The preprocessing step of most computer-aided diagnosis (CAD) systems for identifying the lung diseases is lung segmentation. We present a novel lung segmentation technique based on watershed ...transform, which is fast and accurate. Lung region is precisely marked with internal and external markers. The markers are combined with the gradient image of the original data and watershed transform is applied on the combined data to find the lung borders. Rolling ball filter is used to smooth the contour and fill the cavities while preserving the original borders. The proposed method eliminates the tasks of finding an optimal threshold and separating the attached left and right lungs, which are two common practices in most lung segmentation methods and require a significant amount of time. We have applied our new approach on several pulmonary CT images and the results reveal the speed, robustness and accuracy of this method.
Background: Due to multiple drug resistance against antimicrobial drugs for treatment of infectious disease, investigations to discovering new antibacterial compounds from natural sources have been ...designated. Objective: According to antimicrobial effects of some Capparis species, this study was carried out to evaluate the antimicrobial activity of the extract and fractions of Capparis cartilaginea and Capparis mucronifolia against 6 bacterial strains. Methods: Aerial parts of the Capparis species were extracted by maceration method using methanol and fractionated separately by liquid-liquid fractionation method. The antibacterial activity of the extract and fractions were studied against 6 bacterial strains using MIC microplate method. Total flavonoid content (TFC) of the extracts and fractions was determined using AlCl3 reagent. Results: The total extract and methanolic fractions of C. mucronifolia were the most effective fractions against the bacterial strains. Methanolic fraction of C. cartilaginea was the most effective fraction with MIC 10.42 µg/ml against Salmonella enterica. The highest antibacterial activity of C.mucronifolia was against Staphylococcus epidermidis with MIC 7.8 µg/ml. Methanolic fractions of Capparis species showed the highest TFC value in AlCl3 colorimetric assay. Conclusion: The results of this study indicate that the extracts and fractions of Capparis cartilaginea and Capparis mucronifolia have antimicrobial effect against 6 gram positive and gram negative strains. According to the high amount of flavonoids in methanolic fraction of C. mucronifolia, the antibacterial activity may be related to the flavonoid compounds of this plant.
Since several lung diseases are diagnosed based on the patterns of lung tissue in medical images, texture segmentation is an essential part of the most computer aided diagnosis (CAD) systems. In this ...paper a novel composite method is proposed to segment the abnormality in lung tissue in pediatric CT images. The proposed approach is based on wavelet transform and intensity similarities. Our focus is on the honeycomb texture in lung tissue. After segmenting lung regions, wavelet transform is applied to decompose the image. The vertical subimage of lung is thresholded to extract high resolution areas. Then the regions with low pixel intensities are kept and grown to segment the honeycomb regions. The proposed method has been tested on 91 pediatric chest CT images containing healthy and unhealthy lung images. Statistical analysis shows the sensitivity of 100% along with the specificity of 94.44%.
Contrast-enhanced digital breast tomosynthesis (CE DBT) has been proposed to image the effects of tumour angiogenesis. In this work we evaluate the relationship between CE DBT image signal and ...histopathology in an animal tumour model to provide evidence for the underlying basis for signal enhancement. A VX2 carcinoma was induced in the hind leg of 8 rabbits and grown for up to 3 weeks. Projection images from a 60 s contrast-enhanced CT acquisition were used to reconstruct CE DBT volumes. Fiducial markers implanted in the tumour provided a means for registration between images and stained whole-mount sections. The relationship between CE DBT image signal and angiogenesis marker expression was determined. A correlation was found between CE DBT image signal and dextran extravasation, which strengthened during washout, while no relationship was observed with CD31 staining. These results suggest that for clinical CE DBT, washout phase imaging will provide information on vascular permeability.
Since several lung diseases are diagnosed based on the patterns of lung tissue in medical images, texture segmentation is an essential part of the most computer aided diagnosis (CAD) systems. In this ...paper a novel composite method is proposed to segment the abnormality in lung tissue in pediatric CT images. The proposed approach is based on wavelet transform and intensity similarities. Our focus is on the honeycomb texture in lung tissue. After segmenting lung regions, wavelet transform is applied to decompose the image. The vertical subimage of lung is thresholded to extract high resolution areas. Then the regions with low pixel intensities are kept and grown to segment the honeycomb regions. The proposed method has been tested on 91 pediatric chest CT images containing healthy and unhealthy lung images. Statistical analysis has been done and the results show the sensitivity of 100% along with the specificity of 94.44%.
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