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1.
BMC Med Imaging ; 16: 14, 2016 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-26864653

RESUMEN

BACKGROUND: Lung diseases (resulting from air pollution) require a widely accessible method for risk estimation and early diagnosis to ensure proper and responsive treatment. Radiomics-based fractal dimension analysis of X-ray computed tomography attenuation patterns in chest voxels of mice exposed to different air polluting agents was performed to model early stages of disease and establish differential diagnosis. METHODS: To model different types of air pollution, BALBc/ByJ mouse groups were exposed to cigarette smoke combined with ozone, sulphur dioxide gas and a control group was established. Two weeks after exposure, the frequency distributions of image voxel attenuation data were evaluated. Specific cut-off ranges were defined to group voxels by attenuation. Cut-off ranges were binarized and their spatial pattern was associated with calculated fractal dimension, then abstracted by the fractal dimension -- cut-off range mathematical function. Nonparametric Kruskal-Wallis (KW) and Mann-Whitney post hoc (MWph) tests were used. RESULTS: Each cut-off range versus fractal dimension function plot was found to contain two distinctive Gaussian curves. The ratios of the Gaussian curve parameters are considerably significant and are statistically distinguishable within the three exposure groups. CONCLUSIONS: A new radiomics evaluation method was established based on analysis of the fractal dimension of chest X-ray computed tomography data segments. The specific attenuation patterns calculated utilizing our method may diagnose and monitor certain lung diseases, such as chronic obstructive pulmonary disease (COPD), asthma, tuberculosis or lung carcinomas.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Interpretación de Imagen Asistida por Computador/métodos , Enfermedades Pulmonares/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Animales , Modelos Animales de Enfermedad , Femenino , Fractales , Humanos , Enfermedades Pulmonares/inducido químicamente , Ratones , Ratones Endogámicos BALB C , Distribución Normal
2.
Eur J Pharm Sci ; 95: 46-53, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27687639

RESUMEN

The objective of the study was to reveal the influence of necessarily added barium sulfate (BaSO4) X-ray contrast material on floating drug delivery tablets. Based on literature survey, a chosen floating tablet composition was determined containing HPMC and carbopol 943P as matrix polymers. One-factor factorial design with five levels was created for evaluation of BaSO4 (X1) effects on experimental parameters of tablets including: floating lag time, total floating time, swelling-, erosion-, dissolution-, release kinetics parameters and X-ray detected volume changes of tablets. Applied concentrations of BaSO4 were between 0 and 20.0% resulting in remarkable alteration of experimental parameters related especially to flotation. Drastic deterioration of floating lag time and total floating time could be observed above 15.0% BaSO4. Furthermore, BaSO4 showed to increase the integrity of tablet matrix by reducing eroding properties. A novel evaluation of dissolutions from floating drug delivery systems was introduced, which could assess the quantity of drug dissolved from dosage form in floating state. In the cases of tablets containing 20.0% BaSO4, only the 40% of total API amount could be dissolved in floating state. In vitro fine resolution X-ray CT imagings were performed to study the volume change and the voxel distributions as a function of HU attenuations by histogram analysis of the images. X-ray detected relative volume change results did not show significant difference between samples. After 24h, all tablets containing BaSO4 could be segmented, which highlighted the fact that enough BaSO4 remained in the tablets for their identification.


Asunto(s)
Sulfato de Bario/química , Medios de Contraste/química , Sistemas de Liberación de Medicamentos/métodos , Tomografía Computarizada por Rayos X/métodos , Comprimidos , Rayos X
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