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Multifrequency phase fluorometry was used to determine the lifetime distributions of 1,6 diphenyl-1,3,5-hexatriene in 1-palmitoyl-2 linoleoyl phosphatidylcholine small unilamellar vesicles containing 2% incorporation of phospholipid hydroperoxides. A biexponential decay was observed in both vesicle preparations over a temperature range of 5 to 35 degrees C. Vesicles containing phospholipid hydroperoxides showed an overall longer lifetime as well as a greater distribution in width. These findings suggest that phospholipid hydroperoxides create structural heterogeneity in membrane structure.

The effect of phospholipid hydroperoxides and alcohols on membrane order and dynamics was studied by using membrane spin label 3-doxyl-5-alpha-cholestane for the angle-resolved electron spin resonance measurements and fluorescent probe 1,6-diphenyl-1,3,5-hexatriene for the angle-resolved fluorescence depolarization measurements. The effect on membrane reorientation dynamics is negligible. However, small amounts of oxidatively modified phospholipids within the phosphatidylcholine or dilinoleoylphosphatidylcholine membranes have significant structural effects as the molecular orientation order of the probes is strongly decreased.

Background: Rapid and reliable exclusion of acute myocardial infarction during emergency department triage is an important clinical need. The purpose of this study was to evaluate the potential role of copeptin, a marker of acute endogenous stress, together with high sensitive troponin-I for a rapid and early rule-out of acute myocardial infarction., Methods: Copeptin and myoglobin were measured in 80 subjects presenting to the emergency department with chest pain and symptoms suggestive of acute myocardial infarction, 46 patients had a negative high sensitive troponin-I concentration at presentation, 3, 6 and 12 hours; whereas 34 patients had negative or very low high sensitive troponin-I at presentation, but rising troponin values at 3, 6 and 12 hours., Results: Copeptin was significantly higher in patients with evidence of myocardial damage (median 92.2 pmol/L vs 8.5 pmol/L, p < 0.0001). The area under the receiver-operating characteristic curve (AUC) for copeptin at initial presentation was 0.86 (95 % confidence interval, CI: 0.76 to 0.93), which was significantly higher than 0.68 (95% CI: 0.57 to 0.78, p < 0.05) for myoglobin but not significantly different from 0.88 (95% CI: 0.79 to 0.93) for high sensitive troponin-I. The combination of high sensitive troponin-I and copeptin resulted in an AUC of 0.94 (95% CI: 0.86 to 0.98), while the combination of high sensitive troponin-I and myoglobin results in an AUC of 0.89 (95% CI: 0.81 to 0.95)., Conclusions: Copeptin concentrations are more sensitive than myoglobin as an early marker of myocardial damage. Although copeptin provides significant incremental value on top of high sensitivity troponin-I, myoglobin does not.

Sepsis is one of the main causes of death in critically ill patients worldwide, and in many cases it is associated with renal and/or other organ failure. However, we do not have a unique efficient therapy to reduce this extremely high mortality rate. In the last years interest around the use of extracorporeal blood purification techniques has increased. One of the emerging treatments in patients with severe sepsis and septic shock is coupled plasma filtration adsorption (CPFA), a novel extracorporeal blood purification therapy aimed at a nonselective reduction of the circulating levels and activities of both pro- and anti-inflammatory mediators. Early experimental studies and the following clinical trials have demonstrated impressive results regarding hemodynamics and respiratory parameters, even in patients without concomitant acute renal injury, paralleled by a quick tapering of vasoactive drugs. Considering the still high morbidity and mortality rates in septic shock patients, this new blood purification technique seems to have benefits when applied early in the course of sepsis, also without renal indications, suggesting that it might be performed to prevent rather than to treat acute kidney injury.