HE染色分析：皮肤损伤修复的时间进程

HE staining showed that at the four examination time points (D1 to D14), the cells in the normal control group were arranged neatly and tightly, with a complete and clear epidermal structure. The collagen fibers in the dermis were densely and intricately arranged, the cytoplasm was uniformly eosinophilic, and the structures of appendages such as hair follicles and sebaceous glands were intact. The subcutaneous fat layer and muscle layer were clearly visible, with adipocytes and muscle fibers arranged neatly and densely, uniform in size, and with normal nuclear morphology. In the model control group, the epidermis exhibited incomplete keratinization, necrosis of varying degrees, and loss of structure. Cells were disintegrated and fragmented, with thickening observed. The collagen fibers in the dermis also showed necrosis of varying degrees and loss of structure, with pale cytoplasmic staining and pyknotic or absent nuclei. Necrotic areas were accompanied by inflammatory cell infiltration, primarily lymphocytes and neutrophils. Fibrous tissue showed varying degrees of hyperplasia, and there was mild hemorrhage in some areas with a few red blood cells accumulating. The conditions were particularly severe on D1 and D3, while the inflammatory cell infiltration was somewhat reduced on D7 and D14. At the D1 and D3 time points, both the rMAP group and the collagen group exhibited incomplete keratinization of the epidermis, necrosis of the epidermal layer, and formation of new epidermis in some areas. The dermal layer showed extensive necrosis of collagen fibers accompanied by inflammatory cell infiltration, primarily lymphocytes and neutrophils. Compared to the model group, the rMAP group and the collagen group showed gradual improvement in the repair of the epidermis and dermis, as well as a reduction in inflammatory cell infiltration at the D3, D7, and D14 time points. See Figure 1.