A personalized multi-channel FES controller based on muscle synergies to support gait rehabilitation after stroke

It has been largely suggested in neuroscience literature that to generate a vast variety of movements, the Central Nervous System (CNS) recruits a reduced set of coordinated patterns of muscle activities, defined as muscle synergies. Recent neurophysiological studies have recommended the analysis of muscle synergies to finely assess the patient's impairment, to design personalized interventions based on the specific nature of the impairment, and to evaluate the treatment outcomes. In this scope, the aim of this study was to design a personalized multi-channel functional electrical stimulation (FES) controller for gait training, integrating three novel aspects: (1) the FES strategy was based on healthy muscle synergies in order to mimic the neural solutions adopted by the CNS to generate locomotion; (2) the FES strategy was personalized according to an initial locomotion assessment of the patient and was designed to specifically activate the impaired biomechanical functions; (3) the FES strategy was mapped accurately on the altered gait kinematics providing a maximal synchronization between patient's volitional gait and stimulation patterns. The novel intervention was tested on two chronic stroke patients. They underwent a 4-week intervention consisting of 30-min sessions of FES-supported treadmill walking three times per week. The two patients were characterized by a mild gait disability (walking speed > 0.8 m/s) at baseline. However, before treatment both patients presented only three independent muscle synergies during locomotion, resembling two different gait abnormalities. After treatment, the number of extracted synergies became four and they increased their resemblance with the physiological muscle synergies, which indicated a general improvement in muscle coordination. The originally merged synergies seemed to regain their distinct role in locomotion control. The treatment benefits were more evident for one patient, who achieved a clinically important change in dynamic balance (Mini-Best Test increased from 17 to 22) coupled with a very positive perceived treatment effect (GRC = 4). The treatment had started the neuro-motor relearning process also on the second subject, but twelve sessions were not enough to achieve clinically relevant improvements. This attempt to apply the novel theories of neuroscience research in stroke rehabilitation has provided promising results, and deserves to be further investigated in a larger clinical study

Integrated Detector Control and Calibration Processing at the European XFEL

The European X-ray Free Electron Laser is a high-intensity X-ray light source currently being constructed in the area of Hamburg, that will provide spatially coherent X-rays in the energy range between $0.25\,\mathrm{keV}$ and $25\,\mathrm{keV}$. The machine will deliver $10\,\mathrm{trains/s}$, consisting of up to $2700\,\mathrm{pulses}$, with a $4.5\,\mathrm{MHz}$ repetition rate. The LPD, DSSC and AGIPD detectors are being developed to provide high dynamic-range Mpixel imaging capabilities at the mentioned repetition rates. A consequence of these detector characteristics is that they generate raw data volumes of up to $15\,\mathrm{Gbyte/s}$. In addition the detector's on-sensor memory-cell and multi-/non-linear gain architectures pose unique challenges in data correction and calibration, requiring online access to operating conditions and control settings. We present how these challenges are addressed within XFEL's control and analysis framework Karabo, which integrates access to hardware conditions, acquisition settings (also using macros) and distributed computing. Implementation of control and calibration software is mainly in Python, using self-optimizing (py) CUDA code, numpy and iPython parallels to achieve near-real time performance for calibration application.Comment: Proceeding ICALEPS 201

Individualized Prediction of Drug Resistance in People with Post-Stroke Epilepsy: A Retrospective Study

Background: The study aimed to develop a model and build a nomogram to predict the probability of drug resistance in people with post-stroke epilepsy (PSE). Methods: Subjects with epilepsy secondary to ischemic stroke or spontaneous intracerebral hemorrhage were included. The study outcome was the occurrence of drug-resistant epilepsy defined according to International League Against Epilepsy criteria. Results: One hundred and sixty-four subjects with PSE were included and 32 (19.5%) were found to be drug-resistant. Five variables were identified as independent predictors of drug resistance and were included in the nomogram: age at stroke onset (odds ratio (OR): 0.941, 95% confidence interval (CI) 0.907–0.977), intracerebral hemorrhage (OR: 6.292, 95% CI 1.957–20.233), severe stroke (OR: 4.727, 95% CI 1.573–14.203), latency of PSE (>12 months, reference; 7–12 months, OR: 4.509, 95% CI 1.335–15.228; 0–6 months, OR: 99.099, 95% CI 14.873–660.272), and status epilepticus at epilepsy onset (OR: 14.127, 95% CI 2.540–78.564). The area under the receiver operating characteristic curve of the nomogram was 0.893 (95% CI: 0.832–0.956). Conclusions: Great variability exists in the risk of drug resistance in people with PSE. A nomogram based on a set of readily available clinical variables may represent a practical tool for an individualized prediction of drug-resistant PSE

Clinical phenotype and functional characterization of CASQ2 mutations associated with Catecholaminergic Polymorphic Ventricular Tachycardia

BACKGROUND: Four distinct mutations in the human cardiac calsequestrin gene (CASQ2) have been linked to catecholaminergic polymorphic ventricular tachycardia (CPVT). The mechanisms leading to the clinical phenotype are still poorly understood because only 1 CASQ2 mutation has been characterized in vitro. METHODS AND RESULTS: We identified a homozygous 16-bp deletion at position 339 to 354 leading to a frame shift and a stop codon after 5aa (CASQ2(G112+5X)) in a child with stress-induced ventricular tachycardia and cardiac arrest. The same deletion was also identified in association with a novel point mutation (CASQ2(L167H)) in a highly symptomatic CPVT child who is the first CPVT patient carrier of compound heterozygous CASQ2 mutations. We characterized in vitro the properties of CASQ2 mutants: CASQ2(G112+5X) did not bind Ca2+, whereas CASQ2(L167H) had normal calcium-binding properties. When expressed in rat myocytes, both mutants decreased the sarcoplasmic reticulum Ca2+-storing capacity and reduced the amplitude of I(Ca)-induced Ca2+ transients and of spontaneous Ca2+ sparks in permeabilized myocytes. Exposure of myocytes to isoproterenol caused the development of delayed afterdepolarizations in CASQ2(G112+5X). CONCLUSIONS: CASQ2(L167H) and CASQ2(G112+5X) alter CASQ2 function in cardiac myocytes, which leads to reduction of active sarcoplasmic reticulum Ca2+ release and calcium content. In addition, CASQ2(G112+5X) displays altered calcium-binding properties and leads to delayed afterdepolarizations. We conclude that the 2 CASQ2 mutations identified in CPVT create distinct abnormalities that lead to abnormal intracellular calcium regulation, thus facilitating the development of tachyarrhythmias

Evolución de la resistencia a fluorquinolonas de Escherichia coli en muestras de orina de la comunidad en laboratorios de vigilancia de la resistencia a los antimicrobianos de la provincia de Buenos Aires (2005 a 2008)

Escherichia coli es el microorganismo más frecuente recuperado en las infecciones urinarias de origen comunitario y su tratamiento se instala en forma empírica con Norfloxacina, por lo cual es importante la vigilancia de la resistencia y la difusión de esos datos. La OPS/OMS ha desarrollado un programa de vigilancia, del cual participan 8 laboratorios de la Provincia de Buenos Aires. Para explorar la magnitud del problema se analizaron 10.350 cepas de pacientes ambulatorios entre los años 2005 y 2008. La resistencia encontrada en este estudio fue del 13% en los dos primeros años, 15% en el 2007 y del 14% en el 2008. Se clasificaron, además la resistencia por sexo y edad y se las comparó con la hallada en los años 2003 (6%) y 2004 (8%), con los demás centros argentinos de la red de Vigilancia y algunos países de Latinoamérica y España. Se concluyó que el uso de las FQ ha favorecido la diseminación de resistencia, y debe racionalizarse su administración en infecciones no complicadas. Para poder utilizarla en infecciones graves, en particular las intrahospitalarias.Facultad de Ciencias Veterinaria

Evolución de la resistencia a fluorquinolonas de Escherichia coli en muestras de orina de la comunidad en laboratorios de vigilancia de la resistencia a los antimicrobianos de la provincia de Buenos Aires (2005 a 2008)

Escherichia coli es el microorganismo más frecuente recuperado en las infecciones urinarias de origen comunitario y su tratamiento se instala en forma empírica con Norfloxacina, por lo cual es importante la vigilancia de la resistencia y la difusión de esos datos. La OPS/OMS ha desarrollado un programa de vigilancia, del cual participan 8 laboratorios de la Provincia de Buenos Aires. Para explorar la magnitud del problema se analizaron 10.350 cepas de pacientes ambulatorios entre los años 2005 y 2008. La resistencia encontrada en este estudio fue del 13% en los dos primeros años, 15% en el 2007 y del 14% en el 2008. Se clasificaron, además la resistencia por sexo y edad y se las comparó con la hallada en los años 2003 (6%) y 2004 (8%), con los demás centros argentinos de la red de Vigilancia y algunos países de Latinoamérica y España. Se concluyó que el uso de las FQ ha favorecido la diseminación de resistencia, y debe racionalizarse su administración en infecciones no complicadas. Para poder utilizarla en infecciones graves, en particular las intrahospitalarias.Facultad de Ciencias Veterinaria

Evolución de la resistencia a fluorquinolonas de <i>Escherichia coli</i> en muestras de orina de la comunidad en laboratorios de vigilancia de la resistencia a los antimicrobianos de la provincia de Buenos Aires (2005 a 2008)

Escherichia coli es el microorganismo más frecuente recuperado en las infecciones urinarias de origen comunitario y su tratamiento se instala en forma empírica con Norfloxacina, por lo cual es importante la vigilancia de la resistencia y la difusión de esos datos. La OPS/OMS ha desarrollado un programa de vigilancia, del cual participan 8 laboratorios de la Provincia de Buenos Aires. Para explorar la magnitud del problema se analizaron 10.350 cepas de pacientes ambulatorios entre los años 2005 y 2008. La resistencia encontrada en este estudio fue del 13% en los dos primeros años, 15% en el 2007 y del 14% en el 2008. Se clasificaron, además la resistencia por sexo y edad y se las comparó con la hallada en los años 2003 (6%) y 2004 (8%), con los demás centros argentinos de la red de Vigilancia y algunos países de Latinoamérica y España. Se concluyó que el uso de las FQ ha favorecido la diseminación de resistencia, y debe racionalizarse su administración en infecciones no complicadas. Para poder utilizarla en infecciones graves, en particular las intrahospitalarias.Facultad de Ciencias Veterinaria