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Friedreich's ataxia (FRDA) is a hereditary cardiodegenerative and neurodegenerative disease that affects 1 in 50 000 Americans. FRDA arises from either a cellular inability to produce sufficient quantities or the production of a nonfunctional form of the protein frataxin, a key molecule associated with mitochondrial iron–sulfur cluster biosynthesis. Within the mitochondrial iron–sulfur cluster (ISC) assembly pathway, frataxin serves as an allosteric regulator for cysteine desulfurase, the enzyme that provides sulfur for [2Fe–2S] cluster assembly. Frataxin is a known iron-binding protein and is also linked to the delivery of ferrous ions to the scaffold protein, the ISC molecule responsible for the direct assembly of [2Fe–2S] clusters. The goal of this report is to provide structural details of the Drosophila melanogaster frataxin ortholog (Dfh), using both X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy, in order to provide the foundational insight needed to understand the structure–function correlation of the protein. Additionally, NMR iron(II) titrations were used to provide metal contacts on the protein to better understand how it binds iron and aids its delivery to the ISC scaffold protein. Here, the structural and functional similarities of Dfh to its orthologs are also outlined. Structural data show that bacterial, yeast, human and Drosophila frataxins are structurally similar, apart from a structured C-terminus in Dfh that is likely to aid in protein stability. The iron-binding location on helix 1 and strand 1 of Dfh is also conserved across orthologs.

Mitochondrial [2Fe-2S] cluster biosynthesis is driven by the coordinated activities of the Iron-Sulfur Cluster (ISC) pathway protein machinery. Within the ISC machinery, the protein that provides a structural scaffold on which [2Fe-2S] clusters are assembled is the ISCU protein in humans; this protein is referred to as the "Scaffold" protein. Truncation of the C-terminal portion of ISCU causes the fatal disease "ISCU Myopathy", which exhibits phenotypes of reduced Fe-S cluster assembly in cells. In this report, the yeast ISCU ortholog "Isu1" has been characterized to gain a better understanding of the role of the scaffold protein in relation to [2Fe-2S] assembly and ISCU Myopathy. Here we explored the biophysical characteristics of the C-terminal region of Isu1, the segment of the protein that is truncated on the human ortholog during the disease ISCU Myopathy. We characterized the role of this region in relation to iron binding, protein stability, assembly of the ISC multiprotein complex required to accomplish Fe-S cluster assembly, and finally on overall cell viability. We determined the Isu1 C-terminus is essential for the completion of the Fe-S cluster assembly but serves a function independent of protein iron binding.

Introduction Pain which persists after thoracotomy is well recognized, and activation of the N-methyl-d-aspartate (NMDA) receptor could be a contributing factor. This study sought to establish whether ketamine given peri-operatively could reduce persistent post-surgical pain. Trial design Double-blind, randomized, placebo-controlled trial comparing low-dose intravenous ketamine and saline placebo. Methods Seventy patients undergoing thoracotomy were randomized to receive either intravenous ketamine (0.1 mg kg-1 hr-1 ) or saline placebo for 96 hr, starting 10 min prior to surgery. A bolus dose of 0.1 mg/kg of ketamine/placebo was given prior to starting the infusion. Post-operative analgesia consisted of either an epidural infusion or patient-controlled analgesia (PCA), +/- a paravertebral infusion of local anaesthetic. Pain scores and opioid consumption were collected at 24 and 48 hr after surgery. Patients completed numeric pain scores (NPS), modified Brief Pain Inventory (BPI), the short form Leeds Assessment of Neuropathic Symptoms and Signs (S-Lanss) at baseline, 6 weeks, 3, 6 and 12 months after surgery. Results There were no significant differences in post-operative pain, except the ketamine group reported less pain at rest 48 hr after surgery (p = 0.03). The ketamine group requested significantly less morphine via PCA in the first 24 hr (p = 0.03). There were no differences in pain measures or opioid consumption at 6 weeks, 3, 6 or 12 months. Patients in the ketamine group were more lightheaded (p = 0.02) and experienced more vivid dreams (p = 0.001). Conclusions Ketamine reduced opioid consumption compared to placebo after surgery, but we were unable to detect any differences in persistent post-surgical pain between the groups. Significance This study adds to the growing body of evidence advocating the use of ketamine to reduce opioid consumption. No previous studies of peri-operative ketamine have followed patients for a year after thoracotomy. This study found no reduction in persistent post-surgical pain.

Research suggests that active and discussion driven dialogic approaches to teaching are more effective than passive learning methods. One way to encourage more participatory learning is through the adoption of simple, freely available audience response systems which allow instant and inclusive staff-student dialogue during teaching sessions. Existing literature is largely limited to exploring the impact of basic approaches to audience participation, using handheld cards or simple ‘clickers’. Limited research exists looking at the impact and best use of a new generation of online audience response systems which have significantly expanded functionality. This article will explore the impact of one of the most agile platforms, Mentimeter. It outlines impact on student satisfaction, enjoyment, voice and learning within small and large group settings across multiple disciplines drawing on 204 student survey responses. It also explores staff experiences and reflections on the key practical and pedagogical thinking required in order to optimise the use of this platform in Higher Education. The research responds to a need within the sector to react to rapid advances in teaching and learning technology, to provide evidence of impact for lecturers looking to improve student learning environments, whilst being cognisant of the underlying pedagogy supportive of new practices.

Osteosarcoma (OS) is a malignant bone tumor predominantly affecting children and adolescents. OS has a 60% survival rate with current treatments; hence, there is a need to identify novel adjuncts to chemotherapeutic regimens. In this pilot study, we investigated the dose-response to 1α,25-dihdroxyvitamin D3 (1,α 25(OH)2D3) and 25-hydroxyvitamin D3 (25(OH)D3) by human OS cell lines, SaOS-2, and 143B. We hypothesized that 1,α 25(OH)2D3 and 25(OH)D3 would stimulate differentiation and induce apoptosis in OS cells in a dose-dependent manner. Human OS cell lines, SaOS-2, and 143B, were treated with 1,α 25(OH)2D3 or 25(OH)D3 or an ethanol control, respectively, at concentrations ranging from 1 to 1,000 nM. Ki67 (a marker of cellular proliferation) immunocytochemistry revealed no significant changes in the expression of Ki-67 or MIB-1 in 1α,25(OH)2D3 or 25(OH)D3 treated SaOS-2 or 143B cells. Both control and 1α,25(OH)2D3 treated SaOS-2 and 143B cells expressed vitamin D receptor (VDR). Markers of osteoblastic differentiation in 143B cells and SaOS-2 cells were induced by both 25(OH)D3 and 1α,25(OH)2D, and evident by increases in alkaline phosphatase (ALP) activity, osteocalcin (OCN) mRNA expression, and mineralization of extra-cellular matrix (ECM) by alizarin red staining. An increasing trend in apoptosis in response to 25(OH)D3, in both SaOS-2 and 143B cells was detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining. With 1α,25(OH)2D3 treatment, apoptosis was evident at higher concentrations only. These preliminary findings suggest that OS cells express VDR and respond to 25(OH)D3 and 1α,25(OH)2D3 by undergoing differentiation and apoptosis. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:831–844, 2012

Bird species in the avian genus Pitohui contain potent neurotoxic alkaloids that may be used for defense. The genus comprises multiple species that are endemic to New Guinea and were presumed to belong to the family Pachycephalidae or Colluricinclidae, within the core corvoidea, an ancient Australasian radiation of crow-like birds. In order to understand the evolution of toxicity within the genus Pitohui, we sequenced three mitochondrial and two nuclear gene segments and reconstructed a phylogeny of the genus Pitohui and its putative relatives. We show that the genus Pitohui is polyphyletic, and consists of five different lineages. Using Bayesian ancestral state reconstruction, we estimate that toxicity likely evolved multiple times within this group. Furthermore, because the morphological and behavioral similarity among these poisonous birds appears to have evolved convergently, we hypothesize that this may be a possible example of Müllerian mimicry in birds. The Morningbird of Palau, Micronesia, that has often been included in the genus Pitohui, actually belongs in the genus Pachycephala and offers an intriguing case of pronounced evolution on a remote oceanic island.

Multiatlas methods have been successful for brain segmentation, but their application to smaller anatomies remains relatively unexplored. We evaluate seven statistical and voting-based label fusion algorithms (and six additional variants) to segment the optic nerves, eye globes, and chiasm. For nonlocal simultaneous truth and performance level estimation (STAPLE), we evaluate different intensity similarity measures (including mean square difference, locally normalized cross-correlation, and a hybrid approach). Each algorithm is evaluated in terms of the Dice overlap and symmetric surface distance metrics. Finally, we evaluate refinement of label fusion results using a learning-based correction method for consistent bias correction and Markov random field regularization. The multiatlas labeling pipelines were evaluated on a cohort of 35 subjects including both healthy controls and patients. Across all three structures, nonlocal spatial STAPLE (NLSS) with a mixed weighting type provided the most consistent results; for the optic nerve NLSS resulted in a median Dice similarity coefficient of 0.81, mean surface distance of 0.41 mm, and Hausdorff distance 2.18 mm for the optic nerves. Joint label fusion resulted in slightly superior median performance for the optic nerves (0.82, 0.39 mm, and 2.15 mm), but slightly worse on the globes. The fully automated multiatlas labeling approach provides robust segmentations of orbital structures on magnetic resonance imaging even in patients for whom significant atrophy (optic nerve head drusen) or inflammation (multiple sclerosis) is present.

Introduction: Frequent dissociation between clinical severity and angiographic grading of moyamoya supports a role for alternative tissue-level hemodynamic measures. Here, angiography is complemented with noninvasive MRI measurements of parenchymal impairment to assess changes in cerebrovascular reactivity (CVR) after extracranial-intracranial bypass in moyamoya. Hypothesis: CVR is regionally impaired pre-operatively, yet increases after surgery. This can be visualized noninvasively by assessing blood oxygenation level-dependent (BOLD) MRI changes with safe, mildly hypercarbic gas. Methods: Using a block MRI paradigm, carbogen (5% CO 2 ; 95% O 2 3 min) was interleaved with atmospheric air (2 ; 3 min) administration during BOLD MRI in intracranial stenosis patients (n=70), a subset of which (n=9; age=35.7+/-10.8; 7F/2M) underwent indirect (n=8) or direct (n=1) revascularization for moyamoya. Five patients had both pre-operative and post-operative hemodynamic imaging, with post-operative scans performed after 7.3+/-4.1 months. CVR, calculated as a z-statistic in response to hypercarbia vs. atmospheric air, was compared (two-tailed t-test) for each patient between the two time points to correlate CVR changes with surgery. Results: Fig. 1 shows BOLD MRI on a patient scanned before and 2 years after right-sided indirect bypass, with significant (t=79.29, p Conclusions: CVR-weighted hemodynamic MRI can be implemented into routine clinical protocols, corresponds well with revascularization response, and has potential as a noninvasive complement to angiography for serial monitoring of moyamoya patients.

The title compounds are hydrothermally synthesized from aqueous mixtures of LnVO4 (Ln: Y, Sc, Dy, Ho, Lu, Tm, Yb) and K2CO3 (autoclave, 560 °C, 6 d).

A new series of materials of the glaserite family with the general formula K(3)RE(VO(4))(2)(RE = Sc, Y, Dy, Ho, Er, Tm, Yb, and Lu) have been hydrothermally synthesized using 10 M K(2)CO(3) at 560 °C and characterized by single crystal X-ray diffraction (XRD), powder XRD, differential thermal analysis/thermogravimetric analysis (DTA/TGA), energy-dispersion X-ray (EDX), Raman, infrared, and absorption spectroscopy. All the compounds crystallize in the trigonal P3̅m1 space group (No. 164), and their structures contain VO(4) tetrahedra, REO(6) octahedra, and two different K(1)O(10) and K(2)O(12) polyhedra. The spectroscopic properties of Nd(3+), Yb(3+), or Er(3+) doped K(3)RE(VO(4))(2) (RE = Y or Lu) are also reported, and the results obtained show that these compounds have promising potential as new laser host materials.

Osteosarcoma (OS) is a malignant bone tumor predominantly affecting children and adolescents. OS has a 60% survival rate with current treatments; hence, there is a need to identify novel adjuncts to chemotherapeutic regimens. In this pilot study, we investigated the dose-response to 1α,25-dihdroxyvitamin D(3) (1,α 25(OH)(2) D(3)) and 25-hydroxyvitamin D(3) (25(OH)D(3)) by human OS cell lines, SaOS-2, and 143B. We hypothesized that 1,α 25(OH)(2) D(3) and 25(OH)D(3) would stimulate differentiation and induce apoptosis in OS cells in a dose-dependent manner. Human OS cell lines, SaOS-2, and 143B, were treated with 1,α 25(OH)(2)D(3) or 25(OH)D(3) or an ethanol control, respectively, at concentrations ranging from 1 to 1,000 nM. Ki67 (a marker of cellular proliferation) immunocytochemistry revealed no significant changes in the expression of Ki-67 or MIB-1 in 1α,25(OH)(2)D(3) or 25(OH)D(3) treated SaOS-2 or 143B cells. Both control and 1α,25(OH)(2) D(3) treated SaOS-2 and 143B cells expressed vitamin D receptor (VDR). Markers of osteoblastic differentiation in 143B cells and SaOS-2 cells were induced by both 25(OH)D(3) and 1α,25(OH)(2) D, and evident by increases in alkaline phosphatase (ALP) activity, osteocalcin (OCN) mRNA expression, and mineralization of extra-cellular matrix (ECM) by alizarin red staining. An increasing trend in apoptosis in response to 25(OH)D(3), in both SaOS-2 and 143B cells was detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining. With 1α,25(OH)(2)D(3) treatment, apoptosis was evident at higher concentrations only. These preliminary findings suggest that OS cells express VDR and respond to 25(OH)D(3) and 1α,25(OH)(2)D(3) by undergoing differentiation and apoptosis.

The presence of litter and the availability of nitrogen supply were manipulated in experimental field-grown populations of the annual Arabidopsis thaliana (Cruciferae). Arabidopsis typically has two generations a year. Spring-germinating plants (G1) set seed and die. Litter from this generation had an immediate effect on plants of the second generation (G2) germinating during late summer. Litter from G2 broke down over winter, and had a less direct impact on the next spring generation (G3). A two phase model is proposed, whereby litter from G1 plants acted directly to spread reproductive output of G2 plants over many small individuals, with no effect on overall capsule production. Nitrogen depletion by G1 plants did not affect the productivity of the second generation (G2) which germinated in the same summer (...)