Temblor ortostático como causa de inestabilidad

Orthostatic tremor (OT) is a neurological disease of unknown aetiology. It is defined by the presence of a 10-20 Hz tremor in the legs while standing still. Symptoms described are dizziness and instability that diminish if the patient sits down or leans on something; drinking small amounts of alcohol significantly reduces OT. Due to the dizziness and/or unsteadiness, these patients are usually referred to the neuro-otology department. We report 4 cases diagnosed with OT. The diagnosis of OT should be considered for patients with instability. The clinical history is a key factor to suspect this entity, and the diagnosis is given by the register of 10-20 Hz contractions on limb electromyography. Treatment for this disease consists of medical treatment; the first option is clonazepam. © 2011 Elsevier España, S.L. All rights reserved

Ganglion cell layer thinning in prodromal Alzheimer's disease defined by amyloid PET

Introduction: The objective of this study was to investigate and compare optic nerve and retinal layers in eyes of patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD) with paired control eyes using optical coherence tomography. Methods: Sixty-three eyes of 34 subjects, 12 eyes with AD and 51 eyes with MCI, positive to 11C-labeled Pittsburgh Compound-B with positron emission tomography (11C-PiB PET/CT), and the same number of sex- and age-paired control eyes underwent optical coherence tomography scanning analyzing retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), Bruch's membrane opening-minimum rim width (BMO-MRW), inner plexiform layer (IPL), outer nuclear layer, and lamina cribrosa (LC). Results: Compared with healthy controls, eyes of patients with positive 11C-PiB PET/CT showed a significant thinning of RNFL (P .131 and P > .721, respectively). Temporal sector GCL, average RNFL, and temporal sector RNFL also exhibited significant thinning when MCI and control eyes were compared (P = .015, P = .005 and P = .050, respectively), and also the greatest area under the curve values (0.689, 0.647, and 0.659, respectively). GCL, IPL, and RNFL tend to be thinner in the AD group compared with healthy controls. Discussion: Our study suggests that RNFL and GCL are useful for potential screening in the early diagnosis of AD. LC and BMO-MRW appear not to be affected by AD.Acknowledgments: P.S.J. was supported by grants from IDIVAL, Instituto de Salud Carlos III (Fondo de Investigacion Sanitario, PI08/0139, PI12/02288, PI16/01652), JPND (DEMTEST PI11/03028) and the CIBERNED program and Siemens Healthineers (Valdecilla Cohort for Memory and Brain Aging). A.C. conducted the statistical analysis

Vídeo-electroencefalografía: una necesidad

El vídeo-EEG es una herramienta diagnóstica habitual. Los avances técnicos de la última década la han simplificado de tal modo que con poco más de un ordenador y una cámara de vídeo pueden conseguirse registros de calidad. Se requiere personal preparado para su ejecución e interpretación. Es muy útil para el diagnóstico de episodios paroxísticos, para la clasificación y caracterización de crisis epilépticas y para la cuantificación de crisis o grafoelementos epileptiformes. Dada la importancia de un diagnóstico exacto, certero, ante un episodio paroxístico, no cabe duda de que esta herramienta debe ser cada vez más asequible para evitar el mal trato a muchos enfermos neurológicos. A pesar del paso de los años, un 20-30% de pacientes diagnosticados de epilepsia no son realmente epilépticos, lo cual sigue siendo excesivo e inaceptable.The video-EEG is a common diagnostic tool nowadays. The technical achievements of the last decade have brought a simplification of the equipment required to obtain good quality recordings, with little more than a computer and a video camera being necessary. However, the medical and technical staff must be well trained to execute and interpret the study. It is very useful in the diagnosis of paroxysmal events, for the classification and characterization of epileptic seizures and to quantify epileptiform discharges. Due to the importance of a correct diagnosis to avoid mistreating many neurological patients, this tool should be accessible to clinicians. In spite of the advances of recent years, 20-30% of patients diagnosed with epilepsy are not really epileptic, a fact that it is excessive and unacceptabl

Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

Variabilidad genética de características morfológicas de maiz nativo (Zea mays L.) en la Península de Yucatán, México

The objective of the research was to study the genetic variability of morphological characteristics of native maize in the Yucatan Peninsula (PY), México. Thirteen recognized native maize accessions were used in the PY under the name of Naál Xóy, Xnúc Naál Blanco, Yellow Rooster, Dzit Bacal, Mejeén Naál, Rosa San Juan, Cháck-Chóp, Teél Cháck, Sáck Teél, San Pableño, Ejú-Creole purple, Xmején Naál Tsitbacal and Clove Chiapas, when sown in June 2017 and 2018, under a randomized complete block design with three replicates. The accessions were exposed to an average temperature of 28 º C from the sowing-physiological maturity, with 1353 and 1962 mm of rainfall accumulated in 2017 and 2018. The results revealed differences (P£0.05) in the morphological variables evaluated: Number of days to male flowering (FM) and female (FF) I present an instability of 12 days to FM and FF, with Naál Xóy and Ejú-Creole purple, and 15 days to physiological maturity with clove Chiapas. A differentiation of 98 and 126 cm in ear height and plant with Eju-Creole purple; 6 and 1.1 cm in ear length and diameter with Xnúc Naál white and Cháck-Chóp, and Yellow Rooster. A variation of 4 rows with Teél Cháck and 17 grains per row with San Pableño; 11 and 74 gr in weight of 100 grains (Xmején Naál Tsitbacal, Rosa San Juan and San Pableño) and grains per ear (Naál Xóy); and a greater difference in performance with Naál Xóy and Dzit Bacal of 3105 kg/ha-1.  El objetivo fue estudiar la variabilidad genética de características morfológicas de maíces nativos en la Península de Yucatán (PY), México. Se utilizaron trece accesiones de maíz nativo reconocidas con el nombre de Naál Xóy, Xnúc Naál Blanco, Gallito Amarillo, Dzit Bacal, Mejeén Naál, Rosa San Juan, Cháck-Chóp, Teél Cháck, Sáck Teél, San Pableño, Ejú-Criollo Morado, Xmején Naál Tsitbacal y Clavo Chiapaneco. Los materiales se establecieron en Junio de 2017 y 2018, en Poxyaxum, Campeche, México, (19° 41´58.4´´ N, 90° 21´03.6´´ W y 30 msnm) bajo un diseño de bloques completos al azar con tres repeticiones. Los resultados revelaron diferencias (P£0.05) en las variables morfológicas evaluadas: número de días a floración masculina (FM) y femenina (FF) presento una inestabilidad de 12 días a FM y FF, con Naál Xóy y Ejú-Criollo Morado, y 15 días a madurez fisiológica con Clavo Chiapaneco. Una diferenciación de 98 y 126 cm en altura de mazorca y planta con Eju-Criollo Morado; 6 y 1.1 cm en longitud y diámetro de mazorca con Xnúc Naál Blanco y Cháck-Chóp, y Gallito Amarillo. Una variación de 4 hileras con Teél Cháck y 17 granos por hilera con San Pableño; 11 y 74 gr en peso de 100 granos (Xmején Naál Tsitbacal, Rosa San Juan y San Pableño) y granos por mazorca (Naál Xóy); y una diferencia mayor en rendimiento con Naál Xóy y Dzit Bacal de 3105 kg.ha-1

Computational classifiers for predicting the short-term course of Multiple sclerosis

Abstract Background The aim of this study was to assess the diagnostic accuracy (sensitivity and specificity) of clinical, imaging and motor evoked potentials (MEP) for predicting the short-term prognosis of multiple sclerosis (MS). Methods We obtained clinical data, MRI and MEP from a prospective cohort of 51 patients and 20 matched controls followed for two years. Clinical end-points recorded were: 1) expanded disability status scale (EDSS), 2) disability progression, and 3) new relapses. We constructed computational classifiers (Bayesian, random decision-trees, simple logistic-linear regression-and neural networks) and calculated their accuracy by means of a 10-fold cross-validation method. We also validated our findings with a second cohort of 96 MS patients from a second center. Results We found that disability at baseline, grey matter volume and MEP were the variables that better correlated with clinical end-points, although their diagnostic accuracy was low. However, classifiers combining the most informative variables, namely baseline disability (EDSS), MRI lesion load and central motor conduction time (CMCT), were much more accurate in predicting future disability. Using the most informative variables (especially EDSS and CMCT) we developed a neural network (NNet) that attained a good performance for predicting the EDSS change. The predictive ability of the neural network was validated in an independent cohort obtaining similar accuracy (80%) for predicting the change in the EDSS two years later. Conclusions The usefulness of clinical variables for predicting the course of MS on an individual basis is limited, despite being associated with the disease course. By training a NNet with the most informative variables we achieved a good accuracy for predicting short-term disability.</p

Vídeo-electroencefalografía: una necesidad

El vídeo-EEG es una herramienta diagnóstica habitual. Los avances técnicos de la última década la han simplificado de tal modo que con poco más de un ordenador y una cámara de vídeo pueden conseguirse registros de calidad. Se requiere personal preparado para su ejecución e interpretación. Es muy útil para el diagnóstico de episodios paroxísticos, para la clasificación y caracterización de crisis epilépticas y para la cuantificación de crisis o grafoelementos epileptiformes. Dada la importancia de un diagnóstico exacto, certero, ante un episodio paroxístico, no cabe duda de que esta herramienta debe ser cada vez más asequible para evitar el mal trato a muchos enfermos neurológicos. A pesar del paso de los años, un 20-30% de pacientes diagnosticados de epilepsia no son realmente epilépticos, lo cual sigue siendo excesivo e inaceptable.The video-EEG is a common diagnostic tool nowadays. The technical achievements of the last decade have brought a simplification of the equipment required to obtain good quality recordings, with little more than a computer and a video camera being necessary. However, the medical and technical staff must be well trained to execute and interpret the study. It is very useful in the diagnosis of paroxysmal events, for the classification and characterization of epileptic seizures and to quantify epileptiform discharges. Due to the importance of a correct diagnosis to avoid mistreating many neurological patients, this tool should be accessible to clinicians. In spite of the advances of recent years, 20-30% of patients diagnosed with epilepsy are not really epileptic, a fact that it is excessive and unacceptabl