Atopic dermatitis and vitamin D: facts and controversies

Patients with atopic dermatitis have genetically determined risk factors that affect the barrier function of the skin and immune responses that interact with environmental factors. Clinically, this results in an intensely pruriginous and inflamed skin that allows the penetration of irritants and allergens and predisposes patients to colonization and infection by microorganisms. Among the various etiological factors responsible for the increased prevalence of atopic diseases over the past few decades, the role of vitamin D has been emphasized. As the pathogenesis of AD involves a complex interplay of epidermal barrier dysfunction and dysregulated immune response, and vitamin D is involved in both processes, it is reasonable to expect that vitamin D's status could be associated with atopic dermatitis' risk or severity. Such association is suggested by epidemiological and experimental data. in this review, we will discuss the evidence for and against this controversial relationship, emphasizing the possible etiopathogenic mechanisms involved.Univ Brasilia UNB, Brasilia, DF, BrazilFed Dist Hlth State Dept SES DF, Brasilia, DF, BrazilUniv Brasilia HUB UNB, Brasilia Univ Hosp, Brasilia, DF, BrazilSão Paulo Fed Univ UNIFESP, Brasilia, DF, BrazilSão Paulo Fed Univ UNIFESP, Brasilia, DF, BrazilWeb of Scienc

Hardware Implementation of a Modified Delay-Coordinate Mapping-Based QRS Complex Detection Algorithm

We present a modified delay-coordinate mapping-based QRS complex detection algorithm, suitable for hardware implementation. In the original algorithm, the phase-space portrait of an electrocardiogram signal is reconstructed in a two-dimensional plane using the method of delays. Geometrical properties of the obtained phase-space portrait are exploited for QRS complex detection. In our solution, a bandpass filter is used for ECG signal prefiltering and an improved method for detection threshold-level calculation is utilized. We developed the algorithm on the MIT-BIH Arrhythmia Database (sensitivity of 99.82% and positive predictivity of 99.82%) and tested it on the long-term ST database (sensitivity of 99.72% and positive predictivity of 99.37%). Our algorithm outperforms several well-known QRS complex detection algorithms, including the original algorithm