, and carried out the simulated combustion experiment in the laboratory environment simulation chamber. The inorganic elements, water-soluble ions and speciation analysis of combustion products were determined. The results showed that the content of Zn was higher than that of carcinogenic element in the eight inorganic elements after combustion. The water-soluble ion emission factors of wheat straw and wood particles are larger than those of peanut hull and rice husk, and the water-soluble ions are mainly K+ and CL. Through the morphology analysis of combustion products, it can be seen that different types of biomass have different morphology after combustion, which are mainly strip, column and particle. Combined with energy spectrum analysis, it is found that the content of K and CL is high. The results lay a theoretical foundation for the study of local biomass combustion and provide data for the determination of local biomass combustion emission characteristics.

In this paper, Panax ginseng cyclophilin (PgCyP) was successfully obtained through a genetic engineering technique. A bioinformatics method was used to analyze the physicochemical properties and structure of PgCyP. The results showed that PgCyP belongs to the cyclophilin gene family. The protein encoded by the PgCyP gene contains the active site of PPIase (R62, F67, H133) and a binding site for cyclosporine A (W128). The relative molecular weight of PgCyP is 187.11 kDa, the theoretical isoelectric point is 7.67, and it encodes 174 amino acids. The promoter region of PgCyP mainly contains the low-temperature environmental stress response element (LTR), abscisic acid-responsive cis-acting element (ABRE), and light-responsive cis-acting element (G-Box). PgCyP includes a total of nine phosphorylation sites, comprising 4 serine phosphorylation sites, 3 threonine phosphorylation sites, and 2 tyrosine phosphorylation sites. PgCyP was recombined and expressed in vitro, and its recombinant expression was investigated. Furthermore, it was found that the recombinant PgCyP protein could effectively inhibit the germination of spores and the normal growth of mycelium in vitro. Further experiments on the roots of susceptible Arabidopsis thaliana showed that the PgCyP protein could improve the resistance of Arabidopsis to Phytophthora cactorum. The findings of this study provide a basis for the use of the PgCyP protein as a new type of green biopesticide.