ABSTRACT
SUMMARY: Laser photobiomodulation (laser PBM) is known to be able to accelerate burn wound healing in the animal model; however little evidence exists on the action of laser PBM on the expression of important proteins in wound healing in the animal model, such as VEGF and TGF-ß1. The aim of this study was to carry out a systematic review in order to analyse the effect of laser PBM on VEGF and TGF-ß expression during burn wound repair in the animal model. A systematic review was carried out of the EMBASE, PubMed/ MEDLINE and LILACS databases. The studies included were preclinical studies that analysed the action of laser PBM on the expression of VEGF and TGF-ß (1, 2, 3) during burn wound repair in the animal model. The SYRCLE risk of bias tool was used. Random effect models were used to estimate the combined effect. Increased VEGF expression was observed with the use of laser PBM at 4.93 J/cm2 per point in the first two weeks after induction of the burn wound, with greater size of effect in the second week (SDM = 5.72; 95% CI: 3.14 to 8.31, I2 = 0 %; very low certainty of evidence). We also observed that the effect of laser PBM on TGF-ß1 expression was greater than in the control in the first week (SDM = -0.45; 95% CI: -1.91 to 1.02, I2 = 51 %; very low certainty of evidence), but diminished in the third week after induction of the lesion (SDM = -2.50; 95% CI: 3.98 to -1.01, I2 = 0 %; very low certainty of evidence). Laser PBM has an effect on TGF-ß1 and VEGF expression, promoting burn wound repair in the animal model.
RESUMEN: Es sabido que la fotobiomodulación por láser (FBM láser) puede acelerar el proceso de curación de heridas por quemadura en modelo animal, sin embargo aún se carece de mayor evidencia sobre la acción de la FBM láser en la expresión de proteínas importantes en el proceso de curación de heridas en modelo animal, como VEGF y TGF-ß1. Así, el objetivo de este estudio fue realizar una revisión sistemática a fin de analizar el efecto de la FBM láser sobre la expresión de VEGF, TGF-ß durante el proceso de reparación de heridas por quemadura en modelo animal. Se realizó una búsqueda sistemática en las bases de datos EMBASE, PubMed/MEDLINE y LILACS. Se incluyeron estudios preclínicos que analizaron la acción de la FBM láser en la expresión de VEGF, TGF-ß (1, 2, 3) durante el proceso de reparación de heridas por quemadura en modelo animal. Se utilizó la herramienta de riesgo de sesgo SYRCLE. Se utilizaron modelos de efectos aleatorios para estimar el efecto combinado. Observamos aumento de la expresión de VEGF con el uso de FBM láser 4.93 J/cm2 por punto, en las dos primeras semanas tras inducción de la herida por quemadura, con mayor tamaño de efecto en la segunda semana (SDM = 5,72; IC del 95%: 3,14 a 8,31, I2 = 0 %; certeza de la evidencia muy baja). También se observó el efecto de la FBM láser en la expresión del TGF- ß1 que fue mayor que el control en la primera semana (SDM = - 0,45; IC del 95%: -1,91 a 1,02, I2 = 51 %; certeza de la evidencia muy baja), disminuyendo en la tercera semana tras inducción de la lesión (SDM = -2,50; IC del 95%: -3,98 a -1,01; I2 = 0 %; certeza de la evidencia baja). La TFB por láser ejerce influencia en la expresión de TGF-ß1 y VEGF favoreciendo el proceso de reparación de heridas por quemadura en modelo animal.
Subject(s)
Animals , Wound Healing/radiation effects , Transforming Growth Factor beta/drug effects , Low-Level Light Therapy , Vascular Endothelial Growth Factor A/drug effects , Burns/radiotherapy , Disease Models, AnimalABSTRACT
Summary Objective: To analyze morphological characteristics and organization of the collagen fibers of third degree burns from scalding compared to laser therapy and silver sulfadiazine, the latter considered as the gold standard. Method: Were selected 12 animals (Rattus norvegicus) also divided into three groups (control group [CG] - untreated burns; sulfadiazine group [SG] - burns were treated with silver sulfadiazine at 1%; laser group [LG] - burns were treated with photobiomodulation). The scald burns were carried out by using PVC mold, and the material collected on the 14th day after burn was prepared for morphological and optical retardation analysis for evaluation of inflammatory infiltrates and collagen organization, respectively. Results: On the 14th day, the laser and sulfadiazine groups had mild inflammatory response, while the control group showed an intense inflammatory process, with statistical significance between laser and control groups, but not between sulfadiazine and control groups. Laser and sulfadiazine groups no longer had granulation tissue, opposite to what was seen in the control group. The presence of hair follicles and ulcer did not significantly differ between groups. The optical retardation of collagen fibers was higher in sulfadiazine group, followed by laser and control groups. As for systemic effect, we were able to identify it by simply analyzing the presence or absence of granulation tissue. Conclusion: Morphologically, the laser or silver sulfadiazine treatments were similar and both provided better organization of collagen fibers in relation to the untreated group. However, the sulfadiazine group modulated the deposition of collagen fibers more efficiently than the laser group.
Resumo Objetivo: Analisar características morfológicas e organização das fibras colágenas de queimaduras de terceiro grau provocadas por escaldo em relação à terapia com laser e àquela considerada padrão-ouro, a sulfadiazina de prata. Método: Foram selecionados 12 animais (Rattus norvegicus), divididos igualmente em três grupos (grupo controle [GC] - queimaduras não tratadas; grupo sulfadiazina [GS] - queimaduras tratadas com sulfadiazina de prata 1%; grupo laser [GL] - queimaduras tratadas com fotobiomodulação). As queimaduras foram realizadas por escaldo com a utilização de molde de PVC, e o material coletado no 14º dia pós-queimadura foi preparado para análise morfológica e de retardo óptico, para avaliação do infiltrado inflamatório e da organização do colágeno, respectivamente. Resultados: No 14º dia, os grupos laser e sulfadiazina apresentaram resposta inflamatória leve, enquanto o grupo controle apresentou processo inflamatório intenso, havendo significância estatística entre os grupos laser e controle, mas não entre os grupos sulfadiazina e controle. Enquanto os grupos laser e sulfadiazina não apresentavam mais tecido de granulação, o grupo controle ainda apresentava. A presença de folículo piloso e de úlcera não diferiu significantemente entre os grupos. O retardo óptico das fibras colágenas foi maior no grupo sulfadiazina, seguido dos grupos laser e controle. Apenas a análise da presença ou ausência de tecido de granulação permitiu identificar o efeito sistêmico. Conclusão: Morfologicamente, os tratamentos com laser ou sulfadiazina de prata foram similares e ambos proporcionaram maior organização das fibras colágenas em relação ao grupo não tratado. Entretanto, o grupo sulfadiazina modulou a deposição das fibras colágenas mais eficientemente que o grupo laser.
Subject(s)
Animals , Female , Rats , Silver Sulfadiazine/administration & dosage , Burns/drug therapy , Burns/radiotherapy , Low-Level Light Therapy/methods , Time Factors , Wound Healing/physiology , Burns/pathology , Collagen/drug effects , Collagen/radiation effects , Disease Models, AnimalABSTRACT
PURPOSE: To characterize the effects of low-level laser (LLL) on third-degree burn wounds which were infected with Staphylococcus aureus (S. aureus) in diabetic rats. METHODS: Thirty streptozotocin-induced diabetic rats were divided into two groups: the control and the LLL groups. Third-degree burns were induced using a heated metal rod, and then, were contaminated with S. aureus. The wounds in the LLL group were irradiated with a LLL (685nm) daily for five consecutive days, starting three days after the induction. The wound area was measured at 3, 5, 8, 14 and 21 days after burning. At the end of trial, the skin samples were harvested. RESULTS: Reduction in wound areas in the LLL and control groups were significantly different only on the 21st day (p<0.05). The mean bacterial numbers in the LLL group were significantly lower (p<0.05) than those in the control group. The number of macrophages, new blood vessels, fibroblast, and elevated collagen deposition in the LLL group significantly increased compared to the control group (p<0.05). The mean breaking strength of scars in the control group was significantly lower (p<0.05) than that of the LLL group. CONCLUSION: The low-level laser improved the healing of S. aureus third-degree burn infections in diabetic rats.
Subject(s)
Animals , Male , Staphylococcal Infections/radiotherapy , Staphylococcus aureus , Burns/microbiology , Burns/radiotherapy , Low-Level Light Therapy/methods , Diabetes Mellitus, Experimental/physiopathology , Staphylococcus aureus/radiation effects , Time Factors , Burns/pathology , Random Allocation , Reproducibility of Results , Treatment Outcome , Rats, WistarABSTRACT
PURPOSE: To investigate the effectiveness of low-level laser therapy (LLLT) on gastrocnemius muscle morphology and Myod imunoexpression in a model of dorsal burn in rats. METHODS: Sixteen male Wistar rats were distributed into two groups: control group (CG): rats submitted to scald burn injury without treatment and laser treated group (LG): rats submitted to scald burn injury and treated with laser therapy. Fourteen days post-surgery, gastrocnemius muscle was evaluated being the specimens stained with HE and morphometric data was evaluated. MyoD expression was assessed by immunohistochemistry. RESULTS: The results showed that laser treated animals presented more organized tissue morphology compared to the non-treated animals, with a higher number of nucleus in the fibers. Also, the cross sectional area of the fibers and the MyoD immunoexpression in the laser treated groups was higher. CONCLUSION: Low-level laser therapy had positive effects on gastrocnemius muscle, improving tissue muscle morphology, increasing cross sectional area and MyoD immunoexpression. .
Subject(s)
Animals , Male , Burns/radiotherapy , Low-Level Light Therapy/methods , Muscle, Skeletal/radiation effects , MyoD Protein/analysis , Burns/metabolism , Burns/pathology , Cell Count , Disease Models, Animal , Immunohistochemistry , Muscle Fibers, Skeletal/radiation effects , Muscle, Skeletal/pathology , MyoD Protein/radiation effects , Rats, Wistar , Reproducibility of Results , Skin/injuries , Skin/radiation effects , Time Factors , Treatment OutcomeABSTRACT
Úlcera de Marjolin é uma transformação maligna em tecido cutâneo cronicamente inflamado ou traumatizado, que ocorre especialmente após queimaduras. O carcinoma de células escamosas é o tipo histológico mais encontrado nas úlceras de Marjolin, seguido de carcinoma basocelular e melanoma maligno. Sarcomas em úlcera de Marjolin são raros, correspondendo a aproximadamente 5% dessas degenerações malignas. Neste artigo é descrito o caso de paciente do sexo feminino, vítima de queimadura há 42 anos, com grande ulceração em dorso. A biópsia dessa ulceração evidenciou sarcoma pleomórfico de alto grau em úlcera de Marjolin. A paciente foi submetida a ressecção da ulceração e enxerto de pele no local, seguidos de radioterapia e quimioterapia adjuvantes. Em 3 anos de seguimento, a paciente não apresentou recidiva da neoplasia. Úlceras de Marjolin são neoplasias malignas de comportamento agressivo, com alto índice de metástases regionais. A importância de seu entendimento está na necessidade de prevenção das mesmas, com o tratamento adequado dos pacientes queimados, evitando-se a cicatrização por segunda intenção. Sarcomas em úlcera de Marjolin são considerados raros, com poucos casos relatados na literatura, o que demonstra a importância deste relato.
Marjolin's ulcer is a malignant transformation of traumatized or chronically inflamed cutaneous tissue that occurs after burns. The most common histological type of carcinoma found in Marjolin's ulcers is squamous cell carcinoma, followed by basal cell carcinoma and malignant melanoma. Sarcomas in Marjolin's ulcers are rare, representing approximately 5% of these malignant degenerations. In this report, we describe the case of a female patient who was burned 42 years prior, with a large ulceration on her back. Biopsy of the ulceration showed a high-grade pleomorphic sarcoma in the Marjolin's ulcer. The patient underwent resection of the ulceration and a skin graft followed by radiation therapy and adjuvant chemotherapy. In 3 years of follow-up, the patient had no tumor recurrence. Marjolin's ulcers are aggressive and have a high rate of regional metastases. It is important that clinicians develop an understanding of their prevention by properly treating burns. Sarcomas in Marjolin's ulcers are rare and few cases have been reported in the literature, which demonstrates the importance of this report.