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1.
Ultrason Imaging ; 41(1): 17-34, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239291

RESUMO

We describe the concept of a new imaging modality based on the tracking and dynamic modeling of local intensity changes (ICs) observed in conventional ultrasound images collected during a medium-temperature change. We computed the pixel-by-pixel IC from averaged B-mode images that exhibited different behaviors with varying temperature resulting from changes in the speed of sound, which consequently induce changes in the backscattered energy. Moreover, for each pixel, a first-order polynomial model was adjusted to the different temperature-dependent ICs. The representation of the polynomial angular parameter in 2D pixel space was used to obtain a parametric image. The results obtained by simulations and with real B-mode images indicated that this new ultrasound imaging modality was able to enhance the contrast and highlight structures that were poorly visible or even undetected in conventional images. A temperature change of 3°C was found to be sufficient to generate appropriate images with the proposed method. In addition, if a temperature change of 6°C was considered, the thermal dose, measured as the cumulative number of equivalent minutes at 43°C (CEM43°C), was 2.4 CEM43°C, which is a value that is considered safe according to the literature. We provide a proof-of-concept of a new imaging modality that opens new opportunities for the enhancement of ultrasound images and consequently contributes to improvements in ultrasound-based diagnoses. Our approach is based on images returned by commercial ultrasound scanners. Therefore, it can be implemented in any ultrasound system and is independent of specific ultrasound hardware and software data acquisition characteristics.


Assuntos
Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Temperatura , Ultrassonografia/métodos , Algoritmos , Animais , Simulação por Computador , Estudos de Viabilidade , Modelos Animais , Modelos Estatísticos , Suínos
2.
Biomed Eng Online ; 17(1): 185, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30563526

RESUMO

BACKGROUND: Detection and quantification of cyclic alternating patterns (CAP) components has the potential to serve as a disease bio-marker. Few methods exist to discriminate all the different CAP components, they do not present appropriate sensitivities, and often they are evaluated based on accuracy (AC) that is not an appropriate measure for imbalanced datasets. METHODS: We describe a knowledge discovery methodology in data (KDD) aiming the development of automatic CAP scoring approaches. Automatic CAP scoring was faced from two perspectives: the binary distinction between A-phases and B-phases, and also for multi-class classification of the different CAP components. The most important KDD stages are: extraction of 55 features, feature ranking/transformation, and classification. Classification is performed by (i) support vector machine (SVM), (ii) k-nearest neighbors (k-NN), and (iii) discriminant analysis. We report the weighted accuracy (WAC) that accounts for class imbalance. RESULTS: The study includes 30 subjects from the CAP Sleep Database of Physionet. The best alternative for the discrimination of the different A-phase subtypes involved feature ranking by the minimum redundancy maximum relevance algorithm (mRMR) and classification by SVM, with a WAC of 51%. Concerning the binary discrimination between A-phases and B-phases, k-NN with mRMR ranking achieved the best WAC of 80%. CONCLUSIONS: We describe a KDD that, to the best of our knowledge, was for the first time applied to CAP scoring. In particular, the fully discrimination of the three different A-phases subtypes is a new perspective, since past works tried multi-class approaches but based on grouping of different sub-types. We also considered the weighted accuracy, in addition to simple accuracy, resulting in a more trustworthy performance assessment. Globally, better subtype sensitivities than other published approaches were achieved.


Assuntos
Eletroencefalografia , Reconhecimento Automatizado de Padrão/métodos , Processamento de Sinais Assistido por Computador , Adolescente , Adulto , Idoso , Análise Discriminante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fases do Sono , Máquina de Vetores de Suporte , Adulto Jovem
3.
Biochim Biophys Acta ; 1762(7): 637-46, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16857350

RESUMO

The CLN6 vLINCL is caused by molecular defects in CLN6 gene coding for an ER resident transmembrane protein whose function is unknown. In the present study gene expression profiling of CLN6-deficient fibroblasts using cDNA microarray was undertaken in order to provide novel insights into the molecular mechanisms underlying this neurodegenerative fatal disease. Data were validated by qRT-PCR. Statistically significant alterations of expression were observed for 12 transcripts. The two most overexpressed genes, versican and tissue factor pathway inhibitor 2, are related to extracellular matrix (ECM), predicting changes in ECM-related proteins in CLN6-deficient cells. Transcript profiling also suggested alterations in signal transduction pathways, apoptosis and the immune/inflammatory response. Up-regulated genes related to steroidogenesis or signalling, and the relationship between cholesterol dynamics and glycosphingolipid sorting, led to investigation of free cholesterol and gangliosides in CLN6-deficient fibroblasts. Cholesterol accumulation in lysosomes suggests a homeostasis block as a result of CLN6p deficiency. The cholesterol imbalance may affect structure/function of caveolae and lipid rafts, disrupting signalling transduction pathways and sorting cell mechanisms. Alterations in protein/lipid intracellular trafficking would affect the composition and function of endocytic compartments, including lysosomes. Dysfunctional endosomal/lysosomal vesicles may act as one of the triggers for apoptosis and cell death, and for a secondary protective inflammatory response. In conclusion, the data reported provide novel clues into molecular pathophysiological mechanisms of CLN6-deficiency, and may also help in developing disease biomarkers and therapies for this and other neurodegenerative diseases.


Assuntos
Perfilação da Expressão Gênica , Proteínas de Membrana/genética , Lipofuscinoses Ceroides Neuronais/genética , Células Cultivadas , Colesterol/metabolismo , Proteoglicanas de Sulfatos de Condroitina/genética , Primers do DNA , Fibroblastos/fisiologia , Humanos , Lectinas Tipo C/genética , Lipofuscinoses Ceroides Neuronais/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fenômenos Fisiológicos da Pele , Versicanas
4.
Med Biol Eng Comput ; 44(1-2): 111-6, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16929928

RESUMO

In this paper, a novel black-box modelling scheme applied to non-invasive temperature prediction in a homogeneous medium subjected to therapeutic ultrasound is presented. It is assumed that the temperature in a point of the medium is non-linearly related to some spectral features and one temporal feature, extracted from the collected RF-lines. The black-box models used are radial basis functions neural networks (RBFNNs), where the best-fitted models were selected from the space of model structures using a genetic multi-objective strategy. The best-fitted predictive model presents a maximum absolute error less than 0.4 degrees C in a prediction horizon of approximately 2 h, in an unseen data sequence. This work demonstrates that this type of black-box model is well-suited for punctual and non-invasive temperature estimation, achieving, for a single point estimation, better results than the ones presented in the literature, encouraging research on multi-point non-invasive temperature estimation.


Assuntos
Temperatura Corporal , Redes Neurais de Computação , Terapia por Ultrassom , Humanos , Hipertermia Induzida , Modelos Biológicos
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 5286-5289, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28325021

RESUMO

The global inhomogeneity (GI) index is a electrical impedance tomography (EIT) parameter that quantifies the tidal volume distribution within the lung. In this work the global inhomogeneity index was computed for twenty subjects in order to evaluate his potential use in the detection and follow up of chronic obstructive pulmonary disease (COPD) patients. EIT data of 17 subjects were acquired: 14 patients with the main diagnoses of COPD and 3 healthy subjects which served as a control group. Two or three datasets of around 30 seconds were acquired at 33 scans/s and analysed for each subject. After reconstruction, a tidal EIT image was computed for each breathing cycle and a GI index calculated from it. Results have shown significant differences in GI values between the two groups (0.745 ± 0.007 for COPD and 0.668 ± 0.006 for lung-healthy subject, p <; 0.005). The GI values obtained for each subject have shown small variance between them, which is a good indication of stability. The results suggested that the GI may be useful for the identification and follow up of ventilation problems in patients with COPD.


Assuntos
Impedância Elétrica/uso terapêutico , Pulmão , Doença Pulmonar Obstrutiva Crônica , Volume de Ventilação Pulmonar/fisiologia , Tomografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Masculino , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/fisiopatologia
6.
Hum Gene Ther ; 12(14): 1771-83, 2001 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-11560770

RESUMO

Mutations in the alpha-chain of lysosomal hexosaminidase (EC 3.2.1.52) underlie two distinct biochemical phenotypes known as variant B and variant B1 of G(M2) gangliosidosis. This paper shows that the transduction of human B1-type fibroblasts (producing catalytically inactive alpha-chains) with a retroviral vector encoding the human hexosaminidase alpha-chain leads to a complete correction of HexA (alpha beta dimer) activity with both synthetic and natural substrates. The alpha-subunit overexpression leads to a partial HexB (beta beta dimer) depletion corresponding to about 10% of control HexB activity. The newly synthesized enzyme is correctly processed and targeted to the lysosomes in transduced cells. The high levels of recombinant enzyme correctly produced the metabolic defect, enabling the cells efficiently to degrade the accumulated storage product present in lysosomes. The transduced fibroblasts are also able to secrete HexA efficiently into the culture medium. Moreover, transfer of the human transgene product to B1-type deficient fibroblasts lead to an increase of activity against 4MUGS, the alpha-chain specific synthetic substrate, up to 30% of the control mean activity level. This level of activity might be sufficient to restore the normal ganglioside G(M2) metabolism in recipient cells. The data obtained demonstrate that B1-type phenotype can be efficiently corrected by retrovirus-mediated gene transfer.


Assuntos
DNA Complementar/metabolismo , Fibroblastos/metabolismo , Gangliosídeo G(M2)/genética , Gangliosidoses GM2/genética , Técnicas de Transferência de Genes , Retroviridae/genética , beta-N-Acetil-Hexosaminidases/genética , Células 3T3 , Animais , Linhagem Celular , Dimerização , Eletroforese em Gel de Poliacrilamida , Gangliosídeo G(M2)/metabolismo , Gangliosidoses GM2/metabolismo , Vetores Genéticos , Hexosaminidase A , Hexosaminidase B , Humanos , Imunoglobulina M/metabolismo , Lisossomos/metabolismo , Camundongos , Microscopia de Fluorescência , Mutação , Fenótipo , Testes de Precipitina , Proteínas Recombinantes/metabolismo , Temperatura , Fatores de Tempo , Transdução Genética , Transgenes , beta-N-Acetil-Hexosaminidases/química
7.
Arq Neuropsiquiatr ; 58(3B): 916-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11018833

RESUMO

We report on the preliminary clinical and electrophysiological aspects of an in-patient possibly presenting epilepsia partialis continua (Koshevnikov). We discuss the different etiologies and emphasize on the possible idiopathic form in this case.


Assuntos
Epilepsia Parcial Contínua/diagnóstico , Adulto , Epilepsia Parcial Contínua/etiologia , Epilepsia Parcial Contínua/fisiopatologia , Feminino , Humanos
8.
Arq Neuropsiquiatr ; 57(3B): 761-74, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10751910

RESUMO

We report on the clinical characteristics of amyotrophic lateral sclerosis (ALS) in Fortaleza (Northeastern Brazil). For this, we analyzed retrospectively (from 1980 to 1999) 78 cases of ALS from the Service of Neurology of the University Hospital of Fortaleza diagnosed clinically and laboratorially (EMG, muscle biopsy, myelography, blood biochemistry, muscle enzymes and cranio-cervical X-ray). The results showed that they were mostly sporadic ALS (76/78), and they were divided into definite (n = 36), probable (n = 20), possible (n = 15) and suspected (n = 7), according to the level of diagnostic certainty. They were also subdivided into juvenile (n = 17), early-onset adult (n = 18), age-specific (n = 39) and late-onset (n = 4) groups. Clinically, they presented as initials symptoms, principally, asymmetrical (30/78) and symmetrical (24/78) weakness of extremities, besides bulbar signs, fasciculations, and atrophy. Curiously, pain as first symptom occurred in an expressive fashion (17/78). The predominant initial anatomic site, in this series, was the spinal cord, and mainly affecting the arms. As to the symptom accrual from region to region, this occurs more quickly in contiguous areas, and fasciculations are predominant when bulbar region was associated.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Adolescente , Adulto , Idoso , Esclerose Lateral Amiotrófica/classificação , Esclerose Lateral Amiotrófica/fisiopatologia , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
Ultrasonics ; 54(6): 1692-702, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24630851

RESUMO

This paper assesses the potential of the average gray-level (AVGL) from ultrasonographic (B-mode) images to estimate temperature changes in time and space in a non-invasive way. Experiments were conducted involving a homogeneous bovine muscle sample, and temperature variations were induced by an automatic temperature regulated water bath, and by therapeutic ultrasound. B-mode images and temperatures were recorded simultaneously. After data collection, regions of interest (ROIs) were defined, and the average gray-level variation computed. For the selected ROIs, the AVGL-Temperature relation were determined and studied. Based on uniformly distributed image partitions, two-dimensional temperature maps were developed for homogeneous regions. The color-coded temperature estimates were first obtained from an AVGL-Temperature relation extracted from a specific partition (where temperature was independently measured by a thermocouple), and then extended to the other partitions. This procedure aimed to analyze the AVGL sensitivity to changes not only in time but also in space. Linear and quadratic relations were obtained depending on the heating modality. We found that the AVGL-Temperature relation is reproducible over successive heating and cooling cycles. One important result was that the AVGL-Temperature relations extracted from one region might be used to estimate temperature in other regions (errors inferior to 0.5 °C) when therapeutic ultrasound was applied as a heating source. Based on this result, two-dimensional temperature maps were developed when the samples were heated in the water bath and also by therapeutic ultrasound. The maps were obtained based on a linear relation for the water bath heating, and based on a quadratic model for the therapeutic ultrasound heating. The maps for the water bath experiment reproduce an acceptable heating/cooling pattern, and for the therapeutic ultrasound heating experiment, the maps seem to reproduce temperature profiles consistent with the pressure field of the transducer, and in agreement with temperature maps developed by COMSOL®MultiPhysics simulations.


Assuntos
Músculo Esquelético/diagnóstico por imagem , Termometria/métodos , Terapia por Ultrassom/métodos , Animais , Bovinos , Desenho de Equipamento , Estudos de Viabilidade , Temperatura Alta , Processamento de Imagem Assistida por Computador , Reprodutibilidade dos Testes , Termometria/instrumentação , Transdutores , Terapia por Ultrassom/instrumentação , Ultrassonografia , Água
10.
Artigo em Inglês | MEDLINE | ID: mdl-25570247

RESUMO

Crackles are adventitious and explosive respiratory sounds that can be classified as fine or coarse. These sounds are usually associated with cardiopulmonary diseases such as the chronic obstructive pulmonary disease. In this work seven different features were tested with the objective to identify the best subset of features that allows a robust detection of coarse crackles. Some of the features used in this study are new, namely those based on the local entropy, on the Teager energy and on the residual fit of a Generalized Autoregressive Conditional Heteroskedasticity process. The best features as a function of the number of features used in classification were identified having into account the Matthews correlation coefficient. The best individual feature was based on the local entropy. A significant improvement in the performance was obtained by using the feature based on local entropy and the feature based on the wavelet packed stationary transform - no stationary transform. The addition of more features only allows a smaller improvement.


Assuntos
Sons Respiratórios/diagnóstico , Algoritmos , Entropia , Fractais , Humanos , Reconhecimento Automatizado de Padrão , Processamento de Sinais Assistido por Computador
11.
Sci Rep ; 4: 4545, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24686330

RESUMO

Recent evidence suggests that some seizures are preceded by preictal changes that start from minutes to hours before an ictal event. Nevertheless an adequate statistical evaluation in a large database of continuous multiday recordings is still missing. Here, we investigated the existence of preictal changes in long-term intracranial recordings from 53 patients with intractable partial epilepsy (in total 531 days and 558 clinical seizures). We describe a measure of brain excitability based on the slow modulation of high-frequency gamma activities (40-140 Hz) in ensembles of intracranial contacts. In prospective tests, we found that this index identified preictal changes at levels above chance in 13.2% of the patients (7/53), suggesting that results may be significant for the whole group (p < 0.05). These results provide a demonstration that preictal states can be detected prospectively from EEG data. They advance understanding of the network dynamics leading to seizure and may help develop novel seizure prediction algorithms.


Assuntos
Eletroencefalografia , Epilepsias Parciais/diagnóstico , Adolescente , Adulto , Ondas Encefálicas , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
12.
Clin Exp Metastasis ; 28(6): 505-14, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21479680

RESUMO

Although in the past little attention has been paid to the influence of osteosarcoma cells in osteoclast function, recent studies suggest a close relationship between osteosarcoma aggressiveness and osteoclastic activity. The present study addresses the paracrine effects of MG63 cells, a human osteosarcoma-derived cell line, on the differentiation of peripheral blood osteoclast precursor cells (PBMC). PBMC were cultured for 21 days in the presence of conditioned media from MG63 cell cultures (CM) collected at 48 h (CM_MG1), 7 days (CM_MG2) and 14 days (CM_MG3). MG63 cell cultures displayed the expression of ALP and BMP-2 and, also, the osteoclastogenic genes M-CSF and RANKL, although with a low expression of RANKL. PBMC cultures supplemented with CM presented an evident osteoclastogenic behavior, which was dependent on the culture period of the MG63 cells. The inductive effect appeared to be more relevant for the differentiation and activation genes, c-myc and c-src, and lower for genes associated with osteoclast function. In addition, PBMC cultures displayed increased functional parameters, including calcium phosphate resorbing activity. Assessment of the PBMC cultures in the presence of U0126, PDTC, and indomethacin suggested that in addition to MEK and NFkB pathways, other signaling mechanisms, probably not involving RANKL/RANK interaction, might be activated in the presence of conditioned medium from MG63. In conclusion, MG63 cell line appears to induce a significant paracrine-mediated osteoclastogenic response. Understanding the mechanisms underlying the interaction of osteosarcoma cells and osteoclasts may contribute to the development of new potential approaches in the treatment of such bone metabolic diseases.


Assuntos
Leucócitos Mononucleares/metabolismo , Osteoclastos/metabolismo , Osteossarcoma/patologia , Comunicação Parácrina , Ligante RANK/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Transdução de Sinais , Adulto , Sequência de Bases , Meios de Cultivo Condicionados/metabolismo , Humanos , Leucócitos Mononucleares/citologia , Masculino , Osteoclastos/citologia , Osteossarcoma/genética , Osteossarcoma/metabolismo , Ligante RANK/genética , Receptor Ativador de Fator Nuclear kappa-B/genética , Células Tumorais Cultivadas
13.
J Neurosci Methods ; 200(2): 257-71, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21763347

RESUMO

A Matlab®-based software package, EPILAB, was developed for supporting researchers in performing studies on the prediction of epileptic seizures. It provides an intuitive and convenient graphical user interface. Fundamental concepts that are crucial for epileptic seizure prediction studies were implemented. This includes, for example, the development and statistical validation of prediction methodologies in long-term continuous recordings. Seizure prediction is usually based on electroencephalography (EEG) and electrocardiography (ECG) signals. EPILAB is able to process both EEG and ECG data stored in different formats. More than 35 time and frequency domain measures (features) can be extracted based on univariate and multivariate data analysis. These features can be post-processed and used for prediction purposes. The predictions may be conducted based on optimized thresholds or by applying classifications methods such as artificial neural networks, cellular neuronal networks, and support vector machines. EPILAB proved to be an efficient tool for seizure prediction, and aims to be a way to communicate, evaluate, and compare results and data among the seizure prediction community.


Assuntos
Epilepsia/diagnóstico , Processamento de Sinais Assistido por Computador , Software , Máquina de Vetores de Suporte , Eletrocardiografia , Eletroencefalografia/métodos , Humanos , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
14.
Ultrasonics ; 50(1): 32-43, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19695653

RESUMO

OBJECTIVE AND MOTIVATION: This work reports original results on the possibility of non-invasive temperature estimation (NITE) in a multilayered phantom by applying soft-computing methods. The existence of reliable non-invasive temperature estimator models would improve the security and efficacy of thermal therapies. These points would lead to a broader acceptance of this kind of therapies. Several approaches based on medical imaging technologies were proposed, magnetic resonance imaging (MRI) being appointed as the only one to achieve the acceptable temperature resolutions for hyperthermia purposes. However, MRI intrinsic characteristics (e.g., high instrumentation cost) lead us to use backscattered ultrasound (BSU). Among the different BSU features, temporal echo-shifts have received a major attention. These shifts are due to changes of speed-of-sound and expansion of the medium. NOVELTY ASPECTS: The originality of this work involves two aspects: the estimator model itself is original (based on soft-computing methods) and the application to temperature estimation in a three-layer phantom is also not reported in literature. MATERIALS AND METHODS: In this work a three-layer (non-homogeneous) phantom was developed. The two external layers were composed of (in % of weight): 86.5% degassed water, 11% glycerin and 2.5% agar-agar. The intermediate layer was obtained by adding graphite powder in the amount of 2% of the water weight to the above composition. The phantom was developed to have attenuation and speed-of-sound similar to in vivo muscle, according to the literature. BSU signals were collected and cumulative temporal echo-shifts computed. These shifts and the past temperature values were then considered as possible estimators inputs. A soft-computing methodology was applied to look for appropriate multilayered temperature estimators. The methodology involves radial-basis functions neural networks (RBFNN) with structure optimized by the multi-objective genetic algorithm (MOGA). In this work 40 operating conditions were considered, i.e. five 5-mm spaced spatial points and eight therapeutic intensities (I(SATA)): 0.3, 0.5, 0.7, 1.0, 1.3, 1.5, 1.7 and 2.0W/cm(2). Models were trained and selected to estimate temperature at only four intensities, then during the validation phase, the best-fitted models were analyzed in data collected at the eight intensities. This procedure leads to a more realistic evaluation of the generalisation level of the best-obtained structures. RESULTS AND DISCUSSION: At the end of the identification phase, 82 (preferable) estimator models were achieved. The majority of them present an average maximum absolute error (MAE) inferior to 0.5 degrees C. The best-fitted estimator presents a MAE of only 0.4 degrees C for both the 40 operating conditions. This means that the gold-standard maximum error (0.5 degrees C) pointed for hyperthermia was fulfilled independently of the intensity and spatial position considered, showing the improved generalisation capacity of the identified estimator models. As the majority of the preferable estimator models, the best one presents 6 inputs and 11 neurons. In addition to the appropriate error performance, the estimator models present also a reduced computational complexity and then the possibility to be applied in real-time. CONCLUSIONS: A non-invasive temperature estimation model, based on soft-computing technique, was proposed for a three-layered phantom. The best-achieved estimator models presented an appropriate error performance regardless of the spatial point considered (inside or at the interface of the layers) and of the intensity applied. Other methodologies published so far, estimate temperature only in homogeneous media. The main drawback of the proposed methodology is the necessity of a-priory knowledge of the temperature behavior. Data used for training and optimisation should be representative, i.e., they should cover all possible physical situations of the estimation environment.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Modelos Biológicos , Termografia/métodos , Ultrassonografia/métodos , Simulação por Computador , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Artigo em Inglês | MEDLINE | ID: mdl-21097174

RESUMO

The daily life of epilepsy patients is constrained by the possibility of occurrence of seizures. Until now, seizures cannot be predicted with sufficient sensitivity and specificity. Most of the seizure prediction studies have been focused on a small number of patients, and frequently assuming unrealistic hypothesis. This paper adopts the view that for an appropriate development of reliable predictors one should consider long-term recordings and several features and algorithms integrated in one software tool. A computational environment, based on Matlab (®), is presented, aiming to be an innovative tool for seizure prediction. It results from the need of a powerful and flexible tool for long-term EEG/ECG analysis by multiple features and algorithms. After being extracted, features can be subjected to several reduction and selection methods, and then used for prediction. The predictions can be conducted based on optimized thresholds or by applying computational intelligence methods. One important aspect is the integrated evaluation of the seizure prediction characteristic of the developed predictors.


Assuntos
Algoritmos , Convulsões/diagnóstico , Eletrocardiografia , Eletroencefalografia , Humanos
17.
Mol Genet Metab ; 93(1): 66-73, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17959406

RESUMO

The classical form of late infantile neuronal ceroid lipofuscinosis (LINCL) is a childhood hereditary neurodegenerative disease usually fatal in the first decade of life. The underlying gene, CLN2, encodes the lysosomal soluble enzyme tripeptidyl-peptidase 1 (TPP1). In a Portuguese patient with juvenile form of the disease, the histochemical study revealed the presence of curvilinear inclusions typical of LINCL. In vitro TPP1 activity was deficient in patient's cells. CLN2 gene analysis revealed the transition IVS7-10A>G (g.4196A>G) in both alleles. In silico analysis suggested that A-to-G change in the A-rich region of intron 7 could cause aberrant splicing of exon 8 by creating a novel acceptor splice site. However, because the wild-type acceptor of intron 7 is weak and it was not apparently affected, the severity of this mutation could not be established through sequencing data of gDNA. Normal level of spliced CLN2/mRNA was observed in patient's fibroblasts. In the cDNA, the 9-nt retention of intronic sequence (c.886_887ins9) was observed. The mutation is predicted to result in a protein with three extra amino acids between proline 295 and glycine 296. In patient's fibroblasts the level of mutant CLN2p was reduced to about 60% but the migration pattern was similar to the wild-type protein, suggesting that it was correctly targeted to the lysosomes. Taken together, these findings suggest that the first "ag" is selected for splicing and the mutant protein must retain some residual catalytic activity, thus explaining the late onset and the delayed progression of the disease.


Assuntos
Processamento Alternativo/genética , Endopeptidases/genética , Lipofuscinoses Ceroides Neuronais/genética , Fenótipo , Mutação Puntual/fisiologia , Adulto , Aminopeptidases , Sequência de Bases , Análise Mutacional de DNA , Dipeptidil Peptidases e Tripeptidil Peptidases , Endopeptidases/deficiência , Humanos , Íntrons/genética , Masculino , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Lipofuscinoses Ceroides Neuronais/metabolismo , Lipofuscinoses Ceroides Neuronais/patologia , RNA Mensageiro/metabolismo , Serina Proteases , Tripeptidil-Peptidase 1
18.
Rev. bras. plantas med ; 15(3): 332-336, 2013. tab
Artigo em Português | LILACS | ID: lil-684148

RESUMO

O presente trabalho teve como objetivo investigar a composição química e avaliar a atividade inseticida do extrato acetônico das raízes de Piper alatabaccum sobre Hypothenemus hampei. As raízes foram coletadas no campus da Universidade Federal de Rondônia, em Porto Velho-RO. Diluições de 100,0, 50,0, 25,0, 5,0 e 0,5 mg mL-1 foram utilizadas para exposição na superfície contaminada e aplicação tópica. No teste de repelência, utilizou-se as diluições de 25,0 e 100,0 mg mL-1. As avaliações ocorreram durante 48 horas após a exposição ao extrato. O extrato foi eficiente na mortalidade em aplicação tópica e superfície contaminada, não sendo eficiente no efeito de repelência. Estes resultados apontam para o elevado potencial inseticida do extrato de P. alatabaccum no controle de H. hampei. Identificou-se cinco compostos, sendo três amidas, dihydropiplartine piperovatina e piplartina, e duas flavona, 3',4',5,5',7 pentamethoxyflavone e 5,5',7-trimetóxi-3',4'-methylenedioxyflavone.


The purpose of this work was to investigate the chemical composition and to evaluate the insecticidal activity of the acetonic extract of Piper alatabaccum roots on Hypothenemus hampei. Roots of P. alatabaccum were collected at the University of Rondônia in Porto Velho-RO. Dilutions of 100.0, 50.0, 25.0, 5.0 and 0.5 mg mL-1 were used for exposition in the contaminated surface and for topical application. For the repellence test, 25.0 and 100.0 mg mL-1 dilutions were used. The evaluations occurred during 48 hours after exposure to the extract. The extract was efficient in terms of mortality, but no repellence was observed in the bioassays. These results pointed out the high insecticidal potential of the P. alatabaccum extract to control H. hampei. Five compounds, three amids, piperovatine, dihydropiplartine and piplartine, and two flavones, 3',4',5,5',7-pentamethoxyflavone and 5,5',7-trimethoxy-3',4' methylenedioxyflavone were identified.


Assuntos
Pragas da Agricultura , Piper/química , Controle Biológico de Vetores/métodos , Raízes de Plantas/efeitos adversos , Coffea/classificação , Repelentes de Insetos
19.
Braz J Med Biol Res ; 41(10): 932-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19030714

RESUMO

We have tested the hypothesis that restless leg syndrome (RLS) is related to quality of sleep, fatigue and clinical disability in multiple sclerosis (MS). The diagnosis of RLS used the four minimum criteria defined by the International Restless Legs Syndrome Study Group. Fatigue was assessed by the Fatigue Severity Scale (FSS >27), quality of sleep by the Pittsburgh Sleep Quality Index (PSQI >6), excessive daytime sleepiness by the Epworth Sleepiness Scale (ESS >10) and clinical disability by the Expanded Disability Status Scale (EDSS). Forty-four patients (32 women) aged 14 to 64 years (43 +/- 14) with disease from 0.4 to 23 years (6.7 +/- 5.9) were evaluated. Thirty-five were classified as relapsing-remitting, 5 as primary progressive and 4 as secondary progressive. EDSS varied from 0 to 8.0 (3.6 +/- 2.0). RLS was detected in 12 cases (27%). Patients with RLS presented greater disability (P = 0.01), poorer sleep (P = 0.02) and greater levels of fatigue (P = 0.03). Impaired sleep was present in 23 (52%) and excessive daytime sleepiness in 3 cases (6.8%). Fatigue was present in 32 subjects (73%) and was associated with clinical disability (P = 0.000) and sleep quality (P = 0.002). Age, gender, disease duration, MS pattern, excessive daytime sleepiness and the presence of upper motor neuron signs were not associated with the presence of RLS. Fatigue was best explained by clinical disability and poor sleep quality. Awareness of RLS among health care professionals may contribute to improvement in MS management.


Assuntos
Distúrbios do Sono por Sonolência Excessiva/etiologia , Fadiga/etiologia , Esclerose Múltipla/complicações , Síndrome das Pernas Inquietas/complicações , Adolescente , Adulto , Estudos Transversais , Distúrbios do Sono por Sonolência Excessiva/diagnóstico , Fadiga/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome das Pernas Inquietas/diagnóstico , Índice de Gravidade de Doença , Adulto Jovem
20.
Rev. bras. plantas med ; 15(4,supl.1): 757-762, 2013. graf, tab
Artigo em Português | LILACS | ID: lil-700015

RESUMO

O óleo essencial das folhas de Schinus terebinthifolius foi obtido por hidrodestilação e analisado por CG-EM. O rendimento do óleo foi de 0,8%, sendo identificados 37 constituintes químicos. Os componentes principais foram germacreno D (25,0%), (E)-ß-cariofileno (17,5%) e δ -elemeno (10,5%). O óleo essencial foi diluído em acetona nas concentrações de 10-2 a 10-8 e aplicado aos insetos (Hypothenemus hampei) por aplicação tópica e exposição em superfície contaminada. As taxas de mortalidade foram avaliadas após 24 e 48 horas do início do experimento. A aplicação em superfície contaminada resultou em 25% de mortalidade no controle, enquanto nas diluições de 10-2 a 10-8 foram observados 100,0 a 30,0% de mortalidade. Na aplicação tópica, observou-se 27,5% de mortalidade no controle e 97,5 a 77,5% nas diluições de 10-2 a 10-8.


The essential oil from the leaves of Schinus terebinthifolius was obtained by hydrodistillation and was analyzed by GC-MS. The oil yield was 0.8%, and 37 chemical constituents were identified. The main components were germacrene D (25.0%), (E)-ß-cariophyllene (17.5%) and δ-elemene (10.5%). The essential oil was diluted in acetone in concentrations of 10-2 to 10-8 and it was applied to insects (Hypothenemus hampei) by topical application and exposure to contaminated surface. Mortality rates were evaluated after 24 and 48 hours. The contaminated surface application resulted in 25.0% of mortality in control while the dilutions of 10-2 to 10-8 resulted in 100% to 30.0% of mortality respectively. In the topical application, it was observed 27.5% of mortality in control and 97.5 to 77.5% of mortality in dilutions of 10-2 to 10-8


Assuntos
Óleos Voláteis/síntese química , Controle de Pragas , Anacardiaceae/classificação , Café/metabolismo , Inseticidas/administração & dosagem
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