This study was designed to determine whether adult mouse induced pluripotent stem cells (iPSCs), could be used to produce retinal precursors and subsequently photoreceptor cells for retinal transplantation to restore retinal function in degenerative hosts. iPSCs were generated using adult dsRed mouse dermal fibroblasts via retroviral induction of the transcription factors Oct4, Sox2, KLF4 and c-Myc. As with normal mouse ES cells, adult dsRed iPSCs expressed the pluripotency genes SSEA1, Oct4, Sox2, KLF4, c-Myc and Nanog. Following transplantation into the eye of immune-compromised retinal degenerative mice these cells proceeded to form teratomas containing tissue comprising all three germ layers. At 33 days post-differentiation a large proportion of the cells expressed the retinal progenitor cell marker Pax6 and went on to express the photoreceptor markers, CRX, recoverin, and rhodopsin. When tested using calcium imaging these cells were shown to exhibit characteristics of normal retinal physiology, responding to delivery of neurotransmitters. Following subretinal transplantation into degenerative hosts differentiated iPSCs took up residence in the retinal outer nuclear layer and gave rise to increased electro retinal function as determined by ERG and functional anatomy. As such, adult fibroblast-derived iPSCs provide a viable source for the production of retinal precursors to be used for transplantation and treatment of retinal degenerative disease.

Osteochondroma, the most common tumor of bone, is usually asymptomatic. Vascular complications are an atypical presentation and include true or false aneurysm formation, deep venous thrombosis, and arterial insufficiency. A review of the English literature identified 130 cases of osteochondroma-related vascular complications. We describe the case of a 38-year-old man presenting with left calf pain and swelling who was diagnosed with the rare constellation of a popliteal pseudoaneurysm and incidental peroneal vein thrombosis secondary to a fractured femoral sessile osteochondroma. This was treated with resection of the osteochondroma, excision of the aneurysm, and primary end-to-end anastomosis of the artery.

Brachial artery pseudoaneurysms (BAPs) are rare but could lead to complications of high morbidity. We report a case of a BAP presenting with hand ischemia and median nerve neuropathy nearly a decade after the inciting iatrogenic trauma, successfully treated with excision and direct repair. This report highlights that untreated pseudoaneurysms can be indolent and present late with both symptoms of embolization and local compression.