Curcumin (diferuoylmethane) is a natural compound with anticareinogenic activities which is able to exert either proapoptotic or antiapoptotic effects in different cell types. This paper focuses on the sequence and extent of primary events induced by curcumin, in comparison with those occurring during dexamethasone-induced apoptosis in rat thymocytes. It also presents annexin VI-FITC as a new probe for studying membrane asymmetry. Curcumin readily penetrates into the cytoplasm, and is able to accumulate in membranous structures such as plasma membrane, endoplasmic reticulum and nuclear envelope. Curcumin-treated cells exhibit typical features of apoptotic cell death, including shrinkage, transient phosphatidylserine exposure, increased membrane permeability and decrease in mitochondrial membrane potential. However, nuclei morphology, DNA fragmentation, the extent and time-course of membrane changes are different from those observed during dexamethasone-induced apoptosis, suggesting that, despite many similarities, the mode of action and the events triggered by cnrcumin are different from those occurring during typical apoptosis.© In this paper, we analyzed the primary effects of the presence of CUR in rat thymocytes, and compared the sequence and extent of CUR-evoked events with those occurring during the typical apoptotic program induced by dexamethasone (DEX). The fluorescence and lipophilic properties of CUR [12] provided the basis for the search of its cellular localization and for analyzing the local effects on the structure and function of cellular membranes. Plasma membrane asymmetry was studied by a new fluorescence probe, i.e. annexin VI (Anx VI), isolated from porcine liver and coupled with FITC. We could investigate other parameters such as plasma membrane permeability, mitochondrial membrane potential, as well as other typical apoptotic features ,i.e. changes in cell volume, nucleus morphology and DNA fragmentation. Materials and methods

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Catheter-related bacteremia (CRB) is a typical complication of hemodialysis catheter use. Catheter lumen colonization by pathogens is regarded as a direct cause of CRB. Once settled, the catheter biofilm increases the risk of developing infection, thus necessitating insertion replacement and antibiotic treatment. The study assessed the self-sufficient efficacy of taurolidine-citrate-heparin lock solution in eradicating catheter biofilm bacteria and keeping it sterile in patients on hemodialysis. Twenty-nine chronic patients on hemodialysis with tunneled and nontunneled catheters locked with a heparin filling (the mean time of heparin lock use -30.1 ± 2.0 days) and subsequently converted to a taurolidine-citrate-heparin filling were included. Peripheral vein and catheter lumen blood cultures were obtained before the filling change and after taurolidine-citrate-heparin lock use (mean time 33.8 ± 7.6 days). Twenty-four participants with tunneled and nontunneled catheters locked with taurolidine-citrate-heparin filling served as the control group. During the heparin-locking period, CRB was diagnosed in 3 cases (only nontunneled catheters). The catheter blood cultures findings were positive in 23 patients (10 temporary and 13 permanent catheters), whereas both the catheter and peripheral vein blood cultures were sterile in 3 of 29 subjects (only permanent catheters). Irrespective of catheter type (tunneled or nontunneled), repeated culture revealed no pathogens in any of the 23 patients with initial positive catheter blood culture, after the use of taurolidine-citrate-heparin filling. No positive blood culture was noted in the control group. The taurolidine-citrate-heparin lock solution effectively eradicated pathogens from nontunneled and tunneled catheter biofilms and helped to maintain catheter lumen sterility.

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