LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 898

Search options

  1. Article ; Online: Acute Ischemic Stroke Thrombus Composition.

    Vandelanotte, Sarah / De Meyer, Simon F

    Neuroscience

    2024  

    Abstract: Ischemic stroke is caused by a thrombus blocking one or multiple arteries in the brain, resulting in irreversible damage in the associated brain tissue. The aim of therapy is to restore the blood flow as fast as possible. Two recanalization strategies ... ...

    Abstract Ischemic stroke is caused by a thrombus blocking one or multiple arteries in the brain, resulting in irreversible damage in the associated brain tissue. The aim of therapy is to restore the blood flow as fast as possible. Two recanalization strategies are currently available: pharmacological thrombolysis using recombinant tissue plasminogen activator (rt-PA) and mechanical removal of the thrombus. Despite recent advancements, achieving efficient recanalization remains a challenge. The precise causes of therapy failure are not fully understood but thrombus composition is likely a key factor in successful recanalization. This review explores acute ischemic stroke thrombus composition, its recently identified components, and how it affects stroke treatment. It also discusses how new insights could enhance current recanalization strategies for ischemic stroke patients.
    Language English
    Publishing date 2024-01-05
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 196739-3
    ISSN 1873-7544 ; 0306-4522
    ISSN (online) 1873-7544
    ISSN 0306-4522
    DOI 10.1016/j.neuroscience.2023.12.010
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: Platelet granules in vascular integrity.

    De Meyer, Simon F

    Blood

    2017  Volume 129, Issue 12, Page(s) 1573–1574

    MeSH term(s) Blood Platelets ; Cytoplasmic Granules ; Humans
    Language English
    Publishing date 2017-03-07
    Publishing country United States
    Document type Journal Article ; Comment
    ZDB-ID 80069-7
    ISSN 1528-0020 ; 0006-4971
    ISSN (online) 1528-0020
    ISSN 0006-4971
    DOI 10.1182/blood-2017-02-763540
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: Mechanical thrombectomy for acute ischemic stroke revealing a cardiac myxoma: histological and immunohistochemical study to determine myxomatous emboli.

    Vantyghem, Soetkin / Staessens, Senna / Francois, Olivier / De Meyer, Simon F / Vanacker, Peter

    Acta neurologica Belgica

    2023  Volume 123, Issue 3, Page(s) 1201–1203

    MeSH term(s) Humans ; Ischemic Stroke/complications ; Ischemic Stroke/diagnostic imaging ; Stroke/complications ; Stroke/diagnostic imaging ; Brain Ischemia/complications ; Brain Ischemia/diagnostic imaging ; Thrombectomy ; Myxoma/complications ; Myxoma/diagnostic imaging ; Myxoma/pathology ; Tissue Plasminogen Activator ; Treatment Outcome
    Chemical Substances Tissue Plasminogen Activator (EC 3.4.21.68)
    Language English
    Publishing date 2023-04-11
    Publishing country Italy
    Document type Letter
    ZDB-ID 127315-2
    ISSN 2240-2993 ; 0300-9009
    ISSN (online) 2240-2993
    ISSN 0300-9009
    DOI 10.1007/s13760-023-02254-6
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: Pretreatment with a dual antiplatelet and anticoagulant (APAC) reduces ischemia-reperfusion injury in a mouse model of temporary middle cerebral artery occlusion-implications for neurovascular procedures.

    Denorme, Frederik / Frösen, Juhana / Jouppila, Annukka / Lindgren, Antti / Resendiz-Nieves, Julio C / Manninen, Hannu / De Meyer, Simon F / Lassila, Riitta

    Acta neurochirurgica

    2024  Volume 166, Issue 1, Page(s) 137

    Abstract: Background: Several neurovascular procedures require temporary occlusion of cerebral arteries, leading to ischemia of unpredictable length, occasionally causing brain infarction. Experimental models of cerebral ischemia-reperfusion injury have ... ...

    Abstract Background: Several neurovascular procedures require temporary occlusion of cerebral arteries, leading to ischemia of unpredictable length, occasionally causing brain infarction. Experimental models of cerebral ischemia-reperfusion injury have established that platelet adhesion and coagulation play detrimental roles in reperfusion injury following transient cerebral ischemia. Therefore, in a model of cerebral ischemia-reperfusion injury (IRI), we investigated the therapeutic potential of a dual antiplatelet and anticoagulant (APAC) heparin proteoglycan mimetic which is able to bind to vascular injury sites.
    Methods: Brain ischemia was induced in mice by transient occlusion of the right middle cerebral artery for 60 min. APAC, unfractionated heparin (UFH) (both at heparin equivalent doses of 0.5 mg/kg), or vehicle was intravenously administered 10 min before or 60 min after the start of ischemia. At 24 h later, mice were scored for their neurological and motor behavior, and brain damage was quantified.
    Results: Both APAC and UFH administered before the onset of ischemia reduced brain injury. APAC and UFH pretreated mice had better neurological and motor functions (p < 0.05 and p < 0.01, respectively) and had significantly reduced cerebral infarct sizes (p < 0.01 and p < 0.001, respectively) at 24 h after transient occlusion compared with vehicle-treated mice. Importantly, no macroscopic bleeding complications were observed in either APAC- or UFH-treated animals. However, when APAC or UFH was administered 60 min after the start of ischemia, the therapeutic effect was lost, but without hemorrhaging either.
    Conclusions: Pretreatment with APAC or UFH was safe and effective in reducing brain injury in a model of cerebral ischemia induced by transient middle cerebral artery occlusion. Further studies on the use of APAC to limit ischemic injury during temporary occlusion in neurovascular procedures are indicated.
    MeSH term(s) Mice ; Animals ; Anticoagulants/pharmacology ; Anticoagulants/therapeutic use ; Infarction, Middle Cerebral Artery/drug therapy ; Brain/metabolism ; Heparin/pharmacology ; Heparin/therapeutic use ; Brain Ischemia/drug therapy ; Brain Ischemia/metabolism ; Reperfusion Injury/drug therapy ; Brain Injuries
    Chemical Substances Anticoagulants ; Heparin (9005-49-6)
    Language English
    Publishing date 2024-03-15
    Publishing country Austria
    Document type Journal Article
    ZDB-ID 80010-7
    ISSN 0942-0940 ; 0001-6268
    ISSN (online) 0942-0940
    ISSN 0001-6268
    DOI 10.1007/s00701-024-06017-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article ; Online: Thromboinflammation in Brain Ischemia: Recent Updates and Future Perspectives.

    De Meyer, Simon F / Langhauser, Friederike / Haupeltshofer, Steffen / Kleinschnitz, Christoph / Casas, Ana I

    Stroke

    2022  Volume 53, Issue 5, Page(s) 1487–1499

    Abstract: Despite decades of promising preclinical validation and clinical translation, ischemic stroke still remains as one of the leading causes of death and disability worldwide. Within its complex pathophysiological signatures, thrombosis and inflammation, ... ...

    Abstract Despite decades of promising preclinical validation and clinical translation, ischemic stroke still remains as one of the leading causes of death and disability worldwide. Within its complex pathophysiological signatures, thrombosis and inflammation, that is, thromboinflammation, are highly interconnected processes leading to cerebral vessel occlusion, inflammatory responses, and severe neuronal damage following the ischemic event. Hence, we here review the most recent updates on thromboinflammatory-dependent mediators relevant after stroke focusing on recent discoveries on platelet modulation, a potential regulation of the innate and adaptive immune system in thromboinflammation, utterly providing a thorough up-to-date overview of all therapeutic approaches currently undergoing clinical trial.
    MeSH term(s) Brain Ischemia/drug therapy ; Humans ; Inflammation ; Stroke/drug therapy ; Thromboinflammation ; Thrombosis
    Language English
    Publishing date 2022-04-01
    Publishing country United States
    Document type Journal Article ; Review ; Research Support, Non-U.S. Gov't
    ZDB-ID 80381-9
    ISSN 1524-4628 ; 0039-2499 ; 0749-7954
    ISSN (online) 1524-4628
    ISSN 0039-2499 ; 0749-7954
    DOI 10.1161/STROKEAHA.122.038733
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article ; Online: Thrombus heterogeneity in ischemic stroke.

    Staessens, Senna / De Meyer, Simon F

    Platelets

    2020  Volume 32, Issue 3, Page(s) 331–339

    Abstract: The structure of stroke thrombi has gained an increasing amount of interest in recent years. The advent of endovascular thrombectomy has offered the unique opportunity to provide and analyze thrombi removed from ischemic stroke patients. It has become ... ...

    Abstract The structure of stroke thrombi has gained an increasing amount of interest in recent years. The advent of endovascular thrombectomy has offered the unique opportunity to provide and analyze thrombi removed from ischemic stroke patients. It has become clear that the composition of ischemic stroke thrombi is relatively heterogenous and various molecular and cellular patterns become apparent. Good understanding of the histopathologic characteristics of thrombi is important to lead future advancements in acute ischemic stroke treatment. In this review, we give a brief overview of the main stroke thrombus components that have been recently characterized in this rapidly evolving field. We also summarize how thrombus heterogeneity can affect stroke treatment.
    MeSH term(s) Female ; Genetic Heterogeneity ; Humans ; Ischemic Stroke/complications ; Ischemic Stroke/genetics ; Ischemic Stroke/pathology ; Male ; Thrombectomy/methods ; Thrombosis/genetics
    Language English
    Publishing date 2020-04-20
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 1034283-7
    ISSN 1369-1635 ; 0953-7104
    ISSN (online) 1369-1635
    ISSN 0953-7104
    DOI 10.1080/09537104.2020.1748586
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article ; Online: Toward gene therapy for congenital thrombotic thrombocytopenic purpura.

    Dekimpe, Charlotte / Roose, Elien / Sakai, Kazuya / Tersteeg, Claudia / De Meyer, Simon F / Vanhoorelbeke, Karen

    Journal of thrombosis and haemostasis : JTH

    2022  Volume 21, Issue 5, Page(s) 1090–1099

    Abstract: Congenital thrombotic thrombocytopenic purpura (cTTP) is caused by a severe deficiency in the plasma metalloprotease ADAMTS-13. The current management of cTTP is dependent on the prophylactic administration of ADAMTS-13 via plasma infusion. This is a ... ...

    Abstract Congenital thrombotic thrombocytopenic purpura (cTTP) is caused by a severe deficiency in the plasma metalloprotease ADAMTS-13. The current management of cTTP is dependent on the prophylactic administration of ADAMTS-13 via plasma infusion. This is a demanding therapy for patients because transfusions are lifelong and time-consuming and allergic reactions frequently occur. Although current management of cTTP controls acute episodes, it does not provide a long-lasting cure for this disease. The endogenous expression of ADAMTS-13 after gene transfer would provide a curative therapy and ongoing research explores various preclinical gene therapeutic approaches for cTTP. This review focuses on the current state of the literature regarding preclinical gene therapy studies for cTTP and on the challenges of developing a gene therapy medicinal product for cTTP.
    MeSH term(s) Humans ; Purpura, Thrombotic Thrombocytopenic/genetics ; Purpura, Thrombotic Thrombocytopenic/therapy ; ADAMTS13 Protein ; Plasma ; Blood Transfusion ; Genetic Therapy/adverse effects
    Chemical Substances ADAMTS13 Protein (EC 3.4.24.87)
    Language English
    Publishing date 2022-12-27
    Publishing country England
    Document type Journal Article ; Review ; Research Support, Non-U.S. Gov't
    ZDB-ID 2112661-6
    ISSN 1538-7836 ; 1538-7933
    ISSN (online) 1538-7836
    ISSN 1538-7933
    DOI 10.1016/j.jtha.2022.12.018
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  8. Article ; Online: Spatiotemporal profile of neutrophil extracellular trap formation in a mouse model of ischemic stroke.

    De Wilde, Maaike / Desender, Linda / Tersteeg, Claudia / Vanhoorelbeke, Karen / De Meyer, Simon F

    Research and practice in thrombosis and haemostasis

    2022  Volume 7, Issue 1, Page(s) 100028

    Abstract: Background: Thromboinflammatory processes modulate the complex pathophysiology of cerebral ischemia-reperfusion (I/R) injury in ischemic stroke, but the exact underlying mechanisms remain poorly understood. Emerging evidence indicates that neutrophil ... ...

    Abstract Background: Thromboinflammatory processes modulate the complex pathophysiology of cerebral ischemia-reperfusion (I/R) injury in ischemic stroke, but the exact underlying mechanisms remain poorly understood. Emerging evidence indicates that neutrophil extracellular traps (NETs) might play an important role in the thromboinflammatory cascade. In addition, the link between von Willebrand factor (VWF) and neutrophil recruitment in the ischemic brain might promote thromboinflammation, possibly by the formation of NETs.
    Objectives: To study NET formation in a murine model of cerebral I/R injury in ischemic stroke.
    Methods: The filament-induced transient middle cerebral artery occlusion model was used to induce 60 minutes of focal cerebral ischemia after which reperfusion was allowed. At different time points postischemia, NETs were identified in the ischemic mouse brain using quantitative immunofluorescence microscopy.
    Results: NETs could be identified in the ipsilateral brain hemisphere. Interestingly, NETs could already be detected at 6 hours poststroke. Their presence increased at 12 hours, was highest at 24 hours, and decreased again 48 hours postischemia. Remarkably, NETs were predominantly localized within the brain vasculature postischemia, suggesting that NETs play a role in secondary microthrombosis. Strikingly, NET formation was significantly decreased in VWF-deficient mice compared to littermate wild-type mice 24 hours postischemia, indicating a possible role for VWF in promoting NETosis in the ischemic brain.
    Conclusion: This study identified the spatiotemporal profile of NET formation in a mouse model of cerebral I/R injury in ischemic stroke. NETs, potentially in combination with VWF, might be attractive targets for the development of novel therapeutic strategies in ischemic stroke treatment.
    Language English
    Publishing date 2022-12-23
    Publishing country United States
    Document type Journal Article
    ISSN 2475-0379
    ISSN (online) 2475-0379
    DOI 10.1016/j.rpth.2022.100028
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  9. Article ; Online: R-tPA Resistance Is Specific for Platelet-Rich Stroke Thrombi and Can Be Overcome by Targeting Nonfibrin Components.

    Vandelanotte, Sarah / François, Olivier / Desender, Linda / Staessens, Senna / Vanhoorne, Alexander / Van Gool, Fréderick / Tersteeg, Claudia / Vanhoorelbeke, Karen / Vanacker, Peter / Andersson, Tommy / De Meyer, Simon F

    Stroke

    2024  Volume 55, Issue 5, Page(s) 1181–1190

    Abstract: Background: Resistance to r-tPA (recombinant tissue-type plasminogen activator) is a well-known but poorly understood phenomenon that hampers successful recanalization in patients with acute ischemic stroke. Using clinically relevant thrombi from ... ...

    Abstract Background: Resistance to r-tPA (recombinant tissue-type plasminogen activator) is a well-known but poorly understood phenomenon that hampers successful recanalization in patients with acute ischemic stroke. Using clinically relevant thrombi from patients with acute ischemic stroke, we investigated if and how thrombus composition impacts r-tPA-mediated lysis. In addition, we explored strategies to overcome r-tPA resistance.
    Methods: Thrombi were split into 2 parts, 1 of which was used for thrombolysis and the other for detailed histological analysis. Thrombolysis was performed in normal human plasma using r-tPA alone, using r-tPA in combination with DNase-1 or using r-tPA in combination with N,N'-diacetyl-l-cystine. Thrombus lysis was calculated as the percentage of residual thrombus weight compared with its initial weight and the degree of lysis was linked to thrombus composition determined via histology.
    Results: Interestingly, we found that the efficacy of r-tPA-mediated thrombolysis was strongly correlated with the composition of the thrombi. Thrombi containing high amounts of red blood cells and low amounts of DNA and von Willebrand Factor were efficiently degraded by r-tPA, whereas thrombi containing low amounts of red blood cells and higher amounts of DNA and von Willebrand Factor were resistant to r-tPA. Importantly, combination of r-tPA with DNase-1 or N,N'-diacetyl-l-cystine significantly and specifically improved the lysis of these r-tPA-resistant thrombi.
    Conclusions: Using patient thrombus material, our results for the first time show that the composition of stroke thrombi largely determines their susceptibility to r-tPA-mediated thrombolysis. Red blood cell-poor thrombi have a specific resistance to r-tPA, which can be overcome by targeting nonfibrin components using DNase-1 or N,N'-diacetyl-l-cystine.
    Language English
    Publishing date 2024-03-25
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80381-9
    ISSN 1524-4628 ; 0039-2499 ; 0749-7954
    ISSN (online) 1524-4628
    ISSN 0039-2499 ; 0749-7954
    DOI 10.1161/STROKEAHA.123.045880
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  10. Article ; Online: Diagnosis of thrombotic thrombocytopenic purpura: Easy-to-use fiber-optic surface plasmon resonance immunoassays for automated ADAMTS13 antigen and conformation evaluation.

    Bonnez, Quintijn / Dekimpe, Charlotte / Bekaert, Tim / Tellier, Edwige / Kaplanski, Gilles / Joly, Bérangère S / Veyradier, Agnès / Coppo, Paul / Lammertyn, Jeroen / Tersteeg, Claudia / De Meyer, Simon F / Vanhoorelbeke, Karen

    Journal of thrombosis and haemostasis : JTH

    2024  

    Abstract: Background: Laboratory diagnosis of immune-mediated thrombotic thrombocytopenic purpura (iTTP) remains challenging when ADAMTS13 activity ranges between 10-20%. To prevent misdiagnosis, open ADAMTS13 conformation gained clinical attention as a novel ... ...

    Abstract Background: Laboratory diagnosis of immune-mediated thrombotic thrombocytopenic purpura (iTTP) remains challenging when ADAMTS13 activity ranges between 10-20%. To prevent misdiagnosis, open ADAMTS13 conformation gained clinical attention as a novel biomarker especially to diagnose acute iTTP in patient with diagnostic undecisive ADAMTS13 activity. Plasma ADAMTS13 conformation analysis corrects for ADAMTS13 antigen with both parameters being characterized in enzyme-linked immunosorbent assay (ELISA)-based reference assays requiring expert technicians.
    Objectives: To design ADAMTS13 antigen and conformation assays on automated, easy-to-use fiber-optic surface plasmon resonance (FO-SPR) technology to promote assay accessibility and diagnose challenging iTTP patients.
    Patients/methods: ADAMTS13 antigen and conformation assays were designed on FO-SPR technology. Plasma of twenty healthy donors and twenty acute iTTP patients were quantified and data from FO-SPR and ELISA reference assays were compared.
    Results: Following assay design, both antigen and conformation FO-SPR assays were optimized and characterized presenting strong analytical sensitivity (detection limit of 0.001 μg/mL) and repeatability (inter-assay variation of 14.4%). Comparative analysis suggests positive correlation (Spearman r of 0.92) and good agreement between FO-SPR and ELISA assays. As expected, FO-SPR assays showed a closed or open ADAMTS13 conformation in healthy donors and acute iTTP patients respectively.
    Conclusions: Both ADAMTS13 antigen and conformation assays were transferred onto automated, easy-to-use FO-SPR technology displaying potent analytical sensitivity and reproducibility. ADAMTS13 antigen and conformation were determined for healthy donors and acute iTTP patients showing strong correlation with ELISA reference. Introducing FO-SPR technology in clinical context could support routine diagnosis of acute iTTP patients, notably when ADAMTS13 activity fluctuates between 10-20%.
    Language English
    Publishing date 2024-03-28
    Publishing country England
    Document type Journal Article
    ZDB-ID 2112661-6
    ISSN 1538-7836 ; 1538-7933
    ISSN (online) 1538-7836
    ISSN 1538-7933
    DOI 10.1016/j.jtha.2024.03.012
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top