Transient ischemic attack results in tolerance to a subsequent severe brain ischemic attack, which is known as brain ischemic tolerance (BIT). In other words, preconditioning intervention leads to ischemic tolerance. The preconditioning intervention methods include ischemia, oxidative stress, and drug resistance to oxidative phosphorylation. Because of safety considerations, these methods are o...

Ischaemic preconditioning was originally described in animal hearts as histological infarct-size limitation by a previous brief episode of ischaemia. In humans, ischaemic preconditioning has been demonstrated in several in vitro and in vivo models, including coronary artery bypass grafting and percutaneous transluminal coronary angiograplasty, using surrogate markers of ischaemia and reperfusio...

We propose a variant of variable preconditioning for Generalized Conjugate Residual (GCR)-like methods. The preconditioning is carried out by roughly solving Az = v by an iterative method to a certain degree of accuracy instead of computing Kz = v in a conventional preconditioned algorithm. In our proposal, the number of iterations required for computing Az = v is changed at each iteration by e...

Transient forebrain or global ischemia induces neuronal death in vulnerable CA1 pyramidal cells with many features. A brief period of ischemia, i.e., ischemic preconditioning, or a modified reperfusion such as ischemic postconditioning, can afford robust protection of CA1 neurons against ischemic challenge. Therefore, we investigated the effect of ischemic preconditioning and postconditioning o...

To clarify the question whether the duration of hypoxia exposure has an influence on the point in time or the strength of hypoxic preconditioning, hypoxia exposure of rats lasting 1 and 8 h was tested regarding the modification of susceptibility to acute pentylenetetrazol-induced seizures. Following the short-lasting (1 h) hypoxia, the maximum level of preconditioning action was observed 7 days...

Approximate Generalized Inverses with Iterative Refinement for $\epsilon$-Accurate Preconditioning of Singular Systems

Background. Infarct size reduction by ischemic preconditioning is believed to be mediated by adenosine; however, whether adenosine is the factor responsible for the initiation of this protection remains unknown. It is possible that during preconditioning, adenosine stimulates receptors on presynaptic nerve terminals and retards the release of norepinephrine (NE) during the prolonged ischemia or...

As the development of synthetic drugs for the prevention of stroke has proven challenging, utilization of natural products capable of preconditioning neuronal cells against ischemia-induced cell death would be a highly useful complementary approach. In this study using an oxygen-glucose deprivation and reoxygenation (OGD/R) model in PC12 cells, we show that 2-day pretreatment with green tea pol...

Single or multiple brief periods of ischemia (preconditioning) have been shown to protect the myocardium from infarction after a subsequent more prolonged ischemic insult. To test the hypothesis that preconditioning is the result of opening ATP-sensitive potassium (KATP) channels, a selective KATP channel antagonist, glibenclamide, was administered before or immediately after preconditioning in...

Iterative methods are often used for applications in science and engineering to solve very large scale linear systems. Efficiency of an iterative method depends on the amount of computation needed per iteration, as well as on the number of iterations needed to reconstruct the desired approximate solution. Convergence speed can be accelerated using a technique called preconditioning. Although pr...