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PurposeThe phosphodiesterase inhibitor sildenafil is a promising treatment for neurodegenerative disease, but it can cause oxidative stress in photoreceptors ex vivo and degrade visual performance in humans. Here, we test the hypotheses that in wildtype mice sildenafil causes i) wide-spread photoreceptor oxidative stress in vivo that is linked with ii) impaired vision.MethodsIn dark or light-adapted C57BL/6 mice ± sildenafil treatment, the presence of oxidative stress was evaluated in retina laminae in vivo by QUEnch-assiSTed (QUEST) magnetic resonance imaging, in the subretinal space in vivo by QUEST optical coherence tomography, and in freshly excised retina by a dichlorofluorescein assay. Visual performance indices were also evaluated by QUEST optokinetic tracking.ResultsIn light-adapted mice, 1 hr post-sildenafil administration, oxidative stress was most evident in the superior peripheral outer retina on both in vivo and ex vivo examinations; little evidence was noted for central retina oxidative stress in vivo and ex vivo. In dark-adapted mice 1 hr after sildenafil, no evidence for outer retina oxidative stress was found in vivo. Evidence for sildenafil-induced central retina rod cGMP accumulation was suggested as a panretinally thinner, dark-like subretinal space thickness in light-adapted mice at 1 hr but not 5 hr post-sildenafil. Cone-based visual performance was impaired by 5 hr post-sildenafil and not corrected with anti-oxidants; vision was normal at 1 hr and 24 hr post-sildenafil.ConclusionsThe sildenafil-induced spatiotemporal pattern of oxidative stress in photoreceptors dominated by rods was unrelated to impairment of cone-based visual performance in wildtype mice.

A 75‐year‐old Black man presented for evaluation of a skin lesion on his right shoulder. The lesion had been present for 3 months and was bleeding. A physical exam demonstrated a 2.7 cm exophytic, crusted, blue‐to‐purple plaque. A shave biopsy was performed, and histopathological examination revealed anastomosing strands of basaloid cells in the dermis, leading to a diagnosis of fibroepithelioma of pinkus (FeP). FeP is a rare variant of basal cell carcinoma. It typically presents as a solitary, pink, pedunculated papule on the lower back, but the presentation can vary. This case contributes to the scarce literature on the occurrence of FeP in skin of color populations. Here, we raise the possibility that FeP may present differently in skin of color patients compared to white patients. Greater clinician awareness can foster improved identification, management, and understanding of FeP in diverse populations. [ABSTRACT FROM AUTHOR]

GLO:DIF/01jan21:ijd15113-fig-0001.jpg PHOTO (COLOR): 1 Hyperpigmented macules and papules on the bilateral chest gl GLO:DIF/01jan21:ijd15113-fig-0002.jpg PHOTO (COLOR): 2 Café au lait macule with superimposed hyperpigmented macules and papules on the left lower back gl After a robust review of the literature, we concluded that our patient's skin findings are most consistent with speckled lentiginous nevi, also called nevus spilus. It is thought that this is a subtype of congenital melanocytic nevus, but because these nevi are not always clinically obvious at birth, there is debate as to whether they are truly congenital or acquired.1 This condition presents as café au lait macules with superimposed melanocytic nevi. Patients with speckled lentiginous nevi, whether associated with a syndrome or not, are at increased risk for melanoma, so regular skin checks for any suspicious lesions are crucial.1 In addition, the nevi may progress with pregnancy or sun exposure, so patients should be aware that the appearance may change over time and new macules and papules may develop. [Extracted from the article]