Amodal population clock in the primate medial premotor system for rhythmic tapping.

The neural substrate for beat extraction and response entrainment to rhythms is not fully understood. Here we analyze the activity of medial premotor neurons in monkeys performing isochronous tapping guided by brief flashing stimuli or auditory tones. The population dynamics shared the following properties across modalities: the circular dynamics of the neural trajectories form a regenerating loop for every produced interval; the trajectories converge in similar state space at tapping times resetting the clock; and the tempo of the synchronized tapping is encoded in the trajectories by a combination of amplitude modulation and temporal scaling. Notably, the modality induces displacement in the neural trajectories in the auditory and visual subspaces without greatly altering the time-keeping mechanism. These results suggest that the interaction between the medial premotor cortex's amodal internal representation of pulse and a modality-specific external input generates a neural rhythmic clock whose dynamics govern rhythmic tapping execution across senses.

Lisado plaquetario autólogo y su efectividad en pacientes con epicondilitis / Autologous platelet lysate and its effectiveness in patients with epicondylitis

Introducción: La epicondilitis constituye uno de los motivos de consulta más frecuentes tanto en la asistencia primaria como especializada y sin duda alguna, es uno de los problemas que tiene mayor repercusión en la persona que la padece. El tratamiento de las epicondilitis constituye un reto para la medicina debido a enormes implicaciones sanitarias, sociolaborales y el dolor e impotencia funcional que provoca. Objetivo: Evaluar la efectividad del lisado plaquetario autólogo como alternativa de tratamiento en pacientes enfermos con epicondilitis. Método: Se realizó un estudio cuasi experimental analítico longitudinal prospectivo en el que se evaluó el uso de lisado plaquetario autólogo como alternativa de tratamiento en pacientes con epicondilitis. El universo estuvo constituido por los pacientes que acudieron a consulta de Ortopedia y traumatología con el diagnóstico de epicondilitis, durante el periodo comprendido entre octubre de 2014 y julio de 2018. La muestra quedo constituida por 80 pacientes que cumplieron con los criterios de inclusión y exclusión. Resultados: El grupo de edad entre 36-56 años y del sexo femenino son los de mayor representación en padecer esta enfermedad. Las infiltraciones de lisado plaquetario autólogo aportan mejores resultados al convencional y se observa la mayor representación de pacientes que tuvieron una remisión total. Las complicaciones fueron mucho más evidentes en el tratamiento convencional. También es relevante el costo-beneficio del tratamiento con lisado plaquetario autólogo. Conclusiones: El tratamiento con lisado plaquetario autólogo puede ser una alternativa para mejorar la calidad de vida de los pacientes con epicondilitis(AU)

Introduction: Epicondylitis is one of the most frequent reasons for attending consultation in both primary and specialized care; while it is undoubtedly one of the problems with the greatest impact on the person who suffers from it. The managment epicondylitis is a challenge for medicine, due to the enormous health-related and social implications, as well as the pain and functional impotence that it causes. Objective: To assess the effectiveness of autologous platelet lysate as a treatment alternative in patients with epicondylitis. Method: A prospective, longitudinal, analytical and quasiexperimental study was carried out, in which the use of autologous platelet lysate as an alternative treatment in patients with epicondylitis was assessed. The universe consisted of patients who attended the orthopedics and traumatology consultation, during the period between October 2014 and July 2018, with a diagnosis of epicondylitis. The sample was made up of eighty patients who met the inclusion criteria; exclusion criteria were also considered. Results: The age group between 36 and 56 years, together with the female sex, are the most represented with respect to suffering from this disease. Infiltrations of autologous platelet lysate provide better outcomes than the conventional one, while greater representation of remitted patients is observed. Complications were much more evident in conventional treatment. The cost-benefit relationship of treatment with autologous platelet lysate is also relevant. Conclusions: Treatment with autologous platelet lysate can be an alternative to improve the quality of life of patients with epicondylitis(AU)

Faster Recovery of Internal Ophthalmoplegia than External Ophthalmoplegia in a Miller Fisher Variant of Guillain-Barre Syndrome.

We present a case of classic Miller Fisher Syndrome (MFS) variant of Guillain-Barre Syndrome (GBS) with detailed description in the difference between the internal and external ophthalmoplegia. They are different in their onset, duration, and recovery.

A DIY Low-Cost Wireless Wind Data Acquisition System Used to Study an Arid Coastal Foredune.

Environmental studies on coastal dune systems are faced with a considerable cost barrier due to the cost of the instrumentation and sensory equipment required for data collection. These systems play an important role in coastal areas as a protection against erosion and as providers of stability to coastal sedimentary deposits. The DIY (Do-It-Yourself) approach to data acquisition can reduce the cost of these environmental studies. In this paper, a low-cost DIY wireless wind data acquisition system is presented which reduces the cost barrier inherent to these types of studies. The system is deployed for the analysis of the foredune of Maspalomas, an arid dune field situated on the south coast of Gran Canaria (Canary Islands, Spain), for the specific purpose of studying the dynamics of a dune type (tongue dunes), which is typical of this environment. The results obtained can be of interest for the study of these coastal environments at both the local level, for the management of this particular dune field, and at the general level for other similar dune fields around the world.

Multi-frequency and light-avoiding characteristics of deep acoustic layers in the North Atlantic.

This study aimed to add light-avoidance as a categorizing technique for the study of mesopelagic acoustic layers. Data recorded along the 20° W parallel from 20° N to Iceland showed three types of mesopelagic layers: the non-avoiding non-migrant deep scattering layer (NMDSL), which dropped its intensity toward the north, the avoiding migrating fish layers (MDSL), which were more intense at upwelling areas and toward the north, and a secondary deeper NMDSL at the southern part. Light avoidance was only discernible at 18 kHz within the main NMDSL when this layer was intense, suggesting that migrants are barely seen at 38 kHz when other resonant scatterers occupy these depths. These results highlight the importance of employing the 18 kHz frequency from a vessel borne echosounder or lowered echosounders attached to a probe to study gas-bearing migrants.

The amplitude in periodic neural state trajectories underlies the tempo of rhythmic tapping.

Our motor commands can be exquisitely timed according to the demands of the environment, and the ability to generate rhythms of different tempos is a hallmark of musical cognition. Yet, the neuronal underpinnings behind rhythmic tapping remain elusive. Here, we found that the activity of hundreds of primate medial premotor cortices (MPCs; pre-supplementary motor area [preSMA] and supplementary motor area [SMA]) neurons show a strong periodic pattern that becomes evident when their responses are projected into a state space using dimensionality reduction analysis. We show that different tapping tempos are encoded by circular trajectories that travelled at a constant speed but with different radii, and that this neuronal code is highly resilient to the number of participating neurons. Crucially, the changes in the amplitude of the oscillatory dynamics in neuronal state space are a signature of duration encoding during rhythmic timing, regardless of whether it is guided by an external metronome or is internally controlled and is not the result of repetitive motor commands. This dynamic state signal predicted the duration of the rhythmically produced intervals on a trial-by-trial basis. Furthermore, the increase in variability of the neural trajectories accounted for the scalar property, a hallmark feature of temporal processing across tasks and species. Finally, we found that the interval-dependent increments in the radius of periodic neural trajectories are the result of a larger number of neurons engaged in the production of longer intervals. Our results support the notion that rhythmic timing during tapping behaviors is encoded in the radial curvature of periodic MPC neural population trajectories.

Pacientes con retardo de consolidación, infiltrados con lisado plaquetario autólogo / Delayed consolidation patients infiltrated with autologous platelet lysate

Introducción: El retardo de consolidación es una complicación que resulta de un proceso de consolidación ósea anormal. Objetivo: Caracterizar a los pacientes con retardo de consolidación, infiltrados con lisado plaquetario autólogo. Métodos: Se realizó un estudio de casos, observacional, descriptivo, transversal y retrospectivo, en el Hospital General Docente Comandante Pinares, de enero 2008 a diciembre de 2017. Se revisaron 186 historias clínicas y se seleccionaron 80, que cumplían los criterios para el estudio. Se infiltró entre 6 mL de lisado plaquetario autólogo en los focos de fracturas, se evaluó el tiempo de consolidación ósea mediante radiografías seriadas y se registraron las complicaciones. Las variables del estudio fueron: edad, sexo, color de la piel, localizaciones óseas afectadas, sitios anatómicos del hueso, tiempo de consolidación ósea, complicaciones. Se empleó la distribución de frecuencias absoluta y relativa en el análisis de las variables cualitativas y la media aritmética para la variable cuantitativa edad. Para la relación entre variables cualitativas independientes se utilizó la prueba de chi-cuadrado. Resultados: Hubo más frecuencia de retardo de la consolidación en hombres de piel blanca, con edades comprendidas entre 26 y 45 años. Predominó en el tercio inferior de la tibia. El hueso que más tiempo requirió para su consolidación fue la tibia, con más de 16 semanas. No se describen complicaciones asociadas al implante. Conclusiones: El retardo de consolidación continúa siendo una complicación de difícil manejo. Es frecuente en hombres jóvenes y blancos. El lisado plaquetario autólogo es un buen coadyuvante en el tratamiento de esta complicación(AU)

Introduction: The delay of consolidation is a complication that results from an abnormal bone consolidation process. Objective: To characterize patients with delayed consolidation infiltrated with autologous platelet lysate. Methods: An observational, descriptive, cross-sectional and retrospective case study was conducted at Comandante Pinares General Teaching Hospital, from January 2008 to December 2017. One hundred eighty six (186) medical records were reviewed and eighty (80) were selected, since they met the study criteria. 6 mL of autologous platelet lysate was infiltrated in the foci of fractures. Serial radiographs were used to assess the bone healing time and complications were recorded. The variables of the study were age, sex, color of the skin, affected bone locations, anatomical sites of the bone, time of bone consolidation, complications. The distribution of absolute and relative frequencies was used in the analysis of qualitative variables and arithmetic mean for the quantitative age variable. Chi-square test was used for the relationship between independent qualitative variables. Results: The delayed consolidation was more frequency in white men, aged between 26 and 45 years. It predominated in the lower third of the tibia. Tibia was the bone that required more time for consolidation, more than 16 weeks. No complications associated with the implant are described. Conclusions: The delayed consolidation continues being a complication of difficult treatment. It is frequent in young and white men. The autologous platelet lysate is a good adjuvant in the treatment of this complication(AU)

Introduction: Le retard de consolidation est une complication résultant d'un processus de consolidation osseuse anormal.Objectif: Caractériser les patients atteints de retard de consolidation qui sont traités par infiltration de lysat plaquettaire autologue. Méthodes: Une étude observationnelle, descriptive, transversale et rétrospective a été réalisée à l'hôpital général universitaire Comandante Pinares, depuis janvier 2008 jusqu'à décembre 2017. Sur 186 dossiers médicaux révisés, on a sélectionné 80 respectant les critères d'inclusion de l'étude. Six millilitres de lysat plaquettaire autologue ont été injectés dans les foyers des fractures ; le temps de consolidation osseuse a été estimé par des radiographies en série, et les complications ont été enregistrées. On a utilisé des variables telles que l'âge, le sexe, la couleur de la peau, les localisations osseuses affectées, le site anatomique de l'os, le temps de consolidation osseuse, et les complications. On a employé la distribution de fréquences absolue et relative pour l'analyse des variables qualitatives et la moyenne d'âge, tandis que pour la relation entre les variables qualitatives indépendantes on a utilisé le test du chi-carré. Résultats: Le retard de consolidation a été beaucoup plus fréquent chez les hommes blancs entre 26 et 45 ans. Le tiers inférieur du tibia a été touché en prédominance. L'os qui a exigé beaucoup plus de temps de consolidation a été le tibia (plus de seize semaines). Des complications associées à l'implant n'ont pas été décrites. Conclusions: Le retard de consolidation demeure une complication difficile à traiter. Il est fréquemment observé chez les hommes jeunes et blancs. Le lysat plaquettaire autologue est un bon adjuvant dans le traitement de cette complication(AU)

Predictive rhythmic tapping to isochronous and tempo changing metronomes in the nonhuman primate.

Beat entrainment is the ability to entrain one's movements to a perceived periodic stimulus, such as a metronome or a pulse in music. Humans have a capacity to predictively respond to a periodic pulse and to dynamically adjust their movement timing to match the varying music tempos. Previous studies have shown that monkeys share some of the human capabilities for rhythmic entrainment, such as tapping regularly at the period of isochronous stimuli. However, it is still unknown whether monkeys can predictively entrain to dynamic tempo changes like humans. To address this question, we trained monkeys in three tapping tasks and compared their rhythmic entrainment abilities with those of humans. We found that, when immediate feedback about the timing of each movement is provided, monkeys can predictively entrain to an isochronous beat, generating tapping movements in anticipation of the metronome pulse. This ability also generalized to a novel untrained tempo. Notably, macaques can modify their tapping tempo by predicting the beat changes of accelerating and decelerating visual metronomes in a manner similar to humans. Our findings support the notion that nonhuman primates share with humans the ability of temporal anticipation during tapping to isochronous and smoothly changing sequences of stimuli.

Validación del Cuestionario de Intención Emprendedora en una muestra de estudiantes universitarios de Colombia / Validation of the Entrepreneurial Intention Questionnaire in a Sample of University Students from Colombia

RESUMEN Este artículo presenta la validación del Cuestionario de Intención Emprendedora (CIE) en Colombia. Este cuestionario, desarrollado y validado en España (Rueda, Moriano, & Liñán, 2015), se enmarca dentro de la Teoría de la Acción Planificada (TAI, Ajzen, 1991). La TAP resulta en la actualidad el modelo más ampliamente utilizado para predecir las intenciones emprendedoras. Con una muestra de 316 estudiantes universitarios colombianos, el modelado de ecuaciones estructurales confirma que el CIE tiene una alta fiabilidad y validez predictiva sobre la intención emprendedora. Disponer de escalas de medida fiables y validadas en distintos contextos culturales permite las comparaciones entre distintas entidades y/o para una misma entidad en diferentes momentos (por ejemplo, antes y después de impartir un curso orientado al emprendimiento). Un mejor conocimiento de los antecedentes psicosociales (actitudes hacia el emprendimiento, norma subjetiva y autoeficacia emprendedora) que conducen a jóvenes universitarios a emprender puede contribuir a un diseño más adecuado de los programas de formación emprendedora que se están impulsando en muchas universidades y desde otro tipo de instituciones.

ABSTRACT This paper presents the validation of the Entrepreneurial Intention Questionnaire (EIQ) in Colombia. This questionnaire, developed and validated in Spain (Rueda, Moriano, & Linân, 2015), draws on the Theory of Planned Behaviour (TPB, Ajzen, 1991). The TPB is the most widely used model for predicting entrepreneurial intention nowadays. With a sample of 316 Colombian university students, the results of the structural equation modeling confirm that the EIQ has a high reliability and predictive validity of entrepreneurial intentions. The availability of reliable measurement scales validated in different cultural contexts allows comparisons among institutions and/or within an institution along the time (e.g. before and after a course on entrepreneurship). A deep understanding of the psychosocial antecedents (i.e. attitudes toward entrepreneurship, subjective norms, and entrepreneurial self-efficacy) that lead young university students to become entrepreneurs might contribute to a better design of the entrepreneurship education programmes that are being developed from universities and other institutions.

Enfermedad por arañazo de gato / Cat scratch disease

La enfermedad por arañazo de gato es una infección causada por la bacteria bartonella henselae. Se caracteriza desde el punto de vista clínico por linfadenopatía regional autolimitada, acompañada de fiebre y otros síntomas generales. Se reporta una paciente de 42 años de edad que inició con adenopatías submandibulares en regiones laterales del cuello acompañado de febrículas de 37 °C de 4 semanas de evolución, que aumentan de tamaño. Como diagnóstico diferencial se planteó un proceso linfoproliferativo, indicándose realizar una citología por aspiración por aguja fina de las lesiones, el resultado informa linfadenitis reactiva inespecífica, siendo no concluyente para diagnóstico, por lo que se hace exéresis de un ganglio del cuello. El estudio histopatológico mostró la formación de granulomas, que coalecen y forman (procesos estrellados), es decir, acúmulos irregulares centrales de macrófagos activos y en desintegración, rodeados por un ribete llamativo de macrófagos epitelioides en empalizados.

Cat scratch disease is an infection caused by the bacterium Bartonella henselae. From a clinical point of view it is characterized by regional self-limited lymphadenopathy, accompanied by fever and other general symptoms. A report is presented of a 42-year-old female patient who started out with submandibular adenopathies of increasing size in lateral regions of the neck and 37ºC low-grade fever of 4 weeks of evolution. A lymphoproliferative process was established as differential diagnosis, and fine-needle aspiration cytology of the lesions was indicated. The result was nonspecific reactive lymphadenitis, not conclusive for diagnosis. Therefore, exeresis was performed of a neck ganglion. Histopathological examination revealed the formation of granulomas which coalesce into star-shaped structures, i.e. irregular central accumulations of active and disintegrating macrophages surrounded by a distinct border of palisading epithelioid macrophages.

Enfermedad por arañazo de gato / Cat scratch disease

La enfermedad por arañazo de gato es una infección causada por la bacteria bartonella henselae. Se caracteriza desde el punto de vista clínico por linfadenopatía regional autolimitada, acompañada de fiebre y otros síntomas generales. Se reporta una paciente de 42 años de edad que inició con adenopatías submandibulares en regiones laterales del cuello acompañado de febrículas de 37 °C de 4 semanas de evolución, que aumentan de tamaño. Como diagnóstico diferencial se planteó un proceso linfoproliferativo, indicándose realizar una citología por aspiración por aguja fina de las lesiones, el resultado informa linfadenitis reactiva inespecífica, siendo no concluyente para diagnóstico, por lo que se hace exéresis de un ganglio del cuello. El estudio histopatológico mostró la formación de granulomas, que coalecen y forman (procesos estrellados), es decir, acúmulos irregulares centrales de macrófagos activos y en desintegración, rodeados por un ribete llamativo de macrófagos epitelioides en empalizados(AU)

Cat scratch disease is an infection caused by the bacterium Bartonella henselae. From a clinical point of view it is characterized by regional self-limited lymphadenopathy, accompanied by fever and other general symptoms. A report is presented of a 42-year-old female patient who started out with submandibular adenopathies of increasing size in lateral regions of the neck and 37ºC low-grade fever of 4 weeks of evolution. A lymphoproliferative process was established as differential diagnosis, and fine-needle aspiration cytology of the lesions was indicated. The result was nonspecific reactive lymphadenitis, not conclusive for diagnosis. Therefore, exeresis was performed of a neck ganglion. Histopathological examination revealed the formation of granulomas which coalesce into star-shaped structures, i.e. irregular central accumulations of active and disintegrating macrophages surrounded by a distinct border of palisading epithelioid macrophages(AU)

Recording extracellular neural activity in the behaving monkey using a semichronic and high-density electrode system.

We describe a technique to semichronically record the cortical extracellular neural activity in the behaving monkey employing commercial high-density electrodes. After the design and construction of low cost microdrives that allow varying the depth of the recording locations after the implantation surgery, we recorded the extracellular unit activity from pools of neurons at different depths in the presupplementary motor cortex (pre-SMA) of a rhesus monkey trained in a tapping task. The collected data were processed to classify cells as putative pyramidal cells or interneurons on the basis of their waveform features. We also demonstrate that short time cross-correlogram occasionally yields unit pairs with high short latency (<5 ms), narrow bin (<3 ms) peaks, indicative of monosynaptic spike transmission from pre- to postsynaptic neurons. These methods have been verified extensively in rodents. Finally, we observed that the pattern of population activity was repetitive over distinct trials of the tapping task. These results show that the semichronic technique is a viable option for the large-scale parallel recording of local circuit activity at different depths in the cortex of the macaque monkey and other large species.

Sensorimotor neural dynamics during isochronous tapping in the medial premotor cortex of the macaque.

We determined the response properties of neurons in the primate medial premotor cortex that were classified as sensory or motor during isochronous tapping to a visual or auditory metronome, using different target intervals and three sequential elements in the task. The cell classification was based on a warping transformation, which determined whether the cell activity was statistically aligned to sensory or motor events, finding a large proportion of cells classified as sensory or motor. Two distinctive clusters of sensory cells were observed, i.e. one cell population with short response-onset latencies to the previous stimulus, and another that was probably predicting the occurrence of the next stimuli. These cells were called sensory-driven and stimulus-predicting neurons, respectively. Sensory-driven neurons showed a clear bias towards the visual modality and were more responsive to the first stimulus, with a decrease in activity for the following sequential elements of the metronome. In contrast, stimulus-predicting neurons were bimodal and showed similar response profiles across serial-order elements. Motor cells showed a consecutive activity onset across discrete neural ensembles, generating a rapid succession of activation patterns between the two taps defining a produced interval. The cyclical configuration in activation profiles engaged more motor cells as the serial-order elements progressed across the task, and the rate of cell recruitment over time decreased as a function of the target interval. Our findings support the idea that motor cells were responsible for the rhythmic progression of taps in the task, gaining more importance as the trial advanced, while, simultaneously, the sensory-driven cells lost their functional impact.

Neurophysiology of timing in the hundreds of milliseconds: multiple layers of neuronal clocks in the medial premotor areas.

The precise quantification of time in the subsecond scale is critical for many complex behaviors including music and dance appreciation/execution, speech comprehension/articulation, and the performance of many sports. Nevertheless, its neural underpinnings are largely unknown. Recent neurophysiological experiments from our laboratory have shown that the cell activity in the medial premotor areas (MPC) of macaques can represent different aspects of temporal processing during a synchronization-continuation tapping task (SCT). In this task the rhythmic behavior of monkeys was synchronized to a metronome of isochronous stimuli in the hundreds of milliseconds range (synchronization phase), followed by a period where animals internally temporalized their movements (continuation phase). Overall, we found that the time-keeping mechanism in MPC is governed by different layers of neural clocks. Close to the temporal control of movements are two separate populations of ramping cells that code for elapsed or remaining time for a tapping movement during the SCT. Thus, the sensorimotor loops engaged during the task may depend on the cyclic interplay between two neuronal chronometers that quantify in their instantaneous discharge rate the time passed and the remaining time for an action. In addition, we found MPC neurons that are tuned to the duration of produced intervals during the rhythmic task, showing an orderly variation in the average discharge rate as a function of duration. All the tested durations in the subsecond scale were represented in the preferred intervals of the cell population. Most of the interval-tuned cells were also tuned to the ordinal structure of the six intervals produced sequentially in the SCT. Hence, this next level of temporal processing may work as the notes of a musical score, providing information to the timing network about what duration and ordinal element of the sequence are being executed. Finally, we describe how the timing circuit can use a dynamic neural representation of the passage of time and the context in which the intervals are executed by integrating the time-varying activity of populations of cells. These neural population clocks can be defined as distinct trajectories in the multidimensional cell response-space. We provide a hypothesis of how these different levels of neural clocks can interact to constitute a coherent timing machine that controls the rhythmic behavior during the SCT.

Interval tuning in the primate medial premotor cortex as a general timing mechanism.

The precise quantification of time during motor performance is critical for many complex behaviors, including musical execution, speech articulation, and sports; however, its neural mechanisms are primarily unknown. We found that neurons in the medial premotor cortex (MPC) of behaving monkeys are tuned to the duration of produced intervals during rhythmic tapping tasks. Interval-tuned neurons showed similar preferred intervals across tapping behaviors that varied in the number of produced intervals and the modality used to drive temporal processing. In addition, we found that the same population of neurons is able to multiplex the ordinal structure of a sequence of rhythmic movements and a wide range of durations in the range of hundreds of milliseconds. Our results also revealed a possible gain mechanism for encoding the total number of intervals in a sequence of temporalized movements, where interval-tuned cells show a multiplicative effect of their activity for longer sequences of intervals. These data suggest that MPC is part of a core timing network that uses interval tuning as a signal to represent temporal processing in a variety of behavioral contexts where time is explicitly quantified.