Treatment of full-thickness skin defects poses significant clinical challenges including risk of infection and severe scaring. Silver nanoparticle (NAg), an effective antimicrobial agent, has provided a promising therapeutic method for burn wounds. However, the detailed mechanism remains unknown. Hence, we constructed a metallic nanosilver particles-collagen/chitosan hybrid scaffold (NAg-CCS) and investigated its potential effects on wound healing. In vitro scratch assay, immunofluorescence staining and antibacterial activity of the scaffold were all studied. In vivo NAg-CCS was applied in full-thickness skin defects in Sprague-Dawley (SD) rats and the therapeutic effects of treatment were evaluated. The results showed that NAg at a concentration of 10 ppm accelerated the migration of fibroblasts with an increase in expression of α-smooth muscle actin (α-SMA). Furthermore, in vivo studies showed increased levels of pro-inflammatory and scar-related factors as well as α-SMA, while markers for macrophage activation were up-regulated. On day 60 post transplantation of ultra-thin skin graft, the regenerated skin by NAg-CCS had a similar structure to normal skin. In summary, we demonstrated that NAg-CCS was bactericidal, anti-inflammatory and promoted wound healing potentially by regulating fibroblast migration and macrophage activation, making it an ideal dermal substitute for wound regeneration.

Critical tissue defects frequently result from trauma, burns, chronic wounds and/or surgery. The ideal treatment for such tissue loss is autografting, but donor sites are often limited. Tissue engineering (TE) is an inspiring alternative for tissue repair and regeneration (TRR). One of the current state-of-the-art methods for TRR is gene therapy. Non-viral gene delivery systems (nVGDS) have great potential for TE and have several advantages over viral delivery including lower immunogenicity and toxicity, better cell specificity, better modifiability, and higher productivity. However, there is no ideal nVGDS for TRR, hence, there is widespread research to improve their properties. This review introduces the basic principles and key aspects of commonly-used nVGDSs. We focus on recent advances in their applications, current challenges, and future directions.

Abstract. Skin perfusion pressure (SPP) is the blood pressure that is the requisite for the restoration of microcirculatory or capillary flow following controlled occlusion and subsequent flow return. The purpose of the current review was to evaluate the value of SPP for the prediction of wound healing in patients with limb ischemia. Articles published up to January 31, 2017 were searched in the PubMed database and Chinese database CNKI, using the keywords of 'skin perfusion pressure', 'limb ischemia' and 'wound healing'. Articles were obtained and reviewed to analyze the predictive value of SPP with regard to the healing potential of ischemia wounds on limbs. Three different types of techniques are currently used for the measurement of SPP, namely radioisotope clearance, photoplethysmography and laser Doppler, with laser Doppler as the most widely applied technique, due to its noninvasiveness and ease of operability. SPP may effectively assess wound healing potential in ischemic limbs with high sensitivity and specificity; however, its optimum cut-off point remains uncertain. Compared with other noninvasive microcirculatory assessment tools including ankle-brachial index, toe blood pressure and transcutaneous oxygen pressure, SPP has its advantages including that it is not affected by vascular calcification, anatomical structure or patient condition. In conclusion, SPP may be used as an index to accurately predict wound healing in patients with limb ischemia. However, it is difficult to determine the optimum cut-off of SPP due to the limitations of current data. Further study is necessary to confirm the optimum cut-off value of SPP in predicting wound healing potential.

No abstract

No abstract