Interacción con pantalla táctil de smartphone en pacientes con temblor esencial y sujetos sanos / Interaction with touchscreen smartphones in patients with essential tremor and healthy individuals

Introducción: El uso de smartphones en investigación biomédica está creciendo rápidamente en diferentes entornos clínicos. Realizamos un estudio piloto para obtener información sobre el uso de smartphones en pacientes con temblor esencial (TE) y en sujetos sanos, con el objetivo de evaluar si la realización de diversas tareas con las pantallas táctiles difiere entre grupos y describir factores de esta interacción.MétodoSe administró un cuestionario sobre el uso de smartphones a 31 pacientes con TE y 40 sujetos control apareados por edad y sexo. Acto seguido, los participantes interactuaron con una aplicación Android en desarrollo y realizaron 4 test basados en diferentes modos de interacción típicos con pantallas táctiles, con 5 repeticiones de cada tarea.ResultadoLos tipos de uso de smartphones así como su interacción no fueron significativamente diferentes entre pacientes y controles. La edad y el número de usos del smartphone son factores clave en esta interacción con pantallas táctiles.ConclusiónEstas observaciones apoyan el uso de las pantallas táctiles de los smartphones para investigación en TE, pero se requieren más estudios. (AU)

Introduction: Smartphones use in biomedical research is becoming more prevalent in different clinical settings. We performed a pilot study to obtain information on smartphone use by patients with essential tremor (ET) and healthy controls, with a view to determining whether performance of touchscreen tasks is different between these groups and describing touchscreen interaction factors.MethodA total of 31 patients with ET and 40 sex- and age-matched healthy controls completed a descriptive questionnaire about the use of smartphones. Participants subsequently interacted with an under-development Android application, and performed 4 tests evaluating typical touchscreen interaction gestures; each test was performed 5 times.ResultThe type of smartphone use and touchscreen interaction were not significantly different between patients and controls. Age and frequency of smartphone use are key factors in touchscreen interaction.ConclusionOur results support the use of smartphone touchscreens for research into ET, although further studies are required. (AU)

Interaction with touchscreen smartphones in patients with essential tremor and healthy individuals.

INTRODUCTION: Smartphone use in biomedical research is becoming more prevalent in different clinical settings. We performed a pilot study to obtain information on smartphone use by patients with essential tremor (ET) and healthy controls, with a view to determining whether performance of touchscreen tasks is different between these groups and describing touchscreen interaction factors. METHOD: A total of 31 patients with ET and 40 sex- and age-matched healthy controls completed a descriptive questionnaire about the use of smartphones. Participants subsequently interacted with an under-development Android application, and performed 4 tests evaluating typical touchscreen interaction gestures; each test was performed 5 times. RESULT: The type of smartphone use and touchscreen interaction were not significantly different between patients and controls. Age and frequency of smartphone use are key factors in touchscreen interaction. CONCLUSION: Our results support the use of smartphone touchscreens for research into ET, although further studies are required.

Interaction with touchscreen smartphones in patients with essential tremor and healthy individuals. / Interacción con pantalla táctil de smartphone en pacientes con temblor esencial y sujetos sanos.

INTRODUCTION: Smartphones use in biomedical research is becoming more prevalent in different clinical settings. We performed a pilot study to obtain information on smartphone use by patients with essential tremor (ET) and healthy controls, with a view to determining whether performance of touchscreen tasks is different between these groups and describing touchscreen interaction factors. METHOD: A total of 31 patients with ET and 40 sex- and age-matched healthy controls completed a descriptive questionnaire about the use of smartphones. Participants subsequently interacted with an under-development Android application, and performed 4 tests evaluating typical touchscreen interaction gestures; each test was performed 5 times. RESULT: The type of smartphone use and touchscreen interaction were not significantly different between patients and controls. Age and frequency of smartphone use are key factors in touchscreen interaction. CONCLUSION: Our results support the use of smartphone touchscreens for research into ET, although further studies are required.

Locomotor training through a novel robotic platform for gait rehabilitation in pediatric population: short report.

BACKGROUND: Cerebral Palsy (CP) is a disorder of posture and movement due to a defect in the immature brain. The use of robotic devices as alternative treatment to improve the gait function in patients with CP has increased. Nevertheless, current gait trainers are focused on controlling complete joint trajectories, avoiding postural control and the adaptation of the therapy to a specific patient. This paper presents the applicability of a new robotic platform called CPWalker in children with spastic diplegia. FINDINGS: CPWalker consists of a smart walker with body weight and autonomous locomotion support and an exoskeleton for joint motion support. Likewise, CPWalker enables strategies to improve postural control during walking. The integrated robotic platform provides means for testing novel gait rehabilitation therapies in subjects with CP and similar motor disorders. Patient-tailored therapies were programmed in the device for its evaluation in three children with spastic diplegia for 5 weeks. After ten sessions of personalized training with CPWalker, the children improved the mean velocity (51.94 ± 41.97 %), cadence (29.19 ± 33.36 %) and step length (26.49 ± 19.58 %) in each leg. Post-3D gait assessments provided kinematic outcomes closer to normal values than Pre-3D assessments. CONCLUSIONS: The results show the potential of the novel robotic platform to serve as a rehabilitation tool. The autonomous locomotion and impedance control enhanced the children's participation during therapies. Moreover, participants' postural control was substantially improved, which indicates the usefulness of the approach based on promoting the patient's trunk control while the locomotion therapy is executed. Although results are promising, further studies with bigger sample size are required.

Predictive classification of self-paced upper-limb analytical movements with EEG.

The extent to which the electroencephalographic activity allows the characterization of movements with the upper limb is an open question. This paper describes the design and validation of a classifier of upper-limb analytical movements based on electroencephalographic activity extracted from intervals preceding self-initiated movement tasks. Features selected for the classification are subject specific and associated with the movement tasks. Further tests are performed to reject the hypothesis that other information different from the task-related cortical activity is being used by the classifiers. Six healthy subjects were measured performing self-initiated upper-limb analytical movements. A Bayesian classifier was used to classify among seven different kinds of movements. Features considered covered the alpha and beta bands. A genetic algorithm was used to optimally select a subset of features for the classification. An average accuracy of 62.9 ± 7.5% was reached, which was above the baseline level observed with the proposed methodology (30.2 ± 4.3%). The study shows how the electroencephalography carries information about the type of analytical movement performed with the upper limb and how it can be decoded before the movement begins. In neurorehabilitation environments, this information could be used for monitoring and assisting purposes.

Detection of the onset of upper-limb movements based on the combined analysis of changes in the sensorimotor rhythms and slow cortical potentials.

OBJECTIVE: Characterizing the intention to move by means of electroencephalographic activity can be used in rehabilitation protocols with patients' cortical activity taking an active role during the intervention. In such applications, the reliability of the intention estimation is critical both in terms of specificity 'number of misclassifications' and temporal accuracy. Here, a detector of the onset of voluntary upper-limb reaching movements based on the cortical rhythms and the slow cortical potentials is proposed. The improvement in detections due to the combination of these two cortical patterns is also studied. APPROACH: Upper-limb movements and cortical activity were recorded in healthy subjects and stroke patients performing self-paced reaching movements. A logistic regression combined the output of two classifiers: (i) a naïve Bayes classifier trained to detect the event-related desynchronization preceding the movement onset and (ii) a matched filter detecting the bereitschaftspotential. The proposed detector was compared with the detectors by using each one of these cortical patterns separately. In addition, differences between the patients and healthy subjects were analysed. MAIN RESULTS: On average, 74.5 ± 13.8% and 82.2 ± 10.4% of the movements were detected with 1.32 ± 0.87 and 1.50 ± 1.09 false detections generated per minute in the healthy subjects and the patients, respectively. A significantly better performance was achieved by the combined detector (as compared to the detectors of the two cortical patterns separately) in terms of true detections (p = 0.099) and false positives (p = 0.0083). SIGNIFICANCE: A rationale is provided for combining information from cortical rhythms and slow cortical potentials to detect the onsets of voluntary upper-limb movements. It is demonstrated that the two cortical processes supply complementary information that can be summed up to boost the performance of the detector. Successful results have been also obtained with stroke patients, which supports the use of the proposed system in brain-computer interface applications with this group of patients.

Upper-limb muscular electrical stimulation driven by EEG-based detections of the intentions to move: a proposed intervention for patients with stroke.

This study proposes an intervention for stroke patients in which electrical stimulation of muscles in the affected arm is supplied when movement intention is detected from the electroencephalographic signal. The detection relies on the combined analysis of two movement related cortical patterns: the event-related desynchronization and the bereitschaftspotential. Results with two healthy subjects and three chronic stroke patients show that reliable EEG-based estimations of the movement onsets can be generated (on average, 66.9 ± 26.4 % of the movements are detected with 0.42 ± 0.17 false activations per minute) which in turn give rise to electrical stimuli providing sensory feedback tightly associated to the movement planning (average detection latency of the onsets of the movements was 54.4 ± 287.9 ms).

A computational knowledge-based model for emulating human performance in the Iowa Gambling Task.

A new computational knowledge-based model for emulating human performance in decision making tasks is proposed. This model is mainly based on the knowledge acquired through past experience, the knowledge extracted from the environment and the relationships between the concepts that represent these two kinds of knowledge. The proposed model divides the decision making process into two phases. The first phase lies in the estimation of the decision outcomes using a net of concepts. In the second phase, the proposed model uses a value function to score each possible alternative. The design of the model focuses on some psychological and neurophysiological evidence from current research. In order to validate the model, it is compared with other widely used models that implement different theories of decision making under risk and uncertainty. The model comparison is centered on a well defined task, the Iowa Gambling Task, used in several psychological experiments. The comparison applies an evaluation method based on the optimization of each model in order to emulate human performance individually starting both the participant and the model from the same environmentally available information. The results show that the performance of the proposed model is quantitatively better than the other compared models. Besides, using relevant concepts extracted from interviews with the participants increases the performance of the proposed model.

In vitro efficiency of combined acid-heat treatments for protecting sunflower meal proteins against ruminal degradation.

Efficacy of combined acid-heat treatments to protect crude protein (CP) against ruminal degradation has not been extensively researched. Four in vitro trials (Daisy technology) with orthophosphoric and malic acids were performed to examine effects on protection of sunflower meal protein. In Trial 1, effects of the solution volume for adding two doses of orthophosphoric acid (0.4 and 1.2 eq/kg sunflower meal) were tested using five dilution volumes (80, 160, 240, 320 and 400 ml/kg of feed) for each acid dose. Samples were heated at 60°C. The quantity of CP that remained undegraded after 20 h in vitro (IVUCP) increased with the amount of acid added (P = 0.01). Increasing the dilution volume also tended (P = 0.065) to increase IVUCP. Therefore, a dilution volume of 400 ml/kg was employed in all further trials. In Trial 2, treatments with solutions of orthophosphoric and malic acids (1.2, 2.4, 3.6 and 4.8 eq/kg) and 60°C of drying temperature were used. Increased CP protection with increased acid doses was described. In this and further trials, higher protective effects of malic acid than orthophosphoric acid were also shown. In Trial 3, the effects of both these acids, four acid concentrations (0.6, 1.2, 1.8 and 2.4 eq/kg) and three levels of heat treatment required for drying the samples (100, 150 and 200°C for 60, 30 and 20 min, respectively) were evaluated. An interaction acid type × concentration × temperature was shown. In addition, interactions concentration × temperature was shown in each acid. With heat treatments of 100°C to 150°C, benefits were not obtained after increasing the acid dose over 0.8 eq/kg. The increase of the heat treatments to 200°C and the acid dose up to 1.2 eq/kg increased protection, but to exceed this dose did not improve protection. In Trial 4, available lysine, CP solubility in McDougall buffer and IVUCP were compared after treatment with water or solutions (0.8 eq/kg) of orthophosphoric or malic acids using 100°C and 150°C heat treatments as described in Trial 3. No effects on available lysine were observed. Both CP solubility and IVUCP were reduced to a greater degree by acids than by water treatment. The results showed a high effectiveness of acid-heat treatments. Levels of protection are dependent on the acid dose, its dilution, acid type and drying conditions.

An asynchronous BMI system for online single-trial detection of movement intention.

This paper presents an approach for an asynchronous BMI proposed as a switching part of a tremor suppression system developed for real-time continuous conditions. The main purpose of this BMI-switch is to anticipate the execution of self-initiated movements performed after relatively long periods of inactivity. The performance indicators used for the detector validation are specially suited for the continuous characteristic of the paradigm used and it is demonstrated that our ERD-based bayesian classifier solution is a reliable option, detecting a high rate of positive cases and generating very few false positives during long intervals of inactivity. The subjects analyzed for our detector validation were patients with neurological tremor caused by different pathologies in order to assure the adaptability of our system.

Estrategia para la mejora del uso de antibióticos en pediatría / Strategy for improving the use of antibiotics in paediatrics

Dentro de las actividades del farmacéutico de atención primaria se encuentra el análisis del perfil de prescripción farmacológica, la identificación de áreas de mejora y la puesta en marcha de estrategias para mejorar el uso de los medicamentos dentro del Distrito. En octubre de 2008, la prescripción de antibióticos en el Distrito se caracterizaba por una alta variabilidad en la selección de antibióticos por parte de los pediatras, que daba como resultado un global del indicador de calidad del Contrato Programa del Servicio Andaluz de Salud peor que el de la media de Andalucía. Todo esto junto con la alta frecuentación de población pediátrica a los servicios de urgencias y la discrepancia entre criterios de prescripción en servicios de urgencias y pediatras del Equipo Básico de Atención Primaria (EBAP), motivó el desarrollo del presente trabajo. Nuestro objetivo fue mejorar el perfil de utilización de antibióticos en pediatría en Atención Primaria. Para ello se diseño un plan de mejora consistente en a)la formación de un grupo de mejora constituido por pediatras, farmacéuticos y coordinador de urgencias, b) elaboración de una “Guía empírica sobre antibioterapia pediátrica en AP”, adaptada y consensuada en el ámbito del Distrito, c) difusión de la guía a todos los pediatras, médicos de Dispositivo de Cuidados Críticos y Urgencias (DCCU) y Dirección Médica del Hospital de referencia, d) sesiones formativas a los médicos de DCCU impartidas por un pediatra del grupo, e) para la evaluación del plan se midieron indicadores de calidad en la prescripción pediátrica durante los meses enero-abril 2009 respecto al año anterior y se elaboró una encuesta dirigida a los pediatras de EBAP de valoración del plan(AU)

La selección de un antibiótico debe basarse en criterios de eficacia, seguridad, adecuación y coste. En este sentido, la intervención produjo una mejora en la selección de antibióticos en pediatría a nivel de Atención Primaria, disminuyendo la variabilidad de la prescripción. En concreto, se incrementó la descripción de antibióticos de primera elección, bajo criterios de práctica clínica (amoxicilina, ampicilina, penicilinas frente a Gram positivo y cloxacilina) frente a macrólidos y cefalosporinas de 2ª y 3ª generación. Este aumento debe traducirse en un aumento de la eficiencia terapéutica y disminución de la aparición de resistencias bacterianas y efectos adversos. La aceptación del plan de mejora entre los profesionales fue bueno debido, entre otras causas, a la participación activa de los mismos(AU)

Among the activities of Primary Care Pharmacist we have drug prescription profiles analysis. In October 2008, antibiotics prescription at Distrito Costa del Sol was characterized by a high variability in the selection of antibiotics by paediatricians, which resulted in an overall quality indicator worse than the regional mean value. All this together with the high frequency of paediatric emergency services and discrepancy in prescription criteria with Primary Care Services prompted the development of this work. We designed an improvement plan consisting on establishing a multidisciplinary group that generateda “Guide on empirical antibiotic therapy”. This guide was distributed to all paediatricians and Emergency Services along with training sessions. Quality indicators in paediatric prescription were measured from January to April 2009 and compared to same period 2008 along with a satisfaction survey. We observed an increased prescription of antibiotics of choice that may lead to an improved therapeutic efficiency and decreased bacterial resistances and adverse effects. Acceptance of the plan by professionals was high based on, among other reasons, their active participation(AU)

Formation of Amadori compounds in dehydrated fruits.

The presence of Amadori compounds in commercial dehydrated fruits has been shown through HPLC analysis of the corresponding 2-furoylmethyl-amino acids obtained by acid hydrolysis. Furosine (2-furoylmethyl-lysine) was the main 2-furoylmethyl derivative observed in dried figs and apricot samples, whereas in prunes and dates similar amounts of furosine and 2-furoylmethyl-gamma-aminobutyric acid were detected. A considerable variation of 2-furoylmethyl-amino acid contents among commercial raisin samples was observed. 2-Furoylmethyl-gamma-aminobutyric acid and 2-furoylmethyl-arginine, the most abundant 2-furoylmethyl-amino acids, ranged between 9.9 and 75.8 mg/100 g sample and 10.0 and 62.5 mg/100 g sample, respectively. Most of the Amadori compounds present in raisins seem to have originated during the commercial shelf life period rather than during processing. Determination of 2-furoylmethyl-amino acids could be used as a method of controlling commercial dehydrated fruit and selecting storage conditions.

Use of 2-furoylmethyl derivatives of GABA and arginine as indicators of the initial steps of maillard reaction in orange juice.

The formation of 2-furoylmethyl derivatives of GABA (2-FM-GABA) and arginine (2-FM-Arg) as early indicators of nonenzymatic browning in different types of orange juice was studied. In dehydrated orange juice, the presence of 2-FM-GABA and 2-FM-Arg was detected from the first day of storage at 30 degrees C. In this type of juice, the content of these two compounds increased with temperature (30, 50 degrees C) and time (1-7 days) of storage. A noticeable increase in 5-hydroxymethylfurfural was only observed after 4 days of storage at 50 degrees C. No formation of 2-FM-GABA and 2-FM-Arg was detected in liquid orange juice heated under conditions similar to those used in the industry. These furoylmethyl derivatives were also found in commercial orange juice made from concentrates. A slight increase in their concentration was observed in the two samples stored during 8 months at room temperature. According to the results obtained, 2-FM-GABA and 2-FM-Arg contents could be suitable indicators to assess the main modifications due to Maillard reaction produced during the manufacture and/or storage of orange juice concentrates.

Presence of 2-furoylmethyl derivatives in hydrolysates of processed tomato products.

Acid hydrolysis of Amadori compounds yields the corresponding 2-furoylmethylamino acids (2-FM-AA) that can be analyzed by ion-pair HPLC. The relative proportions of the different 2-FM-AA present in the hydrolysates of tomato products were determined to assess their usefulness as indicators of quality. In the lyophilized tomato samples stored at 50 degrees C and a(w) = 0.44 the formation of 2-FM derivatives of alanine, gamma-aminobutyric acid (GABA), asparagine, aspartic acid, glutamic acid, lysine, serine, and threonine was detected. In commercial tomato products the most abundant 2-FM-AA was 2-FM-GABA (from traces to 26.4 mg/100 g of dry matter) followed by 2-FM-lysine (furosine). Differences in 2-FM-AA contents among samples may be related to processing and storage conditions.

Synthesis and characterization of gamma-N-(2-furoylmethyl)aminobutyric acid.

The product of acid hydrolysis of the Amadori compound gamma-N-(1-deoxy-D-fructosyl)aminobutyric acid was isolated and identified by (1)H NMR and (13)C NMR as gamma-N-(2-furoylmethyl)aminobutyric acid. This compound is an analogue to furosine, formed during acid hydrolysis of the corresponding Amadori compound. The retention time of the isolated compound was the same as that of the main peak observed in acid hydrolysates of stored orange juice powder. gamma-N-(2-Furoylmethyl)aminobutyric acid can be a useful indicator of the early stages of Maillard reaction in foods containing free gamma-aminobutyric acid.

Early stages of maillard reaction in dehydrated orange juice.

The formation of furoylmethyl derivatives of amino acids as indicators of the early stages of Maillard reaction in dehydrated orange juices and model systems was studied. In stored dehydrated orange juices, the presence of furoylmethyl derivatives of arginine, asparagine, proline, alanine, glutamic acid, and GABA was detected. Their formation increased with temperature of storage. After 2 weeks at 30 degrees C and a(w) = 0.44, the reconstituted orange juice contained 94 mg/L furoylmethyl derivatives, whereas up to 1215 mg/L was detected in samples stored at 50 degrees C.

Evaluation of total antioxidant potential (TRAP) and total antioxidant reactivity from luminol-enhanced chemiluminescence measurements.

The effect of antioxidants and biological fluids on the intensity of luminol induced chemiluminescence by radicals derived from the thermolysis of 2,2'-azo-bis(2-amidinopropane) has been employed to monitor TRAP and TOTAL ANTIOXIDANT REACTIVITY (TAR) levels. The latter parameter, which considers not only the quantity of oxidants but also their reactivity, is considered a potentially more useful index of the antioxidant status of a biological fluid. The results obtained employing human blood plasma and human urine show that the detected antioxidant capacity of both fluids is mainly related to the uric acid concentration of the samples.

On the use of the quenching of luminol luminescence to evaluate SOD activity.

Addition of horseradish peroxidase to a luminol solution (pH = 9.4) produces a burst of light followed by a steady luminescence that lasts for several minutes. This steady-state luminescence is readily quenched by SOD, with a Q1/2 concentration (the additive concentration needed to decrease by one-half the emitted luminescence intensity) of c.a. 4 ng/ml (14 mU/ml). The luminescence intensity decrease can then be employed to evaluate SOD activity in SOD-containing samples. However, the light intensity can also be quenched by additives, such as Trolox, that are able to trap luminol-derived intermediates. It is proposed that double quenching experiments must be performed in order to be able to relate the observed effect of an additive to its SOD-like activity.

[Percutaneous valvuloplasty in congenital aortic valve stenosis]. / Valvuloplastia percutânea em estenose valvular aórtica congênita.

PURPOSE: To show the initial experience of Institute of Cardiology of Rio Grande do Sul in the treatment of congenital valvular aortic stenosis with percutaneous balloon aortic valvuloplasty. METHODS: Twenty four patients were submitted to the procedure, 14 males and 10 females. The mean age 7 years (4 days-17 years). Four patients were aged below 30 days and three patients had previous surgical valvuloplasty. The percutaneous balloon aortic valvuloplasty were made the retrograde approach in all patients. RESULTS: The peak systolic pressure gradient was reduced from 65.96 +/- 22.68 to 27.08 +/- 18.74 mmHg. The procedure resulted in aortic regurgitation in seven patients and worsened aortic regurgitation in two patients. One patient had cardiac arrest that was reverted by cardiopulmonary resuscitation, this patient had hospital discharge without sequel. Five patients had acute femoral artery thrombosis, and hemorrhage in the site of puncture happened in one patient. CONCLUSION: The percutaneous balloon aortic valvuloplasty results in effective reduction of the peak systolic pressure gradient, it is a save and effective therapy in patients with congenital valvular aortic stenosis. Further evaluation of the long term results are necessary for definitive conclusions.

Luminol luminescence induced by 2,2'-Azo-bis(2-amidinopropane) thermolysis.

2,2'-Azo-bis(2-amidinopropane) thermolysis induces luminol luminescence. The luminescence intensity is quenched by SOD, catalase, Trolox and human blood serum. However, the time course of the light intensity profile is different for the different additives. In particular, the quenching efficiency of Trolox and human blood serum decreases with time after addition. Double quenching experiments show that SOD and Trolox are not competitive quenchers, while a simple competition can be established between Trolox and human blood serum in trapping a common intermediate. From the kinetic analysis of the data it is concluded that, at least at low additive concentrations, Trolox scavenges a luminol derived radical. Higher concentrations of Trolox or human blood serum produce induction times that are proportional to the additives concentrations. The possibility of employing luminol luminescence in the evaluation of TRAP levels and the capacity of biological samples to scavenge free radicals is discussed.