Clinical, biological, and genetic features in an afibrinogenemia patient series in Algeria.

Introduction: The incidence of afibrinogenemia had not been previously reported in Algeria. Afibrinogenemia patients are prone to both haemorrhagic and thrombotic complications. Predictive markers of thrombosis in afibrinogenemia patients are not existent.

Real-world use of idarucizumab for dabigatran reversal in three cases of serious bleeding.

Bleeding is a rare complication of direct oral anticoagulant potentially associated with high mortality rates. Biological monitoring is necessary for more than 24 h after idarucizumab antidote therapy in case of bleeding with dabigatran therapy.

Osteoprotegerin regulates cancer cell migration through SDF-1/CXCR4 axis and promotes tumour development by increasing neovascularization.

We previously reported that OPG is involved in ischemic tissue neovascularization through the secretion of SDF-1 by pretreated-OPG endothelial colony-forming cells (ECFCs). As the vascularization is one of the key factor influencing the tumour growth and cancer cell dissemination, we investigated whether OPG was able to modulate the invasion of human MNNG-HOS osteosarcoma and DU145 prostate cancer cell lines in vitro and in vivo. Cell motility was analysed in vitro by using Boyden chambers.

Low-Molecular-Weight Fucoidan Induces Endothelial Cell Migration via the PI3K/AKT Pathway and Modulates the Transcription of Genes Involved in Angiogenesis.

Low-molecular-weight fucoidan (LMWF) is a sulfated polysaccharide extracted from brown seaweed that presents antithrombotic and pro-angiogenic properties. However, its mechanism of action is not well-characterized. Here, we studied the effects of LMWF on cell signaling and whole genome expression in human umbilical vein endothelial cells and endothelial colony forming cells.

Fucoidan Stimulates Monocyte Migration via ERK/p38 Signaling Pathways and MMP9 Secretion.

Critical limb ischemia (CLI) induces the secretion of paracrine signals, leading to monocyte recruitment and thereby contributing to the initiation of angiogenesis and tissue healing. We have previously demonstrated that fucoidan, an antithrombotic polysaccharide, promotes the formation of new blood vessels in a mouse model of hindlimb ischemia. We examined the effect of fucoidan on the capacity of peripheral blood monocytes to adhere and migrate.

[Thrombopathy induced by selective serotonin reuptake inhibitors: a case report].

We report the case of a 20 years old man presenting two episodes of hematemesis. The patient was known to suffer from depression and was treated with sertraline (Zoloft®) for 6 months at the dosage of 100 mg/day. No endoscopic and radiological abnormality was found.

Tie2-dependent deletion of α6 integrin subunit in mice reduces tumor growth and angiogenesis.

The α6 integrin subunit (α6) has been implicated in cancer cell migration and in the progression of several malignancies, but its role in tumor angiogenesis is unclear. In mice, anti-α6 blocking antibodies reduce tumor angiogenesis, whereas Tie1-dependent α6 gene deletion enhances neovessel formation in melanoma and lung carcinoma. To clarify the discrepancy in these results we used the cre-lox system to generate a mouse line, α6fl/fl‑Tie2Cre(+), with α6 gene deletion specifically in Tie2-lineage cells: endothelial cells, pericytes, subsets of hematopoietic stem cells, and Tie2-expressing monocytes/macrophages (TEMs), known for their proangiogenic properties.

[Accreditation of automated complete blood count by the LH750 Analyzer (Beckman Coulter) in Georges Pompidou Hospital (Paris, France)].

Preliminary evaluation of quantitative clinical laboratory measurements is a prerequisite for the accreditation of clinical laboratories, according to the French Committee of Accreditation guidelines following the European reference Standard EN ISO 15189. Numerous papers have been published regarding biochemistry and immunology. However, data are lacking for automated complete blood count accreditation.

The in vitro and in vivo effects of a low-molecular-weight fucoidan on the osteogenic capacity of human adipose-derived stromal cells.

Human adipose-derived stromal cells (hASCs) may hold potential for bone tissue engineering. Osteogenic differentiation of these cells is crucial to bone formation. Low-molecular-weight fucoidan (LMWF) is a sulfated polysaccharide that potentiates several growth factors, including pro-angiogenic growth factors.

Evaluation of recombinant activated factor VII, prothrombin complex concentrate, and fibrinogen concentrate to reverse apixaban in a rabbit model of bleeding and thrombosis.

Background: As all anticoagulants, apixaban exposes to a bleeding risk, thus an effective way to reverse its effects is needed. Objectives were to study efficacy and safety of recombinant activated factor VII (rFVIIa), prothrombin complex concentrate (PCC), and fibrinogen concentrate (Fib) to reverse apixaban in a rabbit model of bleeding and thrombosis.

Methods: After a dose-ranging study to assess the minimal amount of apixaban increasing bleeding, 63 anaesthetized rabbits were randomized into 5 groups: control (saline), apixaban (apixaban and saline), rFVIIa (apixaban and rFVIIa), PCC (apixaban and PCC) and fibrinogen (apixaban and Fib).

Mechanistic study of the proangiogenic effect of osteoprotegerin.

Osteoprotegerin (OPG), a soluble tumour necrosis factor receptor superfamily member, inhibits RANKL-mediated osteoclastogenesis. We have previously reported that OPG enhances the proangiogenic properties of endothelial colony-forming cells (ECFCs) in vitro, and promotes vasculogenesis in vivo. Here we investigated how OPG promotes neovascularisation.

A motif within the N-terminal domain of TSP-1 specifically promotes the proangiogenic activity of endothelial colony-forming cells.

Thrombospondin-1 (TSP-1) gives rise to fragments that have both pro- and anti-angiogenic effects in vitro and in vivo. The TSP-HepI peptide (2.3 kDa), located in the N-terminal domain of TSP-1, has proangiogenic effects on endothelial cells.

Tie2-dependent knockout of α6 integrin subunit in mice reduces post-ischaemic angiogenesis.

Aims: Integrins α6β1 and α6β4 are receptors for laminins, the main components of the basement membrane underlying the endothelial cells. In vitro, α6 integrin subunit (α6) expression at the surface of endothelial cells and their progenitors (EPCs) is up-regulated by pro-angiogenic growth factors and is crucial for adhesion, migration, and pseudotube formation. We investigated the role for α6 in post-ischaemic vascular repair in vivo.

Marine polysaccharides: a source of bioactive molecules for cell therapy and tissue engineering.

The therapeutic potential of natural bioactive compounds such as polysaccharides, especially glycosaminoglycans, is now well documented, and this activity combined with natural biodiversity will allow the development of a new generation of therapeutics. Advances in our understanding of the biosynthesis, structure and function of complex glycans from mammalian origin have shown the crucial role of this class of molecules to modulate disease processes and the importance of a deeper knowledge of structure-activity relationships. Marine environment offers a tremendous biodiversity and original polysaccharides have been discovered presenting a great chemical diversity that is largely species specific.

Evaluation of prothrombin complex concentrate and recombinant activated factor VII to reverse rivaroxaban in a rabbit model.

Background: As a potent anticoagulant agent, rivaroxaban exposes a risk of bleeding. An effective way to reverse its effects is needed. Objectives were to study efficacy and safety of recombinant activated factor VII (rFVIIa) and prothrombin complex concentrate (PCC) to reverse the anticoagulant effect of an overdose of rivaroxaban in a rabbit model of bleeding and thrombosis.

[Antiphospholipid syndrome diagnosis: an update].

The antiphospholipid syndrome (APS) is characterized by arterial and/or venous thrombosis and pregnancy morbidity in association with the persistent presence of autoantibodies called antiphospholipid antibodies (APAs). APAs are a heterogeneous group of circulating autoantibodies that can be detected either by phospholipid-dependent coagulation test for lupus anticoagulant (LA) or ELISA test for anticardiolipin and anti-β2GPI antibodies. In 2006, the revised criteria for the diagnosis of APS introduce the anti-β2GPI antibodies as a new biological criterion and highlight the necessity to increase the interval between two positive APA test from 6 to 12 weeks.

alpha6-integrin subunit plays a major role in the proangiogenic properties of endothelial progenitor cells.

Objective: Alpha6 integrin subunit (alpha6) expression is increased by proangiogenic growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor. This increase correlates with enhanced in vitro tube formation by endothelial cells and their progenitors called endothelial colony-forming cells (ECFCs). We thus studied the role of alpha6 in vasculogenesis induced by human ECFCs, in a mouse model of hindlimb ischemia.

Endothelial dysfunction in systemic lupus patients with low disease activity: evaluation by quantification and characterization of circulating endothelial microparticles, role of anti-endothelial cell antibodies.

Objective: We attempted to evaluate endothelial dysfunction and the role of AECAs in systemic lupus (SL) with low disease activity. We quantified endothelial microparticles (EMps) and attempted to find the best flow cytometry method for that purpose.

Methods: CD105, CD144 and CD146 were tested, individually or in combination, on EMp-enriched plasma.

Evaluation of hemostasis and endothelial function in patients with paroxysmal nocturnal hemoglobinuria receiving eculizumab.

Background: Paroxysmal nocturnal hemoglobinuria (PNH) is associated with an increased risk of thrombosis through unknown mechanisms.

Design And Methods: We studied 23 patients with PNH, before and after five and 11 weeks of treatment with eculizumab. We examined markers of thrombin generation and reactional fibrinolysis (prothrombin fragment 1+2 (F1+2), D-dimers, and plasmin antiplasmin complexes (P-AP), and endothelial dysfunction tissue plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1), soluble thrombomodulin (sTM), intercellular adhesion molecule 1 (sICAM-1), vascular cell adhesion molecule (sVCAM-1), endothelial microparticles (EMPs), and tissue factor pathway inhibitor (TFPI).