Chimerism involving a RB1 pathogenic variant in monochorionic dizygotic twins with twin-twin transfusion syndrome.

We report the first case of blood chimerism involving a pathogenic RB1 variant in naturally conceived monochorionic-dizygotic twins (MC/DZ) with the twin-twin-transfusion syndrome (TTTS), presumably caused by the exchange of stem-cells. Twin A developed bilateral retinoblastoma at 7 months of age. Initial genetic testing identified a de novo RB1 pathogenic variant, with a 20% allelic ratio in both twins' blood. Subsequent genotyping of blood and skin confirmed dizygosity, with the affected twin harboring the RB1 pathogenic variant in skin and blood, and the unaffected twin carrying the variant only in blood.

Lichenoid drug eruption after treatment with ixekizumab for plaque psoriasis.

Lichen Planus (LP), the prototype of lichenoid dermatoses, is an idiopathic, T cell-mediated, autoimmune, inflammatory disease. It may affect the skin, hair, nails, and mucous membranes. Many clinical variants of LP have been described, including lichenoid drug eruption or drug induced LP, associated with a myriad of culprit medications. We describe a 63-year-old woman with longstanding psoriasis effectively controlled with ixekizumab, who developed lichenoid drug eruption . Her lichen planus lesions improved after treatment discontinuation and the patient was started on an IL23 inhibitor to treat her psoriasis through an alternative mechanism of action. Our report adds to the literature and provides insight into the complex pathophysiology of lichen planus.

Departmental h-Index: Evidence for Publishing Less?

PURPOSE: The h-index is an established method for determining an individual faculty member's impact on the scientific literature. The purpose of this study was to measure and describe over time the combined h-index of a large university medical imaging department. MATERIALS AND METHODS: All faculty members from the Department of Medical Imaging, University of Toronto, were identified from administrative records for 6 separate years between 2000-2014. Individual members' and the departmental h-index were calculated using citation data from the Scopus database. Descriptive univariate statistics were reported. Factors contributing to the change in departmental h-index over time were assessed using linear regression analysis. RESULTS: The number of faculty members increased from 117 in 2000 to 186 in 2014. The departmental h-index increased from 48 in 2000 to 142 in 2014. During this time period, the median h-index for faculty members increased from 4 (interquartile range 2-8) to 10 (interquartile range 5-19). Regression analysis revealed that for every additional staff member, the departmental h-index increased by 1.4 (standard error = 0.1, P < .01), whereas, by increasing the median h-index of members by 1 the departmental h-index increased by 15.7 (standard error = 0.6, P < .01). CONCLUSION: Our study suggests that to increase a department's h-index, it is important to foster impactful research from within the faculty ranks of the department. The h-index of academic radiology departments is a meaningful tool that allows for evaluation from within and against other academic centres.

Comparison of psoriasis guidelines for use of apremilast in the United States and Europe: a critical appraisal and comprehensive review.

PURPOSE: This review article serves to compare global dermatologic organizations and the available clinical practice guidelines for the use of apremilast in the treatment of psoriasis. MATERIALS AND METHODS: Guidelines from the American Academy of Dermatology (AAD), the National Psoriasis Foundation (NPF), the European S3, the National Institute for Health and Care Excellence (NICE), the French Society of Dermatology (SFD), the Swiss S1, and Italy were reviewed and compared. RESULTS: Of the American and European guidelines available for use of apremilast, several organizations are in agreement regarding the dosage of apremilast, but there are significant disagreements concerning matters such as medication indication, pretreatment laboratory testing, and contraindications to therapy. CONCLUSION: Apremilast is an effective and well-tolerated treatment option for patients with psoriasis and should be considered in the line of therapy that dermatologists discuss with their patients, especially those with contraindications to other systemic therapies such as biologics. Consideration should be given to the evidence-based recommendations of global dermatology organizations to help guide therapeutic decisions.

Transmissible Cancers and Immune Downregulation in Tasmanian Devil (Sacrophilus harrisii) and Canine Populations.

Known as devil facial tumor disease (DFTD) and canine transmissible venereal tumor (CTVT), transmissible cancer occurs in both Tasmanian devil and canine populations, respectively. Both malignancies show remarkable ability to be transmitted as allografts into subsequent hosts. How DFTD and CTVT avoid detection by immunocompetent hosts is of particular interest, given that these malignancies are rarely seen in other species in nature. Both of these transmissible cancers can downregulate the host immune system, enabling proliferation. DFTD is characterized by epigenetic modifications to the DNA promoter regions of ß2microglobulin, transporters associated with antigen processing 1 and 2, MHC I, and MHC II-crucial proteins required in the detection and surveillance of foreign material. Downregulation during DFTD may be achieved by altering the activity of histone deacetylases. DFTD has caused widespread destruction of devil populations, placing the species on the brink of extinction. CTVT demonstrates a proliferative phase, during which the tumor evades immune detection, allowing it to proliferate, and a regressive phase when hosts mount an effective immune response. Alteration of TGFß signaling in CTVT likely impedes the antigen-processing capabilities of canine hosts in addition to hindering the ability of natural killer cells to detect immune system downregulation. Immunosuppressive cytokines such as CXCL7 may contribute to a favorable microenvironment that supports the proliferation of CTVT. When viewed from an evolutionary paradigm, both DFTD and CTVT may conform to a model of host-parasite coevolution. Furthermore, various genetic features, such as genetically active transposons in CTVT and chromosomal rearrangements in DFTD, play important roles in promoting the survival of these disease agents. Understanding the mode of transmission for these transmissible cancers may shed light on mechanisms for human malignancies and reveal opportunities for treatment in the future.