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Huntington's disease (HD) is a genetic neurodegenerative disease which involves a triad of motor, cognitive and psychiatric disturbances. However, there is great variability in the prominence of each type of symptom across individuals. The neurobiological basis of such variability remains poorly understood but would be crucial for better tailored treatments. Multivariate multimodal neuroimaging approaches have been successful in disentangling these profiles in other disorders. Thus we applied for the first time such approach to HD. We studied the relationship between HD symptom domains and multimodal measures sensitive to grey and white matter structural alterations. Forty-three HD gene carriers (23 manifest and 20 premanifest individuals) were scanned and underwent behavioural assessments evaluating motor, cognitive and psychiatric domains. We conducted a multimodal analysis integrating different structural neuroimaging modalities measuring grey matter volume, cortical thickness and white matter diffusion indices – fractional anisotropy and radial diffusivity. All neuroimaging measures were entered into a linked independent component analysis in order to obtain multimodal components reflecting common inter-subject variation across imaging modalities. The relationship between multimodal neuroimaging independent components and behavioural measures was analysed using multiple linear regression. We found that cognitive and motor symptoms shared a common neurobiological basis, whereas the psychiatric domain presented a differentiated neural signature. Behavioural measures of different symptom domains correlated with different neuroimaging components, both the brain regions involved and the neuroimaging modalities most prominently associated with each type of symptom showing differences. More severe cognitive and motor signs together were associated with a multimodal component consisting in a pattern of reduced grey matter, cortical thickness and white matter integrity in cognitive and motor related networks. In contrast, depressive symptoms were associated with a component mainly characterised by reduced cortical thickness pattern in limbic and paralimbic regions. In conclusion, using a multivariate multimodal approach we were able to disentangle the neurobiological substrates of two distinct symptom profiles in HD: one characterised by cognitive and motor features dissociated from a psychiatric profile. These results open a new view on a disease classically considered as a uniform entity and initiates a new avenue for further research considering these qualitative individual differences. Keywords: Linked ICA, Data fusion, Huntington's disease, Neurodegeneration, Clinical profiles, Structural MRI

Background: Apathy is the neuropsychiatric syndrome that correlates most highly with Huntington's disease progression, and, like early patterns of neurodegeneration, is associated with lesions to cortico-striatal connections. However, due to its multidimensional nature and elusive etiology, treatment options are limited. Objectives: To disentangle underlying white matter microstructural correlates across the apathy spectrum in Huntington's disease. Methods: Forty-six Huntington's disease individuals (premanifest (N = 22) and manifest (N = 24)) and 35 healthy controls were scanned at 3-tesla and underwent apathy evaluation using the short-Problem Behavior Assessment and short-Lille Apathy Rating Scale, with the latter being characterized into three apathy domains, namely emotional, cognitive, and auto-activation deficit. Diffusion tensor imaging was used to study whether individual differences in specific cortico-striatal tracts predicted global apathy and its subdomains. Results: We elucidate that apathy profiles may develop along differential timelines, with the auto-activation deficit domain manifesting prior to motor onset. Furthermore, diffusion tensor imaging revealed that inter-individual variability in the disruption of discrete cortico-striatal tracts might explain the heterogeneous severity of apathy profiles. Specifically, higher levels of auto-activation deficit symptoms significantly correlated with increased mean diffusivity in the right uncinate fasciculus. Conversely, those with severe cognitive apathy demonstrated increased mean diffusivity in the right frontostriatal tract and left dorsolateral prefrontal cortex to caudate nucleus tract. Conclusions: The current study provides evidence that white matter correlates associated with emotional, cognitive, and auto-activation subtypes may elucidate the heterogeneous nature of apathy in Huntington's disease, as such opening a door for individualized pharmacological management of apathy as a multidimensional syndrome in other neurodegenerative disorders. Keywords: Apathy, Diffusion MRI, Huntington's disease, Individual differences, Neurodegeneration, White matter microstructure

El objetivo de este estudio fue analizar los efectos de la Exposición Prenatal a Cocaína (EPC) (0,25 o 50 mg/kg/día) en la conducta emocional de ratones hembras y machos en la adolescencia y la adultez temprana. Se asignaron 27 ratones CD1 hembras gestantes a 3 condiciones experimentales: un grupo control que se le administró solución salina y 2 experimentales a los que se le administró cocaína 25 mg/ kg/día y 50 mg/kg/día, desde el día octavo al veintiunavo de gestación. La conducta emocional de los hijos de estas madres se evaluó en la adolescencia y en la adultez temprana (5.ª y 7.ª semana de edad, respetivamente) por medio del tablero de agujeros y el laberinto en cruz a través de diferentes índices de actividad exploratoria. Los datos se analizaron por medio de MANOVAS y ANOVAS con un valor α de 0.05. La EPC alteró de forma dosis-relacionada la conducta emocional; los sujetos sometidos a EPC 50 mg/kg/día exhibieron mayor ansiedad y temor, en cambio los tratados con EPC 25 mg/kg/día exploraron más, mostrando conductas de alto riesgo, características de la impulsividad e hiperactividad. Los efectos encontrados se mantuvieron en el tiempo, por lo que se concluye que la EPC perturbó permanente y significativamente la emoción.

Abstract Maternal cocaine abuse during pregnancy is associated to neglect, abuse, and mother-child bond disruption, which directly affects infant development; therefore, various neurobehavioral problems of children of drug-dependent parents could be attributed to inadequate maternal behavior or prenatal exposure to drugs. Thus, the aim of this research was to analyze the effects of chronic cocaine administration during pregnancy on postpartum maternal behavior. To do this, 21 CD1 pregnant female mice were randomly assigned for administration of saline solution and cocaine (25 mg/kg/day and 50 mg/kg/day), from day 8 to 21 of gestation. After delivery, for 15 minutes a day, during 20 days, the frequency of occurrence of 16 behavioral patterns of maternal behavior was individually recorded, using an ethogram. Cocaine slightly affected maternal behavior frequency, although it may have affected other parameters, such as latency, duration, and sequence of this behavior.

Based on the analgesic effect of NMDA antagonist receptors, the nociceptive action of the peptide BLMP-101 is evaluated, agonist of NMDA, designed to boost learning/memory. 32 Wistar rats (male and female) were divided into four groups and were injected IP with different BLMP-101 doses (0.01 mg, 0.1 mg, and 0.5 mg) and a control group with physiological saline solution, during 11 days. Daily behavior of animals was registered 15 minutes after injection, and appearance of 26 nociceptive related variables was checked. Data was analyzed by mixed variance with α < 0.05. No important alterations were found. Results suggest that the BLMP-101 peptide does not present nociceptive activity at levels and periodicity used in this study. [ABSTRACT FROM AUTHOR]

Con el objetivo de determinar el aporte de las variables sociodemográficas, psicosociales y de salud, a un modelo de predicción de la demencia en población adulta mayor, se realizó un análisis secundario con los datos del estudio de “Salud, Bienestar y Envejecimiento. Bogotá, 2012”, con 2000 hombres y mujeres mayores de 60 años de áreas urbanas y rurales de Bogotá. Para seleccionar la muestra, se realizó un muestreo probabilístico, polietápico, de conglomerados y estratificado, basado en el censo nacional del 2005. Se utilizó el cuestionario SABE adaptado para Colombia. De acuerdo al nivel de medición de cada variable y la distribución de los datos, se realizaron análisis univariados y bivariados, con la demencia como variable criterio y como predictoras las variables sociodemográficas, de salud; se incluyeron 30 variables. Se encontró que el 40.1% de la varianza de la demencia es explicada por la edad, nivel educativo y socioeconómico, hipertensión, accidente cerebrovascular, depresión, disfuncionalidad motora, fractura de cadera, salud comparada, víctima de atraco, consumo de alcohol, memoria, autorreporte de memoria y memoria comparada. Los hallazgos ofrecen un modelo estadístico que permite la detección de los factores de riesgo para la demencia y el análisis de los potencialmente modificables para su prevención.

To evaluate the effects of caffeinated coffee (150mg/130 ml) on immediate memory and visuomotor planning in university students, an experimental design pretest-posttest with a control group was used. The sample was constituted by 109 students -54 belonged to the decaffeinated coffee group (control) and 55 to the caffeinated coffee group-. Immediate memory, successes, sequencing, traversing and total mistakes, as well as speed and accuracy were evaluated by a test of visuomotor planning (TESEN). Then, randomly and using the double-blind method, participants drank 130ml of coffee without caffeine/with caffeine (control and experimental group, respectively). After 30 minutes, the same indexes were evaluated with different tests. Data were analyzed by repeated measures ANOVA with an alpha = 0.05. Caffeinated coffee (150mg / 130ml) increased immediate memory and decreased traversing mistakes, showing its light ergogenic effects on students of both sexes

Maternal cocaine abuse during pregnancy is associated to neglect, abuse, and mother-child bond disruption, which directlyaffects infant development; therefore, various neurobehavioral problems of children of drug-dependent parents could beattributed to inadequate maternal behavior or prenatal exposure to drugs. Thus, the aim of this research was to analyze theeffects of chronic cocaine administration during pregnancy on postpartum maternal behavior. To do this, 21 CD1 pregnantfemale mice were randomly assigned for administration of saline solution and cocaine (25 mg/kg/day and 50 mg/kg/day), from day 8 to 21 of gestation. After delivery, for 15 minutes a day, during 20 days, the frequency of occurrence of 16 behavioralpatterns of maternal behavior was individually recorded, using an ethogram. Cocaine slightly affected maternal behavior frequency, although it may have affected other parameters, such as latency, duration, and sequence of this behavior.