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1.
MMWR Suppl ; 73(3): 1-13, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38713639

RESUMEN

Since 2000, the availability and use of large health care data and related resources for conducting surveillance, research, and evaluations to guide clinical and public health decision-making has increased rapidly. These trends have been related to transformations in health care information technology and public as well as private-sector efforts for collecting, compiling, and supplying large volumes of data. This growing collection of robust and often timely data has enhanced the capability to increase the knowledge base guiding clinical and public health activities and also has increased the need for effective tools to assess the attributes of these resources and identify the types of scientific questions they are best suited to address. This: MMWR supplement presents a standard framework for evaluating large health care data and related resources, including constructs, criteria, and tools that investigators and evaluators can apply and adapt.


Asunto(s)
Recursos en Salud , Humanos , Estados Unidos
2.
J Thromb Thrombolysis ; 55(1): 189-194, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36515793

RESUMEN

The association between thromboembolic events (TE) and COVID-19 infection is not completely understood at the population level in the United States. We examined their association using a large US healthcare database. We analyzed data from the Premier Healthcare Database Special COVID-19 Release and conducted a case-control study. The study population consisted of men and non-pregnant women aged ≥ 18 years with (cases) or without (controls) an inpatient ICD-10-CM diagnosis of TE between 3/1/2020 and 6/30/2021. Using multivariable logistic regression, we assessed the association between TE occurrence and COVID-19 diagnosis, adjusting for demographic factors and comorbidities. Among 227,343 cases, 15.2% had a concurrent or prior COVID-19 diagnosis within 30 days of their index TE. Multivariable regression analysis showed a statistically significant association between a COVID-19 diagnosis and TE among cases when compared to controls (adjusted odds ratio [aOR] 1.75, 95% CI 1.72-1.78). The association was more substantial if a COVID-19 diagnosis occurred 1-30 days prior to index hospitalization (aOR 3.00, 95% CI 2.88-3.13) compared to the same encounter as the index hospitalization. Our findings suggest an increased risk of TE among persons within 30 days of being diagnosed COVID-19, highlighting the need for careful consideration of the thrombotic risk among COVID-19 patients, particularly during the first month following diagnosis.


Asunto(s)
COVID-19 , Tromboembolia , Masculino , Femenino , Adulto , Humanos , Estados Unidos/epidemiología , COVID-19/complicaciones , COVID-19/epidemiología , Estudios de Casos y Controles , Prueba de COVID-19 , Factores de Riesgo , Tromboembolia/epidemiología , Tromboembolia/etiología , Hospitalización , Estudios Retrospectivos
3.
J Hosp Med ; 17(12): 984-989, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36039477

RESUMEN

The disruptions of the coronavirus disease 2019 (COVID-19) pandemic impacted the delivery and utilization of healthcare services with potential long-term implications for population health and the hospital workforce. Using electronic health record data from over 700 US acute care hospitals, we documented changes in admissions to hospital service areas (inpatient, observation, emergency room [ER], and same-day surgery) during 2019-2020 and examined whether surges of COVID-19 hospitalizations corresponded with increased inpatient disease severity and death rate. We found that in 2020, hospitalizations declined by 50% in April, with greatest declines occurring in same-day surgery (-73%). The youngest patients (0-17) experienced largest declines in ER, observation, and same-day surgery admissions; inpatient admissions declined the most among the oldest patients (65+). Infectious disease admissions increased by 52%. The monthly measures of inpatient case mix index, length of stay, and non-COVID death rate were higher in all months in 2020 compared with respective months in 2019.


Asunto(s)
COVID-19 , Pandemias , Humanos , Hospitalización , Servicio de Urgencia en Hospital , Hospitales
4.
J Public Health Manag Pract ; 28(2): 109-115, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-32496404

RESUMEN

CONTEXT: Syndromic surveillance consists of the systematic collection and use of near real-time data about health-related events for situational awareness and public health action. As syndromic surveillance programs continue to adopt new technologies and expand, it is valuable to evaluate these syndromic surveillance systems and practices to ensure that they meet public health needs. OBJECTIVE: This assessment's aim is to provide recent information about syndromic surveillance systems and practice characteristics among a group of state and local health departments. DESIGN/SETTING: Information was obtained between November 2017 and June 2018 through a telephone survey using an Office of Management and Budget-approved standardized data collection tool. Participants were syndromic surveillance staff from each of 31 state and local health departments participating in the National Syndromic Surveillance Program funded by the Centers for Disease Control and Prevention. Questions included jurisdictional experience, data sources and analysis systems used, syndromic system data processing characteristics, data quality verification procedures, and surveillance activities conducted with syndromic data. MEASURES: Practice-specific information such as types of systems and data sources used for syndromic surveillance, data quality monitoring, and uses of data for public health situational awareness (eg, investigating occurrences of or trends in diseases). RESULTS: The survey analysis revealed a wide range of experiences with syndromic surveillance. Participants reported the receipt of data daily or more frequently. Emergency department data were the primary data source; however, other data sources are being integrated into these systems. All health departments routinely monitored data quality. Syndromes of highest priority across the respondents for health events monitoring were influenza-like illness and drug-related syndromes. However, a wide variety of syndromes were reported as priorities across the health departments. CONCLUSION: Overall, syndromic surveillance was relevantly integrated into the public health surveillance infrastructure. The near real-time nature of the data and its flexibility to monitor different types of health-related issues make it especially useful for public health practitioners. Despite these advances, syndromic surveillance capacity, locally and nationally, must continue to evolve and progress should be monitored to ensure that syndromic surveillance systems and data are optimally able to meet jurisdictional needs.


Asunto(s)
Informática en Salud Pública , Vigilancia de Guardia , Centers for Disease Control and Prevention, U.S. , Humanos , Vigilancia de la Población , Administración en Salud Pública , Vigilancia en Salud Pública , Estados Unidos
5.
MMWR Morb Mortal Wkly Rep ; 70(35): 1228-1232, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34473684

RESUMEN

Viral infections are a common cause of myocarditis, an inflammation of the heart muscle (myocardium) that can result in hospitalization, heart failure, and sudden death (1). Emerging data suggest an association between COVID-19 and myocarditis (2-5). CDC assessed this association using a large, U.S. hospital-based administrative database of health care encounters from >900 hospitals. Myocarditis inpatient encounters were 42.3% higher in 2020 than in 2019. During March 2020-January 2021, the period that coincided with the COVID-19 pandemic, the risk for myocarditis was 0.146% among patients diagnosed with COVID-19 during an inpatient or hospital-based outpatient encounter and 0.009% among patients who were not diagnosed with COVID-19. After adjusting for patient and hospital characteristics, patients with COVID-19 during March 2020-January 2021 had, on average, 15.7 times the risk for myocarditis compared with those without COVID-19 (95% confidence interval [CI] = 14.1-17.2); by age, risk ratios ranged from approximately 7.0 for patients aged 16-39 years to >30.0 for patients aged <16 years or ≥75 years. Overall, myocarditis was uncommon among persons with and without COVID-19; however, COVID-19 was significantly associated with an increased risk for myocarditis, with risk varying by age group. These findings underscore the importance of implementing evidence-based COVID-19 prevention strategies, including vaccination, to reduce the public health impact of COVID-19 and its associated complications.


Asunto(s)
COVID-19/complicaciones , Miocarditis/virología , Adolescente , Adulto , Anciano , COVID-19/epidemiología , Bases de Datos Factuales , Femenino , Humanos , Masculino , Registros Médicos , Persona de Mediana Edad , Miocarditis/epidemiología , Medición de Riesgo , Factores de Riesgo , Estados Unidos/epidemiología , Adulto Joven
6.
Cell Rep ; 36(8): 109572, 2021 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34433032

RESUMEN

The dentate gyrus (DG) of the hippocampus plays a key role in memory formation, and it is known to be modulated by septal projections. By performing electrophysiology and optogenetics, we evaluated the role of cholinergic modulation in the processing of afferent inputs in the DG. We show that mature granule cells (GCs), but not adult-born immature neurons, have increased responses to afferent perforant path stimuli upon cholinergic modulation. This is due to a highly precise reconfiguration of inhibitory circuits, differentially affecting Parvalbumin and Somatostatin interneurons, resulting in a nicotinic-dependent perisomatic disinhibition of GCs. This circuit reorganization provides a mechanism by which mature GCs could escape the strong inhibition they receive, creating a window of opportunity for plasticity. Indeed, coincident activation of perforant path inputs with optogenetic release of acetylcholine produces a long-term potentiated response in GCs, essential for memory formation.


Asunto(s)
Acetilcolina/farmacología , Giro Dentado/metabolismo , Interneuronas/metabolismo , Inhibición Neural/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Animales , Ratones , Ratones Transgénicos , Optogenética
7.
MMWR Morb Mortal Wkly Rep ; 70(15): 560-565, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33857068

RESUMEN

Persons from racial and ethnic minority groups are disproportionately affected by COVID-19, including experiencing increased risk for infection (1), hospitalization (2,3), and death (4,5). Using administrative discharge data, CDC assessed monthly trends in the proportion of hospitalized patients with COVID-19 among racial and ethnic groups in the United States during March-December 2020 by U.S. Census region. Cumulative and monthly age-adjusted COVID-19 proportionate hospitalization ratios (aPHRs) were calculated for racial and ethnic minority patients relative to non-Hispanic White patients. Within each of the four U.S. Census regions, the cumulative aPHR was highest for Hispanic or Latino patients (range = 2.7-3.9). Racial and ethnic disparities in COVID-19 hospitalization were largest during May-July 2020; the peak monthly aPHR among Hispanic or Latino patients was >9.0 in the West and Midwest, >6.0 in the South, and >3.0 in the Northeast. The aPHRs declined for most racial and ethnic groups during July-November 2020 but increased for some racial and ethnic groups in some regions during December. Disparities in COVID-19 hospitalization by race/ethnicity varied by region and became less pronounced over the course of the pandemic, as COVID-19 hospitalizations increased among non-Hispanic White persons. Identification of specific social determinants of health that contribute to geographic and temporal differences in racial and ethnic disparities at the local level can help guide tailored public health prevention strategies and equitable allocation of resources, including COVID-19 vaccination, to address COVID-19-related health disparities and can inform approaches to achieve greater health equity during future public health threats.


Asunto(s)
COVID-19/etnología , COVID-19/terapia , Etnicidad/estadística & datos numéricos , Disparidades en el Estado de Salud , Hospitalización/tendencias , Grupos Raciales/estadística & datos numéricos , Adolescente , Adulto , Anciano , Geografía , Humanos , Persona de Mediana Edad , Determinantes Sociales de la Salud , Estados Unidos/epidemiología , Adulto Joven
8.
Curr Biol ; 29(23): 4010-4023.e4, 2019 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-31708392

RESUMEN

Organisms use their sensory systems to acquire information from their environment and integrate this information to produce relevant behaviors. Nevertheless, how sensory information is converted into adequate motor patterns in the brain remains an open question. Here, we addressed this question using two-photon and light-sheet calcium imaging in intact, behaving zebrafish larvae. We monitored neural activity elicited by auditory stimuli while simultaneously recording tail movements. We observed a spatial organization of neural activity according to four different response profiles (frequency tuning curves), suggesting a low-dimensional representation of frequency information, maintained throughout the development of the larvae. Low frequencies (150-450 Hz) were locally processed in the hindbrain and elicited motor behaviors. In contrast, higher frequencies (900-1,000 Hz) rarely induced motor behaviors and were also represented in the midbrain. Finally, we found that the sensorimotor transformations in the zebrafish auditory system are a continuous and gradual process that involves the temporal integration of the sensory response in order to generate a motor behavior.


Asunto(s)
Vías Auditivas/fisiología , Percepción Auditiva , Encéfalo/fisiología , Pez Cebra/fisiología , Animales , Vías Auditivas/crecimiento & desarrollo , Pez Cebra/crecimiento & desarrollo
9.
Curr Biol ; 27(12): 1707-1720.e5, 2017 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-28578928

RESUMEN

From development up to adulthood, the vertebrate brain is continuously supplied with newborn neurons that integrate into established mature circuits. However, how this process is coordinated during development remains unclear. Using two-photon imaging, GCaMP5 transgenic zebrafish larvae, and sparse electroporation in the larva's optic tectum, we monitored spontaneous and induced activity of large neuronal populations containing newborn and functionally mature neurons. We observed that the maturation of newborn neurons is a 4-day process. Initially, newborn neurons showed undeveloped dendritic arbors, no neurotransmitter identity, and were unresponsive to visual stimulation, although they displayed spontaneous calcium transients. Later on, newborn-labeled neurons began to respond to visual stimuli but in a very variable manner. At the end of the maturation period, newborn-labeled neurons exhibited visual tuning curves (spatial receptive fields and direction selectivity) and spontaneous correlated activity with neighboring functionally mature neurons. At this developmental stage, newborn-labeled neurons presented complex dendritic arbors and neurotransmitter identity (excitatory or inhibitory). Removal of retinal inputs significantly perturbed the integration of newborn neurons into the functionally mature tectal network. Our results provide a comprehensive description of the maturation of newborn neurons during development and shed light on potential mechanisms underlying their integration into a functionally mature neuronal circuit.


Asunto(s)
Neurogénesis/fisiología , Plasticidad Neuronal/fisiología , Neuronas/fisiología , Percepción Visual/fisiología , Pez Cebra/fisiología , Animales , Animales Modificados Genéticamente/fisiología
10.
PLoS Comput Biol ; 13(6): e1005526, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28591182

RESUMEN

The development of new imaging and optogenetics techniques to study the dynamics of large neuronal circuits is generating datasets of unprecedented volume and complexity, demanding the development of appropriate analysis tools. We present a comprehensive computational workflow for the analysis of neuronal population calcium dynamics. The toolbox includes newly developed algorithms and interactive tools for image pre-processing and segmentation, estimation of significant single-neuron single-trial signals, mapping event-related neuronal responses, detection of activity-correlated neuronal clusters, exploration of population dynamics, and analysis of clusters' features against surrogate control datasets. The modules are integrated in a modular and versatile processing pipeline, adaptable to different needs. The clustering module is capable of detecting flexible, dynamically activated neuronal assemblies, consistent with the distributed population coding of the brain. We demonstrate the suitability of the toolbox for a variety of calcium imaging datasets. The toolbox open-source code, a step-by-step tutorial and a case study dataset are available at https://github.com/zebrain-lab/Toolbox-Romano-et-al.


Asunto(s)
Potenciales de Acción/fisiología , Señalización del Calcio/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Neuronas/fisiología , Programas Informáticos , Imagen de Colorante Sensible al Voltaje/métodos , Calcio/metabolismo , Rastreo Celular/métodos , Conectoma/métodos , Imagen Molecular/métodos , Neuronas/citología , Lenguajes de Programación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Integración de Sistemas
11.
Cell Rep ; 19(5): 939-948, 2017 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-28467907

RESUMEN

The brain is spontaneously active, even in the absence of sensory stimulation. The functionally mature zebrafish optic tectum shows spontaneous activity patterns reflecting a functional connectivity adapted for the circuit's functional role and predictive of behavior. However, neither the emergence of these patterns during development nor the role of retinal inputs in their maturation has been characterized. Using two-photon calcium imaging, we analyzed spontaneous activity in intact and enucleated zebrafish larvae throughout tectum development. At the onset of retinotectal connections, intact larvae showed major changes in the spatiotemporal structure of spontaneous activity. Although the absence of retinal inputs had a significant impact on the development of the temporal structure, the tectum was still capable of developing a spatial structure associated with the circuit's functional roles and predictive of behavior. We conclude that neither visual experience nor intrinsic retinal activity is essential for the emergence of a spatially structured functional circuit.


Asunto(s)
Retina/fisiología , Colículos Superiores/fisiología , Percepción Visual , Animales , Señalización del Calcio , Estimulación Luminosa , Retina/crecimiento & desarrollo , Retina/metabolismo , Colículos Superiores/crecimiento & desarrollo , Vías Visuales/crecimiento & desarrollo , Vías Visuales/fisiología , Pez Cebra
12.
J Racial Ethn Health Disparities ; 4(2): 213-222, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27059052

RESUMEN

OBJECTIVES: People with disabilities are known to experience disparities in behavioral health risk factors including smoking and obesity. What is unknown is how disability, race/ethnicity, and socioeconomic status combine to affect prevalence of these health behaviors. We assessed the association between race/ethnicity, socioeconomic factors (income and education), and disability on two behavioral health risk factors. METHODS: Data from the 2007-2010 Behavioral Risk Factor Surveillance System were used to determine prevalence of cigarette smoking and obesity by disability status, further stratified by race and ethnicity as well as income and education. Logistic regression was used to determine associations of income and education with the two behavioral health risk factors, stratified by race and ethnicity. RESULTS: Prevalence of disability by race and ethnicity ranged from 10.1 % of Asian adults to 31.0 % of American Indian/Alaska Native (AIAN) adults. Smoking prevalence increased with decreasing levels of income and education for most racial and ethnic groups, with over half of white (52.4 %) and AIAN adults (59.3 %) with less than a high school education reporting current smoking. Education was inversely associated with obesity among white, black, and Hispanic adults with a disability. CONCLUSION: Smoking and obesity varied by race and ethnicity and socioeconomic factors (income and education) among people with disabilities. Our findings suggest that disparities experienced by adults with disabilities may be compounded by disparities associated with race, ethnicity, and socioeconomic factors. This knowledge may help programs in formulating health promotion strategies targeting people at increased risk for smoking and obesity, inclusive of those with disabilities.


Asunto(s)
Personas con Discapacidad/estadística & datos numéricos , Escolaridad , Etnicidad/estadística & datos numéricos , Renta/estadística & datos numéricos , Obesidad/etnología , Fumar/etnología , Adolescente , Adulto , Negro o Afroamericano , Anciano , Asiático , Femenino , Conductas de Riesgo para la Salud , Hispánicos o Latinos , Humanos , Indígenas Norteamericanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores Socioeconómicos , Estados Unidos/epidemiología , Población Blanca , Adulto Joven
14.
Cell Rep ; 17(4): 1098-1112, 2016 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-27760314

RESUMEN

Following moving visual stimuli (conditioning stimuli, CS), many organisms perceive, in the absence of physical stimuli, illusory motion in the opposite direction. This phenomenon is known as the motion aftereffect (MAE). Here, we use MAE as a tool to study the neuronal basis of visual motion perception in zebrafish larvae. Using zebrafish eye movements as an indicator of visual motion perception, we find that larvae perceive MAE. Blocking eye movements using optogenetics during CS presentation did not affect MAE, but tectal ablation significantly weakened it. Using two-photon calcium imaging of behaving GCaMP3 larvae, we find post-stimulation sustained rhythmic activity among direction-selective tectal neurons associated with the perception of MAE. In addition, tectal neurons tuned to the CS direction habituated, but neurons in the retina did not. Finally, a model based on competition between direction-selective neurons reproduced MAE, suggesting a neuronal circuit capable of generating perception of visual motion.


Asunto(s)
Encéfalo/fisiología , Percepción de Movimiento/fisiología , Percepción Visual/fisiología , Pez Cebra/fisiología , Animales , Condicionamiento Psicológico , Movimientos Oculares/fisiología , Efecto Tardío Figurativo/fisiología , Habituación Psicofisiológica , Larva/fisiología , Modelos Biológicos , Modelos Neurológicos , Movimiento , Neuronas/fisiología , Optogenética , Colículos Superiores/fisiología , Cola (estructura animal)
15.
J Acad Nutr Diet ; 116(4): 599-607.e3, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27046061

RESUMEN

BACKGROUND: School breakfast consumption can improve children's nutrition, but the implications of breakfast at school for children's weight remains unclear. OBJECTIVE: The aim of this study was to determine whether receiving breakfast at school is related to changes in children's weight between the fifth and eighth grades, and whether the relationship between school breakfasts and obesity varies for children of different socioeconomic backgrounds. DESIGN: This was a longitudinal study of children observed in the fifth and eighth grades. PARTICIPANTS: Data are from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99, a nationally representative prospective cohort of children in the United States. The analytic sample consisted of 6,495 children interviewed in the fifth and eighth grades. MAIN OUTCOME MEASURE: Standard thresholds from the Centers for Disease Control and Prevention were used to classify children as not obese or obese based on direct-measured height and weight. STATISTICAL ANALYSES PERFORMED: Difference-in-difference propensity score matching and fixed-effect logistic regression models were used to estimate the relationship between receipt of school breakfast and change in obesity between the fifth and eighth grades, adjusting for child, household, and school characteristics. RESULTS: School breakfast receipt was not associated with a change in obesity status between the fifth and eighth grades for children overall (odds ratio=1.31; P=0.129). In the propensity score model, receiving school breakfasts more than doubled the odds of becoming obese (odds ratio=2.31; P=0.0108) for children from families below the federal poverty line compared with children of similar socioeconomic backgrounds who did not regularly receive school breakfasts. CONCLUSIONS: School breakfast receipt was not independently related to obesity for most children. Receiving school breakfasts in the fifth grade may be associated with weight gain between the fifth and eighth grades for children from families below the federal poverty line compared with children of similar socioeconomic status who did not receive breakfasts.


Asunto(s)
Desayuno , Servicios de Alimentación , Obesidad/epidemiología , Instituciones Académicas , Adolescente , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Estudios de Cohortes , Etnicidad , Femenino , Humanos , Modelos Logísticos , Estudios Longitudinales , Masculino , Pobreza , Estudios Prospectivos , Factores Socioeconómicos , Estados Unidos/epidemiología , Aumento de Peso
16.
Development ; 143(11): 2012-24, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27122167

RESUMEN

Taste buds are sensory organs in jawed vertebrates, composed of distinct cell types that detect and transduce specific taste qualities. Taste bud cells differentiate from oropharyngeal epithelial progenitors, which are localized mainly in proximity to the forming organs. Despite recent progress in elucidating the molecular interactions required for taste bud cell development and function, the cell behavior underlying the organ assembly is poorly defined. Here, we used time-lapse imaging to observe the formation of taste buds in live zebrafish larvae. We found that tg(fgf8a.dr17)-expressing cells form taste buds and get rearranged within the forming organs. In addition, differentiating cells move from the epithelium to the forming organs and can be displaced between developing organs. During organ formation, tg(fgf8a.dr17) and type II taste bud cells are displaced in random, directed or confined mode relative to the taste bud they join or by which they are maintained. Finally, ascl1a activity in the 5-HT/type III cell is required to direct and maintain tg(fgf8a.dr17)-expressing cells into the taste bud. We propose that diversity in displacement modes of differentiating cells acts as a key mechanism for the highly dynamic process of taste bud assembly.


Asunto(s)
Movimiento Celular , Organogénesis , Papilas Gustativas/citología , Papilas Gustativas/crecimiento & desarrollo , Pez Cebra/fisiología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Recuento de Células , Diferenciación Celular , Linaje de la Célula , Elementos de Facilitación Genéticos/genética , Larva/citología , Larva/metabolismo , Serotonina/metabolismo , Factores de Transcripción , Proteínas de Pez Cebra/metabolismo
17.
Sci Rep ; 5: 12196, 2015 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-26194888

RESUMEN

Zebrafish larva is a unique model for whole-brain functional imaging and to study sensory-motor integration in the vertebrate brain. To take full advantage of this system, one needs to design sensory environments that can mimic the complex spatiotemporal stimulus patterns experienced by the animal in natural conditions. We report on a novel open-ended microfluidic device that delivers pulses of chemical stimuli to agarose-restrained larvae with near-millisecond switching rate and unprecedented spatial and concentration accuracy and reproducibility. In combination with two-photon calcium imaging and recordings of tail movements, we found that stimuli of opposite hedonic values induced different circuit activity patterns. Moreover, by precisely controlling the duration of the stimulus (50-500 ms), we found that the probability of generating a gustatory-induced behavior is encoded by the number of neurons activated. This device may open new ways to dissect the neural-circuit principles underlying chemosensory perception.


Asunto(s)
Dispositivos Laboratorio en un Chip , Actividad Motora/fisiología , Neuronas/fisiología , Pez Cebra/fisiología , Animales , Conducta Animal , Bulbo Olfatorio/fisiología , Reología , Olfato/fisiología , Gusto/fisiología
18.
Neuron ; 85(5): 1070-85, 2015 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-25704948

RESUMEN

Spontaneous neuronal activity is spatiotemporally structured, influencing brain computations. Nevertheless, the neuronal interactions underlying these spontaneous activity patterns, and their biological relevance, remain elusive. Here, we addressed these questions using two-photon calcium imaging of intact zebrafish larvae to monitor the neuron-to-neuron spontaneous activity fine structure in the tectum, a region involved in visual spatial detection. Spontaneous activity was organized in topographically compact assemblies, grouping functionally similar neurons rather than merely neighboring ones, reflecting the tectal retinotopic map despite being independent of retinal drive. Assemblies represent all-or-none-like sub-networks shaped by competitive dynamics, mechanisms advantageous for visual detection in noisy natural environments. Notably, assemblies were tuned to the same angular sizes and spatial positions as prey-detection performance in behavioral assays, and their spontaneous activation predicted directional tail movements. Therefore, structured spontaneous activity represents "preferred" network states, tuned to behaviorally relevant features, emerging from the circuit's intrinsic non-linear dynamics, adapted for its functional role.


Asunto(s)
Adaptación Fisiológica/fisiología , Red Nerviosa/fisiología , Neuronas/fisiología , Estimulación Luminosa/métodos , Vías Visuales/fisiología , Animales , Animales Modificados Genéticamente , Colículos Superiores/fisiología , Pez Cebra
19.
Front Neural Circuits ; 7: 118, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23874272

RESUMEN

Rett syndrome (RTT) is an X-linked neurodevelopmental disorder and one of the most common causes of mental retardation in affected girls. Other symptoms include a rapid regression of motor and cognitive skills after an apparently early normal development. Sporadic mutations in the transcription factor MECP2 has been shown to be present in more than 90% of the patients and several models of MeCP2-deficient mice have been created to understand the role of this gene. These models have pointed toward alterations in the maintenance of the central nervous system rather than its development, in line with the late onset of the disease in humans. However, the exact functions of MeCP2 remain difficult to delineate and the animal models have yielded contradictory results. Here, we present the first mecp2-null allele mutation zebrafish model. Surprisingly and in contrast to MeCP2-null mouse models, mecp2-null zebrafish are viable and fertile. They present nonetheless clear behavioral alterations during their early development, including spontaneous and sensory-evoked motor anomalies, as well as defective thigmotaxis.


Asunto(s)
Proteína 2 de Unión a Metil-CpG/deficiencia , Proteína 2 de Unión a Metil-CpG/fisiología , Modelos Animales , Actividad Motora/fisiología , Factores de Edad , Animales , Animales Modificados Genéticamente , Femenino , Humanos , Masculino , Proteína 2 de Unión a Metil-CpG/genética , Mutación/genética , Embarazo , Pez Cebra
20.
Artículo en Inglés | MEDLINE | ID: mdl-23576959

RESUMEN

The optical transparency and the small dimensions of zebrafish at the larval stage make it a vertebrate model of choice for brain-wide in-vivo functional imaging. However, current point-scanning imaging techniques, such as two-photon or confocal microscopy, impose a strong limit on acquisition speed which in turn sets the number of neurons that can be simultaneously recorded. At 5 Hz, this number is of the order of one thousand, i.e., approximately 1-2% of the brain. Here we demonstrate that this limitation can be greatly overcome by using Selective-plane Illumination Microscopy (SPIM). Zebrafish larvae expressing the genetically encoded calcium indicator GCaMP3 were illuminated with a scanned laser sheet and imaged with a camera whose optical axis was oriented orthogonally to the illumination plane. This optical sectioning approach was shown to permit functional imaging of a very large fraction of the brain volume of 5-9-day-old larvae with single- or near single-cell resolution. The spontaneous activity of up to 5,000 neurons was recorded at 20 Hz for 20-60 min. By rapidly scanning the specimen in the axial direction, the activity of 25,000 individual neurons from 5 different z-planes (approximately 30% of the entire brain) could be simultaneously monitored at 4 Hz. Compared to point-scanning techniques, this imaging strategy thus yields a ≃20-fold increase in data throughput (number of recorded neurons times acquisition rate) without compromising the signal-to-noise ratio (SNR). The extended field of view offered by the SPIM method allowed us to directly identify large scale ensembles of neurons, spanning several brain regions, that displayed correlated activity and were thus likely to participate in common neural processes. The benefits and limitations of SPIM for functional imaging in zebrafish as well as future developments are briefly discussed.


Asunto(s)
Encéfalo/fisiología , Señalización del Calcio/fisiología , Iluminación/métodos , Neuronas/química , Neuronas/fisiología , Animales , Animales Modificados Genéticamente , Larva , Microscopía Confocal/métodos , Factores de Tiempo , Pez Cebra
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