Erythroderma (exfoliative dermatitis). Part 2: energy homeostasis and dietetic management strategies

Erythroderma (exfoliative dermatitis) is associated with important metabolic changes that include an enhancement in energy expenditure. The key components to total energy expenditure (TEE) include basal metabolic rate (~68% of TEE), physical activity (~22% of TEE) and thermic effect of food (~10% of TEE). In the erythrodermic state, there are likely multiple contributors to the increase in basal metabolic rate, such as 'caloric drain' resulting from increased evaporation of water from enhanced transepidermal water loss, increased activity of the cardiovascular system (including high-output cardiac failure), increased nonshivering thermogenesis and hormonal changes such as hypercortisolaemia. A change in the patient's level of physical activity and appetite as a result of ill health status may further impact on their TEE and energy consumption. In Part 2 of this two-part concise review, we explore the key constituents of energy homeostasis and the potential mechanisms influencing energy homeostasis in erythroderma, and suggest much-needed dietetic management strategies for this important condition.

Erythroderma (exfoliative dermatitis). Part 1: underlying causes, clinical presentation and pathogenesis

Erythroderma (exfoliative dermatitis), first described by Von Hebra in 1868, manifests as a cutaneous inflammatory state, with associated skin barrier and metabolic dysfunctions. The annual incidence of erythroderma is estimated to be 1-2 per 100 000 population in Europe with a male preponderance. Erythroderma may present at birth, or may develop acutely or insidiously (due to progression of an underlying primary pathology, including malignancy). Although there is a broad range of diseases that associate with erythroderma, the vast majority of cases result from pre-existing and chronic dermatoses. In the first part of this two-part concise review, we explore the underlying causes, clinical presentation, pathogenesis and investigation of erythroderma, and suggest potential treatment targets for erythroderma with unknown causes.

Uptake and intracellular stability of glycosylphosphatidylinositol-specific phospholipase D in neuroblastoma cells

Glycosylphosphatidylinositol-specific phospholipase D from mammalian serum has been described to be relatively stable towards the action of proteases in vitro, and it has been speculated that the enzyme may only be active on glycosylphosphatidylinositol-anchored substrates after its proteolytic processing in an intracellular compartment following uptake from body fluids. To test this hypothesis, we studied the possible uptake and intracellular processing of purified glycosylphosphatidylinositol-specific phospholipase D into the mouse neuroblastoma cell line N2A. We found that after incubation of neuroblastoma cells with glycosylphosphatidylinositol-specific phospholipase D at 37 degrees C the amount of cell-associated glycosylphosphatidylinositol-specific phospholipase D activity increased in a concentration- and time-dependent way. A similar uptake was also observed with 125I-labeled intact and trypsin-treated form of glycosylphosphatidylinositol-specific phospholipase D. We found that the incorporated radiolabeled proteins were processed intracellularly to distinct low molecular mass products, and that this process was in part inhibited by the presence of chloroquine during incubation.

Subcellular distribution of glycosylphosphatidylinositol-specific phospholipase D in rat liver

Glycosylphosphatidylinositol (GPI)-hydrolysing enzymes have been described in many mammalian tissues and body fluids; however, their site(s) of action and in vivo functions have remained unclear. In order to identify a possible intracellular site of GPI hydrolysis, we studied the subcellular distribution of GPI-hydrolysing activity in rat liver. We found that purified fractions from rat liver hydrolysed the GPI moieties of two GPI-anchored proteins with the specificity of a phospholipase D. This GPI-specific phospholipase D (GPI-PLD) activity was found to be highly enriched in a lysosomal fraction and showed a similar intracellular distribution to that of typical lysosomal enzymes. Our results indicate that lysosomes may represent a possible intracellular site of GPI-PLD action.

Clearance of atrazine in soil describing xenobiotic behavior

The primary aim of this study was to evaluate the "clearance concept" as a tool for describing the behavior of xenobiotic movement into and through soils. As an example, degradation of 2-chloro-4-ethylamino-6-isopropylamino-s-triazine (atrazine) with the formation of metabolites 2-chloro-6-isopropylamino-s-triazine (desethylatrazine) and 2-chloro-4-ethylamino-s-triazine (desisopropylatrazine) was investigated. Atrazine was sprayed post-emergently in doses of 0.125 or 0.5 g active ingredient/m(2) each on four test plots. Soil type was a sandy-loam, on which corn (Zea mays L.) was cultivated. Soil samples were taken as cores of 0.2 m depth 0, 1, 2, 4, 8, 12, 16 and 20 weeks after application of atrazine, and analyzed by HPLC. Soil concentrations of atrazine were highly correlated (r=0.993, p< 0.001) between the two applications of 0.125 g/m(2) and 0.5 g/m(2). Up to 50% of the atrazine was measured as metabolites during the whole vegetation period. Clearance of atrazine from soil was calculated as the total load of atrazine divided by the area under the soil atrazine concentration time curve. Soil atrazine clearance was calculated as 5.13 +/- SD 1.10 and 5.17 +/- SD 1.02 liter of soil per day for doses of 0.125 g/m(2) and 0.5 g/m(2), respectively (from a "soil unit" of 1 × 1 × 0.2 meter). The clearance concept might be a tool for risk assessment of xenobiotics.

The Crystal Structure of Acifluorfen {5-[2-Chloro-4-(trifluoromethyl)-phenoxy]-2-nitrobenzoic Acid}

The crystal structure of the herbicide acifluorfen (5-[(2-chloro-4-trifluoromethyl)]phenoxy-2- nitrobenzoic acid] has been determined by X-ray diffraction and refined to a residual of 0.051for 1124 observed reflections. Crystals are monoclinic, space group C2/c with cell dimensions a 26.848(7), b 8 .O29(2), c 19 .Ol4(6) �, ,R l34.72(2)� and Z 8. The molecules form centrosymmetric hydrogen-bonded cyclic dimers [O---0, 2.637(7) �] with the carboxylic acid group and the phenoxy group synclinally related to the first phenyl ring while the nitro substituent isessentially coplanar with the ring.