SummaryWithin the medial frontal cortex, the supplementary eye field (SEF), supplementary motor area (SMA), and pre-SMA have been implicated in the control of voluntary action, especially during motor sequences or tasks involving rapid choices between competing response plans. However, the precise roles of these areas remain controversial. Here, we study two extremely rare patients with microlesions of the SEF and SMA to demonstrate that these areas are critically involved in unconscious and involuntary motor control. We employed masked-prime stimuli that evoked automatic inhibition in healthy people and control patients with lateral premotor or pre-SMA damage. In contrast, our SEF/SMA patients showed a complete reversal of the normal inhibitory effect—ocular or manual—corresponding to the functional subregion lesioned. These findings imply that the SEF and SMA mediate automatic effector-specific suppression of motor plans. This automatic mechanism may contribute to the participation of these areas in the voluntary control of action.

Objective Although hypertension is the most common risk factor for thoracic aortic diseases, it is not understood how increased pressures on the ascending aorta lead to aortic aneurysms. We investigated the role of Ang II type 1 (AT1) receptor activation in ascending aortic remodeling in response to increased biomechanical forces using a transverse aortic constriction (TAC) mouse model. Approach and Results Two weeks after TAC, the increased biomechanical pressures led to ascending aortic dilatation, aortic wall thickening and medial hypertrophy. Significant adventitial hyperplasia and inflammatory responses in TAC ascending aortas were accompanied by increased adventitial collagen, elevated inflammatory and proliferative markers, and increased cell density due to accumulation of myofibroblasts and macrophages. Treatment with losartan significantly blocked TAC induced vascular inflammation and macrophage accumulation. However, losartan only partially prevented TAC induced adventitial hyperplasia, collagen accumulation and ascending aortic dilatation. Increased Tgfb2 expression and phosphorylated-Smad2 staining in the medial layer of TAC ascending aortas was effectively blocked with losartan. In contrast, the increased Tgfb1 expression and adventitial phospho-Smad2 staining were only partially attenuated by losartan. In addition, losartan significantly blocked Erk activation and ROS production in the TAC ascending aorta. Conclusions Inhibition of the AT1 receptor using losartan significantly attenuated the vascular remodeling associated with TAC but did not completely block the increased TGF- β1 expression, adventitial Smad2 signaling and collagen accumulation. These results help to delineate the aortic TGF-β signaling that is dependent and independent of the AT1 receptor after TAC.

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Rationale Mutations in ACTA2, encoding the smooth muscle isoform of α-actin (SM α-actin), cause thoracic aortic aneurysms, acute aortic dissections, and occlusive vascular diseases. Objective We sought to identify the mechanism by which loss of SM α-actin causes aortic disease. Methods and Results Acta2−/− mice have an increased number of elastic lamellae in the ascending aorta and progressive aortic root dilation as assessed by echocardiography that can be attenuated by treatment with losartan, an angiotensin II (AngII) type 1 receptor blocker. AngII levels are not increased in Acta2−/− aortas or kidneys. Aortic tissue and explanted smooth muscle cells (SMCs) from Acta2−/− aortas show increased production of reactive oxygen radicals (ROS) and increased basal NF-κB signaling, leading to an increase in the expression of the AngII receptor type I (Agtr1a) and activation of signaling at 100-fold lower levels of AngII in the mutant compared to wild-type cells. Furthermore, disruption of SM α-actin filaments in wildtype SMCs by various mechanisms activates NF-κB signaling and increases expression of Agtr1a. Conclusions These findings reveal that disruption of SM α-actin filaments in SMCs increases ROS levels, activates NF-κB signaling and increases Agtr1a expression, thus potentiating AngII signaling in vascular SMCs without an increase in the exogenous levels of AngII.

People spend an enormous amount of time searching for and saving information online. Existing tools capture only a small portion of the cognitive processing a user engages in while making sense of a new domain. In this paper we introduce a novel interface for capturing online information in a structured but lightweight way. We use this interface as a platform to experimentally characterize the costs and benefits of structuring information during the sensemaking process. Our results contribute empirical knowledge relevant to theories of information seeking and sensemaking, and practical implications for the development of tools to capture and share online information.