Search results for "feature"
showing 10 items of 4091 documents
Quantification of the heterogeneity of prognostic cellular biomarkers in ewing sarcoma using automated image and random survival forest analysis
2014
Driven by genomic somatic variation, tumour tissues are typically heterogeneous, yet unbiased quantitative methods are rarely used to analyse heterogeneity at the protein level. Motivated by this problem, we developed automated image segmentation of images of multiple biomarkers in Ewing sarcoma to generate distributions of biomarkers between and within tumour cells. We further integrate high dimensional data with patient clinical outcomes utilising random survival forest (RSF) machine learning. Using material from cohorts of genetically diagnosed Ewing sarcoma with EWSR1 chromosomal translocations, confocal images of tissue microarrays were segmented with level sets and watershed algorithm…
Cerebral White Matter Lesions and Dysmorphisms: Signs Suggestive of 6p25 Deletion Syndrome—Literature Review
2019
AbstractDeletion of the region including chromosome 6p25 has been defined as a syndrome, with more than 68 reported cases. Individuals affected by the syndrome exhibit variable findings, including developmental delay and intellectual disability, cardiac anomalies, dysmorphic features, and—less commonly—skeletal and renal malformations. Ocular and hearing abnormalities are the most notable presenting features. The region encompasses more than 15 genes, of which the FOX group is the most likely causal factor of the clinical manifestations. We report the case of a 2-year-old child with developmental delay, generalized hypotonia, facial dysmorphism, and anomalies involving malformations of the …
Primary glioblastomas with and without EGFR amplification: Relationship to genetic alterations and clinicopathological features
2009
Glioblastomas express a notable heterogeneity in both the histological and cell patterns with glial astrocytic differentiation. Primary glioblastoma, which is the most frequent presentation (90-95%), occurs mainly in older patients and arises de novo, without any clinical or histological evidence of a less malignant precursor lesion. EGFR amplification has been identified as a genetic hallmark of primary glioblastomas and occurs in 40-60% of cases. However, there exist primary glioblastomas without EGFR amplification/overexpression. The purpose of this study was to stabilize the association between cases with and without EGFR gene amplification with clinical and genetic parameters in 45 cas…
Nodular morphea keloidal type: A rare case with paradigmatic histopathology significantly accompanied by a flawless surgical scar
2020
Nodular morphea is a rare variant of localized scleroderma, clinically and histopathologically characterized by cutaneous nodules or plaques associated or superimposed to the flat lesions of classic morphea. Accordingly, the association of such outgrowths with systemic sclerosis is designated as nodular scleroderma. Sometimes these lesions appear as firm, erythematous and irregularly curvy plaques resembling keloids or hypertrophic scars, thus characterizing keloidal morphea or keloidal scleroderma. These mystifying features can make the diagnosis challenging, especially in the absence of a well‐documented medical history. Here we report a case of keloidal morphea with multiple histopatholo…
Identifying the primary site of origin of MRI brain metastases from lung and breast cancer following a 2D radiomics approach
2017
Detection of brain metastases in patients with undiagnosed primary cancer is unusual but still an existing phenomenon. In these cases, identifying the cancer site of origin is non-feasible by visual examination of magnetic resonance (MR) images. Recently, radiomics has been proposed to analyze differences among classes of visually imperceptible imaging characteristics. In this study we analyzed 46 T1-weighted MR images of brain metastases from 29 patients: 29 of lung and 17 of breast origin. A total of 43 radiomics texture features were extracted from the metastatic lesions. Support vector machine (SVM) and k-nearest neighbors (k-NN) classifiers were implemented to evaluate the classificati…
A review of oral biopsies in children and adolescents: a clinicopathological study of a case series
2013
Objective: The aim of this study was to evaluate the clinicopathological features of oral lesions in children and adolescents diagnosed in an Oral Pathology Laboratory. Study design: Between 2000 and 2010, all oral lesions diagnosed in patients younger than 18 years old, from the Oral Pathology Laboratory, Federal University of Pernambuco, Brazil, were selected for the study. The clinical data were obtained from the patient charts filed in the Laboratory. All cases were microscopically reviewed and the diagnosis classified into 10 categories. Results: From the 2395 lesions, 315 (13.1%) occurred in this age group. The lesions were more common in the female gender (59%) during the second deca…
Vollautomatische Detektion und Quantifizierung des Lungenemphysems in Dünnschicht-MD-CT des Thorax durch eine neue, speziell entwickelte Software
2004
Purpose: Introduction of a novel software tool (YACTA - yet another CT analyzer) for detection and quantification of pulmonary emphysema in thin-slice chest MDCT data sets. Materials and Methods: Consisting of grey-level threshold-based algorithms (e. g., region-growing), expert rules and morphological image postprocessing YACTA segments the tracheobronchial tree prior to the detection and quantification of pulmonary emphysema. In addition to general parameters, such as the mean lung density (MLD) and the emphysema index (EI - also described as pixel index PI), the previously described bullae index (BI) is transformed into a three-dimensional parameter for a morphological description of emp…
Support vector machine classification of brain metastasis and radiation necrosis based on texture analysis in MRI
2015
Purpose To develop a classification model using texture features and support vector machine in contrast-enhanced T1-weighted images to differentiate between brain metastasis and radiation necrosis. Methods Texture features were extracted from 115 lesions: 32 of them previously diagnosed as radiation necrosis, 23 as radiation-treated metastasis and 60 untreated metastases; including a total of 179 features derived from six texture analysis methods. A feature selection technique based on support vector machine was used to obtain a subset of features that provide optimal performance. Results The highest classification accuracy evaluated over test sets was achieved with a subset of ten features…
Effect of catchment characteristics on aquatic carbon export from a boreal catchment and its importance in regional carbon cycling
2013
Inland waters transport and emit into the atmosphere large amounts of carbon (C), which originates from terrestrial ecosystems. The effect of land cover and land-use practises on C export from terrestrial ecosystems to inland waters is not fully understood, especially in heterogeneous landscapes under human influence. We sampled for dissolved C species in five tributaries with well-determined subcatchments (total size 174.5 km(2)), as well as in various points of two of the subcatchments draining to a boreal lake in southern Finland over a full year. Our aim was to find out how land cover and land-use affect C export from the catchments, as well as CH4 and CO2 concentrations of the streams,…
Historical mining and smelting in the Vosges Mountains (France) recorded in two ombrotrophic peat bogs
2010
Two peat sequences were sampled in the vicinity of the main mining districts of the Vosges Mountains: Sainte-Marie-aux-Mines and Plancher-les-Mines. Lead isotopic compositions and excess lead fluxes were calculated for each of these radiocarbon-dated sequences. Geochemical records are in very good agreement with the mining history of the area, well known over the last millennium. Except for an anomaly corresponding to the Middle Bronze Age which has not yet been resolved, there is no clear geochemical evidence of local metal production in the Vosges before the 10th century as excess lead deposition archived between 500 BC and 500 AD is attributed to long-range transport of polluted particul…