595 research outputs found

    Self-concept of gifted children aged 9 to 13 years old

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    Ninety-four gifted children and 200 nongifted children (aged 9 to 13 years old) were involved in the present study. Their self-concept was assessed by the Revised Song-Hattie Self-Concept Inventory (Zhou & He, 1996). Academic self-concepts pertaining to abilities, school achievements, and grade concepts and nonacademic self-concepts pertaining to family, peers, body, and self-confidence concepts, as well as self-concept in general, were considered in the present study. The findings indicated that the development of self-concept in gifted children was different from that of nongifted children.Specifically, the self-concept scores in general of nongifted children increased from 11 to 13 years old, while those of gifted children decreased for the same age period. Both academic and nonacademic self-concepts are discussed in the present study

    Neuropilin 1 sequestration by neuropathogenic mutant glycyl-tRNA synthetase is permissive to vascular homeostasis

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    The mechanism by which dominantly inherited mutations in the housekeeping gene GARS, which encodes glycyl-tRNA synthetase (GlyRS), mediate selective peripheral nerve toxicity resulting in Charcot-Marie-Tooth disease type 2D (CMT2D) is still largely unresolved. The transmembrane receptor protein neuropilin 1 (Nrp1) was recently identifed as an aberrant extracellular binding partner of mutant GlyRS. Formation of the Nrp1/mutant GlyRS complex antagonises Nrp1 interaction with one of its main natural ligands, vascular endothelial growth factor-A (VEGF-A), contributing to neurodegeneration. However, reduced extracellular binding of VEGF-A to Nrp1 is known to disrupt post-natal blood vessel development and growth. We therefore analysed the vascular system at early and late symptomatic time points in CMT2D mouse muscles, retina, and sciatic nerve, as well as in embryonic hindbrain. Mutant tissues show no diference in blood vessel diameter, density/growth, and branching from embryonic development to three months, spanning the duration over which numerous sensory and neuromuscular phenotypes manifest. Our fndings indicate that mutant GlyRS-mediated disruption of Nrp1/VEGF-A signalling is permissive to maturation and maintenance of the vasculature in CMT2D mice

    Determination and Distribution Study of Pogostone in Rat Tissues by Ultra-Fast Liquid Chromatography

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    Purpose: To develop and validate a rapid, sensitive and reliable ultra-fast liquid chromatography (UFLC) method with photodiode array (PDA) detection for the determination of pogostone (PO) in rat tissues using honokiol as internal standard (IS).Methods: Rats were randomly divided into two groups (intravenous administration group and oral administration group) and given of a single dose of 10 mg/kg PO by intravenous administration and oral administration, respectively. After intravenous injection, the rats were sacrificed at 15, 60 and 360 min, while rats, after oral administration, were euthanasized at 30, 90 and 360 min, respectively. For the analysis of the preparation, optimal chromatographic conditions were determined using Acquity UPLC BEH C18 column with acetonitrile-water containing 0.1 % formic acid (55:45, v/v) as the mobile phase, at a flow rate of 400 μL/min. UV detection wavelength was set at 310 nm with temperature maintained at 30 °C.Results: Good linear relationship of calibration curve (r > 0.9984) was achieved over the range of 0.1 - 40 μg/mL for all the tissue samples. The limit of quantification (LOQ) and limit of detection (LOD) were 0.1 and 0.05 μg/mL, respectively. This method proved to have good precision, accuracy, stability, extraction recovery and matrix effect for tissue distribution studies of PO in rats.Conclusion: The developed method is suitable for tissue distribution studies in rats following intravenous and oral administration of PO at a dose of 10 mg/kg.Keywords: Ultra-fast liquid chromatography, Tissue distribution, Pogostone, Honokiol, Rat

    Neural mechanisms of 1-back working memory in intellectually gifted children

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    To investigate the neural mechanisms underlying intellectually gifted children, electroencephalograms (EEG) were recorded while 13 intellectually gifted children and 13 average children accomplished a 1-back working memory task. The results showed that intellectually gifted children elicited significantly shorter P3 latency than their intellectually average peers. These results support the neural efficiency theory that intellectually gifted individual can use their brain more efficiently

    Trk receptor signaling and sensory neuron fate are perturbed in human neuropathy caused by Gars mutations

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    Charcot-Marie-Tooth disease type 2D (CMT2D) is a peripheral nerve disorder caused by dominant, toxic, gain-of-function mutations in the widely expressed, housekeeping gene, GARS. The mechanisms underlying selective nerve pathology in CMT2D remain unresolved, as does the cause of the mild-to-moderate sensory involvement that distinguishes CMT2D from the allelic disorder distal spinal muscular atrophy type V. To elucidate the mechanism responsible for the underlying afferent nerve pathology, we examined the sensory nervous system of CMT2D mice. We show that the equilibrium between functional subtypes of sensory neuron in dorsal root ganglia is distorted by Gars mutations, leading to sensory defects in peripheral tissues and correlating with overall disease severity. CMT2D mice display changes in sensory behaviour concordant with the afferent imbalance, which is present at birth and non-progressive, indicating that sensory neuron identity is pre-natally perturbed and that a critical developmental insult is key to the afferent pathology. Through in vitro experiments, mutant, but not wild-type, GlyRS was shown to aberrantly interact with the Trk receptors and cause mis-activation of Trk signalling, which is essential for sensory neuron differentiation and development. Together, this work suggests that both neurodevelopmental and neurodegenerative mechanisms contribute to CMT2D pathogenesis, and thus has profound implications for the timing of future therapeutic treatments

    The World Hip Trauma Evaluation Study 3 HEMIARTHROPLASTY EVALUATION BY MULTICENTRE INVESTIGATION - WHiTE 3: HEMI - AN ABRIDGED PROTOCOL

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    Approximately half of all hip fractures are displaced intracapsular fractures. The standard treatment for these fractures is either hemiarthroplasty or total hip arthroplasty. The recent National Institute for Health and Care Excellence (NICE) guidance on hip fracture management recommends the use of 'proven' cemented stem arthroplasty with an Orthopaedic Device Evaluation Panel (ODEP) rating of at least 3B (97% survival at three years). The Thompsons prosthesis is currently lacking an ODEP rating despite over 50 years of clinical use, likely due to the paucity of implant survival data. Nationally, adherence to these guidelines is varied as there is debate as to which prosthesis optimises patient outcomes.This study design is a multi-centre, multi-surgeon, parallel, two arm, standard-of-care pragmatic randomised controlled trial. It will be embedded within the WHiTE Comprehensive Cohort Study (ISRCTN63982700). The main analysis is a two-way equivalence comparison between Hemi-Thompson and Hemi-Exeter polished taper with Unitrax head. Secondary outcomes will include radiological leg length discrepancy measured as per Bidwai and Willett, mortality, re-operation rate and indication for re-operation, length of index hospital stay and revision at four months. This study will be supplemented by the NHFD (National Hip Fracture Database) dataset.Evidence on the optimum choice of prosthesis for hemiarthroplasty of the hip is lacking. National guidance is currently based on expert opinion rather than empirical evidence. The incidence of hip fracture is likely to continue to increase and providing high quality evidence on the optimumCite this article: A. L. Sims. The World Hip Trauma Evaluation Study 3: Hemiarthroplasty Evaluation by Multicentre Investigation - WHITE 3: HEMI - An Abridged Protocol. Bone Joint Res 2016;5:18-25. doi: 10.1302/2046-3758.51.2000473

    Expression of CXCL10 is associated with response to radiotherapy and overall survival in squamous cell carcinoma of the tongue

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    Five-year survival for patients with oral cancer has been disappointingly stable during the last decades, creating a demand for new biomarkers and treatment targets. Lately, much focus has been set on immunomodulation as a possible treatment or an adjuvant increasing sensitivity to conventional treatments. The objective of this study was to evaluate the prognostic importance of response to radiotherapy in tongue carcinoma patients as well as the expression of the CXC-chemokines in correlation to radiation response in the same group of tumours. Thirty-eight patients with tongue carcinoma that had received radiotherapy followed by surgery were included. The prognostic impact of pathological response to radiotherapy, N-status, T-stage, age and gender was evaluated using Cox's regression models, Kaplan-Meier survival curves and chi-square test. The expression of 23 CXC-chemokine ligands and their receptors were evaluated in all patients using microarray and qPCR and correlated with response to treatment using logistic regression. Pathological response to radiotherapy was independently associated to overall survival with a 2-year survival probability of 81 % for patients showing a complete pathological response, while patients with a non-complete response only had a probability of 42 % to survive for 2 years (p = 0.016). The expression of one CXC-chemokine, CXCL10, was significantly associated with response to radiotherapy and the group of patients with the highest CXCL10 expression responded, especially poorly (p = 0.01). CXCL10 is a potential marker for response to radiotherapy and overall survival in patients with squamous cell carcinoma of the tongue

    Silicon Mie Resonators for Highly Directional Light Emission from monolayer MoS2

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    Controlling light emission from quantum emitters has important applications ranging from solid-state lighting and displays to nanoscale single-photon sources. Optical antennas have emerged as promising tools to achieve such control right at the location of the emitter, without the need for bulky, external optics. Semiconductor nanoantennas are particularly practical for this purpose because simple geometries, such as wires and spheres, support multiple, degenerate optical resonances. Here, we start by modifying Mie scattering theory developed for plane wave illumination to describe scattering of dipole emission. We then use this theory and experiments to demonstrate several pathways to achieve control over the directionality, polarization state, and spectral emission that rely on a coherent coupling of an emitting dipole to optical resonances of a Si nanowire. A forward-to-backward ratio of 20 was demonstrated for the electric dipole emission at 680 nm from a monolayer MoS2 by optically coupling it to a Si nanowire
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