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Rationale: Vascular endothelial growth factor (VEGF), a major proangiogenic agent, exerts its proangiogenic action by binding to VEGF receptor 2 (VEGFR2), the activity of which is regulated by direct interactions with other cell surface proteins, including integrin ␣ V ␤ 3 . However, how the interaction between VEGFR2 and integrin ␣ V ␤ 3 is regulated is not clear. Objective:To investigate whether Necl-5/poliovirus receptor, an immunoglobulin-like molecule that is known to bind integrin ␣ V ␤ 3 , regulates the interaction between VEGFR2 and integrin ␣ V ␤ 3 , and to clarify the role of Necl-5 in the VEGF-induced angiogenesis. Key Words: cell adhesion molecules Ⅲ angiogenesis Ⅲ peripheral vascular disease A ngiogenesis plays an important role in diverse developmental, physiological, and pathological processes. Angiogenesis is triggered by the interaction of proangiogenic growth factors and extracellular matrix with their receptors. Vascular endothelial growth factor (VEGF) is a major proangiogenic agent that regulates multiple key steps of angiogenesis. VEGF exerts its proangiogenic action by binding to VEGF receptor 2 (VEGFR2). The activity of VEGFR2 is regulated by direct interactions with other cell surface proteins, such as coreceptor neuropilins 1 and adhesion molecules, including VE-cadherin 2 and integrins. 3 Integrins, including integrin ␣ V ␤ 3 , are critically involved in angiogenesis and initiate signals that control cell migration, proliferation, and survival. 4 Receptors such as VEGFR2 and plateletderived growth factor (PDGF) receptor (PDGFR) interact with integrins, and these interactions exhibit synergistic effects and cooperatively regulate diverse intracellular signals that control key cell functions. 3,5,6 However, how the interaction between VEGFR2 and integrin ␣ V ␤ 3 through their extracellular regions is regulated is not known. Methods and Results:Original received September 15, 2011; revision received January 12, 2012; accepted January 18, 2012. In December 2011 Nectins and nectin-like molecules (Necls) are immunoglobulinlike cell adhesion molecules that are essential for the formation of cell-cell adhesions, and these molecules regulate a variety of cellular functions, including cell polarization, differentiation, movement, proliferation, and survival. 7,8 Necls comprise a family with 5 members, Necl-1 to -5, and among these, Necl-5 exhibits distinctive expression profiles. Necl-5 was originally identified as human poliovirus receptor (PVR), also termed CD155, 9,10 and as rodent Tage4, which is overexpressed in rodent colon carcinoma. 11,12 Necl-5 is expressed ubiquitously, but its expression level is extremely low in most adult organs in rodents. 13,14 However, it becomes upregulated in the developing or regenerating liver 15,16 and transformed cells. 17,18 In NIH3T3 cells, Necl-5 forms a complex with integrin ␣ V ␤ 3 and PDGFR, and the formation of this complex enhances cell movement and proliferation. 19 However, the function of Necl-5 and its mode of action in vascular endothelial ...

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An optimal image intensifier angulation used for obtaining an en face view of a target structure is important in electrophysiologic procedures performed around each coronary aortic sinus (CAS). However, few studies have revealed the fluoroscopic anatomy of the target area. This study investigated the optimal angulation for each CAS and the interventricular septum (IVS). The study included 102 consecutive patients who underwent computed tomography coronary angiography. The optimal angle for each CAS was determined by rotating the volume-rendered image around the vertical axis. The angle formed between the anteroposterior axis and IVS was measured using the horizontal section. The frontal direction was defined as zero, positive, or negative if the en face view of the target CAS was obtained in the frontal view, left anterior oblique (LAO) direction, or right anterior oblique (RAO) direction, respectively. The optimal angles for the left, right, and non-CASs were 120.3 ± 10.5°, 4.8 ± 16.3°, and -110.0 ± 13.8°, respectively. The IVS angle was 42.6 ± 8.5°. Accordingly, the optimal image intensifier angulations for the left, right, and non-CASs and the IVS were estimated to be RAO 60°, LAO 5°, LAO 70°, and RAO 50°, respectively. The IVS angle was the most common independent predictor of the optimal angle for each CAS. Differences in the optimal angulations for each CAS and the IVS are demonstrated. The biplane angulation needs to be tailored according to the individual patients and target structures for electrophysiologic procedures.