References of "COURTOIS, Audrey"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailIgG4-related disease causing rapid evolution of a severe aortic valvular stenosis
BRULS, Samuel ULg; Courtois, Audrey ULg; DELVENNE, Philippe ULg et al

in The Annals of Thoracic Surgery (2016)

Detailed reference viewed: 18 (5 ULg)
Full Text
Peer Reviewed
See detailMultimodality imaging assessment of the deleterious role of the intraluminal thrombus on the growth of abdominal aortic aneurysm in a rat model
NCHIMI LONGANG, Alain ULg; Courtois, Audrey ULg; EL HACHEMI, Mounia ULg et al

in European Radiology (2016), 26

Objectives To evaluate imaging changes occurring in a rat model of elastase-induced abdominal aortic aneurysm (AAA), with emphasis on the intraluminal thrombus (ILT) occurrence. Methods The post-induction ... [more ▼]

Objectives To evaluate imaging changes occurring in a rat model of elastase-induced abdominal aortic aneurysm (AAA), with emphasis on the intraluminal thrombus (ILT) occurrence. Methods The post-induction growth of the AAA diameter was characterized using ultrasound in 22 rats. ILT was reported on 13 rats that underwent 14 magnetic resonance imaging (MRI) 2-18 days post-surgery, and on 10 rats that underwent 18 fluoro-deoxyglucose (FDG) positron emission tomography (PET)/microcomputed tomography examinations 2-27 days post-surgery. Logistic regressions were used to establish the evolution with time of AAA length, diameter, ILT thickness, volume, stratification, MRI and FDG PET signalling properties, and histological assessment of inflammatory infiltrates. Results All of the following significantly increased with time post-induction (p < 0.001): AAA length, AAA diameter, ILT maximal thickness, ILT volume, ILT iron content and related MRI signalling changes, quantitative uptake on FDG PET, and the magnitude of inflammatory infiltrates on histology. However, the aneurysm growth peak followed occurrence of ILT approximately 6 days after elastase infusion. Conclusion Our model emphasizes that occurrence of ILT precedes AAA peak growth. Aneurysm growth is associated with increasing levels of iron, signalling properties changes in both MRI and FDG PET, relating to its biological activities. [less ▲]

Detailed reference viewed: 81 (16 ULg)
Full Text
Peer Reviewed
See detail(Tissue PET) vascularmetabolic imaging and peripheral plasma biomarkers in the evolution of chronic aortic dissections
SAKALIHASAN, Natzi ULg; NIENABER, Christoph; HUSTINX, Roland ULg et al

in European Heart Journal - Cardiovascular Imaging (2015)

Enhanced FDG uptake may be considered as a complementary imaging marker associated with secondary complications in type B dissections. During follow-up, aneurysmal progression is related to PET/CT and ... [more ▼]

Enhanced FDG uptake may be considered as a complementary imaging marker associated with secondary complications in type B dissections. During follow-up, aneurysmal progression is related to PET/CT and biomarkers of thrombus renewal and lysis. [less ▲]

Detailed reference viewed: 81 (28 ULg)
Full Text
Peer Reviewed
See detailGene Expression Study in Positron Emission Tomography–Positive Abdominal Aortic Aneurysms Identifies CCL18 as a Potential Biomarker for Rupture Risk
Courtois, Audrey ULg; Nusgens-Richelle, Betty ULg; HUSTINX, Roland ULg et al

in Molecular Medicine (2015)

Rupture of abdominal aortic aneurysm (AAA) is a cause of significant mortality and morbidity in ageing populations. Uptake of 18-fluorodeoxyglucose (FDG) detected by positron emission tomography (PET) is ... [more ▼]

Rupture of abdominal aortic aneurysm (AAA) is a cause of significant mortality and morbidity in ageing populations. Uptake of 18-fluorodeoxyglucose (FDG) detected by positron emission tomography (PET) is observed in the wall of 12% of AAA (A+), most of them being symptomatic. We previously showed that the metabolically active areas displayed adventitial inflammation, medial degeneration and molecular alterations prefacing wall rupture. The aim of this study was to identify new factors predictive of rupture.Transcriptomic analyses were performed in the media and adventitia layers from three types of samples: AAA without (A0) and with FDG uptake (A+), both at the positive spot (A+Pos) and at a paired distant negative site (A+Neg) of the same aneurysm. Follow-up studies included RT-PCR, immunohistochemical staining and ELISA. A large number of genes, including matrix metalloproteinases, collagens and cytokines as well as genes involved in osteochondral development, were differentially expressed in the A+Pos as compared to A+Neg. Moreover, a series of genes, notably CCL18, was differentially expressed both in the A+Neg and A+Pos as compared to the A0. A significant increase of CCL18 was also found at the protein level in the aortic wall and in peripheral blood of A+ patients as compared to A0.In conclusion, new factors, including CCL18, involved in the progression of AAA and, potentially, in their rupture were identified by a genome-wide analysis of PET-positive and negative human aortic tissue samples. Further work is needed to study their role in AAA destabilization and weakening. [less ▲]

Detailed reference viewed: 53 (14 ULg)
Full Text
Peer Reviewed
See detail18F-FDG PET/CT in the Management of Aortitis.
Bruls, Samuel; Courtois, Audrey ULg; Nusgens-Richelle, Betty ULg et al

in Clinical nuclear medicine (2015)

BACKGROUND: Aortitis is a generic term defined as an inflammatory condition involving the aortic wall, of infectious or noninfectious origin. This inflammatory process may deteriorate the aortic wall ... [more ▼]

BACKGROUND: Aortitis is a generic term defined as an inflammatory condition involving the aortic wall, of infectious or noninfectious origin. This inflammatory process may deteriorate the aortic wall, resulting in potentially life-threatening vascular complications. Therefore, it is important to establish a diagnosis as early as possible. PATIENTS AND METHODS: During a 4-year period, 428 consecutive patients referred to our department for aortic diseases underwent FDG PET/CT examinations. Among these, 18 patients (4.2%) were suspected to have aortitis. All of them had an initial positive FDG PET/CT uptake occurring in the aorta and major branches as evaluated by visual analysis of images and assessed with the final diagnosis of aortitis. During follow-up, after surgery and/or upon immunosuppressive treatment, each of these patients underwent a second PET/CT that was compared with the initial evaluation. In all cases, normalization of FDG uptake was correlated with clinical improvement. CONCLUSIONS: Our study aimed to illustrate the potential clinical value of functional monitoring with PET/CT in the management of aortitis. FDG PET/CT constitutes a valuable imaging modality to establish an early diagnosis, monitor disease progression and treatment, and evaluate vascular complication and relapse. We highlight the importance of an early detection of inflammatory large-vessel pathology, which may represent a major threat. [less ▲]

Detailed reference viewed: 95 (17 ULg)
Full Text
Peer Reviewed
See detailCirculating miRNA signature of PET-positive abdominal aortic aneurysms: new potential predictors of rupture
Courtois, Audrey ULg; Nusgens-Richelle, Betty ULg; HUSTINX, Roland ULg et al

in Atherosclerosis, Thrombosis and Vascular Biology (2015)

Detailed reference viewed: 31 (12 ULg)
Full Text
Peer Reviewed
See detailSex Differences in Abdominal Aortic Aneurysm: the Role of Sex Hormones.
Makrygiannis, Georgios ULg; Courtois, Audrey ULg; Drion, Pierre ULg et al

in Annals of vascular surgery (2014), 28(8), 1946-1958

Abdominal aortic aneurysm (AAA) is a complex multifactorial disease with genetic and environmental components. AAA is more common in males, whereas women have a greater risk of rupture and more frequently ... [more ▼]

Abdominal aortic aneurysm (AAA) is a complex multifactorial disease with genetic and environmental components. AAA is more common in males, whereas women have a greater risk of rupture and more frequently have concomitant thoracic aortic aneurysms. Moreover, women are diagnosed with AAA about 10 years later and seem to be protected by female sex hormones. In this MEDLINE-based review of literature we examined human and animal, in vivo and in vitro studies, to further deepen our understanding of the sexual dimorphism of AAA. We focus on the role of sex hormones during the formation and growth of AAA. Endogenous estrogens and exogenous 17beta-estradiol were found to exert favorable actions protecting from AAA in animal models, whereas exogenous hormone replacement therapy in humans had inconclusive results. Androgens, known to have detrimental effects in the vasculature, in sufficient levels maintain the integrity of the aortic wall through their anabolic actions and act differentially in males and females, whereas lower levels of testosterone have been associated with AAA in humans. In conclusion, sex differences remain an important area of AAA research, but further studies especially in humans are needed. Furthermore, differential molecular mechanisms of sex hormones constitute a potential therapeutic target for AAA. [less ▲]

Detailed reference viewed: 98 (44 ULg)
Full Text
Peer Reviewed
See detailIntérèts de la tomographie à émission de positons dans le suivi et le pronostic des anévrysmes de l'aorte abdominale
Courtois, Audrey ULg; Nusgens-Richelle, Betty ULg; Hustinx, Roland ULg et al

in Revue medicale de Liege (2014), 69 Spec No

Rupture of abdominal aortic aneurysm (AAA) remains a major cause of death in the elderly. Its prediction is a serious challenge for public health. Despite its regular use to identify patients requiring ... [more ▼]

Rupture of abdominal aortic aneurysm (AAA) remains a major cause of death in the elderly. Its prediction is a serious challenge for public health. Despite its regular use to identify patients requiring surgical treatment, the diameter of AAA is not a sufficiently precise and reliable parameter for discriminating aneurysms at high risk of rupture. A better targeting of high risk patients needs understanding in deep the processes and mechanisms directing wall rupture. Inflammation is a significant element in the progression ofAAA and can be visualized using medical imaging techniques such as positron emission tomography (PET) using a glucose derivative (FDG) as radiotracer. Studies conducted in our department have established a relationship between PET positivity and the presence of symptoms such as accelerated growth of the aneurysm or pain, signs generally considered as predictive of rupture. Moreover, activation of leukocytes coupled to cellular and molecular alterations of the aneurysmal wall in the sites of FDG uptake may lead to its instability and incompetence to resist blood pressure and rupture. PET therefore represents a new original exploration method to characterize the severity of AAA progression allowing to assess the need for a surgical treatment much better than does the AAA diameter. [less ▲]

Detailed reference viewed: 43 (13 ULg)
Full Text
Peer Reviewed
See detail18F-FDG Uptake Assessed by PET/CT in Abdominal Aortic Aneurysms Is Associated with Cellular and Molecular Alterations Prefacing Wall Deterioration and Rupture.
Courtois, Audrey ULg; Richelle, Betty ULg; Hustinx, Roland ULg et al

in Journal of Nuclear Medicine (The) (2013), 54

Rupture of abdominal aortic aneurysms (AAAs) leads to a significant morbidity and mortality in aging populations, and its prediction would be most beneficial to public health. Spots of positive uptake of ... [more ▼]

Rupture of abdominal aortic aneurysms (AAAs) leads to a significant morbidity and mortality in aging populations, and its prediction would be most beneficial to public health. Spots of positive uptake of 18F-FDG detected by PET are found in 12% of AAA patients (PET+), who are most often symptomatic and at high rupture risk. Comparing the 18F-FDG-positive site with a negative site from the same aneurysm and with samples collected from AAA patients with no 18F-FDG uptake should allow the discrimination of biologic alterations that would help in identifying markers predictive of rupture. METHODS: Biopsies of the AAA wall were obtained from patients with no 18F-FDG uptake (PET0, n = 10) and from PET+ patients (n = 8), both at the site of positive uptake and at a distant negative site of the aneurysmal wall. Samples were analyzed by immunohistochemistry, quantitative real-time polymerase chain reaction, and zymography. RESULTS: The sites of the aneurysmal wall with a positive 18F-FDG uptake were characterized by a strikingly increased number of adventitial inflammatory cells, highly proliferative, and by a drastic reduction of smooth muscle cells (SMCs) in the media as compared with their negative counterpart and with the PET0 wall. The expression of a series of genes involved in the maintenance and remodeling of the wall was significantly modified in the negative sites of PET+, compared with the PET0 wall, suggesting a systemic alteration of the aneurysmal wall. Furthermore, a striking increase of several matrix metalloproteinases (MMPs), notably the MMP1 and MMP13 collagenases, was observed in the positive sites, mainly in the adventitia. Moreover, PET+ patients were characterized by a higher circulating C-reactive protein. CONCLUSION: Positive 18F-FDG uptake in the aneurysmal wall is associated with an active inflammatory process characterized by a dense infiltrate of proliferating leukocytes in the adventitia and an increased circulating C-reactive protein. Moreover, a loss of SMC in the media and alterations of the expression of genes involved in the remodeling of adventitia and collagen degradation potentially participate in the weakening of the aneurysmal wall preceding rupture. [less ▲]

Detailed reference viewed: 114 (42 ULg)
Full Text
See detailPathobiologie des anévrysmes de l'aorte abdominale: intérêts de la tomographie par émission de positons
Courtois, Audrey ULg

Doctoral thesis (2013)

Les anévrysmes de l’aorte abdominale correspondent à une dilation de l’aorte infra-rénale de plus de 30 mm. Le risque de rupture d’un anévrysme a été longtemps considéré comme étant dépendant de son ... [more ▼]

Les anévrysmes de l’aorte abdominale correspondent à une dilation de l’aorte infra-rénale de plus de 30 mm. Le risque de rupture d’un anévrysme a été longtemps considéré comme étant dépendant de son diamètre, un paramètre qui constitue toujours le critère décisionnel le plus courant pour le traitement chirurgical des AAA. De nombreuses études ont cependant montré que la taille de l’anévrysme ne devait pas être le seul facteur à prendre en compte puisque certains anévrysmes de grande taille peuvent rester stables pendant des années sans signe de rupture tandis que d’autres rompent alors qu’ils n’avaient pas atteint une taille critique. Une accélération de la croissance ou l’apparition de douleurs doivent en revanche être considérés comme des signes alarmants. Il n’existe à l’heure actuelle aucun moyen ni marqueur fiable permettant de prédire l’évolution d’un anévrysme. La base de notre travail repose sur des études cliniques originales, réalisées dans le département de chirurgie cardiovasculaire en collaboration avec des services de médecine nucléaire, qui visaient à étudier la captation de 18F-Fluorodéoxyglucose ou FDG dans la paroi anévrysmale par tomographie à émission de positons couplé à un scanner ou PET/CT. D’abord limitée à quelques dizaines de patients, puis ensuite élargie plus récemment à quelques 400 cas, cette technique d’imagerie fonctionnelle a mis en évidence une captation de FDG reflétant une hyperactivité métabolique dans la paroi anévrysmale d’un nombre significatif de patients. Il a pu être établi que la captation de FDG au sein de l’anévrysme était associée à un taux de croissance accéléré et à la présence de symptômes, et qu’elle concordait parfois avec le site de rupture. Ces observations ont permis d’émettre l’hypothèse qu’une captation de FDG au sein de la paroi anévrysmale était synonyme de plus grande instabilité et d’un risque de rupture plus élevé. L’objectif majeur des travaux décrits dans ce mémoire était donc de comparer les altérations tissulaires, cellulaires et moléculaires présentes au sein de trois types d’échantillons anévrysmaux : les sites hypermétaboliques positifs au FDG, les zones quiescentes prélevées dans le même anévrysme à distance des sites de captation de FDG et des prélèvements réalisés sur des anévrysmes quiescents dans leur totalité. Cette approche devait nous permettre d’identifier des processus pathobiologiques locaux et globaux affectant la stabilité de la paroi aortique. Un premier volet de nos travaux a consisté à créer une banque d’échantillons biologiques (sang, pièces chirurgicales) provenant de patients suivis au moyen du PET/CT et atteints de différentes pathologies vasculaires. Dans la grande majorité des cas, ces échantillons ont été prélevés chez des patients souffrant d’un AAA soit quiescent (A0) ou présentant une zone hypermétabolique (A+). Dans ce dernier cas, les prélèvements de paroi anévrysmale ont été réalisés au site de fixation du FDG (A+pos) et dans une zone inactive située à distance de celui-ci (A+neg). Ces différents échantillons ont fait l’objet d’une étude histologique et biochimique des deux couches principales de la paroi : la media et l’adventice. Des altérations significatives susceptibles de représenter des processus avant-coureurs de la rupture ont été mises en évidence au sein du site de fixation du FDG, dont un infiltrat inflammatoire plus important, une perte des cellules contractiles de la media et un remodelage plus important de la matrice extracellulaire. De plus, des altérations de la paroi entière de l’anévrysme A+ sont également observées, suggérant ainsi des atteintes à la fois locales et systémiques. Afin d’élargir notre champ d’investigation, une analyse trancriptomique globale par micro-array a été réalisée sur ces différents échantillons. Nous avons ainsi pu déterminer de nouveaux facteurs surexprimés au niveau du site de captation de FDG et potentiellement impliqués dans l’instabilité de la paroi. Des facteurs modulés tant au site de captation de FDG qu’à distance de celui-ci au sein du même anévrysme pourraient constituer des biomarqueurs potentiels du développement et de la fragilisation de l’anévrysme dans son ensemble. [less ▲]

Detailed reference viewed: 12 (0 ULg)
Full Text
See detailExtracellular matrix proteins in normal and aneurysmal aorta
Lapière, Charles; Courtois, Audrey ULg; Nusgens-Richelle, Betty ULg

in SAKALIHASAN, Natzi; Kuivaniemi, Helena; Michel, Jean-Baptiste (Eds.) Aortic aneurysms: new insights into an old problem (2008)

Detailed reference viewed: 9 (0 ULg)