Mild hyperthermia-assisted chitosan hydrogel with photothermal antibacterial property and CAT-like activity for infected wound healing.

Infected wounds pose a serious threat to public health and pose a significant challenge and financial burden worldwide. The treatment of infected wounds is now an urgent problem to be solved. Herein, mild hyperthermia-assisted hydrogels composed of carboxymethyl chitosan (CMCs), oxidized dextran (Odex), epigallocatechin gallate (EGCG) and PtNPs@PVP (CAT-like nanoenzymes) were proposed for the repair of infected wounds. The incorporation of PtNPs@PVP nanoenzymes give the hydrogels excellent photothermal property and CAT-like activity. When the temperature is maintained at 42-45 °C under 808 nm near infrared (NIR) exposure, the CMCs/Odex/EGCG/Nanoenzymes (COEN2) hydrogel demonstrated highly enhanced antibacterial ability (95.9 % in vivo), hydrogen peroxide (H2O2) scavenging ratio (85.1 % in vitro) and oxygen supply (20.7 mg/L in vitro). Furthermore, this mild-heat stimulation also promoted angiogenesis in the damaged skin area. Overall, this multifunctional hydrogel with antibacterial, antioxidant, oxygen supply, hemostasis, and angiogenesis capabilities has shown great promise in the repair of infected wounds. This study establishes the paradigm of enhanced infected wound healing by mild hyperthermia-assisted H2O2 scavenging, oxygen supplemental, and photothermal antibacterial hydrogels.

Improvement, Validation, and Analysis of Colles Fracture Treated with an Integrated Retainer Pad Splint.

Objective: To observe the effectiveness and safety of the Colles fracture treated with the integrated retainer pad splint and to compare the clinical and radiological outcomes of the integrated retainer pad splint and the traditional bamboo curtain splint in the treatment of the Colles fracture. Methods: A total of 100 patients with Colles fractures were randomly divided into two groups: the treatment group was fixed with the integrated retainer pad splint (IS), and the control group was fixed with the traditional bamboo curtain splint (TS).The range of wrist motion was measured at follow-up examinations, and volar inclination, ulnar deviation, and radial height were measured on radiographs. Regular follow-up wrist imaging examinations and functional examinations were performed before reduction, after reduction, and at the 1st, 3rd, 5th, and 8th weeks. The two groups were compared in terms of convenience, fracture healing time, X-ray data of volar inclination, ulnar deviation, radial height, and wrist joint function. The relevant data were analyzed with SPSS 25.0 statistical software. Results: There were no notable differences in gender, age, and injured side between IS and TS groups. In terms of operation time, IS was better than the TS group (P < 0.05), and the operation time in the IS group was shorter. On the basis of X-ray data of volar inclination, ulnar deviation, and radial height measured on radiographs, the difference between the IS and TS groups was statistically significant (P < 0.05), which showed that the IS group was more stable in fracture fixation and had less reduction loss during the treatment process. At the 8th week of treatment, the wrist Gartland-Werley score of the two groups showed that the two fixation methods are equivalent in restoring wrist joint function (P > 0.05); however, in terms of the excellent and good rate of wrist joint function, the IS group scored 96% was higher than the TS group (80%). Conclusion: Compared with the traditional bamboo curtain splint, the integrated retainer pad splint is more convenient and stable, and it has less reduction loss during the treatment. Repair of the Colles fracture using the integrated retainer pad splint with external fixation results in nearly normal return of function, which is significantly better than using the traditional bamboo curtain splint.

Hollow gold nanoshells-incorporated injectable genetically engineered hydrogel for sustained chemo-photothermal therapy of tumor.

BACKGROUND: Combined therapy has demonstrated to be an effective strategy for cancer therapy. Herein, an injectable hydrogel based on the genetically engineered polypeptide and hollow gold nanoshells (HAuNS) has been developed for chemo-photothermal therapy of HepG2 tumor. METHODS: PC10A/DOX/HAuNS nanogel was prepared with layer-by-layer through the adsorption of DOX and PC10A successively. DOX with positive charge and PC10A with negative charge were coated step by step onto the surface of negatively charged HAuNS. The multifunctional hydrogel PC10A/DOX/HAuNS were prepared via dissolving hybrid PC10A/DOX/HAuNS nanogel in polypeptide PC10A. Chemotherapy drug DOX in the PC10A/DOX/HAuNS hydrogel was absorbed on the HAuNS and directly embedded in the PC10A hydrogel, which contributes to sequentially release of the drug. Specifically, DOX adsorbed on the HAuNS could be released slowly for sustainable chemotherapy. RESULTS: The PC10A/DOX/HAuNS hydrogel could pass 26-gauge needle without clogging, indicating that it is injectable. In addition, the PC10A/DOX/HAuNS hydrogel possessed outstanding photothermal effect and photothermal stability. In both in vitro cell and in vivo tumor-bearing mice experiments, a remarkably enhance tumor inhibition was observed by the combined therapy of chemo-photothermal therapy compared with photothermal therapy or chemotherapy alone. CONCLUSIONS: The combined chemotherapy and photothermal therapy of PC10A/DOX/HAuNS hydrogels could significantly improve the therapeutic effect. Therefore, the multifunctional hydrogel PC10A/DOX/HAuNS is promising to provide a new strategy for sustained chemo-photothermal therapy.

An injectable hybrid hydrogel based on a genetically engineered polypeptide for second near-infrared fluorescence/photoacoustic imaging-monitored sustained chemo-photothermal therapy.

An injectable multifunctional hydrogel based on an engineered coiled-coil polypeptide, Ag2S quantum dots (QDs), and paclitaxel (PTX) has been developed for sustained chemo-photothermal therapy. Oil-soluble Ag2S QDs and PTX were first loaded into nanogels formed with engineered polypeptide PC10A by ultrasonic treatment to prepare PC10A/Ag2S QD/PTX nanogels. The multifunctional PC10A/Ag2S QD/PTX hydrogels were prepared by dissolving the PC10A/Ag2S QD/PTX nanogels into the PC10A hydrogel. The PC10A/Ag2S QD/PTX hydrogel can be injected directly into the site of tumors. In vitro and in vivo toxicity results showed that the PC10A/Ag2S QD/PTX hydrogel presented excellent biocompatibility. Compared with single near-infrared photothermal therapy and chemotherapy, the combined therapy could effectively suppress the growth of SKOV3 ovarian carcinoma tumor. In addition, real-time monitoring of the in vivo degradation of the PC10A/Ag2S QD/PTX hydrogel was achieved by near-infrared fluorescence imaging and photoacoustic imaging. These results demonstrated that this injectable multifunctional PC10A/Ag2S QD/PTX hydrogel has the potential as a theranostic platform for sustained cancer treatments.

In situ aqueous synthesis of genetically engineered polypeptide-capped Ag2S quantum dots for second near-infrared fluorescence/photoacoustic imaging and photothermal therapy.

Ag2S quantum dots have received extensive attention as theranostic agents for second near-infrared (NIR-II) fluorescence and photoacoustic dual-mode imaging, and photothermal therapy. However, it is still greatly challenging to synthesize Ag2S quantum dots using aqueous synthesis. In this study, genetically engineered polypeptide-capped Ag2S quantum dots were successfully synthesized. Three cysteines were integrated to the C-terminal and N-terminal of RGDPC10A to enhance the stability and brightness of the synthesized Ag2S quantum dots. The RGDPC10A-capped Ag2S quantum dots exhibited excellent stability, outstanding resistance to photobleaching, and a superior quantum yield of up to 3.78% in the NIR-II biological window. The in vitro and in vivo results showed that the RGDPC10A-capped Ag2S quantum dots possessed typical NIR-II fluorescence, photoacoustic imaging, and photothermal therapeutic effectiveness against tumors. Moreover, the results of toxicity assays suggested that the RGDPC10A-capped Ag2S quantum dots have negligible long-term toxicity. These findings open up the possibility for synthesizing theranostic agents by using this aqueous method.

High quantum yield Ag2S quantum dot@polypeptide-engineered hybrid nanogels for targeted second near-infrared fluorescence/photoacoustic imaging and photothermal therapy.

A high quantum yield (4.3%) hybrid nanogel system based on engineered polypeptides and Ag2S quantum dots has been developed as a multifunctional diagnostic and therapeutic agent for targeted second near-infrared fluorescence, photoacoustic imaging, and photothermal therapy.