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Objective: We studied the protective effects of postconditioning (PS) in healthy and hypercholesterolemic rats after renal ischaemia-reperfusion (IR) injury. We aimed to examine cytokine expression and apoptosis in tissue damage after revascularisation (TNF-α levels in serum and tissue). Methods: Male Wistar rats (n = 32) were divided into four groups. The animals of normal feed groups (NF) were fed with normal rat chow and the cholesterol feed groups (CF) were fed with 1.5% cholesterol containing diet for 8 weeks. Anaesthetized rats underwent a 45-min cross-clamping in both kidney pedicles. Ischaemia was followed by 120-min reperfusion with or without PS protocol (group PS vs. IR). Postconditioning was induced by four intermittent periods of ischaemia-reperfusion of 15-s duration each. Serum cholesterol, triglyceride, urea and creatinine levels were determined. Proinflammation was characterized by the measurement of serum TNF-α. Tissue injury in kidney was determined by formaline-fixed, paraffin-embedded tissue sections. Tissue TNF-α levels were determined by immunohistochemistry. Results: Significant elevation was observed in serum TNF-α level after IR injury in normal feed groups, which was reduced by PS. In CF group neither the elevation nor the postconditioning induced reduction were as significant as in the NF groups. In normal feed group PS caused a significant reduction in tissue TNF-α level which was significantly higher in CF. Conclusions: Ischaemic postconditioning proved to be an effective defense against IR in NF groups, but it was ineffective in CF groups in kidney tissue. [ABSTRACT FROM AUTHOR]

Objective: Leukocyte activation is thought to be responsible for the adverse effects and postoperative complications following cardiopulmonary bypass (CPB). A novel cell surface molecule, CD97, is a sensitive marker of leukocyte and primary lymphocyte activation. The present study aimed to determine the activation of different leukocyte subsets by comparing the expression of CD97 and adhesion molecules (CD11, CD18) in patients receiving coronary surgery with or without CPB. Methods: 30 patients were enrolled and scheduled for coronary bypass surgery under CPB (20 patients, group A) and with off-pump (OP) operation (10 patients, group B). Blood samples were taken before and during surgery, and over the following first week. Results: Here, we report an early decrease in CD97 expression of granulocytes (PMN) and monocytes (MC) followed by an intensive increase reaching the maximum on postoperative days 2 and 3 in patients operated with CPB. The rate of active CD97-positive lymphocytes showed a marked, gradual increase until postoperative day 3 and remained elevated up to day 7 after CPB. OP surgery resulted in moderate alteration in the presence of CD97 on PMN, MC and lymphocytes. The expression of adhesion molecules was similar to CD97 in all leukocyte subsets. Conclusion: The findings about CD97 expression suggest considerable leukocyte activation following coronary bypass with CPB compared to OP surgery. The collected data show that the lymphocytes are highly activated and involved in leukocyte sequestration after CPB. Moreover, the importance of CD97 in CPB-related inflammatory response can be stated. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Nuclear factor (NF)-κB and activation protein (AP)-1 transcription factors play an important role in the signal transduction of delayed ischaemic preconditioning (PC) leading to myocardial cytoprotection. Because the exact mechanism of the activation of these factors is still not clear, we aimed to monitor the time fluctuation of NF-κB and AP-1 induction in an in vivo animal model. Furthermore, we measured the induction rate of these factors using repeated cycles of PC. Following median thoracotomy, anaesthetized animals (24 New Zealand White rabbits) were subjected to ischaemic PC by occlusion of the left anterior descending coronary artery for 5 min. After 10 and 30 min, and 1, 2, 3 and 4 h of reperfusion, tissue samples were taken from the ischaemic myocardium, and the DNA binding activity of the transcription factors was measured with electrophoretic mobility shift assay. A further 12 animals were subjected to 2 ×, 3 × or 4 × 5-min ischaemic PC, and after a 30-min or 1-hour reperfusion period, we investigated the possible modulation of NF-κB and AP-1 induction. Our results show significant, biphasically increased NF-κB activity with peak levels at 30 min and 3 h of reperfusion in preconditioned myocardium. AP-1 increased monophasically, with the peak level at 1 h of reperfusion. Repeated PC stimuli enhanced the activity of both transcription factors analyzed, but there was no significant correlation between the number of cycles and the rate of activation. Our results show that the activation of NF-κB and AP-1 have a specific time curve, and the induction of these factors is only slightly influenced by the number of PC cycles. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

This study aims to assess the applicability of osteoprotegerin (OPG) and receptor activator of NF-kB ligand (RANKL) as early markers for characterising of bone healing and adequate fracture management. 30 elderly patients admitted to the ward with acute trochanteric fracture. All patients underwent reamed and unreamed intra-medullar osteosynthesis within 24 h using Howmedica Trochanteric Gamma Nail. OPG and RANKL levels were determined in the patients' sera at certain time periods. The most dramatic changes of OPG and RANKL levels were displayed during the first week in both groups. Moreover the different operative techniques could be clearly separated on the basis of biochemical results.

The article reports on a study conducted to measure the oxidative stress parameters and the leukocyte function in patients suffering from acute pulmonary embolism. 9 patients with acute pulmonary embolism undergoing thromboiysis by ultra-high dose streptokinase, or alteplase were studied. Blood samples were collected before treatment and 8 h, 1,3, 5 and 30 days after treatment. The study shows that pulmonary embolism induced oxidative stress that was further enhanced following thromboiysis. Decreased adhesion molecule expression of circulating leukocytes reflects the pathological leukocyte endothelial cell interactions in the first hour of thrombolysis.

In the present study researchers investigated the effect of acetylsalicylic acid (ASA), on the activation and nuclear translocation of NF-kB in the preconditioned myocardium. It is supposed that ASA can inhibit NF-kB dependent gene activation in the myocardium through inhibiting the proteosomal degradation. Researchers conclude that administration of ASA either at antithrombotic doses, or at analgetic, antipyretic doses does not interfere with the cardioprotective effects of late PC against infarction, but using high dose of ASA in clinical practice can inhibit the endogenous adaptation of the myocardium.