22 research outputs found

    Analysis of posterior circulation diameters depending on age, sex and side by computed tomography angiography

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    Background: Posterior circulation of brain is important because of vital organs’ blood supply provided by them. In this study, we evaluate the relationship of posterior circulation measurements with age, gender and side by using computed tomography angiography (CTA) images.Materials and methods: A total 199 brain CTA examinations were retrospectively analysed for all posterior circulation arteries (vertebral artery, basilar artery, posterior cerebral artery [PCA], superior cerebellar artery [SCA], anterior inferior cerebellar artery, and posterior inferior cerebellar artery [PICA]) to compare the difference based on age, gender and side.Results: There is no correlation between age and the mean diameters of all vessels (p > 0.05). The mean diameter of left vertebral artery was higher than right vertebral artery in all genders (p = 0.004 for males and p < 0.001 for females). The mean diameter of left SCA and PICA were higher than right SCA and PICA in females (p = 0.032 and p = 0.027, respectively). The mean diameters of basilar, left PCA, left SCA, left vertebral, right PCA, right SCA, right PICA and right vertebral artery were higher in males and that differences were statistically significant (p < 0.001, p = 0.002, p = 0.006, p = 0.004, p = 0.001, p = 0.003, p = 0.002, and p = 0.006, respectively).Conclusions: The posterior circulation vessel diameter is not affected by aging. The mean diameters of basilar artery, both PCAs, both SCAs, right PICA, both vertebral arteries were higher in males. The mean diameter of left vertebral artery is higher than that of right vertebral artery in all genders

    Accuracy of an Artificial Intelligence Deep Learning Algorithm Implementing a Recurrent Neural Network With Long Short-term Memory for the Automated Detection of Calcified Plaques From Coronary Computed Tomography Angiography

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    Purpose: The purpose of this study was to evaluate the accuracy of a novel fully automated deep learning (DL) algorithm implementing a recurrent neural network (RNN) with long short-term memory (LSTM) for the detection of coronary artery calcium (CAC) from coronary computed tomography angiography (CCTA) data. Materials and Methods: Under an IRB waiver and in HIPAA compliance, a total of 194 patients who had undergone CCTA were retrospectively included. Two observers independently evaluated the image quality and recorded the presence of CAC in the right (RCA), the combination of left main and left anterior descending (LM-LAD), and left circumflex (LCx) coronary arteries. Noncontrast CACS scans were allowed to be used in cases of uncertainty. Heart and coronary artery centerline detection and labeling were automatically performed. Presence of CAC was assessed by a RNN-LSTM. The algorithm's overall and per-vessel sensitivity, specificity, and diagnostic accuracy were calculated. Results: CAC was absent in 84 and present in 110 patients. As regards CCTA, the median subjective image quality, signal-to-noise ratio, and contrast-to-noise ratio were 3.0, 13.0, and 11.4. A total of 565 vessels were evaluated. On a per-vessel basis, the algorithm achieved a sensitivity, specificity, and diagnostic accuracy of 93.1% (confidence interval [CI], 84.3%-96.7%), 82.76% (CI, 74.6%-89.4%), and 86.7% (CI, 76.8%-87.9%), respectively, for the RCA, 93.1% (CI, 86.4%-97.7%), 95.5% (CI, 88.77%-98.75%), and 94.2% (CI. 90.2%-94.6%), respectively, for the LM-LAD, and 89.9% (CI, 80.2%-95.8%), 90.0% (CI, 83.2%-94.7%), and 89.9% (CI, 85.0%-94.1%), respectively, for the LCx. The overall sensitivity, specificity, and diagnostic accuracy were 92.1% (CI, 92.1%-95.2%), 88.9% (CI. 84.9%-92.1%), and 90.3% (CI, 88.0%-90.0%), respectively. When accounting for image quality, the algorithm achieved a sensitivity, specificity, and diagnostic accuracy of 76.2%, 87.5%, and 82.2%, respectively, for poor-quality data sets and 93.3%, 89.2% and 90.9%, respectively, when data sets rated adequate or higher were combined. Conclusion: The proposed RNN-LSTM demonstrated high diagnostic accuracy for the detection of CAC from CCTA

    Induction of Blood Brain Barrier Tight Junction Protein Alterations by CD8 T Cells

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    Disruption of the blood brain barrier (BBB) is a hallmark feature of immune-mediated neurological disorders as diverse as viral hemorrhagic fevers, cerebral malaria and acute hemorrhagic leukoencephalitis. Although current models hypothesize that immune cells promote vascular permeability in human disease, the role CD8 T cells play in BBB breakdown remains poorly defined. Our laboratory has developed a novel murine model of CD8 T cell mediated central nervous system (CNS) vascular permeability using a variation of the Theiler's virus model of multiple sclerosis. In previous studies, we observed that MHC class II−/− (CD4 T cell deficient), IFN-γR−/−, TNF-α−/−, TNFR1−/−, TNFR2−/−, and TNFR1/TNFR2 double knockout mice as well as those with inhibition of IL-1 and LTβ activity were susceptible to CNS vascular permeability. Therefore, the objective of this study was to determine the extent immune effector proteins utilized by CD8 T cells, perforin and FasL, contributed to CNS vascular permeability. Using techniques such as fluorescent activated cell sorting (FACS), T1 gadolinium-enhanced magnetic resonance imaging (MRI), FITC-albumin leakage assays, microvessel isolation, western blotting and immunofluorescent microscopy, we show that in vivo stimulation of CNS infiltrating antigen-specific CD8 T cells initiates astrocyte activation, alteration of BBB tight junction proteins and increased CNS vascular permeability in a non-apoptotic manner. Using the aforementioned techniques, we found that despite having similar expansion of CD8 T cells in the brain as wildtype and Fas Ligand deficient animals, perforin deficient mice were resistant to tight junction alterations and CNS vascular permeability. To our knowledge, this study is the first to demonstrate that CNS infiltrating antigen-specific CD8 T cells have the capacity to initiate BBB tight junction disruption through a non-apoptotic perforin dependent mechanism and our model is one of few that are useful for studies in this field. These novel findings are highly relevant to the development of therapies designed to control immune mediated CNS vascular permeability

    Subepicardial adipose tissue thickness and its relation with anthropometric and clinical parameters in pubertal obese children

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    Aim: To determine the relation of echocardiographic subepicardial adipose tissue (SAT) thickness with anthropometric and clinical parameters in pubertal obese children. Subjects and methods: A total of 52 obese pubertal subjects (13.1 +/- 1.56 yr, 27 male patients) and 39 age- and gender-matched lean pubertal subjects (13.0 +/- 1.28 yr, 16 male patients) were included in the study. Serum glucose, lipid profile, and insulin levels were measured during the fasting state. Each subject underwent a transthoracic echocardiography and the SAT thickness was measured during end-diastole from the parasternal long-axis views. Results: The obese pubertal subjects had significantly higher SAT, triceps skin fold (TSF) thickness (mm), waist (WC) and mid-arm circumference (MAC) values (cm) compared with lean pubertal subjects group (p0.05). As an optimal cut-off point, a SAT thickness of 5.25 mm determined IR with 92% sensitivity and 62.1% specificity. Conclusions: Our study showed that SAT thickness in obese pubertal children shows a good correlation with age, SDS-BMI, BMI, WC, MAC, TSF, and HOMA-IR. In addition, our results suggest that SAT thickness might be used as a supportive data for risk stratification of metabolic syndrome in obese children. (J. Endocrinol. Invest. 33: 715-719, 2010) (C) 2010, Editrice Kurti

    Lymphocyte subsets, TNF alpha and interleukin-4 levels in treated and untreated subacute sclerosing panencephalitis patients

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    WOS: 000229647400023PubMed ID: 15885323Immunologic studies in relation to clinical status might help to understand the pathogenesis of subacute sclerosing panencephalitis (SSPE) and the effect of treatment. We measured lymphocyte subsets and intracellular TNF alpha and interleukin-4 levels in peripheral blood in SSPE patients. Patients had elevated percentages of CD8+ cells compared to age-matched control children. Rapidly progressive course was associated with increased CD4+ cells. Treatment with interferons and inosiplex altered the percentage of CD3+, CD4+ and CD19+ cells. TNF alpha and interleukin-4 levels had no correlation with course or treatment. The proportions of lymphocyte subsets appear to have a role in the evolution or manifestations of SSPE, if not in the pathogenesis. (C) 2005 Elsevier B.V. All rights reserved

    Lymphocyte subsets, TNF? and interleukin-4 levels in treated and untreated subacute sclerosing panencephalitis patients

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    PubMedID: 15885323Immunologic studies in relation to clinical status might help to understand the pathogenesis of subacute sclerosing panencephalitis (SSPE) and the effect of treatment. We measured lymphocyte subsets and intracellular TNF? and interleukin-4 levels in peripheral blood in SSPE patients. Patients had elevated percentages of CD8+ cells compared to age-matched control children. Rapidly progressive course was associated with increased CD4+ cells. Treatment with interferons and inosiplex altered the percentage of CD3+, CD4+ and CD19+ cells. TNF? and interleukin-4 levels had no correlation with course or treatment. The proportions of lymphocyte subsets appear to have a role in the evolution or manifestations of SSPE, if not in the pathogenesis. © 2005 Elsevier B.V. All rights reserved.This study was supported by the research grant HEK 01/52 from Hacettepe University, Turkey. Banu Anlar did scientific consultancy for Newport Pharmaceuticals, Ireland
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