The efficient management of skin wounds for rapid and scarless healing represents a major clinical unmet need. Nonhealing skin wounds and undesired scar formation impair quality of life and result in high healthcare expenditure worldwide. The skin-colonizing microbiota contributes to maintaining an intact skin barrier in homeostasis, but it also participates in the pathogenesis of many skin disorders, including aberrant wound healing, in many respects. This review focuses on the composition of the skin microbiome in cutaneous wounds of different types (i.e. acute and chronic) and with different outcomes (i.e. nonhealing and hypertrophic scarring), mainly based on next-generation sequencing analyses; furthermore, we discuss the mechanistic insights into host–microbe and microbe–microbe interactions during wound healing. Finally, we highlight potential therapeutic strategies that target the skin microbiome to improve healing outcomes.

Human adipose-derived stem cells (hADSCs) are an important source of cells for regenerative medicine. Evidence of extensive interactions with the surrounding microenvironment has led researchers to focus more on hADSCs as activating agents of regenerative pathways, rather than simply replacing damaged cells. Several studies have found that functional miRNAs can be packaged into exosomes and transferred from donor cells into recipient cells, indicating that transported miRNAs may be a new class of cell-to-cell regulatory species. The aim of the present study was to evaluate whether the exosome-derived miRNAs secreted by hADSCs are capable of influencing angiogenesis, a key step in tissue regeneration. Exosomes were purified from hADSCs followed by the characterization of their phenotype and angiogenic potential in vitro. RNA sequencing was performed to detect the miRNAs that were enriched in the hADSC-derived exosomes. A miRNA-mimic experiment was used to detect the key miRNAs in the proangiogenic activity of hADSC-derived exosomes. Exosomes isolated from hADSCs were characterized as round membrane vesicles with a size of approximately 100 nm and were positive for CD9 and flotillin. The exosomes were internalized by primary human umbilical vein endothelial cells (HUVECs) and stimulated HUVEC proliferation and migration. Remarkably, the exosomes promoted vessel-like formation by HUVECs in a dose-dependent manner, and their maximum activity (10 μg/mL) was comparable with that of 5% FBS. The RNA-seq bioinformatics analysis predicted 1119 gene targets of the top 30 exosomal miRNAs in Gene Ontology (GO) analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis, and the pathway involved in the angiogenesis was among the top KEGG pathways. Moreover, intact miR-423-5p was further demonstrated to be transferred into HUVECs via exosomes and to exert its angiogenic function by targeting Sufu. Exosomal miR-423-5p mediated the proangiogenic activity of hADSCs by targeting Sufu, which may contribute to the exploitation of exosomes from hADSCs as a therapeutic tool for regenerative medicine.

Continuous sutures and interrupted sutures have been widely applied to skin closure after non‐obstetric surgery or traumatic wounds. Usually, continuous sutures were divided into transdermal or subcuticular sutures according to whether the stitches were placed through or below the epidermal layer. Interrupted sutures, on the other hand, involved penetration of the loose connective tissue beneath the skin layers, with stitches placed through the external skin layer. Complications including infection, dehiscence, and poor cosmetic appearance were not rare after suturing. Whether a suture method is a suitable option for rapid wound healing and long‐term cosmetic appearance remains controversial. To examine the potential benefits and harms of continuous skin sutures vs interrupted skin sutures in non‐obstetric surgery or traumatic wounds. Searching websites such as PubMed, the Cochrane Central Library, Web of Science and Embase, and ClinicalTrials.gov were systematically searched up to 5 January 2022 and were assessed and guided by Preferred Reporting Items for Systematic Reviews and Meta‐analysis rules as well as guidelines. All relevant randomised controlled studies comparing continuous sutures with interrupted sutures of skin closure were analysed. The suture techniques and material used in each trial were recorded. The transdermal and subcuticular continuous sutures were separately compared with interrupted sutures in the subgroup analysis of dehiscence and cosmetic appearance because the visual appearance of these two continuous suturing techniques was significantly different. Ten studies including 1181 participants were analysed. Subcuticular continuous sutures had comparatively higher visual analogue scale (VAS) scores among patients and doctors than interrupted sutures (OR = 0.27, 95% Confidence Intervals [CI] = 0. 07‐0.47, P < .01). Similarly, priority was found regarding transdermal continuous sutures and interrupted sutures (OR = 0.40, 95% CI = 0.21‐0.60, P < .01). Five randomised controlled trials (RCTs) demonstrated relevant data about dehiscence events. The incidence of continuous suture was significantly lesser than that of interrupted suture (OR = 0.16, 95% CI = 0.07‐0.37, P < .01). There was no significant difference between the infection events rates of two suture methods (OR = 0.69, 95% CI = 0.40‐1.21, P = .62, I² = 0%). This systematic review indicated the superiority of both transdermal and subcutaneous continuous sutures over interrupted sutures in skin closure in terms of wound healing and cosmetic appearance.

Background: The indications for sentinel lymph node biopsy (SLNB) for thin melanoma are still unclear. This meta-analysis aims to determine the positive rate of SLNB in thin melanoma and to summarize the predictive value of different high-risk features for positive results of SLNB.Methods: Four databases were searched for literature on SLNB performed in patients with thin melanoma published between January 2000 and December 2020. The overall positive rate and positive rate of each high-risk feature were calculated and obtained with 95% confidence intervals (CIs). Both unadjusted odds ratios (ORs) and adjusted ORs (AORs) of high-risk features were analyzed. Pooled effects were estimated using random-effects model meta-analyses.Results: Sixty-six studies reporting 38,844 patients with thin melanoma who underwent SLNB met the inclusion criteria. The pooled positive rate of SLNB was 5.1% [95% confidence interval (CI) 4.9%-5.3%]. Features significantly predicted a positive result of SLNB were thickness≥0.8 mm [AOR 1.94 (95%CI 1.28-2.95); positive rate 7.0% (95%CI 6.0-8.0%)]; ulceration [AOR 3.09 (95%CI 1.75-5.44); positive rate 4.2% (95%CI 1.8-7.2%)]; mitosis rate >0/mm2 [AOR 1.63 (95%CI 1.13-2.36); positive rate 7.7% (95%CI 6.3-9.1%)]; microsatellites [OR 3.8 (95%CI 1.38-10.47); positive rate 16.6% (95%CI 2.4-36.6%)]; and vertical growth phase [OR 2.76 (95%CI 1.72-4.43); positive rate 8.1% (95%CI 6.3-10.1%)].Conclusions: The overall positive rate of SLNB in thin melanoma was 5.1%. The strongest predictor for SLN positivity identified was microsatellites on unadjusted analysis and ulceration on adjusted analysis. Breslow thickness ≥0.8 mm and mitosis rate >0/mm² both predict SLN positivity in adjusted analysis and increase the positive rate to 7.0% and 7.7%. We suggest patients with thin melanoma with the above high-risk features should be considered for giving an SLNB.