Gabrielle Sarlon

A switch toward angiostatic gene expression impairs the angiogenic properties of endothelial progenitor cells in low birth weight preterm infants.

Low birth weight (LBW) is associated with increased risk of cardiovascular diseases at adulthood. Nevertheless, the impact of LBW on the endothelium is not clearly established. We investigate whether LBW alters the angiogenic properties of cord blood endothelial colony forming cells (LBW-ECFCs) in 25 preterm neonates compared with 25 term neonates (CT-ECFCs). We observed that LBW decreased the number of colonies formed by ECFCs and delayed the time of appearance of their clonal progeny. LBW dramatically reduced LBW-ECFC capacity to form sprouts and tubes, to migrate and to proliferate in vitro. The angiogenic defect of LBW-ECFCs was confirmed in vivo by their inability to form robust capillary networks in Matrigel plugs injected in nu/nu mice. Gene profile analysis of LBW-ECFCs demonstrated an increased expression of antiangiogenic genes. Among them, thrombospondin 1 (THBS1) was highly expressed at RNA and protein levels in LBW-ECFCs. Silencing THBS1 restored the angiogenic properties of LBW-ECFCs by increasing AKT phosphorylation. The imbalance toward an angiostatic state provide a mechanistic link between LBW and the impaired angiogenic properties of ECFCs and allows the identification of THBS1 as a novel player in LBW-ECFC defect, opening new perspectives for novel deprogramming agents.

Surveillance des endoprothèses aortiques abdominales : intérêt de l’échographie-doppler standard et avec contraste

OBJECTIVE Long-term surveillance is needed after endovascular aneurysm repair to monitor the aneurysm and search for persistent endoleaks. Our aim was to compare follow-up with duplex ultrasound, with and without a new contrast agent to track endoleaks, versus computed tomography angiography taken as the gold standard. MATERIAL AND METHOD Patients treated with endograft were included prospectively from December 2005 to July 2006. Aortic duplex ultrasound and computed tomography were used to measure maximal aneurysm diameter and detect endoleaks. Patients with a high risk of endoleaks had a contrast-enhanced ultrasound with Sonovue (Bracco, Milan, Italy). We compared echographic and tomographic diameter and studied the sensitivity of ultrasound endoleak diagnosis. RESULTS Sixty-seven patients were included. There was a good correlation between maximum anteroposterior diameters (CCI=0.98) measured by ultrasound and tomography, as well as mean maximum cross section diameters (CCI=0.96). Compared to tomography, the sensitivity of ultrasound endoleaks diagnosis was 44% (kappa=0.58). Contrast injection improved this sensitivity significantly (p<0.001) (sensitivity=88%; kappa=0.72). CONCLUSION These findings confirmed the performance of our ultrasound method for endograft surveillance. Contrast-enhanced ultrasound significantly improves the sensitivity of detection of endoleaks. We suggest alternating ultrasound and tomographic exams. A unique report chart for use nationwide would be useful for standardizing follow-up.

Congenital Anomalies of Inferior Vena Cava in Young Patients with Iliac Deep Venous Thrombosis

Venous thromboembolism (VTE) in young patients is frequently associated with hereditary biological thrombophilia, autoimmune disorders, or neoplasia. Advances in venous ultrasound and contrast-enhanced computed tomography have allowed for the identification of inferior vena cava (IVC) anomalies as newly considered etiologic factor. We present two cases of VTE in young patients: the first case involves left IVC in a 22-year-old man and the second involves IVC atresia in a 39-year-old man. IVC anomalies should be identified in young patients with spontaneous VTE involving the iliac veins because they are at a high risk for thrombotic recurrence and adaptation to long periods of antithrombotic therapy.

Stem cell properties of peripheral blood endothelial progenitors are stimulated by soluble CD146 via miR-21: potential use in autologous cell therapy

Cell-based therapies constitute a real hope for the treatment of ischaemic diseases. One of the sources of endothelial progenitors for autologous cell therapy is Endothelial Colony Forming Cells (ECFC) that can be isolated from peripheral blood. However, their use is limited by their low number in the bloodstream and the loss of their stem cell phenotype associated with the acquisition of a senescent phenotype in culture. We hypothesized that adding soluble CD146, a novel endothelial growth factor with angiogenic properties, during the isolation and growth procedures could improve their number and therapeutic potential. Soluble CD146 increased the number of isolated peripheral blood ECFC colonies and lowered their onset time. It prevented cellular senescence, induced a partial mesenchymal phenotype and maintained a stem cell phenotype by stimulating the expression of embryonic transcription factors. These different effects were mediated through the induction of mature miR-21. When injected in an animal model of hindlimb ischaemia, sCD146-primed ECFC isolated from 40 ml of blood from patients with peripheral arterial disease were able to generate new blood vessels and restore blood flow. Treatment with sCD146 could thus constitute a promising strategy to improve the use of autologous cells for the treatment of ischaemic diseases.

Results of EVAR in patients Followed up for at Least eight Years

favorable for FBS had an elective intervention. Two (14%) patients had emergency surgery (acute rupture and painful aneurysm with covered rupture). The data are expressed in medians and range. Results: The series included 13 men (93%) and one woman (7%), with a median age of 85 years (65-90). The diameter of the JRAAA was of 61 mm (58-80). Twenty-six target arteries were treated (1.9 with patient; 19 renal arteries, six superior mesenteric arteries and one celiac artery) revascularized by 22 (85%) chimneys and 4 (15%) periscopes. Intraoperatively, an ilio-renal bridging was carried out to recover an occluded chimney. Three type Ia endoleaks were noted and followed up. The operative time was 280 min (180-580) and 120 mL (20240) of contrast medium were used. Postoperatively, the two patients operated in emergency died (multivisceral failure [MVF]) and major stroke). The mortality of the elective CHIMPS was 8% (1/12): one patient with end stage renal failure died of MVF due to cholesterol embolisms. Another patient presented a partially regressive acute renal failure and a limb was stented at D13. With a 12 months (2-37) follow-up, one patient died of a non-vascular cause. No JRAAA increased in diameter. The type Ia endoleaks had regressed and three patients (27%) presented a type II endoleak. The primary patency of the target arteries was 81% (three renal occlusions) and four patients (36%) had a decrease> 20% in glomerular filtration rate. Conclusion: The CHIMPS can be proposed in patients accessible to FBS but they remain debatable in emergency. The deterioration of the renal function during the follow-up is alarming. This problem being also observed in the literature after FBS, a comparative study with more patients should be conducted.

In-situ Revascularization with Silver Coated Grafts Soaked in Rifampin for Infection of the Abdominal Aorta: A Single Center Experience

Objectives: Severe chronic renal insufficiency is a major limitation for the endovascular treatment of aorto-iliac aneurysms (EVAR). MRI imaging can bring an important alternative to angio-CT. The aim of this study was to evaluate the feasibility of preoperative MRI and computer processing to minimize the use of iodized contrast during EVAR. Materials and Methods: From October 2013 to November 2014, each patient requiring EVAR and presenting a severely chronic impaired renal function was submitted to a specific preoperative imaging protocol. Preoperative MRI was carried out according to a protocol adapted with a reinforcement of the osseous relief. Preoperative 3D imaging was linked with the rotational radiographic imaging (3D) obtained on the operating table by using the Artis zeego Fusion program (Siemens AG, Forchheim, Germany). The fused image was applied for the vascular cartography for EVAR and the associated procedures (angioplasties, embolization). The correction of the positioning of the ‘‘target’’ arteries was carried out by the positioning of the guidewire or the injection of a minimal volume of contrast medium. The distances of correction were analyzed. Final control was carried out by ultrasound. Results: Eleven patients (six women, 73±8 years) were treated by applying this technique. The filtration rate (eGFR) was 16.5 mL/min/1.73 m. The mean volume of contrast medium used during the procedure was 7mL (15-5). The implantation of the abdominal stentgraft guided by the MRI fusion of image was feasible in all the patients. No peroperative type I endoleak was observed on ultrasound scanning. A wound of a branch of a renal artery required a selective embolization. Except for this last patient, no deterioration of the renal function was observed after one month of follow-up. The average error of positioning of the mapping cartography was 3 mm for the renal artery and 8.5 mm for the hypogastric artery. Conclusion: The feasibility and the precision of endovascular guiding based on fused MRI images are good in the