Comparative Study of the Impact of Human Leukocyte Antigens on Renal Transplant Survival in Andalusia and the United States.

Renal transplantation is the treatment of choice for patients suffering from chronic renal disease, one of the leading causes of death worldwide. Among the biological barriers that may increase the risk of acute renal graft rejection is the presence of human leukocyte antigen (HLA) incompatibilities between donor and recipient. This work presents a comparative study of the influence of HLA incompatibilities on renal transplantation survival in the Andalusian (South of Spain) and United States (US) population. The main objective is to analyse the extent to which results about the influence of different factors on renal graft survival can be generalised to different populations. The Kaplan-Meier estimator and the Cox model have been used to identify and quantify the impact on the survival probability of HLA incompatibilities, both in isolation and in conjunction with other factors associated with the donor and recipient. According to the results obtained, HLA incompatibilities considered in isolation have negligible impact on renal survival in the Andalusian population and a moderate impact in the US population. Grouping by HLA score presents some similarities for both populations, while the sum of all HLA scores (aHLA) only has an impact on the US population. Finally, the graft survival probability of the two populations differs when aHLA is considered in conjunction with blood type. The results suggest that the disparities in the renal graft survival probability between the two populations under study are due not only to biological and transplantation-associated factors, but also to social-health factors and ethnic heterogeneity between populations.

A Sensor-Based mHealth Platform for Remote Monitoring and Intervention of Frailty Patients at Home.

Frailty syndrome is an independent risk factor for serious health episodes, disability, hospitalization, falls, loss of mobility, and cardiovascular disease. Its high reversibility demands personalized interventions among which exercise programs are highly efficient to contribute to its delay. Information technology-based solutions to support frailty have been recently approached, but most of them are focused on assessment and not on intervention. This paper describes a sensor-based mHealth platform integrated in a service-based architecture inside the FRAIL project towards the remote monitoring and intervention of pre-frail and frail patients at home. The aim of this platform is constituting an efficient and scalable system for reducing both the impact of aging and the advance of frailty syndrome. Among the results of this work are: (1) the development of elderly-focused sensors and platform; (2) a technical validation process of the sensor devices and the mHealth platform with young adults; and (3) an assessment of usability and acceptability of the devices with a set of pre-frail and frail patients. After the promising results obtained, future steps of this work involve performing a clinical validation in order to quantify the impact of the platform on health outcomes of frail patients.

Effects of genetics and altitude on lung function.

OBJECTIVES: The aim of this work is to present a review on the impact of genetics and altitude on lung function from classic and recent studies. DATA SOURCE: A systematic search has been carried out in different databases of scientific studies, using keywords related to lung volumes, spirometry, altitude and genetics. RESULTS: The results of this work have been structured into three parts. First, the relationship between genes and lung function. Next, a review of the genetic predispositions related to respiratory adaptation of people who inhabit high-altitude regions for millennia. Finally, temporary effects and long-term acclimatisation on respiratory physiology at high altitude are presented. CONCLUSIONS: The works focused on the influence of genetics and altitude on lung function are currently of interest in terms of studying the interactions between genetic, epigenetic and environmental factors in the configuration of the pathophysiological adaptation patterns.

Dynamic Walking of a Legged Robot in Underwater Environments.

In this research, the dynamic walking of a legged robot in underwater environments is proposed. For this goal, the underwater zero moment point (Uzmp) is proposed in order to generate the trajectory of the centre of the mass of the robot. Also, the underwater zero moment point auxiliary (Uzmp aux.) is employed to stabilize the balance of the robot before it undergoes any external perturbations. The concept demonstration of a legged robot with hydraulic actuators is developed. Moreover, the control that was used is described and the hydrodynamic variables of the robot are determined. The results demonstrate the validity of the concepts that are proposed in this article, and the dynamic walking of the legged robot in an underwater environment is successfully demonstrated.

Potential Energy Distribution of Redundant Cable-Driven Robot Applied to Compliant Grippers: Method and Computational Analysis.

Cable-driven parallel robots with a redundant configuration have infinite solutions for their cable tension distribution to provide a specific wrench to the end-effector. Redundancy is commonly used to increase the workspace and stiffness or to achieve secondary objectives like energetic minimization or additional movements. This article presents a method based on energy distribution to handle the redundancy of cable-driven parallel robots. This method allows the deformation and tension of each link to be related to the total energy available in the parallel robot. The study of energy distribution expression allows deformation, tension, and position to be combined. It also defines the range of tension and deformation that cables can achieve without altering the wrench exerted on the end-effector. This range is used with a passive reconfigurable end-effector to control the position of two grippers attached to some cables which act as compliant actuators. The relationship between the actuators' energy and their corresponding gripper positions is also provided. In this way, energy measurement from the actuators allows the grasping state to be sensed. The results are validated using multibody dynamic software.

Experimental and Computational Methodology for the Determination of Hydrodynamic Coefficients Based on Free Decay Test: Application to Conception and Control of Underwater Robots.

Hydrodynamic coefficients are essential for the development of underwater robots; in particular, for their design and navigation control. To obtain these coefficients, several techniques exist. These methods are usually experimental, but, more recently, some have been designed by a combination of experiments with computational methods based on Computational Fluid Dynamics (CFD). One method for obtaining the hydrodynamic coefficients of an ROV (Remote Operated Vehicle) is by using an experimental PMM (Planar Motion Mechanism) or CWC (Circular Water Channel); however, the use of these experimental infrastructures is costly. Therefore, it is of interest to obtain these coefficients in other ways, for example, by the use of simple experiments. The Free Decay Test is an ideal type of experiment, as it has a low cost and is simple to implement. In this paper, two different free decay tests were carried out, to which three different methods for obtaining coefficients were applied. They were compared with results obtained by CFD simulation to conduct a statistical analysis in order to determine their behaviours. It was possible to obtain values of the drag and added mass coefficients for the models analysed, where the values were obtained for an Underwater Drone Robot (UDrobot).

A Sensor Based on a Spherical Parallel Mechanism for the Measurement of Fluid Velocity: Physical Modelling and Computational Analysis.

In this article, a new method was developed to measure the velocity of a fluid using a sensor, based on the use of a spherical parallel mechanism with three degrees-of-freedom (DOF). This sensor transforms the kinetic energy of the fluid into potential energy by deforming the parallel mechanism. This deformation is due to the impact of the fluid on a sphere attached to the platform of the parallel mechanism. Through the acquisition of data from a sensor using an inertial measurement unit (IMU) in the sphere, an algorithm calculates the velocity and direction of the fluid. In this article, a mathematical model of the mechanism and an algorithm for correctly measuring the velocity and direction of the fluid is developed; this algorithm is tested through a simulation in the Adams software, and the MATLAB software is used to execute the algorithm. The results show that the algorithm calculates the velocity and the direction of the fluid correctly, demonstrating the technical feasibility of the sensor.

Cable-Driven Parallel Robot with Reconfigurable End Effector Controlled with a Compliant Actuator.

Redundancy in cable-driven parallel robots provides additional degrees of freedom that can be used to achieve different objectives. In this robot, this degree of freedom is used to act on a reconfigurable end effector with one degree of freedom. A compliant actuator actuated by one motor exerts force on both bodies of the platform. Due to the high tension that appears in this cable in comparison with the rest of the cables, an elastic model was developed for solving the kinestostatic and wrench analysis. A linear sensor was used in one branch of this cable mechanism to provide the needed intermediate values. The position of one link of the platform was fixed in order to focus this analysis on the relationship between the cables and the platform's internal movement. Position values of the reconfigurable end effector were calculated and measured as well as the tension at different regions of the compliant actuator. The theoretical values were compared with dynamic simulations and real prototype results.

Smart Vest for Respiratory Rate Monitoring of COPD Patients Based on Non-Contact Capacitive Sensing.

In this paper, a first approach to the design of a portable device for non-contact monitoring of respiratory rate by capacitive sensing is presented. The sensing system is integrated into a smart vest for an untethered, low-cost and comfortable breathing monitoring of Chronic Obstructive Pulmonary Disease (COPD) patients during the rest period between respiratory rehabilitation exercises at home. To provide an extensible solution to the remote monitoring using this sensor and other devices, the design and preliminary development of an e-Health platform based on the Internet of Medical Things (IoMT) paradigm is also presented. In order to validate the proposed solution, two quasi-experimental studies have been developed, comparing the estimations with respect to the golden standard. In a first study with healthy subjects, the mean value of the respiratory rate error, the standard deviation of the error and the correlation coefficient were 0.01 breaths per minute (bpm), 0.97 bpm and 0.995 (p < 0.00001), respectively. In a second study with COPD patients, the values were −0.14 bpm, 0.28 bpm and 0.9988 (p < 0.0000001), respectively. The results for the rest period show the technical and functional feasibility of the prototype and serve as a preliminary validation of the device for respiratory rate monitoring of patients with COPD.

Factores que afectan a la función pulmonar: una revisión bibliográfica / Factors Affecting Lung Function: A Review of the Literature

Los valores de referencia de las pruebas de función pulmonar están basados históricamente en factores antropométricos como el peso, la altura, el género y la edad. La FVC y el FEV1 disminuyen con la edad y, en contraposición, volúmenes y capacidades como el RV y la FRC se incrementan. La TLC, CV, RV, FVC y FEV1 se ven afectados por la altura, puesto que son proporcionales al tamaño corporal. Esto significa que un individuo alto sufrirá un mayor decremento de sus volúmenes pulmonares a medida que aumente su edad. Algunas variables decrecen exponencialmente con el incremento del peso, como la FRC y el ERV, de tal forma que los sujetos con obesidad mórbida pueden llegar a alcanzar un volumen corriente cercano al RV. Los hombres poseen vías aéreas de conducción más largas que las mujeres, dando lugar a una mayor resistencia específica de las vías respiratorias. El mayor trabajo respiratorio en mujeres para aumentar la ventilación provoca que, en condiciones con la misma intensidad física, el consumo de oxígeno sea más alto que en hombres. En posición vertical los volúmenes pulmonares son más altos que en el resto de las posturas. La DLCO es significativamente mayor en posiciones supinas que en posición sentada y vertical, no existiendo diferencias significativas en posición sentada y de pie. Las características antropométricas no son suficientes para explicar las diferencias existentes en la función pulmonar entre diferentes etnias y ponen de manifiesto la importancia de considerar otros factores adicionales a los clásicos antropométricos para su medición

Lung function reference values are traditionally based on anthropometric factors, such as weight, height, sex, and age. FVC and FEV1 decline with age, while volumes and capacities, such as RV and FRC, increase. TLC, VC, RV, FVC and FEV1 are affected by height, since they are proportional to body size. This means that a tall individual will experience greater decrease in lung volumes as they get older. Some variables, such as FRC and ERV, decline exponentially with an increase in weight, to the extent that tidal volume in morbidly obese patients can be close to that of RV. Men have longer airways than women, causing greater specific resistance in the respiratory tract. The increased work of breathing to increase ventilation among women means that their consumption of oxygen is higher than men under similar conditions of physical intensity. Lung volumes are higher when the subject is standing than in other positions. DLCO is significantly higher in supine positions than in sitting or standing positions, but the difference between sitting and standing positions is not significant. Anthropometric characteristics are insufficient to explain differences in lung function between different ethnic groups, underlining the importance of considering other factors in addition to the conventional anthropometric measurements

Factors Affecting Lung Function: A Review of the Literature. / Factores que afectan a la función pulmonar: una revisión bibliográfica.

Lung function reference values are traditionally based on anthropometric factors, such as weight, height, sex, and age. FVC and FEV1 decline with age, while volumes and capacities, such as RV and FRC, increase. TLC, VC, RV, FVC and FEV1 are affected by height, since they are proportional to body size. This means that a tall individual will experience greater decrease in lung volumes as they get older. Some variables, such as FRC and ERV, decline exponentially with an increase in weight, to the extent that tidal volume in morbidly obese patients can be close to that of RV. Men have longer airways than women, causing greater specific resistance in the respiratory tract. The increased work of breathing to increase ventilation among women means that their consumption of oxygen is higher than men under similar conditions of physical intensity. Lung volumes are higher when the subject is standing than in other positions. DLCO is significantly higher in supine positions than in sitting or standing positions, but the difference between sitting and standing positions is not significant. Anthropometric characteristics are insufficient to explain differences in lung function between different ethnic groups, underlining the importance of considering other factors in addition to the conventional anthropometric measurements.

A Machine-to-Machine protocol benchmark for eHealth applications - Use case: Respiratory rehabilitation.

BACKGROUND: M2M (Machine-to-Machine) communications represent one of the main pillars of the new paradigm of the Internet of Things (IoT), and is making possible new opportunities for the eHealth business. Nevertheless, the large number of M2M protocols currently available hinders the election of a suitable solution that satisfies the requirements that can demand eHealth applications. OBJECTIVES: In the first place, to develop a tool that provides a benchmarking analysis in order to objectively select among the most relevant M2M protocols for eHealth solutions. In the second place, to validate the tool with a particular use case: the respiratory rehabilitation. METHODS: A software tool, called Distributed Computing Framework (DFC), has been designed and developed to execute the benchmarking tests and facilitate the deployment in environments with a large number of machines, with independence of the protocol and performance metrics selected. RESULTS: DDS, MQTT, CoAP, JMS, AMQP and XMPP protocols were evaluated considering different specific performance metrics, including CPU usage, memory usage, bandwidth consumption, latency and jitter. The results obtained allowed to validate a case of use: respiratory rehabilitation of chronic obstructive pulmonary disease (COPD) patients in two scenarios with different types of requirement: Home-Based and Ambulatory. CONCLUSIONS: The results of the benchmark comparison can guide eHealth developers in the choice of M2M technologies. In this regard, the framework presented is a simple and powerful tool for the deployment of benchmark tests under specific environments and conditions.

Symptom profiles in the painDETECT Questionnaire in patients with peripheral neuropathic pain stratified according to sensory loss in quantitative sensory testing.

The painDETECT Questionnaire (PDQ) is commonly used as a screening tool to discriminate between neuropathic pain (NP) and nociceptive pain, based on the self-report of symptoms, including pain qualities, numbness, and pain to touch, cold, or heat. However, there are minimal data about whether the PDQ is differentially sensitive to different sensory phenotypes in NP. The aim of the study was to analyze whether the overall PDQ score or its items reflect phenotypes of sensory loss in NP as determined by quantitative sensory testing. An exploratory analysis in the Innovative Medicines Initiative Europain and Neuropain database was performed. Data records of 336 patients identified with NP were grouped into sensory profiles characterized by (1) no loss of sensation, (2) loss of thermal sensation, (3) loss of mechanical sensation, and (4) loss of thermal and mechanical sensation. painDETECT Questionnaire profiles were analyzed in a 2-factor analysis of variance. Patients with loss of thermal sensation (2 and 4) significantly more often reported pain evoked by light touch, and patients with loss of mechanical sensation (3 and 4) significantly more often reported numbness and significantly less often burning sensations and pain evoked by light touch. Although the PDQ was not designed to assess sensory loss, single items reflect thermal and/or mechanical sensory loss at group level, but because of substantial variability, the PDQ does not allow for individual allocation of patients into sensory profiles. It will be useful to develop screening tools according to the current definition of NP.

Altered potassium channel distribution and composition in myelinated axons suppresses hyperexcitability following injury.

Neuropathic pain following peripheral nerve injury is associated with hyperexcitability in damaged myelinated sensory axons, which begins to normalise over time. We investigated the composition and distribution of shaker-type-potassium channels (Kv1 channels) within the nodal complex of myelinated axons following injury. At the neuroma that forms after damage, expression of Kv1.1 and 1.2 (normally localised to the juxtaparanode) was markedly decreased. In contrast Kv1.4 and 1.6, which were hardly detectable in the naïve state, showed increased expression within juxtaparanodes and paranodes following injury, both in rats and humans. Within the dorsal root (a site remote from injury) we noted a redistribution of Kv1-channels towards the paranode. Blockade of Kv1 channels with α-DTX after injury reinstated hyperexcitability of A-fibre axons and enhanced mechanosensitivity. Changes in the molecular composition and distribution of axonal Kv1 channels, therefore represents a protective mechanism to suppress the hyperexcitability of myelinated sensory axons that follows nerve injury.

A distributed approach to alarm management in chronic kidney disease.

This paper presents the feasibility study of using a distributed approach for the management of alarms from chronic kidney disease patients. In a first place, the key issues regarding alarm definition, classification, and prioritization according to available normalization efforts are analyzed for the main scenarios addressed in hemodialysis. Then, the middleware proposed for alarm management is described, which follows the publish/subscribe pattern, and supports the Object Management Group data distribution service (DDS) standard. This standard facilitates the real-time monitoring of the exchanged information, as well as the scalability and interoperability of the solution developed regarding the different stakeholders and resources involved. Finally, the results section shows, through the proof of concept studied, the viability of DDS for the activation of emergency protocols in terms of alarm prioritization and personalization, as well as some remarks about security, privacy, and real-time communication performance.

[Vagus nerve stimulation in patients with migraine]. / Estimulacion del nervio vago en pacientes migrañosos.

INTRODUCTION: Vagus nerve stimulation (VNS) has been approved for the treatment of refractory epilepsy when resective surgery is not possible, and has proved to be highly effective. Series published in the literature suggest a beneficial effect of VNS in the treatment of migraine. AIMS: To determine the degree to which headaches improve in patients with migraine after the placement of VNS to treat refractory epilepsy, and to evaluate what variables are associated with an increased chance of success with this measure. PATIENTS AND METHODS: An observation-based retrospective study was conducted from 1st January 1999 until 31st December 2010. Patients with VNS for refractory epilepsy were contacted by telephone, after selecting those who fulfilled International Headache Society criteria for migraine. Data collected included age, gender, year of placement, age at onset of epilepsy and migraine, improvement of seizures and migraine, presence of migraine with aura and coexistence of anxious-depressive syndrome. Ninety-four patients with VNS were contacted and 13 patients with migraine were selected. RESULTS: Following placement of the VNS, the number of episodes of migraine was seen to decrease by at least 50% in nine patients (69%) (p = 0.004) and there was a drop in the number of episodes of migraine in those patients who had also reduced their epileptic seizures (p = 0.012). No statistically significant associations were observed as regards sex, age, length of disease history, existence of migraine with aura or coexistence of anxious-depressive syndrome. CONCLUSIONS: VNS could have beneficial effects for patients with migraine, especially in cases that are difficult to control. Due to the type of study, these conclusions must be taken with caution. Prospective clinical studies are needed before introducing the technique into daily clinical practice.

TITLE: Estimulacion del nervio vago en pacientes migrañosos.Introduccion. La estimulacion del nervio vago (ENV) esta aprobada para el tratamiento de la epilepsia refractaria cuando no es posible cirugia resectiva, con una eficacia bien establecida. Series publicadas sugieren un efecto beneficioso de la ENV en la migraña. Objetivos. Determinar el grado de mejoria de la cefalea en pacientes migrañosos a los que se les habia implantado una ENV para tratamiento de la epilepsia refractaria y evaluar que variables se asocian a mayor posibilidad de exito con esta medida. Pacientes y metodos. Estudio observacional y retrospectivo desde el 1 de enero de 1999 hasta el 31 de diciembre de 2010. Se contacto telefonicamente con los pacientes con ENV para epilepsia refractaria, seleccionando a aquellos que cumplian los criterios de la Sociedad Internacional de Cefaleas para la migraña. Se recogieron edad, genero, año de implantacion, edad de inicio de la epilepsia y la migraña, mejoria de crisis y de migraña, presencia de aura migrañosa y coexistencia de sindrome ansiosodepresivo. Se contacto con 94 pacientes con ENV y se selecciono a 13 pacientes migrañosos. Resultados. Tras la implantacion de la ENV, se observo una disminucion de al menos el 50% de los episodios de migraña en nueve pacientes (69%) (p = 0,004), asi como una disminucion del numero de episodios de migraña en aquellos pacientes que tambien habian reducido sus crisis epilepticas (p = 0,012). No se observaron asociaciones estadisticamente significativas en cuanto al sexo, edad, tiempo de evolucion, existencia de aura migrañosa o coexistencia de sindrome ansiosodepresivo. Conclusiones. La ENV podria resultar beneficiosa en pacientes con migraña, especialmente en casos de dificil control. Debido al tipo estudio, hay que tomar estas conclusiones con precaucion. Seran necesarios estudios clinicos prospectivos antes de llevarse a la practica clinica habitual.

Estimulación del nervio vago en pacientes migrañosos / Vagus nerve stimulation in patients with migraine

Introducción. La estimulación del nervio vago (ENV) está aprobada para el tratamiento de la epilepsia refractaria cuando no es posible cirugía resectiva, con una eficacia bien establecida. Series publicadas sugieren un efecto beneficioso de la ENV en la migraña. Objetivos. Determinar el grado de mejoría de la cefalea en pacientes migrañosos a los que se les había implantado una ENV para tratamiento de la epilepsia refractaria y evaluar qué variables se asocian a mayor posibilidad de éxito con esta medida. Pacientes y métodos. Estudio observacional y retrospectivo desde el 1 de enero de 1999 hasta el 31 de diciembre de 2010. Se contactó telefónicamente con los pacientes con ENV para epilepsia refractaria, seleccionando a aquéllos que cumplían los criterios de la Sociedad Internacional de Cefaleas para la migraña. Se recogieron edad, género, año de implantación, edad de inicio de la epilepsia y la migraña, mejoría de crisis y de migraña, presencia de aura migrañosa y coexistencia de síndrome ansiosodepresivo. Se contactó con 94 pacientes con ENV y se seleccionó a 13 pacientes migrañosos. Resultados. Tras la implantación de la ENV, se observó una disminución de al menos el 50% de los episodios de migraña en nueve pacientes (69%) (p = 0,004), así como una disminución del número de episodios de migraña en aquellos pacientes que también habían reducido sus crisis epilépticas (p = 0,012). No se observaron asociaciones estadísticamente significativas en cuanto al sexo, edad, tiempo de evolución, existencia de aura migrañosa o coexistencia de síndrome ansiosodepresivo. Conclusiones. La ENV podría resultar beneficiosa en pacientes con migraña, especialmente en casos de difícil control. Debido al tipo estudio, hay que tomar estas conclusiones con precaución. Serán necesarios estudios clínicos prospectivos antes de llevarse a la práctica clínica habitual (AU)

Introduction. Vagus nerve stimulation (VNS) has been approved for the treatment of refractory epilepsy when resective surgery is not possible, and has proved to be highly effective. Series published in the literature suggest a beneficial effect of VNS in the treatment of migraine. Aims. To determine the degree to which headaches improve in patients with migraine after the placement of VNS to treat refractory epilepsy, and to evaluate what variables are associated with an increased chance of success with this measure. Patients and methods. An observation-based retrospective study was conducted from 1st January 1999 until 31st December 2010. Patients with VNS for refractory epilepsy were contacted by telephone, after selecting those who fulfilled International Headache Society criteria for migraine. Data collected included age, gender, year of placement, age at onset of epilepsy and migraine, improvement of seizures and migraine, presence of migraine with aura and coexistence of anxious-depressive syndrome. Ninety-four patients with VNS were contacted and 13 patients with migraine were selected. Results. Following placement of the VNS, the number of episodes of migraine was seen to decrease by at least 50% in nine patients (69%) (p = 0.004) and there was a drop in the number of episodes of migraine in those patients who had also reduced their epileptic seizures (p = 0.012). No statistically significant associations were observed as regards sex, age, length of disease history, existence of migraine with aura or coexistence of anxious-depressive syndrome. Conclusions. VNS could have beneficial effects for patients with migraine, especially in cases that are difficult to control. Due to the type of study, these conclusions must be taken with caution. Prospective clinical studies are needed before introducing the technique into daily clinical practice (AU)