• Two hours after the last dose, serum lipid levels were determined and then the rats were subjected to 60 min of middle cerebral artery occlusion followed by 24 h of reperfusion. (nih.gov)
  • Although pretreatment with RHE plays an important role in the generation of tolerance against cerebral I/R injury, further studies are needed to clarify the mechanism of the ischemic tolerance. (nih.gov)
  • Neonates exposed to hypoxia-ischemia (HI) injury can have poor neurological and behavioral outcomes including cerebral palsy (CP) and incidences of learning deficits and disabilities due to the diffuse nature of the insults. (frontiersin.org)
  • Global cerebral ischemia followed by reperfusion, which leads to extensive neuronal damage, particularly the neurons in the hippocampal CA1 region. (springer.com)
  • Apoptosis is one of the major mechanisms that lead to neuronal death after cerebral ischemia and reperfusion. (springer.com)
  • The neuroprotective effects of remifentanil preconditioning against cerebral ischemia/reperfusion injury have been recently reported. (springer.com)
  • Here we investigated whether remifentanil postconditioning exerts neuroprotective effects against global cerebral ischemia/reperfusion injury in rats and its potential mechanisms. (springer.com)
  • Global cerebral ischemia was performed via 10 min of four-vessel occlusion. (springer.com)
  • We found remifentanil postconditioning markedly improved the spatial learning and memory as well as attenuated neuronal apoptosis in hippocampus caused by cerebral ischemia/reperfusion injury. (springer.com)
  • The results suggest that remifentanil postconditioning exhibits neuroprotective effects against global cerebral ischemia/reperfusion injury in rats, and its mechanisms might involve inhibition of neuronal apoptosis through the PI3K pathway. (springer.com)
  • Liang HW, Qiu SF, Shen J et al (2008) Genistein attenuates oxidative stress and neuronal damage following transient global cerebral ischemia in rat hippocampus. (springer.com)
  • Wang JY, Shen J, Gao Q et al (2008) Ischemic postconditioning protects against global cerebral ischemia/reperfusion-induced injury in rats. (springer.com)
  • Jeong S, Kim SJ, Jeong C et al (2012) Neuroprotective effects of remifentanil against transient focal cerebral ischemia in rats. (springer.com)
  • Ischaemic reperfusion injury (IRI) after tourniquet release during total knee arthroplasty (TKR) is related to postoperative cerebral complications. (medsci.org)
  • In an in vitro model of cerebral ischemia (oxygen glucose deprivation, OGD) we investigated whether erythropoietin (EPO) plays a critical role in ischemic preconditioning. (jneurosci.org)
  • This article describes the pathophysiology of, and treatment strategy for, cerebral ischemia. (nih.gov)
  • Reperfusion plays an important role in the pathophysiology of cerebral ischemia. (nih.gov)
  • Magnetic resonance imaging (MRI) and histological studies in rat focal ischemia models using transient middle cerebral artery (MCA) occlusion indicate that reperfusion after an ischemic episode of 2- to 3-hour duration does not result in reduction of the size of the infarct. (nih.gov)
  • Miller, A. A. , Dusting, G. J. , Roulston, C. L. and Sobey, C. G. (2006) NADPH-oxidase activity is elevated in penumbral and non-ischemic cerebral arteries following stroke. (gla.ac.uk)
  • Reactive oxygen species play a role in neuronal damage following cerebral ischemia-reperfusion. (gla.ac.uk)
  • We tested whether activity of the superoxide-generating enzyme, NADPH-oxidase, is enhanced in cerebral arteries within, adjacent and distant from the ischemic core. (gla.ac.uk)
  • Thus, the activity of NADPH-oxidase is enhanced in cerebral arteries from the ischemic penumbra at 24 h and 72 h following cerebral ischemia. (gla.ac.uk)
  • Additionally, NADPH-oxidase activity is temporarily enhanced after cerebral ischemia within arteries from non-ischemic parts of the brain. (gla.ac.uk)
  • Cerebral hyperexcitability in migraine experiencers might sensitize brain tissue to ischemia. (medscape.com)
  • [ 1 ] A recent hypothesis to explain the migraine-stroke association, based on experimental data obtained in mice expressing familial hemiplegic migraine type 1 mutations, is that the cerebral hyperexcitability phenotype associated with migraine might sensitize brain tissue to ischemia. (medscape.com)
  • Along with the observation that migraine mutants had an elevated minimum cerebral blood flow threshold required for tissue survival and developed larger infarcts, these findings directly support the hypothesis that brain tissue in migraineurs is more susceptible to ischemic injury. (medscape.com)
  • Based on these premises, taking advantage of the reliability of computed tomography perfusion (CTP) imaging in the estimation of cerebral tissue viability in both clinical and research settings, [ 4 ] we conducted a case-control study comparing CTP maps of migraineurs and nonmigraineurs patients with acute ischemic stroke aimed at investigating whether a personal history of migraine is associated with vulnerability to brain ischemia. (medscape.com)
  • Previous studies of global brain hypoxia ischemia have primarily focused on injury to the cerebral cortex and to the hippocampus. (cdc.gov)
  • The objective of this study was to determine whether homing of endothelial progenitor cells (EPCs) induced by ischemic preconditioning (IPC) contributed to the protection of renal acute ischemia-reperfusion injury (IRI) in male rats. (annalsoftransplantation.com)
  • Intermittent ischemia but not ischemic preconditioning is effective in restoring bile flow after ischemia reperfusion injury in the livers of aged rats. (edu.au)
  • In the present work, a hypoxia/reoxygenation (H/R) model in NRK-52E cells and ischemia-reperfusion model in rats were used. (mdpi.com)
  • To provide in vivo evidence that DJ‑1 is involved in the delayed cardioprotection induced by ischemic preconditioning (IPC) against oxidative stress caused by ischemia/reperfusion (I/R), the present study subjected male Sprague‑Dawley rats to IPC (3 cycles of 5‑min coronary occlusion/5‑min reperfusion) 24 h prior to I/R (30‑min coronary occlusion/120‑min reperfusion). (spandidos-publications.com)
  • Ren C, Yan Z, Wei D et al (2009) Limb remote ischemic postconditioning protects against focal ischemia in rats. (springer.com)
  • Ding ZM, Wu B, Zhang WQ et al (2012) Neuroprotective Effects of Ischemic Preconditioning and Postconditioning on Global Brain Ischemia in Rats through the same effect on inhibition of apoptosis. (springer.com)
  • Chen TY, Goyagi T, Toung TJ et al (2004) Prolonged opportunity for ischemic neuroprotection with selective kappa-opioid receptor agonist in rats. (springer.com)
  • Zhang Y, Chen ZW, Girwin M et al (2005) Remifentanil mimics cardioprotective effect of ischemic preconditioning via protein kinase C activation in open chest of rats. (springer.com)
  • However, at both time points after stroke, superoxide production by arteries from the ischemic penumbra was 8-fold greater than levels generated by arteries from control rats. (gla.ac.uk)
  • We therefore investigated the impact of global brain hypoxia-ischemia on the thalamic circuit function in the somatosensory system of young rats. (cdc.gov)
  • This coupled comorbidity of pathological ischemia and therapeutic reinjury of infarcted myocardium, namely, myocardial ischemia-reperfusion injury (MIRI), is particularly refractory to treatment [ 4 , 5 ]. (hindawi.com)
  • However, whether GRh2 has a protective effect on ischaemia/reperfusion (I/R) in the myocardium has yet to be elucidated. (spandidos-publications.com)
  • In this article, we present real-time NO dynamics in the myocardium during myocardial ischemia-reperfusion (IR) utilizing electrochemical NO microsensor. (intechopen.com)
  • CABG may be performed as an emergency procedure in the context of an ST-segment elevation MI (STEMI) in cases where it has not been possible to perform percutaneous coronary intervention (PCI) or where PCI has failed and there is persistent pain and ischemia threatening a significant area of myocardium despite medical therapy. (medscape.com)
  • Protection of the heart against injury from acute ischemia remains challenging for emergency physicians and cardiologists because there are no therapies proven to directly protect the heart against the deleterious effects of ischemia in humans. (mcw.edu)
  • The patient had severe cardiac dysfunction and atrial fibrillation and presented with acute ischemia in the right lower limb 24 h after receiving an inferior vena cava filter. (medscape.com)
  • BACKGROUND: Mild hypothermia, 32-35°C, reduces infarct size in experimental studies, potentially mediating reperfusion injuries, but human trials have been ambiguous. (lu.se)
  • The prevention of BBB breakdown and the subsequent vasogenic edema are important parts of the medical management of ischemic stroke. (nih.gov)
  • Imaging biomarkers are increasingly used to provide a better understanding of the pathophysiology of acute ischemic stroke. (ajnr.org)
  • The aim of this study was to systematically review the use of imaging biomarkers in randomized controlled trials in patients with acute ischemic stroke, exploring the purposes for which the imaging biomarkers were used. (ajnr.org)
  • We performed a systematic review of imaging biomarkers used in randomized controlled trials of acute ischemic stroke, in which a therapeutic intervention was trialed within 48 hours of symptom onset. (ajnr.org)
  • Treatment options for patients with acute ischemic stroke are limited. (ajnr.org)
  • In the treatment of acute ischemic stroke, immediate recanalization of the occluded artery, using systemic or local thrombolysis, is optimal for restoring the blood flow and rescuing the ischemic brain from complete infarction. (nih.gov)
  • Surprisingly, even in the non-ischemic arteries from the contralateral hemisphere and in the basilar artery, superoxide production was increased ∼ 4- to 6-fold at 24 h, but had returned to normal 72 h after stroke. (gla.ac.uk)
  • Multicenter cohort study of patients with acute ischemic stroke who underwent a brain computed tomography perfusion and were scheduled to undergo reperfusion therapy. (medscape.com)
  • Migraine is likely to increase individual vulnerability to ischemic stroke during the process of acute brain ischemia and might represent, therefore, a potential new therapeutic target against occurrence and progression of the ischemic damage. (medscape.com)
  • A large body of literature supports a link between migraine, especially migraine with aura, and ischemic stroke. (medscape.com)
  • Meng X, Zhang L, Han B and Zhang Z: PHLDA3 inhibition protects against myocardial ischemia/reperfusion injury by alleviating oxidative stress and inflammatory response via the Akt/Nrf2 axis. (spandidos-publications.com)
  • Therapeutic hypothermia (TH) aims to ameliorate further injury in infants with moderate and severe hypoxic ischemic encephalopathy (HIE). (nature.com)
  • And applications of electrochemical NO sensor for the evaluation of cardioprotective effects of therapeutic treatments such as drug administration and ischemic preconditioning are reviewed. (intechopen.com)
  • However, mitigation strategies to preserve cardiac function after an ischemic event have often only focused on individual therapeutic agents, and the results have not been ideal. (prohealth.com)
  • Here we review the current literature on scutellarin to provide a comprehensive understanding of the pharmacological activity, mechanism of action, toxicity, and therapeutic potential of scutellarin for the treatment of ischemia, diabetic complications, and other chronic diseases. (cdc.gov)
  • At 72 hours after reperfusion, renal function and morphology showed significant improvements in the EPCs-treated group. (annalsoftransplantation.com)
  • Renal ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI). (mdpi.com)
  • Renal ischemia-reperfusion injury (IRI) is considered as a major cause of acute kidney injury. (frontiersin.org)
  • Renal ischemia-reperfusion injury (IRI) is a common pathophysiological phenomenon in clinical settings. (frontiersin.org)
  • Renal ischemia: a new perspective. (bmj.com)
  • Apoptotic pathways in ischemic acute renal failure. (bmj.com)
  • Effects of ischemic preconditioning prot. (ogu.edu.tr)
  • Background: Ischemic preconditioning (IPC) is described as brief ischemia-reperfusion (I/R) cycles to induce tolerance to subsequent in response to longer I/R insults. (ogu.edu.tr)
  • RIPC: Remote ischemic preconditioning. (wjgnet.com)
  • Ischemic preconditioning (IPC) is an important endogenous adaptive phenomenon first described by Murry et al ( 1 ) in 1986. (spandidos-publications.com)
  • Alkan T (2009) Neuroproctective effects of ischemic tolerance (preconditioning) and postconditioning. (springer.com)
  • Zhang Y, Irwin MG, Wong TM (2004) Remifentanil preconditioning protects against ischemic injury in the intact rat heart. (springer.com)
  • Remote ischaemic preconditioning (RIPC) is known to minimise IRI in previous studies. (medsci.org)
  • Ischaemic preconditioning describes the phenomenon where transient and brief ischaemia confers protection against a subsequent prolonged and injurious period of ischaemia. (medsci.org)
  • Considering that tourniquet application during TKR is related to ischaemic injury, the organ protective effect of ischaemic preconditioning can have a beneficial role after tourniquet release during TKR. (medsci.org)
  • However, it is not easy to apply ischaemic preconditioning in a clinical setting because brief organ ischaemia should be preceded after real ischaemic time [ 8 ]. (medsci.org)
  • Meanwhile, the organ protective effect of ischaemic preconditioning could be induced when the episodic ischaemia is at distant tissues or organs, the concept being termed remote ischaemic preconditioning (RIPC) [ 9 ]. (medsci.org)
  • The application of RIPC into clinical fields is more useful than ischaemic preconditioning because it is easy to apply briefly preceding ischaemia to distant organs such as the limbs. (medsci.org)
  • Our results establish EPO as an important paracrine neuroprotective mediator of ischemic preconditioning. (jneurosci.org)
  • Cysteine hydropersulfide reduces lipid peroxidation and protects against myocardial ischaemia-reperfusion injury - Are endogenous persulfides mediators of ischaemic preconditioning? (southampton.ac.uk)
  • Considering these results, we conclude that L-carnitine has a protective effect against cardiac ischemic reperfusion injuries as a reduction of apoptotic cardiomyocytes. (vin.com)
  • Transient forebrain ischemia leads to delayed death of the CA1 neurons in the hippocampus. (nih.gov)
  • Immunohistochemical and biochemical investigations of Ca2+/calmodulin-dependent protein kinase II(CaM kinase II) and protein phosphatase (calcineurin) after transient forebrain ischemia demonstrated that the activity of CaM kinase II was decreased in the CA1 region of the hippocampus early (6-12 hours) after ischemia. (nih.gov)
  • The patient underwent right femoral-anterior tibial bypass with ischemic symptoms in the right lower extremity. (medscape.com)
  • 30%) with acute symptoms of right lower-extremity ischemia. (medscape.com)
  • IPC involves single or multiple brief periods of sublethal ischemia, which increase myocardial resistance to a greater subsequent insult. (spandidos-publications.com)
  • Surprisingly, Txnip-KO hearts had greater recovery of cardiac function after an ischemia-reperfusion insult. (jci.org)
  • IP is a biphasic phenomenon, with an early short-lasting phase of protection that develops within minutes from the initial ischemic insult and lasts ∼2 hr. (jneurosci.org)
  • Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling positive cells and expression of Bcl-2 and Bax in the hippocampal CA1 region were assessed after reperfusion. (springer.com)
  • Alpha compared to beta adrenergic contributions to dysrhythmias induced by left anterior descending coronary occlusion and by reperfusion were assessed in chloralose-anesthetized cats (n = 96). (jci.org)
  • Ventricular dysrhythmias induced by coronary occlusion alone (without reperfusion) were attenuated markedly by alpha-receptor blockade under conditions in which perfusion (measured with radiolabeled microspheres) within ischemic zones was not affected. (jci.org)
  • Alternative sympatholytic interventions including pretreatment with 6-hydroxydopamine to deplete myocardial norepinephrine from 8.8 +/- 1.4 to 0.83 +/- 0.2 ng/mg protein and render the heart unresponsive to tyramine (120 microgram/kg) attenuated dysrhythmias induced by both coronary occlusion and reperfusion in a fashion identical to that seen with alpha-receptor blockade. (jci.org)
  • 2003). In agreement with these observations, there is evidence that increased oxidative stress plays an important role in the pathogenesis of neurodegenerative diseases such as AD, PD, ischemic diseases and aging (Esposito et al. (lww.com)
  • Elevations in the expression of this enzyme may help to explain the role of the ET system in the pathogenesis of ischaemia/reperfusion injury following cardiac surgery and transplantation. (portlandpress.com)
  • To elucidate the cardioprotective mechanisms of mild hypothermia, we analyzed cardiac performance in a porcine model of ischemia/reperfusion, with serial cardiovascular magnetic resonance (CMR) imaging throughout one week using non-invasive pressure-volume loops. (lu.se)
  • Research done in animals shows that treatment with NAD+ precursors like NMN have cardioprotective effects against ischemia/reperfusion injury (4). (prohealth.com)
  • The pathophysiological nature of MIRI is the short-term disturbance of myocardial energy and metabolism caused by reflow after ischemia and hypoxia in the coronary artery and the dynamic changes in apoptosis and the prosurvival signaling pathways in response to related injury factors. (hindawi.com)
  • Given the central role that mitochondria play during hypoxia, we hypothesized that Txnip deletion would enhance ischemia-reperfusion damage. (jci.org)
  • Global hypoxia-ischemia interrupts oxygen delivery and blood flow to the entire brain. (cdc.gov)
  • Global brain hypoxia-ischemia during cardiac arrest has a long-term impact on processing and transfer of sensory information by thalamic circuitry. (cdc.gov)
  • We hypothesized that an imbalance of Ca2+/calmodulin dependent protein phosphorylation-dephosphorylation may be involved in delayed neuronal death after ischemia. (nih.gov)
  • Hypoxic ischemic encephalopathy (HIE) occurs in 1-6 per 1,000 live full-term births and is caused by the interruption of blood and/or oxygen supply to the brain in the perinatal period ( 1 , 2 ). (nature.com)
  • We investigated whether a personal history of migraine is associated with vulnerability to brain ischemia in humans. (medscape.com)
  • The microvascular and parenchymal organ damage induced upon ischemia tissue reperfusion is mainly attributed to the reactive oxygen-free radicals, and it has been demonstrated in many organs. (frontiersin.org)
  • The production of antioxidant enzymes that scavenge free radicals in ischemic tissue is then impaired, thereby exacerbating the damage caused by these free radicals in the post ischemic reperfusion tissue. (frontiersin.org)
  • 2. Siemionow M, Arslan E. Ischemia/reperfusion injury: a review in relation to free tissue transfers. (scielo.br)
  • Intra- and postoperative monitoring of flap microcirculation may provide useful information for better understanding and following-up the ischemia-reperfusion-related alterations in tissue perfusion 6 6. (scielo.br)
  • It is useful to think of an ischemic lesion as a densely ischemic core surrounded by better perfused "penumbra" tissue that is silent electrically but remains viable. (nih.gov)
  • During myocardial ischemia (lack of blood flow to the muscle tissue of the heart, commonly referred to as a "heart attack"), blood flow is interrupted because of damage to one or more of the coronary blood vessels that irrigate the heart. (prohealth.com)
  • In many cases, damage to heart tissue by reperfusion injury is greater than the damage done by the interruption of blood flow. (prohealth.com)
  • For the study, the researchers performed tests to measure the condition of cardiac tissue before and after an ischemic event and after perfusion was re-established. (prohealth.com)
  • The ischemic injury underlying these illnesses is complex, involving intricate interplays among many biological functions including energy metabolism, vascular regulation, hemodynamics, oxidative stress, inflammation, platelet activation, and tissue repair that take place in a context- and time-dependent manner. (cdc.gov)
  • but reperfusion may introduce additional harm to the tissue through a process known as ischemia/reperfusion injury. (cdc.gov)
  • Thus, although Txnip deletion suppresses mitochondrial function, protection from myocardial ischemia is enhanced as a result of a coordinated shift to enhanced anaerobic metabolism, which provides an energy source outside of mitochondria. (jci.org)
  • We previously demonstrated that chronic pretreatment with a thiazolidinedione peroxisome proliferator-activated receptor (PPAR)-γ activator, troglitazone, improves recovery of left ventricular (LV) function and substrate metabolism after ischemia and reperfusion, without causing arrhythmias. (diabetesjournals.org)
  • While effective early reperfusion of the criminal coronary artery after a confirmed AMI is the typical treatment at present, collateral myocardial ischemia-reperfusion injury (MIRI) and pertinent cardioprotection are still challenging to address and have inadequately understood mechanisms. (hindawi.com)
  • Heusch G: Myocardial ischaemia-reperfusion injury and cardioprotection in perspective. (spandidos-publications.com)
  • Heusch G: Molecular basis of cardioprotection: Signal transduction in ischemic pre-, post-, and remote conditioning. (spandidos-publications.com)
  • In this study, effects of L-Carnitine on apoptosis in the ischemic isolated rat hearts were investigated. (vin.com)
  • At the end of reperfusion, Immunohistochemical detection of apoptotic cells was performed by using an in situ apoptosis detection kit. (vin.com)
  • Alpha receptor blockade with either phentolamine or prazosin significantly reduced the number of premature ventricular complexes during coronary reperfusion (321 +/- 62-14 +/- 10 premature ventricular complexes, P less than 0.001), abolished early ventricular fibrillation (from 25% in controls to 0%), and prevented the increase in idioventricular rate seen with coronary reperfusion. (jci.org)
  • However, while myocardial reperfusion is well established, the process itself can trigger myocardial reperfusion injury by causing further cardiomyocyte death through multiple pathophysiological mechanisms [ 3 - 5 ]. (hindawi.com)
  • Conceptual diagram of the development and unknown mechanisms of myocardial ischemia-reperfusion injury. (hindawi.com)
  • CONCLUSION: Using non-invasive pressure-volume loops by CMR, we observed that mild hypothermia at reperfusion alleviates the heart's work after ischemia/reperfusion injuries during the first week and preserves short-term cardiac performance. (lu.se)
  • Those factors include mechanical and reperfusion injuries, ischemia, various burns, UV rays, and radiation [ 4 - 6 ]. (hindawi.com)
  • The purpose of this study was to investigate the ischemic tolerance effect of Rosmarinus officinalis leaf hydro-alcoholic extract (RHE). (nih.gov)
  • Tourniquet release during the late period of TKR can induce ischaemic-reperfusion injury, eliciting the activation of neutrophils, circulating pro-inflammatory cytokines, and reactive oxygen species [ 2 , 3 ]. (medsci.org)
  • Sun W, Wang Z, Sun M, Huang W and Wang Y and Wang Y: Aloin antagonizes stimulated ischemia/reperfusion-induced damage and inflammatory response in cardiomyocytes by activating the Nrf2/HO-1 defense pathway. (spandidos-publications.com)
  • Abouzaki NA, Christopher S, Trankle C, Van Tassell BW, Carbone S, Mauro AG, Buckley L, Toldo S and Abbate A: Inhibiting the inflammatory injury after myocardial ischemia reperfusion with plasma-derived Alpha-1 Antitrypsin: A post hoc analysis of the VCU-α1RT study. (spandidos-publications.com)
  • When blood flow is re-established (reperfusion), a series of inflammatory responses take place because of the damage sustained by the tissues affected by the previous lack of blood. (prohealth.com)
  • METHODS AND RESULTS: Normothermia and Hypothermia groups sessions (n=7+7 pigs, nonrandom allocation) were imaged with CMR at baseline and subjected to 40 minutes of normothermic ischemia by catheter intervention. (lu.se)
  • For non-ST-segment-elevation myocardial infarction, reperfusion is via percutaneous intervention or coronary artery bypass graft surgery. (msdmanuals.com)
  • Thereafter, the Hypothermia group was rapidly cooled (mean 34.5°C) for 5 minutes before reperfusion. (lu.se)
  • The development of effective neuroprotection methods and the establishment of reliable imaging modalities for an early and accurate diagnosis of the extent and degree of the ischemia are imperative. (nih.gov)
  • There are not enough reports about its anti-apoptotic effects during ischemia/reperfusion. (vin.com)
  • Retinal ischemia/reperfusion (I/R) injury can cause severe vision impairment. (mdpi.com)
  • Isolated rat hearts perfused with Krebs-Henseleit buffer were subjected to 30min of normothermic perfusion, then 4h of cardioplegic arrest at 4°C with St Thomas' Hospital solution, followed by reperfusion for 2h. (portlandpress.com)
  • As such, new drugs that would complement reperfusion by providing neural and cardiovascular protection and by targeting multiple abnormalities in ischemia are receiving increased attention. (cdc.gov)
  • Before ischemia, acute troglitazone treatment had no effect on LV function, electrocardiogram, or substrate utilization. (diabetesjournals.org)
  • Effect of short-term ischemia on microcirculation and wound healing of adipocutaneous flaps in the rat 1 1 Research performed at Department of Operative Techniques and Surgical Research, Institute of Surgery, Faculty of Medicine, University of Debrecen, Hungary. (scielo.br)
  • We aimed to follow-up the effect of ischemia on adipocutaneous flaps' wound healing and microcirculation. (scielo.br)