Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71.366
Filtrar
1.
Adv Exp Med Biol ; 1131: 881-900, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646538

RESUMO

Drosophila melanogaster, colloquially known as the fruit fly, is one of the most commonly used model organisms in scientific research. Although the final architecture of a fly and a human differs greatly, most of the fundamental biological mechanisms and pathways controlling development and survival are conserved through evolution between the two species. For this reason, Drosophila has been productively used as a model organism for over a century, to study a diverse range of biological processes, including development, learning, behavior and aging. Ca2+ signaling comprises complex pathways that impact on virtually every aspect of cellular physiology. Within such a complex field of study, Drosophila offers the advantages of consolidated molecular and genetic techniques, lack of genetic redundancy and a completely annotated genome since 2000. These and other characteristics provided the basis for the identification of many genes encoding Ca2+ signaling molecules and the disclosure of conserved Ca2+ signaling pathways. In this review, we will analyze the applications of Ca2+ imaging in the fruit fly model, highlighting in particular their impact on the study of normal brain function and pathogenesis of neurodegenerative diseases.


Assuntos
Cálcio , Drosophila melanogaster , Animais , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Cálcio/metabolismo , Drosophila melanogaster/fisiologia , Humanos , Modelos Animais
2.
Adv Exp Med Biol ; 1175: 45-91, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583584

RESUMO

Astrocytes are principal cells responsible for maintaining the brain homeostasis. Additionally, these glial cells are also involved in homocellular (astrocyte-astrocyte) and heterocellular (astrocyte-other cell types) signalling and metabolism. These astroglial functions require an expression of the assortment of molecules, be that transporters or pumps, to maintain ion concentration gradients across the plasmalemma and the membrane of the endoplasmic reticulum. Astrocytes sense and balance their neurochemical environment via variety of transmitter receptors and transporters. As they are electrically non-excitable, astrocytes display intracellular calcium and sodium fluctuations, which are not only used for operative signalling but can also affect metabolism. In this chapter we discuss the molecules that achieve ionic gradients and underlie astrocyte signalling.


Assuntos
Astrócitos/fisiologia , Encéfalo/fisiologia , Transdução de Sinais , Cálcio , Homeostase , Humanos , Bombas de Íon/fisiologia , Neuroglia , Receptores de Neurotransmissores/fisiologia , Sódio
3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 810-817, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31631630

RESUMO

As a complex system, the topology of human's brain network has an important effect on further study of brain's structural and functional mechanism. Graph theory, a kind of sophisticated analytic strategies, is widely used for analyzing complex brain networks effectively and comparing difference of topological structure alteration in normal development and pathological condition. For the purpose of using this analysis methodology efficiently, it is necessary to develop graph-based visualization software. Thus, we developed VisConnectome, which displays analysis results of the brain network friendly and intuitively. It provides an original graphical user interface (GUI) including the tool window, tool bar and innovative double slider filter, brain region bar, runs in any Windows operating system and doesn't rely on any platform such as Matlab. When importing the user-defined script file that initializes the brain network, VisConnectome abstracts the brain network to the ball-and-stick model and render it. VisConnectome allows a series of visual operations, such as identifying nodes and connection, modifying properties of nodes and connection such as color and size with the color palette and size double slider, imaging the brain regions, filtering the brain network according to its size property in a specific domain as simplification and blending with the brain surface as a context of the brain network. Through experiment and analysis, we conclude that VisConnectome is an effective visualization software with high speed and quality, which helps researchers to visualize and compare the structural and functional brain networks flexibly.


Assuntos
Encéfalo/fisiologia , Conectoma , Software , Humanos
4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 856-861, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31631636

RESUMO

Brain-computer interface (BCI) provides a direct communicating and controlling approach between the brain and surrounding environment, which attracts a wide range of interest in the fields of brain science and artificial intelligence. It is a core to decode the electroencephalogram (EEG) feature in the BCI system. The decoding efficiency highly depends on the feature extraction and feature classification algorithms. In this paper, we first introduce the commonly-used EEG features in the BCI system. Then we introduce the basic classical algorithms and their advanced versions used in the BCI system. Finally, we present some new BCI algorithms proposed in recent years. We hope this paper can spark fresh thinking for the research and development of high-performance BCI system.


Assuntos
Algoritmos , Interfaces Cérebro-Computador , Eletroencefalografia , Reconhecimento Automatizado de Padrão , Encéfalo/fisiologia , Humanos
5.
Medicina (B Aires) ; 79 Suppl 3: 29-32, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31603840

RESUMO

Recent studies have demonstrated that while we are sleeping, our brain is very busy processing all information we have acquired along the day. Lack of sleep has shown to produce deficits in memory consolidation and plays an important role in brain development and brain plasticity in the several developmental stages of the human brain. At the cellular level, circadian cycles coordinate complex mechanism that "turn on and off" genes and cellular structures regulating individual cell functions to impact global organ and systems physiological activities. At the end a perfect and coordinated equilibrium in the mental, emotional and physiological is the goal of this complex process. Sleep impacts memory, learning, mood, behavior, immunological responses, metabolism, hormone levels, digestive process and many more physiological functions. We present a review of three basic aspects related with sleep: a. brain electrical activity during the sleep and neuroanatomic correlation with mechanism related with memory and learning; b. circadian cycles and impact in several physiological systems; c some examples of clinical disorders associated with sleep disorders and impact in learning and memory.


Assuntos
Ritmo Circadiano/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Plasticidade Neuronal/fisiologia , Sono/fisiologia , Encéfalo/fisiologia , Emoções/fisiologia , Humanos , Transtornos do Sono-Vigília/fisiopatologia
6.
Brain Nerve ; 71(9): 993-1002, 2019 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-31506401

RESUMO

Joint attention behaviors involve sharing attention with others to an object or event by means of eye-gazing or pointing, which form the common basis for communication. There are two types of these behaviors: responding to joint attention (RJA) and initiating joint attention (IJA). RJA is the ability to follow the gaze of others, suggesting reception of a social signal from others; IJA is the ability to voluntarily direct the attention of others, to share the experience of an object or event, suggesting transmission of a social signal to others. Infants experience these roles (as signal receiver and signal transmitter) throughout the first year of life and learn social cognitive skills. Recent neuroimaging studies indicate that joint attention is supported by widely distributed neural systems with nodes in the dorsomedial prefrontal cortex, the orbitofrontal cortex and insula, the anterior and posterior cingulate cortex, the superior temporal cortex, the precuneus and parietal cortex, and the amygdala and striatum.


Assuntos
Atenção , Encéfalo/fisiologia , Comportamento Social , Córtex Cerebral , Humanos , Lactente , Lobo Parietal , Córtex Pré-Frontal , Lobo Temporal
7.
Nat Neurosci ; 22(10): 1536-1543, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31477899

RESUMO

Activity-dependent synaptic plasticity has since long been proposed to represent the subcellular substrate of learning and memory, one of the most important behavioral processes through which we adapt to our environment. Despite the undisputed importance of synaptic plasticity for brain function, its exact contribution to learning processes in the context of cellular and connectivity modifications remains obscure. Causally bridging synaptic and behavioral modifications indeed remains limited by the available tools to measure and control synaptic strength and plasticity in vivo under behaviorally relevant conditions. After a brief summary of the current state of knowledge of the links between synaptic plasticity and learning, we will review and discuss the available and desired tools to progress in this endeavor.


Assuntos
Aprendizagem/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Encéfalo/citologia , Encéfalo/fisiologia , Humanos , Vias Neurais/citologia , Vias Neurais/fisiologia
8.
Adv Gerontol ; 32(3): 383-389, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31512425

RESUMO

This paper presents findings of the comparative computer analysis of brain bioelectrical activity (EEG) in three groups of rural population, which include: long-livers, their close relatives, and representatives of families without records of longevity (the latter was conventionally accepted as the «control group¼). Registration of EEG was carried out in conditions of quiet wakefulness with eyes closed. For each group, the average spectral power, frequency characteristics, EEG indices in the ranges of δ-, θ-, α- and ß-rhythms were estimated. The results have revealed the increased ascending effects of the synchronizing link and the weakening of the activating assumptions of non-specific brain systems in long-livers, which we consider as reflection of inhibitory mechanisms which are required to replenish the mobilization resources. With regard to the group of relatives, there were revealed a smaller percentage of δ-rhythm and a greater severity of the α-rhythm index in the temporal areas, as compared to the control group, which is indicative of a more optimal level of processes responsible for memory, integration of afferent (auditory and visual) information and harmonization of the emotional background.


Assuntos
Encéfalo , Eletroencefalografia , Longevidade , Ritmo alfa , Encéfalo/fisiologia , Ritmo Delta , Humanos , População Rural/estatística & dados numéricos
9.
Nat Biotechnol ; 37(9): 1007-1012, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31477925

RESUMO

Periodically throughout history developments from adjacent fields of science and technology reach a tipping point where together they produce unparalleled advances, such as the Allen Brain Atlas and the Human Genome Project. Today, research focused at the interface between the nervous system and electronics is not only leading to advances in fundamental neuroscience, but also unlocking the potential of implants capable of cellular-level therapeutic targeting. Ultimately, these personalized electronic therapies will provide new treatment modalities for neurodegenerative and neuropsychiatric illness; powerful control of prosthetics for restorative function in degenerative diseases, trauma and amputation; and even augmentation of human cognition. Overall, we believe that emerging advances in tissue-like electronics will enable minimally invasive devices capable of establishing a stable long-term cellular neural interface and providing long-term treatment for chronic neurological conditions.


Assuntos
Encéfalo/fisiologia , Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/terapia , Medicina de Precisão , Fenômenos Eletrofisiológicos , Humanos , Nanotecnologia
13.
Adv Exp Med Biol ; 1155: 3-11, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468381

RESUMO

Taurine content in an older brain is decreased compared to a younger brain and is associated with cognitive deficits. It is not yet known whether the decrease in taurine content is associated with decreased expression of taurine inflow mediating transporters during the aging process. In this study, we investigated whether aging affects taurine transporter and glycine transporter 1 expression in the brain cortex of the mouse. Taurine and glycine transporter expression was compared in the brain cortex of C57BL/6 mice at different ages (2, 12, and 24 months) and to age-matched NLRP3 inflammasome knockout mice. In wild type mice, taurine transporter (TauT) expression in the brain cortex of 12- or 24-month-old mice did not significantly differ from TauT expression in 2-month-old mice. Moreover, TauT expression in the brain cortex of 12- or 24-month-old mice did not significantly differ from age-matched NLRP3 KO mice. This result indirectly suggests that TauT expression may be not affected by aging or age-induced inflammation. In addition, glycine transporter expression was similar to the TauT expression pattern. In conclusion, aging and age-related inflammation might not significantly affect taurine and glycine transporter expression in aged mice. Thus, the decrease of taurine content in an older brain, which is associated with cognitive deficits, may not be significantly related to altered taurine and glycine transporter expression.


Assuntos
Envelhecimento , Encéfalo/fisiologia , Glicoproteínas de Membrana/fisiologia , Proteínas de Membrana Transportadoras/fisiologia , Taurina/análise , Animais , Camundongos , Camundongos Endogâmicos C57BL
14.
Top Magn Reson Imaging ; 28(4): 189-196, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31385898

RESUMO

Functional MRI (fMRI) is currently used for pre-surgical planning, but is often limited to information on the motor and language systems. Resting state fMRI can provide more information on multiple other networks to the neurosurgeon and neuroradiologist; however, currently, these networks are not well known among clinicians. The purpose of this manuscript is to provide an introduction to these networks for the clinician and to discuss how they could be used in the future for precise and individualized surgical planning. We provide a short introduction to resting state fMRI and discuss multiple currently accepted resting state networks with a review of the literature. We review the characteristics and function of multiple somatosensory, association, and other networks. We discuss the concept of critical nodes in the brain and how the neurosurgeon can use this information to individually customize patient care. Although further research is necessary, future application of pre-surgical planning will require consideration of networks other than just motor and language in order to minimize post-surgical morbidity and customize patient care.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Imagem por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Humanos , Linguagem , Atividade Motora , Descanso/fisiologia
15.
Gene ; 717: 143998, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31381951

RESUMO

Eid1 is a member of the EID protein family, which regulates differentiation, transcription and acetyltransferase activity. Accumulating evidence suggests that Eid1 is relevant to neurological disorder, but the main function of Eid1 is still unclear, especially in the brain. To better understand this issue, we generated Eid1-knockout (Eid1-KO) mice and profiled its gene expression changes in the brain by RNA sequencing. This study identified 2531 genes differentially expressed in Eid1-KO mice compared with the wild-type, then qRT-PCR verification demonstrated that the transcriptomic data are reliable. By protein-protein interaction cluster analysis, 'regulation of cell proliferation' were unexpectedly discovered as important Eid1 functions. We then isolated neural progenitor cells (NPCs) and showed that the number of neurospheres and the proliferation rate of Eid1-KO NPCs were obviously lower than that in the control group, furthermore, CCK-8 and immunofluorescence assay clearly demonstrated that the Eid1-KO NPCs showed significantly less cell proliferation than the control group. To the best of our knowledge, this is the first comprehensive report of the Eid1-KO transcriptome of mice brain. Our analysis and experimental data provide a foundation for further studies on understanding function of Eid1 in the brain.


Assuntos
Encéfalo/citologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Animais , Encéfalo/embriologia , Encéfalo/fisiologia , Proliferação de Células/genética , Feminino , Perfilação da Expressão Gênica , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neurais/citologia , Células-Tronco Neurais/fisiologia , Gravidez , Mapas de Interação de Proteínas , Análise de Sequência de RNA
16.
JAMA ; 322(6): 524-534, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31408137

RESUMO

Importance: The effect of intensive blood pressure lowering on brain health remains uncertain. Objective: To evaluate the association of intensive blood pressure treatment with cerebral white matter lesion and brain volumes. Design, Setting, and Participants: A substudy of a multicenter randomized clinical trial of hypertensive adults 50 years or older without a history of diabetes or stroke at 27 sites in the United States. Randomization began on November 8, 2010. The overall trial was stopped early because of benefit for its primary outcome (a composite of cardiovascular events) and all-cause mortality on August 20, 2015. Brain magnetic resonance imaging (MRI) was performed on a subset of participants at baseline (n = 670) and at 4 years of follow-up (n = 449); final follow-up date was July 1, 2016. Interventions: Participants were randomized to a systolic blood pressure (SBP) goal of either less than 120 mm Hg (intensive treatment, n = 355) or less than 140 mm Hg (standard treatment, n = 315). Main Outcomes and Measures: The primary outcome was change in total white matter lesion volume from baseline. Change in total brain volume was a secondary outcome. Results: Among 670 recruited patients who had baseline MRI (mean age, 67.3 [SD, 8.2] years; 40.4% women), 449 (67.0%) completed the follow-up MRI at a median of 3.97 years after randomization, after a median intervention period of 3.40 years. In the intensive treatment group, based on a robust linear mixed model, mean white matter lesion volume increased from 4.57 to 5.49 cm3 (difference, 0.92 cm3 [95% CI, 0.69 to 1.14]) vs an increase from 4.40 to 5.85 cm3 (difference, 1.45 cm3 [95% CI, 1.21 to 1.70]) in the standard treatment group (between-group difference in change, -0.54 cm3 [95% CI, -0.87 to -0.20]). Mean total brain volume decreased from 1134.5 to 1104.0 cm3 (difference, -30.6 cm3 [95% CI, -32.3 to -28.8]) in the intensive treatment group vs a decrease from 1134.0 to 1107.1 cm3 (difference, -26.9 cm3 [95% CI, 24.8 to 28.8]) in the standard treatment group (between-group difference in change, -3.7 cm3 [95% CI, -6.3 to -1.1]). Conclusions and Relevance: Among hypertensive adults, targeting an SBP of less than 120 mm Hg, compared with less than 140 mm Hg, was significantly associated with a smaller increase in cerebral white matter lesion volume and a greater decrease in total brain volume, although the differences were small. Trial Registration: ClinicalTrials.gov Identifier: NCT01206062.


Assuntos
Anti-Hipertensivos/uso terapêutico , Encéfalo/fisiologia , Hipertensão/tratamento farmacológico , Substância Branca/patologia , Idoso , Pressão Sanguínea , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Feminino , Humanos , Hipertensão/complicações , Hipertensão/patologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Fatores de Risco
17.
Nat Neurosci ; 22(9): 1503-1511, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31384015

RESUMO

Everyday decisions frequently require choosing among multiple alternatives. Yet the optimal policy for such decisions is unknown. Here we derive the normative policy for general multi-alternative decisions. This strategy requires evidence accumulation to nonlinear, time-dependent bounds that trigger choices. A geometric symmetry in those boundaries allows the optimal strategy to be implemented by a simple neural circuit involving normalization with fixed decision bounds and an urgency signal. The model captures several key features of the response of decision-making neurons as well as the increase in reaction time as a function of the number of alternatives, known as Hick's law. In addition, we show that in the presence of divisive normalization and internal variability, our model can account for several so-called 'irrational' behaviors, such as the similarity effect as well as the violation of both the independence of irrelevant alternatives principle and the regularity principle.


Assuntos
Encéfalo/fisiologia , Tomada de Decisões/fisiologia , Modelos Neurológicos , Modelos Psicológicos , Animais , Humanos , Recompensa
18.
Nat Biotechnol ; 37(9): 1013-1023, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31406326

RESUMO

Monitoring and modulating the diversity of signals used by neurons and glia in a closed-loop fashion is necessary to establish causative links between biochemical processes within the nervous system and observed behaviors. As developments in neural-interface hardware strive to keep pace with rapid progress in genetically encoded and synthetic reporters and modulators of neural activity, the integration of multiple functional features becomes a key requirement and a pressing challenge in the field of neural engineering. Electrical, optical and chemical approaches have been used to manipulate and record neuronal activity in vivo, with a recent focus on technologies that both integrate multiple modes of interaction with neurons into a single device and enable bidirectional communication with neural circuits with enhanced spatiotemporal precision. These technologies not only are facilitating a greater understanding of the brain, spinal cord and peripheral circuits in the context of health and disease, but also are informing the development of future closed-loop therapies for neurological, neuro-immune and neuroendocrine conditions.


Assuntos
Encéfalo/fisiologia , Técnicas de Diagnóstico Neurológico , Estimulação Elétrica , Rede Nervosa/fisiologia , Humanos , Neurônios/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA