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Hyperoxia reduces small bowel injury, accelerates enterocyte turnover, and improves intestinal rehabilitation after IR.

Background: Serum oxidative stress (OS) level has an important role in the inflammatory process of heart failure. Hypothesis:The study was designed to analyze serum OS levels in chronic heart failure (HF) patients and to examine the relation between OS levels and other clinical and prognostic parameters of HF. Methods: We studied 82 consecutive chronic symptomatic HF patients with systolic LV dysfunction (ejection fraction < 45%). The serum OS level was determined using thermochemiluminescence assay. We compared the serum OS levels with patients' clinical and prognostic parameters. Results: Higher serum OS levels were associated with higher New York Heart Association class (P = .01), worse renal function (serum urea, creatinine, and creatinine clearance) (P<.001) and higher serum levels of hs-C-reactive protein and N-terminal pro brain natriuretic peptide (P = .001, P<.001, respectively). Conclusions: In chronic systolic HF patients, high serum OS levels correlate with advanced disease and known markers of poor prognosis. IntroductionHeart failure (HF) is a major cardiovascular health problem, associated with high mortality and morbidity. Several studies suggested that inflammation has an important role in HF progression. Serum oxidative stress (OS) level is a crucial element of the inflammatory process, owing to the accumulation of reactive oxygen/nitrogen species that might provoke and exacerbate the myocardial damage of the already failing heart. 1 Several medications claim to have at least some beneficial effects through the antioxidant potential. 2 -6 The thermochemiluminescence (TCL) oxidiziability assay (Lumitest Ltd., Haifa, Israel), measures the OS level via photon emission counting from excited carbonyls in biological macromolecules. 7 TCL measurements were previously compared to other well accepted methods, which measure serum oxidative stress level via oxidation of lipids or proteins. 8 As we demonstrated before, TCL measurements were highly correlated with thiobarbituric acid reactive substances-(TBA assay), as well as with protein carbonyl formation (r = 0.99, r = 0.98, P<.01, respectively). 7 In this study, we investigated serum OS levels in chronic HF patients and examined the relation between OS levels and other clinical and laboratory prognostic parameters.

Objectives: Inflammation and serum oxidative stress (OS) are important components in heart failure (HF) deterioration. In this study we tested the hypothesis that an increase in patients’ sera OS levels is associated with acute HF (AHF) readmissions. Methods: Thirty consecutive patients (mean age 71 ± 10 years) admitted with AHF were included in the study. Serum OS in these patients was measured in-hospital and repeatedly after discharge over a period of 8 weeks of follow-up in which we reordered patients’ HF readmissions. Of the 30 patients, 13 (43%) were readmitted (RAD group) and 17 (57%) did not require readmission (NRAD group). Results: OS levels before discharge from the first hospital admission in the 2 groups were similar (p = 0.84 and p = 0.56, respectively). However, using repeated measures ANOVA, we found that the interaction between the time points and the 2 groups of patients (RAD and NRAD) was statistically significant (p = 0.037). It is important to note that OS serum levels were more predictive of HF readmissions than were repeated simultaneous serum measurements of NT-proBNP (p = 0.97). Conclusions: Increased OS levels in AHF patients, after they have been discharged from the hospital, are associated with higher HF readmission rates. In AHF, OS is a dynamic parameter associated with HF deterioration.

Detection of electronically excited species (EES) in body fluids may constitute an important diagnostic tool in various pathologies. Examples of such products are triplet excited carbonyls (TEC), which can be a source for photon emission in the 400-550 nm range. The aim of the present study was to determine the actual contribution of lipid and protein components (protein carbonyls) to photon emission generated by thermochemiluminescence (TCL) during the heating of biological fluids. In this study, a new TCL Photometer device, designed by Lumitest Ltd, Israel, was used. Samples were heated to a constant temperature of 80 +/- 0.5 degrees C for 280 s and photon emission was measured at several time points. In order to compare the results of TCL measurements to conventional methods of detecting lipid and protein oxidation, each examined sample was also heated in a waterbath at 80 degrees C for 10-280 s. Lipid and protein oxidation were subsequently measured using conventional methods. The TCL of four polyunsaturated fatty acids (PUFA) with three to six double bonds was measured. The elevation of the PUFA TCL amplitude correlated with the increase in the number of double bonds of PUFA. A correlation between the increase in TCL intensity and protein carbonyl generation in bovine serum albumin (BSA) was also observed. In the venous blood serum, our study showed that an increase of TCL intensity during heating reflected the cleavage of TEC of lipid origin. Our study suggests that biological molecules such as proteins, lipids and other molecules, which may become unstable during heating, are capable of generating EES. We demonstrated that a TCL curve can be used as a kinetic model for measuring oxidative processes, which reflects modifications of different molecules involved in the oxidative stress phenomena.

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Purpose The present study evaluated the association between oxidative parameters in embryo cryopreservation medium and laboratory and clinical outcomes. Methods This prospective laboratory study was conducted in an IVF unit in a university-affiliated hospital with 91 IVF patients undergoing a frozen-thawed embryo transfer cycle. Following thawing, 50 μL of embryo cryopreservation medium was retrieved from each cryotube and tested by the thermochemiluminescence (TCL) assay. TCL amplitudes after 50 (H1), 150 (H2), and 280 s (H3) were recorded in counts per second (CPS) and the TCL ratio determined for comparison with implantation and pregnancy rates. Results A total of 194 embryos were transferred in 85 frozenthaw cycles. Twenty-one pregnancies (24.7 %) occurred. Implantation and overall and clinical pregnancy rates were higher when the median TCL H1 amplitude was <32 CPS compared to ≥32 CPS (14.6 vs. 5.3 %, 37.5 vs. 17 %, 28.1 vs. 9.4 %, respectively). No pregnancies occurred when the H1 amplitude was ≥40 CPS. Logistic regression multivariate analysis found that only the median TCL H1 amplitude was associated with the occurrence of pregnancy (OR = 2.93, 95 % CI 1.065-8.08). The TCL ratio inversely correlated with the duration of embryo cryopreservation (r = −0.37).Conclusions The results indicate that thawed embryos may express oxidative processes in the cryopreservation medium, and higher oxidative levels are associated with lower implantation rates. These findings may aid in the improved selection of frozen-thawed embryos for IVF.

AIM:To find out whether serum oxidizability potential correlates with exercise test (EXT) parameters and predicts their results in chronic ischemic heart disease (IHD) patients. METHODS:Oxidizability potential was determined in a group of chronic IHD patients who underwent a symptom limited EXT upon initiation of a cardiac rehabilitation program. The thermo-chemiluminescence (TCL) assay was used to assess serum oxidizability potential. This assay is based on heat-induced oxidation of serum, leading to the formation of electronically excited species in the form of unstable carbonyls, which further decompose into stable carbonyls and light energy (low chemiluminescence). Measured photons emission is represented by a kinetic curve which is described by its amplitude and slope (= ratio). We assessed the correlations of TCL ratio with exercise duration, metabolic equivalents (METS), maximal heart rate (mHR), maximal systolic BP, > 1 mm S-T depression, diabetes, hypertension, smoking, left ventricular ejection fraction (LVEF) > or < 40%, previous myocardial infarction, and aorto-coronary bypass surgery and compared to the TCL ratio measured in a group of healthy controls. RESULTS:A high TCL ratio (%) correlated well with METS (r = 0.84), with mHR (r = 0.79) and with exercise induced S-T segment shift (r = 0.87, P < 0.05). A lower serum oxidizability potential, expressed as a low TCL ratio, thus suggestive of a previous high oxidative stress, was found in IHD patients compared to healthy controls, and, in particular, in patients with low LVEF%. The TCL ratio (%) in IHD patients was 193 ± 21, compared to 215 ± 13 in controls (P < 0.05), and was 188 ± 14.7 in patients with LVEF < 40% as compared to 200 ± 11.9 in those with LVEF > 40% (P < 0.01). A trend for lower TCL ratio (%) was found in diabetic, hypertensive, and post-coronary bypass surgery patients. A paradoxically low TCL ratio (low oxidizability potential) was observed in patients without S-T depression compared to patients with S-T depression (189 ± 22 vs 201 ± 15, P = NS), due to the fact these patients had a much lower LVEF% and a lower exercise capacity. CONCLUSION:Serum oxidizability potential is associated with EXT parameters, results, and IHD severity. TCL ratio is an "easy-to-measure marker" that might be incorporated into risk assessment and prediction in chronic IHD patients.