9 Surprising Pieces Of Information About 3-Methyladenine

Finally, the shear modulus �� (i.e., stiffness) was derived at each location using the equation: ��=��c2��=��c2 where c is the shear velocity and �� is the volumic mass of the tissue. A time-of-flight algorithm described in a previous study ( 13) was used to derive a complete stiffness map in the region reached by the shear wave. Forty stiffness measurements were repeated at high rate over 2 cardiac cycles to investigate myocardial stiffness dynamics. Each stiffness measurement was achieved within 5 ms and was repeated every 7.5 ms (acquisition repetition frequency of 133 Hz). The ventricular pressure was recorded at the same time on an external analog to digital board (Usbamp, g.tec Medical Engineering GmbH, Schiedlberg, Austria), allowing synchronization of the acquisition in post-treatment. SWI was performed in Langendorff perfused isolated adult rat hearts (heart/body weight ratio 3.7 �� 0.3 mg/g, n = 6). The isolated hearts were immersed into a saline 3-Methyladenine concentration bath (50 �� 50 �� 50 mm3), and the ultrasonic array was positioned through an acoustic window performed on the side of the water tank (Online Appendix). In all experiments, the probe orientation was long-axis view unless specified. The distance between Oxymatrine the array and the heart was approximately 5 mm. All experiments were carried out according to the European Community guiding principles in the care and use of animals (86/609/CEE). Ex vivo physiology experiments were performed in Langendorff perfused isolated rat hearts (n = 6) according to previously described methods (17). (Please see the supplemental methods section in the Online Appendix.) Pre-load was modified by varying balloon volume by 5-��l increments. Contractility was modified by changing Krebs extracellular calcium concentrations or by infusing increasing concentrations of isoproterenol. Changes in myocardial stiffness were analyzed using a paired 2-tailed t test to evaluate PD0325901 molecular weight the significance of the difference between individual mean values under different inotropic effects or pre-load conditions. Linear regression was used for correlation between systolic stiffness and contractility. Statistical significance was inferred for p