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A limb's initial position is often biased to the right of the midline during activities of daily living. Given this specific initial limb position, visual cues of the limb become first available to the ipsilateral eye relative to the contralateral eye. The current study investigated online control of the dominant limb as a function of having visual cues available to the ipsilateral or contralateral eye, in relation to the initial start position of the limb. Participants began each trial with their right limb on a home position to the left or right of the midline. After movement onset, a brief visual sample was provided to the ipsilateral or contralateral eye. On one third of the trials, an imperceptible 3 cm target jump was introduced. If visual information from the eye ipsilateral to the limb is preferentially used to control ongoing movements of the dominant limb, corrections for the target jump should be observed when movements began from the right of the body's midline and vision was available to the ipsilateral eye. As expected, limb trajectory corrections for the target jump were only observed when participants started from the right home position and visual information was provided to the ipsilateral eye. We purport that such visuomotor asymmetry specialization emerges via neurophysiological developments, which may arise from naturalistic and probabilistic limb trajectory asymmetries., Competing Interests: Declaration of Competing Interest The authors have no financial interest or benefit that may arise from the direct application of this research., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The authors investigated how visual information from the nondominant and dominant eyes are utilized to control ongoing dominant hand movements. Across 2 experiments, participants performed upper-limb pointing movements to a stationary target or an imperceptibly shifted target under monocular-dominant, monocular-nondominant, and binocular viewing conditions. Under monocular-dominant viewing conditions, participants exhibited better endpoint precision and accuracy. On target jump trials, participants spent more time after peak limb velocity and significantly altered their trajectories toward the new target location only when visual information from the dominant eye was available. Overall, the results suggest that the online visuomotor control processes that typically take place under binocular viewing conditions are significantly influenced by input from the dominant eye.

Objectives: We investigated whether oxidative stress and the arginine/nitric oxide pathway differ in control subjects and in adult patients who are candidates for the three most common cardiac surgical operations: coronary bypass surgery, aortic valve replacement for calcific non-rheumatic aortic stenosis or mitral valve repair for degenerative mitral insufficiency., Methods: In this prospective observational study, we studied 165 consecutive patients undergoing surgery from January to June 2011 (coronary bypass surgery, n = 63; aortic valve replacement for calcific non-rheumatic aortic stenosis, n = 51; mitral valve repair for degenerative mitral insufficiency, n = 51). Thirty-three healthy subjects with cardiovascular risk factors similar to surgery patients were also studied (Controls). Oxidative stress (the ratio of reduced and oxidized glutathione and urinary isoprostane), antioxidants (alpha- and gamma tocopherol) and factors involved in nitric oxide synthesis (arginine, symmetric and asymmetric dimethylarginine) were measured before surgery. Analysis of variance general linear models and principal component analysis were used for statistical analysis., Results: Surgical patients had increased levels of oxidative stress and decreased levels of antioxidants. Increased levels of nitric oxide inhibitor asymmetric dimethylarginine were detected in surgical candidates, suggesting arginine/nitric oxide pathway impairment. Concerning the differences among surgical procedures, higher oxidative stress and a major imbalance of the ratio between substrate and inhibitors of nitric oxide synthesis were evidenced in patients who were candidates for mitral valve repair with respect to coronary bypass surgery patients and patients with calcific non-rheumatic aortic stenosis., Conclusions: Patients undergoing cardiac surgery have increased oxidative stress and a trend towards an impaired arginine/nitric oxide pathway with respect to Controls. Patients affected by mitral valve regurgitation show more pronounced perturbations in these pathways. The clinical implications of these findings need to be investigated.

Use of the Doppler ultrasonic flowmeter to assess testicular perfusion has potentially precise application in the evaluation of acute scrotal swelling. Recent reports suggest an almost infallible degree of accuracy in differentiating testicular torsion, with reduced or absent blood flow, from inflammatory processes, with accompanying increased vascular perfusion. This report of 4 falsely negative Doppler examinations confirmed by surgical exploration warns against relying on this as a single test in the diagnosis of testicular torsion. Only thorough clinical assessment of each patient and exploration in doubtful cases will assure maximum testicular salvage.