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1.
Mol Biol Cell ; 35(2): ar23, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38088877

RESUMO

Myristoylated, alanine-rich C-kinase substrate (MARCKS) is an F-actin and phospholipid binding protein implicated in numerous cellular activities, including the regulation of morphology in neuronal dendrites and dendritic spines. MARCKS contains a lysine-rich effector domain that mediates its binding to plasma membrane phosphatidylinositol-4,5-biphosphate (PI(4,5)P2) in a manner controlled by PKC and calcium/calmodulin. In neurons, manipulations of MARCKS concentration and membrane targeting strongly affect the numbers, shapes, and F-actin properties of dendritic spines, but the mechanisms remain unclear. Here, we tested the hypothesis that the effects of MARCKS on dendritic spine morphology are due to its capacity to regulate the availability of plasma membrane PI(4,5)P2. We observed that the concentration of free PI(4,5)P2 on the dendritic plasma membrane was inversely proportional to the concentration of MARCKS. Endogenous PI(4,5)P2 levels were increased or decreased, respectively, by acutely overexpressing either phosphatidylinositol-4-phosphate 5-kinase (PIP5K) or inositol polyphosphate 5-phosphatase (5ptase). PIP5K, like MARCKS depletion, induced severe spine shrinkage; 5ptase, like constitutively membrane-bound MARCKS, induced aberrant spine elongation. These phenotypes involved changes in actin properties driven by the F-actin severing protein cofilin. Collectively, these findings support a model in which neuronal activity regulates actin-dependent spine morphology through antagonistic interactions of MARCKS and PI(4,5)P2.


Assuntos
Actinas , Proteínas de Membrana , Actinas/metabolismo , Proteínas de Membrana/metabolismo , Espinhas Dendríticas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína Quinase C/metabolismo , Fosforilação
2.
Nat Commun ; 13(1): 6037, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36229429

RESUMO

During early ischemic brain injury, glutamate receptor hyperactivation mediates neuronal death via osmotic cell swelling. Here we show that ischemia and excess NMDA receptor activation cause actin to rapidly and extensively reorganize within the somatodendritic compartment. Normally, F-actin is concentrated within dendritic spines. However, <5 min after bath-applied NMDA, F-actin depolymerizes within spines and polymerizes into stable filaments within the dendrite shaft and soma. A similar actinification occurs after experimental ischemia in culture, and photothrombotic stroke in mouse. Following transient NMDA incubation, actinification spontaneously reverses. Na+, Cl-, water, and Ca2+ influx, and spine F-actin depolymerization are all necessary, but not individually sufficient, for actinification, but combined they induce activation of the F-actin polymerization factor inverted formin-2 (INF2). Silencing of INF2 renders neurons vulnerable to cell death and INF2 overexpression is protective. Ischemia-induced dendritic actin reorganization is therefore an intrinsic pro-survival response that protects neurons from death induced by cell edema.


Assuntos
Actinas , N-Metilaspartato , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animais , Espinhas Dendríticas/metabolismo , Forminas , Isquemia/metabolismo , Camundongos , N-Metilaspartato/metabolismo , Neurônios/metabolismo , Receptores de Glutamato/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Água/metabolismo
3.
Mol Biol Cell ; 33(7): ar64, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35352947

RESUMO

Neuron navigator 1 (Nav1) is a cytoskeleton-associated protein expressed during brain development that is necessary for proper neuritogenesis, but the underlying mechanisms are poorly understood. Here we show that Nav1 is present in elongating axon tracts during mouse brain embryogenesis. We found that depletion of Nav1 in cultured neurons disrupts growth cone morphology and neurotrophin-stimulated neuritogenesis. In addition to regulating both F-actin and microtubule properties, Nav1 promotes actin-rich membrane ruffles in the growth cone and promotes macropinocytosis at those membrane ruffles, including internalization of the TrkB receptor for the neurotrophin brain-derived neurotropic factor (BDNF). Growth cone macropinocytosis is important for downstream signaling, neurite targeting, and membrane recycling, implicating Nav1 in one or more of these processes. Depletion of Nav1 also induces transient membrane blebbing via disruption of signaling in the Rho GTPase signaling pathway, supporting the novel role of Nav1 in dynamic actin-based membrane regulation at the cell periphery. These data demonstrate that Nav1 works at the interface of microtubules, actin, and plasma membrane to organize the cell periphery and promote uptake of growth and guidance cues to facilitate neural morphogenesis during development.


Assuntos
Actinas , Cones de Crescimento , Actinas/metabolismo , Animais , Células Cultivadas , Proteínas do Citoesqueleto/metabolismo , Cones de Crescimento/metabolismo , Camundongos , Microtúbulos/metabolismo , Fatores de Crescimento Neural/metabolismo , Neurônios/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo
4.
Sensors (Basel) ; 22(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35009860

RESUMO

Brain-computer interfaces (BCI) can detect specific EEG patterns and translate them into control signals for external devices by providing people suffering from severe motor disabilities with an alternative/additional channel to communicate and interact with the outer world. Many EEG-based BCIs rely on the P300 event-related potentials, mainly because they require training times for the user relatively short and provide higher selection speed. This paper proposes a P300-based portable embedded BCI system realized through an embedded hardware platform based on FPGA (field-programmable gate array), ensuring flexibility, reliability, and high-performance features. The system acquires EEG data during user visual stimulation and processes them in a real-time way to correctly detect and recognize the EEG features. The BCI system is designed to allow to user to perform communication and domotic controls.


Assuntos
Interfaces Cérebro-Computador , Encéfalo , Computadores , Eletroencefalografia , Potenciais Evocados P300 , Humanos , Reprodutibilidade dos Testes , Interface Usuário-Computador
5.
Methods Mol Biol ; 2401: 29-38, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34902120

RESUMO

Microarray technology is a high-throughput technique that can simultaneously measure hundreds of thousands of genes' expression levels. Web and cloud computing tools and databases for storage and analysis of microarray data are necessary for biologists to interpret massive data from experiments. This chapter presents the main databases and web and cloud computing tools for microarray data storage and analysis.


Assuntos
Computação em Nuvem , Software , Armazenamento e Recuperação da Informação , Internet , Análise em Microsséries
6.
Sensors (Basel) ; 21(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34770477

RESUMO

Monitoring physical activity in medical and clinical rehabilitation, in sports environments or as a wellness indicator is helpful to measure, analyze and evaluate physiological parameters involving the correct subject's movements. Thanks to integrated circuit (IC) technologies, wearable sensors and portable devices have expanded rapidly in monitoring physical activities in sports and tele-rehabilitation. Therefore, sensors and signal acquisition devices became essential in the tele-rehabilitation path to obtain accurate and reliable information by analyzing the acquired physiological signals. In this context, this paper provides a state-of-the-art review of the recent advances in electroencephalogram (EEG), electrocardiogram (ECG) and electromyogram (EMG) signal monitoring systems and sensors that are relevant to the field of tele-rehabilitation and health monitoring. Mostly, we focused our contribution in EMG signals to highlight its importance in rehabilitation context applications. This review focuses on analyzing the implementation of sensors and biomedical applications both in literature than in commerce. Moreover, a final review discussion about the analyzed solutions is also reported at the end of this paper to highlight the advantages of physiological monitoring systems in rehabilitation and individuate future advancements in this direction. The main contributions of this paper are (i) the presentation of interesting works in the biomedical area, mainly focusing on sensors and systems for physical rehabilitation and health monitoring between 2016 and up-to-date, and (ii) the indication of the main types of commercial sensors currently being used for biomedical applications.


Assuntos
Eletrocardiografia , Esportes , Eletroencefalografia , Eletromiografia , Monitorização Fisiológica
7.
Sensors (Basel) ; 21(21)2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34770548

RESUMO

Adopting telemonitoring services during the pandemic for people affected by chronic disease is fundamental to ensure access to health care services avoiding the risk of COVID-19 infection. Among chronic diseases, Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig's disease, is a progressive neurodegenerative disease of adulthood, caused by the loss of spinal, bulbar and cortical motor neurons, which leads to paralysis of the voluntary muscles and, also, involves respiratory ones. Therefore, remote monitoring and teleconsulting are essential services for ALS patients with limited mobility, as the disease progresses, and for those living far from ALS centres and hospitals. In addition, the COVID 19 pandemic has increased the need to remotely provide the best care to patients, avoiding infection during ALS centre visits. The paper illustrates an innovative, secure medical monitoring and teleconsultation mobile cloud-based system for disabled people, such as those with ALS (Amyotrophic Lateral Sclerosis). The design aims to remotely monitor biosignals, such as ECG (electrocardiographic) and EMG (electromyographic) signals of ALS patients in order to prevent complications related to the pathology.


Assuntos
Esclerose Lateral Amiotrófica , COVID-19 , Doenças Neurodegenerativas , Adulto , Esclerose Lateral Amiotrófica/diagnóstico , Computação em Nuvem , Humanos , SARS-CoV-2
8.
Sensors (Basel) ; 21(18)2021 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-34577493

RESUMO

The pandemic emergency of the coronavirus disease 2019 (COVID-19) shed light on the need for innovative aids, devices, and assistive technologies to enable people with severe disabilities to live their daily lives. EEG-based Brain-Computer Interfaces (BCIs) can lead individuals with significant health challenges to improve their independence, facilitate participation in activities, thus enhancing overall well-being and preventing impairments. This systematic review provides state-of-the-art applications of EEG-based BCIs, particularly those using motor-imagery (MI) data, to wheelchair control and movement. It presents a thorough examination of the different studies conducted since 2010, focusing on the algorithm analysis, features extraction, features selection, and classification techniques used as well as on wheelchair components and performance evaluation. The results provided in this paper could highlight the limitations of current biomedical instrumentations applied to people with severe disabilities and bring focus to innovative research topics.


Assuntos
Interfaces Cérebro-Computador , COVID-19 , Cadeiras de Rodas , Eletroencefalografia , Humanos , Movimento , SARS-CoV-2
9.
Sensors (Basel) ; 20(4)2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32102437

RESUMO

The diagnosis of psychogenic nonepileptic seizures (PNES) by means of electroencephalography (EEG) is not a trivial task during clinical practice for neurologists. No clear PNES electrophysiological biomarker has yet been found, and the only tool available for diagnosis is video EEG monitoring with recording of a typical episode and clinical history of the subject. In this paper, a data-driven machine learning (ML) pipeline for classifying EEG segments (i.e., epochs) of PNES and healthy controls (CNT) is introduced. This software pipeline consists of a semiautomatic signal processing technique and a supervised ML classifier to aid clinical discriminative diagnosis of PNES by means of an EEG time series. In our ML pipeline, statistical features like the mean, standard deviation, kurtosis, and skewness are extracted in a power spectral density (PSD) map split up in five conventional EEG rhythms (delta, theta, alpha, beta, and the whole band, i.e., 1-32 Hz). Then, the feature vector is fed into three different supervised ML algorithms, namely, the support vector machine (SVM), linear discriminant analysis (LDA), and Bayesian network (BN), to perform EEG segment classification tasks for CNT vs. PNES. The performance of the pipeline algorithm was evaluated on a dataset of 20 EEG signals (10 PNES and 10 CNT) that was recorded in eyes-closed resting condition at the Regional Epilepsy Centre, Great Metropolitan Hospital of Reggio Calabria, University of Catanzaro, Italy. The experimental results showed that PNES vs. CNT discrimination tasks performed via the ML algorithm and validated with random split (RS) achieved an average accuracy of 0.97 ± 0.013 (RS-SVM), 0.99 ± 0.02 (RS-LDA), and 0.82 ± 0.109 (RS-BN). Meanwhile, with leave-one-out (LOO) validation, an average accuracy of 0.98 ± 0.0233 (LOO-SVM), 0.98 ± 0.124 (LOO-LDA), and 0.81 ± 0.109 (LOO-BN) was achieved. Our findings showed that BN was outperformed by SVM and LDA. The promising results of the proposed software pipeline suggest that it may be a valuable tool to support existing clinical diagnosis.


Assuntos
Eletroencefalografia/métodos , Aprendizado de Máquina , Convulsões/diagnóstico , Software , Algoritmos , Humanos , Convulsões/fisiopatologia , Máquina de Vetores de Suporte
10.
Biophys J ; 117(10): 1963-1980, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31668749

RESUMO

Dendritic spines are the primary excitatory postsynaptic sites that act as subcompartments of signaling. Ca2+ is often the first and most rapid signal in spines. Downstream of calcium, the cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway plays a critical role in the regulation of spine formation, morphological modifications, and ultimately, learning and memory. Although the dynamics of calcium are reasonably well-studied, calcium-induced cAMP/PKA dynamics, particularly with respect to frequency modulation, are not fully explored. In this study, we present a well-mixed model for the dynamics of calcium-induced cAMP/PKA dynamics in dendritic spines. The model is constrained using experimental observations in the literature. Further, we measured the calcium oscillation frequency in dendritic spines of cultured hippocampal CA1 neurons and used these dynamics as model inputs. Our model predicts that the various steps in this pathway act as frequency modulators for calcium, and the high frequency of calcium input is filtered by adenylyl cyclase 1 and phosphodiesterases in this pathway such that cAMP/PKA only responds to lower frequencies. This prediction has important implications for noise filtering and long-timescale signal transduction in dendritic spines. A companion manuscript presents a three-dimensional spatial model for the same pathway.


Assuntos
Cálcio/metabolismo , Simulação por Computador , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Espinhas Dendríticas/metabolismo , Transdução de Sinais , Adenilil Ciclases/metabolismo , Animais , Sinalização do Cálcio , Calmodulina/metabolismo , Ativação Enzimática , Feminino , Cinética , Masculino , Modelos Biológicos , Modelos Moleculares , Neurônios/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Fosforilação , Ratos Sprague-Dawley
11.
J Vis Exp ; (150)2019 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-31524872

RESUMO

Neurons differentiated in two-dimensional culture from human pluripotent stem-cell-derived neural progenitor cells (NPCs) represent a powerful model system to explore disease mechanisms and carry out high content screening (HCS) to interrogate compound libraries or identify gene mutation phenotypes. However, with human cells the transition from NPC to functional, mature neuron requires several weeks. Synapses typically start to form after 3 weeks of differentiation in monolayer culture, and several neuron-specific proteins, for example the later expressing pan-neuronal marker NeuN, or the layer 5/6 cerebral cortical neuron marker CTIP2, begin to express around 4-5 weeks post-differentiation. This lengthy differentiation time can be incompatible with optimal culture conditions used for small volume, multi-well HCS platforms. Among the many challenges are the need for well-adhered, uniformly distributed cells with minimal cell clustering, and culture procedures that foster long-term viability and functional synapse maturation. One approach is to differentiate neurons in a large volume format, then replate them at a later time point in HCS-compatible multi-wells. Some main challenges when using this replating approach concern reproducibility and cell viability, due to the stressful disruption of the dendritic and axonal network. Here we demonstrate a detailed and reliable procedure for enzymatically resuspending human induced pluripotent stem cell (hiPSC)-derived neurons after their differentiation for 4-8 weeks in a large-volume format, transferring them to 384-well microtiter plates, and culturing them for a further 1-3 weeks with excellent cell survival. This replating of human neurons not only allows the study of synapse assembly and maturation within two weeks from replating, but also enables studies of neurite regeneration and growth cone characteristics. We provide examples of scalable assays for neuritogenesis and synaptogenesis using a 384-well platform.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes Induzidas/citologia , Neuritos/metabolismo , Neurogênese , Sinapses/metabolismo , Sinalização do Cálcio , Linhagem Celular , Sobrevivência Celular , Células Cultivadas , Dendritos/metabolismo , Eletrodos , Humanos , Neurogênese/fisiologia , Células-Tronco Pluripotentes/citologia , Proteólise , Reprodutibilidade dos Testes
12.
Comput Methods Programs Biomed ; 153: 93-104, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29157465

RESUMO

BACKGROUND AND OBJECTIVE: Use of mobile and web-based applications for diet and weight management is currently increasing. However, the impact of known apps on clinical outcomes is not well-characterized so far. Moreover, availability of food recommender systems providing high quality nutritional advices to both healthy and diet-related chronic diseases users is very limited. In addition, the potentiality of nutraceutical properties of typical regional foods for improving app utility has not been exerted to this end. We present DIETOS, a recommender system for the adaptive delivery of nutrition contents to improve the quality of life of both healthy subjects and patients with diet-related chronic diseases. DIETOS provides highly specialized nutritional advices in different health conditions. METHODS: DIETOS was projected to provide users with health profile and individual nutritional recommendation. Health profiling was based on user answers to dynamic real-time medical questionnaires. Furthermore, DIETOS contains catalogs of typical foods from Calabria, a southern Italian region. Several Calabrian foods have been inserted because of their nutraceutical properties widely reported in several quality studies. DIETOS includes some well known methods for user profiling (overlay profiling) and content adaptation (content selection) coming from general purpose adaptive web systems. RESULTS: DIETOS has been validated for usability for both patients and specialists and for assessing the correctness of the profiling and recommendation, by enrolling 20 chronic kidney disease (CKD) patients at the Department of Nephrology and Dialysis, University Hospital, Catanzaro (Italy) and 20 age-matched healthy controls. Recruited subjects were invited to register to DIETOS and answer to medical questions to determine their health status. Based on our results, DIETOS has high specificity and sensitivity, allowing to determine a medical-controlled user's health profile and to perform a fine-grained recommendation that is better adapted to each user health status. The current version of DIETOS, available online at http://www.easyanalysis.it/dietos is not intended to be used by general users, but only for review purpose. CONCLUSIONS: DIETOS is a novel food recommender system for healthy people and individuals affected by diet-related chronic diseases. The proposed system builds a users health profile and, accordingly, provides individualized nutritional recommendations, also with attention to food geographical origin.


Assuntos
Dieta , Aplicativos Móveis , Monitorização Fisiológica , Autocuidado , Doença Crônica , Diabetes Mellitus/dietoterapia , Humanos , Falência Renal Crônica/dietoterapia
13.
Proc Natl Acad Sci U S A ; 114(22): E4462-E4471, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28500272

RESUMO

The molecular pathogenesis of bipolar disorder (BPD) is poorly understood. Using human-induced pluripotent stem cells (hiPSCs) to unravel such mechanisms in polygenic diseases is generally challenging. However, hiPSCs from BPD patients responsive to lithium offered unique opportunities to discern lithium's target and hence gain molecular insight into BPD. By profiling the proteomics of BDP-hiPSC-derived neurons, we found that lithium alters the phosphorylation state of collapsin response mediator protein-2 (CRMP2). Active nonphosphorylated CRMP2, which binds cytoskeleton, is present throughout the neuron; inactive phosphorylated CRMP2, which dissociates from cytoskeleton, exits dendritic spines. CRMP2 elimination yields aberrant dendritogenesis with diminished spine density and lost lithium responsiveness (LiR). The "set-point" for the ratio of pCRMP2:CRMP2 is elevated uniquely in hiPSC-derived neurons from LiR BPD patients, but not with other psychiatric (including lithium-nonresponsive BPD) and neurological disorders. Lithium (and other pathway modulators) lowers pCRMP2, increasing spine area and density. Human BPD brains show similarly elevated ratios and diminished spine densities; lithium therapy normalizes the ratios and spines. Consistent with such "spine-opathies," human LiR BPD neurons with abnormal ratios evince abnormally steep slopes for calcium flux; lithium normalizes both. Behaviorally, transgenic mice that reproduce lithium's postulated site-of-action in dephosphorylating CRMP2 emulate LiR in BPD. These data suggest that the "lithium response pathway" in BPD governs CRMP2's phosphorylation, which regulates cytoskeletal organization, particularly in spines, modulating neural networks. Aberrations in the posttranslational regulation of this developmentally critical molecule may underlie LiR BPD pathogenesis. Instructively, examining the proteomic profile in hiPSCs of a functional agent-even one whose mechanism-of-action is unknown-might reveal otherwise inscrutable intracellular pathogenic pathways.


Assuntos
Transtorno Bipolar , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Lítio/farmacologia , Modelos Biológicos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Animais , Transtorno Bipolar/genética , Transtorno Bipolar/metabolismo , Transtorno Bipolar/fisiopatologia , Química Encefálica , Cálcio/metabolismo , Células Cultivadas , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Proteômica
14.
Methods Mol Biol ; 1375: 25-39, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25863787

RESUMO

High-throughput platforms such as microarray, mass spectrometry, and next-generation sequencing are producing an increasing volume of omics data that needs large data storage and computing power. Cloud computing offers massive scalable computing and storage, data sharing, on-demand anytime and anywhere access to resources and applications, and thus, it may represent the key technology for facing those issues. In fact, in the recent years it has been adopted for the deployment of different bioinformatics solutions and services both in academia and in the industry. Although this, cloud computing presents several issues regarding the security and privacy of data, that are particularly important when analyzing patients data, such as in personalized medicine. This chapter reviews main academic and industrial cloud-based bioinformatics solutions; with a special focus on microarray data analysis solutions and underlines main issues and problems related to the use of such platforms for the storage and analysis of patients data.


Assuntos
Computação em Nuvem , Biologia Computacional/métodos , Análise em Microsséries/métodos , Humanos
15.
Mol Cell Neurosci ; 68: 36-45, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25827095

RESUMO

Neurons express three closely related dynamin genes. Dynamin 1 has long been implicated in the regulation of synaptic vesicle recycling in nerve terminals, and dynamins 2 and 3 were more recently shown also to contribute to synaptic vesicle recycling in specific and distinguishable ways. In cultured hippocampal neurons we found that chronic suppression of spontaneous network activity differentially regulated the targeting of endogenous dynamins 1 and 3 to nerve terminals, while dynamin 2 was unaffected. Specifically, when neural activity was chronically silenced for 1-2weeks by tetrodotoxin (TTX), the clustering of dynamin 1 at nerve terminals was reduced, while the clustering of dynamin 3 significantly increased. Moreover, dynamin 3 clustering was induced within hours by the sustained blockade of AMPA receptors, suggesting that AMPA receptors may function to prevent Dyn3 accumulation within nerve terminals. Clustering of dynamin 3 was induced by an antagonist of the calcium-dependent protein phosphatase calcineurin, but was not dependent upon intact actin filaments. TTX-induced clustering of Dyn3 occurred with a markedly slower time-course than the previously described clustering of synapsin 1. Potassium-induced depolarization rapidly de-clustered dynamin 3 from nerve terminals within minutes. These results, which have implications for homeostatic synapse restructuring, indicate that the three dynamins have evolved different regulatory mechanisms for trafficking to and from nerve terminals in response to changes in neural activity.


Assuntos
Dinamina III/metabolismo , Dinamina I/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Terminações Pré-Sinápticas/metabolismo , Animais , Células Cultivadas , Dinamina I/genética , Dinamina III/genética , Embrião de Mamíferos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Hipocampo/citologia , Imunossupressores/farmacologia , Neurônios/efeitos dos fármacos , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/ultraestrutura , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/genética , Quinoxalinas/farmacologia , Ratos , Ratos Wistar , Bloqueadores dos Canais de Sódio/farmacologia , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Sinapses/ultraestrutura , Sinaptossomos/metabolismo , Tacrolimo/análogos & derivados , Tacrolimo/farmacologia , Tetrodotoxina/farmacologia , Fatores de Tempo
16.
Arch Phys Med Rehabil ; 96(3 Suppl): S46-53, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25721547

RESUMO

OBJECTIVE: To evaluate the feasibility and usability of an assistive technology (AT) prototype designed to be operated with conventional/alternative input channels and a P300-based brain-computer interface (BCI) in order to provide users who have different degrees of muscular impairment resulting from amyotrophic lateral sclerosis (ALS) with communication and environmental control applications. DESIGN: Proof-of-principle study with a convenience sample. SETTING: An apartment-like space designed to be fully accessible by people with motor disabilities for occupational therapy, placed in a neurologic rehabilitation hospital. PARTICIPANTS: End-users with ALS (N=8; 5 men, 3 women; mean age ± SD, 60 ± 12 y) recruited by a clinical team from an ALS center. INTERVENTIONS: Three experimental conditions based on (1) a widely validated P300-based BCI alone; (2) the AT prototype operated by a conventional/alternative input device tailored to the specific end-user's residual motor abilities; and (3) the AT prototype accessed by a P300-based BCI. These 3 conditions were presented to all participants in 3 different sessions. MAIN OUTCOME MEASURES: System usability was evaluated in terms of effectiveness (accuracy), efficiency (written symbol rate, time for correct selection, workload), and end-user satisfaction (overall satisfaction) domains. A comparison of the data collected in the 3 conditions was performed. RESULTS: Effectiveness and end-user satisfaction did not significantly differ among the 3 experimental conditions. Condition III was less efficient than condition II as expressed by the longer time for correct selection. CONCLUSIONS: A BCI can be used as an input channel to access an AT by persons with ALS, with no significant reduction of usability.


Assuntos
Esclerose Lateral Amiotrófica/reabilitação , Interfaces Cérebro-Computador , Pessoas com Deficiência/reabilitação , Tecnologia Assistiva , Idoso , Auxiliares de Comunicação para Pessoas com Deficiência , Eletroencefalografia , Meio Ambiente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Centros de Reabilitação , Interface Usuário-Computador
17.
Neuroreport ; 25(17): 1331-7, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25304495

RESUMO

Increasing evidence suggests that cellular stress may underlie mood disorders such as bipolar disorder and major depression, particularly as lithium and its targets can protect against neuronal cell death. Here we describe N-methyl-D-aspartate (NMDA)-induced filamentous actin reorganization (NIFAR) as a useful in-vitro model for studying acute neurocellular stress and investigating the effects of mood stabilizers. Brief incubation of cultured neurons with NMDA (50 µM, 5 min) induces marked reorganization of F-actin within the somatodendritic domain of a majority of neurons. During NIFAR, F-actin is rapidly depleted from dendritic spines and aberrantly aggregates within the dendrite shaft. The widely used mood stabilizer lithium chloride prevented NIFAR in a time-dependent and dose-dependent manner, consistent with its known efficacy in treating bipolar disorder. Inhibitors of the lithium target glycogen synthase kinase 3 and its upstream activator phosphoinositide-3-kinase also prevented NIFAR. The antidepressant compounds imipramine and fluoxetine also attenuated NIFAR. These findings have potential relevance to neuropsychiatric diseases characterized by excessive glutamate receptor activity and synaptotoxicity. We propose that protection of the dendritic actin cytoskeleton may be a common mechanism shared by various mood stabilizers.


Assuntos
Actinas/metabolismo , Antipsicóticos/farmacologia , Cloreto de Lítio/farmacologia , N-Metilaspartato/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Animais , Antidepressivos/farmacologia , Células Cultivadas , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/fisiologia , Dendritos/efeitos dos fármacos , Dendritos/fisiologia , Relação Dose-Resposta a Droga , Fluoxetina/farmacologia , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Imipramina/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fatores de Tempo
18.
PLoS One ; 9(4): e94787, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24740405

RESUMO

A current model posits that cofilin-dependent actin severing negatively impacts dendritic spine volume. Studies suggested that increased cofilin activity underlies activity-dependent spine shrinkage, and that reduced cofilin activity induces activity-dependent spine growth. We suggest instead that both types of structural plasticity correlate with decreased cofilin activity. However, the mechanism of inhibition determines the outcome for spine morphology. RNAi in rat hippocampal cultures demonstrates that cofilin is essential for normal spine maintenance. Cofilin-F-actin binding and filament barbed-end production decrease during the early phase of activity-dependent spine shrinkage; cofilin concentration also decreases. Inhibition of the cathepsin B/L family of proteases prevents both cofilin loss and spine shrinkage. Conversely, during activity-dependent spine growth, LIM kinase stimulates cofilin phosphorylation, which activates phospholipase D-1 to promote actin polymerization. These results implicate novel molecular mechanisms and prompt a revision of the current model for how cofilin functions in activity-dependent structural plasticity.


Assuntos
Cofilina 1/metabolismo , Espinhas Dendríticas/fisiologia , Regulação para Baixo , Neurônios/fisiologia , Actinas/metabolismo , Animais , Células Cultivadas , Cofilina 1/genética , Espinhas Dendríticas/efeitos dos fármacos , Feminino , Hipocampo/citologia , Imuno-Histoquímica , Quinases Lim/metabolismo , Potenciação de Longa Duração/fisiologia , Depressão Sináptica de Longo Prazo/fisiologia , Microscopia Confocal , N-Metilaspartato/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fosfolipase D/metabolismo , Fosforilação , Ligação Proteica , Interferência de RNA , Ratos , Tacrolimo/farmacologia , Imagem com Lapso de Tempo
19.
Proc Natl Acad Sci U S A ; 106(11): 4507-12, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19240213

RESUMO

Neuregulin-1 (NRG1) and its ErbB2/B4 receptors are encoded by candidate susceptibility genes for schizophrenia, yet the essential functions of NRG1 signaling in the CNS are still unclear. Using CRE/LOX technology, we have inactivated ErbB2/B4-mediated NRG1 signaling specifically in the CNS. In contrast to expectations, cell layers in the cerebral cortex, hippocampus, and cerebellum develop normally in the mutant mice. Instead, loss of ErbB2/B4 impairs dendritic spine maturation and perturbs interactions of postsynaptic scaffold proteins with glutamate receptors. Conversely, increased NRG1 levels promote spine maturation. ErbB2/B4-deficient mice show increased aggression and reduced prepulse inhibition. Treatment with the antipsychotic drug clozapine reverses the behavioral and spine defects. We conclude that ErbB2/B4-mediated NRG1 signaling modulates dendritic spine maturation, and that defects at glutamatergic synapses likely contribute to the behavioral abnormalities in ErbB2/B4-deficient mice.


Assuntos
Córtex Cerebral/citologia , Espinhas Dendríticas/patologia , Proteínas do Tecido Nervoso/fisiologia , Receptor ErbB-2/fisiologia , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antipsicóticos/farmacologia , Sistema Nervoso Central , Clozapina/farmacologia , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/deficiência , Neuregulina-1 , Proteínas Oncogênicas v-erbB/deficiência , Proteínas Oncogênicas v-erbB/fisiologia , Receptores de Glutamato
20.
J Am Med Dir Assoc ; 9(1): 29-35, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18187110

RESUMO

PURPOSE: Urinary incontinence (UI) is common but inadequately assessed and treated in nursing facility (NF) residents. The purpose of this study is two-fold: (1) to determine perceptions about the importance of UI and its management in the NF setting compared with other geriatric syndromes and (2) to compare barriers to UI care as perceived by physicians, geriatric nurse practitioners (GNPs), directors of nursing and other nurses in administrative positions (DONs), and nursing assistants (NAs). METHODS: Computer-based surveys of physicians and DONs and a hard copy survey of NAs at their national meetings; an online survey of GNPs. RESULTS: Responses included 395 physicians (31% response rate), 152 DONs (34%), 118 GNPs (23%), and 277 NAs (60%). Physicians, GNPs, and DONs evaluated and managed UI significantly less often than 5 other geriatric syndromes (behavioral symptoms of dementia, falls, unintended weight loss, pain, and delirium). In contrast, NAs were more likely to be involved in UI care than in care provided for residents with any of the other 5 syndromes. All 4 groups agreed that UI has less effect on clinical outcomes than the other 5 syndromes. However, DONs rated UI first with respect to cost of care; NAs third behind falls and pain; and physicians and GNPs rated UI fourth behind falls, behavioral symptoms, and delirium. With respect to quality of life effects, physicians and GNPs rated UI fifth and fourth respectively and DONs fourth. In contrast, NAs rated UI second only to pain with respect to its effect on quality of life. Perceived barriers differ among the 4 groups with physicians relatively more concerned that drug treatment alone is ineffective (P = .002); GNPs relatively more concerned with lack of effective nondrug interventions (P = .001); and DONs relatively more concerned about sufficient time to assess and manage UI (P = .001). NA respondents rated concern about anticholinergic drug effects lower than did respondents in the other 3 groups (P = .001). CONCLUSION: Physicians, GNPs, and DONs are more likely to be involved in evaluating and managing behavioral symptoms of dementia, pain, falls, delirium, and unintended weight loss than UI in the NF setting. This leaves NAs as first-line managers for a condition that they perceive to have an important impact on quality of life. Perceived barriers to improving UI care differ among the 4 groups suggesting that approaches to overcoming the barriers should be multi-faceted.


Assuntos
Avaliação Geriátrica/estatística & dados numéricos , Enfermagem Geriátrica/métodos , Instituição de Longa Permanência para Idosos , Papel do Profissional de Enfermagem , Casas de Saúde , Papel do Médico , Incontinência Urinária/terapia , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Computadores , Coleta de Dados , Avaliação Geriátrica/métodos , Humanos , Qualidade de Vida , Incontinência Urinária/complicações , Incontinência Urinária/epidemiologia
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