Tissue expansion is a procedure that promotes skin regeneration by mechanical stretch. During the stress and relaxation cycle, the skin undergoes a repeated microtrauma which triggers an immune response leading to the recruitment of macrophages to repair the damaged tissue. Macrophages have been found to be necessary for tissue repair and wound healing, but their effects on skin regeneration during mechanical stretch remain unclear. The dynamic changes of macrophages in the rat skin tissues undergoing expansion were quantitatively determined by immunohistochemistry staining. The area of the expanded skin, skin thickness, dermal collagen density, cell proliferation and tissue vascularization were examined to determine the effects of macrophages on the expanding skin. The phenotypes of macrophages and the growth factors related to skin regeneration were also examined to evaluate the underlying mechanisms for the involvement of macrophages in skin regeneration. As a comparison, the tissue samples of expanding skin in which the macrophages were depleted by topically utilizing clodronate liposomes were also evaluated. The number of skin macrophages in skin maintained in the high level during the skin expansion compared to non-expanded skin. We found that a switch from an M1- to M2-dominant response during tissue expansion. After the macrophages were depleted, the skin regeneration was inhibited, as evidenced by a smaller expansion area, thinner skin layers and decreased cell proliferation rate, collagen synthesis and, skin vascularization. The secretion of epidermal growth factor (EGF), fibroblast growth factor (FGF), and vascular endothelial growth factor (VEGF) were decreased when macrophages were depleted. Our findings suggest that macrophages are necessary for skin regeneration during tissue expansion. Modulating inflammation may provide a key therapeutic strategy to promote skin growth under mechanical strain.

Background: Tissue expansion, a technique in which skin regeneration is induced by mechanical stretch stimuli, is commonly used for tissue repair and reconstruction. In this study, we aimed to monitor the autophagy levels of expanded skin after the application of expansion stimuli and explore the effect of autophagy modulation on skin regeneration.Methods: A rat scalp expansion model was established to provide a stable expanded skin response to mechanical stretch. Autophagy levels at different time points (6, 12, 24, 48 and 72 h after the last expansion) were detected via western blotting. The effect of autophagy regulation on skin regeneration during tissue expansion was evaluated via skin expansion efficiency assessment, western blotting, immunofluorescence staining, TUNEL staining and laser Doppler blood flow imaging.Results: The autophagic flux reached its highest level 48 h after tissue expansion. Activating autophagy by rapamycin increased the area of expanded skin as well as the thicknesses of epidermis and dermis. Furthermore, activating autophagy accelerated skin regeneration during tissue expansion by enhancing the proliferation of cells and the number of epidermal basal and hair follicle stem cells, reducing apoptosis, improving angiogenesis, and promoting collagen synthesis and growth factor secretion. Conversely, the regenerative effects were reversed when autophagy was blocked.Conclusions: Autophagy modulation may be a promising therapeutic strategy for improving the efficiency of tissue expansion and preventing the incidence of the complication of skin necrosis.

Background: Early recognition of castration-resistant state is of significance for timely adjustment of treatment regimens and improvement of prognosis. Purpose: This study aims to screen new aptamers CRda8 and CRda21 which recognize castration resistant prostate cancer (CRPC) cells with high affinity and specificity by SELEX technology. Methods: The enrichment of specific aptamer candidates was monitored by flow cytometric analysis. The affinity and specificity of aptamer candidates were evaluated by flow cytometry and immunofluorescence assay. MR imaging of CRda21-conjugated polyethylene glycol (PEG)-Fe₃O₄ nanoparticles to CRPC was further explored in vivo. Results: Both aptamers showed high specificity to target cells with dissociation constants in the nanomolar range, and did not recognize other tested cells. The staining of clinical tissue sections with fluorescent dye labeled aptamers showed that sections from CRPC exhibited stronger fluorescence while sections from benign prostatic hyperplasia and androgen dependent prostate cancer did not exhibit notable fluorescence. In vivo MRI demonstrated that CRda21-conjugated PEG-Fe₃O₄ had good affinity to CRPC and produced strong T2WI signal intensity reduction distinguished from peritumoral tissue. Conclusion: The high affinity and specificity of CRda8 and CRda21 make the aptamer hold potential for early recognition of castration-resistant state and diagnosis of CRPC at the cellular level.

Background: Acute alcohol intoxication is linked to poor trauma outcomes, but its specific impact on emergency facial trauma surgery and the role of alcohol ingestion-surgery interval remain unclear. This study aimed to address these gaps. Methods: A retrospective study was conducted from December 2024 to July 2025, enrolling 84 patients requiring emergency surgery for facial trauma. Patients were divided into an observation group (n=42, intoxicated at admission) and a control group (n=42, nonintoxicated). Data on demographics, alcohol use, trauma details, surgical parameters [eg, Maxillofacial Injury Severity Score (MFISS), cooperation, duration, blood loss], and postoperative outcomes (early complications, wound healing, scar assessment at 6 mo) were collected. The observation group was further stratified by the interval from drinking to surgery (0–6, 6–12, and 12–24 h) for subgroup analysis. Results: Intoxicated patients had significantly higher MFISS scores, poorer intraoperative cooperation, longer operation times, and greater blood loss compared with controls (all P <0.05). The overall incidence of early complications (erythema and infection) was significantly higher in the observation group (23.81% versus 7.14%, P =0.034). Subgroup analysis revealed that patients undergoing surgery within 6 hours of alcohol ingestion had the highest complication rate (57.14%), significantly higher than the 6 to 12 hours subgroup (16.13%, P <0.05), with no complications in the 12 to 24 hours subgroup. No significant intergroup differences were found in final wound healing grade, suture removal time, or 6-month Vancouver Scar Scale scores. Conclusion: Acute alcohol intoxication adversely affects emergency facial trauma surgery, especially if surgery is within 6 hours of ingestion. For stable patients, delaying surgery to ≥6 hours post-ingestion and preoperative alcohol screening are recommended.