scholarly journals An Electrospun Poly-Ethylene Oxide/Cerium (III) Nitrate Dressing for Delayed Debridement and Improved Wound Healing of Warfighter Contact Burns

Author(s):  
Thompson MA ◽  
Kowalczewski C ◽  
Roy J ◽  
Nathan Wienandt MAJ ◽  
Williams C III ◽  
...  

Introduction: Thermal burns account for 5-10% of casualties sustained in present-day conflicts and are expected to be one of the most common wounds to occur in future conflicts. Timely debridement of necrotic burn tissue can greatly reduce the chances of mortality and late-stage complications. However, future conflicts are anticipated to occur in austere environments where surgical debridement may not be plausible and casualty evacuations significantly delayed. Without access to prompt surgical interventions and standard treatment, burn wounds can progress (become deeper and more extensive) and become highly susceptible to infection. Several studies have demonstrated that topical applications of Cerium (III) Nitrate (Cen) can be used to delay the need for surgical eschar removal, a delay which may be forced upon injured warfighters in austere environments. The proof-of-concept studies described herein suggest that an electrospun dressing with a Polyethylene Oxide (PEO) shell and CeN core could prolong the time before surgical intervention is required and/or mitigate late-stage burn pathophysiologies in Prolonged Field Care (PFC) scenarios. Materials and Methods: Coaxially electrospun PEO dressings with a CeN payload were synthesized for application in a swine burn model. Dressings were first evaluated ex vivo using a Lactate Dehydrogenase (LDH) assay to confirm that no cytotoxic effects were present. Then, one female Yorkshire pig was anesthetized and received ten 5 cm x 5 cm contact burns with a brass burn device that was heated to 100°C. The deep-partial thickness wounds were randomly assigned to one of five treatment groups: 1) 1-Layer of the PEO/CeN dressing, 2) 4-Layers of the PEO/CeN dressing, 3) 4-layers of a control electrospun PEO dressing, 4) Flammacerium® cream (silver sulfadiazine 1%, cerium nitrate 2.2%), or 5) the PFC standard of care (SOC; gauze). Wounds were observed over an 18-day period, with surgical debridement occurring on Day 4 for all wounds. Transepidermal water loss, depth to debridement, and histologic measurements of necrosis were utilized to assess the burns. Research was conducted in compliance with the Animal Welfare Act, the implementing Animal Welfare regulations, and the principles of the Guide for the Care and Use of Laboratory Animals, National Research Council. The facility’s Institutional Animal Care and Use Committee approved all research conducted in this study. The facility where this research was conducted is fully accredited by AAALAC International. Experimental design and statistical comparisons were approved by an accredited epidemiologist and biostatistician. Results: The PEO/CeN dressings did not elicit a cytotoxic response ex vivo. Compared to the PFC SOC, treatments containing CeN reduced the amount of necrotic tissue produced by second-degree thermal injuries, as evidenced both histologically and in the depth required to reach viable tissue during surgical debridement. Importantly, the dressing did not adversely impact the live tissue surrounding the burn site. Conclusions: There are currently no field dressings that can delay the need for immediate debridement and thereby promote burn wound healing. This proof-of-concept study strongly suggests that the electrospun PEO/CeN dressing could fulfill this unmet medical need and advocates for further evaluation for use in imminent PFC scenarios.

2020 ◽  
Author(s):  
Aiping Liu ◽  
Edgar Ocotl ◽  
Aos Karim ◽  
Josiah J. Wolf ◽  
Benjamin L. Cox ◽  
...  

AbstractBackgroundEarly mechanisms underlying the progressive tissue death and the regenerative capability of burn wounds are understudied in human skin. A clinically relevant, reproducible model for human burn wound healing is needed to elucidate the early changes in the human burn wound environment. This study reports a reproducible contact burn model on human skin that explores the extent of tissue injury and healing over time, and defines the inter-individual variability in human skin to enable use in mechanistic studies on burn wound progression and healing.MethodsUsing a customized burn device, contact burns of various depths were created on human skin by two operators and were evaluated for histologic depth by three raters to determine reproducibility. Early burn wound progression and wound healing were also evaluated histologically after the thermally injured human skin was cultured ex vivo for up to 14 days.ResultsBurn depths were reproducibly generated on human skin in a temperature- or time-dependent manner. No significant difference in operator-created or rater-determined depth was observed within each patient sample. However, significant inter-individual variation was identified in burn depth in ten patient samples. Burn-injured ex vivo human skin placed into culture demonstrated differential progression of cell death and collagen denaturation for high and low temperature contact burns, while re-epithelialization was observed in superficial burn wounds over a period of 14 days.ConclusionThis model represents an invaluable tool to evaluate the inter-individual variability in early burn wound progression and wound healing to complement current animal models and enhance the translation of preclinical research to improvements in patient care.


Author(s):  
Sritharadol Rutthapol ◽  
Chunhachaichana Charisopon ◽  
Kumlungmak Sukanjana ◽  
Buatong Wilaiporn ◽  
Dechraksa Janwit ◽  
...  

ABSTRACT This study evaluated the effect of mupirocin topical spray on burn wound healing in a rat model. Fifteen male Sprague Dawley rats were used to create full-thickness burns on the rat dorsum using a cylindrical stainless steel rod. The rats were topically treated with normal saline solution (NSS), mupirocin spray, ointment, and solution. The wound size and morphological evaluation were investigated by photographs and clinical criterions for wound healing. The histology was observed by hematoxylin and eosin (HandE) staining assay. The immunohistochemical study was evaluated by detection of transforming growth factor-beta 1 (TGF-β1), and the ratio of matrix metalloproteinase-9 to the tissue inhibitor of matrix metalloproteinase-1 (MMP-9/TIMP-1) was quantified using the enzyme-linked immunosorbent assay (ELISA) assay. A complete healing was observed at 28 days in all treatments. Mupirocin formulations accelerated the wound healing faster than NSS in size. However, the clinical criteria indicated a desirable skin appearance in the mupirocin spray and ointment treated groups. The histological evaluations showed no differences between the treatments while the immunohistochemical study revealed that all treatments reduced the level of TGF-β1 over time, particularly on day 28 in the mupirocin spray and ointment treated groups. The MMP-9/TIMP-1 ratio was significantly lower in the mupirocin spray and ointment treated groups than in the NSS and mupirocin solution groups. This study shows the safety and efficacy in the use of mupirocin topical spray. The topical mupirocin spray is an alternative suitable for development as a human topical anti-infective and wound protection spray.


Author(s):  
Hana M. Hammad ◽  
Amer Imraish ◽  
Maysa Al-Hussaini ◽  
Malek Zihlif ◽  
Amani A. Harb ◽  
...  

Objective: Achillea fragrantissima L. (Asteraceae) is a traditionally used medicinal herb in the rural communities of Jordan. Methods: The present study evaluated the efficacy of the ethanol extract of this species on angiogenesis in both, ex vivo using rat aortic ring assay and in vivo using rat excision wound model. Results: In concentrations of 50 and 100 µg/ml, the ethanol extract showed angiogenic stimulatory effect and significantly increased length of capillary protrusions around aorta rings of about 60% in comparison to those of untreated aorta rings. In MCF-7 cells, the ethanol extract of A. fragrantissima stimulates the production of VEGF in a dose-dependent manner. 1% and 5% of ethanol extract of A. fragrantissima containing vaseline based ointment was applied on rat excision wounds for six days and was found to be effective in wound healing and maturation of the scar. Both preparations resulted in better wound healing when compared to the untreated control group and vaseline-treated group. This effect was comparable to that induced by MEBO, the positive control. Conclusion: The results indicate that A. fragrantissima has a pro-angiogenic effect, which may act through the VEGF signaling pathway.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Gertraud Eylert ◽  
Reinhard Dolp ◽  
Alexandra Parousis ◽  
Richard Cheng ◽  
Christopher Auger ◽  
...  

Abstract Background Multipotent mesenchymal stromal/stem cell (MSC) therapy is under investigation in promising (pre-)clinical trials for wound healing, which is crucial for survival; however, the optimal cell dosage remains unknown. The aim was to investigate the efficacy of different low-to-high MSC dosages incorporated in a biodegradable collagen-based dermal regeneration template (DRT) Integra®. Methods We conducted a porcine study (N = 8 Yorkshire pigs) and seeded between 200 and 2,000,000 cells/cm2 of umbilical cord mesenchymal stromal/stem cells on the DRT and grafted it onto full-thickness burn excised wounds. On day 28, comparisons were made between the different low-to-high cell dose groups, the acellular control, a burn wound, and healthy skin. Result We found that the low dose range between 200 and 40,000 cells/cm2 regenerates the full-thickness burn excised wounds most efficaciously, followed by the middle dose range of 200,000–400,000 cells/cm2 and a high dose of 2,000,000 cells/cm2. The low dose of 40,000 cells/cm2 accelerated reepithelialization, reduced scarring, regenerated epidermal thickness superiorly, enhanced neovascularization, reduced fibrosis, and reduced type 1 and type 2 macrophages compared to other cell dosages and the acellular control. Conclusion This regenerative cell therapy study using MSCs shows efficacy toward a low dose, which changes the paradigm that more cells lead to better wound healing outcome.


Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 713
Author(s):  
Nina Melnikova ◽  
Alexander Knyazev ◽  
Viktor Nikolskiy ◽  
Peter Peretyagin ◽  
Kseniia Belyaeva ◽  
...  

A design of new nanocomposites of bacterial cellulose (BC) and betulin diphosphate (BDP) pre-impregnated into the surface of zinc oxide nanoparticles (ZnO NPs) for the production of wound dressings is proposed. The sizes of crystalline BC and ZnO NPs (5–25%) corresponded to 5–6 nm and 10–18 nm, respectively (powder X-ray diffractometry (PXRD), Fourier-infrared (FTIR), ultraviolet (UV), atomic absorption (AAS) and photoluminescence (PL) spectroscopies). The biological activity of the wound dressings “BC-ZnO NPs-BDP” was investigated in rats using a burn wound model. Morpho-histological studies have shown that more intensive healing was observed during treatment with hydrophilic nanocomposites than the oleophilic standard (ZnO NPs-BDP oleogel; p < 0.001). Treatment by both hydrophilic and lipophilic agents led to increases in antioxidant enzyme activity (superoxide dismutase (SOD), catalase) in erythrocytes and decreases in the malondialdehyde (MDA) concentration by 7, 10 and 21 days (p < 0.001). The microcirculation index was restored on the 3rd day after burn under treatment with BC-ZnO NPs-BDP wound dressings. The results of effective wound healing with BC-ZnO NPs-BDP nanocomposites can be explained by the synergistic effect of all nanocomposite components, which regulate oxygenation and microcirculation, reducing hypoxia and oxidative stress in a burn wound.


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