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Since its introduction 20 years ago for the treatment of chronic wounds, negative pressure wound therapy use has expanded to a variety of other wound types. Various mechanisms of action for its efficacy in wound healing have been postulated, but no unifying theory exists. Proposed mechanisms include induction of perfusion changes, microdeformation, macrodeformation, exudate control and decreasing the bacterial load in the wound. We surmise that these different mechanisms have varying levels of dominance in each wound type. Specifically, negative pressure wound therapy is beneficial to acute open wounds because it induces perfusion changes and formation of granulation tissue. Post-surgical incisional wounds are positively affected by perfusion changes and exudate control. In the context of chronic wounds, negative pressure wound therapy removes harmful and corrosive substances within the wounds to affect healing. When skin grafts and dermal substitutes are used to close a wound, negative pressure wound therapy is effective in promoting granulation tissue formation, controlling exudate and decreasing the bacterial load in the wound. In this review, we elucidate some of the mechanisms behind the positive wound healing effects of negative pressure wound therapy, providing possible explanations for these effects in different wound types.

Burn wound conversion describes the process by which superficial partial thickness burns convert into deeper burns necessitating surgical intervention. Fully understanding and thus controlling this phenomenon continues to defy burn surgeons. However, potentially guiding burn wound progression so as to obviate the need for surgery while still bringing about healing with limited scarring is the major unmet challenge. Comprehending the pathophysiologic background contributing to deeper progression of these burns is an essential prerequisite to planning any intervention. In this study, a review of articles examining burn wound progression over the last five years was conducted to analyze trends in recent burn progression research, determine changes in understanding of the pathogenesis of burn conversion, and subsequently examine the direction for future research in developing therapies. The majority of recent research focuses on applying therapies from other disease processes to common underlying pathogenic mechanisms in burn conversion. While ischemia, inflammation, and free oxygen radicals continue to demonstrate a critical role in secondary necrosis, novel mechanisms such as autophagy have also been shown to contribute affect significantly burn progression significantly. Further research will have to determine whether multiple mechanisms should be targeted when developing clinical therapies.

Adipose-derived stem cells (ADSCs) are a subset of mesenchymal stem cells (MSCs) that possess many of the same regenerative properties as other MSCs. However, the ubiquitous presence of ADSCs and their ease of access in human tissue have led to a burgeoning field of research. The plastic surgeon is uniquely positioned to harness this technology because of the relative frequency in which they perform procedures such as liposuction and autologous fat grafting. This review examines the current landscape of ADSC isolation and identification, summarizes the current applications of ADSCs in the field of plastic surgery, discusses the risks associated with their use, current barriers to universal clinical translatability, and surveys the latest research which may help to overcome these obstacles.

Up to 15 billion dollars of US health care expenditure each year is consumed by treatment of poorly healing wounds whose etiologies are often associated with aberrancies in tissue oxygenation. To address this issue, several modes of tissue oxygen delivery systems exist, including Hyperbaric Oxygen Therapy (HBOT) and Topical Oxygen Therapy (TOT), but their efficacies have yet to be fully substantiated. Micro/nanobubbles (MNBs), which range anywhere from 100 μm to <1 μm in diameter and are relatively stable for hours, offer a new mode of oxygen delivery to wounds. The aim of this article is to systematically review literature examining the use of TOT for wound healing and use of MNBs for tissue oxygenation using the MEDLINE database. The search yielded 87 articles (12 MNB articles and 75 TOT articles), of which 52 met the inclusion criteria for this literature review (12 MNB articles and 40 TOT articles). Additionally, we present an analysis on the efficacy of our MNB generating technology and propose its use as a wound healing agent.

Scarring following burn injury and its accompanying aesthetic and functional sequelae still pose major challenges. Hypertrophic scarring (HTS) can greatly impact patients’ quality of life related to appearance, pain, pruritus and even loss of function of the injured body region. The identification of molecular events occurring in the evolution of the burn scar has increased our knowledge; however, this information has not yet translated into effective treatment modalities. Although many of the pathophysiologic pathways that bring about exaggerated scarring have been identified, certain nuances in burn scar formation are starting to be recognized. These include the effects of neurogenic inflammation, mechanotransduction, and the unique interactions of burn wound fluid with fat tissue in the deeper dermal layers, all of which may influence scarring outcome. Tension on the healing scar, pruritus, and pain all induce signaling pathways that ultimately result in increased collagen formation and myofibroblast phenotypic changes. Exposure of the fat domes in the deep dermis is associated with increased HTS, possibly on the basis of altered interaction of adipose-derived stem cells and the deep burn exudate. These pathophysiologic patterns related to stem cell-cytokine interactions, mechanotransduction, and neurogenic inflammation can provide new avenues of exploration for possible therapeutic interventions.

Adipogenesis is a complex process whereby the multipotent adipose-derived stem cell is converted to a preadipocyte before terminal differentiation into the mature adipocyte. Preadipocytes are present throughout adult life, exhibit adipose fat depot specificity, and differentiate and proliferate from distinct progenitor cells. The mechanisms that promote preadipocyte commitment and maturation involve numerous protein factor regulators, epigenetic factors, and miRNAs. Detailed characterization of this process is currently an area of intense research and understanding the roles of preadipocytes in tissue plasticity may provide insight into novel approaches for tissue engineering, regenerative medicine and treating a host of obesity-related conditions. In the current study, we analyzed the current literature and present a review of the characteristics of transitioning adipocytes and detail how local microenvironments influence their progression towards terminal differentiation and maturation. Specifically, we detail the characterization of preadipocyte via surface markers, examine the signaling cascades and regulation behind adipogenesis and cell maturation, and survey their role in tissue plasticity and health and disease.