Microchanneling and ultrasonic delivery of gold and platinum nanoparticles for selective photothermolysis of sebaceous follicles in the treatment of acne: a pilot study using porcine skin.

PURPOSE: Several treatment options for acne vulgaris are limited by their associated adverse effects. An innovative approach involves introducing light-absorbing nanoparticles into sebaceous follicles before destroying the follicles using selective photothermolysis. We aimed to investigate efficient methods for introducing gold and platinum nanoparticles into sebaceous follicles and to identify suitable laser equipment and parameters for the effective destruction of these follicles. METHODS: We used porcine skin as the experimental model. We compared the efficacies of a thulium laser, ultrasound, and manual massage and evaluated the optimal method for delivering nanoparticles in close proximity to sebaceous follicles. Subsequently, a 1064-nm-wavelength neodymium-doped yttrium aluminum garnet (Nd: YAG) laser was employed to induce selective photothermolysis. We compared different parameters to identify the optimal pulse duration and fluence of the Nd: YAG laser. The extent of penetration and destruction of sebaceous follicles was assessed using hematoxylin and eosin (H&E) staining, and a numerical evaluation was conducted. RESULTS: H&E staining showed that irradiation with a long-pulsed Nd: YAG laser following a combination of thulium laser and sonophoresis effectively destroyed sebaceous follicles, with destruction rates exceeding 50%. These results were valid with a long pulse duration and a high fluence of the Nd: YAG laser. CONCLUSION: This study demonstrated that sebaceous follicles can be effectively destroyed through a mixture of gold and platinum nanoparticle delivery by a combination of microchanneling and sonophoresis, followed by selective thermal damage induced by a 1064-nm long-pulsed high-fluence Nd: YAG laser.

Nine cases of chronic hand and foot eczema treated with baricitinib.

Chronic hand and foot eczema (CHFE) is a common inflammatory disorder that generally lasts for over 3 months. If it is intractable to topical agents, systemic immunomodulators can be considered; however, they are not suitable for long-term management because of their adverse effects. Baricitinib is an oral Janus kinase inhibitor that has been approved for the treatment of moderate-to-severe atopic dermatitis. However, its effect on CHFE has rarely been described. Herein, we report nine cases of recalcitrant CHFE that were treated with baricitinib after an inadequate response to low-dose ciclosporin. All patients had more than moderate improvement within 2-8 weeks without serious adverse effects.