Eighty patients underwent open-heart surgery from March 1990 to March 1993. We used combined aortic root (antegrade)/coronary sinus (retrograde) perfusion for cardioplegia delivery as a means of ...myocardial protection. The special retroplegia cannula was introduced to the coronary sinus (CS) in 67 patients by the transatrial (blind intubation) after one cannula cava insertion; the CS was cannulated under direct vision by right atriotomy after bicaval cannulation in 13 patients. Varied and prolonged cardiac procedures were done using cooled crystalloid cardioplegia (4 centigrades + potassium) except in one patient with severe ventricular damage in whom warm blood cardioplegia was infused. There was no CS or cardiac vein damage or disruption. There was no A-V blockade. The CS was intubated easily in all cases and cardioplegia solution readily infused. Coronary sinus pressure never exceeded 40 mm Hg. Overall hospital mortality (30 days postoperative) was 3.75% (3 cases). Sepsis was the cause of death in 2 patients and stroke in one. Inotropes were used in few cases as a means of renal protection. We conclude that the combined antegrade/retrograde cardioplegia delivery can be used routinely in most patients undergoing open-heart surgery.
Modeling, control and implementation of a real redundant robot with five Degrees Freedom (DOF) of the SCARA (Selective Compliant Assembly Robot Arm) manipulator type is presented. Through geometric ...methods and structural and functional considerations, the inverse kinematics for redundant robot can be obtained. By means of a modification of the classical sliding mode control law through a hyperbolic function, we get a new algorithm which enables reducing the chattering effect of the real actuators, which together with the learning and adaptive controllers, is applied to the model and to the real robot. A simulation environment including the actuator dynamics is elaborated. A 5 DOF robot, a communication interface and a signal conditioning circuit are designed and implemented for feedback. Three control laws are executed in: a simulation structure (together with the dynamic model of the SCARA type redundant manipulator and the actuator dynamics) and a real redundant manipulator of the SCARA type carried out using MatLab/Simulink programming tools. The results, obtained through simulation and implementation, were represented by comparative curves and RMS indices of the joint errors, and they showed that the redundant manipulator, both in the simulation and the implementation, followed the test trajectory with less pronounced maximum errors using the adaptive controller than the other controllers, with more homogeneous motions of the manipulator.
The clinical profile of belatacept in kidney transplant recipients was evaluated to determine if earlier results in the BENEFIT study were sustained at 3 years. BENEFIT is a randomized 3 year, phase ...III study in adults receiving a kidney transplant from a living or standard criteria deceased donor. Patients were randomized to a more (MI) or less intensive (LI) regimen of belatacept, or cyclosporine. 471/666 patients completed ≥3 years of therapy. A total of 92% (MI), 92% (LI), and 89% (cyclosporine) of patients survived with a functioning graft. The mean calculated GFR (cGFR) was ∼21 mL/min/1.73 m2 higher in the belatacept groups versus cyclosporine at year 3. From month 3 to month 36, the mean cGFR increased in the belatacept groups by +1.0 mL/min/1.73 m2/year (MI) and +1.2 mL/min/1.73 m2/year (LI) versus a decline of −2.0 mL/min/1.73 m2/year (cyclosporine). One cyclosporine‐treated patient experienced acute rejection between year 2 and year 3. There were no new safety signals and no new posttransplant lymphoproliferative disorder (PTLD) cases after month 18. Belatacept‐treated patients maintained a high rate of patient and graft survival that was comparable to cyclosporine‐treated patients, despite an early increased occurrence of acute rejection and PTLD.
Three‐year results from the BENEFIT study confirm the durability of the renal function benefits of belatacept over time compared to cyclosporine, balancing the early risks (acute rejection, posttransplant lymphoproliferative disorder) associated with belatacept.
The nonlinear behavior and the high performance requirement are the main problems that appear in the design of manipulator robots and their controllers. For that reason, the simulation, real-time ...execution and comparison of the performance of controllers applied to a robot with three degrees of freedom are presented. Five controllers are prepared to test the robot's dynamic model: predictive; hyperbolic sine-cosine; sliding mode; hybrid composed of a predictive + hyperbolic sine-cosine controller; and adaptive controller. A redundant robot, a communication and signal conditioning interface, and a simulator are developed by means of the MatLab/Simulink software, which allows analyzing the dynamic performance of the robot and of the designed controllers. The manipulator robot is made to follow a test trajectory which, thanks to the proposed controllers, it can do. The results of the performance of this manipulator and of its controllers, for each of the three joints, are compared by means of RMS indices, considering joint errors according to the imposed trajectory and to the controller used.
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