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1.
J Am Coll Health ; : 1-11, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652640

RESUMO

Objective: to examine factors associated with cigarette and hookah smoking among Middle Eastern (ME) Arab college women. Participants: 406 adult women of ME Arabic background, currently enrolled in or recently graduated from a US college. Methods: a cross-sectional design, using an anonymous online survey of demographic characteristics, sociocultural factors, and access to health care factors. Data analysis included regression model to identify predictors of smoking behaviors. Results: Smoking rates were 21% and 19% for cigarette and hookah smoking. Cigarette smoking was higher with having liberal attitudes toward sexuality and lower among those having a healthcare provider. Hookah smoking was higher among students who are Muslim, involved in student organizations, have higher acculturation-heritage levels, and have more liberal attitudes toward women. Hookah smoking was lower among students born in the US, attending college part-time, and having higher religiosity levels. Conclusions: The study findings have several implications for interventions to address smoking behaviors among ME Arab college women through community organizations and within college campuses.

2.
Eur Heart J ; 45(1): 18-31, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37940193

RESUMO

The leading cause of heart disease in developed countries is coronary atherosclerosis, which is not simply a result of ageing but a chronic inflammatory process that can lead to acute clinical events upon atherosclerotic plaque rupture or erosion and arterial thrombus formation. The composition and location of atherosclerotic plaques determine the phenotype of the lesion and whether it is more likely to rupture or to erode. Although plaque rupture and erosion both initiate platelet activation on the exposed vascular surface, the contribution of platelets to thrombus formation differs between the two phenotypes. In this review, plaque phenotype is discussed in relation to thrombus composition, and an overview of important mediators (haemodynamics, matrix components, and soluble factors) in plaque-induced platelet activation is given. As thrombus formation on disrupted plaques does not necessarily result in complete vessel occlusion, plaque healing can occur. Therefore, the latest findings on plaque healing and the potential role of platelets in this process are summarized. Finally, the clinical need for more effective antithrombotic agents is highlighted.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Trombose , Humanos , Placa Aterosclerótica/patologia , Doença da Artéria Coronariana/complicações , Plaquetas , Ruptura Espontânea/complicações , Trombose/etiologia , Biologia
3.
Nat Commun ; 14(1): 5585, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37696797

RESUMO

The success of the CD8 T cell-mediated immune response against infections and tumors depends on the formation of a long-lived memory pool, and the protection of effector cells from exhaustion. The advent of checkpoint blockade therapy has significantly improved anti-tumor therapeutic outcomes by reversing CD8 T cell exhaustion, but fails to generate effector cells with memory potential. Here, using in vivo mouse models, we show that let-7 miRNAs determine CD8 T cell fate, where maintenance of let-7 expression during early cell activation results in memory CD8 T cell formation and tumor clearance. Conversely, let-7-deficiency promotes the generation of a terminal effector population that becomes vulnerable to exhaustion and cell death in immunosuppressive environments and fails to reject tumors. Mechanistically, let-7 restrains metabolic changes that occur during T cell activation through the inhibition of the PI3K/AKT/mTOR signaling pathway and production of reactive oxygen species, potent drivers of terminal differentiation and exhaustion. Thus, our results reveal a role for let-7 in the time-sensitive support of memory formation and the protection of effector cells from exhaustion. Overall, our data suggest a strategy in developing next-generation immunotherapies by preserving the multipotency of effector cells rather than enhancing the efficacy of differentiation.


Assuntos
Linfócitos T CD8-Positivos , MicroRNAs , Fosfatidilinositol 3-Quinases , Animais , Camundongos , Anticorpos , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Neoplasias , Fosfatidilinositol 3-Quinases/genética , MicroRNAs/genética , MicroRNAs/metabolismo
4.
Circ Res ; 132(8): 970-992, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37053275

RESUMO

The endothelium is considered to be the gatekeeper of the vessel wall, maintaining and regulating vascular integrity. In patients with chronic kidney disease, protective endothelial cell functions are impaired due to the proinflammatory, prothrombotic and uremic environment caused by the decline in kidney function, adding to the increase in cardiovascular complications in this vulnerable patient population. In this review, we discuss endothelial cell functioning in healthy conditions and the contribution of endothelial cell dysfunction to cardiovascular disease. Further, we summarize the phenotypic changes of the endothelium in chronic kidney disease patients and the relation of endothelial cell dysfunction to cardiovascular risk in chronic kidney disease. We also review the mechanisms that underlie endothelial changes in chronic kidney disease and consider potential pharmacological interventions that can ameliorate endothelial health.


Assuntos
Doenças Cardiovasculares , Insuficiência Renal Crônica , Doenças Vasculares , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Endotélio Vascular/fisiologia , Fatores de Risco , Insuficiência Renal Crônica/complicações , Células Endoteliais , Fatores de Risco de Doenças Cardíacas
5.
Thromb Haemost ; 123(8): 808-839, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36913975

RESUMO

The Fourth Maastricht Consensus Conference on Thrombosis included the following themes. Theme 1: The "coagulome" as a critical driver of cardiovascular disease. Blood coagulation proteins also play divergent roles in biology and pathophysiology, related to specific organs, including brain, heart, bone marrow, and kidney. Four investigators shared their views on these organ-specific topics. Theme 2: Novel mechanisms of thrombosis. Mechanisms linking factor XII to fibrin, including their structural and physical properties, contribute to thrombosis, which is also affected by variation in microbiome status. Virus infection-associated coagulopathies perturb the hemostatic balance resulting in thrombosis and/or bleeding. Theme 3: How to limit bleeding risks: insights from translational studies. This theme included state-of-the-art methodology for exploring the contribution of genetic determinants of a bleeding diathesis; determination of polymorphisms in genes that control the rate of metabolism by the liver of P2Y12 inhibitors, to improve safety of antithrombotic therapy. Novel reversal agents for direct oral anticoagulants are discussed. Theme 4: Hemostasis in extracorporeal systems: the value and limitations of ex vivo models. Perfusion flow chamber and nanotechnology developments are developed for studying bleeding and thrombosis tendencies. Vascularized organoids are utilized for disease modeling and drug development studies. Strategies for tackling extracorporeal membrane oxygenation-associated coagulopathy are discussed. Theme 5: Clinical dilemmas in thrombosis and antithrombotic management. Plenary presentations addressed controversial areas, i.e., thrombophilia testing, thrombosis risk assessment in hemophilia, novel antiplatelet strategies, and clinically tested factor XI(a) inhibitors, both possibly with reduced bleeding risk. Finally, COVID-19-associated coagulopathy is revisited.


Assuntos
Transtornos da Coagulação Sanguínea , COVID-19 , Trombose , Humanos , Anticoagulantes/uso terapêutico , Coagulação Sanguínea , Hemostasia , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Hemorragia/tratamento farmacológico
6.
J Thromb Haemost ; 21(5): 1289-1306, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36754678

RESUMO

BACKGROUND: Especially in disease conditions, platelets can encounter activating agents in circulation. OBJECTIVES: To investigate the extent to which previously activated platelets can be reactivated and whether in-and reactivation applies to different aspects of platelet activation and thrombus formation. METHODS: Short-and long-term effects of glycoprotein VI (GPVI) and G protein-coupled receptor (GPCR) stimulation on platelet activation and aggregation potential were compared via flow cytometry and plate-based aggregation. Using fluorescence and electron microscopy, we assessed platelet morphology and content, as well as thrombus formation. RESULTS: After 30 minutes of stimulation with thrombin receptor activator peptide 6 (TRAP6) or adenosine diphosphate (ADP), platelets secondarily decreased in PAC-1 binding and were less able to aggregate. The reversibility of platelets after thrombin stimulation was concentration dependent. Reactivation was possible via another receptor. In contrast, cross-linked collagen-related peptide (CRP-XL) or high thrombin stimulation evoked persistent effects in αIIbß3 activation and platelet aggregation. However, after 60 minutes of CRP-XL or high thrombin stimulation, when αIIbß3 activation slightly decreased, restimulation with ADP or CRP-XL, respectively, increased integrin activation again. Compatible with decreased integrin activation, platelet morphology was reversed. Interestingly, reactivation of reversed platelets again resulted in shape change and if not fully degranulated, additional secretion. Moreover, platelets that were previously activated with TRAP6 or ADP regained their potential to contribute to thrombus formation under flow. On the contrary, prior platelet triggering with CRP-XL was accompanied by prolonged platelet activity, leading to a decreased secondary platelet adhesion under flow. CONCLUSION: This work emphasizes that prior platelet activation can be reversed, whereafter platelets can be reactivated through a different receptor. Reversed, previously activated platelets can contribute to thrombus formation.


Assuntos
Glicoproteínas da Membrana de Plaquetas , Trombose , Humanos , Glicoproteínas da Membrana de Plaquetas/metabolismo , Trombina/metabolismo , Ativação Plaquetária , Plaquetas/metabolismo , Agregação Plaquetária , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Trombose/metabolismo , Receptores de Trombina/metabolismo , Difosfato de Adenosina/farmacologia , Difosfato de Adenosina/metabolismo
8.
Int J Mol Sci ; 23(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36142125

RESUMO

Platelet and coagulation activation are highly reciprocal processes driven by multi-molecular interactions. Activated platelets secrete several coagulation factors and expose phosphatidylserine, which supports the activation of coagulation factor proteins. On the other hand, the coagulation cascade generates known ligands for platelet receptors, such as thrombin and fibrin. Coagulation factor (F)Xa, (F)XIIIa and activated protein C (APC) can also bind to platelets, but the functional consequences are unclear. Here, we investigated the effects of the activated (anti)coagulation factors on platelets, other than thrombin. Multicolor flow cytometry and aggregation experiments revealed that the 'supernatant of (hirudin-treated) coagulated plasma' (SCP) enhanced CRP-XL-induced platelet responses, i.e., integrin αIIbß3 activation, P-selectin exposure and aggregate formation. We demonstrated that FXIIIa in combination with APC enhanced platelet activation in solution, and separately immobilized FXIIIa and APC resulted in platelet spreading. Platelet activation by FXIIIa was inhibited by molecular blockade of glycoprotein VI (GPVI) or Syk kinase. In contrast, platelet spreading on immobilized APC was inhibited by PAR1 blockade. Immobilized, but not soluble, FXIIIa and APC also enhanced in vitro adhesion and aggregation under flow. In conclusion, in coagulation, factors other than thrombin or fibrin can induce platelet activation via GPVI and PAR receptors.


Assuntos
Selectina-P , Glicoproteínas da Membrana de Plaquetas , Plaquetas/metabolismo , Fator XIIIa/metabolismo , Fibrina/metabolismo , Hirudinas/metabolismo , Hirudinas/farmacologia , Selectina-P/metabolismo , Fosfatidilserinas/metabolismo , Ativação Plaquetária , Agregação Plaquetária , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Proteína C/metabolismo , Receptor PAR-1/metabolismo , Quinase Syk/metabolismo , Trombina/metabolismo , Trombina/farmacologia
9.
Herz ; 47(5): 426-433, 2022 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-35861809

RESUMO

Patients with chronic kidney disease (CKD) have an increased risk of thrombosis and approximately 50% of patients with advanced CKD die because of a cardiovascular disease. In addition to an increased risk of thrombosis, patients with CKD and particularly with advanced CKD, have an increased risk of hemorrhage, which increases parallel to the decline of kidney function. Due to this parallel existence of the prohemorrhagic and prothrombotic phenotype, antiplatelet treatment is difficult in the daily routine and data show that CKD patients with acute coronary syndrome (ACS) are less likely to receive guideline-conform treatment. The underlying mechanisms are currently insufficiently understood and both platelet-dependent mechanisms and also platelet-independent mechanisms are under discussion. Accordingly, there is currently no specific treatment or treatment strategy for patients with CKD. In addition, CKD patients are underrepresented in registration studies on antiplatelet treatment and there are no data from randomized trials for patients with advanced CKD (CKD ≥ 4). Current guideline recommendations are therefore based on subgroup analyses and observational studies. In addition, questions on the duration of treatment, on risk scores for estimation of the risk of hemorrhage and on potential benefits of escalation and de-escalation strategies remain largely unanswered and should therefore be the focus of future studies.


Assuntos
Diabetes Mellitus , Insuficiência Renal Crônica , Trombose , Hemorragia/induzido quimicamente , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico
10.
Biomedicines ; 10(5)2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35625720

RESUMO

Platelets are key regulators of haemostasis, making platelet dysfunction a major driver of thrombosis. Numerous processes that determine platelet function are influenced by microRNAs (miRs). MiR-26b is one of the highest-expressed miRs in healthy platelets, and its expression in platelets is changed in a diseased state. However, the exact effect of this miR on platelet function has not been studied yet. In this study, we made use of a whole-body knockout of miR-26b in ApoE-deficient mice in order to determine its impact on platelet function, thrombus formation and platelet signalling both ex vivo and in vivo. We show that a whole-body deficiency of miR-26b exacerbated platelet adhesion and aggregation ex vivo. Additionally, in vivo, platelets adhered faster, and larger thrombi were formed in mice lacking miR-26b. Moreover, isolated platelets from miR-26b-deficient mice showed a hyperactivated Src and EGFR signalling. Taken together, we show here for the first time that miR-26b attenuates platelet adhesion and aggregation, possibly through Src and EGFR signalling.

11.
Int J Mol Sci ; 23(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35008960

RESUMO

Patients with chronic kidney disease (CKD) are at a highly increased risk of cardiovascular complications, with increased vascular inflammation, accelerated atherogenesis and enhanced thrombotic risk. Considering the central role of the endothelium in protecting from atherogenesis and thrombosis, as well as its cardioprotective role in regulating vasorelaxation, this study aimed to systematically integrate literature on CKD-associated endothelial dysfunction, including the underlying molecular mechanisms, into a comprehensive overview. Therefore, we conducted a systematic review of literature describing uremic serum or uremic toxin-induced vascular dysfunction with a special focus on the endothelium. This revealed 39 studies analyzing the effects of uremic serum or the uremic toxins indoxyl sulfate, cyanate, modified LDL, the advanced glycation end products N-carboxymethyl-lysine and N-carboxyethyl-lysine, p-cresol and p-cresyl sulfate, phosphate, uric acid and asymmetric dimethylarginine. Most studies described an increase in inflammation, oxidative stress, leukocyte migration and adhesion, cell death and a thrombotic phenotype upon uremic conditions or uremic toxin treatment of endothelial cells. Cellular signaling pathways that were frequently activated included the ROS, MAPK/NF-κB, the Aryl-Hydrocarbon-Receptor and RAGE pathways. Overall, this review provides detailed insights into pathophysiological and molecular mechanisms underlying endothelial dysfunction in CKD. Targeting these pathways may provide new therapeutic strategies reducing increased the cardiovascular risk in CKD.


Assuntos
Suscetibilidade a Doenças , Células Endoteliais/metabolismo , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/metabolismo , Toxinas Urêmicas/efeitos adversos , Animais , Apoptose , Biomarcadores , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Estresse do Retículo Endoplasmático , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/metabolismo , Humanos , Óxido Nítrico/metabolismo , Estresse Oxidativo , Processamento de Proteína Pós-Traducional , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/terapia , Transdução de Sinais
12.
Thromb Haemost ; 122(5): 726-738, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34689320

RESUMO

Platelets from healthy donors display heterogeneity in responsiveness to agonists. The response thresholds of platelets are controlled by multiple bioactive molecules, acting as negatively or positively priming substances. Higher circulating levels of priming substances adenosine and succinate, as well as the occurrence of hypercoagulability, have been described for patients with ischaemic heart disease. Here, we present an improved methodology of flow cytometric analyses of platelet activation and the characterisation of platelet populations following activation and priming by automated clustering analysis.Platelets were treated with adenosine, succinate, or coagulated plasma before stimulation with CRP-XL, 2-MeSADP, or TRAP6 and labelled for activated integrin αIIbß3 (PAC1), CD62P, TLT1, CD63, and GPIX. The Super-Enhanced Dmax subtraction algorithm and 2% marker (quadrant) setting were applied to identify populations, which were further defined by state-of-the-art clustering techniques (tSNE, FlowSOM).Following activation, five platelet populations were identified: resting, aggregating (PAC1 + ), secreting (α- and dense-granules; CD62P + , TLT1 + , CD63 + ), aggregating plus α-granule secreting (PAC1 + , CD62P + , TLT1 + ), and fully active platelet populations. The type of agonist determined the distribution of platelet populations. Adenosine in a dose-dependent way suppressed the fraction of fully activated platelets (TRAP6 > 2-MeSADP > CRP-XL), whereas succinate and coagulated plasma increased this fraction (CRP-XL > TRAP6 > 2-MeSADP). Interestingly, a subset of platelets showed a constant response (aggregating, secreting, or aggregating plus α-granule secreting), which was hardly affected by the stimulus strength or priming substances.


Assuntos
Plaquetas , Ativação Plaquetária , Adenosina/farmacologia , Citometria de Fluxo/métodos , Humanos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas , Succinatos/farmacologia
13.
Clin J Am Soc Nephrol ; 17(1): 155-170, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34750169

RESUMO

Patients with CKD display a significantly higher risk of cardiovascular and thromboembolic complications, with around half of patients with advanced CKD ultimately dying of cardiovascular disease. Paradoxically, these patients also have a higher risk of hemorrhages, greatly complicating patient therapy. Platelets are central to hemostasis, and altered platelet function resulting in either platelet hyper- or hyporeactivity may contribute to thrombotic or hemorrhagic complications. Different molecular changes have been identified that may underlie altered platelet activity and hemostasis in CKD. In this study, we summarize the knowledge on CKD-induced aberrations in hemostasis, with a special focus on platelet abnormalities. We also discuss how prominent alterations in vascular integrity, coagulation, and red blood cell count in CKD may contribute to altered hemostasis in these patients who are high risk. Furthermore, with patients with CKD commonly receiving antiplatelet therapy to prevent secondary atherothrombotic complications, we discuss antiplatelet treatment strategies and their risk versus benefit in terms of thrombosis prevention, bleeding, and clinical outcome depending on CKD stage. This reveals a careful consideration of benefits versus risks of antiplatelet therapy in patients with CKD, balancing thrombotic versus bleeding risk. Nonetheless, despite antiplatelet therapy, patients with CKD remain at high cardiovascular risk. Thus, deep insights into altered platelet activity in CKD and underlying mechanisms are important for the optimization and development of current and novel antiplatelet treatment strategies, specifically tailored to these patients who are high risk. Ultimately, this review underlines the importance of a closer investigation of altered platelet function, hemostasis, and antiplatelet therapy in patients with CKD.


Assuntos
Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/etiologia , Plaquetas , Inibidores da Agregação Plaquetária/uso terapêutico , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/complicações , Plaquetas/patologia , Plaquetas/fisiologia , Humanos
14.
Thromb Haemost ; 122(1): 92-104, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34130349

RESUMO

BACKGROUND: Sunitinib is a multitarget tyrosine kinase inhibitor (TKI) used for cancer treatment. In platelets, sunitinib affects collagen-induced activation under noncoagulating conditions. We investigated (1) the effects of sunitinib on thrombus formation induced by other TK-dependent receptors, and (2) the effects under coagulating conditions. Cardiovascular disease is a comorbidity in cancer patients, resulting in possible aspirin treatment. Sunitinib and aspirin are associated with increased bleeding risk, and therefore we also investigated (3) the synergistic effects of these compounds on thrombus and fibrin formation. METHODS: Blood or isolated platelets from healthy volunteers or cancer patients were incubated with sunitinib and/or aspirin or vehicle. Platelet activation was determined by TK phosphorylation, flow cytometry, changes in [Ca2+]i, aggregometry, and whole blood perfusion over multiple surfaces, including collagen with(out) tissue factor (TF) was performed. RESULTS: Sunitinib reduced thrombus formation and phosphatidylserine (PS) exposure under flow on collagen type I and III. Also, sunitinib inhibited glycoprotein VI-induced TK phosphorylation and Ca2+ elevation. Upon TF-triggered coagulation, sunitinib decreased PS exposure and fibrin formation. In blood from cancer patients more pronounced effects of sunitinib were observed in lung and pancreatic as compared to neuroglioblastoma and other cancer types. Compared to sunitinib alone, sunitinib plus aspirin further reduced platelet aggregation, thrombus formation, and PS exposure on collagen under flow with(out) coagulation. CONCLUSION: Sunitinib suppresses collagen-induced procoagulant activity and delays fibrin formation, which was aggravated by aspirin. Therefore, we urge for awareness of the combined antiplatelet effects of TKIs with aspirin, as this may result in increased risk of bleeding.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Sunitinibe/farmacologia , Aspirina/metabolismo , Aspirina/farmacologia , Coagulação Sanguínea/fisiologia , Humanos , Agregação Plaquetária/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Sunitinibe/uso terapêutico , Trombose/tratamento farmacológico , Trombose/prevenção & controle
15.
Open Forum Infect Dis ; 8(8): ofab337, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34377727

RESUMO

Inpatient dialysis patients cannot isolate, resulting in a higher rate of coronavirus disease 2019 (COVID-19) infections, with increased severity and higher mortality rate [1]. We present 2 African American dialysis patients who developed severe COVID-19 infections after vaccination. Both patients had not mounted antibody response to the COVID-19 vaccine or to hepatitis B vaccination.

16.
Sci Rep ; 11(1): 12358, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117303

RESUMO

Novel platelet and megakaryocyte transcriptome analysis allows prediction of the full or theoretical proteome of a representative human platelet. Here, we integrated the established platelet proteomes from six cohorts of healthy subjects, encompassing 5.2 k proteins, with two novel genome-wide transcriptomes (57.8 k mRNAs). For 14.8 k protein-coding transcripts, we assigned the proteins to 21 UniProt-based classes, based on their preferential intracellular localization and presumed function. This classified transcriptome-proteome profile of platelets revealed: (i) Absence of 37.2 k genome-wide transcripts. (ii) High quantitative similarity of platelet and megakaryocyte transcriptomes (R = 0.75) for 14.8 k protein-coding genes, but not for 3.8 k RNA genes or 1.9 k pseudogenes (R = 0.43-0.54), suggesting redistribution of mRNAs upon platelet shedding from megakaryocytes. (iii) Copy numbers of 3.5 k proteins that were restricted in size by the corresponding transcript levels (iv) Near complete coverage of identified proteins in the relevant transcriptome (log2fpkm > 0.20) except for plasma-derived secretory proteins, pointing to adhesion and uptake of such proteins. (v) Underrepresentation in the identified proteome of nuclear-related, membrane and signaling proteins, as well proteins with low-level transcripts. We then constructed a prediction model, based on protein function, transcript level and (peri)nuclear localization, and calculated the achievable proteome at ~ 10 k proteins. Model validation identified 1.0 k additional proteins in the predicted classes. Network and database analysis revealed the presence of 2.4 k proteins with a possible role in thrombosis and hemostasis, and 138 proteins linked to platelet-related disorders. This genome-wide platelet transcriptome and (non)identified proteome database thus provides a scaffold for discovering the roles of unknown platelet proteins in health and disease.


Assuntos
Plaquetas/metabolismo , Doenças Hematológicas/genética , Megacariócitos/metabolismo , Proteoma/genética , Transcriptoma , Humanos , Anotação de Sequência Molecular , Proteoma/classificação , Proteoma/metabolismo
17.
J Am Soc Nephrol ; 32(7): 1583-1598, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33941607

RESUMO

BACKGROUND: Patients with CKD are at high risk for thrombotic and hemorrhagic complications. Abnormalities in platelet function are central to these complications, but reports on platelet function in relation to CKD are conflicting, and vary from decreased platelet reactivity to normal or increased platelet responsiveness. The direct effects of uremic toxins on platelet function have been described, with variable findings. METHODS: To help clarify how CKD affects platelet function, we conducted a systematic review and meta-analysis of platelet activity in CKD, with a focus on nondialysis-induced effects. We also performed an extensive literature search for the effects of individual uremic toxins on platelet function. RESULTS: We included 73 studies in the systematic review to assess CKD's overall effect on platelet function in patients; 11 of them described CKD's effect on ex vivo platelet aggregation and were included in the meta-analysis. Although findings on platelet abnormalities in CKD are inconsistent, bleeding time was mostly prolonged and platelet adhesion mainly reduced. Also, the meta-analysis revealed maximal platelet aggregation was significantly reduced in patients with CKD upon collagen stimulation. We also found that relatively few uremic toxins have been examined for direct effects on platelets ex vivo; ex vivo analyses had varying methods and results, revealing both platelet-stimulatory and inhibitory effects. However, eight of the 12 uremic toxins tested in animal models mostly induced prothrombotic effects. CONCLUSIONS: Overall, most studies report impaired function of platelets from patients with CKD. Still, a substantial number of studies find platelet function to be unchanged or even enhanced. Further investigation of platelet reactivity in CKD, especially during different CKD stages, is warranted.

18.
EJHaem ; 2(4): 685-699, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35845214

RESUMO

All irreversible Bruton tyrosine kinase (Btk) inhibitors including ibrutinib and acalabrutinib induce platelet dysfunction and increased bleeding risk. New reversible Btk inhibitors were developed, like MK-1026. The mechanism underlying increased bleeding tendency with Btk inhibitors remains unclear. We investigated the effects of ibrutinib, acalabrutinib and MK-1026 on platelet function in healthy volunteers, patients and Btk-deficient mice, together with off-target effects on tyrosine kinase phosphorylation. All inhibitors suppressed GPVI- and CLEC-2-mediated platelet aggregation, activation and secretion in a dose-dependent manner. Only ibrutinib inhibited thrombus formation on vWF-co-coated surfaces, while on collagen this was not affected. In blood from Btk-deficient mice, collagen-induced thrombus formation under flow was reduced, but preincubation with either inhibitor was without additional effects. MK-1026 showed less off-target effects upon GPVI-induced TK phosphorylation as compared to ibrutinib and acalabrutinib. In ibrutinib-treated patients, GPVI-stimulated platelet activation, and adhesion on vWF-co-coated surfaces were inhibited, while CLEC-2 stimulation induced variable responses. The dual inhibition of GPVI and CLEC-2 signalling by Btk inhibitors might account for the increased bleeding tendency, with ibrutinib causing more high-grade bleedings due to additional inhibition of platelet-vWF interaction. As MK-1026 showed less off-target effects and only affected activation of isolated platelets, it might be promising for future treatment.

19.
Eur Heart J Open ; 1(2): oeab017, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35919270

RESUMO

Aims: Vascular calcification is a hallmark of atherosclerotic burden and can predict the cardiovascular outcome. Vitamin K antagonists (VKA) are widely used anticoagulant drugs to treat patients at risk of arterial and venous thrombosis but are also associated with increase vascular calcification progression. We aim to unravel the paradox that VKA suppresses plasma coagulation but promotes vascular calcification and subsequent atherosclerosis-dependent coagulability of the vessel wall. Methods and results: Apoe -/- mice were placed on western-type diet enriched with the VKA warfarin for 18 weeks to measure atherosclerotic plaque burden, calcification, and coagulation. Patients (n = 54) displaying paroxysmal atrial fibrillation with a low cardiovascular risk, who were treated with VKA were included to measure pre-thrombotic state. Finally, primary vascular smooth muscle cells (VSMC) derived from human tissue explants were used for in vitro experiments. In Apoe -/- mice, VKA increases both atherosclerotic plaque size and calcification. Higher plaque calcification was associated with increased plasma levels of thrombin-antithrombin and factor IXa-antithrombin complexes in mice and patients treated with VKA. Mechanistically, phenotypic switching of VSMC into synthetic VSMC promotes thrombin generation, which is enhanced in a tissue-factor (TF)-dependent manner by VSMC calcification. Moreover, calcified VSMC exposed to whole blood under flow significantly enhanced platelet deposition and TF-dependent fibrin formation. Conclusions: Oral anticoagulation with VKA aggravates vascular calcification and atherosclerosis. VSMC phenotype differentiation impacts coagulation potential in a TF-dependent manner. VKA-induced vascular calcification increases hypercoagulability and could thereby potentially positively affect atherothrombosis.

20.
Respir Care ; 66(1): 156-169, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32962998

RESUMO

Management of patients with a tracheostomy tube includes many components of care provided by clinicians from various health care disciplines. In recent years, clinicians worldwide have demonstrated a renewed interest in the management of patients with tracheostomy due to the recognition that more effective and efficient management of this patient population is necessary to decrease morbidity and mortality and to optimize the value of the procedure. Commensurate with the goal of enhancing the care of patients with tracheostomy, we conducted a systematic review to facilitate the development of recommendations relevant to the care of adult patients with tracheostomy in the acute care setting. From our systematic review, clinical practice guidelines were developed to address questions regarding the impact of tracheostomy bundles, tracheostomy teams, and protocol-directed care on time to decannulation, length of stay, tracheostomy-related cost, tracheostomy-related adverse events, and other tracheostomy-related outcomes in tracheostomized adult patients in the acute care setting. Using a modification of the RAND/UCLA Appropriateness Method, 3 recommendations were developed to assist clinicians with tracheostomy management of adult patients in the acute care setting: (1) evidence supports the use of tracheostomy bundles that have been evaluated and approved by a team of individuals experienced in tracheostomy management to decrease time to decannulation, tracheostomy-related adverse events, and other tracheostomy-related outcomes, namely, improved tolerance of oral diet; (2) evidence supports the addition of a multidisciplinary tracheostomy team to improve time to decannulation, length of stay, tracheostomy-related adverse events, and other tracheostomy-related outcomes, namely, increased speaking valve use; (3) evidence supports the use of a weaning/decannulation protocol to guide weaning and removal of the tracheostomy tube to improve time to decannulation.


Assuntos
Cuidados Críticos , Traqueostomia , Adulto , Remoção de Dispositivo , Humanos , Revisões Sistemáticas como Assunto , Traqueostomia/efeitos adversos
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