Introduction Autophagy is well known as one of the biogenic responses against various stresses, which possesses the benefi cial roles for survival, but little is known about the dynamics and its signifi cance during the septic condition. We hypothesized that autophagy is induced during the septic condition, and contributes to protect from tissue damage which subsequently leads to organ dysfunction. We confi rm whether the autophagic process is accelerated or sustained in an acute phase of sepsis and we also determine its physiological role. Methods Sepsis was induced by cecal ligation and puncture (CLP) in mice. We examined the kinetics of autophagosome and auto lysosome formation which may explain the status of autophagy by western blotting, immunohistochemistry, and electron microscopy. To investigate a precise role of autophagy in CLP-induced sepsis, chloroquine, an autophagy inhibitor, was administered to the CLP-operated mice, and blood chemistry, pathology of the liver and survival were evaluated. Results Autophagy demonstrated by the ratio of LC3-II/LC3-I was induced over the time course up to 24 hours after CLP. The ratio was particularly increased in the liver, heart and spleen. Autophagosome formation became maximal at 6 hours and declined by 24 hours after CLP. Autolysosome formation as evaluated by both fusion of GFP-LC3 dots with LAMP1 immunohistochemistry and electron microscopy was also increased after the procedure. Furthermore, inhibition of autophagy by chloroquine during the CLP procedure resulted in elevation of serum AST levels, and signifi cantly increased mortality in mice. Conclusion Autophagy was induced in several organs over the time course of the CLP sepsis model and then the process was gradually completed to degradation of the components. Our data suggest autophagy plays a protective role in organ dysfunction in sepsis. P2Reversible depressive eff ect of TNFα on a model of isolated perfused rat heart BV Nguyen Introduction Acute myocardial depression in septic shock is common [1]. Myocardial depression is mediated by circulating depressant substances, which until now have been incompletely characterized [2].The aim of our study was to observe the eff ects of TNFα on the model of perfused rat heart. Methods After profound anesthesia with pentothal, the Wistar rats were killed by exsanguination. After sternotomy, the heart was taken and connected to the Langendorf column. The apex of the heart was hooked to a strength sensor. Biopac student laboratory software was used to record and analyse heart contractions. Contractions were recorded every 5 minutes during periods of 20 minutes. Control measurements were fi rst recorded. We measured four parameters: heart rate, contraction force, speeds of contraction and relaxation for control, during TNFα (20 ng/ml) exposure and after removal of TNFα. We express the variations of parameters as percentage of the control ± SEM. A paired t test was used to compare heart rate, contraction amplitude, speeds of contraction and relaxation with TNFα and ...

BackgroundHaemodilution and hypothermia induce coagulopathy separately, but their combined effect on coagulation has not been widely studied. Fibrinogen concentrate can correct dilutional coagulopathy and has an additional effect when combined with factor XIII concentrate. However, their effect on dilutional coagulopathy concomitant with hypothermia has not been studied previously. Free oscillation rheometry – FOR (Reorox®) – is a novel viscoelastic haemostatic assay that has not been studied in this context before.MethodsBlood from 10 healthy volunteers was diluted by 33% with hydroxyethyl starch or Ringer’s acetate solutions. Effects of fibrinogen added in vitro with and without factor XIII were studied at 33°C and 37°C. Coagulation velocity (coagulation time) and clot strength (elasticity) were assessed with FOR. Coagulation was initiated in vitro with thromboplastin alone, or thromboplastin plus a platelet inhibitor.ResultsHydroxyethyl starch increased the coagulation time and decreased clot strength significantly more than Ringer’s acetate solution, both in the presence and absence of a platelet inhibitor. There was a significant interaction between haemodilution with hydroxyethyl starch and hypothermia, resulting in increased coagulation time. After addition of fibrinogen, coagulation time shortened and elasticity increased, with the exception of fibrinogen-dependent clot strength (i.e., elasticity in the presence of a platelet inhibitor) after hydroxyethyl starch haemodilution. Factor XIII had an additional effect with fibrinogen on fibrinogen-dependent clot strength in blood diluted with Ringer’s acetate solution. Hypothermia did not influence any of the coagulation factor effects.ConclusionsBoth haemodilution and mild hypothermia impaired coagulation. Coagulopathy was more pronounced after haemodilution with hydroxyethyl starch than with Ringer’s acetate. Addition of fibrinogen with factor XIII was unable to reverse hydroxyethyl starch induced clot instability, but improved coagulation in blood diluted with Ringer’s acetate solution. Fibrinogen improved coagulation irrespective of hypothermia.

SummaryPlasma fibrinogen concentration is important for coagulopathy assessment, and is most commonly measured using the Clauss method. Several factors, including device type and reagent, have been shown to affect results. The study objective was to evaluate performance and repeatability of the Clauss method and to assess differences between measurements performed during and after cardiopulmonary bypass (CPB), by testing plasma samples from patients undergoing cardiac surgery with CPB. Samples were collected from 30 patients before surgery, approximately 20 minutes before weaning from CPB, and 5 minutes after CPB and protamine. Fibrinogen concentration was determined using the Clauss method at six quality-controlled specialised laboratories, according to accredited standard operating procedures. Regarding within-centre agreement for Clauss measurement, mean differences between duplicate measurements were between 0.00 g/l and 0.15 g/l, with intervals for 95% limits of agreement for mean Bland-Altman differences up to 1.3 g/l. Regarding between-centre agreement, some mean differences between pairs of centres were above 0.5 g/l. Differences of up to ~2 g/l were observed with individual samples. Increased variability was observed between centres, with inter-class correlation values below 0.5 suggesting only fair agreement. There were no significant differences in fibrinogen concentration before weaning from CPB and after CPB for most centres and methods. In conclusion, considerable differences exist between Clauss-based plasma fibrinogen measured using different detection methods. Nevertheless, the similarity between measurements shortly before weaning from CPB and after CPB within centres suggests that on-pump measurements could provide an early estimation of fibrinogen deficit after CPB and thus guidance for haemostatic therapy.

The selectivity of the intracellular 85 kDa phospholipase A2 (PLA2-85) towards fatty acids closely related to arachidonic acid has been investigated, using purified PLA2-85 from J774 cells and mixed phospholipids, dually acyl-chain-labelled in the sn-2 position. In parallel experiments, we assessed the acyl-chain selectivity of the release process in intact, dually labelled, peritoneal mouse macrophages responding to either calcium ionophore or zymosan beads in the presence of indomethacin and BSA. The results obtained in the two systems were very similar, which supports previous evidence that PLA2-85 is responsible for stimulus-induced release of eicosanoid precursor in mouse macrophages. In the in vitro system, PLA2-85 was found to exhibit a moderate selectivity towards C20 acyl chains differing in double-bond structure, while the sensitivity to acyl-chain length was more pronounced. Together with previous data, these results demonstrate a striking preference for C20 over either C18 or C22 unsaturated acyl chains.