Future prospects in 3-dimensional (3D) technology and Mohs micrographic surgery.

The advancement of three-dimensional (3D) bioprinting has allowed for changes within the field of dermatology. Skin bioprinting is a transformative technology used to fabricate biomimetic scaffold architectures which mimic human skin. This paper briefly discusses three major types of biological printing: inkjet-based bioprinting, laser-assisted bioprinting and pressure-assisted bioprinting in regard to skin bioprinting for Mohs application. This manuscript reviews the basic principles of 3D printing (inkjet-based bioprinting, laser-assisted bioprinting and pressure-assisted bioprinting), current 3D skin bioprinting applications and methods, and perspectives on using 3D printing for Mohs surgery.

Exogenous ochronosis associated with hydroquinone: a systematic review.

Exogenous ochronosis is a potential side effect associated with hydroquinone, and treatment is often unsatisfactory. Our study objectives were to review data on hydroquinone-associated ochronosis to determine risk factors for patients experiencing this adverse event. On September 27, 2020 (MEDLINE/PubMed), and October 30, 2020 (Scopus and Web of Science), databases were searched for "ochronosis + hydroquinone" by both authors to reduce risk basis. PRISMA reporting guidelines were used to select 56 articles with a total of 126 patients with hydroquinone-associated ochronosis. Included articles described hydroquinone-associated ochronosis. Articles were excluded if they had irrelevant content, were non-English language text, and were non-case studies. Full text articles were assessed and recorded. Cross-tabulation analysis was performed on categorical data, and Fisher exact test was performed. Ochronosis was most often reported in middle-aged women (53.2%), of African descent (45.2%), Black races (55.5%), and Fitzpatrick skin types V-VI (52.4%). It was most frequently reported with unknown and hydroquinone concentrations greater than 4% (32.5 and 35.7% cases, respectively). Median duration of use was 5 years, with only four cases reported with courses 3 months or shorter and eight cases reported with use 1 year or less. All patients presented with facial blue-black or gray-blue macules in a reticulate, lace-like fashion. Histopathology consistently showed solar elastosis and brownish-yellow, 'banana-shaped' fibers between degenerated collagen fibers of the papillary dermis. Based on these findings, we conclude that hydroquinone in concentrations above 4% and in treatment courses longer than 3 months may be associated with new-onset ochronosis.

Are There Mobile Applications Related to Nail Disorders?

The role of mobile applications (apps) for patient education is expanding, with little inquiry evaluating the quantity and quality of nail disorder apps. Our objective was to investigate iOS (Apple's iPhone Operating System) and Android apps to determine the types of nail health apps that are available for patient education. A standard app analytics and market data tool was used to search and analyze iOS and Android nail apps for several nail health, psoriasis, and hair loss keywords.

Bioinformatics and immunoinformatics to support COVID-19 vaccine development.

Severe acute respiratory syndrome coronavirus 2 has infected over 109 000 000 people with 2 423 443 deaths as of February 17, 2021. Currently, there are no approved or consistently effective treatments, and conventional vaccines may take several years for development and testing. In silico methods of bioinformatics, vaccinogenomics, immunoinformatics, structural biology, and molecular simulations can be used for more rapid and precise vaccine design. This paper highlights two major immunoinformatics strategies that are used in designing novel and effective vaccines and therapeutics: reverse vaccinology and structural vaccinology.

Use of 3D printing to support COVID-19 medical supply shortages: a review.

The novel coronavirus, COVID-19, created a pandemic with significant mortality and morbidity which poses challenges for patients and healthcare workers. The global spread of COVID-19 has resulted in shortages of personal protective equipment (PPE) leaving frontline health workers unprotected and overwhelming the healthcare system. 3D printing is well suited to address shortages of masks, face shields, testing kits and ventilators. In this article, we review 3D printing and suggest potential applications for creating PPE for healthcare workers treating COVID-19 patients. A comprehensive literature review was conducted using PubMed with keywords "Coronavirus disease 2019", "COVID-19", "severe acute respiratory syndrome coronavirus 2", "SARS-CoV-2", "supply shortages", "N95 respirator masks", "personal protective equipment", "PPE", "ventilators", "three-dimensional model", "three-dimensional printing" "3D printing" and "ventilator". A summary of important studies relevant to the development of 3D-printed clinical applications for COVID-19 is presented. 3D technology has great potential to revolutionize healthcare through accessibility, affordably and personalization.

A Review of 3-Dimensional Skin Bioprinting Techniques: Applications, Approaches, and Trends.

BACKGROUND: Tissue engineering is used to fabricate 3-dimensional (3D) artificial scaffolds to create a microenvironment that mimics human tissue. Bioprinting uses biomaterials, cells, and/or bioink to fabricate prospective scaffolds to mirror the structural, compositional, and functional aspects of the skin. Various bioprinting methods (inkjet-based bioprinting, pressure-assisted bioprinting, and laser-assisted bioprinting) have been used for regenerative wound repair and have been characterized based on biocompatibility, cellular microenvironment, cell proliferation, vitality, and morphology. OBJECTIVE: This article reviews the basic principles of 3D printing, current 3D skin bioprinting applications and approaches, and future directions for regenerative medical skin constructs. METHODS: A comprehensive literature review was conducted using PubMed with keywords "three-dimensional printing," "dermatologic surgery," "bioprinting," "reconstructive surgical procedures," "wound healing," "skin grafts," "skin scaffolds," "tissue reconstruction," and "tissue engineering." RESULTS: A summary of the different applications and 3-dimensional skin bioprinting techniques is presented. In addition, synthetic, natural, and combination polymers are reviewed. Advantages, disadvantages, indications, and approaches are discussed in depth. CONCLUSION: Skin grafting is a dynamic technique of dermal reconstruction that can be successful with comprehensive knowledge of skin bioprinting methods.

Bone regeneration in critical bone defects using three-dimensionally printed ß-tricalcium phosphate/hydroxyapatite scaffolds is enhanced by coating scaffolds with either dipyridamole or BMP-2.

Bone defects resulting from trauma or infection need timely and effective treatments to restore damaged bone. Using specialized three-dimensional (3D) printing technology we have created custom 3D scaffolds of hydroxyapatite (HA)/beta-tri-calcium phosphate (ß-TCP) to promote bone repair. To further enhance bone regeneration we have coated the scaffolds with dipyridamole, an agent that increases local adenosine levels by blocking cellular uptake of adenosine. Nearly 15% HA:85% ß-TCP scaffolds were designed using Robocad software, fabricated using a 3D Robocasting system, and sintered at 1100°C for 4 h. Scaffolds were coated with BMP-2 (200 ng mL-1 ), dypiridamole 100 µM or saline and implanted in C57B6 and adenosine A2A receptor knockout (A2AKO) mice with 3 mm cranial critical bone defects for 2-8 weeks. Dipyridamole release from scaffold was assayed spectrophotometrically. MicroCT and histological analysis were performed. Micro-computed tomography (microCT) showed significant bone formation and remodeling in HA/ß-TCP-dipyridamole and HA/ß-TCP-BMP-2 scaffolds when compared to scaffolds immersed in vehicle at 2, 4, and 8 weeks (n = 5 per group; p ≤ 0.05, p ≤ 0.05, and p ≤ 0.01, respectively). Histological analysis showed increased bone formation and a trend toward increased remodeling in HA/ß-TCP- dipyridamole and HA/ß-TCP-BMP-2 scaffolds. Coating scaffolds with dipyridamole did not enhance bone regeneration in A2AKO mice. In conclusion, scaffolds printed with HA/ß-TCP promote bone regeneration in critical bone defects and coating these scaffolds with agents that stimulate A2A receptors and growth factors can further enhance bone regeneration. These coated scaffolds may be very useful for treating critical bone defects due to trauma, infection or other causes. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 366-375, 2017.

First-trimester maternal dried blood Down syndrome screening marker levels in early pregnancy loss.

OBJECTIVE: To determine the association of free beta hCG and PAPP-A measured during first-trimester Down syndrome risk assessment with early pregnancy loss when blood is drawn prior to scheduled ultrasound. METHODS: Maternal dried blood samples were collected prior to the ultrasound exam for Down syndrome risk assessment. Free beta hCG and PAPP-A levels in 55 patients who experienced loss of pregnancy prior to their scheduled ultrasound appointment were compared to 6464 control pregnancies using logistic regression. RESULTS: Low levels of free beta hCG and PAPP-A were associated with increased risk of early pregnancy loss. The detection rate of early pregnancy loss for a fixed 5% false-positive rate using free beta alone, PAPP-A alone and a combination of the two were 47, 36 and 49%, respectively. CONCLUSION: Free beta hCG and PAPP-A can identify pregnancies at increased risk for early pregnancy loss. More studies are needed to determine whether further evaluation of these pregnancies prior to the scheduled ultrasound is warranted.