In vitro determination of Mexican Mestizo hair shaft diameter using optical coherence tomography.

BACKGROUND: Mexican mestizo population has a pluriethnic mixture of Amerindian, European and African ancestry, predominant in most Latin American countries. Until now, there are no reports about hair characteristics in this population, necessary to define normal values, for hair diseases evaluation and comparison among other ethnic groups. METHODS: The VivoSight® swept-source multibeam optical coherence tomography system was used to evaluate hair diameter and shape in 30 females. Three hair samples from each volunteer were measured transversely along three distances, generating nine cross-sectional images, two measurements per image and 18 measurements per patient for a total of 540 diameter measurements. RESULTS: Minimum hair diameter (n = 540) was 0.06 mm while maximum was 0.14 mm. Mean diameter was 0.10 ± 0.01 mm as compared with Asian hair, which ranges from 0.08 mm to 0.12 mm. On morphological analysis, Mexican Mestizo hair tends to have a round shape with homogenous diameters, resembling Caucasian and Asian hair. CONCLUSION: Mexican hair is similar to Asian hair in diameter and shape and can be classified as 'thick' hair, which make it more resistant and with more volume. Cosmetic products intended to improve hair care in this population must to consider this characteristic.

Optical coherence tomography for assessment of epithelialization in a human ex vivo wound model.

The ex vivo human skin wound model is a widely accepted model to study wound epithelialization. Due to a lack of animal models that fully replicate human conditions, the ex vivo model is a valuable tool to study mechanisms of wound reepithelialization, as well as for preclinical testing of novel therapeutics. The current standard for assessment of wound healing in this model is histomorphometric analysis, which is labor intensive, time consuming, and requires multiple biological and technical replicates in addition to assessment of different time points. Optical coherence tomography (OCT) is an emerging noninvasive imaging technology originally developed for noninvasive retinal scans that avoids the deleterious effects of tissue processing. This study investigated OCT as a novel method for assessing reepithelialization in the human ex vivo wound model. Excisional ex vivo wounds were created, maintained at air-liquid interface, and healing progression was assessed at days 4 and 7 with OCT and histology. OCT provided adequate resolution to identify the epidermis, the papillary and reticular dermis, and importantly, migrating epithelium in the wound bed. We have deployed OCT as a noninvasive tool to produce, longitudinal "optical biopsies" of ex vivo human wound healing process, and we established an optimal quantification method of re-epithelialization based on en face OCT images of the total wound area. Pairwise statistical analysis of OCT and histology based quantifications for the rate of epithelialization have shown the feasibility and superiority of OCT technology for noninvasive monitoring of human wound epithelialization. Furthermore, we have utilized OCT to evaluate therapeutic potential of allogeneic adipose stem cells revealing their ability to promote reepithelialization in human ex vivo wounds. OCT technology is promising for its applications in wound healing and evaluation of novel therapeutics in both the laboratory and the clinical settings.

Sun protection for infants: parent behaviors and beliefs in Miami, Florida.

Children who are not adequately protected from the sun have an increased risk for developing skin cancers later in life. The primary objective of this study was to determine the sun protection behaviors that black and Hispanic parents in Miami, Florida, employ in infants younger than 6 months. Secondary objectives included determining if this patient population is at risk for infant sunburns and tanning, beliefs among parents regarding sunscreen's efficacy in the prevention of skin cancers, and limitations of sunscreen use. An institutional review board-approved survey was administered to parents presenting to the University of Miami general pediatrics clinic. The main outcome measure was the self-reported consistency with which parents employed each of 6 sun protection strategies in infants. The results of this study highlight some potential shortcomings in current practices in sun protection for black and Hispanic infants.

Laser treatment of granuloma annulare: a review.

Granuloma annulare (GA) is a benign asymptomatic dermatosis that typically manifests in papules arrayed in annular arrangements. Many methods of treatment have been used with variable degrees of success, but finding a consistent and long-term treatment has proven a challenge. This study was conducted in order to review and evaluate the latest published research on the use of lasers in the treatment of GA. A systematic search of the National Library of Medicine's PubMed database was performed to identify relevant articles. Seven reports met the inclusion criteria for the review. Evidence for the use of pulsed dye laser, fractional photothermolysis, and excimer laser in the treatment of GA was found. Findings are limited by a lack of well-designed clinical trials objectively evaluating the use of lasers in the treatment of GA. The literature review found a number of case reports and case series that report successful outcomes of the use of lasers in the treatment of GA. The promising results reported in the literature, coupled with the lack of a well-designed review on this topic, reflect the importance of this article to the dermatologic literature as it emphasizes the need for larger and better-designed studies on the use of lasers to treat GA.