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1.
Eur Neurol ; 74(3-4): 202-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26588015

RESUMO

Alzheimer's disease (AD) is a progressive disorder affecting intellectual, behavioral and functional abilities. It is associated with age and pathological alterations leading to the formation of amyloid plaques and tangles. It is the most common source of dementia in the older population, which varies in its degrees of severity. We are yet to find efficient methods of diagnosis of AD, as its symptoms vary among individuals. This paper presents a review of recent research on the clinical neurophysiological and automated electroencephalography-based diagnosis of the AD. Various therapeutic measures are also discussed briefly.


Assuntos
Doença de Alzheimer/diagnóstico , Eletroencefalografia/métodos , Idoso de 80 Anos ou mais , Doença de Alzheimer/terapia , Humanos , Masculino
2.
Eur Neurol ; 74(5-6): 268-87, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26650683

RESUMO

BACKGROUND: The brain's continuous neural activity during sleep can be monitored by electroencephalogram (EEG) signals. The EEG wave pattern and frequency vary during five stages of sleep. These subtle variations in sleep EEG signals cannot be easily detected through visual inspection. SUMMARY: A range of time, frequency, time-frequency and nonlinear analysis methods can be applied to understand the complex physiological signals and their chaotic behavior. This paper presents a comprehensive comparative review and analysis of 29 nonlinear dynamics measures for EEG-based sleep stage detection. KEY MESSAGES: The characteristic ranges of these features are reported for the five different sleep stages. All nonlinear measures produce clinically significant results, that is, they can discriminate the individual sleep stages. Feature ranking based on the statistical F-value, however, shows that the third order cumulant of higher order spectra yields the most discriminative result. The distinct value ranges for each sleep stage and the discriminative power of the features can be used for sleep disorder diagnosis, treatment monitoring, and drug efficacy assessment.


Assuntos
Eletroencefalografia/estatística & dados numéricos , Polissonografia/estatística & dados numéricos , Processamento de Sinais Assistido por Computador , Fases do Sono/fisiologia , Encéfalo/fisiologia , Gráficos por Computador , Eletroencefalografia/métodos , Humanos , Dinâmica não Linear
3.
Rev Neurosci ; 25(6): 841-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25222596

RESUMO

Autism spectrum disorder (ASD) is a complex neurobiological disorder characterized by neuropsychological and behavioral deficits. Cognitive impairment, lack of social skills, and stereotyped behavior are the major autistic symptoms, visible after a certain age. It is one of the fastest growing disabilities. Its current prevalence rate in the U.S. estimated by the Centers for Disease Control and Prevention is 1 in 68 births. The genetic and physiological structure of the brain is studied to determine the pathology of autism, but diagnosis of autism at an early age is challenging due to the existing phenotypic and etiological heterogeneity among ASD individuals. Volumetric and neuroimaging techniques are explored to elucidate the neuroanatomy of the ASD brain. Nuroanatomical, neurochemical, and neuroimaging biomarkers can help in the early diagnosis and treatment of ASD. This paper presents a review of the types of autism, etiologies, early detection, and treatment of ASD.


Assuntos
Agenesia do Corpo Caloso , Transtorno Autístico , Transtornos Globais do Desenvolvimento Infantil , Cognição/fisiologia , Deficiências do Desenvolvimento , Agenesia do Corpo Caloso/diagnóstico , Agenesia do Corpo Caloso/etiologia , Agenesia do Corpo Caloso/terapia , Transtorno Autístico/diagnóstico , Transtorno Autístico/etiologia , Transtorno Autístico/terapia , Criança , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Transtornos Globais do Desenvolvimento Infantil/etiologia , Transtornos Globais do Desenvolvimento Infantil/terapia , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/etiologia , Deficiências do Desenvolvimento/terapia , Diagnóstico Precoce , Humanos
4.
Rev Neurosci ; 25(6): 851-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25153585

RESUMO

Autism is a type of neurodevelopmental disorder affecting the memory, behavior, emotion, learning ability, and communication of an individual. An early detection of the abnormality, due to irregular processing in the brain, can be achieved using electroencephalograms (EEG). The variations in the EEG signals cannot be deciphered by mere visual inspection. Computer-aided diagnostic tools can be used to recognize the subtle and invisible information present in the irregular EEG pattern and diagnose autism. This paper presents a state-of-the-art review of automated EEG-based diagnosis of autism. Various time domain, frequency domain, time-frequency domain, and nonlinear dynamics for the analysis of autistic EEG signals are described briefly. A focus of the review is the use of nonlinear dynamics and chaos theory to discover the mathematical biomarkers for the diagnosis of the autism analogous to biological markers. A combination of the time-frequency and nonlinear dynamic analysis is the most effective approach to characterize the nonstationary and chaotic physiological signals for the automated EEG-based diagnosis of autism spectrum disorder (ASD). The features extracted using these nonlinear methods can be used as mathematical markers to detect the early stage of autism and aid the clinicians in their diagnosis. This will expedite the administration of appropriate therapies to treat the disorder.


Assuntos
Transtorno Autístico/diagnóstico , Transtorno Autístico/fisiopatologia , Eletroencefalografia/métodos , Modelos Neurológicos , Dinâmica não Linear , Análise de Ondaletas , Humanos
5.
Epilepsy Behav ; 41: 257-63, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25461226

RESUMO

Alcoholism is a severe disorder that affects the functionality of neurons in the central nervous system (CNS) and alters the behavior of the affected person. Electroencephalogram (EEG) signals can be used as a diagnostic tool in the evaluation of subjects with alcoholism. The neurophysiological interpretation of EEG signals in persons with alcoholism (PWA) is based on observation and interpretation of the frequency and power in their EEGs compared to EEG signals from persons without alcoholism. This paper presents a review of the known features of EEGs obtained from PWA and proposes that the impact of alcoholism on the brain can be determined by computer-aided analysis of EEGs through extracting the minute variations in the EEG signals that can differentiate the EEGs of PWA from those of nonaffected persons. The authors advance the idea of automated computer-aided diagnosis (CAD) of alcoholism by employing the EEG signals. This is achieved through judicious combination of signal processing techniques such as wavelet, nonlinear dynamics, and chaos theory and pattern recognition and classification techniques. A CAD system is cost-effective and efficient and can be used as a decision support system by physicians in the diagnosis and treatment of alcoholism especially those who do not specialize in alcoholism or neurophysiology. It can also be of great value to rehabilitation centers to assess PWA over time and to monitor the impact of treatment aimed at minimizing or reversing the effects of the disease on the brain. A CAD system can be used to determine the extent of alcoholism-related changes in EEG signals (low, medium, high) and the effectiveness of therapeutic plans.


Assuntos
Alcoolismo/diagnóstico , Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Humanos
6.
Mol Biotechnol ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004678

RESUMO

Alzheimer's disease (AD) poses a significant global health challenge, necessitating the exploration of novel therapeutic strategies. Fyn Tyrosine Kinase has emerged as a key player in AD pathogenesis, making it an attractive target for drug development. This study focuses on investigating the potential of Papaveroline as a drug candidate for AD by targeting Fyn Tyrosine Kinase. The research employed high-throughput virtual screening and QSAR analysis were conducted to identify compounds with optimal drug-like properties, emphasizing adherence to ADMET parameters for further evaluation. Molecular dynamics simulations to analyze the binding interactions between Papaveroline and Staurosporine with Fyn Tyrosine Kinase over a 200-ns period. The study revealed detailed insights into the binding mechanisms and stability of the Papaveroline-Fyn complex, showcasing the compound's potential as an inhibitor of Fyn Tyrosine Kinase. Comparative analysis with natural compounds and a reference compound highlighted Papaveroline's unique characteristics and promising therapeutic implications for AD treatment. Overall, the findings underscore Papaveroline's potential as a valuable drug candidate for targeting Fyn Tyrosine Kinase in AD therapy, offering new avenues for drug discovery in neurodegenerative diseases. This study contributes to advancing our understanding of molecular interactions in AD pathogenesis and paves the way for further research and development in this critical area.

7.
Indian J Otolaryngol Head Neck Surg ; 76(2): 1516-1521, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566695

RESUMO

Since the COVID-19 pandemic, masks have become far more widely used by doctors and are now commonplace in the hospital, with many professionals still wearing them for extended amounts of time. Emerging literature describing numerous mask-related difficulties prompted the authors to conduct a study aimed at assessing the self-perceived impact on voices of teaching doctors due to facial protective gear. In this study carried out from October 2021 to March 2022, data was gathered from 170 pre-, para-, and clinical professionals who were involved in offline teaching. Over half of teaching medical professionals were found to be vocally fatigued. Pre and para-clinical professionals have greater vocal tiredness and avoidance than clinical doctors (p = 0.016). The type of mask used does not make a significant difference in degree of vocal fatigue. Individuals with lingering respiratory difficulties following COVID-19 were significantly more vocally fatigued than their recovered peers (p value for tiredness and avoidance = 0.010). Thus, teaching doctors are at risk of impaired quality of life due to vocal fatigue. Further research on vocal habits and rest practices in the study population may help identify the most effective interventions. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-023-04350-8.

8.
Comput Biol Med ; 102: 234-241, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30253869

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease of the central nervous system caused due to the loss of dopaminergic neurons. It is classified under movement disorder as patients with PD present with tremor, rigidity, postural changes, and a decrease in spontaneous movements. Comorbidities including anxiety, depression, fatigue, and sleep disorders are observed prior to the diagnosis of PD. Gene mutations, exposure to toxic substances, and aging are considered as the causative factors of PD even though its genesis is unknown. This paper reviews PD etiologies, progression, and in particular measurable indicators of PD such as neuroimaging and electrophysiology modalities. In addition to gene therapy, neuroprotective, pharmacological, and neural transplantation treatments, researchers are actively aiming at identifying biological markers of PD with the goal of early diagnosis. Neuroimaging modalities used together with advanced machine learning techniques offer a promising path for the early detection and intervention in PD patients.


Assuntos
Doença de Parkinson/diagnóstico , Doença de Parkinson/etiologia , Doença de Parkinson/terapia , Encéfalo/diagnóstico por imagem , Comorbidade , Aprendizado Profundo , Progressão da Doença , Neurônios Dopaminérgicos/fisiologia , Diagnóstico Precoce , Fenômenos Eletrofisiológicos , Humanos , Aprendizado de Máquina , Transtornos dos Movimentos/fisiopatologia , Mutação , Neuroimagem , Transtornos do Sono-Vigília/fisiopatologia
9.
Comput Biol Med ; 88: 93-99, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28709145

RESUMO

Attention Deficit Hyperactivity Disorder (ADHD) is the most common childhood psychiatric disorder that may continue through adolescence and adulthood. Hyperactivity, inattention and impulsivity are the key behavioral features observed in children with ADHD. ADHD is normally diagnosed only when a child continues to have symptoms of hyperactivity, impulsivity and inattention at a greater degree than the normal for six months or more. In recent years there has been significant research to diagnose ADHD in a quantitative way using medical imaging and signal processing techniques. This paper presents a review of recent research on diagnosis of ADHD using medical imaging and signal processing techniques. This research is especially valuable for early diagnosis of ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Encéfalo , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/genética , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Criança , Pré-Escolar , Eletroencefalografia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Magnetoencefalografia , Masculino , Processamento de Sinais Assistido por Computador
10.
Comput Biol Med ; 88: 72-83, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28700902

RESUMO

Glaucoma is an optic neuropathy defined by characteristic damage to the optic nerve and accompanying visual field deficits. Early diagnosis and treatment are critical to prevent irreversible vision loss and ultimate blindness. Current techniques for computer-aided analysis of the optic nerve and retinal nerve fiber layer (RNFL) are expensive and require keen interpretation by trained specialists. Hence, an automated system is highly desirable for a cost-effective and accurate screening for the diagnosis of glaucoma. This paper presents a new methodology and a computerized diagnostic system. Adaptive histogram equalization is used to convert color images to grayscale images followed by convolution of these images with Leung-Malik (LM), Schmid (S), and maximum response (MR4 and MR8) filter banks. The basic microstructures in typical images are called textons. The convolution process produces textons. Local configuration pattern (LCP) features are extracted from these textons. The significant features are selected using a sequential floating forward search (SFFS) method and ranked using the statistical t-test. Finally, various classifiers are used for classification of images into normal and glaucomatous classes. A high classification accuracy of 95.8% is achieved using six features obtained from the LM filter bank and the k-nearest neighbor (kNN) classifier. A glaucoma integrative index (GRI) is also formulated to obtain a reliable and effective system.


Assuntos
Algoritmos , Glaucoma/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Técnicas de Diagnóstico Oftalmológico , Humanos
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