Biodegradative mechanism of the brown rot basidiomycete Gloeophyllum trabeum: evidence for an extracellular hydroquinone-driven fenton reaction

AbstractWe have identified key components of the extracellular oxidative system that the brown rot fungus Gloeophyllum trabeum uses to degrade a recalcitrant polymer, polyethylene glycol, via hydrogen abstraction reactions. G. trabeum produced an extracellular metabolite, 2,5-dimethoxy-1,4-benzoquinone, and reduced it to 2,5-dimethoxyhydroquinone. In the presence of 2,5-dimethoxy-1,4-benzoquinone, the fungus also reduced extracellular Fe3+ to Fe2+ and produced extracellular H2O2. Fe3+ reduction and H2O2 formation both resulted from a direct, non-enzymatic reaction between 2,5-dimethoxyhydroquinone and Fe3+. polyethylene glycol depolymerization by G. trabeum required both 2,5-dimethoxy-1,4-benzoquinone and Fe3+ and was completely inhibited by catalase. These results provide evidence that G. trabeum uses a hydroquinone-driven Fenton reaction to cleave polyethylene glycol. We propose that similar reactions account for the ability of G. trabeum to attack lignocellulose

Craniofacial morphology in unilateral hemifacial microsomia

Hemifacial microsomia (HFM) is a complex three-dimensional congenital condition that is characterized by mandibular hypoplasia and unilateral or bilateral microtia; although, other facial structures may be affected. Little is known about craniofacial growth and morphology in patients with HFM; therefore, we examined 75 HFM patients by means of a cephalometric analysis in a longitudinal study on serial lateral cephalograms. We hypothesized that the growth of several facial structures on both sides of HFM patients would be different compared to Dutch controls. We determined patients with HEM had more retruded mandibles and maxillae and a more vertical morphology compared to the reference population. In addition, there was a more retruded and vertical pattern on the affected side compared to the unaffected side and in patients with a severe condition compared to those with a mild condition. 'Mild' HFM patients were more similar to the Dutch reference population than the 'severe' HFM patients. Individual HFM growth curves showed very high inter-variability, further strengthening the need for individualized treatment plans that consider all three dimensions and the severity of the condition. (C) 2012 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved

Changes of mandibular ramal height, during growth in unilateral hemifacial microsomia patients and unaffected controls

The aim of this study was to design mandibular ramal height growth curves for patients with HFM and compare those with the curves for a Dutch reference population. Two hundred fifty-one pre-operative orthopantomograms (OPTs) from 84 patients with unilateral HFM were used in conjunction with a control set of 2260 OPTs from 329 healthy individuals from the Nijmegen Growth Study (NGS) to determine mandibular ramal distances. For grades I/IIa and IIb/III, and for both sides, growth curves were constructed for mandibular ramal height with a linear curve-fitting procedure. This procedure revealed a significant difference between HFM patients and the NGS control group (p < 0.001); both in the mild and severe group mandibular ramal height differed significantly between the affected and non-affected side (p < 0.001). Growth was similar between HFM patients and the NGS control group. HFM patients therefore start with a smaller mandible and end with a smaller mandible, but experience growth similar to the Dutch normal population. These growth curves may aid the timing and determination of the combined surgical orthodontic treatment plan for HFM patients. (C) 2012 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved

Physical inactivity:A risk factor and target for intervention in renal care

Regular physical activity is associated with an increased quality of life and reduced morbidity and mortality in the general population and in patients with chronic kidney disease (CKD). Physical activity, cardiorespiratory fitness, and muscle mass decrease even in the early stages of CKD, and continue to decrease with disease progression; notably, full recovery is generally not achieved with transplantation. The combined effects of uraemia and physical inactivity drive the loss of muscle mass. Regular physical activity benefits cardiometabolic, neuromuscular and cognitive function across all stages of CKD, and therefore provides an approach to address the multimorbidity of the CKD population. Interestingly, maintenance of muscle health is associated with renoprotective effects. Despite evidence of its benefits, physical activity and exercise management are not routinely addressed in the care of these patients. Although studies defining the optimum frequency, duration and intensity of physical activity are lacking, evidence from related fields can guide practical approaches to the care of patients with renal disease. Optimization of metabolic and nutritional status alongside promotion of physical activity is recommended. Behavioural approaches are now recognized as crucial in helping patients to adopt lifestyle changes and might prove valuable in integrating physical activity into renal care