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1.
Ann Chir Plast Esthet ; 68(2): 152-161, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35987670

RESUMO

BACKGROUND: Combining fat graft with platelet derived products is now common practice in regenerative surgery. We proposed to assess the safety and efficacy of Platelet-Rich Plasma (PRP) addition to a micro-lipofilling protocol for facial treatment of patients suffering from Systemic Sclerosis (SSc). OBJECTIVE: Main objective was to evaluate the improvement of the Mouth Handicap In Systemic Sclerosis (MHISS) scale score at 6 months post-therapy. METHOD: Included SSc patients had a MHISS score equal or up to 20. Surgery was performed under general anesthesia. Micro-fat and PRP (CCA-NA from DEPA Classification) were mixed in a 70/30 ratio, before injection in peri-oral sites according to a specific protocol. Efficacy criteria were recorded at baseline, 3 and 6 months. Moreover, we compared this cohort (current study) to a former (2015) non-enriched micro-lipofilling cohort in the same indication, using the same protocol. RESULTS: Thirteen women patients with mean age of 53.2 years (±14.3) have been included. At baseline, mean MHISS score was 29.5 (±8.7) and significantly decreased to 22.5 (±7.8) at 6 months (P=0.016), corresponding to a 22.0% of improvement from baseline, with a mean decrease of 6.5 points (±7.5) at 6 months. Patients received a mean volume of 30.8ml PRP-micro-fat (±8.1ml). CONCLUSION: PRP addition appeared beneficial, however, controlled studies are required to determine its superiority to facial micro-lipofilling.


Assuntos
Plasma Rico em Plaquetas , Escleroderma Sistêmico , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Escleroderma Sistêmico/cirurgia , Face/cirurgia , Boca , Resultado do Tratamento
2.
Cytometry A ; 89(2): 148-58, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25963580

RESUMO

Clinical determination of MP counts using flow cytometry has not been fully accepted yet due to the lack of standardization protocols. In the past 5 years, we have proposed two versions of a method with reproducible PMP counts in plasma samples. Both methods use forward scatter (FSC)-based threshold set with reference beads of appropriate sizes; first using 0.5 µm beads and later with 0.3 µm beads. Both systems provide reproducible PMP counts. However, this technique works only with some of currently used commercial flow cytometers. Instruments with limited resolution or generating heterogeneous FSC signals are excluded. Such performances are incompatible with the required interinstrument standardization. Here we show that (i) flow cytometers with sub-optimal FSC capabilities generally have higher SSC resolution and background rejection capacity, and (ii) that the same biological entities, "dim and bright PMP," both can be counted using alternative strategies, either as previously described, based on FSC measurements, or as presented here, based on SSC detection. The critical element in the standardization protocol is the use of different sizes of reference beads. This study was designed to permit simultaneous access to both FSC- and SSC-optimized platforms. A new range of about 0.17-0.6 µm eq. (µm-equivalents) is proposed for an alternative SSC-based MP gate generating the same PMP counts as those obtained in the previously proposed 0.3-1 µm eq. FSC-based MP gate. The two equivalent standardization options reconcile intrinsically different scattering behaviors between SSC- and FCS--triggered instruments and open the opportunity for multicenter studies in the future.


Assuntos
Micropartículas Derivadas de Células/fisiologia , Citometria de Fluxo/métodos , Plaquetas/fisiologia , Citometria de Fluxo/normas , Humanos , Luz , Contagem de Plaquetas , Padrões de Referência , Espalhamento de Radiação
3.
Pathol Biol (Paris) ; 62(1): 1-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24485849

RESUMO

Thrombosis is one of the major causes of human death worldwide. Identification of the cellular and molecular mechanisms leading to thrombus formation is thus crucial for the understanding of the thrombotic process. To examine thrombus formation in a living mouse, new technologies have been developed. Digital intravital microscopy allows to visualize the development of thrombosis and generation of fibrin in real-time within living animal in a physiological context. This specific system allowed the identification of new cellular partners involved in platelet adhesion and activation. Furthermore, it improved, especially, the knowledge of the early phase of thrombus formation and fibrin generation in vivo. Until now, platelets used to be considered the sole central player in thrombus generation. However, recently, it has been demonstrated that leukocytes, particularly neutrophils, play a crucial role in the activation of the blood coagulation cascade leading to thrombosis. In this review, we summarized the mechanisms leading to thrombus formation in the microcirculation according to the method of injury in mice with a special focus on the new identified roles of neutrophils in this process.


Assuntos
Neutrófilos/fisiologia , Trombose/fisiopatologia , Animais , Artérias/lesões , Proteínas Sanguíneas/fisiologia , Cloretos/toxicidade , Sistemas Computacionais , Grânulos Citoplasmáticos/metabolismo , Modelos Animais de Doenças , Endotélio Vascular/lesões , Endotélio Vascular/fisiopatologia , Matriz Extracelular/fisiologia , Compostos Férricos/toxicidade , Lasers/efeitos adversos , Camundongos , Microcirculação , Infiltração de Neutrófilos , Neutrófilos/ultraestrutura , Ativação Plaquetária , Tromboplastina/metabolismo , Trombose/sangue , Trombose/induzido quimicamente , Trombose/etiologia
4.
Eur J Vasc Endovasc Surg ; 43(2): 154-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22075154

RESUMO

OBJECTIVE: To test plasma levels of lipoprotein-associated phospholipase A2 (Lp-PLA2) in patients with high-grade carotid stenosis according to plaque histology. METHODS: This cross-sectional single-centre study included patients with ≥70% North American Symptomatic Carotid Endarterectomy Trial (NASCET) carotid stenosis, who were treated surgically. Serum Lp-PLA2 and high-sensitivity C-reactive protein (hs-CRP) were determined on the day of surgery. Histopathological analysis classified carotid plaque as stable or unstable, according to AHA classification. RESULTS: Of the 42 patients (mean age 70.4 ± 10.5 years; 67% men), neurological symptoms were present in 16 (38%). Unstable plaques were found in 23 (55%). Median plasma level of Lp-PLA2 was significantly higher in patients with unstable plaque compared to those with stable plaque (222.4 (174.9-437.5) interquartile range (IQR) 63.5 vs. 211.1 (174.9-270.6) IQR 37.2 ng ml(-1); p = 0.02). Moreover, median Lp-PLA2 level were higher in asymptomatic patients with unstable plaque (226.8 ng ml(-1) (174.9-437.5) IQR 76.8) vs. stable plaque (206.9 ng ml(-1) (174.9-270.6) IQR 33.7; p = 0.16). Logistic regression showed that only the neurological symptoms (OR = 30.9 (3.7-244.6); p < 0.001) and the plasma Lp-PLA2 level (OR = 1.7 (1.1-12.3); p = 0.03) were independently associated with unstable carotid plaque as defined by histology. CONCLUSIONS: This study showed that circulating Lp-PLA2 was increased in patients with high-grade carotid stenosis and unstable plaque. Lp-PLA2 may be a relevant biomarker to guide for invasive therapy in asymptomatic patients with carotid artery disease.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/sangue , Biomarcadores/sangue , Estenose das Carótidas/enzimologia , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/metabolismo , Estudos Transversais , Endarterectomia das Carótidas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/complicações , Estudos Prospectivos
5.
Int J Obes (Lond) ; 35(12): 1479-86, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21386797

RESUMO

BACKGROUND: In obesity, metabolic stress and inflammation in injured tissues could favour enhanced shedding of procoagulant microparticles (MPs). At sites of endothelium injury, the swift recruitment of procoagulant leukocyte-derived MPs enables the initiation of blood coagulation and thrombus growth. OBJECTIVES: In obese females, we sought to evaluate the impact of a very low-calorie diet (VLCD) on procoagulant MP levels, fibrinolytic status, inflammation and endothelium damage. METHODS: Circulating biomarkers of vascular damage, fibrinolytic status, platelet activation and inflammation were measured before, 30 and 90 days after starting a short-term VLCD. MPs were measured by flow cytometry and capture assays. Their procoagulant potential was quantified using functional prothrombinase assays and their cellular origin were determined using flow cytometry (endothelium, platelet, leukocyte, lymphocyte and erythrocyte-derived MP) or capture assays. RESULTS: A total of 24 obese females (39 ± 10 years) with a mean body mass index of 35 ± 4 kg m(-2) were prospectively enroled. Procoagulant leukocyte-derived MPs were associated with the waist circumference at baseline (r=0.534; P=0.010) and at 90 days follow-up (r=0.487; P=0.021). At 90 days, weight reduction (-9.8%) was associated with a lowering of blood pressure, improvement of metabolic parameters and a significant reduction of plasminogen activator inhibitor-1 (PAI-1) (-38%), procoagulant platelet-derived MPs (-43%), leukocyte-derived MPs (-28%) and leptin (-32%) levels. CONCLUSION: In obese females, a short-term VLCD results in an overall improvement of the haemostatic balance characterized by the reduction of PAI-levels, diminished release of platelet and leukocyte-derived MPs and a reduction in leptin levels, an adipocyte-derived cytokine.


Assuntos
Fatores de Coagulação Sanguínea/metabolismo , Plaquetas/metabolismo , Restrição Calórica , Leptina/sangue , Leptina/metabolismo , Leucócitos/metabolismo , Obesidade/sangue , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Endotélio Vascular/metabolismo , Eritrócitos/metabolismo , Feminino , Hemostasia , Humanos , Pessoa de Meia-Idade , Obesidade/dietoterapia , Obesidade/metabolismo , Estudos Prospectivos , Tromboplastina/metabolismo , Trombose/metabolismo , Redução de Peso , Adulto Jovem
6.
Nutr Metab Cardiovasc Dis ; 21(9): 665-71, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20399083

RESUMO

BACKGROUND AND AIMS: The Metabolic Syndrome (MetS) is associated with increased cardiovascular risk. Circulating microparticles (MP) are involved in the pathogenesis of atherothrombotic disorders and are raised in individual with CVD. We measured their level and cellular origin in subjects with MetS and analyzed their associations with 1/anthropometric and biological parameters of MetS, 2/inflammation and oxidative stress markers. METHODS AND RESULTS: Eighty-eight subjects with the MetS according to the NCEP-ATPIII definition were enrolled in a bicentric study and compared to 27 healthy controls. AnnexinV-positive MP (TMP), MP derived from platelets (PMP), erythrocytes (ErMP), endothelial cells (EMP), leukocytes (LMP) and granulocytes (PNMP) were determined by flow cytometry. MetS subjects had significantly higher counts/µl of TMP (730.6±49.7 vs 352.8±35.6), PMP (416.0±43.8 vs 250.5±23.5), ErMP (243.8±22.1 vs 73.6±19.6) and EMP (7.8±0.8 vs 4.0±1.0) compared with controls. LMP and PNMP were not statistically different between groups. Multivariate analysis demonstrated that each criterion for the MetS influenced the number of TMP. Waist girth was a significant determinant of PMP and EMP level and blood pressure was correlated with EMP level. Glycemia positively correlated with PMP level whereas dyslipidemia influenced EMP and ErMP levels. Interestingly, the oxidative stress markers, plasma glutathione peroxydase and urinary 8-iso-prostaglandin F(2) α, independently influenced TMP and PMP levels whereas inflammatory markers did not, irrespective of MP type. CONCLUSION: Increased levels of TMP, PMP, ErMP and EMP are associated with individual metabolic abnormalities of MetS and oxidative stress. Whether MP assessment may represent a marker for risk stratification or a target for pharmacological intervention deserves further investigation.


Assuntos
Plaquetas/patologia , Micropartículas Derivadas de Células/metabolismo , Células Endoteliais/patologia , Eritrócitos/metabolismo , Síndrome Metabólica/patologia , Estresse Oxidativo , Adulto , Idoso , Biomarcadores/sangue , Plaquetas/metabolismo , Estudos de Casos e Controles , Micropartículas Derivadas de Células/patologia , Células Endoteliais/metabolismo , Feminino , Citometria de Fluxo , Humanos , Interleucina-6/sangue , Modelos Lineares , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/sangue , Molécula 1 de Adesão de Célula Vascular/sangue
7.
Sci Rep ; 10(1): 4147, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32139753

RESUMO

Developing targeted nanoparticles is a rising strategy to improve drug delivery in oncology. Antibodies are the most commonly used targeting agents. However, determination of their optimal number at the surface remains a challenging issue, mainly due to the difficulties in measuring precisely surface coating levels when prototyping nanoparticles. We developed an original quantitative assay to measure the exact number of coated antibodies per nanoparticle. Using flow cytometry optimized for submicron particle analysis and beads covered with known amounts of human IgG-kappa mimicking various amounts of antibodies, this new method was tested as part of the prototyping of docetaxel liposomes coated with trastuzumab against Her2+ breast cancer. This quantification method allowed to discriminate various batches of immunoliposomes depending on their trastuzumab density on nanoparticle surface (i.e., 330 (Immunoliposome-1), 480 (Immunoliposome-2) and 690 (Immunoliposome-3), p = 0.004, One-way ANOVA). Here we showed that optimal number of grafted antibodies on nanoparticles should be finely tuned and highest density of targeting agent is not necessarily associated with highest efficacy. Overall, this new method should help to better prototype third generation nanoparticles.


Assuntos
Docetaxel/química , Lipossomos/química , Trastuzumab/química , Análise de Variância , Citometria de Fluxo , Nanopartículas/química
8.
J Cell Mol Med ; 13(3): 454-71, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19379144

RESUMO

The balance between lesion and regeneration of the endothelium is critical for the maintenance of vessel integrity. Exposure to cardiovascular risk factors (CRF) alters the regulatory functions of the endothelium that progresses from a quiescent state to activation, apoptosis and death. In the last 10 years, identification of circulating endothelial cells (CEC) and endothelial-derived microparticles (EMP) in the circulation has raised considerable interest as non-invasive markers of vascular dysfunction. Indeed, these endothelial-derived biomarkers were associated with most of the CRFs, were indicative of a poor clinical outcome in atherothrombotic disorders and correlated with established parameters of endothelial dysfunction. CEC and EMP also behave as potential pathogenic vectors able to accelerate endothelial dysfunction and promote disease progression. The endothelial response to injury has been enlarged by the discovery of a powerful physiological repair process based on the recruitment of circulating endothelial progenitor cells (EPC) from the bone marrow. Recent studies indicate that reduction of EPC number and function by CRF plays a critical role in the progression of cardiovascular diseases. This EPC-mediated repair to injury response can be integrated into a clinical endothelial phenotype defining the 'vascular competence' of each individual. In the future, provided that standardization of available methodologies could be achieved, multimarker strategies combining CEC, EMP and EPC levels as integrative markers of 'vascular competence' may offer new perspectives to assess vascular risk and to monitor treatment efficacy.


Assuntos
Vasos Sanguíneos/fisiologia , Micropartículas Derivadas de Células/metabolismo , Células Endoteliais/metabolismo , Células-Tronco/metabolismo , Animais , Células Endoteliais/patologia , Humanos , Regeneração , Cicatrização
9.
Am J Transplant ; 9(3): 550-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19260834

RESUMO

Microparticles (MP) are important players in cardiovascular disorders. Renal transplantation significantly improves the survival of hemodialyzed patients, in part because cardiovascular disease (CVD) progression is lessened. We hypothesized that the beneficial effect of renal transplantation on cardiovascular outcome might involve decreased levels of circulating MP. We evaluated the kinetics of MP subpopulations and their procoagulant activity (MP-PCA) in 52 patients before and 3, 6, 9 and 12 months after graft with reference to 50 healthy controls and we evaluated the impact of cardiovascular complications. During the follow-up, the increased levels of MP observed before graft were significantly decreased and reached normal values with different kinetics according to their cellular origin whereas MP-PCA remained significantly higher than in controls. From multivariate analysis, the levels of MP were negatively correlated with renal function. At 12 months, the decrease in MP and MP-PCA was more pronounced in patients without history of CVD than those with. In conclusion, we demonstrated that renal graft is associated with decreased levels of MP levels and MP-PCA, even more pronounced so in patients without history of CVD. Therefore, we suggest that MP lowering could be involved in the vascular dysfunction improvements reported after transplantation.


Assuntos
Coagulação Sanguínea , Micropartículas Derivadas de Células/metabolismo , Transplante de Rim , Coagulação Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/metabolismo , Micropartículas Derivadas de Células/efeitos dos fármacos , Micropartículas Derivadas de Células/imunologia , Feminino , Sobrevivência de Enxerto , Doença Enxerto-Hospedeiro/imunologia , Humanos , Imunossupressores/farmacologia , Transplante de Rim/imunologia , Cinética , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
10.
Am J Transplant ; 8(11): 2360-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18925903

RESUMO

Endothelial dysfunction occurs in hemodialysis and kidney-transplanted patients and can be enhanced by immunosuppressive therapy. Circulating endothelial cells (CEC), endothelial microparticles (EMP) and sVCAM-1 provide information on endothelium activation and damage. We compared the impact of two immunosuppressive regimens (CsA/Aza vs. Tac/MMF) on the kinetics of CEC, EMP and sVCAM-1 levels in 52 patients, both before graft and 3, 6, 9 and 12 months after graft, in reference to 50 healthy controls. CEC, EMP and sVCAM-1 levels were significantly decreased 1 year after transplantation (M12) as compared to pretransplant values. At M12, CEC and sVCAM-1 levels were significantly higher than those of controls whereas EMP reached normal values. Nine months postgraft, lower CEC and normalized EMP levels were found in patients receiving cyclosporine microemulsion/ azathioprine (CsA/Aza) when compared to patients treated with tacrolimus/ mycophenolate mofetil (Tac/MMF). Multivariate analysis evidenced positive correlations between CEC and history of cardiovascular diseases and between EMP and cytomegalovirus infection at M12. In conclusion, our combined analysis of endothelial injury markers confirms the favorable impact of renal transplantation on endothelium, and show that CEC levels discriminate treatment-associated endothelial toxicity. These results enlighten the potential of these noninvasive blood biomarkers in indexing vascular injury and optimize therapeutic options.


Assuntos
Biomarcadores/metabolismo , Endotélio Vascular/efeitos dos fármacos , Imunossupressores/uso terapêutico , Transplante de Rim/métodos , Adulto , Doenças Cardiovasculares/terapia , Estudos de Coortes , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/análogos & derivados , Estudos Prospectivos , Tacrolimo/administração & dosagem , Molécula 1 de Adesão de Célula Vascular/sangue
11.
Rev Med Interne ; 29(10): 794-800, 2008 Oct.
Artigo em Francês | MEDLINE | ID: mdl-18023939

RESUMO

PURPOSE: Thrombotic thrombocytopenic purpura (TTP) is a life-threatening disorder and early treatment is vital. Here, we review the recent advances in the understanding of the pathophysiology of TTP and its treatment. CURRENT KNOWLEDGE AND KEY POINTS: Recent advances have shown that TTP is caused by deficiency of the (ADAMTS-13) metalloprotease that cleaves von Willebrand factor multimers. Acquired TTP is associated to inhibitory antibodies directed against ADAMTS-13. This has led to assess new therapeutic approaches in refractory and relapsing forms of TTP and the use of rituximab has shown very encouraging results. FUTURE PROSPECTS AND PROJECTS: A better characterization of TTP amongst the other thrombotic microangiopathies has allowed the use of new therapeutic approaches with the use of rituximab. The encouraging results reported with rituximab in some forms of TTP challenge the classic treatment based on plasma exchanges.


Assuntos
Púrpura Trombocitopênica Trombótica/diagnóstico , Púrpura Trombocitopênica Trombótica/terapia , Corticosteroides/uso terapêutico , Diagnóstico Diferencial , Humanos , Troca Plasmática , Inibidores da Agregação Plaquetária/uso terapêutico , Púrpura Trombocitopênica Trombótica/epidemiologia , Púrpura Trombocitopênica Trombótica/fisiopatologia
12.
J Clin Invest ; 104(1): 93-102, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10393703

RESUMO

Microparticles (MPs) resulting from vesiculation of platelets and other blood cells have been extensively documented in vitro and have been found in increased numbers in several vascular diseases, but little is known about MPs of endothelial origin. The aim of this study was to analyze morphological, immunological, and functional characteristics of MPs derived from human umbilical vein endothelial cells (HUVECs) stimulated by TNF, and to investigate whether these MPs are detectable in healthy individuals and in patients with a prothrombotic coagulation abnormality. Electron microscopy evidenced bleb formation on the membrane of TNF-stimulated HUVECs, leading to increased numbers of MPs released in the supernatant. These endothelial microparticles (EMPs) expressed the same antigenic determinants as the corresponding cell surface, both in resting and activated conditions. MPs derived from TNF-stimulated cells induced coagulation in vitro, via a tissue factor/factor VII-dependent pathway. The expression of E-selectin, ICAM-1, alphavbeta3, and PECAM-1 suggests that MPs have an adhesion potential in addition to their procoagulant activity. In patients, labeling with alphavbeta3 was selected to discriminate EMPs from those of other origins. We provide evidence that endothelial-derived MPs are detectable in normal human blood and are increased in patients with a coagulation abnormality characterized by the presence of lupus anticoagulant. Thus, MPs can be induced by TNF in vitro, and may participate in vivo in the dissemination of proadhesive and procoagulant activities in thrombotic disorders.


Assuntos
Síndrome Antifosfolipídica/sangue , Doenças Autoimunes/sangue , Endotélio Vascular/ultraestrutura , Inibidor de Coagulação do Lúpus/sangue , Lúpus Eritematoso Sistêmico/sangue , Trombofilia/etiologia , Moléculas de Adesão Celular/análise , Células Cultivadas , Endotélio Vascular/efeitos dos fármacos , Fator VII/fisiologia , Citometria de Fluxo , Humanos , Infecções/sangue , Microscopia Confocal , Neoplasias/sangue , Receptores de Vitronectina/fisiologia , Trombofilia/sangue , Tromboplastina/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Veias Umbilicais
13.
J Thromb Haemost ; 5(6): 1302-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17403109

RESUMO

BACKGROUND: Endothelial dysfunction and oxidative stress are matters of concern in patients with chronic renal failure (CRF). Uremic solutes retained in these patients could be involved in these processes. Notably, the protein-bound uremic solute indoxyl sulfate induces endothelial dysfunction in vitro, and has shown pro-oxidant effects. OBJECTIVE: To demonstrate that indoxyl sulfate is a potential mediator of oxidative stress in endothelial cells in vitro. METHODS: Indoxyl sulfate-induced oxidative stress in human umbilical vein endothelial cells (HUVEC) was studied by measuring reactive oxygen specie (ROS) production by cytofluorimetry, by analyzing the involvement of the pro-oxidative enzymes NAD(P)H oxidase, xanthine oxidase, and NO synthase, and by measuring the levels of the non-enzymatic antioxidant glutathione. RESULTS: We showed that indoxyl sulfate induced a significant production of ROS in HUVEC, with or without human serum albumin. We then investigated the role of pro-oxidative enzymes and measured the levels of the antioxidant glutathione. The NAD(P)H oxidase inhibitors, DPI, and apocynin, inhibited ROS production, whereas inhibitors of xanthine oxidase, NO synthase, and mitochondrial ROS had no effect. Interestingly, indoxyl sulfate strongly decreased the levels of glutathione, one of the most active antioxidant systems of the cell. In addition, the ROS production mediated by indoxyl sulfate was inhibited by the antioxidants vitamin C, vitamin E, and NAC. CONCLUSION: The uremic solute indoxyl sulfate enhances ROS production, increases NAD(P)H oxidase activity, and decreases glutathione levels in endothelial cells. Thus, indoxyl sulfate induces oxidative stress by modifying the balance between pro- and antioxidant mechanisms in endothelial cells.


Assuntos
Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Indicã/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Uremia/metabolismo , Antioxidantes/farmacologia , Sequência de Bases , Células Cultivadas , Humanos , Indicã/metabolismo , NADPH Oxidases/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo III/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Xantina Oxidase/metabolismo
14.
J Thromb Haemost ; 5(8): 1630-6, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17488353

RESUMO

BACKGROUND: Despite dual antiplatelet therapy, the rate of major adverse cardiovascular events (MACE) after percutaneous coronary angioplasty remains high. Studies have shown interindividual variations in response to clopidogrel. Furthermore, there is an apparent link between clinical outcomes and clopidogrel resistance. OBJECTIVES: To investigate the value of platelet reactivity index (PRI), assessed by vasodilator-stimulated phosphoprotein (VASP) phosphorylation analysis, for predicting MACE after percutaneous coronary intervention (PCI) with stent implantation. METHODS: A prospective monocentric study was performed on 144 patients undergoing PCI. PR was evaluated by VASP phosphorylation analysis 24 h after they received a 300-mg loading dose of clopidogrel. MACE were recorded during a 6-month follow-up. Patients were divided into quintiles according to PRI, as assessed by VASP analysis. The receiver operating characteristic (ROC) curve served to determine the optimal cut-off value of VASP analysis to detect MACE. RESULTS: Of the 144 patients, 34% had stable angina pectoris, 40% silent ischemia, and 26% low-risk non-ST-segment elevation acute coronary syndrome. During the follow-up, 21 MACE were observed. Patients in quintile 1 of VASP analysis had a significantly lower risk of MACE as compared with those among the four higher quintiles (0 vs. 21, P < 0.01). ROC curve analysis of VASP showed an optimal cut-off value of 50% PR to exclude MACE. The negative predictive value of the test was 100%. CONCLUSIONS: VASP phosphorylation analysis can evaluate the individual response to clopidogrel loading dose prior to PCI and predict postprocedural MACE.


Assuntos
Angioplastia Coronária com Balão/métodos , Doenças Cardiovasculares/terapia , Moléculas de Adesão Celular/biossíntese , Proteínas dos Microfilamentos/biossíntese , Fosfoproteínas/biossíntese , Vasodilatadores/farmacologia , Idoso , Plaquetas/metabolismo , Doenças Cardiovasculares/prevenção & controle , Moléculas de Adesão Celular/química , Clopidogrel , Feminino , Humanos , Masculino , Proteínas dos Microfilamentos/química , Pessoa de Meia-Idade , Fosfoproteínas/química , Fosforilação , Inibidores da Agregação Plaquetária/farmacologia , Valor Preditivo dos Testes , Estudos Prospectivos , Ticlopidina/análogos & derivados , Ticlopidina/farmacologia
15.
Ann N Y Acad Sci ; 1108: 457-65, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17894010

RESUMO

The aim of this prospective study was to assess the prevalence of antiphospholipid antibodies (aPL) in women who had undergone in vitro fertilization (IVF) and the relationship between aPL and IVF outcome. A total of 101 infertile women with at least three unsuccessful IVF attempts were consecutively included in this study. Samples were collected in the follicular phase of a spontaneous ovarian cycle 2 months after the last ovulation induction treatment. Age-matched healthy fertile women (n = 160) were included as controls. All were evaluated for the presence of lupus anticoagulant (LA), antibodies (IgG, IgA, IgM) to cardiolipin (aCL), beta2-glycoprotein I (abeta2GPI), and phosphatidylethanolamine (aPE). Out of the 101 infertile women, 40 were persistently positive for aPL, showing a prevalence significantly higher than in controls (39.6% versus 5%, P < 0.0001). Among aPL, aPE were found with a significantly higher prevalence compared with LA, aCL, and aP2GPI (67.5% versus 0%, 15%, and 40%, respectively). Interestingly, aPE were found in 70% of the cases in the absence of the other aPL. The predominant isotype of aPL was IgA, in particular for abeta2GPI. Finally, no significant association was found between the presence of aPL and IVF outcome. This prospective study shows aPE as the most prevalent aPL in infertile women and IgA as more common than IgG and IgM. However, our results do not support an association between aPL and IVF outcome.


Assuntos
Anticorpos Antifosfolipídeos/sangue , Autoanticorpos/sangue , Fertilização in vitro , Infertilidade/sangue , Adolescente , Adulto , Cardiolipinas/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Infertilidade/etiologia , Inibidor de Coagulação do Lúpus/imunologia , Fosfatidiletanolaminas/imunologia , Prevalência , Resultado do Tratamento , beta 2-Glicoproteína I/imunologia
16.
Int J Lab Hematol ; 39(1): 32-41, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27566136

RESUMO

INTRODUCTION: In daily practice in haematology laboratories, spurious increased MCHC induces an analytical alarm and needs prompt corrective action to ensure delivery of the right results to the clinicians. The aim of this study was to establish a 'decision tree' using the new parameters red blood cells (RBC-O) and haemoglobin (HGB-O) from the Sysmex XN-10 RET obtained by flow cytometry to deliver appropriate results. METHODS: From 128 unknown patients with MCHC > 365 g/L, all erythrocyte parameters including reticulocyte parameters were measured and analysed in parallel with blood smears, chemistry index and osmolarity. Differences between optical parameters (RBC-O, HGB-O) and usual parameters (RBC, HGB) obtained by impedance and photometry were reported also. RESULTS: Four groups were defined from observations: -RBC agglutination (n = 22); -optical interference (n = 17); -RBC disease (n = 18); and -others (n = 71). The use of RBC-O and HGB-O permitted efficient correction of the abnormalities when RBC agglutination and/or optical interference were present in 36 of 39 patients. Reticulocyte parameters permitted to elaborate an RBC score that allowed a highly sensitive detection of RBC disease patients (17/18). CONCLUSION: Based on new parameters, we propose a 'decision tree' that delivers time savings and supports biological interpretation in case of elevated MCHC.


Assuntos
Citometria de Fluxo/métodos , Hemoglobinas/metabolismo , Reticulócitos/metabolismo , Adulto , Feminino , Humanos , Masculino
17.
J Thromb Haemost ; 15(1): 187-193, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27662257

RESUMO

Essentials The clinical enumeration of microparticles (MPs) is hampered by a lack of standardization. A new strategy to standardize MP counts by flow cytometry was evaluated in a multicenter study. No difference was found between instruments using forward or side scatter as the trigger parameter. This study demonstrated that beads can be used as a standardization tool for MPs. Click to hear the ISTH Academy's webinar on microvesicles SUMMARY: Background Microparticles (MPs) are extracellular vesicles resulting from the budding of cellular membranes that have a high potential as emergent biomarkers; however, their clinical relevance is hampered by methodological enumeration concerns and a lack of standardization. Flow cytometry (FCM) remains the most commonly used technique with the best capability to determine the cellular origin of single MPs. However, instruments behave variably depending on which scatter parameter (forward (FSC) or side scatter (SSC)) provides the best resolution to discriminate submicron particles. To overcome this problem, a new approach, based on two sets of selected beads adapted to FSC or SSC-optimized instruments, was recently proposed to reproducibly enumerate platelet-derived MP counts among instruments with different optical systems. Objective The objective was to evaluate this strategy in an international workshop that included 44 laboratories accounting for 52 cytometers of 14 types. Methods/Results Using resolution capability and background noise level as criteria to qualify the instruments, the standardization strategy proved to be compatible with 85% (44/52) of instruments. All instruments correctly ranked the platelet MP (PMP) levels of two platelet-free plasma samples. The inter-laboratory variability of PMP counts was 37% and 28% for each sample. No difference was found between instruments using forward or side-scattered light as the relative sizing parameter. Conclusions Despite remaining limitations, this study is the first to demonstrate a real potential of bead-based strategies for standardization of MP enumeration across different FCM platforms. Additional standardization efforts are still mandatory to evaluate MPs' clinical relevance at a multicenter level.


Assuntos
Micropartículas Derivadas de Células , Citometria de Fluxo/normas , Calibragem , Humanos , Neutrófilos/metabolismo , Tamanho da Partícula , Plasma , Contagem de Plaquetas , Sensibilidade e Especificidade
18.
J Dev Orig Health Dis ; 8(4): 448-464, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28460648

RESUMO

Individuals born after intrauterine growth restriction (IUGR) have an increased risk of perinatal morbidity/mortality, and those who survive face long-term consequences such as cardiovascular-related diseases, including systemic hypertension, atherosclerosis, coronary heart disease and chronic kidney disease. In addition to the demonstrated long-term effects of decreased nephron endowment and hyperactivity of the hypothalamic-pituitary-adrenal axis, individuals born after IUGR also exhibit early alterations in vascular structure and function, which have been identified as key factors of the development of cardiovascular-related diseases. The endothelium plays a major role in maintaining vascular function and homeostasis. Therefore, it is not surprising that impaired endothelial function can lead to the long-term development of vascular-related diseases. Endothelial dysfunction, particularly impaired endothelium-dependent vasodilation and vascular remodeling, involves decreased nitric oxide (NO) bioavailability, impaired endothelial NO synthase functionality, increased oxidative stress, endothelial progenitor cells dysfunction and accelerated vascular senescence. Preventive approaches such as breastfeeding, supplementation with folate, vitamins, antioxidants, L-citrulline, L-arginine and treatment with NO modulators represent promising strategies for improving endothelial function, mitigating long-term outcomes and possibly preventing IUGR of vascular origin. Moreover, the identification of early biomarkers of endothelial dysfunction, especially epigenetic biomarkers, could allow early screening and follow-up of individuals at risk of developing cardiovascular and renal diseases, thus contributing to the development of preventive and therapeutic strategies to avert the long-term effects of endothelial dysfunction in infants born after IUGR.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/fisiopatologia , Retardo do Crescimento Fetal/fisiopatologia , Nefropatias/fisiopatologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Feminino , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/epidemiologia , Humanos , Recém-Nascido , Nefropatias/diagnóstico , Nefropatias/epidemiologia , Óxido Nítrico/fisiologia , Estresse Oxidativo/fisiologia , Vasodilatação/fisiologia
19.
Curr Res Transl Med ; 65(1): 40-43, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28340695

RESUMO

INTRODUCTION: Hand involvement confers a substantial handicap in work and daily activities in patients with Systemic sclerosis (SSc). Autologous adipose-derived stromal vascular fraction is as an easily accessible source of cells with regenerative effects. We previously performed a phase I open-label clinical trial (NTC01813279) assessing the safety of subcutaneous injection of autologous adipose-derived stromal vascular fraction. Six and 12-month data have been reported. As patients were followed in our medical centre, we report their longer-term outcome beyond the end of the trial. PATIENTS AND METHOD: Twelve females, mean age 54.5±10.3 years, initially enrolled in the clinical trial were assessed during a scheduled medical care, which took place between 22 and 30months after treatment. RESULTS: Multiple patient-reported outcomes showed sustained improvement, in comparison with the assessment performed just before surgery: 62.5% in the Cochin Hand Function Scale, 51.1% in the Scleroderma Health Assessment Questionnaire, 33.1% in hand pain, and 88.3% in the Raynaud Condition Score. A decrease in the number of digital ulcers number was noted. Mobility, strength and fibrosis of the hand also showed improvement. None of the 8 patients who had previously received iloprost infusion required new infusion. CONCLUSION: Despite the limits of an open label study, the data are in favour of the long-term safety of the adipose-derived stromal vascular fraction injection. Two randomized double blind, placebo-controlled trials of this therapeutic agent are ongoing in the USA (NCT02396238) and in France (NCT02558543) and will help determine the place of this innovative therapy for SSc patients.


Assuntos
Tecido Adiposo/citologia , Dedos , Doença de Raynaud/terapia , Escleroderma Sistêmico/terapia , Células Estromais/transplante , Adulto , Idoso , Fracionamento Celular , Células Endoteliais/citologia , Células Endoteliais/transplante , Feminino , Dedos/patologia , Seguimentos , Mãos , Humanos , Injeções Subcutâneas , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Doença de Raynaud/etiologia , Escleroderma Sistêmico/complicações , Úlcera Cutânea/etiologia , Úlcera Cutânea/terapia , Transplante Autólogo , Resultado do Tratamento
20.
J Thromb Haemost ; 4(3): 566-73, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16405517

RESUMO

BACKGROUND: Chronic renal failure patients are at high risk of cardiovascular events and display endothelial dysfunction, a critical element in the pathogenesis of atherosclerosis. Upon activation, the endothelium sheds microparticles, considered as markers of endothelial dysfunction that also behave as vectors of bioactive molecules. AIM: To measure plasma levels of endothelial microparticles (EMPs) in chronic renal failure patients (CRF), either undialyzed or hemodialyzed (HD), and to investigate the ability of uremic toxins to induce EMP release in vitro. METHODS: Circulating EMPs were numerated by flow cytometry, after staining of platelet-free plasma with phycoerythrin (PE)-conjugated anti-CD144 (CD144+ EMP) or anti-CD146 (CD146+ EMP) monoclonal antibodies. Platelet MP (CD41+ PMP), leukocyte MP (CD45+ leukocyte microparticles (LMP)), and annexin-V+ MPs were also counted. In parallel, MPs were counted in supernatant of human umbilical vein endothelial cells incubated with uremic toxins [oxalate, indoxyl sulfate, p-cresol, and homocysteine (Hcy)], at concentrations found in patients. RESULTS AND CONCLUSIONS: CD144+ EMP and CD146+ EMP levels were significantly higher in CRF and HD patients than in healthy subjects. Furthermore, annexin-V+ MPs were elevated in both groups of uremic patients, and CD41+ PMP and CD45+ LMP were increased in CRF and HD patients, respectively. In vitro, p-cresol and indoxyl sulfate significantly increased both CD146+ and annexin-V+ EMP release. Increased levels of circulating EMP in CRF and HD patients represent a new marker of endothelial dysfunction in uremia. The ability of p-cresol and indoxyl sulfate to increase EMP release in vitro suggests that specific uremic factors may be involved in EMP elevation in patients.


Assuntos
Células Endoteliais/metabolismo , Falência Renal Crônica/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Anexina A5/sangue , Anexina A5/metabolismo , Antígenos CD , Antígeno CD146/sangue , Antígeno CD146/metabolismo , Caderinas/sangue , Células Cultivadas , Cresóis/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Feminino , Humanos , Indicã/farmacologia , Falência Renal Crônica/patologia , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Diálise Renal , Toxinas Biológicas/farmacologia , Uremia/sangue , Uremia/patologia , Uremia/terapia
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