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1.
Comput Biol Med ; 134: 104489, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34015672

RESUMO

Chronic dermatological ulcers cause great discomfort to patients, and while monitoring the size of wounds over time provides significant clues about the healing evolution and the clinical condition of patients, the lack of practical applications in existing studies impairs users' access to appropriate treatment and diagnosis methods. We propose the UTrack framework to help with the acquisition of photos, the segmentation and measurement of wounds, the storage of photos and symptoms, and the visualization of the evolution of ulcer healing. UTrack-App is a mobile app for the framework, which processes images taken by standard mobile device cameras without specialized equipment and stores all data locally. The user manually delineates the regions of the wound and the measurement object, and the tool uses the proposed UTrack-Seg segmentation method to segment them. UTrack-App also allows users to manually input a unit of measurement (centimeter or inch) in the image to improve the wound area estimation. Experiments show that UTrack-Seg outperforms its state-of-the-art competitors in ulcer segmentation tasks, improving F-Measure by up to 82.5% when compared to superpixel-based approaches and up to 19% when compared to Deep Learning ones. The method is unsupervised, and it semi-automatically segments real-world images with 0.9 of F-Measure, on average. The automatic measurement outperformed the manual process in three out of five different rulers. UTrack-App takes at most 30 s to perform all evaluation steps over high-resolution images, thus being well-suited to analyze ulcers using standard mobile devices.


Assuntos
Aplicativos Móveis , Telemedicina , Atenção à Saúde , Humanos , Úlcera , Cicatrização
2.
Comput Methods Programs Biomed ; 191: 105376, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32066047

RESUMO

BACKGROUND AND OBJECTIVES: Bedridden patients presenting chronic skin ulcers often need to be examined at home. Healthcare professionals follow the evolution of the patients' condition by regularly taking pictures of the wounds, as different aspects of the wound can indicate the healing stages of the ulcer, including depth, location, and size. The manual measurement of the wounds' size is often inaccurate, time-consuming, and can also cause discomfort to the patient. In this work, we propose the Automatic Skin Ulcer Region Assessment ASURA framework to accurately segment the wound and automatically measure its size. METHODS: ASURA uses an encoder/decoder deep neural network to perform the segmentation, which detects the measurement ruler/tape present in the image and estimates its pixel density. RESULTS: Experimental results show that ASURA outperforms the state-of-the-art methods by up to 16% regarding the Dice score, being able to correctly segment the wound with a Dice score higher than 90%. ASURA automatically estimates the pixel density of the images with a relative error of 5%. When using a semi-automatic approach, ASURA was able to estimate the area of the wound in square centimeters with a relative error of 14%. CONCLUSIONS: The results show that ASURA is well-suited for the problem of segmenting and automatically measuring skin ulcers.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Úlcera Cutânea/diagnóstico por imagem , Úlcera Cutânea/fisiopatologia , Humanos
3.
Comput Methods Programs Biomed ; 183: 105079, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31542688

RESUMO

BACKGROUND: The image-based identification of distinct tissues within dermatological wounds enhances patients' care since it requires no intrusive evaluations. This manuscript presents an approach, we named QTDU, that combines deep learning models with superpixel-driven segmentation methods for assessing the quality of tissues from dermatological ulcers. METHOD: QTDU consists of a three-stage pipeline for the obtaining of ulcer segmentation, tissues' labeling, and wounded area quantification. We set up our approach by using a real and annotated set of dermatological ulcers for training several deep learning models to the identification of ulcered superpixels. RESULTS: Empirical evaluations on 179,572 superpixels divided into four classes showed QTDU accurately spot wounded tissues (AUC = 0.986, sensitivity = 0.97, and specificity = 0.974) and outperformed machine-learning approaches in up to 8.2% regarding F1-Score through fine-tuning of a ResNet-based model. Last, but not least, experimental evaluations also showed QTDU correctly quantified wounded tissue areas within a 0.089 Mean Absolute Error ratio. CONCLUSIONS: Results indicate QTDU effectiveness for both tissue segmentation and wounded area quantification tasks. When compared to existing machine-learning approaches, the combination of superpixels and deep learning models outperformed the competitors within strong significant levels.


Assuntos
Aprendizado Profundo , Dermatologia/métodos , Diagnóstico por Computador/métodos , Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Úlcera Cutânea/diagnóstico por imagem , Algoritmos , Área Sob a Curva , Teorema de Bayes , Humanos , Aprendizado de Máquina , Análise de Componente Principal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Máquina de Vetores de Suporte
4.
Arq Bras Endocrinol Metabol ; 54(4): 375-80, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20625649

RESUMO

UNLABELLED: INTRODUSTION: Sibutramine has been described as a drug recommended for treatment of obesity, since it has the ability to inhibit the reuptake of serotonin and noradrenaline in the central nervous system, thereby increasing energy expenditure. OBJECTIVE: Investigate the anxiogenic and anxiolytic effects of acute and chronic treatment with sibutramine in rats submitted to the task of the elevated plus-maze. METHODS: Diazepam was used as a positive control for the anxiolytic effect, and the task of the elevated plus-maze showed sensitivity to detect the effect. In the chronic treatment, sibutramine was ingested for a period of two months. RESULTS: The acute and chronic treatments at the studied dose, which is described to produce a maximum effect of anti-obesity in rats, did not interfere with anxiety. CONCLUSIONS: The acute and chronic administration of sibutramine is not related to anxiolytic or anxiogenic effects.


Assuntos
Ansiolíticos/farmacologia , Fármacos Antiobesidade/farmacologia , Ansiedade/tratamento farmacológico , Ciclobutanos/farmacologia , Análise de Variância , Animais , Ansiolíticos/efeitos adversos , Fármacos Antiobesidade/efeitos adversos , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Wistar
5.
J Org Chem ; 71(1): 244-50, 2006 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-16388643

RESUMO

[reaction: see text] Palladium(0)-catalyzed cross-coupling between potassium aryltrifluoroborate salts and aryl tellurides proceeds readily to afford the desired biaryls in good to excellent yield. The reaction seems to be unaffected by the presence of electron-withdrawing or electron-donating substituents in both the potassium aryltrifluoroborate salts and aryl tellurides partners. Biaryls containing a variety of functional groups can be prepared. A chemoselectivity study was also carried out using aryl tellurides bearing halogen atoms in the same compound. In addition, this new version of the Suzuki-Miyaura cross-coupling reaction was monitored by electrospray ionization mass spectrometry where some reaction intermediates were detected and analyzed.


Assuntos
Boratos/química , Potássio/química , Sais/química , Telúrio/química , Catálise , Dimerização , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
6.
Arq. bras. endocrinol. metab ; 54(4): 375-380, jun. 2010. ilus, graf
Artigo em Inglês | LILACS | ID: lil-550707

RESUMO

INTRODUSTION: Sibutramine has been described as a drug recommended for treatment of obesity, since it has the ability to inhibit the reuptake of serotonin and noradrenaline in the central nervous system, thereby increasing energy expenditure. OBJECTIVE: Investigate the anxiogenic and anxiolytic effects of acute and chronic treatment with sibutramine in rats submitted to the task of the elevated plus-maze. METHODS: Diazepam was used as a positive control for the anxiolytic effect, and the task of the elevated plus-maze showed sensitivity to detect the effect. In the chronic treatment, sibutramine was ingested for a period of two months. RESULTS: The acute and chronic treatments at the studied dose, which is described to produce a maximum effect of anti-obesity in rats, did not interfere with anxiety. CONCLUSIONS: The acute and chronic administration of sibutramine is not related to anxiolytic or anxiogenic effects.


INTRODUÇÃO: A sibutramina tem sido descrita como um fármaco recomendado para o tratamento da obesidade, uma vez que tem a capacidade de inibir a recaptação de serotonina e noradrenalina no sistema nervoso central, aumentando assim o gasto energético. OBJETIVO: Investigar os efeitos ansiogênico e ansiolítico dos tratamentos agudo e crônico com a sibutramina em ratos Wistar submetidos à tarefa do labirinto em cruz elevado. MÉTODOS: O diazepam foi usado como controle positivo para o efeito ansiolítico, e a tarefa do labirinto em cruz elevado apresentou sensibilidade para detectar o efeito. No tratamento crônico, a sibutramina foi ingerida por um período de dois meses. RESULTADOS: Os tratamentos agudo e crônico, na dose estudada, que é descrita para produzir um efeito de antiobesidade máxima em ratos, não interferem na ansiedade. CONCLUSÕES: As administrações aguda e crônica de sibutramina não estão relacionadas aos efeitos ansiolítico ou ansiogênico.


Assuntos
Animais , Masculino , Ratos , Ansiolíticos/farmacologia , Fármacos Antiobesidade/farmacologia , Ansiedade/tratamento farmacológico , Ciclobutanos/farmacologia , Análise de Variância , Ansiolíticos/efeitos adversos , Fármacos Antiobesidade/efeitos adversos , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Aprendizagem em Labirinto/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Distribuição Aleatória , Ratos Wistar
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