This study evaluates the durability of a novel tissue engineered blood vessel (TEBV) created by seeding a natural vascular tissue scaffold (decellularized human saphenous vein allograft) with autologous adipose-derived stem cells (ASC) differentiated into endothelial-like cells. Previous work with this model revealed the graft to be thrombogenic, likely due to inadequate endothelial differentiation as evidenced by minimal production of nitric oxide (NO). To evaluate the importance of NO expression by the seeded cells, we created TEBV using autologous ASC transfected with the endothelial nitric oxide synthase (eNOS) gene to produce NO. We found that transfected ASC produced NO at levels similar to endothelial cell (EC) controls in vitro and capable of causing vasorelaxation of aortic specimens ex vivo. TEBV (n=5) created with NO-producing ASC and implanted as interposition grafts within the aorta of rabbits remained patent for two months and demonstrated a non-thrombogenic surface compared to unseeded controls (n=5). Despite the xenograft nature of the scaffold, TEBV structure remained well-preserved in seeded grafts. In sum, this study demonstrates that up-regulation of NO expression within adult stem cells differentiated towards an endothelial-like cell imparts a non-thrombogenic phenotype and highlights the importance of NO production by cells to be used as endothelial cell substitutes in vascular tissue engineering applications.

ASSeSSment mAtterSAS prACtitionerS, we are now regularly encouraged to incorporate assessment into our daily practice by asking what pat terenzini and m. lee upcraft described as the most important questions in student affairs: "is what we are doing having any effect, is that effect the intended one, and how do we know?" (p. 218). however, we are not always sure how to approach these questions, and frankly, we are often a bit afraid of the answers. despite the fact that assessment sometimes feels uncomfortable and cumbersome, even daunting, it is critical for student affairs educators to see the value of collecting evidence of student learning. So how might we answer these important questions in a time when they have become fundamental to our work? through three fictional composites, based roughly on actual events, this article examines the defining features of a faculty approach to understanding student learning and their contributions to that learning-namely, the scholarship of teaching and learning (Sotl).

nerve action potential (SNAP) amplitude, and nerve conduction velocity (NCV)). These results were correlated with peroneus muscle and peroneal nerve histology.Results: Baseline physiologic characteristics were similar between groups. Neuromuscular recovery in groups with early restoration of flow (Control, 1HR, 3HR) was similar and nearly complete (92%, 98% and 88% respectively; p Ͼ0.45). While recovery was diminished in both 6HR and Ligation; Ligation, rather than repair, exhibited greater recovery (68% vs 53%; p Ͻ0.05). These relationships correlated with the pathologic grade of degeneration, necrosis, and fibrosis (p Ͻ0.05). Using the PMR, the ischemic threshold of the extremity is reached at 5 hours.Conclusions: This study reports a novel and translatable animal model of extremity ischemia and reperfusion correlating ischemic time to functional markers of recovery. In this model an ischemic threshold of 5 hours is defined after which Ligation is associated with less irreversible injury than surgical restoration of flow.

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Background: Spontaneous dissection of the superior mesenteric artery (SMA) is rare. We report a case of rupture of the SMA after spontaneous dissection in a 51-year-old man who presented with acute onset of abdominal pain and hypotension. The patient was diagnosed as having segmental arterial mediolysis (SAM).Case: The patient was initially treated with intravenous fluid resuscitation and endovascular intervention, followed by open surgery. The relevant features of the case as well as SAM are presented. In addition, a review of all available published literature on SAM to date is presented. No identifiable cause for dissection was found. The patient was diagnosed as having SAM. He did well and was discharged home on postoperative day 8. A follow-up CT scan showed additional disease characteristic of SAM in a branch of the inferior mesenteric artery that was treated with coil embolization.Conclusions: SAM is a rare arteriopathy of unknown etiology. Differential diagnosis includes fibromuscular dysplasia and inflammatory arteritis such as polyarteritis nodosa. Differentiation is important, because there is no standard treatment for SAM.