Healing Effects of Iranian Dwarf Elder on Full-thickness Epidermal Thermal Injury in Wistar Rats

Background: Wound healing is a physiologic process that cells and tissues react when the skin is exposed to thermal injury. The inflammatory process has ‎essential effects on wound healing that includes coordination between immunological and biological responses. Chemical and herbal medicines are locally or systemically administrated to help wound healing. Herbal medicines have become more prevalent in recent years due to fewer side effects. Dwarf elder is used to treating inflammation and has been reported to possess antibacterial and antioxidant activities. This plant is also effective against burns, wounds, eczema, and infection. Objectives: In this study, we evaluated the topical application of dwarf elder on full-thickness epidermal thermal wounds in Wistar rats. Methods: Thirty adult male Wistar rats of about 300 g were used. The rats were randomly divided into three groups: Control group, vehicle group treated with an ointment base, and treatment group treated with elder ointment 10%. The animals were anesthetized and were created burn wounds with an area of 1 cm2 using the Meyer method. After 21 days, the wounds were photographed with a Canon camera. The wound area and healing degree were calculated. Slides were stained with H&E and examined by light microscopy and GraphPad Prism software. Data were analyzed by SPSS software using ANOVA and Tukey’s test. The significance level was considered at P < 0.05. Results: The wound area on the 21st day was significantly lower in the treatment group than in the control and vehicle groups. The epithelium thickness (μm) was significantly higher in the treatment group than in the control and vehicle groups. The blood vessels were significantly higher in the treatment group than in the other groups. Conclusions: The study showed that elder extract could be an effective remedy to repair and heal thermal injury and burn wounds.

The impact of initial surgical management on outcome in patients with severe burns: a 9-year retrospective analysis

Purpose To investigate the prognostic value of the factors related to the initial surgical management of burn wounds in severely burned patients. Methods A total of 189 severely burned adult patients who were admitted to our institute between January 2012 and December 2020 and met the inclusion criteria were recruited. Patients were divided into survival and nonsurvival groups. The patient data included sex, age, total burn surface area (TBSA), burn index (BI), inhalation injury, mechanical ventilation, initial surgical management of the burn wound (including post-injury time before surgery, surgical duration, surgical area, intraoperative fluid replenishment, intraoperative blood loss, and intraoperative urine output), and duration in the burn intensive care unit (BICU). Independent samples t tests, Mann-Whitney U tests, and χ 2 tests were performed on these data. those of which with statistically significant differences were subjected to univariate and multivariate Cox regression analyses to identify independent risk factors affecting the prognosis of severely burned patients. Receiver operating characteristic (ROC) curves were plotted, and the area under the curve (AUC), optimal cut-off value were calculated. Patients were divided into two groups, according to the optimal cut-off value of the independent risk factors. The TBSA, surgical area and survival rates of the two groups during hospitalization were analysed. Results The survival group (146 patients) and the nonsurvival group (43 patients) differed significantly in TBSA, burn index, inhalation injury, mechanical ventilation, initial surgical area, intraoperative fluid replenishment, intraoperative blood loss, and duration in the BICU (P&lt;0.05). Univariate Cox regression analysis showed that TBSA, burn index, mechanical ventilation, initial surgical area, intraoperative fluid replenishment, and intraoperative blood loss were risk factors for death in severely burned patients (P&lt;0.05). Multivariate Cox regression analysis showed that the burn index and intraoperative blood loss were independent risk factors for death in severely burned patients (P&lt;0.05). When the intraoperative blood loss during the initial surgical management of burn wounds was used to predict death in 189 severely burned patients, the AUC was 0.637 (95% confidence interval (CI): 0.545-0.730, P=0.006), and the optimal cut-off for intraoperative blood loss was 750 ml. Kaplan-Meier survival analysis showed that the prognosis of the group with intraoperative blood loss ≤750 ml was better than that of the group with intraoperative blood loss &gt;750 ml (P=0.008). Meanwhile, the TBSA and surgical area in the group with intraoperative blood loss ≤750 ml were significantly lower than that of the group with intraoperative blood loss &gt;750 ml (P&lt;0.05). Conclusion The burn index and intraoperative blood loss during the initial surgical management of burn wounds are independent risk factors affecting the outcome of severely burned patients with good predictive values. During surgery, haemostatic and anaesthetic strategies should be adopted to reduce bleeding, and the bleeding volume should be controlled within 750 ml to improve the outcome.

Preparation of Silver Ion Antimicrobial Dressings and Prevention and Treatment of Central Venous Catheter-Related Infection on Burn Wounds of Critically Burned Patients

To further understand the characteristics of Ag+ antimicrobial dressings and its application value in the prevention and treatment of infections in burn patients, in the study, the Ag+ gel dressings were prepared and their physical and chemical characteristics were analyzed, and relationship between the gel dressing and central venous catheter (CVC)-related infections was further explored. The results showed that silver nitrate was made into nano silver particles, and its structure was clearly visible under microscope, and nano silver was further applied to preparation of Ag+ antibacterial dressings. Fibrocytes were clearly visible in Ag+ gel dressing and arranged uniformly, which indicated that Ag+ gel dressing had good compatibility with biological materials and had no obvious toxicity. Further clinical trials showed that Ag+ gel dressing can effectively reduce CVC-related infections. From 1 to 4 weeks of the experiment, the bacterial infection rate in burn wounds and blood of the treatment group (TG), which applied Ag+ gel dressing, was lower than the control group (P < 0.05). During the treatment, the burn healing rate of the TG was also greatly higher than the control group (P < 0.05). In addition, the burn wound exudate in the TG was greatly less than the control group (P < 0.05). In summary, the Ag+ gel dressing prepared has good biological and physical and chemical properties, which have bright prospects in the prevention and treatment of burn wounds and CVC-related infections. This study provides an experimental basis for clinical application of Ag+ gel dressing.

Fabrication, characterization and evaluation of the efficacy of gelatin/hyaluronic acid microporous scaffolds suffused with aloe-vera in a rat burn model

Burn induced injuries are commonly encountered in civilian and military settings, leading to severe morbidity and mortality. Objective of this study was to construct microporous bioactive scaffolds of gelatin-hyaluronic acid suffused with aloe-vera gel (Gela/HA/AvG), and to evaluate their efficacy in healing partial-thickness burn wounds. Scaffolds were characterized using Fourier transform-infrared spectroscopy, Scanning electron microscopy, and Thermo-gravimetric analysis to understand intermolecular interactions and morphological characteristics. In-vitro fluid uptake ability and hemolytic index of test scaffolds were also determined. In-vitro collagenase digestion was done to assess biodegradability of scaffolds. Wound retraction studies were carried out in Sprague Dawley rats inflicted with partial-thickness burn wounds to assess and compare efficacy of optimized scaffolds with respect to negative and positive control groups. In-vivo gamma scintigraphy using Technetium-99m labeled Immunoglobulin-G ( 99m Tc-IgG) as imaging agent was also performed to validate efficacy results. Histological and immunohistochemical comparison between groups was also made. Scaffolds exhibited mircoporous structure, with pore size getting reduced from 41.3 ± 4.3 µm to 30.49 ± 5.7 µm when gelatin conc. was varied from 1% to 5%. Optimized test scaffolds showed sustained in-vitro swelling behavior, were biodegradable and showed hemolytic index in range of 2.4–4.3%. Wound retraction study along with in-vivo gamma scintigraphy indicated that Gela/HA/AvG scaffolds were not only able to reduce local inflammation faster but also accelerated dermis regeneration. Immunohistochemical analysis, in terms of expression levels of epidermal growth factor and fibroblast growth factor-2 also corroborated in-vivo efficacy findings. Gela/HA/AvG scaffolds, therefore, can potentially be developed into an effective dermal regeneration template for partial-thickness burn wounds.

Functional Hydrogel Dressings for Treatment of Burn Wounds

The therapy of burns is a challenging clinical issue. Burns are long-term injuries, and numerous patients suffer from chronic pain. Burn treatment includes management, infection control, wound debridement and escharotomy, dressing coverage, skin transplantation, and the use of skin substitutes. The future of advanced care of burn wounds lies in the development of “active dressings”. Hydrogel dressings have been employed universally to accelerate wound healing based on their unique properties to overcome the limitations of existing treatment methods. This review briefly introduces the advantages of hydrogel dressings and discusses the development of new hydrogel dressings for wound healing along with skin regeneration. Further, the treatment strategies for burns, ranging from external to clinical, are reviewed, and the functional classifications of hydrogel dressings along with their clinical value for burns are discussed.

Healing effects of Solanum nigrum fruit extract on second-degree burn wounds and its antibacterial activity against common pathogens of burn infection

Aims: Solanum nigrum (S. nigrum) is a species of flowering plant from the Solanaceae family and one of the indigenous plants of Eurasia. Given the biological activities of this plant, like antimicrobial, antioxidant, and anti-inflammatory ones, this study assessed its effects on the healing process of second-degree burn wounds in rats. We also evaluated its antibacterial activity against common pathogens of burn wound infection (i.e., Pseudomonas aeruginosa, Staphylococcus aureus, and Acinetobacter baumanni). Methods: S. nigrum fruit extract was prepared by percolation and reflux methods. The extract was applied for the treatment of animal models with second-degree burn wounds. Parameters of wound healing and maturation, including collagen deposition, epithelialization, reduction of neutrophil migration, and angiogenesis, were evaluated. The antimicrobial activity of S. nigrum fruit extract against common pathogens of burn wound infection was assessed by the agar well diffusion method via measurement of zones of microbial growth inhibition. Results: Histological analysis showed a significant reduction in neutrophil migration by the 20% hydroalcoholic extract vs. control group (normal saline). In addition, we found that the 20% hydroalcoholic extract was more efficient than silver sulfadiazine in augmenting collagen deposition. S. nigrum hydro alcoholic extract also showed an inhibitory effect on S. aureus. Conclusion: S. nigrum 20% hydroalcoholic extract improved some of the wound healing parameters such as collagen deposition and inflammation. It also shows an inhibitory effect on S. aureus. So, it may have therapeutic effects on burns.

A Sequential Therapeutic Hydrogel With Injectability and Antibacterial Activity for Deep Burn Wounds’ Cleaning and Healing

As a severe clinical challenge, escharotomy and infection are always the core concerns of deep burn injuries. However, a usual dressing without multifunctionality leads to intractable treatment on deep burn wounds. Herein, we fabricated a sequential therapeutic hydrogel to solve this problem. Cross-linked by modified polyvinyl alcohol (PVA-SH/ε-PL) and benzaldehyde-terminated F127 triblock copolymers (PF127-CHO), the hydrogel demonstrated excellent mechanical properties, injectability, tissue adhesiveness, antibacterial activity, biocompatibility, and satisfactory wound cleaning through both in vitro and in vivo assays. Additionally, based on the conception of “sequential therapy,” we proposed for the first time to load bromelain and EGF into the same hydrogel in stages for wound cleaning and healing. This work provides a strategy to fabricate a promising wound dressing for the treatment of deep burn wounds with injectability and improved patients’ compliance as it simplified the process of treatment due to its “three in one” characteristic (antibacterial activity, wound cleaning, and healing effects); therefore, it has great potential in wound dressing development and clinical application.