Daily Cosmetic Research Analysis

BACKGROUND: Skin sensitising preservatives are commonly used in consumer and industrial products. The widespread use of preservatives has led to recurrent epidemics of contact allergy. OBJECTIVES: To investigate temporal trends of contact allergy to preservatives from 2014 to 2023. MATERIALS AND METHODS: Patients consecutively patch tested with preservatives from the European baseline series and the supplementary baseline series at Gentofte hospital from 2014 to 2023 were included. RESULTS: The study population included 6435 patients. Contact allergy to benzisothiazolinone (BIT) increased significantly from ≤ 0.3% in 2014 to 5.0% in 2023. Painters and machine operators, and assemblers were most often sensitised to BIT, and detergents and paints were the most common exposures to BIT. Contact allergy to methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) decreased significantly from 3.3% in 2014 to 2.2% in 2023. Likewise, contact allergy to MI declined significantly from 3.9% in 2014 to 2.5% in 2023. Stable trends were found for the overall prevalence of contact allergy to preservatives from 9.0% in 2014 to 10.2% in 2023. CONCLUSIONS: Regulatory restrictions on the use of MI and MCI/MI in cosmetic products have led to a decrease in contact allergy. However, the rise in contact allergy to BIT underscores the need for ongoing monitoring and preventive measures.

OBJECTIVES: Microneedle radiofrequency (MRF) is a promising skin rejuvenation treatment. However, the mechanisms underlying its effects on extracellular matrix (ECM) remodeling remain unclear. This study aimed to investigate the immediate histological effects of MRF under varying settings, its short-term impact on collagen and elastin synthesis, and the roles of fibroblasts and adipose-derived stem cells (ADSCs). MATERIALS AND METHODS: Porcine abdominal skin was treated with an MRF device containing 49 insulated microneedles using varying energy parameters (8-12 W; 100-300 ms). Immediate histological responses to treatment were evaluated through hematoxylin and eosin (H&E) staining. Short-term changes in collagen and elastin synthesis at Days 7 and 28 posttreatment were assessed via picrosirius red and Victoria blue staining. Additionally, expression and distribution of ECM remodeling-related proteins (MMPs, TGF-β, EGF, Ki67) and ADSCs were analyzed by multiplex immunohistochemistry (mIHC) and western blot analysis. RESULTS: H&E staining revealed thermal coagulation zones in the dermis immediately after MRF treatment, with zone size increasing with higher power and longer pulse durations (p < 0.05). By Day 28, Collagen I and III densities and organization significantly improved, with the Collagen I/III ratio rising to 7.05 ± 1.21 in the treatment area (p < 0.01) and 3.90 ± 0.37 in the surrounding dermis (p < 0.001). Elastic fibers also showed increased density. mIHC staining demonstrated significant upregulation of MMP-1, MMP-3, and MMP-13 expression in treated and surrounding dermal regions by Day 7 (p < 0.01); however, by Day 28, MMP-1, MMP-9, and MMP-13 expression significantly decreased (p < 0.05), whereas MMP-3 remained elevated. Furthermore, expression levels of TGF-β, EGF, and Ki67 significantly increased by Day 28 (p < 0.05). mIHC analysis of the fibroblast marker FSP-1 coexpression, along with Western blot analysis of Collagen I, Collagen III, MMP-1, MMP-3, TGF-β, and EGF, revealed similar trends. Notably, significant expression of ADSC markers was detected at Day 7 posttreatment (p < 0.01). CONCLUSIONS: MRF predominantly promotes the synthesis of Collagen I and Collagen III, increasing the Collagen I/III ratio, and regulates the expression of MMP-1, MMP-3, MMP-9, TGF-β, and EGF. These factors collectively drive fibroblast activation, migration, and ECM remodeling. These changes are indicative of the potential for MRF to support skin regeneration and rejuvenation. Preliminary findings suggest that ADSCs may contribute to these regenerative processes.

Kilovoltage therapy is a valid treatment option for basal cell carcinomas (BCC), resulting in tumor control rates and cosmetic outcomes comparable to surgery. The aim was to report patient reported satisfaction as well as professional evaluation of cosmesis six months after treatment. From January 2020 to December 2023 a nationwide prospective study was conducted for patients with BCC in the facial region consecutively referred for kilovoltage therapy in five of six Danish cancer centers. Kilovoltage therapy, predominantly 70-100 kV, was delivered as either 51 Gy/17fx or 45 Gy/10fx. A follow-up consultation was performed six months after treatment, where patient satisfaction and professional evaluation were registered. In total 932 patients were included and of these 900 patients (97%) were either satisfied or very satisfied with the cosmetic outcome, which correlated with the professional evaluation (p < 0.001), in which 97% had no or minor skin changes. In univariate analysis, the following factors did not impact patient reported satisfaction with cosmesis: age (p = 0.05), sex (p = 0.2), current smoking (p = 0.2), field size diameter (p = 0.6) or fractionation schedule (p = 0.8). Altogether, 97% were satisfied with the cosmetic result six months after hypofractionated kilovoltage therapy for BCC, which correlated well with the professional objective evaluation.