RESUMEN
Wound healing is one of the most complex processes in the human body. It involves the spatial and temporal synchronization of a variety of cell types with distinct roles in the phases of hemostasis, inflammation, growth, re-epithelialization, and remodeling. With the evolution of single cell technologies, it has been possible to uncover phenotypic and functional heterogeneity within several of these cell types. There have also been discoveries of rare, stem cell subsets within the skin, which are unipotent in the uninjured state, but become multipotent following skin injury. Unraveling the roles of each of these cell types and their interactions with each other is important in understanding the mechanisms of normal wound closure. Changes in the microenvironment including alterations in mechanical forces, oxygen levels, chemokines, extracellular matrix and growth factor synthesis directly impact cellular recruitment and activation, leading to impaired states of wound healing. Single cell technologies can be used to decipher these cellular alterations in diseased states such as in chronic wounds and hypertrophic scarring so that effective therapeutic solutions for healing wounds can be developed.
Asunto(s)
Matriz Extracelular/metabolismo , Hemostasis/fisiología , Neovascularización Fisiológica/fisiología , Cicatrización de Heridas/fisiología , Animales , Plaquetas/metabolismo , Humanos , Piel/metabolismo , Piel/patologíaRESUMEN
Topical patch delivery of deferoxamine (DFO) has been studied as a treatment for this fibrotic transformation in irradiated tissue. Efficacy of a novel cream formulation of DFO was studied as a RIF therapeutic in unwounded and excisionally wounded irradiated skin. C57BL/6J mice underwent 30 Gy of radiation to the dorsum followed by 4 weeks of recovery. In a first experiment, mice were separated into six conditions: DFO 50 mg cream (D50), DFO 100 mg cream (D100), soluble DFO injections (DI), DFO 1 mg patch (DP), control cream (Vehicle), and irradiated untreated skin (IR). In a second experiment, excisional wounds were created on the irradiated dorsum of mice and then divided into four treatment groups: DFO 100 mg Cream (W-D100), DFO 1 mg patch (W-DP), control cream (W-Vehicle), and irradiated untreated wounds (W-IR). Laser Doppler perfusion scans, biomechanical testing, and histological analysis were performed. In irradiated skin, D100 improved perfusion compared to D50 or DP. Both D100 and DP enhanced dermal characteristics, including thickness, collagen density and 8-isoprostane staining compared to untreated irradiated skin. D100 outperformed DP in CD31 staining, indicating higher vascular density. Extracellular matrix features of D100 and DP resembled normal skin more closely than DI or control. In radiated excisional wounds, D100 facilitated faster wound healing and increased perfusion compared to DP. The 100 mg DFO cream formulation rescued RIF of unwounded irradiated skin and improved excisional wound healing in murine skin relative to patch delivery of DFO.
Asunto(s)
Deferoxamina , Síndrome de Fibrosis por Radiación , Ratones , Animales , Ratones Endogámicos C57BL , Deferoxamina/farmacología , Deferoxamina/uso terapéutico , Piel , PerfusiónRESUMEN
Cells and tissue within injured organs undergo a complicated healing process that still remains poorly understood. Interestingly, smaller organisms respond to injury with tissue regeneration and restoration of function, while humans and other large organisms respond to injury by forming dysfunctional, fibrotic scar tissue. Over the past few decades, allometric scaling principles have been well established to show that larger organisms experience exponentially higher tissue forces during movement and locomotion and throughout the organism's lifespan. How these evolutionary adaptations may affect tissue injury has not been thoroughly investigated in humans. We discuss how these adapations may affect healing and demonstrate that blocking the most evolutionary conserved biologic force sensor enables large organisms to heal after injury with true tissue regeneration. Future strategies to disrupt tissue force sensors may unlock the key to regenerating after injury in a wide range of organ systems.
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Evolución Biológica , Cicatrización de Heridas , Humanos , LocomociónRESUMEN
In the skin, tissue injury results in fibrosis in the form of scars composed of dense extracellular matrix deposited by fibroblasts. The therapeutic goal of regenerative wound healing has remained elusive, in part because principles of fibroblast programming and adaptive response to injury remain incompletely understood. Here, we present a multimodal -omics platform for the comprehensive study of cell populations in complex tissue, which has allowed us to characterize the cells involved in wound healing across both time and space. We employ a stented wound model that recapitulates human tissue repair kinetics and multiple Rainbow transgenic lines to precisely track fibroblast fate during the physiologic response to skin injury. Through integrated analysis of single cell chromatin landscapes and gene expression states, coupled with spatial transcriptomic profiling, we are able to impute fibroblast epigenomes with temporospatial resolution. This has allowed us to reveal potential mechanisms controlling fibroblast fate during migration, proliferation, and differentiation following skin injury, and thereby reexamine the canonical phases of wound healing. These findings have broad implications for the study of tissue repair in complex organ systems.
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Cicatriz/patología , Fibroblastos/metabolismo , Fibrosis/patología , Piel/lesiones , Cicatrización de Heridas/fisiología , Animales , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Matriz Extracelular/metabolismo , Femenino , Mecanotransducción Celular/fisiología , Ratones , Ratones Endogámicos C57BL , Piel/metabolismoRESUMEN
The aim of this study was to further elucidate the molecular mechanisms that mediate pathologic foreign body response (FBR) to biomedical implants. The longevity of biomedical implants is limited by the FBR, which leads to implant failure and patient morbidity. Since the specific molecular mechanisms underlying fibrotic responses to biomedical implants have yet to be fully described, there are currently no targeted approaches to reduce pathologic FBR. We utilized proteomics analysis of human FBR samples to identify potential molecular targets for therapeutic inhibition of FBR. We then employed a murine model of FBR to further evaluate the role of this potential target. We performed histological and immunohistochemical analysis on the murine FBR capsule tissue, as well as single-cell RNA sequencing (scRNA-seq) on cells isolated from the capsules. We identified IQ motif containing GTPase activating protein 1 (IQGAP1) as the most promising of several targets, serving as a central molecular mediator in human and murine FBR compared to control subcutaneous tissue. IQGAP1-deficient mice displayed a significantly reduced FBR compared to wild-type mice as evidenced by lower levels of collagen deposition and maturity. Our scRNA-seq analysis revealed that decreasing IQGAP1 resulted in diminished transcription of mechanotransduction, inflammation, and fibrosis-related genes, which was confirmed on the protein level with immunofluorescent staining. The deficiency of IQGAP1 significantly attenuates FBR by deactivating downstream mechanotransduction signaling, inflammation, and fibrotic pathways. IQGAP1 may be a promising target for rational therapeutic design to mitigate pathologic FBR around biomedical implants.
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Materiales Biocompatibles/efectos adversos , Cuerpos Extraños/inmunología , Prótesis e Implantes/efectos adversos , Transducción de Señal/inmunología , Proteínas Activadoras de ras GTPasa/inmunología , Animales , Colágeno/inmunología , Fibrosis/inmunología , Humanos , Inflamación/inmunología , Masculino , Mecanotransducción Celular/inmunología , Ratones , Ratones Endogámicos C57BL , Transcripción Genética/inmunologíaRESUMEN
BACKGROUND: In recent decades, the use of near-infrared light and fluorescence-guidance during open and laparoscopic surgery has exponentially expanded across various clinical settings. However, tremendous variability exists in how it is performed. OBJECTIVE: In this first published survey of international experts on fluorescence-guided surgery, we sought to identify areas of consensus and nonconsensus across 4 areas of practice: fundamentals; patient selection/preparation; technical aspects; and effectiveness and safety. METHODS: A Delphi survey was conducted among 19 international experts in fluorescence-guided surgery attending a 1-day consensus meeting in Frankfurt, Germany on September 8th, 2019. Using mobile phones, experts were asked to anonymously vote over 2 rounds of voting, with 70% and 80% set as a priori thresholds for consensus and vote robustness, respectively. RESULTS: Experts from 5 continents reached consensus on 41 of 44 statements, including strong consensus that near-infrared fluorescence-guided surgery is both effective and safe across a broad variety of clinical settings, including the localization of critical anatomical structures like vessels, detection of tumors and sentinel nodes, assessment of tissue perfusion and anastomotic leaks, delineation of segmented organs, and localization of parathyroid glands. Although the minimum and maximum safe effective dose of ICG were felt to be 1 to 2âmg and >10âmg, respectively, there was strong consensus that determining the optimum dose, concentration, route and timing of ICG administration should be an ongoing research focus. CONCLUSIONS: Although fluorescence imaging was almost unanimously perceived to be both effective and safe across a broad range of clinical settings, considerable further research remains necessary to optimize its use.
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Verde de Indocianina , Ganglio Linfático Centinela , Consenso , Técnica Delphi , Humanos , Imagen Óptica/métodosRESUMEN
BACKGROUND: Radiation-induced skin injury is a well-known risk factor for impaired wound healing. Over time, the deleterious effects of radiation on skin produce a fibrotic, hypovascular dermis poorly suited to wound healing. Despite increasing understanding of the underlying pathophysiology, therapeutic options remain elusive. Deferoxamine (DFO), an iron-chelating drug, has been shown in prior murine studies to ameliorate radiation-induced skin injury as well as improve wound healing outcomes in various pathologic conditions when administered transdermally. In this preclinical study, we evaluated the effects of deferoxamine on wound healing outcomes in chronically irradiated murine skin. METHODS: Wild-type mice received 30 Gy of irradiation to their dorsal skin and were left to develop chronic fibrosis. Stented excisional wounds were created on their dorsal skin. Wound healing outcomes were compared across 4 experimental conditions: DFO patch treatment, vehicle-only patch treatment, untreated irradiated wound, and untreated nonirradiated wounds. Gross closure rate, wound perfusion, scar elasticity, histology, and nitric oxide assays were compared across the conditions. RESULTS: Relative to vehicle and untreated irradiated wounds, DFO accelerated wound closure and reduced the frequency of healing failure in irradiated wounds. DFO augmented wound perfusion throughout healing and upregulated angiogenesis to levels observed in nonirradiated wounds. Histology revealed DFO increased wound thickness, collagen density, and improved collagen fiber organization to more closely resemble nonirradiated wounds, likely contributing to the observed improved scar elasticity. Lastly, DFO upregulated inducible nitric oxide synthase and increased nitric oxide production in early healing wounds. CONCLUSION: Deferoxamine treatment presents a potential therapeutic avenue through which to target impaired wound healing in patients following radiotherapy.
Asunto(s)
Deferoxamina , Traumatismos por Radiación , Animales , Cicatriz/patología , Colágeno/farmacología , Deferoxamina/farmacología , Deferoxamina/uso terapéutico , Humanos , Ratones , Óxido Nítrico , Piel/patología , Cicatrización de HeridasRESUMEN
Due to the need for more information about Department of Defense sponsored wound healing research, the Wound Healing Foundation initiated the writing of this article. It briefly describes the Vision, Mission and Goals of the Department of Defense Strategic Medical Research Plan. It also describes the current objectives of Department of Defense research funding and where to access this information in detail. The grant cycle, the timing of request for proposals and some of the specifics of their requirements are also mentioned. A brief discussion of budgeting and overhead is also included.
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Investigación Biomédica , Cicatrización de Heridas , Proyectos de Investigación , EscrituraRESUMEN
Biological scaffolds such as hydrogels provide an ideal, physio-mimetic of native extracellular matrix (ECM) that can improve wound healing outcomes after cutaneous injury. While most studies have focused on the benefits of hydrogels in accelerating wound healing, there are minimal data directly comparing different hydrogel material compositions. In this study, we utilized a splinted excisional wound model that recapitulates human-like wound healing in mice and treated wounds with three different collagen hydrogel dressings. We assessed the feasibility of applying each dressing and performed histologic and histopathologic analysis on the explanted scar tissues to assess variations in collagen architecture and alignment, as well as the tissue response. Our data indicate that the material properties of hydrogel dressings can significantly influence healing time, cellular response, and resulting architecture of healed scars. Specifically, our pullulan-collagen hydrogel dressing accelerated wound closure and promoted healed tissue with less dense, more randomly aligned, and shorter collagen fibres. Further understanding of how hydrogel properties affect the healing and resulting scar architecture of wounds may lead to novel insights and further optimization of the material properties of wound dressings.
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Hidrogeles , Cicatrización de Heridas , Animales , Vendajes , Cicatriz , Colágeno/farmacología , Glucanos , Hidrogeles/farmacología , RatonesRESUMEN
The Wound Healing Foundation (WHF) recognised a need for an unbiased consensus on the best treatment of chronic wounds. A panel of 13 experts were invited to a virtual meeting which took place on 27 March 2021. The proceedings were organised in the sub-sections diagnosis, debridement, infection control, dressings, grafting, pain management, oxygen treatment, outcomes and future needs. Eighty percent or better concurrence among the panellists was considered a consensus. A large number of critical questions were discussed and agreed upon. Important takeaways included that wound care needs to be simplified to a point that it can be delivered by the patient or the patient's family. Another one was that telemonitoring, which has proved very useful during the COVID-19 pandemic, can help reduce the frequency of interventions by a visiting nurse or a wound care center. Defining patient expectations is critical to designing a successful treatment. Patient outcomes might include wound specific outcomes such as time to heal, wound size reduction, as well as improvement in quality of life. For those patients with expectations of healing, an aggressive approach to achieve that goal is recommended. When healing is not an expectation, such as in patients receiving palliative wound care, outcomes might include pain reduction, exudate management, odour management and/or other quality of life benefits to wound care.
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COVID-19 , Cicatrización de Heridas , COVID-19/terapia , Consenso , Humanos , Pandemias , Calidad de VidaRESUMEN
The iron chelator, deferoxamine (DFO), has been shown to potentially improve dermal radiation-induced fibrosis (RIF) in mice through increased angiogenesis and reduced oxidative damage. This preclinical study evaluated the efficacy of two DFO administration modalities, transdermal delivery and direct injection, as well as temporal treatment strategies in relation to radiation therapy to address collateral soft tissue fibrosis. The dorsum of CD-1 nude mice received 30 Gy radiation, and DFO (3 mg) was administered daily via patch or injection. Treatment regimens were prophylactic, during acute recovery, post-recovery, or continuously throughout the experiment (n = 5 per condition). Measures included ROS-detection, histology, biomechanics and vascularity changes. Compared with irradiated control skin, DFO treatment decreased oxidative damage, dermal thickness and collagen content, and increased skin elasticity and vascularity. Metrics of improvement in irradiated skin were most pronounced with continuous transdermal delivery of DFO. In summary, DFO administration reduces dermal fibrosis induced by radiation. Although both treatment modalities were efficacious, the transdermal delivery showed greater effect than injection for each temporal treatment strategy. Interestingly, the continuous patch group was more similar to normal skin than to irradiated control skin by most measures, highlighting a promising approach to address detrimental collateral soft tissue injury following radiation therapy.
Asunto(s)
Deferoxamina/farmacología , Dermis/metabolismo , Dermis/patología , Dermis/efectos de la radiación , Radiación Ionizante , Animales , Biomarcadores , Dermis/irrigación sanguínea , Susceptibilidad a Enfermedades , Femenino , Fibrosis , Ratones , Microvasos/diagnóstico por imagen , Microvasos/metabolismo , Estrés Oxidativo , Síndrome de Fibrosis por Radiación/etiología , Síndrome de Fibrosis por Radiación/metabolismo , Síndrome de Fibrosis por Radiación/patología , Especies Reactivas de Oxígeno/metabolismoRESUMEN
OBJECTIVE: The aim of this study was to determine the interaction of full thickness excisional wounds and tumors in vivo. SUMMARY OF BACKGROUND DATA: Tumors have been described as wounds that do not heal due to similarities in stromal composition. On the basis of observations of slowed tumor growth after ulceration, we hypothesized that full thickness excisional wounds would inhibit tumor progression in vivo. METHODS: To determine the interaction of tumors and wounds, we developed a tumor xenograft/allograft (human head and neck squamous cell carcinoma SAS/mouse breast carcinoma 4T1) wound mouse model. We examined tumor growth with varying temporospatial placement of tumors and wounds or ischemic flap. In addition, we developed a tumor/wound parabiosis model to understand the ability of tumors and wounds to recruit circulating progenitor cells. RESULTS: Tumor growth inhibition by full thickness excisional wounds was dose-dependent, maintained by sequential wounding, and relative to distance. This effect was recapitulated by placement of an ischemic flap directly adjacent to a xenograft tumor. Using a parabiosis model, we demonstrated that a healing wound was able to recruit significantly more circulating progenitor cells than a growing tumor. Tumor inhibition by wound was unaffected by presence of an immune response in an immunocompetent model using a mammary carcinoma. Utilizing functional proteomics, we identified 100 proteins differentially expressed in tumors and wounds. CONCLUSION: Full thickness excisional wounds have the ability to inhibit tumor growth in vivo. Further research may provide an exact mechanism for this remarkable finding and new advances in wound healing and tumor biology.
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Neoplasias/patología , Úlcera/patología , Heridas y Lesiones/patología , Animales , Femenino , Ratones , Neoplasias/complicaciones , Úlcera/complicaciones , Heridas y Lesiones/complicacionesRESUMEN
BACKGROUND: Staged implant-based breast reconstruction is the most common reconstructive modality following mastectomy. Postoperative implant infections can have a significant impact on adjuvant oncologic care and reconstructive outcome. Here, we investigate the impact of ß-lactam antibiotics (i.e., bactericidal) compared to alternative antibiotic agents on postoperative outcomes for implant-based breast reconstruction. METHODS: A retrospective analysis of patients who underwent immediate sub-pectoral tissue expander placement with an inferior acellular dermal matrix (ADM) sling at a single institution between May 2008 and July 2018 was performed. Patient demographics, comorbidities, and complication rates were retrieved. The impact of antibiotic regimen on postoperative outcomes, including infection rate and reconstructive failure, was investigated. RESULTS: A total of 320 patients with a mean age and BMI of 48.2 years and 25.0 kg/m2 , respectively, who underwent 542 immediate breast reconstructions were included in the study. The use of a ß-lactam antibiotic was protective against postoperative infection (odds ratio [OR] = 0.467, p = .046), infection requiring operative management (OR = 0.313, p = .022), and reconstructive failure (OR = 0.365, p = .028). Extended, that is, post-discharge, prophylaxis was not associated with any clinical benefit. CONCLUSION: The use of ß-lactam antibiotics for pre-/peri-operative prophylaxis is superior to alternative antibiotics with a bacteriostatic mechanism of action regarding rates of postoperative infection and reconstructive failure following immediate tissue expander-based breast reconstruction. Extended, that is, post-discharge, prophylaxis does not appear to be indicated, regardless of the antibiotic chosen.
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Neoplasias de la Mama/cirugía , Mamoplastia/efectos adversos , Mastectomía/efectos adversos , Complicaciones Posoperatorias/tratamiento farmacológico , Infección de la Herida Quirúrgica/tratamiento farmacológico , Dispositivos de Expansión Tisular/efectos adversos , beta-Lactamas/farmacología , Cuidados Posteriores , Profilaxis Antibiótica/métodos , Neoplasias de la Mama/patología , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/patología , Pronóstico , Estudios Retrospectivos , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/patologíaRESUMEN
Intravenous infusion of mesenchymal stromal cells (MSCs) is thought to be a viable treatment for numerous disorders. Although the intrinsic immunosuppressive ability of MSCs has been credited for this therapeutic effect, their exact impact on endogenous tissue-resident cells following delivery has not been clearly characterized. Moreover, multiple studies have reported pulmonary sequestration of MSCs upon intravenous delivery. Despite substantial efforts to improve MSC homing, it remains unclear whether MSC migration to the site of injury is necessary to achieve a therapeutic effect. Using a murine excisional wound healing model, we offer an explanation of how sequestered MSCs improve healing through their systemic impact on macrophage subpopulations. We demonstrate that infusion of MSCs leads to pulmonary entrapment followed by rapid clearance, but also significantly accelerates wound closure. Using single-cell RNA sequencing of the wound, we show that following MSC delivery, innate immune cells, particularly macrophages, exhibit distinctive transcriptional changes. We identify the appearance of a pro-angiogenic CD9+ macrophage subpopulation, whose induction is mediated by several proteins secreted by MSCs, including COL6A1, PRG4, and TGFB3. Our findings suggest that MSCs do not need to act locally to induce broad changes in the immune system and ultimately treat disease.
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Macrófagos Alveolares/inmunología , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/inmunología , Transcripción Genética/genética , Cicatrización de Heridas/inmunología , Animales , Modelos Animales de Enfermedad , Femenino , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Infusiones Intravenosas/métodos , Macrófagos Alveolares/metabolismo , Ratones , Ratones Endogámicos BALB C , Células RAW 264.7 , RNA-Seq/métodos , Análisis de la Célula Individual/métodos , Tetraspanina 29/metabolismoRESUMEN
BACKGROUND: Reinforcement of the abdominal wall with synthetic mesh in autologous breast reconstruction using abdominal free tissue transfer decreases the risk of bulging and herniation. However, the impact of the plane of mesh placement on donor site complications has not yet been investigated. METHODS: We performed a retrospective analysis of 312 patients who had undergone autologous breast reconstruction with muscle-sparing transverse rectus abdominis myocutaneous (MS-TRAM) flaps or deep inferior epigastric perforator (DIEP) flaps as well as polypropylene mesh implantation at the donor site. Donor site complications were compared among patients with different flap types and different mesh positions including overlay (n = 90), inlay and overlay (I-O; n = 134), and sublay (n = 88). RESULTS: Abdominal hernias occurred in 2.86% of patients who had undergone MS-TRAM reconstructions and in 2.63% of patients who had undergone DIEP reconstructions. When comparing patients with different mesh positions, donor site complications occurred in 14.4% of patients with overlay mesh, 13.4% of patients with I-O mesh, and 10.2% of patients with sublay mesh (P = 0.68). Abdominal hernias occurred in 4.44% of patients with overlay mesh, 2.24% of patients with I-O mesh, and 2.27% of patients with sublay mesh (P = 0.69). Multivariable logistic regression analysis did not identify a significant association between mesh position and hernia rates as well as wound complications. CONCLUSIONS: Our data indicate that the plane of synthetic mesh placement in relation to the rectus abdominis muscle does not impact the rate of postoperative donor site complications in patients undergoing breast reconstruction with MS-TRAM or DIEP flaps.
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Pared Abdominal , Mamoplastia , Colgajo Perforante , Arterias Epigástricas/cirugía , Humanos , Mamoplastia/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Recto del Abdomen/trasplante , Estudios Retrospectivos , Mallas Quirúrgicas/efectos adversosRESUMEN
GENERAL PURPOSE: To review the various mechanical forces that affect fibroblasts, keratinocytes, endothelial cells, and adipocytes at the cellular and molecular level as well as scar-reducing mechanical devices currently in clinical use. TARGET AUDIENCE: This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care. LEARNING OBJECTIVES/OUTCOMES: After participating in this educational activity, the participant will:1. Compare and contrast the responses of various types of cells to mechanical forces.2. Identify the mechanical devices and techniques that can help restore skin integrity.
Skin provides a critical protective barrier for humans that is often lost following burns, trauma, or resection. Traditionally, skin loss is treated with transfer of tissue from other areas of the body such as a skin graft or flap. Mechanical forces can provide powerful alternatives and adjuncts for skin replacement and scar modulation. This article first provides an overview of the various mechanical forces that affect fibroblasts, keratinocytes, endothelial cells, and adipocytes at the cellular and molecular level. This is followed by a review of the mechanical devices currently in clinical use that can substantially augment the restoration of skin integrity and reduce scarring. Methods described include tissue expanders, external volume expansion, negative-pressure wound therapy, and skin taping.
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Adipocitos/fisiología , Células Endoteliales/fisiología , Fibroblastos/fisiología , Queratinocitos/fisiología , Mecanotransducción Celular/fisiología , Cicatrización de Heridas/fisiología , Humanos , Técnicas de Cierre de HeridasRESUMEN
BACKGROUND: Pressure injury is seen across all healthcare settings and affects people of any age and health condition. It imposes a significant burden, with annual costs of up to $17.8 billion in the United States alone. Despite considerable resources it exhausts, the disease remains very prevalent, and the incidence is on the rise. This is in part due to aging population, growing number of nursing home residents, poorly understood biology, and dismal track record of clinical research in this field. METHODS: In our Review Article, we discuss the disease pathophysiology, clinical manifestation, evidence based recommendations for risk assessment, prevention and timely management, existing challenges, and directions to improve research on the field. This article encompasses dedicated sections on the full spectrum of the pressure related pathologies including "conventional pressure ulcers", "medical device related pressure injuries", "pressure injuries in mucosal membranes", "pressure injuries in pediatric population", "pressure injury at end of life", and the "role of pressure in pathogenesis of diabetic foot ulcers".
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Úlcera por Presión/epidemiología , Úlcera por Presión/prevención & control , Humanos , Incidencia , Úlcera por Presión/economía , Úlcera por Presión/fisiopatología , Prevalencia , Medición de Riesgo , Factores de Riesgo , Estados Unidos/epidemiologíaRESUMEN
Although bone marrow-derived mesenchymal stem cells (BM-MSCs) are widely recognized as promising therapeutic agents, the age-related impacts on cellular function remain largely uncharacterized. In this study, we found that BM-MSCs from young donors healed wounds in a xenograft model faster compared with their aged counterparts (p < .001). Given this significant healing advantage, we then used single-cell transcriptomic analysis to provide potential molecular insights into these observations. We found that the young cells contained a higher proportion of cells characterized by a higher expression of genes involved in tissue regeneration. In addition, we identified a unique, quiescent subpopulation that was exclusively present in young donor cells. Together, these findings may explain a novel mechanism for the enhanced healing capacity of young stem cells and may have implications for autologous cell therapy in the extremes of age. Stem Cells 2019;37:240-246.
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Células Madre Mesenquimatosas/metabolismo , Transcriptoma/genética , Adulto , Anciano , Envejecimiento , Animales , Diferenciación Celular , Proliferación Celular , Senescencia Celular , Humanos , Ratones , Adulto JovenRESUMEN
This retrospective, matched-cohort study analyzed 1,556 patients with diabetic ulcers treated at 470 wound centers throughout the United States to determine the effectiveness of a cryopreserved bioactive split-thickness skin allograft plus standard of care when compared to standard of care alone. There were 778 patients treated with the graft in the treatment cohort, who were paired with 778 patients drawn from a pool of 126,864 candidates treated with standard of care alone (controls), by using propensity matching to create nearly identical cohorts. Both cohorts received standard wound care, including surgical debridement, moist wound care, and offloading. Logistic regression analysis of healing rates according to wound size, wound location, wound duration, volume reduction, exposed deep structures, and Wagner grade was performed. Amputation rates and recidivism at 3 months, 6 months, and 1 year after wound closure were analyzed. Diabetic ulcers were 59% more likely to close in the treatment cohort compared to the control cohort (p = 0.0045). The healing rate with the graft was better than standard of care across multiple subsets, but the most significant improvement was noted in the worst wounds that had a duration of 90-179 days prior to treatment (p = 0.0073), exposed deep structures (p = 0.036), and/or Wagner Grade 4 ulcers (p = 0.04). Furthermore, the decrease in recidivism was statistically significant at 3 months, 6 months, and 1 year, with and without initially exposed deep structures (p < 0.05). The amputation rate in the treatment cohort was 41.7% less than that of the control cohort at 20 weeks (0.9% vs. 1.5%, respectively). This study demonstrated that diabetic ulcers treated with a cryopreserved bioactive split-thickness skin allograft were more likely to heal and remain closed compared to ulcers treated with standard of care alone.
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Pie Diabético/cirugía , Trasplante de Piel/métodos , Trasplante Homólogo/métodos , Anciano , Vendajes , Estudios de Cohortes , Criopreservación , Desbridamiento , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Nivel de Atención , Resultado del Tratamiento , Cicatrización de HeridasRESUMEN
Chronic wounds affect roughly 6.5 million patients in the US annually. Current standard of therapy entails weekly sharp debridement. However, the sharp technique is associated with significant pain, while having minimal impact on the bioburden. Our study proposes the Er:YAG laser as an alternative method of debridement that may decrease procedural pain, reduce bioburden, and potentially improve overall healing. This pilot study was performed as a prospective, randomized, controlled, crossover clinical trial, containing two groups: (1) one group underwent single laser debridement session first, followed by single sharp debridement session one week later; and (2) the other group underwent single sharp debridement session first, followed by single laser debridement session one week later. Variables analyzed included pain during debridement, pre- and post-debridement wound sizes, pre- and post-debridement bacterial loads and patient preference. Twenty-two patients were enrolled (12 patients in Group 1, plus 10 patients in Group 2). The mean pain score for patients undergoing laser debridement was 3.0 ± 1.7 vs. 4.8 ± 2.6 for those undergoing sharp debridement (p = 0.003). The mean percent change in wound size 1-week post-laser debridement was -20.8% ± 80.1%, as compared with -36.7% ± 54.3% 1-week post-sharp debridement (p = 0.6). The percentage of patients who had a bacterial load in the low/negative category increased from 27.3% to 59.1% immediately after laser debridement (p = 0.04), vs. 54.5% to 68.2% immediately after sharp debridement (p = 0.38). Moreover, there was a sustained decrease in bacterial load 1-week post-laser debridement, as compared with no sustained decrease 1-week post-sharp debridement (p < 0.02). Overall, 52.9% of patients preferred laser debridement vs. 35.3% for sharp debridement. We believe that Er:YAG laser serves as a promising technology in chronic wounds, functioning as a potentially superior alternative to sharp debridement, the current standard of therapy.