Autologous transplantation of culture-born myofibroblasts into intact and injured rabbit ligaments

Purpose: The myofibroblast, a contractile fibroblastic cell expressing α-smooth muscle actin (α-SMA), has been reported to play a role in ligament healing. The aim of this study was to evaluate the feasibility of transplanting culture-derived myofibroblasts in injured rabbit medial collateral ligaments (MCL) and in intact anterior cruciate ligaments (ACL). Methods: Fibroblasts isolated from the iliotibial band were cultured in the presence of transforming growth factor beta-1 (TGF-β1) for fivedays and analysed for α-SMA expression. In a concentration of TGF-β1 ≥ 10ng/ml, the differentiation rate into myofibroblast was 90%. After labelling with PKH26, α-SMA -positive cells were transplanted in intact ACL and in injured MCL of ten rabbits. Results: Survival of PKH-26+ cells was seen in all intact and damaged ligaments one day after injection. The density of PKH-26+ cells had decreased at seven days postinjection in both ligaments. Double-positive PKH-26+/α-SMA+ cells were only observed in injured MCL at sevendays postinjection. Moreover, we found that genetically modified fibroblasts differentiate into myofibroblasts and can be transplanted into ligaments. Conclusions: Our data demonstrate that culture-born myofibroblasts survive and maintain α-SMA expression up to one week after transplantation. This study provides the first insight into the feasibility of transplanted mechanically active cells for ligament reconstructio

Thrombus burden management during primary coronary bifurcation intervention: a new experimental bench model

Background: Management of thrombus burden during primary percutaneous coronary intervention (pPCI) is a key-point, given the high risk of stent malapposition and/or thrombus embolization. These issues are especially important if pPCI involves a coronary bifurcation. Herein, a new experimental bifurcation bench model to analyze thrombus burden behavior was developed. Methods: On a fractal left main bifurcation bench model, we generated standardized thrombus with human blood and tissue factor. Three provisional pPCI strategies were compared (n = 10/group): 1) balloon-expandable stent (BES), 2) BES completed by proximal optimizing technique (POT), and 3) nitinol self-apposing stent (SAS). The embolized distal thrombus after stent implantation was weighed. Stent apposition and thrombus trapped by the stent were quantified on 2D-OCT. To analyze final stent apposition, a new OCT acquisition was performed after pharmacological thrombolysis. Results: Trapped thrombus was significantly greater with isolated BES than SAS or BES+POT (18.8 ± 5.8% vs. 10.3 ± 3.3% and 6.2 ± 2.1%, respectively; p < 0.05), and greater with SAS than BES+POT (p < 0.05). Isolated BES and SAS tended show less embolized thrombus than BES+POT (5.93 ± 4.32 mg and 5.05 ± 4.56 mg vs. 7.01 ± 4.32 mg, respectively; p = NS). Conversely, SAS and BES+POT ensured perfect final global apposition (0.4 ± 0.6% and 1.3 ± 1.3%, respectively, p = NS) compared to isolated BES (74.0 ± 7.6%, p < 0.05). Conclusions: This first experimental bench model of pPCI in a bifurcation quantified thrombus trapping and embolization. BES provided the best thrombus trapping, while SAS and BES+POT achieved better final stent apposition. These factors should be taken into account in selecting revascularization strategy

Beta-blocker management in patients admitted for acute heart failure and reduced ejection fraction: a review and expert consensus opinion

The role of the beta-adrenergic signaling pathway in heart failure (HF) is pivotal. Early blockade of this pathway with beta-blocker (BB) therapy is recommended as the first-line medication for patients with HF and reduced ejection fraction (HFrEF). Conversely, in patients with severe acute HF (AHF), including those with resolved cardiogenic shock (CS), BB initiation can be hazardous. There are very few data on the management of BB in these situations. The present expert consensus aims to review all published data on the use of BB in patients with severe decompensated AHF, with or without hemodynamic compromise, and proposes an expert-recommended practical algorithm for the prescription and monitoring of BB therapy in critical settings

Comparison of clinical characteristics and healthcare resource use of pediatric chronic and non-chronic critically ill patients in intensive care units: a retrospective national registry study

IntroductionChronic critically ill patients (CCI) in pediatric intensive care unit (PICU) are at risk of negative health outcomes, and account for a considerable amount of ICU resources. This study aimed to (a) describe the prevalence of CCI children, (b) compare their clinical characteristics and ICU resources use with non-CCI children, and (c) identify associated risk factors of CCI.MethodsA retrospective national registry study including 2015–2017 data from the eight Swiss PICUs of five tertiary and three regional hospitals, admitting a broad case-mix of medical and surgical patients, including pre- and full-term infants. CCI patients were identified using an adapted definition: PICU length of stay (LOS) ≥8 days and dependence on ≥1 PICU technology.ResultsOut of the 12,375 PICU admissions, 982 (8%) were CCI children and compared to non-CCI children, they were younger (2.8 vs. 6.7 months), had more cardiac conditions (24% vs. 12%), and higher mortality rate (7% vs. 2%) (p < 0.001). Nursing workload was higher in the CCI compared to the non-CCI group (22 [17–27]; 21 [16–26] respectively p < 0.001). Factors associated with CCI were cardiac (aOR = 2.241) and neurological diagnosis (aOR = 2.062), surgery (aORs between 1.662 and 2.391), ventilation support (aOR = 2.278), high mortality risk (aOR = 1.074) and agitation (aOR = 1.867).Conclusionthe results confirm the clinical vulnerability and the complexity of care of CCI children as they were defined in our study. Early identification and adequate staffing is required to provide appropriate and good quality care

P2 receptors in atherosclerosis and postangioplasty restenosis

Atherosclerosis is an immunoinflammatory process that involves complex interactions between the vessel wall and blood components and is thought to be initiated by endothelial dysfunction [Ross (Nature 362:801–09, 1993); Fuster et al. (N Engl J Med 326:242–50, 1992); Davies and Woolf (Br Heart J 69:S3–S11, 1993)]. Extracellular nucleotides that are released from a variety of arterial and blood cells [Di Virgilio and Solini (Br J Pharmacol 135:831–42, 2002)] can bind to P2 receptors and modulate proliferation and migration of smooth muscle cells (SMC), which are known to be involved in intimal hyperplasia that accompanies atherosclerosis and postangioplasty restenosis [Lafont et al. (Circ Res 76:996–002, 1995)]. In addition, P2 receptors mediate many other functions including platelet aggregation, leukocyte adherence, and arterial vasomotricity. A direct pathological role of P2 receptors is reinforced by recent evidence showing that upregulation and activation of P2Y2 receptors in rabbit arteries mediates intimal hyperplasia [Seye et al. (Circulation 106:2720–726, 2002)]. In addition, upregulation of functional P2Y receptors also has been demonstrated in the basilar artery of the rat double-hemorrhage model [Carpenter et al. (Stroke 32:516–22, 2001)] and in coronary artery of diabetic dyslipidemic pigs [Hill et al. (J Vasc Res 38:432–43, 2001)]. It has been proposed that upregulation of P2Y receptors may be a potential diagnostic indicator for the early stages of atherosclerosis [Elmaleh et al. (Proc Natl Acad Sci U S A 95:691–95, 1998)]. Therefore, particular effort must be made to understand the consequences of nucleotide release from cells in the cardiovascular system and the subsequent effects of P2 nucleotide receptor activation in blood vessels, which may reveal novel therapeutic strategies for atherosclerosis and restenosis after angioplasty

Microvesicles in vascular homeostasis and diseases. Position Paper of the European Society of Cardiology (ESC) Working Group on Atherosclerosis and Vascular Biology

Microvesicles are members of the family of extracellular vesicles shed from the plasma membrane of activated or apoptotic cells. Microvesicles were initially characterised by their pro-coagulant activity and described as "microparticles". There is mounting evidence revealing a role for microvesicles in intercellular communication, with particular relevance to hemostasis and vascular biology. Coupled with this, the potential of microvesicles as meaningful biomarkers is under intense investigation. This Position Paper will summarise the current knowledge on the mechanisms of formation and composition of microvesicles of endothelial, platelet, red blood cell and leukocyte origin. This paper will also review and discuss the different methods used for their analysis and quantification, will underline the potential biological roles of these vesicles with respect to vascular homeostasis and thrombosis and define important themes for future research

Regulation of the mitochondrial permeability transition pore and myocardial reperfusion injuries

L'infarctus du myocarde est la première cause de mortalité dans le monde. La reperfusion précoce est le traitement central de la prise en charge thérapeutique. Mais bien que salvatrice, la reperfusion s'accompagne elle-même de lésion dite de reperfusion. La mitochondrie et l'ouverture du pore de transition de perméabilité mitochondriale (mPTP) sont au centre de ces lésions de reperfusion. Le dysfonctionnement mitochondrial et la nécrose entraine par ailleurs une intense réponse inflammatoire locale et systémique. Le post-conditionnement ischémique et pharmacologique (par la cyclosporine A, CsA) constitue une voie de recherche importante afin de limiter les lésions de reperfusion. Mes travaux de thèse se sont attachés à étudier le rôle de la Sirtuine 3 dans la cardioprotection ainsi que d'étudier la réponse inflammatoire locale et systémique induite par l'ischémie/reperfusion (I/R) myocardique.Nous avons précisé le mécanisme d'action du post-conditionnement, qui semble médié par l'activation de la sirtuine 3 et la désacétylation de la cyclophiline D qui contribue à inhiber l'ouverture du mPTP. Nous avons ensuite montré que l'I/R myocardique induisait une intense réponse inflammatoire chez l'homme avec un rôle particulier d'IL-17A, IL-6, IL-8 et IL-10. Cependant, cette réponse inflammatoire n'était pas modifiée par l'utilisation de CsA. Enfin, nous avons pu montrer que le facteur induit par l'hypoxie (HIF-1a), qui est surexprimé lors de l'I/R est un important activateur la réponse inflammatoire, notamment sur l'inflammasome, et que le Nicotinamide Mononucléotide possède un rôle anti-inflammatoire en empêchant la stabilisation de HIF-1a. Tous ces éléments sont autant de cibles thérapeutiques potentielles à développer avec de nouvelles étudesMyocardial infarction (MI) is the first cause of death in the world. Reperfusion is the key treatment of MI. However, reperfusion can cause reperfusion injuries. Mitochondria and mitochondrial permeablility transition pore are the target of reperfusion injuries. Mitochondrial dysfonction and necrosis lead to an intense local and systemic inflammation. Ischemic post-conditioning (PC) and pharmacologic PC (with cyclosporine A, CsA) are used to limit reperfusion injuries. During my thesis, I worked on cardioprotective effet of sirtuin 3 and I studied inflammation induced by myocardial ischemia/reperfusion (I/R). I have shown that ischemic PC involve sirtuin 3 and deacetylation of cyclophilin D. I demonstrated that myocardial I/R induce an intense inflammatory response in Human with a key role of IL-17A, IL-6, IL-8 and IL-10. However, this inflammatory response is not modulated by the administration of CsA. A least, we studied the role of HIF-1a that is over expressed during I/R. We showed that HIF-1a activate inflammasome and the secretion of IL-1beta and IL-18. Furthermore, Nicotinamied Mononucleotide has anti-inflammatory effets with an action of HIF-1a. Taken together, these data contribute to develop new target for cardioprotectio

Circadian rhythm and ischaemia-reperfusion injury

International audienc