Vitiligo is a chronic skin condition caused by an autoimmune response that results in the progressive loss of melanocytes and recent studies have suggested that Janus kinase inhibitors (JAKi) are emerging as a promising new treatment modality. Therefore, to assess and understand the extent of knowledge in the emerging field of JAKi use in vitiligo, a scoping review of the literature was undertaken. The reviewed articles explored a wide variety of JAKi administered either orally or topically for vitiligo. There were no injectable JAKi studied. Tofacitinib was the most commonly studied oral JAKi in 16 of the 35 studies selected for review, followed by baricitinib (n = 3), and one study each with ritlecitinib, ruxolitinib, and upadacitinib. Ruxolitinib (n = 6) and tofacitinib (n = 6) were the most often studied topical JAKi, followed by delgocitinib (n = 1). Potential benefits may vary between JAKi based on their receptor selectivity profile and coexistent autoimmune diseases. A topical JAKi would be advantageous in limited body area involvement and in adolescents. Concurrent use of JAKi with phototherapy or sun exposure appears beneficial. Most studies permitted the use of other topical agents. Acne-related events, though frequent yet mild, were reported with both oral and topical JAKi. Nasopharyngitis, upper respiratory tract infections, and headaches were the most common adverse effects seen in the larger trials with JAKi. No serious or clinically meaningful hematology or thromboembolic events were detected. Treatment of vitiligo with oral or topical JAKi seems to be promising and the growing evidence shows a favorable risk-benefit profile.

UNASSIGNED: Leptomeningeal melanocytomas are rare tumours originating from neural crest derived melanocytes. They are usually solitary and presentation with multifocal meningeal melanocytoma is very rare and indicative of potentially more aggressive behaviour. This case report and scoping review sought to evaluate the presentation, and key radiological features that can help differentiate multifocal meningeal melanocytoma from other differentials and provide a discussion of the key management and prognostic points once these tumours are diagnosed.
UNASSIGNED: A 26 year old male presented with neck pain radiating to both shoulders and subjective weakness in left shoulder movement. MRI demonstrated a large enhancing C2-C3 intradural-extramedullary lesion with further lesions at the T7/T8 level, left cerebellopontine angle and midline suprachiasmatic region. Whilst the imaging appearances were initially thought be indicative of a phacomatosis such as NF2-related schwannomatosis, surgical excision of the cervical tumour confirmed a melanocytic tumour of leptomeningeal origin, consistent with multifocal meningeal melanocytoma. Patient made a good post-operative recovery and remains under half yearly radiological surveillance, with repeat MRI 6 months after surgery demonstrating subtle growth of the untreated intracranial and spinal lesions.
UNASSIGNED: This is the first description, to our knowledge, of a multifocal meningeal melanocytoma associated with both cerebellopontine angle and suprasellar lesions. This case and included scoping review highlight the need to consider this rare diagnosis whenever multifocal craniospinal lesions are encountered, and the need to consider aggressive management through surgical resection and adjuvant craniospinal radiotherapy once these tumours are diagnosed.

BACKGROUND: Treatment of vitiligo seeks to achieve three goals: cessation of disease progression, regeneration of pigmentation, and prevention of recurrence.
CONCLUSIONS: Number of nonsurgical interventions are available that suppress the autoimmune response and regenerate the melanocytes from the reservoir: phototherapy including psoralen and ultraviolet A, narrowband ultraviolet B, and 308-nm excimer and 311-nm Titanium:Sapphire lasers; topical agents including topical calcineurin inhibitors, topical corticosteroids, and topical 5-fluorouracil; and systemic agents including corticosteorids, mycophenolate mofetil, cyclosporine, methotrexate, minocycline, afamelanotide, and antioxidants. In recent years, a great advance has been made in the understanding of pathogenesis of vitiligo, and JAK inhibitors are being investigated as a new treatment. Minimally invasive procedures such as fractional lasers or microneedling can help achieve the optimal treatment outcome when used properly.
CONCLUSIONS: Our review describes various treatment modalities for vitiligo based on their molecular mechanism of action. Bridging the gap between molecular mechanisms and therapeutic options would be a valuable reference for physicians in clinical practice.

Since human skin is the primary interface responding to external mechanical stimuli, extrinsic forces can disrupt its balanced microenvironment and lead to cutaneous lesions. We performed this review to delve into the pathological effects of mechanical pressure on skin from the cellular perspective. Fibroblasts of different subsets act as heterogeneous responders to mechanical load and express diverse functionalities. Keratinocytes relay mechanical signals through mechanosensitive receptors and the ensuing neurochemical cascades to work collaboratively with other cells and molecules in response to pressure. Mast cells release cytokines and neuropeptides, promoting inflammation and facilitating interaction with sensory neurons, while melanocytes can be regulated by pressure through cellular and molecular crosstalk. Adipocytes and stem cells sense pressure to fine-tune their regulations of mechanical homeostasis and cell differentiation. Applying mechanical pressure to the skin can induce various changes in its microenvironment that potentially lead to pathological alterations, such as ischemia, chronic inflammation, proliferation, regeneration, degeneration, necrosis, and impaired differentiation. The heterogeneity of each cellular lineage and subset from different individuals with various underlying skin conditions must be taken into consideration when discussing the pathological effects of pressure on the skin. Thus, elucidating the mechanotransduction and mechanoresponsive pathways from the cellular viewpoint is crucial in diagnosing and managing relevant dermatological disorders.

Vitiligo is a disorder characterized by loss of epidermal melanocytes, resulting in depigmented macules and patches. While the relationship between ocular pathology and vitiligo has been demonstrated in conditions such as Vogt-Koyanagi-Harada and Alezzandrini syndromes, the ocular associations of non-syndromic vitiligo are incompletely understood. We conducted a systematic review to comprehensively describe the structural and functional changes seen in the eyes of patients with vitiligo, to identify patients at heightened risk for ocular disease, and to provide an approach to management of ocular manifestations of vitiligo. Overall, the strongest link between vitiligo and ocular pathology seems to lie with dry eye disease and pigmentary abnormalities of various ocular structures, especially the retinal pigment epithelium. Normal-tension glaucoma may also be more prevalent in the vitiligo population. The available literature did not provide conclusive evidence for increased risk of cataracts or uveitis. Aside from the impact of symptomatic dry eye disease, it seems unlikely that there are significant functional consequences of these ocular manifestations such as impaired visual acuity or visual fields.

Dermal melanocytosis includes several benign pigmented lesions which present as blue-gray color which is a result of the color transmission of melanin pigment through the dermis. While some types are present at birth, there is an acquired variant, acquired dermal melanocytosis (ADM), which usually involves faces of middle-aged Asian women. To the best of our knowledge, there are limited reports of extra facial ADM which all are on the trunk and extremities. Herein, we report a unique case of extra facial ADM affecting the scalp of a middle-aged man and provide a review of all extra facial ADM cases that have been reported.

Intraoral melanoacanthoma is a rare, reactive pigmented lesion that is mostly seen in black individuals with a tendency to occur more frequently in younger females. The color of melanoacanthoma may vary from brown to black, and it is commonly seen as a solitary lesion in the buccal mucosa. This lesion requires no treatment, and no malignant potential has been observed to date. The clinical presentation of multifocal oral melanoacanthoma (MOMA) (the rate of growth and the recurrence) is usually diagnostic. On the other hand, solitary oral melanoacanthoma might be difficult to diagnose, and a biopsy should be performed and examined by a well-trained oral pathologist. Here, we report two cases of MOMA with an unusual location in one case.

The neural crest (NC) is a multipotent cell population in vertebrate embryos with extraordinary migratory capacity. The NC is crucial for vertebrate development and forms a myriad of cell derivatives throughout the body, including pigment cells, neuronal cells of the peripheral nervous system, cardiomyocytes and skeletogenic cells in craniofacial tissue. NC induction occurs at the end of gastrulation when the multipotent population of NC progenitors emerges in the ectodermal germ layer in the neural plate border region. In the process of NC fate specification, fate-specific markers are expressed in multipotent progenitors, which subsequently adopt a specific fate. Thus, NC cells delaminate from the neural plate border and migrate extensively throughout the embryo until they differentiate into various cell derivatives. Multiple signalling pathways regulate the processes of NC induction and specification. This review explores the ongoing role of the Wnt/β-catenin signalling pathway during NC development, focusing on research undertaken in the Teleost model organism, zebrafish (Danio rerio). We discuss the function of the Wnt/β-catenin signalling pathway in inducing the NC within the neural plate border and the specification of melanocytes from the NC. The current understanding of NC development suggests a continual role of Wnt/β-catenin signalling in activating and maintaining the gene regulatory network during NC induction and pigment cell specification. We relate this to emerging models and hypotheses on NC fate restriction. Finally, we highlight the ongoing challenges facing NC research, current gaps in knowledge, and this field\'s potential future directions.

Our understanding of canine coat colour genetics and the associated health implications is developing rapidly. To date, there are 15 genes with known roles in canine coat colour phenotypes. Many coat phenotypes result from complex and/or epistatic genetic interactions among variants within and between loci, some of which remain unidentified. Some genes involved in canine pigmentation have been linked to aural, visual and neurological impairments. Consequently, coat pigmentation in the domestic dog retains considerable ethical and economic interest. In this paper we discuss coat colour phenotypes in the domestic dog, the genes and variants responsible for these phenotypes and any proven coat colour-associated health effects.

Vitiligo is a chronic inflammatory skin disease leading to the loss of epidermal melanocytes. To date, treatment options for vitiligo patients are limited, lack sustained efficacy, and are mainly based on off-label use of immunosuppressive agents, such as systemic or topical steroids or topical calcineurin inhibitors, in association with the use of ultraviolet light. However, recent insights into the understanding of the immune pathogenesis of the disease have led to the identification of several therapeutic targets and the development of targeted therapies that are now being tested in clinical trials. In this review, based on the physiopathology of the disease, we summarize emerging targets that could be developed for the treatment of vitiligo and discuss recent and ongoing developments of drugs for the management of the disease.