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Actinic keratosis (AK) is a lesion that arises as a result of excessive exposure to solar radiation and appearing predominantly on Fitzpatrick phototype I and II skin. Given that some AKs evolve into squamous cell carcinoma, these lesions are considered premalignant in nature, occurring mostly in elderly men and immunosuppressed individuals chronically exposed to ultraviolet (UV) radiation. There are several mechanisms for the formation of AKs; among them are oxidative stress, immunosuppression, inflammation, altered proliferation and dysregulation of cell growth, impaired apoptosis, mutagenesis, and human papillomavirus (HPV). Through the understanding of these mechanisms, several treatments have emerged. Among the options for AK treatment, the most commonly used include 5-fluorouracil (5-FU), cryotherapy, diclofenac, photodynamic therapy (PDT), imiquimod (IQ), retinoids, and ingenol mebutate (IM). There have been recent advances in the treatment options that have seen the emergent use of newer agents such as resiquimod, betulinic acid, piroxicam, and dobesilate. The combination between therapies has presented relevant results with intention to reduce duration of therapy and side effects. All AK cases must be treated because of their propensity to transform into malignancy and further complicate treatment. In addition to medical or surgical care, education about sun exposure prevention remains the best and most cost-effective method for AK prevention. The objective of this article is to conduct a literature review of the clinical presentation of AK including advances in treatment options available.

Free radicals are unstable chemical species, highly reactive, being formed by cellular entities of different tissues. Increased production of these species without proper effective action of endogenous and exogenous antioxidant systems, generates a condition of oxidative stress, potentially provider of skin disorders that extend from functional impairments (skin cancer, dermatitis, chronic and acute inflammatory processes) even aesthetic character, with the destruction of structural proteins and cellular changes with the appearance of stains, marks and lines of expressions and other signs inherent to the intrinsic and extrinsic skin aging process. The antioxidants are chemical substances commonly used in clinical practice for topical application and may contribute in the fight against the radical species responsible for many skin damage. This paper summarized the main evidence of the benefits brought by the topical application of antioxidants in the skin, considering the amplitude of the indicative performance of antioxidant activity by in vitro and ex-vivo tests as well as in vivo tests. It is recognized that a breadth of product performance tests should be explored to truly identify the effectiveness of antioxidant products for an anti-aging effect.

The cutaneous route is attractive for the delivery of drugs in the treatment of a wide variety of diseases. However the stratum corneum (SC) is an effective barrier that hampers skin penetration. Within this context, liposomes emerge as a potential carrier for improving topical delivery of therapeutic agents. In this review, we aimed to discuss key aspects for the topical delivery by drug-loaded liposomes. Phospholipid type and phase transition temperature have been shown to affect liposomal topical delivery. The effect of surface charge is subject to considerable variation depending on drug and composition. In addition, modified vesicles with the presence of components for permeation enhancement, such as surfactants and solvents, have been shown to have a considerable effect. These liposomes include: Transfersomes, Niosomes, Ethosomes, Transethosomes, Invasomes, coated liposomes, penetration enhancer containing vesicles (PEVs), fatty acids vesicles, Archaeosomes and Marinosomes. Furthermore, adding polymeric coating onto liposome surface could influence cutaneous delivery. Mechanisms of delivery include intact vesicular skin penetration, free drug diffusion, permeation enhancement, vesicle adsorption to and/or fusion with the SC, trans-appendageal penetration, among others. Finally, several skin conditions, including acne, melasma, skin aging, fungal infections and skin cancer, have benefited from liposomal topical delivery of drugs, with promising in vitro and in vivo results. However, despite the existence of some clinical trials, more studies are needed to be conducted in order to explore the potential of liposomes in the dermatological field.

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Bleaching gels with remineralizing agents e116

Background Topical tretinoin cream is the gold standard treatment for skin ageing, particularly photoaging. The purpose of tretinoin peel was to obtain similar results, but in a shorter time, however, there have been few controlled trials on its effectiveness. Objective To compare efficacy and safety of tretinoin 0.05% cream and 5% as a peeling agent on photoaging and field cancerization of the forearms. Methods Clinical trial with therapeutic intervention, prospective, randomized (computer‐generated randomization list), parallel, comparative (intrasubject) and evaluator‐blinded (except for histology and immunohistochemistry), including 24 women (48 forearms) aged over 60 years who have not undergone hormone replacement and categorized as Fitzpatrick skin phototype II or III. The forearms of the participants were randomized for treatment with 0.05% tretinoin cream three nights a week, or 5% tretinoin peel every 2 weeks. The opinion of the participant, severity of photoaging, corneometry, profilometry, high‐frequency ultrasound, histology (haematoxylin–eosin and Verhoeff stainings) and immunohistochemistry (p53, bcl‐2, Ki67 and collagen I) were assessed. Results One participant dropped out. The mean photoaging score reduced 20% and the mean actinic keratosis (AK) count reduced 60% with no difference between treatments. Three efficacy parameters showed opposite effects between the tretinoin treatments (P < 0.05%): (i) thickness of the corneal layer decreased with 0.05% tretinoin and increased by 5%; (ii) dermis echogenicity increased by 0.05% and decreased by 5% and (iii) Ki67 expression increased by 0.05% and decreased by 5%. There was good tolerability for both regimens. Conclusion Tretinoin as a cream 0.05% or peeling (5%) is safe and effective for the treatment of moderate photoaging and forearm field cancerization. The cream was superior in improving ultrasonographic parameters of ageing. Peeling was shown a superior performance in the stabilization of field cancerization.