Should we instruct patients to rub topical agents into skin? The evidence

Exposure to organophosphorus compounds: best practice in managing timely, effective emergency responses

Increasing indications, reports and studies demonstrate that threats from the deliberate use of chemical weapons remain high and are evolving. One of the deadliest classes of chemical weapons are the organophosphorus nerve agents. It is now clear that both state and non-state actors have the ability to deploy and use these types of weapons against individuals and the wider civilian population posing a real and significant threat. The objective of this article is to provide an overview of the issues impacting on a timely critical response to the accidental or deliberate release of Organophosphorus Nerve Agents in order to enhance the understanding of their effects and provide guidance on how first responders might better treat themselves or victims of exposure through a discussion of available evidence and best practices for rapid skin decontamination. The article also examines use of the current nomenclature of 'wet' and 'dry' to describe different forms of decontamination. One of the key conclusions of this article is that adequate preparedness is essential to ensuring that responders are trained to understand the threat posed by Organophosphorus Nerve Agents as well as how to approach a contaminated environment. A key aspect to achieving this will be to ensure that generic medical countermeasures are forward-deployed and available, preferably within minutes of a contamination and that first responders know how to use them.

Carbon dioxide foam bubbles enhance skin penetration through the stratum corneum layer with mechanical mechanism

Topical skin formulations often include penetration enhancers that interact with the outer stratum corneum (SC) layer to chemically enhance diffusion. Alternatively, penetration can be mechanically enhanced with simple rubbing in the presence of solid particles sometimes included to exfoliate the top layers of the SC. Our goal was to evaluate micron-sized carbon dioxide bubbles included in a foamed moisturizing formulation as a mechanical penetration enhancement strategy. We show that moisturizing foam bubbles cause an increase in SC formulation penetration using both mechanical and spectroscopic characterization. Our results suggest viscous liquid film drainage between coalescing gaseous bubbles creates local regions of increased hydrodynamic pressure in the foam liquid layer adjacent to the SC surface that enhances treatment penetration. An SC molecular diffusion model is used to rationalize the observed behavior. The findings indicate marked increased levels of treatment concentration in the SC at 2 h and that persists to 18 h after exposure, far exceeding non-foamed treatments. The study suggests an alternate strategy for increasing formulation penetration with a non-chemical mechanism.

Effect of massage on retinol skin penetration

Topical administration of active substances may be promoted by optimizing not only the vehicle formulation but also the application protocol. The formulation aspects are widely studied in the literature while a few works are dedicated to the development of application methods. In this context, we studied an application protocol usable as a part of skincare routine by investigating the effect of massage on the skin penetration of retinol. Retinol is a lipophilic molecule widely used as an anti-ageing firming agent in cosmetic formulations. Massage was applied to pig skin explants mounted to Franz diffusion cells after or before the deposit of the retinol-loaded formulation. Thetype of skin massage (roll or rotary type) and its duration were varied.The massage protocol had a significant influence on retinol skin penetration. Due to its highly lipophilic character, retinol accumulated into the stratum corneum but, depending on the massage protocol, a significant retinol concentration was obtained after 4 hours in epidermis and dermis layers. Results showed that the roll-type massage was significantly more efficient than the rotary process that exhibited little effect on retinol cutaneous penetration. Such results could be interesting for the development of massage devices in association with cosmetic formulations.

Tofacitinib Loaded Squalenyl Nanoparticles for Targeted Follicular Delivery in Inflammatory Skin Diseases

Tofacitinib (TFB), a Janus kinase inhibitor, has shown excellent success off-label in treating various dermatological diseases, especially alopecia areata (AA). However, TFB's safe and targeted delivery into hair follicles (HFs) is highly desirable due to its systemic adverse effects. Nanoparticles (NPs) can enhance targeted follicular drug delivery and minimize interfollicular permeation and thereby reduce systemic drug exposure. In this study, we report a facile method to assemble the stable and uniform 240 nm TFB loaded squalenyl derivative (SqD) nanoparticles (TFB SqD NPs) in aqueous solution, which allowed an excellent loading capacity (LC) of 20%. The SqD NPs showed an enhanced TFB delivery into HFs compared to the aqueous formulations of plain drug in an ex vivo pig ear model. Furthermore, the therapeutic efficacy of the TFB SqD NPs was studied in a mouse model of allergic dermatitis by ear swelling reduction and compared to TFB dissolved in a non-aqueous mixture of acetone and DMSO (7:1 v/v). Whereas such formulation would not be acceptable for use in the clinic, the TFB SqD NPs dispersed in water illustrated a better reduction in inflammatory effects than plain TFB's aqueous formulation, implying both encouraging good in vivo efficacy and safety. These findings support the potential of TFB SqD NPs for developing a long-term topical therapy of AA.

Acute Effects of Transdermal Administration of Jojoba Oil on Lipid Metabolism in Mice

Background and objectives: Aroma therapy is a complementary therapy using essential oils diluted with carrier oils. Jojoba oils have been widely used as carrier oils. However, limited information is available regarding their effects on blood biochemical parameters. This study aimed to investigate the effect of transdermal administration of jojoba oil on blood biochemical parameters in mice. Materials and Methods: Eight-week-old male hairless mice were randomly divided into naïve control and treatment groups. In the treatment group, mice were topically administered 4 μL of jojoba oil, per gram of body weight, on the dorsa 30 min before euthanasia. Thereafter, serum biochemical parameters were assayed, and gene expression was analyzed in various tissues via a real-time polymerase chain reaction. Results: Serum non-esterified fatty acid (NEFA) levels increased significantly 30 min after topical application of jojoba oil (p < 0.05). Atgl was significantly upregulated in the liver (p < 0.05), and Atgl upregulation in the liver was positively correlated with serum NEFA levels (r = 0.592, p < 0.05). Furthermore, a trend of decreasing fatty acid trafficking-related gene (FABPpm, FATP-1, FATP-3, and FATP-4) expression in the skin after topical application of jojoba oil (p = 0.067, 0.074, 0.076, and 0.082, respectively) was observed. Conclusions: Serum NEFA levels were elevated 30 min after transdermal administration of jojoba oil. The mechanisms of elevated serum NEFA levels might be related to both enhanced lipolysis in the liver and reduced fatty acid trafficking in the skin.