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Cantú syndrome (CS), a multisystem disease with a complex cardiovascular phenotype, is caused by gain-of-function (GoF) variants in the Kir6.1/SUR2 subunits of ATP-sensitive potassium (KATP) channels and is characterized by low systemic vascular resistance, as well as tortuous, dilated, vessels, and decreased pulse-wave velocity. Thus, CS vascular dysfunction is multifactorial, with both hypomyotonic and hyperelastic components. To dissect whether such complexities arise cell autonomously within vascular smooth muscle cells (VSMCs) or as secondary responses to the pathophysiological milieu, we assessed electrical properties and gene expression in human induced pluripotent stem cell-derived VSMCs (hiPSC-VSMCs), differentiated from control and CS patient-derived hiPSCs, and in native mouse control and CS VSMCs. Whole-cell voltage clamp of isolated aortic and mesenteric arterial VSMCs isolated from wild-type (WT) and Kir6.1[V65M] (CS) mice revealed no clear differences in voltage-gated K+ (Kv) or Ca2+ currents. Kv and Ca2+ currents were also not different between validated hiPSC-VSMCs differentiated from control and CS patient-derived hiPSCs. While pinacidil-sensitive KATP currents in control hiPSC-VSMCs were similar to those in WT mouse VSMCs, they were considerably larger in CS hiPSC-VSMCs. Under current-clamp conditions, CS hiPSC-VSMCs were also hyperpolarized, consistent with increased basal K conductance and providing an explanation for decreased tone and decreased vascular resistance in CS. Increased compliance was observed in isolated CS mouse aortae and was associated with increased elastin mRNA expression. This was consistent with higher levels of elastin mRNA in CS hiPSC-VSMCs and suggesting that the hyperelastic component of CS vasculopathy is a cell-autonomous consequence of vascular KATP GoF. The results show that hiPSC-VSMCs reiterate expression of the same major ion currents as primary VSMCs, validating the use of these cells to study vascular disease. Results in hiPSC-VSMCs derived from CS patient cells suggest that both the hypomyotonic and hyperelastic components of CS vasculopathy are cell-autonomous phenomena driven by KATP overactivity within VSMCs ., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Physiological Society.)

Objectives: Skin changes in acromegaly are often the first sign of the disease. The aim of this study was to describe the cutaneous findings in patients with acromegaly. In addition, a secondary aim was to investigate the possible association of these findings with remission status and concomitant endocrinopathies., Design, Patients, and Measurements: In this prospective multicenter study, 278 patients over the age of 18 years with acromegaly who were followed up in 14 different tertiary healthcare institutions were included. These patients, who were followed up by the Endocrinology Department, were then referred to a dermatologist for dermatological examination. The frequency of skin lesions was investigated by detailed dermatologic examination. Dermatological diagnosis is reached by clinical, dermatological and/or dermoscopic examination, and rarely skin punch biopsy examinations in suspicious cases. The possible association of the skin findings between remitted and nonremitted patients and with concomitant endocrinopathies were evaluated., Results: The most common skin findings in patients with acromegaly in our study were skin tags (52.5%), cherry angiomas (47.4%), seborrhoea (37%), varicose veins (33%), acneiform lesions (28.8%), hyperhidrosis (26.9%) and hypertrichosis (18.3%). Hypertrichosis was significantly more prevalent in patients nonremitted (p: .001), while xerosis cutis was significantly more prevalent in patients remitted (p: .001). The frequency of diabetes mellitus and hypothyroidism was significantly higher in patients with varicose veins and seborrhoeic keratosis than those without. Additionally, the coexistence of hypothyroidism, hyperthyroidism and galactorrhea was significantly higher in patients with Cherry angioma than in those without Cherry angioma (p-values: .024, .034 and .027, respectively). The frequency of hypogonadism in those with xerosis cutis was significantly higher than in those without (p: .035)., Conclusions: Cutaneous androgenization findings such as skin tag, seborrhoea, acne and acanthosis nigricans are common in patients with acromegaly. Clinicians should be aware that skin findings associated with insulin resistance may develop in these patients. It can be said that the remission state in acromegaly has no curative effect on cutaneous findings. Only patients in remission were less likely to have hypertrichosis. This may allow earlier review of the follow-up and treatment of acromegaly patients presenting with complaints of hypertrichosis. Additionally, it can be said that patients with skin findings such as cherry angioma may be predisposed to a second endocrinopathy, especially hypothyroidism. Including dermatology in a multidisciplinary perspective in acromegaly patient management would be beneficial to detect cutaneous findings earlier., (© 2024 John Wiley & Sons Ltd.)

H syndrome is a rare autosomal recessive genodermatosis that falls under the histiocytosis-lymphadenopathy plus syndrome. The term "H syndrome" includes manifestations such as hyperpigmentation, hypertrichosis, hepatosplenomegaly, heart anomalies, hearing loss, hypogonadism, low height, and occasionally hyperglycemia. The syndrome is associated with mutations in the SLC29A3 gene, which encodes the human equilibrative transporter 3 present in endosomes, lysosomes, and mitochondria. The generalized and ubiquitous presence of affected lysosomes and mitochondria contributes to the systemic and phenotypically heterogeneous manifestations of the syndrome. H syndrome manifestations are cutaneous, systemic, and organ-specific. The pathognomonic signs are hypertrichosis and hyperpigmentation in the inner thighs and shins. However, not all patients present with these symptoms. H syndrome management involves a multidisciplinary approach to address specific symptoms and complications. The prognosis of H syndrome depends on several factors, including the extent and severity of clinical manifestations, the presence of complications, and timely diagnosis and management. Further studies are needed to explore the association between prognosis and the different mutations encountered in H syndrome., (Copyright © 2024 Hematology/Oncology and Stem Cell Therapy.)

Diffuse neurofibroma is a rare type of neurofibroma uncommonly reported in infancy. It is a slow growing tumor originating in the peripheral nerve sheath. We present the case of a 17-month-old boy with diffuse neurofibroma of the scalp associated with hypertrichosis. His genetic and clinical workup for neurofibromatosis was negative., (© 2024 The Authors. Pediatric Dermatology published by Wiley Periodicals LLC.)