Ultraviolet B radiation (UVB) has profound effects on human skin that results in a broad spectrum of immunological local and systemic responses and is the major cause of skin carcinogenesis. One important area of study in photobiology is how UVB is translated into effector signals. As the skin is exposed to UVB light, subcellular microvesicle particles (MVP), a subtype of bioactive extracellular vesicles, are released causing a variety of local and systemic immunological effects. In this review, we highlight keratinocyte MVP release in keratinocytes in response to UVB. Specifically, Platelet-activating factor receptor agonists generated by UVB result in MVP released from keratinocytes. The downstream effects of MVP release include the ability of these subcellular particles to transport agents including the glycerophosphocholine-derived lipid mediator Platelet-activating factor (PAF). Moreover, even though UVB is only absorbed in the epidermis, it appears that PAF release from MVPs also mediates systemic immunosuppression and enhances tumor growth and metastasis. Tumor cells expressing PAF receptors can use this mechanism to evade chemotherapy responses, leading to treatment resistance for advanced cancers such as melanoma. Furthermore, novel pharmacological agents provide greater insight into the UVB-induced immune response pathway and a potential target for pharmacological intervention. This review outlines the need to more clearly elucidate the mechanism linking UVB-irradiation with the cutaneous immune response and its pathological manifestations. An improved understanding of this process can result in new insights and treatment strategies for UVB-related disorders from carcinogenesis to photosensitivity.

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The occurrence of non-melanoma skin cancer (NMSC) is closely linked with advanced age and ultraviolet-B (UVB) exposure. More specifically, the development of NMSC is linked to diminished insulin-like growth factor-1 (IGF-1) signaling from senescent dermal fibroblasts in geriatric skin. Consequently, keratinocyte IGF-1 receptor (IGF-1R) remains inactive, resulting in failure to induce appropriate protective responses including DNA repair and cell cycle checkpoint signaling. This allows UVB-induced DNA damage to proliferate unchecked, which increases the likelihood of malignant transformation. NMSC is estimated to occur in 3.3 million individuals annually. The rising incidence results in increased morbidity and significant healthcare costs, which necessitate identification of effective treatment modalities. In this review, we highlight the pathogenesis of NMSC and discuss the potential of novel preventative therapies. In particular, wounding therapies such as dermabrasion, microneedling, chemical peeling, and fractionated laser resurfacing have been shown to restore IGF-1/IGF-1R signaling in geriatric skin and suppress the propagation of UVB-damaged keratinocytes. This wounding response effectively rejuvenates geriatric skin and decreases the incidence of age-associated NMSC.

Introduction Anki is an application that capitalizes upon the techniques of spaced repetition and is increasingly utilized by medical students for examination preparation. This study examines the impact of Anki usage in a medical school curriculum on academic performance. Secondary objectives analyzed individual Anki utilization and a qualitative assessment of Anki use. Methods A cohort-control study was conducted at Boonshoft School of Medicine. One hundred thirty first-year medical students were enrolled in an Anki utilization training program from July 2021 to September 2021. Training included educational Anki courses and subsequent survey data collection over Anki usage. Data variables included all course final examinations, the Comprehensive Basic Science Exam (CBSE), individual Anki user statistics, nationally standardized exams scores, and Qualtrics surveys on student perceived ease of use. Results Seventy-eight students reported using Anki for at least one of the exams, and 52 students did not use Anki for any exam. Anki users scored significantly higher across all four exams: Course I (6.4%; p < 0.001); Course II (6.2%; p = 0.002); Course III (7.0%; p = 0.002); and CBSE (12.9%; p = 0.003). Students who reported higher dependency on Anki for studying performed significantly better on the Course I, II, and CBSE exams. Conclusion Anki usage may be associated with an increase in standardized examination scores. This supports Anki as an evidence-based spaced repetition and active retrieval learning modality for medical school standardized examinations. There was little correlation between its specific statistical markers and examination performance. This is pertinent to physicians and medical students alike as the learning and preservation of biomedical knowledge is required for examinations and effective clinical care.

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