Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Neurosci ; : 1-12, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35758006

RESUMO

Aim of the study: To examine the effect of controlled-cortical impact (CCI), a preclinical model of traumatic brain injury (TBI), on intestinal integrity using a binary classification model of machine learning (ML).Materials and methods: Adult, male C57BL/6 mice were subjected to CCI surgery using a stereotaxic impactor (Impact One™). The rotarod and hot-plate tests were performed to assess the neurological deficits.Results: Mice underwent CCI displayed a remarkable neurological deficit as noticed by decreased latency to fall and lesser paw withdrawal latency in rotarod and hot plate test, respectively. Animals were sacrificed 3 days post-injury (dpi). The colon sections were stained with hematoxylin and eosin (H&E) to integrate with machinery tool-based algorithms. Several stained colon images were captured to build a dataset for ML model to predict the impact of CCI vs sham procedure. The best results were obtained with VGG16 features with SVM RBF kernel and VGG16 features with stacked fully connected layers on top. We achieved a test accuracy of 84% and predicted the disrupted gut permeability and epithelium wall of colon in CCI group as compared to sham-operated mice.Conclusion: We suggest that ML may become an important tool in the development of preclinical TBI model and discovery of newer therapeutics.

2.
J Ultrasound Med ; 37(12): 2873-2879, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29663469

RESUMO

OBJECTIVES: To determine whether a novel, noninvasive quantitative ultrasound (US) technique can detect differences in proximal and distal cervical tissue echogenicity in women with and without a shortened cervical length (CL). METHODS: We conducted a retrospective case-control study of singleton pregnancies at 16 to 26 weeks' gestation in which a transvaginal US examination was performed to measure CL from 2013 to 2015. Initial CLs in cases and controls were less than 2.5 cm and 2.5 cm or greater, respectively. For each US image, a region of interest was selected in the proximal and distal cervical stroma, in both the anterior and posterior cervical lips. The Floyd-Steinberg dithering algorithm transformed grayscale pixels in each region of interest into a binary map. A histogram tabulated the number of black and white pixels, allowing determination of the percent echogenicity. The difference in the percent echogenicity was calculated by subtracting the distal cervical echogenicity (average of anterior and posterior lips) from the proximal cervical echogenicity (average of anterior and posterior lips). RESULTS: Ultrasound images from 177 women were analyzed. There was a difference in the percent echogenicity (P < .0001) when comparing women with a short cervix (mean ± SD, 9.8 ± 10.1; n = 102) to women with a normal CL (17.2 ± 9.5; n = 75). Differences were attributable to changes in proximal (P < .008) rather than distal cervical echogenicity. Regardless of CL, the proximal cervix was more echogenic than the distal cervix. CONCLUSIONS: A quantitative US analysis of cervical tissue can detect differences in echogenicity between the proximal and distal cervix in the second trimester. Proximal cervical echogenicity is lower with CL of less than 2.5 cm compared to a normal CL.


Assuntos
Medida do Comprimento Cervical/métodos , Colo do Útero/diagnóstico por imagem , Nascimento Prematuro/diagnóstico por imagem , Ultrassonografia Pré-Natal/métodos , Adulto , Estudos de Casos e Controles , Estudos de Avaliação como Assunto , Feminino , Humanos , Gravidez , Estudos Retrospectivos
3.
J Ultrasound Med ; 36(7): 1437-1443, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28339127

RESUMO

OBJECTIVES: To differentiate preterm (<37 weeks' gestation) from term (≥37 weeks' gestation) fetal lungs by using quantitative texture analysis of ultrasound images. METHODS: This study retrospectively evaluated singleton gestations with valid dating at 20 weeks' gestational age (GA) or later between January 2015 and December 2015. Images were obtained from Voluson E8 ultrasound systems (GE Healthcare, Milwaukee, WI). A region of interest was selected in each fetal lung image at the level of the 4 heart chambers from an area that appeared most representative of the overall lung tissue and had the least shadow. Ultrasonic tissue heterogeneity (heterogeneity index) based on dynamic range calculation was determined for all lung images. This quantification was performed with a custom-made software program that used a dithering technique based on the Floyd-Steinberg algorithm, in which the pixels are transformed into a binary map. Regression analysis was used to determine the correlation and functional association between the heterogeneity index and GA. A receiver operating characteristic curve was used to identify the optimal heterogeneity index cutoff point for differentiating preterm from term fetal lungs. RESULTS: A total of 425 fetal lung ultrasound images (313 preterm and 112 term) were analyzed. Quantitative texture analysis predicted GA with sensitivity and specificity of 87.9% and 92.0%, respectively, based on the optimal receiver operating characteristic cutoff point. CONCLUSIONS: Quantitative ultrasound texture analysis of fetal lung tissue can differentiate preterm fetal lungs from term fetal lungs. Our data suggest that decreased fetal lung heterogeneity on ultrasound imaging is associated with preterm fetuses.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Recém-Nascido Prematuro , Pulmão/diagnóstico por imagem , Pulmão/embriologia , Ultrassonografia Pré-Natal/métodos , Diagnóstico Diferencial , Feminino , Maturidade dos Órgãos Fetais , Humanos , Aumento da Imagem/métodos , Masculino , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
4.
J Urol ; 197(3 Pt 2): 925-930, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27992745

RESUMO

PURPOSE: Gross testicular heterogeneity on ultrasound has been associated with testis loss following testicular torsion in children. We aimed to quantify the extent of temporal heterogeneity associated with testis loss in testicular torsion cases using a noninvasive technique to determine a HI (heterogeneity index) on ultrasound images. MATERIALS AND METHODS: We retrospectively studied the records of patients who presented with acute scrotal pain to the Pediatric Emergency Department over a 6-year period. Ultrasound images of the affected testis and the unaffected contralateral testis were examined using a proprietary program to determine the extent of heterogeneity of each image. The difference between the HI of the torsed testis and that of the contralateral normal testis was termed ΔHI. Receiver operating characteristics curve analysis was performed to determine the ΔHI threshold for nonviability. RESULTS: Among 529 patients who presented with acute scrotal pain 147 had testicular torsion based on surgical findings. Of these 147 patients 110 (74.8%) were found to have a viable testis while 37 (25.2%) had a nonviable testis. Using the ΔHI cutoff of 0.394 or greater for nonviability, sensitivity and specificity were 100% and 94.5%, respectively. Positive and negative predictive values were 86% and 100%, respectively. CONCLUSIONS: Our results demonstrate that a quantifiable temporal gradation of heterogeneity exists and the heterogeneity index can be used as an objective parameter to determine the viability of a torsed testicle. By developing the technology to measure the heterogeneity index in real time, we could potentially identify which patients with testicular torsion have a nonviable testicle and, thus, would not require immediate surgical exploration.


Assuntos
Torção do Cordão Espermático/diagnóstico por imagem , Testículo/diagnóstico por imagem , Sobrevivência de Tecidos , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Torção do Cordão Espermático/complicações , Ultrassonografia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...