In the past years, cardiovascular progenitor cells have been isolated from the human heart and characterized. Up to date, no studies have been reported in which the developmental potential of foetal and adult cardiovascular progenitors was tested simultaneously. However, intrinsic differences will likely affect interpretations regarding progenitor cell potential and application for regenerative medicine.
View Article and Find Full Text PDFPurpose: The application and large-scale evaluation of minimum cost path approaches for coronary centerline extraction from computed tomography coronary angiography (CTCA) data and the development and evaluation of a novel method to reduce the user-interaction time.
Methods: A semiautomatic method based on a minimum cost path approach is evaluated for two different cost functions. The first cost function is based on a frequently used vesselness measure and intensity information, and the second is a recently proposed cost function based on region statistics.
Objective: To improve regeneration of the injured myocardium, it is necessary to enhance the intrinsic capacity of the heart to regenerate itself and/or replace the damaged tissue by cell transplantation. Cardiomyocyte progenitor cells (CMPCs) are a promising cell population, easily expanded and efficiently differentiated into beating cardiomyocytes. Recently, several studies have demonstrated that microRNAs (miRNAs) are important for stem cell maintenance and differentiation via translational repression.
View Article and Find Full Text PDFPurpose: To provide a broad perspective concerning the recent use of receiver operating characteristic (ROC) analysis in medical imaging by reviewing ROC studies published in Radiology between 1997 and 2006 for experimental design, imaging modality, medical condition, and ROC paradigm.
Materials And Methods: Two hundred ninety-five studies were obtained by conducting a literature search with PubMed with two criteria: publication in Radiology between 1997 and 2006 and occurrence of the phrase "receiver operating characteristic." Studies returned by the query that were not diagnostic imaging procedure performance evaluations were excluded.
Classifier design for a given classification task needs to take into consideration both the complexity of the classifier and the size of the dataset that is available for training the classifier. With limited training data, as often is the situation in computer-aided diagnosis of medical images, a classifier with simple structure (e.g.
View Article and Find Full Text PDFAm J Physiol Cell Physiol
November 2009
The cholinergic anti-inflammatory pathway is a physiological mechanism that inhibits cytokine production and minimizes tissue injury during inflammation. Previous investigations revealed that cholinergic stimulation (via cholinergic agonists and vagus nerve stimulation) suppresses endothelial cell activation and leukocyte recruitment. The purpose of this study was to investigate the mechanisms by which cholinergic agonists (e.
View Article and Find Full Text PDFUnlabelled: Early versions of uncemented femoral total hip stems were often associated with thigh pain thought to be due to micromotion between the implant and bone in the distal uncoated regions. An extensively coated stem was introduced in 1992 to reduce that risk. We therefore asked whether second-generation extensively porous-coated cementless femoral stems in patients younger than 50 years of age would (1) be durable in terms of revisions; (2) provide high functional scores and reduce thigh pain; and (3) show radiographic signs of durability, including a reduction in stress shielding.
View Article and Find Full Text PDFInf Process Med Imaging
September 2009
This paper presents a novel method for segmenting the coronary lumen in CTA data. The method is based on graph cuts, with edge-weights depending on the intensity of the centerline, and robust kernel regression. A quantitative evaluation in 28 coronary arteries from 12 patients is performed by comparing the semi-automatic segmentations to manual annotations.
View Article and Find Full Text PDFObjective: Progesterone supplementation has been shown to be efficacious in preventing preterm birth. We sought to investigate the effects of progesterone on fetal inflammatory responses.
Study Design: Fetal mononuclear cells were isolated from umbilical cord blood and exposed to vehicle or progesterone (P4) for 1 hour prior to lipopolysaccharide (LPS) stimulation.
Efficiently obtaining a reliable coronary artery centerline from computed tomography angiography data is relevant in clinical practice. Whereas numerous methods have been presented for this purpose, up to now no standardized evaluation methodology has been published to reliably evaluate and compare the performance of the existing or newly developed coronary artery centerline extraction algorithms. This paper describes a standardized evaluation methodology and reference database for the quantitative evaluation of coronary artery centerline extraction algorithms.
View Article and Find Full Text PDFThe cholinergic anti-inflammatory pathway is a physiological mechanism that inhibits cytokine production and diminishes tissue injury during inflammation. Recent studies demonstrate that cholinergic signaling reduces adhesion molecule expression and chemokine production by endothelial cells and suppresses leukocyte migration during inflammation. It is unclear how vagus nerve stimulation regulates leukocyte trafficking because the vagus nerve does not innervate endothelial cells.
View Article and Find Full Text PDFCardiomyocyte progenitor cells (CMPCs) can be isolated from the human heart and differentiated into cardiomyocytes in vitro. A comprehensive assessment of their electrical phenotype upon differentiation is essential to predict potential future applications of this cell source. CMPCs isolated from human fetal heart were differentiated in vitro and examined using immunohistochemistry, Western blotting, RT-PCR, voltage clamp and current clamp techniques.
View Article and Find Full Text PDFBackground: MIF is a critical mediator of the host defense, and is involved in both acute and chronic responses in the lung. Neutralization of MIF reduces neutrophil accumulation into the lung in animal models. We hypothesized that MIF, in the alveolar space, promotes neutrophil accumulation via activation of the CD74 receptor on macrophages.
View Article and Find Full Text PDFThe role of autoantibodies in the pathogenesis of systemic lupus erythematosus (SLE) has not been completely defined. From more than a hundred autoantibodies described in SLE, relatively few have been associated with clinical manifestations. The glycan-binding proteins of the galectin family can modulate the immune system.
View Article and Find Full Text PDFDevelopment involves an interplay between various cell types from their birth to their disappearance by differentiation, migration, or death. Analyzing these interactions provides insights into their roles during the formation of a new organism. As a study tool for these interactions, we have created a model based on embryoid bodies (EBs) generated from mouse embryonic stem (mES) cells, which can be used to visualize the differentiation of mES cells into specific cell types while at the same time allowing controlled removal of this same cell population using an enzyme-prodrug approach.
View Article and Find Full Text PDFCyclooxygenase (COX) is the rate-limiting enzyme in the metabolic conversion of arachidonic acid to prostaglandins (PGs), including prostaglandin E(2) (PGE(2)), a major mediator of inflammation and angiogenesis. Herein, we report that macrophage migration inhibitory factor (MIF), a potent proinflammatory and growth-promoting factor found at elevated concentrations in the peritoneal fluid of women with endometriosis and active endometriosis lesions, acts directly on ectopic endometrial cells to stimulate the synthesis of COX-2, the inducible form of COX, and the release of PGE(2). MIF treatment strongly activated p38 and ERK MAPK, and specific inhibitors of both pathways completely blocked basal and MIF-induced PGE(2) synthesis.
View Article and Find Full Text PDFGalectins have been implicated in T cell homeostasis playing complementary pro-apoptotic roles. Here we show that galectin-8 (Gal-8) is a potent pro-apoptotic agent in Jurkat T cells inducing a complex phospholipase D/phosphatidic acid signaling pathway that has not been reported for any galectin before. Gal-8 increases phosphatidic signaling, which enhances the activity of both ERK1/2 and type 4 phosphodiesterases (PDE4), with a subsequent decrease in basal protein kinase A activity.
View Article and Find Full Text PDFBackground: Preoperative or postoperative radiotherapy reduces the risk of local recurrence in patients with operable rectal cancer. However, improvements in surgery and histopathological assessment mean that the role of radiotherapy needs to be reassessed. We compared short-course preoperative radiotherapy versus initial surgery with selective postoperative chemoradiotherapy.
View Article and Find Full Text PDFBackground: The links among smoking, inflammation, and cardiovascular disease (CVD) are well established. Several studies have demonstrated that quitting smoking reverses the risk of coronary heart disease within 5 to 10 years. However, the immediate effects of quitting smoking on inflammatory biomarkers associated with CVD risk have not been well described.
View Article and Find Full Text PDFTo date, there is no suitable in vitro model to study human adult cardiac cell biology. Although embryonic stem cells are able to differentiate into cardiomyocytes in vitro, the efficiency of this process is very low. Other methods to differentiate progenitor cells into beating cardiomyocytes rely on coculturing with rat neonatal cardiomyocytes, making it difficult to study human cardiomyocyte differentiation and (patho)physiology.
View Article and Find Full Text PDFMed Image Comput Comput Assist Interv
June 2010
We present an approach to derive patient specific coronary models from ECG-gated CTA data and their application for the alignment of CTA with mono-plane X-ray imaging during interventional cardiology. A 4D (3D+t) deformation model of the coronary arteries is derived by (i) extraction of a 3D coronary model at an appropriate cardiac phase and (ii) non-rigid registration of the CTA images at different ECG phases to obtain a deformation model. The resulting 4D coronary model is aligned with the X-ray data using a novel 2D+t/3D+t registration approach.
View Article and Find Full Text PDFEndocrinol Metab Clin North Am
December 2008
This article summarizes advances in the field of host-microbe interactions in the gut. The human gut is home to a complex community of microbes (the microbiota) that plays a critical role in host nutrient acquisition and metabolism, development of intestinal epithelial cells, and host immune system. Genetic background, nutritional status, and environmental factors influence the structure and function of the gut microbiota.
View Article and Find Full Text PDFRationale And Objectives: Our goal was to investigate the effects of changes that the prevalence of cancer in a population have on the probability of malignancy (PM) output and an optimal combination of a true-positive fraction (TPF) and a false-positive fraction (FPF) of a mammographic and sonographic automatic classifier for the diagnosis of breast cancer.
Materials And Methods: We investigate how a prevalence-scaling transformation that is used to change the prevalence inherent in the computer estimates of the PM affects the numerical and histographic output of a previously developed multimodality intelligent workstation. Using Bayes' rule and the binormal model, we study how changes in the prevalence of cancer in the diagnostic breast population affect our computer classifiers' optimal operating points, as defined by maximizing the expected utility.
Generation of a reference standard from multiple manually annotated datasets is a non-trivial problem. This paper discusses the weighted averaging of 3D open curves, which we used to generate a reference standard for vessel tracking data. We show how weighted averaging can be implemented by applying the Mean Shift algorithm to paths, and discuss the details of our implementation.
View Article and Find Full Text PDFThe existence of an increased risk of childhood leukaemia near nuclear installations is a recurrent issue. A review of the related epidemiological literature is presented here. Results for 198 nuclear sites throughout 10 countries were included in the review.
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