The mechanisms underlying the complex and multistage wound-healing process are not yet completely understood. One of the most important and intriguing questions remaining is the effect of the interactions between wounds and the microflora that are present in wounds. In this report, we describe the first study of the effect of treating murine skin wounds with topical bacterial lipopolysaccharide (LPS), the main exogenous ligand of Toll-like receptor 4. Our findings demonstrate that LPS treatment strongly affects the wound-healing process by accelerating the resolution of inflammation, increasing macrophage infiltration, enhancing collagen synthesis, and altering the secretion of a number of mediators that are involved in the skin regeneration process. Topical LPS treatment upregulated the secretion of proinflammatory cytokines [interleukin (IL)-6, IL-1β, and leukemia inhibitory factor (LIF)] and CC-chemokines (CCL2/MCP-1, CCL7/MCP-3, CCL3/MIP-1α, and CCL5/RANTES), but not CXC-chemokines (CXCL2/MIP-2 and CXCL9/MIG). The secretion of growth factors (vascular endothelial growth factor, transforming growth factor-β1 (TGF-β1), and fibroblast growth factor 2) at the wound site was also upregulated. Taken together, these results suggest that the topical application of LPS at the wound surface affects the inflammatory process and promotes the wound healing of injured skin.

Psoriasis and seborrheic dermatitis are common papulosquamous dermatoses. When localized only on the scalp, they often have very similar clinical manifestations and require a comprehensive differential diagnostic approach. The article presents the main comparative clinical and diagnostic characteristics of psoriasis and seborrheic dermatitis of the scalp, including trichoscopy features and pathomorphological markers. Topical therapy with glucocorticosteroids, keratolytics and agents with antifungal activity is of key importance in the treatment of papulosquamous diseases. Modern topical drugs with a fixed combination of active ingredients provide an effect on several pathogenetic mechanisms at once, are stable, compatible, and convenient for use by patients. One of the main drugs for the treatment of psoriasis and seborrheic dermatitis is a solution of betamethasone dipropionate and salicylic acid (trade name – Akriderm SK), which in terms of anti-inflammatory activity is comparable to the highest strength topical corticosteroids, while providing a faster response to therapy and effectively relieving symptoms of itching and peeling. This is confirmed by the authors’ own clinical experience and demonstrated in the clinical cases described in the article.

BACKGROUND: Melanoma is a malignant neoplasm that arises from melanocytes, which are melanin-producing cells primarily found in the skin. Although rare, melanoma is highly aggressive. In 2023, 13,270 cases of skin melanoma were identified in Russia. The primary risk factor is excessive exposure to ultraviolet radiation. Immunohistochemical studies using markers such as HMB-45 (Human Melanoma Black-45), Melan-A/MART-1 (Melanoma Antigen Recognized by T Cells 1), and S100 are crucial for diagnosing skin melanoma, improving the accuracy of tumor detection, and optimizing treatment. AIM: This study aimed to assess the prognostic significance of melanocytic markers HMB-45, Melan-A/MART-1, and S100 in skin melanoma, taking into account tumor histological subtypes and stages according to the pTNM classification. METHODS: Skin melanoma samples from patients (n = 117) were assessed using immunohistochemistry with antibodies to HMB-45, Melan-A/MART-1, and S100. The results were interpreted based on the histological subtype of the tumor and the Breslow thickness, which was used to determine the disease stage. RESULTS: The count of atypical melanoma cells, considering the histological subtype of the tumor, showed that the S100 marker had the highest sensitivity (91.2%) compared to Melan-A/MART-1 and HMB-45, especially in desmoplastic melanoma. Moreover, S100 and Melan-A/MART-1 demonstrated stable staining regardless of the degree of invasion, whereas the number of HMB-45-positive atypical melanocytes increased as the tumor progressed according to the pTNM classification. CONCLUSION: Immunohistochemical analysis of various histological subtypes of skin melanoma revealed stable expression of S100, Melan-A/MART-1, and HMB-45 proteins in superficial spreading and nodular tumors. In desmoplastic melanoma, the expression of Melan-A/MART-1 and HMB-45 was absent, whereas S100 expression remained. The proportion of S100- and Melan-A/MART-1-positive atypical cells was independent of the degree of tumor invasion (according to pTNM stages). The percentage of HMB-45-positive atypical melanocytes increased proportionally with the thickness of invasion, supporting its prognostic significance.