Quantification of ultraviolet (UV) radiation in the shade and in direct sunlight.

Ultraviolet (UV) radiation is associated with negative health effects, including sun damage and skin cancer. The purpose of this study is to compare the protective effects of the shade provided by a sun umbrella versus that provided by a tree. Sun sensors that register the level and dose of UV radiation were placed in the shade and in direct sunlight. Measurements were recorded every half hour between the hours of 12:30 p.m. and 3:00 p.m. in Sacramento, California. The results suggest that the level of UV radiation in the shade is not zero. The sensors located in tree shade indicated that over 5% of UV radiation was detected in the shade. The sensors located in sun-umbrella shade showed that greater than 17% of UV radiation reached the shade. The sun sensors used in our study collected UV radiation data relevant to UV index; however, they did not differentiate between UVA, UVB, visible, and infrared light. The amount of UV radiation detected in the shade is not zero, thus regular sunscreen use and other sun protective practices should be followed to reduce the risk of sun damage and skin cancer.

Human sebum requires de novo lipogenesis, which is increased in acne vulgaris and suppressed by acetyl-CoA carboxylase inhibition.

Sebum plays important physiological roles in human skin. Excess sebum production contributes to the pathogenesis of acne vulgaris, and suppression of sebum production reduces acne incidence and severity. We demonstrate that sebum production in humans depends on local flux through the de novo lipogenesis (DNL) pathway within the sebocyte. About 80 to 85% of sebum palmitate (16:0) and sapienate (16:1n10) were derived from DNL, based on stable isotope labeling, much higher than the contribution of DNL to triglyceride palmitate in circulation (~20%), indicating a minor contribution by nonskin sources to sebum lipids. This dependence on local sebocyte DNL was not recapitulated in two widely used animal models of sebum production, Syrian hamsters and Göttingen minipigs. Confirming the importance of DNL for human sebum production, an acetyl-CoA carboxylase inhibitor, ACCi-1, dose-dependently suppressed DNL and blocked synthesis of fatty acids, triglycerides, and wax esters but not free sterols in human sebocytes in vitro. ACCi-1 dose-dependently suppressed facial sebum excretion by ~50% (placebo adjusted) in human individuals dosed orally for 2 weeks. Sebum triglycerides, wax esters, and free fatty acids were suppressed by ~66%, whereas non-DNL-dependent lipid species, cholesterol, and squalene were not reduced, confirming selective modulation of DNL-dependent lipids. Last, individuals with acne vulgaris exhibited increased sebum production rates relative to individuals with normal skin, with >80% of palmitate and sapienate derived from DNL. These findings highlight the importance of local sebocyte DNL for human skin sebaceous gland biology and illuminate a potentially exploitable therapeutic target for the treatment of acne vulgaris.

Progestins and acne vulgaris: a review.

The role of exogenous progestin in the development of acne is unclear. Progestins are known for their androgenic potential, but newer generations of progestins have low or anti-androgenic activity. This review will evaluate the association between progestins found in hormonal long-acting reversible contraceptives (intrauterine devices and subdermal implants) and acne, as well as the role of oral contraceptives in acne management. Our review demonstrates that the cause and effect relationship between progestins and acne is difficult to establish and future studies that seek to understand how progestins modulate acne are necessary.

Randomized and controlled pilot study of the pragmatic use of mobile phone based follow up of actinic keratoses treated with topical 5-fluorouracil.

Store-and-forward teledermatology involves transmission of a patient's images to a healthcare provider and subsequent response from the provider about the diagnosis or management. Furthermore, teledermatology in which mobile phones (e.g. smartphones) are utilized for communication between the patient and their provider is referred to as mobile-teledermatology. In this study, we investigate the use of mobile-teledermatology in the management of actinic keratoses. We demonstrate that mobile-teledermatology may enhance communication between the patient and their provider when managing cutaneous disease and that even individuals in older age groups are highly satisfied with this type of follow up.

Emerging Therapies for Acne Vulgaris.

As we gain a greater understanding of acne pathogenesis, both new agents as well as new uses for established drugs are being considered for the treatment of acne vulgaris. Multiple clinical trials assessing new formulations or combinations of established acne treatments have been conducted, and novel uses of antimicrobials such as modified diallyl disulfide oxide and nitric oxide are being assessed in clinical trials. There are also a multitude of new therapies currently being studied that target the inflammatory cascade of acne pathogenesis, including sebosuppressive and anti-inflammatory phytochemicals, and  small molecule inhibitors targeting sebaceous glands and enzymes, among others. Laser and light therapy is also being modified for the treatment of acne through combination methods with metal nanoshells and vacuum assistance. Probiotics have gained popularity in medicine as greater knowledge of the microbiome and its effects on multiple organ systems is being elucidated. Studies describing the positive effects of certain ammonia-oxidizing bacterial strains in the regulation of the skin's inflammatory response are ongoing. Therapies for acne are constantly evolving and current gold-standard acne therapy may be supplemented with novel treatment modalities in the near future.