Molecular Diagnostic Tests for Microsporidia

The Microsporidia are a ubiquitous group of eukaryotic obligate intracellular parasites which were recognized over 100 years ago with the description of Nosema bombycis, a parasite of silkworms. It is now appreciated that these organisms are related to the Fungi. Microsporidia infect all major animal groups most often as gastrointestinal pathogens; however they have been reported from every tissue and organ, and their spores are common in environmental sources such as ditch water. Several different genera of these organisms infect humans, but the majority of infections are due to either Enterocytozoon bieneusi or Encephalitozoon species. These pathogens can be difficult to diagnose, but significant progress has been made in the last decade in the development of molecular diagnostic reagents for these organisms. This report reviews the molecular diagnostic tests that have been described for the identification of the microsporidia that infect humans

Primary Closure and Iliac Osteotomy in the Treatment of Exstrophy of the Bladder: A Case Report

Exstrophy of the bladder is a rare but serious congenital affliction. Untreated, exstrophy is associated with unacceptable morbidity and mortality. A case report is presented in which primary closure of the bladder and bilateral iliac osteotomy was successfully employed to gain anatomic correction of the bladder defect. However, the value of this surgical technique in restoring normal function of the lower urinary tract system is questionable

Chagas' disease and AIDS

Chagas' disease caused by Trypanosoma cruzi is an opportunistic infection in the setting of HIV/AIDS. Some individuals with HIV and chronic T. cruzi infection may experience a reactivation, which is most commonly manifested by meningoencephalitis. A reactivation myocarditis is the second most common manifestation. These presentations may be difficult to distinguish from toxoplasmosis in individuals with HIV/AIDS. The overlap of HIV and Trypanosoma cruzi infection occurs not only in endemic areas but also in non-endemic areas of North America and Europe where the diagnosis may be even more difficult. The pathological features, diagnosis and the role of cytokines in the pathogenesis of the disease are discussed

Clinical review: Prognostic value of magnetic resonance imaging in acute brain injury and coma

Progress in management of critically ill neurological patients has led to improved survival rates. However, severe residual neurological impairment, such as persistent coma, occurs in some survivors. This raises concerns about whether it is ethically appropriate to apply aggressive care routinely, which is also associated with burdensome long-term management costs. Adapting the management approach based on long-term neurological prognosis represents a major challenge to intensive care. Magnetic resonance imaging (MRI) can show brain lesions that are not visible by computed tomography, including early cytotoxic oedema after ischaemic stroke, diffuse axonal injury after traumatic brain injury and cortical laminar necrosis after cardiac arrest. Thus, MRI increases the accuracy of neurological diagnosis in critically ill patients. In addition, there is some evidence that MRI may have potential in terms of predicting outcome. Following a brief description of the sequences used, this review focuses on the prognostic value of MRI in patients with traumatic brain injury, anoxic/hypoxic encephalopathy and stroke. Finally, the roles played by the main anatomical structures involved in arousal and awareness are discussed and avenues for future research suggested

Influence of vision on short-term sound localization training with non-individualized HRTF

International audiencePrevious studies have demonstrated that it is possible for humans to adapt to new HRTF, non-individualized or altered, in a short time period. While natural adaptation, through sound exposure, takes several weeks [1], some training programs have been employed to accelerate adaptation and improve performance on sound localization in a few days (see [2] for a review). The majority of these training programs are based on audio-visual positional or response feedback learning [3] (participants correct their answer after seeing the target position), or on active learning, for example through audio-proprioceptive manipulations [4] (blindfolded participants actively explore the sphere around them by playing a mini sonified version of hot-and-cold game). While all training programs are based on a bimodal coupling (audio-vision [3] or audio-proprioception [4]), they are rarely based on a trimodal one. Therefore, if vision is not necessary for adaptation [4], and audio-visual training can even be less efficient than other methods [1,2], the role of vision in short-term audio localization training remains unclear, especially when action and proprioception are already involved. Our study compares two versions of active trainings: an audio-proprioceptive one and an audio-visuo-proprioceptive one. We hypothesize that combining all modalities leads to better adaptation inducing better performances and a longer remaining effect.The experiment is developed in virtual reality using a HTC Vive as a head- and hand-tracker. 3D audio spatialization is obtained through Steam Audio’s non-individualized built-in HRTF. When applicable, 3D visual information is displayed directly on the Vive screen. A total of 36 participants, equally distributed in 3 groups (G1 to G3), participate in this between-subject design study.G1 is a control group receiving no training session, while the 2 other groups receive a training session of 12 minutes during 3 consecutive days. All the participants also had to perform 5 sound localization tests (no feedback, hand-pointing techniques, 2 repetitions × 33 positions, frontal space): one before the experiment, one after each training session, and the last one 1 week after the first day in order to evaluate the remaining effect. G2 receives an audio-proprioceptive training as exposed in [4]. Participants have to freely scan the space around them with their hand-held Vive controller to find an animal sound hidden around them. The controller-to-target angular distance is sonified and spatialized at the controller position. No visual information is provided. G3 receives the same task as in G2 but, a visual representation of a sphere is also displayed at the hand position during all training sessions (audio-visuo-proprioceptive situation). We measure the angular error in azimuth and elevation during localization tests. Performances are also analyzed in interaural polar coordinate system to discuss front/back and up/down confusion errors. Data from training sessions are logged (total number of found animals and detailed sequence of hand positions) to evaluate how training and vision influence scanning strategy. The experimental phase is taking place right now (10 participants have completed it for the moment) and extends until the end of April. Complete results will be available for the final version of the paper in June. References [1] Carlile, S., and Blackman, T. Relearning auditory spectral cues for locations inside and outside the visual field. J. Assoc. Res. Otolaryngol. 15, 249–263 (2014)[2] Strelnikov, K., Rosito, M., and Barrone, P. Effect of audiovisual training on monaural spatial hearing in horizontal plane. PLoS ONE 6:e18344 (2011)[3] Mendonça, C. A review on auditory space adaptation to altered head-related cues. Front. Neurosci. 8, 219 (2014)[4] Parseihian, G. & Katz, B.F.G. Rapid head-related transfer function adaptation using a virtual auditory environment. J. Acous. Soc. of America 131, 2948–2957 (2012

Classical trajectories in quantum transport at the band center of bipartite lattices with or without vacancies

Here we report on several anomalies in quantum transport at the band center of a bipartite lattice with vacancies that are surely due to its chiral symmetry, namely: no weak localization effect shows up, and, when leads have a single channel the transmission is either one or zero. We propose that these are a consequence of both the chiral symmetry and the large number of states at the band center. The probability amplitude associated to the eigenstate that gives unit transmission ressembles a classical trajectory both with or without vacancies. The large number of states allows to build up trajectories that elude the blocking vacancies explaining the absence of weak localization.Comment: 5 pages, 5 figure

Relativistic non-instantaneous action-at-a-distance interactions

Relativistic action-at-a-distance theories with interactions that propagate at the speed of light in vacuum are investigated. We consider the most general action depending on the velocities and relative positions of the particles. The Poincare invariant parameters that label successive events along the world lines can be identified with the proper times of the particles provided that certain conditions are impossed on the interaction terms in the action. Further conditions on the interaction terms arise from the requirement that mass be a scalar. A generic class of theories with interactions that satisfy these conditions is found. The relativistic equations of motion for these theories are presented. We obtain exact circular orbits solutions of the relativistic one-body problem. The exact relativistic one-body Hamiltonian is also derived. The theory has three components: a linearly rising potential, a Coulomb-like interaction and a dynamical component to the Poincar\'e invariant mass. At the quantum level we obtain the generalized Klein-Gordon-Fock equation and the Dirac equation

An extra-heating mechanism in Doppler-cooling experiments

In this paper we experimentally and theoretically investigate laser cooling of Strontium 88 atoms in one dimensional optical molasses. In our case, since the optical cooling dipole transition involves a $J_g=0$ groundstate, no Sisyphus-type mechanisms can occur. We are thus able to test quantitatively the predictions of the Doppler-cooling theory. We have found, in agreement with other similar experiments, that the measured temperatures are systematically larger than the theoretical predictions. We quantitatively interpret this discrepancy by taking into consideration the extra-heating mechanism induced by transverse spatial intensity fluctuations of the optical molasses. Experimental data are in good agreement with Monte-Carlo simulations of our theoretical model. We thus confirm the important role played by intensity fluctuations in the dynamics of cooling and for the steady-state regime