L-arginine improves endothelial function, independently of arginine uptake, in aortas from chronic renal failure female rats.

Endothelial cell dysfunction (ECD) is a common feature of chronic renal failure (CRF). Defective nitric oxide (NO) generation due to decreased endothelial nitric oxide synthase (eNOS) activity is a crucial parameter characterizing ECD. Decreased activity of cationic amino acid transporter-1 (CAT-1), the selective arginine transporter of eNOS, has been shown to inhibit eNOS in uremia.

Vipera aspis venom reduces lethality and down-regulates tumor necrosis factor-alpha in a rat model of LPS-induced sepsis.

Objectives: Sepsis and septic shock are major causes of morbidity and mortality in critically-ill patients. Sepsis constitutes the systemic response to infection, that is predominantly mediated by the pro-inflammatory cytokines TNF-alpha and IL-1beta. Hence, cytokine modulation provides a promising target for the treatment of sepsis.

Cardioplegic ischemia or reperfusion: which is a main trigger for tumor necrosis factor production?

Background: Tumor necrosis factor alpha (TNF-alpha) is a key cytokine in the pathogenesis of ischemia-reperfusion injury (I/R) that also possesses negative inotropic and direct cardiotoxic effects. We investigated whether myocardial ischemia and/or reperfusion is the trigger for TNF-alpha synthesis and whether TNF-alpha release is time dependent.

Methods: Isolated rat hearts undergoing 30 min of coronary perfusion with modified Krebs-Henseleit solution followed by cardioplegic arrest for 60 min of global cardioplegic normothermic ischemia (GCI) and 30 min of reperfusion using a modified Langendorff model.

The potential advantage of "no-touch" aortic technique in off-pump complete arterial revascularization.

Objectives: Off-pump coronary artery bypass grafting (OPCAB) and complete arterial revascularization without proximal anastomosis to the aorta may decrease neurological events after open-heart surgery. Few reports exist regarding the combination of OPCAB and complete arterial revascularization exploring the theoretical advantage of avoiding manipulation of the aorta. We review our results in 110 patients who underwent multiple grafts off-pump complete arterial revascularization.

Heparin added to cardioplegic solution inhibits tumor necrosis factor-alpha production and attenuates myocardial ischemic-reperfusion injury.

Objectives: Tumor necrosis factor (TNF)-alpha is known to be a proinflammatory cytokine that has a pronounced negative inotropic effect and plays an important role in ischemic-reperfusion injury.

Methods: Twenty isolated rat hearts were randomly divided equally into two groups (heparin and non-heparin) and were perfused with a Krebs-Henseleit solution using a modified Langendorff model. The influence of heparin on the synthesis and release of TNF-alpha by isolated rat hearts after 1 h of global cardioplegic ischemia and on left ventricular (LV) performances during 30 min of postischemic reperfusion was investigated.

Thermo-wrap technology preserves normothermia better than routine thermal care in patients undergoing off-pump coronary artery bypass and is associated with lower immune response and lesser myocardial damage.

Objective: Perioperative hypothermia might be detrimental to the patient undergoing off-pump coronary artery bypass surgery. We assessed the efficacy of the Allon thermoregulation system (MTRE Advanced Technologies Ltd, Or-Akiva, Israel) compared with that of routine thermal care in maintaining normothermia during and after off-pump coronary artery bypass surgery.

Methods: Patients undergoing off-pump coronary artery bypass surgery were perioperatively and randomly warmed with the 2 techniques (n = 45 per group).

Pharmacological preconditioning with monophosphoryl lipid A improves post ischemic diastolic function and modifies TNF-alpha synthesis.

Objective: Pharmacologic preconditioning represents an attractive myocardial protection strategy. Tumor necrosis factor-alpha plays an important role in myocardial ischemia-reperfusion injury. We aimed to determine the effect of Monophosphoryl lipid A-induced delayed preconditioning on diastolic and systolic left ventricular function and tumor necrosis factor-alpha synthesis during ischemia and reperfusion.

Use of intraoperative epiaortic ultrasonography to delineate aortic atheroma.

Objective: A cerebrovascular accident (CVA) is a devastating complication of coronary artery bypass grafting (CABG) and a major cause for morbidity and mortality. Aortic manipulation, cannulation, and clamping during CABG may lead to release of atheromatous material from the ascending aorta, which may cause a CVA. This study assessed the hypothesis that the use of intraoperative epiaortic ultrasonography (EAUS) would supplement imaging information with that derived from manual aortic palpation and influence the surgical decision-making approach accordingly.

Effect of tumor necrosis factor-alpha on endothelial and inducible nitric oxide synthase messenger ribonucleic acid expression and nitric oxide synthesis in ischemic and nonischemic isolated rat heart.

Objectives: The present study aimed to investigate the influence of endogenous tumor necrosis factor-alpha (TNF-alpha) that was synthesized during ischemia and exogenous TNF-alpha on endothelial and inducible nitric oxide synthase (eNOS and iNOS) messenger ribonucleic acid (mRNA) expression and nitric oxide (NO) production in the isolated rat heart.

Background: Tumor necrosis factor-alpha is recognized as being a proinflammatory cytokine with a significant cardiodepressant effect. One of the proposed mechanisms for TNF-alpha-induced cardiac contractile dysfunction is increased NO production via iNOS mRNA upregulation, but the role of NO in TNF-alpha-induced myocardial dysfunction is highly controversial.

Tumor necrosis factor as a mediator of cardiac toxicity following snake envenomation.

Objective: To investigate the possible role of tumor necrosis factor in mediating cardiotoxicity following venom injection in a rat.

Design: A randomized controlled experimental study using a Langendorff isolated heart model.

Setting: Animal laboratory.

Technical aspects of composite arterial grafting with double skeletonized internal thoracic arteries.

Background: Complete myocardial revascularization with internal thoracic arteries (ITAs) improves long-term survival and decreases the rate of repeat operations, compared to vein grafts. Adequate length of the graft in coronary artery bypass graft (CABG) surgery is essential for providing complete arterial revascularization. Extra length can be obtained by skeletonization of both ITAs.

Electromechanical impairment of human auricle and rat myocardial strip subjected to exogenous oxidative stress.

Objective: Animal myocardial dysfunction induced by remote ischemia-reperfusion (IR) was shown to be partly accomplished via a direct effect of the pro-oxidant xanthine oxidase (XO). This direct remote effect was not tested in humans. We now assessed the performance of human auricles in the presence of solutions containing XO and/or allopurinol and compared them to those of rat myocardial strips.