Normal saline. Results from control (white bars) and OVA-sensitized mice (black

Normal saline. Results from control (white bars) and OVA-sensitized mice (black bars) are presented. doi:10.1371/journal.pone.0048493.gMaterials and Methods AnimalsSixty female BALB/c mice (5 weeks old) were purchased from Elevage Janvier (Le Genest-Saint-Isle, France) and acclimatised in environmentally controlled conditions for 1 week prior to study and for the duration of the experiments. All animal use procedures were approved by our local Animal Care Committee. This study complied with the European law and the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health.Image Post-processingFrom each micro-CT examination, 2 parameters were extracted using Myrian software: ?the total lung mean attenuation (TLA) was automatically assessed using a volume-growing algorithm from bi-thresholded voxels (2900 to 2100 HU). ?the peribronchial mean attenuation (PBA) was assessed using a 3D semi-automatic method lasting 6? min and comprising 4 steps (Figure 2). The first step was to perform automatic segmentation of the bronchial lumen using a bi-threshold approach (21024 to 2900 HU). The second step applied an automatic three-dimensional morphologic dilatation tool to the volume of interest (VOI) obtained from the first step. This dilatation included the peribronchial space into the VOI. A 8voxels dilatation level was found to be optimal to achieve the same peribronchial segmentation than with the previously validated manual method [16]. The third step consisted in creating a second segmentation VOI of the bronchial lumen overwriting the first VOI. The final step was to subtract theModels of AZ876 Allergic Asthma and Scheme of the StudyThe challenge protocols were modified from that described previously [16]. Thirty mice were sensitized by two intraperitoneal injections of 100 mg of ovalbumin (OVA) on days 0 and 14 in the absence of aluminium hydroxide. All the mice were anaesthetised using an intraperitoneal injection of both 50 mg/g ketamine (Panpharma, Fougeres, France) and 5 mg/g xylazine (SigmaAldrich, Saint-Quentin-Fallavier, France). They were then chalIn Vivo Micro-CT Assessment of Airway RemodelingFigure 5. Bland-Altman analysis of manual and semi-automatic methods for peribronchial 1081537 attenuation (PBA) measurements. A) Correlation of peribronchial mean attenuation (PBA) between the two methods. Dashed line represents the line of equality. Solid line corresponds to the regression line. B) Means of measurement between the two methods are plotted against their differences. Solid line corresponds to the mean difference. Dashed lines correspond to the mean difference 62 standard deviations. C) Means of measurement between the two methods are plotted against their standard deviations. doi:10.1371/journal.pone.0048493.gprevious VOI (bronchial lumen only) from the initial VOI (bronchial lumen and peribronchial space). The trachea and the mediastinum were also manually subtracted. The resultant VOI displayed a mean attenuation value named PBA, which was recorded for further analysis. Then, normalized PBA was calculated as 16574785 follow: 1-(PBA/TLA). Finally, using the software MIPAV (Medical Image Processing Analysis and Visualization, National Institutes of Health, MedChemExpress MNS Bethesda, MD, USA), we have applied to selected axial images of each group, a mathematical algorithm that calculated for each pixel (with an attenuation value “x”) a new attenuation value “y”, using this formula: y = 12(x/TLA).Bronchoalveolar LavageBronchoalveolar la.Normal saline. Results from control (white bars) and OVA-sensitized mice (black bars) are presented. doi:10.1371/journal.pone.0048493.gMaterials and Methods AnimalsSixty female BALB/c mice (5 weeks old) were purchased from Elevage Janvier (Le Genest-Saint-Isle, France) and acclimatised in environmentally controlled conditions for 1 week prior to study and for the duration of the experiments. All animal use procedures were approved by our local Animal Care Committee. This study complied with the European law and the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health.Image Post-processingFrom each micro-CT examination, 2 parameters were extracted using Myrian software: ?the total lung mean attenuation (TLA) was automatically assessed using a volume-growing algorithm from bi-thresholded voxels (2900 to 2100 HU). ?the peribronchial mean attenuation (PBA) was assessed using a 3D semi-automatic method lasting 6? min and comprising 4 steps (Figure 2). The first step was to perform automatic segmentation of the bronchial lumen using a bi-threshold approach (21024 to 2900 HU). The second step applied an automatic three-dimensional morphologic dilatation tool to the volume of interest (VOI) obtained from the first step. This dilatation included the peribronchial space into the VOI. A 8voxels dilatation level was found to be optimal to achieve the same peribronchial segmentation than with the previously validated manual method [16]. The third step consisted in creating a second segmentation VOI of the bronchial lumen overwriting the first VOI. The final step was to subtract theModels of Allergic Asthma and Scheme of the StudyThe challenge protocols were modified from that described previously [16]. Thirty mice were sensitized by two intraperitoneal injections of 100 mg of ovalbumin (OVA) on days 0 and 14 in the absence of aluminium hydroxide. All the mice were anaesthetised using an intraperitoneal injection of both 50 mg/g ketamine (Panpharma, Fougeres, France) and 5 mg/g xylazine (SigmaAldrich, Saint-Quentin-Fallavier, France). They were then chalIn Vivo Micro-CT Assessment of Airway RemodelingFigure 5. Bland-Altman analysis of manual and semi-automatic methods for peribronchial 1081537 attenuation (PBA) measurements. A) Correlation of peribronchial mean attenuation (PBA) between the two methods. Dashed line represents the line of equality. Solid line corresponds to the regression line. B) Means of measurement between the two methods are plotted against their differences. Solid line corresponds to the mean difference. Dashed lines correspond to the mean difference 62 standard deviations. C) Means of measurement between the two methods are plotted against their standard deviations. doi:10.1371/journal.pone.0048493.gprevious VOI (bronchial lumen only) from the initial VOI (bronchial lumen and peribronchial space). The trachea and the mediastinum were also manually subtracted. The resultant VOI displayed a mean attenuation value named PBA, which was recorded for further analysis. Then, normalized PBA was calculated as 16574785 follow: 1-(PBA/TLA). Finally, using the software MIPAV (Medical Image Processing Analysis and Visualization, National Institutes of Health, Bethesda, MD, USA), we have applied to selected axial images of each group, a mathematical algorithm that calculated for each pixel (with an attenuation value “x”) a new attenuation value “y”, using this formula: y = 12(x/TLA).Bronchoalveolar LavageBronchoalveolar la.