k-Nearest Neighbor Curves in Imaging Data Classification

Background: Lung disease quantification via medical image analysis is classically difficult. We propose a method based on normalized nearest neighborhood distance classifications for comparing individual CT scan air-trapping distributions (representing 3D segmented parenchyma). Previously, between-image comparisons were precluded by the variation inherent to parenchyma segmentations, the dimensions of which are patient- and image-specific by nature.Method: Nearest neighbor distance estimations are normalized by a theoretical distance according to the uniform distribution of air trapping. This normalization renders images (of different sizes, shapes, and/or densities) comparable. The estimated distances for the k-nearest neighbor describe the proximity of point patterns over the image. Our approach assumes and requires a defined homogeneous space; therefore, a completion pretreatment is applied beforehand.Results: Model robustness is characterized via simulation in order to verify that the required initial transformations do not bias uniformly sampled results. Additional simulations were performed to assess the discriminant power of the method for different point pattern profiles. Simulation results demonstrate that the method robustly recognizes pattern dissimilarity. Finally, the model is applied on real data for illustrative purposes.Conclusion: We demonstrate that a parenchyma-cuboid completion method provides the means of characterizing air-trapping patterns in a chosen segmentation and, importantly, comparing such patterns between patients and images

MORTALITE ET MORBIDITE CHEZ LE GRAND PREMATURE (RESULTATS DE LA REGION NORD PAS DE CALAIS A PARTIR D'UNE ETUDE PROSPECTIVE, EN POPULATION REALISEE DURANT L'ANNEE 1997 : EPIPAGE)

LILLE2-BU Santé-Recherche (593502101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

k-Nearest Neighbor Curves in Imaging Data Classification

International audienc

Streamlining basophil activation testing to enable assay miniaturization and automation of sample preparation

Background: Numerous studies have demonstrated the capabilities of the basophil activation test (BAT) but various parameters such as a lack of standardization and a time consuming and labor intensive workflow continue to hinder the field to fully leverage the capabilities of this technique. When pediatric patients have to be considered, an additional limitation is related to blood volume consumption. Objectives: This work aimed at developing and characterizing a simplified and standardized whole-blood based BAT prototype procedure and at further assessing the feasibility of automating and miniaturizing the developed assay into a 96 well plate format. Methods: A dry and room temperature stable reagent technology was used to simplify and standardize BAT. Under optimized conditions, EDTA anticoagulated whole blood samples of non-allergic and allergic donors ( < 24 h old) together with calcium containing buffer were added to ready-to-use dry reagent tubes or 96 well plates (negative controls, positive controls and allergen tests) containing a 5 color compensation-free antibody panel (CD45-KrO/CD3-PC7/CRTH2-A647/CD203c-PE/CD63-PB). Upon mixing and incubation at 37 degrees C for 15 min, erythrocytes were lysed and samples were analyzed by flow cytometry without further washing steps. While it is important to precisely control the incubation time to minimize the assay variability, herein, a 15 min incubation time was chosen as it provides a suitable compromise for both the magnitude of basophil activation and the quality of the staining. A Biomek NXP robotic platform (Beckman Coulter) was used for automation and both CD203c and CD63 levels were monitored to characterize basophil reactivity. Results: This streamlined BAT protocol is no-wash, compensation free and only requires 4 pipetting steps to be completed. The assessment of assay performance characteristics showed wide applicability, satisfactory repeatability and a high degree of standardization as demonstrated by very low infra-assay and inter-operator variabilities (CVs < 10%). Leveraging these technical foundations, it was then proven that this new BAT procedure can easily be transposed into the 96 well plate format, thereby benefiting from a miniaturized format and full automation capabilities. When considering 8 dilution points to characterize the ex vivo basophil reactivity of a given whole blood sample, we found that as little as 51.1.L of blood per point could be used. Conclusions: A whole blood based and simplified procedure for BAT is proposed. It relies on a dry antibody formulation technology and requires only a few manual steps to be completed. This procedure can also be transposed in a 96 well plate format, fully automated and miniaturized, when sample volume reduction, throughput increase or unattended sample preparation is required

Bronchial Epithelial Calcium Metabolism Impairment in Smokers and Chronic Obstructive Pulmonary Disease Decreased ORAI3 Signaling

The airway epithelium represents a fragile environmental interface potentially disturbed by cigarette smoke, the major risk factor for developing Chronic Obstructive Pulmonary Disease (COPD). Cigarette smoke leads to bronchial epithelial damage on ciliated, goblet and club cells, which could involve calcium signaling. Calcium is a key messenger involved in virtually all fundamental physiological functions, including mucus and cytokine secretion, cilia beating and epithelial repair. In this study, we analyzed calcium signaling in Air-Liquid Interface reconstituted bronchial epithelium from control subjects and smokers (with and without COPD). We further aimed to determine how smoking impaired calcium signaling. Firstly, we showed that the endoplasmic reticulum (ER) depletion of calcium stores was decreased in COPD patients and that the calcium influx was decreased in epithelial cells from smokers (regardless of COPD status). In addition, acute cigarette smoke exposition lead to a decrease in ER calcium release, significant in smoker subjects, and to a decrease in calcium influx only in control subjects. Furthermore, the differential expression of 55 genes involved in calcium signaling highlighted that only ORAI3 expression was significantly altered in smokers (regardless of COPD status). Finally, we incubated epithelial cells with an ORAI antagonist (GSK-7975A). GSK-7975A altered calcium influx and ciliary beating but not mucus and cytokine secretion or epithelial repair in control subjects. Our data suggest that calcium signaling is impaired in smoker epithelia (regardless of COPD status) and involves ORAI3. Moreover, ORAI3 is additionally involved in ciliary beating

Reply to: Altered Calcium in Ciliary Dysfunction: Potential Role of ER Stress and Ciliophagy

International audienc

Redox-switching of ternary Ni(ii) and Cu(ii) complexes synthesis, experimental and theoretical studies along with second-order nonlinear optical properties

International audienceFour new ternary Ni(ii) and Cu(ii) complexes of ONO tridentate Schiff base and pyridylmethylenepyran (PyMP) ligands [(R-ONO)M(PyMP)] (R = anisyl = An M = Ni 1, Cu 2; R = ferrocenyl = Fc M = Ni 3, Cu 4) have been synthesized under facile reaction conditions starting from R-ONOH2, metal(ii) nitrate salts, and PyMP; R-ONOH2 stands for the Schiff base ligand precursors obtained by condensation of either 1-anisyl- or 1-ferrocenyl-butan-1,3-dione and 2-aminophenol. They have been thoroughly characterized with the help of various physicochemical tools, such as CHN analyses, IR and UV-vis spectra, H-1 NMR for diamagnetic Ni(ii) derivatives 1 and 3, and HRMS for paramagnetic Cu(ii) species 2 and 4. The molecular structures of 1-3 were authenticated by single-crystal X-ray diffraction methods, along with that of the doubly phenoxide-bridged dimer [Cu-2(mu-ONO-Fc)(2)(PyMp)(2)] (4 '), resulting from the recrystallization of 4. In 1-3, the four-coordinate nickel and copper atoms adopt a square planar geometry, whereas in 4 ' the Cu-II metal ion is five-coordinated in a square pyramidal environment with the pyridyl nitrogen occupying the apex. Electrochemical studies reveal two well-separated redox waves. The spin density distribution analyses reveal that the initial oxidation process is associated with a ligand-based level, with some ferrocenyl participation for the heterobimetallic compounds 3 and 4. Reversible redox switching can be established for 1 and 3 by time-resolved spectroelectrochemistry under thin-layer conditions where electrochemical cycling is associated with a significant modification of the UV-vis spectra of the chromophores. The second-order nonlinear optical responses of 1-4 along with those of assumed bispyrylium dimeric species 5 and 6, generated by chemical oxidation of 1 and 3, respectively, have been determined by harmonic light scattering measurements in dichloromethane solutions at 1.91 mu m incident wavelength. Rather high beta values ranging from 270-530 x 10(-30) esu were determined for 1-4. The beta value of 5 (800 x 10(-30) esu) was found to be almost twice that of its monomeric precursor 1, whereas the beta value of 6 (160 x 10(-30) esu) is reduced by half with respect to that of 3. In 5 the anisyl retains its donor ability whereas in 6 the electron-donating character of the oxidized ferrocenyl moiety is cancelled. Optimized geometries of the four compounds 1-4 as well as their electronic structures and that of their respective cations 1(+)-4(+) have been analyzed through DFT calculations, while TD-DFT computation has been used to interpret the major features of the UV-vis spectra