Dyspraxia in a patient with corticobasal degeneration: the role of visual and tactile inputs to action

Objectives-To investigate the roles of visual and tactile information in a dyspraxic patient with corticobasal degeneration (CBD) who showed dramatic facilitation in miming the use of a tool or object when he was given a tool to manipulate; and to study the nature of the praxic and neuropsychological deficits in CBD. Methods-The subject had clinically diagnosed CBD, and exhibited alien limb behaviour and striking ideomotor dyspraxia. General neuropsychological evaluation focused on constructional and visuospatial abilities, calculation, verbal fluency, episodic and semantic memory, plus spelling and writing because impairments in this domain were presenting complaints. Four experiments assessed the roles of visual and tactile information in the facilitation of motor performance by tools. Experiment I evaluated the patient's performance of six limb transitive actions under six conditions: (1) after he described the relevant tool from memory, (2) after he was shown a Line drawing of the tool, (3) after he was shown a real exemplar of the tool, (4) after he watched the experimenter perform the action, (5) while he was holding the tool, and (6) immediately after he had performed the action with the tool but with the tool removed from his grasp. Experiment 2 evaluated the use of the same six tools when the patient had tactile but no visual information (while he was blindfolded). Experiments 3 and 4 assessed performance of actions appropriate to the same six tools when the patient had either neutral or inappropriate tactile feedback-that is, while he was holding a non-tool object or a different tool. Results-Miming of tool use was not facilitated by visual input; moreover, lack of visual information in the blindfolded condition did not reduce performance. The principal positive finding was a dramatic facilitation of the patient's ability to demonstrate object use when he was holding either the appropriate tool or a neutral object. Tools inappropriate to the requested action produced involuntary performance of the stimulus relevant action. Conclusions-Tactile stimulation was paramount in the facilitation of motor performance in tool use by this patient with CBD. This outcome suggests that tactile information should be included in models which hypothesise modality specific inputs to the action production system. Significant impairments in spelling and letter production that have not previously been reported in CBD have also been documented

Determination of the strange nucleon form factors

The strange contribution to the electric and magnetic form factors of the nucleon is determined at a range of discrete values of $Q^2$ up to $1.4$ GeV$^2$. This is done by combining recent lattice QCD results for the electromagnetic form factors of the octet baryons with experimental determinations of those quantities. The most precise result is a small negative value for the strange magnetic moment: $G_M^s(Q^2=0) = -0.07\pm0.03\,\mu_N$. At larger values of $Q^2$ both the electric and magnetic form factors are consistent with zero to within $2$-sigma

Charge Symmetry Violation in the Electromagnetic Form Factors of the Proton

Experimental tests of QCD through its predictions for the strange-quark content of the proton have been drastically restricted by our lack of knowledge of the violation of charge symmetry (CSV). We find unexpectedly tiny CSV in the proton's electromagnetic form factors by performing the first extraction of these quantities based on an analysis of lattice QCD data. The resulting values are an order of magnitude smaller than current bounds on proton strangeness from parity violating electron-proton scattering experiments. This result paves the way for a new generation of experimental measurements of the proton's strange form factors to challenge the predictions of QCD

On the unification of dwarf and giant elliptical galaxies

The near orthogonal distributions of dwarf elliptical (dE) and giant elliptical (E) galaxies in the mu_e-Mag and mu_e-log(R_e) diagrams have been interpreted as evidence for two distinct galaxy formation processes. However, continuous, linear relationships across the alleged dE/E boundary at M_B = -18 mag - such as those between central surface brightness (mu_0) and (i) galaxy magnitude and (ii) light-profile shape (n) - suggest a similar, governing formation mechanism. Here we explain how these latter two linear trends necessitate a different behavior for dE and E galaxies, exactly as observed, in diagrams involving mu_e (and also _e). A natural consequence is that the distribution of dEs and Es in Fundamental Plane type analyses that use the associated intensity I_e, or _e, are expected to appear different. Together with other linear trends across the alleged dE/E boundary, such as those between luminosity and color, metallicity, and velocity dispersion, it appears that the dEs form a continuous extension to the E galaxies. The presence of partially depleted cores in luminous (M_B < -20.5 mag) Es does however signify the action of a different physical process at the centers (< ~300 pc) of these galaxies.Comment: 5 pages from the proceedings of the 2004 conference "Penetrating bars through masks of cosmic dust: the Hubble tuning fork strikes a new note". Edited by D. L. Block, I. Puerari, K. C. Freeman, R. Groess, and E. K. Bloc

Knowing no fear

People with brain injuries involving the amygdala are often poor at recognizing facial expressions of fear, but the extent to which this impairment compromises other signals of the emotion of fear has not been clearly established. We investigated N.M., a person with bilateral amygdala damage and a left thalamic lesion, who was impaired at recognizing fear from facial expressions. N.M. showed an equivalent deficit affecting fear recognition from body postures and emotional sounds. His deficit of fear recognition was not linked to evidence of any problem in recognizing anger (a common feature in other reports), but for his everyday experience of emotion N.M. reported reduced anger and fear compared with neurologically normal controls. These findings show a specific deficit compromising the recognition of the emotion of fear from a wide range of social signals, and suggest a possible relationship of this type of impairment with alterations of emotional experience

Safety and efficacy of fluticasone propionate in the topical treatment of skin diseases

Fluticasone propionate - the first carbothioate corticosteroid - has been classified as a potent anti-inflammatory drug for dermatological use. It is available as 0.05% cream and 0.005% ointment formulations for the acute and maintenance treatment of patients with dermatological disorders such as atopic dermatitis, psoriasis and vitiligo. This glucocorticoid is characterized by high lipophilicity, high glucocorticoid receptor binding and activation, and a rapid metabolic turnover in skin. Although skin blanching following fluticasone propionate exceeds that of corticosteroids of medium strength, several clinical trials demonstrate a low potential for cutaneous and systemic side-effects, even in difficult-to-treat areas like the face, the eyelids and intertriginous areas. Even among paediatric patients with atopic dermatitis, fluticasone propionate proved to be safe and effective. These pharmacological and clinical properties are reflected by the high therapeutic index of this glucocorticoid

The physiological bases of hidden noise-induced hearing loss: protocol for a functional neuroimaging study

Background: Rodent studies indicate that noise exposure can cause permanent damage to synapses between inner hair cells and high-threshold auditory nerve fibers, without permanently altering threshold sensitivity. These demonstrations of what is commonly known as “hidden hearing loss” have been confirmed in several rodent species, but the implications for human hearing are unclear. Objective: Our Medical Research Council (MRC) funded programme aims to address this unanswered question, by investigating functional consequences of the damage to the human peripheral and central auditory nervous system that results from cumulative lifetime noise exposure. Behavioral and neuroimaging techniques are being used in a series of parallel studies aimed at detecting hidden hearing loss in humans. The planned neuroimaging study aims to (1) identify central auditory biomarkers associated with hidden hearing loss, (2) investigate if there are any additive contributions from tinnitus or diminished sound tolerance, which are often comorbid with hearing problems, and (3) explore the relation between subcortical functional Magnetic Resonance Imaging (fMRI) measures and the auditory brainstem response (ABR). Methods: Individuals aged 25 to 40 years with pure tone hearing thresholds ≤ 20 dB HL over the range 500 Hz to 8 kHz and no contraindications for MRI or signs of ear disease will be recruited into the study. Lifetime noise exposure will be estimated using an in-depth structured interview. Auditory responses throughout the central auditory system will be recorded using ABR and fMRI. Analyses will focus predominantly on correlations between lifetime noise exposure and auditory response characteristics. Results: This article reports the study protocol. The programme grant was awarded in July 2013. Enrollment for the study described in this protocol commenced in February 2017 and was completed in December 2017. Results are expected in 2018. Conclusions: This challenging and comprehensive study will have the potential to impact diagnostic procedures for hidden hearing loss, enabling early identification of noise-induced auditory damage via the detection of changes in central auditory processing. Consequently, this will generate the opportunity to give personalized advice regarding provision of ear defense and monitoring of further damage, thus reducing the incidence of noise-induced hearing loss

Occupational asthma: a review.

Occupational asthma is the most common form of occupational lung disease in the developed world at the present time. In this review, the epidemiology, pathogenesis/mechanisms, clinical presentations, management, and prevention of occupational asthma are discussed. The population attributable risk of asthma due to occupational exposures is considerable. Current understanding of the mechanisms by which many agents cause occupational asthma is limited, especially for low-molecular-weight sensitizers and irritants. The diagnosis of occupational asthma is generally established on the basis of a suggestive history of a temporal association between exposure and the onset of symptoms and objective evidence that these symptoms are related to airflow limitation. Early diagnosis, elimination of exposure to the responsible agent, and early use of inhaled steroids may play important roles in the prevention of long-term persistence of asthma. Persistent occupational asthma is often associated with substantial disability and consequent impacts on income and quality of life. Prevention of new cases is the best approach to reducing the burden of asthma attributable to occupational exposures. Future research needs are identified

Casting Light on Dark Matter

The prospects for detecting a candidate supersymmetric dark matter particle at the LHC are reviewed, and compared with the prospects for direct and indirect searches for astrophysical dark matter. The discussion is based on a frequentist analysis of the preferred regions of the Minimal supersymmetric extension of the Standard Model with universal soft supersymmetry breaking (the CMSSM). LHC searches may have good chances to observe supersymmetry in the near future - and so may direct searches for astrophysical dark matter particles, whereas indirect searches may require greater sensitivity, at least within the CMSSM.Comment: 16 pages, 13 figures, contribution to the proceedings of the LEAP 2011 Conferenc