A comparative study on changes in hemostasis in orthotopic and auxiliary liver transplantation in pigs

We compared blood loss and hemostasis in pigs which had undergone either orthotopic liver transplantation (OLT) (group A, n=12) or auxiliary heterotopic partial liver transplantation (APLT) (group B, n=11). Blood samples were taken at regular intervals during and after the operations. In both groups, nine animals survived longer than 24 h and data from these animals were used for analysis. Median (range) intraoperative blood loss was 825 ml (250-1500 ml) in OLT and 425 ml (300-750) in APLT (P<0.01). Routine clotting times, as the activated partial thromboplastin time, prothrombin time and thrombin time, showed no major intraoperative changes in either group. Fibrinogen levels decreased in both groups, but no significant difference was found between the two groups. The only significant difference between group A and B was a more sustained increase in fibrinolytic activity after graft recirculation in group A. Post-operatively, restoration of fibrinogen, antithrombin-III and α2-antiplasmin levels was slightly faster in group B, resulting in significantly higher levels during the first day. We conclude that, in this animal model, APLT is associated with significantly lower blood loss and less severe fibrinolytic activity, than OLT. This difference might result from the lack of an anhepatic period and the reduced surgical trauma in auxiliary heterotopic liver transplantation

Identification and Validation of the Predictive Capacity of Risk Factors and Models in Liver Transplantation Over Time

Background. Outcome after liver transplantation (LT) is determined by donor, transplant and recipient risk factors. These factors may have different impact on either patient or graft survival (outcome type). In the literature, there is wide variation in the use of outcome types and points in time (short term or long term). Objective of this study is to analyze the predictive capacity of risk factors and risk models in LT and how they vary over time and per outcome type. Methods. All LTs performed in the Netherlands from January 1, 2002, to December 31, 2011, were analyzed with multivariate analyses at 3-month, 1-year, and 5-year for patient and (non-)death-censored graft survival. The predictive capacity of the investigated risk models was compared with concordance indices. Results. Recipient age, model for end-stage liver disease sodium, ventilatory support, diabetes mellitus, hepatocellular carcinoma, previous malignancy, hepatitis C virus antibody, hepatitis B virus antibody, perfusion fluid, and Eurotransplant donor risk index (ET-DRI) had significant impact on outcome (graft or patient survival) at 1 or multiple points in time. Significant factors at 3-month patient survival (recipient age, model for end-stage liver disease sodium, ventilato

IGNITION BEHAVIOR AND KINETICS OF OXIDATION OF THE REACTOR METALS, URANIUM, ZIRCONIUM, PLUTONIUM, AND THORIUM, AND BINARY ALLOYS OF EACH. A Status Report

>The importance of prevention of fires and explosions involving uranium, zircomum, plutonium, and thorium, which are of particular interest to the nuclear energy program, made imperative the study of their ignition behavior and oxidation kinetics. Methods of measurements of ignition characteristics of uranium and zirconium were developed and used to determine the effects of variables, such as surface preparation, metallurgical history, specific area (sample size), additives to the metal, and oxygen content and presence of moisture in the oxidizing gas. The study of ignition characteristics was supported by study of the effects of similar variables on the kinetics of oxidation of uranium and zirconium and binary alloys of each. The oxidation of uranium always proceeded in two linear stages over the temperature range of 125 to 295 deg C at pressures of 20, 50, 200, and 800 mm of oxygen. The temperature dependences of both stages indicate an activation energy dependent on pressure. The presence of ten additive elements in uranium metal caused only very small effects on the oxidation. The oxidation of zirconium was independent of pressure and proceeded according to a cubic rate law over the temperature range from 400 to 900 deg C, with an activation energy of 42.7 kcal per mole. For those additives soluble in zirconium at 700 deg C, the effects on the initial cubic rate law for oxidation are explained in terms of valency according to the Wagner- Hauffe Theory. For those additives insoluble in alpha zirconium, no single theory is felt to be adequate. The breakaway phenomena observed for many of the twenty alloys is explained in terms of a 15 per cent deviation of the additive ionic radius from the ionic radius of zirconium. Surveys of the literature on the oxidation of plutonium and thorium are presented in preparation for the study of their behavior. (auth

Quantitative genetic variation for post-stress cortisol and swimming performance in growth-selected and control populations of European sea bass (Dicentrarchus labrax)

Sea bass is a major species in Mediterranean aquaculture, and is now being subject to selective breeding programmes for faster growth. In terrestrial species, it was demonstrated that fast growth may be linked to a correlated degradation of fitness traits. In this experiment, we evaluated 600 young sea bass from a factorial mating of 76 sires and 13 dams. The sires were from four genetic groups, wild (W), domesticated (D), and selected for growth (2 groups, M and P). The 600 offspring were submitted to two acute confinement stress challenges at 6 weeks intervals, and plasma cortisol at one hour post stress was measured. The same fish were also submitted to two swimming challenges at a 5 days interval, where the maximum sustained swimming speed (Umax) of each fish was evaluated. Parentage was assessed by genotyping of 12 microsatellites. 554 fish had both valid parentage and phenotypes. Cortisol had a low repeatability (r = 0.30 between the two successive measurements) while repeatability was moderate for Umax (r = 0.62). However, genetic correlations between successive measurements were very high (> 0.96) for both traits, indicating that successive measurements were related to the same trait. Heritability was moderate for mean post-stress cortisol (h2 = 0.34 ± 0.09) and Umax (h2 = 0.48 ± 0.08). When Umax was expressed in m.s− 1, it was negatively correlated to cortisol (rA = − 0.48 ± 0.08) and weakly correlated to body weight (rA = 0.12 ± 0.16), but figures changed when it was expressed in Body Lengths.s− 1 (h2 = 0.55 ± 0.08, rA = − 0.10 ± 0.19 with cortisol and rA = − 0.64 ± 0.07 with body weight, respectively). Cortisol was moderately negatively correlated with body weight (rA = − 0.36 ± 0.18). The four lines did not differ for cortisol or Umax, but when Umax was expressed in BL.s− 1 it tended to be lower in the two selected lines — which were also significantly larger. However, this is likely due to a phenotypic decrease of relative Umax with increasing body size. We conclude that selection for growth and/or domestication should not impact maximum sustained swimming speed in the European sea bass, but may tend to favour animals with low cortisol responsiveness. These traits could be used to orientate functional capabilities other than productivity in sea bass.Statement of relevance: We estimate heritability of cortisol stress response and (for the first time) in European sea bass, as well as their correlations with growth. We show moderate correlations, and no correlated response to selection for growth. We also provide methods to evaluate these traits on large number of fishes. This can be useful to monitor and design breeding programmes