An ultrathin poly(l-lactic acid) nanosheet as a burn wound dressing for protection against bacterial infection

Comparative results of autologous skin cell suspension combined with a contact layer dressing versus autologous skin cell suspension and a poly-lactic acid dressing in larger total body surface burns

INTRODUCTION

Contact layer dressing (CLD) is standard after autologous skin cell suspension (ASCS); however, the authors wondered whether a poly-lactic acid dressing (PLAD) results in superior outcomes and cost savings.

MATERIAL AND METHODS

Retrospective cohort study including greater than 10% total body surface area (TBSA) burns treated with ASCS and either PLAD or CLD. Primary outcomes were infection and length of stay (LOS).

RESULTS

71 patients (76% male, 24% pediatric, mean age 37 years) were included. Twenty-eight patients (39%) received CLD and 43 (61%) received PLAD. Wound infections were decreased in PLAD (7 vs 32%, p = 0.009). When controlling for area grafted (cm2) and TBSA, logistic regression revealed odds of post-operative infection was 8.1 times higher in CLD (p = 0.015). PLAD required antibiotics for fewer days (mean 0.47 vs 4.39, p = 0.0074) and shorter LOS (mean 17 vs 29 days, p < 0.001). Mean adjusted charges per %TBSA was $18,459 in PLAD vs. $25,397 in CLD (p = 0.0621).

CONCLUSION

In the first analysis of its kind, this study showed polylactic acid dressing combined with autologous skin cell suspension led to a decrease in postoperative infections, length of hospital stay, and total patient charges.

Alloplastic Epidermal Skin Substitute in the Treatment of Burns

The goal of burn wound treatment is to ensure rapid epithelialization in superficial burns and the process of rebuilding the lost skin in deep burns. Topical treatment plays an important role. One of the innovations in the field of synthetic materials dedicated to the treatment of burns is epidermal skin substitutes. Since the introduction of Suprathel®, the alloplastic epidermal substitute, many research results have been published in which the authors investigated the properties and use of this substitute in the treatment of wounds of various origins, including burn wounds. Burn wounds cause both physical and psychological discomfort, which is why ensuring comfort during treatment is extremely important. Alloplastic epidermal substitute, due to its biodegradability, plasticity, no need to remove the dressing until healing, and the associated reduction in pain, is an alternative for treating burns, especially in children.

Self-Standing Nanomembranes of Super-Tough Plastics

Nanomembranes are effective coating materials for protecting substrates from external stimuli; however, they are generally not self-standing owing to their low mechanical toughness. Self-standing nanomembranes would be an innovative development in the field of nanotechnology including miniaturized devices. In this study, self-standing nanomembranes were developed by spin-casting supertough polyamides over dimethylformamide solution. The polyamides were synthesized by the polycondensation of two derivatives of 4,4'-diamino-α-truxillic acid (4ATA) with slightly bent diphenylcyclobutane in the core. Mechanical evaluation of the 4ATA polyamides having an appropriate composition of aliphatic diacids revealed a high strain-energy density of 231 MJ m^-3 at its maximum, which is significantly tougher than spider silk. The nanocoats with a thickness of several hundred nanometers showing interference fringes were able to be peeled off the glass substrate without breaking, owing to its ultrahigh toughness. The self-standing nanomembrane would be applied to flexible devices in the future.

Nanoengineered therapeutic scaffolds for burn wound management

BACKGROUND

Wound healing is a complex process, and selecting an appropriate treatment is crucial and varies from one wound to another. Among injuries, burn wounds are more challenging to treat. Different dressings and scaffolds come into play when skin is injured. These scaffolds provide the optimum environment for wound healing. With the advancements of nanoengineering, scaffolds have been engineered to improve wound healing with lower fatality rates.

OBJECTIVES

Nanoengineered systems have emerged as one of the promising candidates for burn wound management. This review paper aims to provide an in-depth understanding of burn wounds and the role of nanoengineering in burn wound management. The advantages of nanoengineered scaffolds, their properties, and their proven effectiveness have been discussed. Nanoparticles and nanofibers-based nanoengineered therapeutic scaffolds provide optimum protection, infection management, and accelerated wound healing due to their unique characteristics. These scaffolds increase cell attachment and proliferation for desired results.

RESULTS

The literature review suggested that the utilization of nanoengineered scaffolds has accelerated burn wound healing. Nanofibers provide better cell attachment and proliferation among different nanoengineered scaffolds due to their 3D structure mimics the body's extracellular matrix.

CONCLUSION

With the application of these advanced nanoengineered scaffolds, better burn wound management is possible due to sustained drug delivery, better cell attachment, and an infection-free environment.

Conductive Materials for Healing Wounds: Their Incorporation in Electroactive Wound Dressings, Characterization, and Perspectives

The use of conductive materials to promote the activity of electrically responsive cells is an effective means of accelerating wound healing. This article focuses on recent advancements in conductive materials, with emphasis on overviewing their incorporation with non-conducting polymers to fabricate electroactive wound dressings. The characteristics of these electroactive dressings are deliberated, and the mechanisms on how they accelerate the wound healing process are discussed. Potential directions for the future development of electroactive wound dressings and their potential in monitoring the course of wound healing in vivo concomitantly are also proposed.

Fabrication and characterization of ultrathin spin-coated poly(L-lactic acid) films suitable for cell attachment and curcumin loading

In the present study, ultrathin poly(L-lactic acid) (PLLA) films were fabricated using the spin-coating technique. Physicochemical properties of the formed materials, including their morphology, thickness, transparency, and contact angle, have been studied. We determined that the morphology of PLLA films could be regulated by changing the polymer concentration and humidity. By altering the humidity, microporous and flat PLLA films can be fabricated. The obtained samples were subsequently used for culturing mesenchymal stem cells and fibroblasts. It has been determined that cells effectively adhered to prepared films and formed on them a monolayer culture with high viability. It has been shown that PLLA films are suitable for the entrapment of curcumin (up to 12.1 μm cm^-2) and provide its sustained release in solutions isotonic to blood plasma. The obtained PLLA films appear to be prospective materials for potential application in regenerative medicine as part of cell-containing tissue engineered dressings for chronic wound treatment.

Efficient differentiation and polarization of primary cultured neurons on poly(lactic acid) scaffolds with microgrooved structures

Synthetic biodegradable polymers including poly(lactic acid) (PLA) are attractive cell culture substrates because their surfaces can be micropatterned to support cell adhesion. The cell adhesion properties of a scaffold mainly depend on its surface chemical and structural features; however, it remains unclear how these characteristics affect the growth and differentiation of cultured cells or their gene expression. In this study, we fabricated two differently structured PLA nanosheets: flat and microgrooved. We assessed the growth and differentiation of mouse primary cultured cortical neurons on these two types of nanosheets after pre-coating with poly-D-lysine and vitronectin. Interestingly, prominent neurite bundles were formed along the grooves on the microgrooved nanosheets, whereas thin and randomly extended neurites were only observed on the flat nanosheets. Comparative RNA sequencing analyses revealed that the expression of genes related to postsynaptic density, dendritic shafts, and asymmetric synapses was significantly and consistently up-regulated in cells cultured on the microgrooved nanosheets when compared with those cultured on the flat nanosheets. These results indicate that microgrooved PLA nanosheets can provide a powerful means of establishing a culture system for the efficient and reproducible differentiation of neurons, which will facilitate future investigations of the molecular mechanisms underlying the pathogenesis of neurological disorders.

Current status and future outlook of nano-based systems for burn wound management

Wound healing process is a natural and intricate response of the body to its injuries and includes a well-orchestrated sequence of biochemical and cellular phenomena to restore the integrity of skin and injured tissues. Complex nature and associated complications of burn wounds lead to an incomplete and prolonged recovery of these types of wounds. Among different materials and systems which have been used in treating the wounds, nanotechnology driven therapeutic systems showed a great opportunity to improvement and enhancement of the healing process of different type of wounds. The aim of this study is to provide an overview of the recent studies about the various nanotechnology-based management of burn wounds and the future outlook of these systems in this area. Laboratory and animal models for assessing the efficacy of these systems in burn wound management also discussed.