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AbstractBackground:Wilson’s disease (WD) can present in a fulminant form with hepatocellular dysfunction, hemolysis and multiorgan failure (Wilson’s crisis). We present a previously healthy young woman with severe WD whose WD severity score was 13. A score >11 indicates a poor chance of survival and liver transplantation will usually be recommended. Methods:Penicillamine and acetylcysteine were initially administered, but the patient deteriorated further, and extracorporeal liver support with the Prometheus® FPSA (fractionated plasma separation and adsorption) system was initiated. The patient was treated 6 h daily during 3 consecutive days. Results:Severe hemolysis was reduced to low-grade hemolysis, with no further need for transfusions. The mental state improved and after 4 months practically all biochemical markers were normalized. Conclusions:This is the first report of FPSA albumin dialysis of a patient with Wilson’s crisis and the first report in which a patient with a WD score >11 survived without transplantation.Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

AbstractIn an attempt to examine the dynamic inter-relationship among wood density and fibre traits [tracheid length and microfibril angle (MFA)] in lodgepole pine (Pinus contorta), 60 trees were sampled in three age classes from four sites in central British Columbia. Breast height discs were taken and relative wood density was measured along two radii. Tracheid length was assessed on isolated 5-year increments from pith to bark at breast height for each tree. MFA was determined every 50 μm and the 5-mm composite intervals from pith to bark per disc at breast height were used in the analysis. Segmented regression was employed to identify the “juvenile to mature wood” transition point, which revealed transition ages of 31, 18 and 15 for wood density, fibre length and MFA, respectively. These traits were related to primary growth, expressed as area increment, ring width, percent earlywood and height increment during the juvenile wood phase. Comparisons of wood and fibre traits showed a higher congruence between the time of transitions for fibre length and MFA (Pearson correlation coefficient 0.52) than that between fibre length and wood density (0.07), and MFA and wood density (0.16). The cessation of early rapid radial increment growth terminated before wood and fibre transitions to mature wood occurred. Fibre length was significantly, but not strongly, related to ring width and percent earlywood (0.35 for both). The duration of juvenile fibre production was not significantly related to height growth. [ABSTRACT FROM AUTHOR]

Abstract  Hepatic encephalopathy is a severe neuropathological condition arising secondary to liver failure. The pathogenesis is not well understood; however, hyperammonemia is considered to be one causative factor. Hyperammonemia has been suggested to inhibit tricarboxylic acid (TCA) cycle activity, thus affecting energy metabolism. Furthermore, it has been suggested that catabolism of the branched-chain amino acid isoleucine may help curb the effect of hyperammonemia by by-passing the TCA cycle block as well as providing the carbon skeleton for glutamate and glutamine synthesis thus fixating ammonia. Here we present novel results describing [U-13C]isoleucine metabolism in muscle and brain analyzed by mass spectrometry in bile duct ligated rats, a model of chronic hepatic encephalopathy, and discuss them in relation to previously published results from neural cell cultures. The metabolism of [U-13C]isoleucine in muscle tissue was about five times higher than that in the brain which, in turn, was lower than in corresponding cell cultures. However, synthesis of glutamate and glutamine was supported by catabolism of isoleucine. In rat brain, differential labeling patterns in glutamate and glutamine suggest that isoleucine may primarily be metabolized in the astrocytic compartment which is in accordance with previous findings in neural cell cultures. Lastly, in rat brain the labeling patterns of glutamate, aspartate and GABA do not suggest any significant inhibition by ammonia of TCA cycle activity which corresponds well to findings in neural cell cultures. Branched-chain amino acids including isoleucine are used for treating hepatic encephalopathy and the present findings shed light on the possible mechanism involved. The low turn-over of isoleucine in rat brain suggests that this amino acid does not serve the role of providing metabolites pertinent to TCA cycle function and hence energy formation as well as the necessary carbon skeleton for subsequent ammonia fixation in hyperammonemia. The higher metabolism of isoleucine in muscle could, however, contribute to ammonia fixation and thus likely be of value in the treatment of hepatic encephalopathy. [ABSTRACT FROM AUTHOR]

This paper demonstrates that the impact of nanosecond pulsed dielectric barrier discharge (ns-DBD) actuators on the structure of the boundary layer can be investigated using quantitative convective heat transfer measurements. For the experiments, the flow over a flat plate with a C4 leading edge thickness distribution was examined at low speed incompressible flow (6.6–11.5 m s−1). An ns-DBD plasma actuator was mounted 5 mm downstream of the leading edge and several experiments were conducted giving particular emphasis on the effect of actuation frequency and the freestream velocity. Local heat transfer distributions were measured using the transient liquid crystal technique with and without plasma activated. As a result, any effect of plasma on the structure of the boundary layer is interpreted by local heat transfer coefficient distributions which are compared with laminar and turbulent boundary layer correlations. The heat transfer results, which are also confirmed by hot-wire measurements, show the considerable effect of the actuation frequency on the location of the transition point elucidating that liquid crystal thermography is a promising method for investigating plasma-flow interactions very close to the wall. Additionally, the hot-wire measurements indicate possible velocity oscillations in the near wall flow due to plasma activation. [ABSTRACT FROM AUTHOR]