ABSTRACT
BACKGROUND: Wound healing monitoring and timely decision-making are critical for wound classification. Tryptophan (Tr) intrinsic fluorescence, detected at 295/340 nm, provides a noninvasive approach for wound assessment. Our previous work demonstrated that this autofluorescence is associated with keratinocytes in a highly proliferative state in vitro. OBJECTIVE: We investigated the correlation between Tr fluorescence and key wound healing parameters, including re-epithelialization, fibrosis, neovascularization, and acute and chronic inflammation, using a rabbit model. METHODS: Seven rabbits underwent wound healing assessment over a 15-day period. We employed histological analysis from central and marginal biopsies, and UV fluorescence imaging captured by a monochromatic near-UV sensitive camera equipped with a passband optical filter (340 nm/12 nm). Excitation was achieved using a 295 nm LEDs ring lamp. Normalized fluorescence values were correlated with histological measurements using Pearson correlation. RESULTS: The UV fluorescence strongly exhibited a strong correlation with re-epithelization (r = 0.8) at the wound edge, with peak intensity observed between the sixth and ninth days. Notably, wound-healing dynamics differed between the wound center and edge, primarily attributed to variations in re-epithelialization, neovascularization, and chronic inflammation. CONCLUSION: Our findings highlight the presence of autofluorescence at 295/340 nm during wound healing, demonstrating a robust association with re-epithelialization. This excitation/emission signal holds promise as a valuable noninvasive strategy for monitoring wound closure, re-epithelialization, and other biological processes where Tr plays a pivotal role.
Subject(s)
Re-Epithelialization , Tryptophan , Wound Healing , Animals , Rabbits , Re-Epithelialization/physiology , Wound Healing/physiology , Disease Models, Animal , Fluorescence , Skin/pathology , Skin/injuries , Optical Imaging/methods , Inflammation/pathology , Ultraviolet RaysABSTRACT
El propósito del presente estudio fue evaluar el efecto carcinógeno del metronidazol para el adenocacinoma de colon en ratas. Un total de 100 ratas de la cepa Wistar fueron asignados aleatoriamente en dos grupos. El grupo experimental estuvo integrado por animales que recibieron metronidazol oralmente, 50 mg/kg/día por 10 días, repitiéndose el tratamiento cada 15 días en tres ocasiones. El grupo control recibió solución fisiológica oralmente. Después de 12 meses de observación se realizó colectomía total en busca de datos histológicos de adenocarinoma. Se determinó el nivel sérico de antígeno carcinoembrionario. En ninguno de los grupos estudiados se encontró evidencia de displasia o cáncer de colon. En el grupo experiemental, 8 por ciento de las ratas desarrollaron hiperplasia mamaria, mientras que en el grupo control fue de 0 por ciento. Las ratas tratadas con metronidazol tuvieron un nivel sérico más alto de antígeno carcinoembrionario en relación al grupo control, 10.6 ñ 1.6 ng/mL vs 1.4 ñ 1.6 ng/mL, respectivamente (p< 0.05). Estos resultados demuestran que el tratamiento con metronidazol no tiene efecto carcinógeno después de 12 meses de observación
