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2.
Thromb Haemost ; 107(4): 769-74, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22318706

RESUMO

Erythropoietin improves myocardial function and enhances re-endothelialisation. Aim of this study was to analyse progenitor cell mobilisation and restenosis in patients from the Regeneration of Vital Myocardium in ST-Segment Elevation Myocardial Infarction by Erythropoietin (REVIVAL-3) study. Patients with STEMI undergoing percutaneous coronary intervention (PCI) were randomly assigned to Epoetin beta (EPO) (n=68) or placebo (n=70). Drug-eluting stents (DES) were utilised in 93% of patients receiving EPO and in 95% of patients receiving placebo (p=0.83). Serial venous blood samples were drawn; CD133+ progenitor cells were quantified by four-colour flow cytometry and cytokines interleukin (IL)-1ß, IL-6, IL-8, IL-10, IL-12 and tumour necrosis factor (TNF) alpha were analysed by cytometric bead array. Forty-eight hours after PCI a significant increase in CD133+ progenitor cells was observed in the EPO group. Yet, no differences in plasma cytokines were found. Quantitative coronary angiography after six months revealed an increase in segment diameter stenosis in the EPO group (32 ± 19% vs. 26 ± 14%, p=0.046). However, this increase in neointima generation was not associated with progenitor cell mobilisation. EPO in patients with STEMI treated with PCI is associated with an increase in diameter stenosis that is not associated with circulating progenitor cells.


Assuntos
Eritropoetina/metabolismo , Interleucinas/metabolismo , Infarto do Miocárdio/metabolismo , Células-Tronco/citologia , Angiografia/métodos , Citocinas/metabolismo , Stents Farmacológicos , Eritropoetina/uso terapêutico , Citometria de Fluxo/métodos , Mobilização de Células-Tronco Hematopoéticas , Humanos , Inflamação , Placebos , Proteínas Recombinantes/uso terapêutico , Fatores de Tempo , Resultado do Tratamento
3.
Atherosclerosis ; 212(2): 466-71, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20708733

RESUMO

OBJECTIVE: Within atherosclerotic lesions Tissue Factor (TF)-Factor VIIa (FVIIa) not only contributes to thrombotic events but also alters vascular remodeling through enhancement of migration. Moreover, the TF-FVIIa-FXa complex activates protease-activated receptors (PAR). TF/FVIIa/PAR-2 signaling has also been shown to promote proliferation and metastasis of tumor cells. Since coagulation factors promote inflammation which plays a major role during atherosclerosis as well as tumor metastasis this study sought to investigate the effects of FVIIa on the inflammatory response in vascular cells. METHODS/RESULTS: FVIIa induces interleukin-8 (IL-8) and IL-6 in primary smooth muscle cells (SMC), which was correlated to the expression of TF and PAR-2 as shown by immunoassay and qRT-PCR. The effect was dose-dependent and required TF, the proteolytic activity of FVIIa and PAR-2. Secondary effects of downstream coagulation factors were excluded. No proinflammatory FVIIa effect was observed in endothelial cells (EC) and mononuclear cells (MNC), expressing either TF or PAR-2. In atherosclerotic lesions mRNA expression of PAR-1, PAR-2 and IL-8 was elevated compared to healthy vessels indicating a role for PAR-1 and PAR-2 signaling in atherosclerosis. CONCLUSION: In addition to the procoagulant and promigratory role of the TF-FVIIa complex we identify a proinflammatory role of FVIIa in human SMC dependent on expression of TF and PAR-2 that provides yet another link between coagulation and inflammation.


Assuntos
Vasos Coronários/citologia , Citocinas/biossíntese , Fator VIIa/metabolismo , Regulação da Expressão Gênica , Miócitos de Músculo Liso/citologia , Tromboplastina/metabolismo , Coagulação Sanguínea , Membrana Celular/metabolismo , Humanos , Inflamação , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Interferência de RNA , Receptor PAR-1/metabolismo , Receptor PAR-2/metabolismo
4.
J Thromb Haemost ; 8(2): 250-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19943882

RESUMO

BACKGROUND: In patients undergoing percutaneous coronary intervention (PCI), a link between bleeding and excess mortality has been demonstrated. A potential association of platelet response to clopidogrel and bleeding has not been well established yet. OBJECTIVES: The aim of the present study was to assess the impact of clopidogrel responsiveness on the risk of bleeding in clopidogrel-treated patients undergoing PCI. METHODS: Patients (n=2533) undergoing PCI after pretreatment with 600 mg of clopidogrel were enrolled in this study. Blood was obtained directly before PCI. Adenosine-diphosphate (ADP)-induced platelet aggregation was assessed on a Multiplate analyzer. The primary endpoint was the incidence of in-hospital Thrombolysis in Myocardial Infarction (TIMI) major bleeding and the secondary endpoint was in-hospital TIMI minor bleeding. Receiver-operator curve (ROC) analysis was used to derive the optimal platelet aggregation value defining enhanced clopidogrel responders for the association of measurements with major bleeding. RESULTS: Thirty-four (1.3%) major bleeding events and 137 (5.4%) minor bleeding events were observed. The risk of a major bleeding was significantly higher in patients (n=975) with an enhanced response to clopidogrel as compared with the remaining patients (n=1558) (2.2 vs. 0.8%, unadjusted odds ratio (OR) 2.6, 95% confidence interval (CI) 1.3-5.2, P=0.005; adjusted OR 3.5, 95% CI 1.6-7.3, P=0.001). No significant differences between both groups were observed for the occurrence of minor bleeding events (P=0.68). CONCLUSIONS: Enhanced clopidogrel responsiveness is associated with a higher risk of major bleeding. Whether guidance of antiplatelet treatment based on platelet function testing proves useful for avoiding bleeding events warrants further investigation.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Doença da Artéria Coronariana/terapia , Stents Farmacológicos , Hemorragia/induzido quimicamente , Inibidores da Agregação Plaquetária/efeitos adversos , Agregação Plaquetária/efeitos dos fármacos , Trombose/prevenção & controle , Ticlopidina/análogos & derivados , Difosfato de Adenosina , Idoso , Angioplastia Coronária com Balão/efeitos adversos , Distribuição de Qui-Quadrado , Clopidogrel , Doença da Artéria Coronariana/sangue , Feminino , Alemanha , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Testes de Função Plaquetária , Valor Preditivo dos Testes , Curva ROC , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Trombose/sangue , Trombose/etiologia , Ticlopidina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
5.
Cardiology ; 112(4): 263-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18758183

RESUMO

OBJECTIVE: Drug-eluting stents (DES) have reduced restenosis rates compared with bare-metal stents. P27 and P53 play important roles in the signal transduction leading to neointimal growth inhibition and induction of apoptosis of smooth muscle cells due to rapamycin and paclitaxel. We hypothesized that genetic variants of P27 and P53 influence the development of restenosis and the clinical outcome of patients receiving DES. METHODS: Polymorphisms in the genes encoding for P27 and P53 were tested for their association with restenosis and major adverse cardiac events. P27 C-79T and P53 G72C polymorphism genotypes were determined in a series of 433 consecutive patients receiving DES. Follow-up angiography after 6 months was performed in 87% of the patients. Genotyping was performed with PCR-based methods. RESULTS: For patients with the respective P27 C-79T and P53 G72C genotypes, the angiographic restenosis rates were between 5.0 and 22.0%, and the clinical restenosis rates were between 0.0 and 16.3%, without significant differences for the studied genotypes (p > 0.19). There was no association of the studied genotypes with the 1-year incidences of death and myocardial infarction. CONCLUSION: This study could not demonstrate a clinically relevant role of P27 and P53 polymorphisms in the processes leading to in-stent restenosis.


Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana/terapia , Inibidor de Quinase Dependente de Ciclina p27/genética , Stents Farmacológicos/efeitos adversos , Oclusão de Enxerto Vascular/genética , Polimorfismo Genético , Proteína Supressora de Tumor p53/genética , Idoso , Estudos de Coortes , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Transdução de Sinais
6.
Eur J Clin Invest ; 38(2): 90-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18226042

RESUMO

BACKGROUND: No studies have measured plasma myeloperoxidase (MPO) across the entire spectrum of patients with coronary artery disease (CAD). The aim of the study was to compare MPO level across the entire spectrum of CAD, to assess the accuracy of MPO in predicting acute coronary syndromes and to define independent correlates of MPO level. DESIGN: This case-control study included 874 patients with angiographically proven CAD. Cases included 680 patients with CAD (382 patients with stable CAD, 107 patients with non-ST-segment elevation acute coronary syndromes and 191 patients with ST-segment elevation acute myocardial infarction). Controls included 194 subjects with normal coronary angiograms. MPO was measured using an enzyme immunoassay before angiography and heparin administration. RESULTS: MPO level [median (25th-75th percentiles)] was 74.5 (52.5-135.3) microg L(-1) in cases vs. 61.2 (44.6-80.9), microg L(-1) in controls (P < 0.001). MPO level was 61.2 (47.5-85.8), microg L(-1) in patients with stable CAD, 99.2 (62.2-154.9), microg L(-1) in patients with non-ST-segment elevation acute coronary syndromes and 129.5 (72.2-216.0) microg L(-1) in patients with acute myocardial infarction (P < 0.001). Elevated MPO level was associated with acute coronary syndromes with an area under receiver operating characteristic (ROC) curve of 0.731 (95% confidence interval 0.692-0.770; P < 0.001). Independent correlates of MPO level were acute coronary syndrome (P < 0.001), high-sensitivity C-reactive protein (P = 0.007), creatinine (P = 0.026), left ventricular ejection fraction (P = 0.027, negative association) and smoking (P = 0.028). CONCLUSIONS: MPO level is elevated in patients with CAD and higher levels of MPO were found with progression of CAD from stable CAD to non-ST-segment elevation acute coronary syndromes and to acute myocardial infarction.


Assuntos
Síndrome Coronariana Aguda/sangue , Doença da Artéria Coronariana/sangue , Peroxidase/análise , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peroxidase/sangue , Valor Preditivo dos Testes
9.
Minerva Cardioangiol ; 54(1): 5-22, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16467738

RESUMO

Drug-eluting stents (DES) are playing an increasingly important role in the treatment of coronary artery disease. These new devices work by releasing controlled amounts of pharmacological agents with anti-restenosis properties at the implantation site. Most of them use polymer coating as a drug carrier, but concerns about long-term negative effects of a permanent polymer coating have stimulated the development of non-polymer DES or DES based on bioabsorbable polymers. Several randomized studies with DES have demonstrated their superiority over bare metal stents mostly in selected patients and lesion subsets. Accumulating evidence is showing significant differences in performance between currently used DES. These differences are more pronounced in complex, high-risk subsets of patients and lesions and should be considered during the process of DES selection for the individual patient. Interventional cardiologists have learned that patients who receive DES require a more prolonged antiplatelet therapy, but the optimal length and regimen are still unclear and further investigations are needed. Major advances in interventional cardiology have caused a dramatic shift away from aorto-coronary bypass surgery and an increase in the complexity of percutaneous coronary interventions. Observational and specifically designed randomized studies are currently addressing the issue of the role of DES in complex situations including in-stent restenosis, ostial and bifurcation lesions, chronic occlusions, small vessels, long lesions, saphenous vein grafts, multivessel disease, left main disease, acute myocardial infarction and diabetes mellitus. Although definitive answers are still to come from ongoing research, available data support the use of DES in most of these situations.


Assuntos
Angioplastia Coronária com Balão , Fármacos Cardiovasculares/administração & dosagem , Doença da Artéria Coronariana/terapia , Reestenose Coronária/prevenção & controle , Stents , Angioplastia Coronária com Balão/métodos , Angiopatias Diabéticas/terapia , Vias de Administração de Medicamentos , Humanos , Inibidores da Agregação Plaquetária/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Vasa ; 31(2): 95-9, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12099152

RESUMO

BACKGROUND: It is unknown, whether direct guidance by ultrasound is essential for the safety and efficacy of ultrasound-guided compression repair (UGCR) of pseudoaneurysms. We therefore tested, whether clinically guided manual compression repair (MCR) without continuous ultrasound control may represent an equally effective alternative. METHODS: After ultrasound diagnosis of a pseudoaneurysm, direct manual compression was applied to the lesion until the characteristic clinical signs disappeared or for a maximum of 1 hour. Then a compression bandage was applied for 24 hours. If the pseudoaneurysm persisted, MCR was repeated up to a maximum of three times. RESULTS: Of 96 consecutive patients with pseudoaneurysms, ten patients were referred to primary surgery; one patient refused any therapy. The remaining 85 patients (89%) were treated by MCR. MCR was successful in 74 patients (87%). Of these, 74% were cured at the first attempt, while 16% resp. 10% required 2 resp. 3 compression manoeuvers for definite cure. The success rate tended to be somewhat lower in patients on anticoagulants (78%) than in those on aspirin (91%) or those without any antithrombotic medication (89%) (p = 0.14). No major complications were observed. Of the 11 patients in whom MCR was unsuccessful, five patients underwent surgical repair; in four patients the pseudoaneurysms thrombosed spontaneously within 1-3 months and 2 pseudoaneurysms persist without complications. CONCLUSIONS: Our results with MCR are comparable to those published for UGCR. Since MCR requires less technical equipment and seems to be less painful for the patient, a prospective comparison of both methods appears warranted.


Assuntos
Falso Aneurisma/terapia , Artéria Femoral/lesões , Técnicas Hemostáticas , Adulto , Idoso , Idoso de 80 Anos ou mais , Falso Aneurisma/diagnóstico por imagem , Cateterismo Cardíaco/efeitos adversos , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Retratamento , Ultrassonografia
11.
Hum Gene Ther ; 12(17): 2051-63, 2001 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11747596

RESUMO

Cardiac myocyte apoptosis has been demonstrated in end-stage failing human hearts. The therapeutic utility of blocking apoptosis in congestive heart failure (CHF) has not been elucidated. This study investigated the role of caspase activation in cardiac contractility and sarcomere organization in the development of CHF. In a rabbit model of heart failure obtained by rapid ventricular pacing, we demonstrate, using in vivo transcoronary adenovirus-mediated gene delivery of the potent caspase inhibitor p35, that caspase activation is associated with a reduction in contractile force of failing myocytes by destroying sarcomeric structure. In this animal model gene transfer of p35 prevented the rise in caspase 3 activity and DNA-histone formation. Genetically manipulated hearts expressing p35 had a significant improvement in left ventricular pressure rise (+dp/dt), decreased end-diastolic chamber pressure (LVEDP), and the development of heart failure was delayed. To better understand this benefit, we examined the effects of caspase 3 on cardiomyocyte dysfunction in vitro. Microinjection of activated caspase 3 into the cytoplasm of intact myocytes induced sarcomeric disorganization and reduced contractility of the cells. These results demonstrate a direct impact of caspases on cardiac function and may lead to novel therapeutic strategies via antiapoptotic regimens.


Assuntos
Apoptose , Inibidores de Caspase , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/patologia , Contração Miocárdica , Miocárdio/enzimologia , Miocárdio/patologia , Adenoviridae/genética , Animais , Peso Corporal , Caspase 3 , Caspases/administração & dosagem , Caspases/metabolismo , Caspases/farmacologia , Células Cultivadas , Inibidores de Cisteína Proteinase/uso terapêutico , Fragmentação do DNA , Expressão Gênica , Terapia Genética/métodos , Vetores Genéticos/genética , Proteínas de Fluorescência Verde , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/terapia , Ventrículos do Coração/enzimologia , Ventrículos do Coração/fisiopatologia , Proteínas Luminescentes , Masculino , Miocárdio/metabolismo , Tamanho do Órgão , Marca-Passo Artificial , Coelhos , Ratos , Sarcômeros/enzimologia , Sarcômeros/metabolismo , Sarcômeros/patologia , Taquicardia/fisiopatologia , Fatores de Tempo , Transgenes/genética
12.
Atherosclerosis ; 159(1): 137-44, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11689215

RESUMO

Inflammation plays an important role in the pathogenesis of atherosclerosis and acute coronary syndromes. Cytokines IL-10 and TNF-alpha exert opposite functions in inflammatory reactions, IL-10 acting predominantly as an antiinflammatory and TNF-alpha as a proinflammatory factor. Functional single nucleotide polymorphisms in the genes of IL-10, TNF-alpha, and TNF-beta are associated with gene expression and plasma levels of IL-10 and TNF-alpha. The aim of the study was to assess whether these IL-10 and TNF gene polymorphisms are related to the risk of coronary artery disease (CAD) and myocardial infarction (MI). Consecutive, angiographically examined patients with significant coronary stenoses but without symptoms or signs of old or acute MI constituted the group with CAD (n=998) and patients with old or acute MI constituted the group with MI (n=793). Subjects with neither angiographic CAD nor symptoms or signs of MI (n=340) served as controls. They were matched with the patients for age and sex. Genotyping was performed with techniques based on the polymerase chain reaction. Allele frequencies, genotype distributions, and frequencies of allele combinations for three IL-10 promoter polymorphisms, -1082G/A, -819C/T and -592C/A, were similar between CAD patients, MI patients, and matched controls. Similarly, genetic analysis did not reveal group-specific differences for the TNF-alpha promoter polymorphisms -863C/A and -308G/A, as well as for the TNF-beta intron 1 polymorphism 252G/A. In addition, no relationship was found between specific combinations of IL-10 and TNF alleles, indicative of low IL-10 and high TNF-alpha production, respectively, and CAD or MI. The lack of association persisted also after adjusting for other cardiovascular risk factors. Our findings suggest that six different and functionally relevant polymorphisms of the genes coding for IL-10, TNF-alpha, and TNF-beta are neither separately nor in cooperation associated with the risk of CAD or MI in angiographically examined patients.


Assuntos
Doença das Coronárias/genética , Interleucina-10/genética , Linfotoxina-alfa/genética , Infarto do Miocárdio/genética , Polimorfismo Genético , Fator de Necrose Tumoral alfa/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Fatores de Risco
13.
Circulation ; 104(10): 1135-9, 2001 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-11535569

RESUMO

BACKGROUND: Reactivated cytomegalovirus may promote neointima formation after percutaneous coronary interventions by facilitating cell cycle progression through inhibition of the eukariotic tumor suppressor protein p53. This prospective study sought to investigate the effect of previous cytomegalovirus infection on restenosis after coronary stenting. METHODS AND RESULTS: In 551 consecutive patients with successful stent placement, we determined cytomegalovirus IgG titers. Primary and secondary end points were the rate of angiographic restenosis at 6 months and the rate of target vessel reintervention at 1 year, respectively. Three hundred forty patients (62%) had a positive cytomegalovirus IgG titer. We obtained angiographic follow-up in 82% of all patients. Angiographic restenosis rate was 28.7% in patients with positive cytomegalovirus titers and 34.6% in patients with negative titers (P=0.18). Between the groups with and without positive cytomegalovirus titers, there were no significant differences in late lumen loss (1.16+/-0.90 mm and 1.23+/-0.86 mm, respectively, P=0.44). Target vessel reintervention was performed in 16.8% of the patients with positive cytomegalovirus titers and in 17.5% of those without (P=0.82). Even after correction for potential confounding variables by multivariate analysis, positive cytomegalovirus titers did not manifest as a predictor of angiographic restenosis (adjusted odds ratio [95% confidence interval], 0.78 [0.52 to 1.19]). CONCLUSIONS: Previous cytomegalovirus infection does not carry an increased risk of restenosis after stenting.


Assuntos
Doença das Coronárias/sangue , Infecções por Citomegalovirus/complicações , Stents , Idoso , Anticorpos Antivirais/sangue , Estudos de Coortes , Angiografia Coronária , Doença das Coronárias/etiologia , Doença das Coronárias/terapia , Vasos Coronários/patologia , Vasos Coronários/fisiopatologia , Citomegalovirus/genética , Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , DNA Viral/sangue , Feminino , Seguimentos , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco
14.
Circ Res ; 88(7): 688-95, 2001 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-11304491

RESUMO

In heart failure, reduced cardiac contractility is accompanied by blunted cAMP responses to beta-adrenergic stimulation. Parathyroid hormone (PTH)-related peptide and arginine vasopressin are released from the myocardium in response to increased wall stress but do not stimulate contractility or adenylyl cyclase at physiological concentrations. To bypass the defective beta-adrenergic signaling cascade, recombinant P1 PTH/PTH-related peptide receptors (rPTH1-Rs) and V(2) vasopressin receptors (rV(2)-Rs), which are normally not expressed in the myocardium and which are both strongly coupled to adenylyl cyclase, and recombinant beta(2)-adrenergic receptors (rbeta(2)-ARs) were overexpressed in cardiomyocytes by viral gene transfer. The capacity of endogenous hormones to increase contractility via the heterologous, recombinant receptors was compared. Whereas V(2)-Rs are uniquely coupled to Gs, PTH1-Rs and beta(2)-ARs are also coupled to other G proteins. Gene transfer of rPTH1-Rs or rbeta(2)-ARs to adult cardiomyocytes resulted in maximally increased basal contractility, which could not be further stimulated by adding receptor agonists. Agonists at rPTH1-Rs induced increased cAMP formation and phospholipase C activity. In contrast, healthy or failing rV(2)-R-expressing cardiomyocytes showed unaltered basal contractility. Their contractility and cAMP formation increased only at agonist exposure, which did not activate phospholipase C. In summary, we found that gene transfer of PTH1-Rs to cardiomyocytes results in constitutive activity of the transgene, as does that of beta(2)-ARS: In the absence of receptor agonists, rPTH1-Rs and rbeta(2)-ARs increase basal contractility, coupling to 2 G proteins simultaneously. In contrast, rV(2)-Rs are uniquely coupled to Gs and are not constitutively active, retaining their property to be activated exclusively on agonist stimulation. Therefore, gene transfer of V(2)-Rs might be more suited to test the effects of cAMP-stimulating receptors in heart failure than that of PTH1-Rs or beta(2)-ARS:


Assuntos
Proteínas de Ligação ao GTP/metabolismo , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Hormônios Paratireóideos/metabolismo , Adenoviridae/genética , Toxina Adenilato Ciclase , Animais , Arginina Vasopressina/metabolismo , Meios de Cultivo Condicionados/metabolismo , AMP Cíclico/metabolismo , Desamino Arginina Vasopressina/farmacologia , Relação Dose-Resposta a Droga , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Vetores Genéticos/farmacologia , Proteínas de Fluorescência Verde , Insuficiência Cardíaca/metabolismo , Proteínas Luminescentes/genética , Contração Miocárdica/efeitos dos fármacos , Contração Miocárdica/genética , Miocárdio/citologia , Hormônio Paratireóideo/farmacologia , Proteína Relacionada ao Hormônio Paratireóideo , Fragmentos de Peptídeos/farmacologia , Proteínas/metabolismo , Coelhos , Ensaio Radioligante , Receptores de Superfície Celular/genética , Receptores de Hormônios Paratireóideos/genética , Receptores de Vasopressinas/genética , Receptores de Vasopressinas/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transgenes/genética , Fosfolipases Tipo C/metabolismo , Fatores de Virulência de Bordetella/farmacologia
15.
J Am Coll Cardiol ; 37(5): 1323-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11300442

RESUMO

OBJECTIVES: We sought to investigate whether abciximab, tirofiban and eptifibatide achieve comparable antiplatelet effects with coronary stenting. BACKGROUND: The glycoprotein (GP) IIb/IIIa antagonists abciximab, tirofiban and eptifibatide differ in chemical structure, binding site and pharmacokinetics. METHODS: Sixty patients undergoing coronary stenting were randomly assigned to abciximab (bolus 0.25 mg/kg body weight, infusion 10 microg per min for 12 h), tirofiban (bolus 10 microg/kg, infusion 0.15 microg/kg per min for 72 h) or eptifibatide (bolus 180 microg/kg, infusion 2 microg/kg per min for 72 h). We took serial blood samples to analyze platelet function by using flow cytometry, turbidimetric aggregometry and the rapid platelet-function assay (RPFA). RESULTS: As assessed by RPFA, platelet aggregation after 2 h of infusion was reduced to 5.9 +/- 7.8% (mean +/- SD) of baseline by abciximab, to 5.0 +/- 5.4% by tirofiban and to 7.8 +/- 7.1% by eptifibatide (p = 0.42). Turbidimetric aggregometry with adenosine diphosphate stimulation yielded similar results, whereas percent inhibition of platelet aggregation after thrombin receptor stimulation was 45.8 +/- 16.8% with abciximab, 51.3 +/- 17.6% with tirofiban and 52.9 +/- 14.8% with eptifibatide (p = 0.37). Tirofiban and eptifibatide maintained their level of platelet inhibition during infusion. Flow cytometry revealed that the reduction in the monocyte-platelet interaction by abciximab, tirofiban and eptifibatide was not significantly different (20.0 +/- 21.9%, 23.8 +/- 18.2% and 21.0 +/- 19.8%, respectively; p = 0.87). CONCLUSIONS: Abciximab, tirofiban and eptifibatide, at currently recommended doses, achieved similar levels of inhibition of platelet aggregation and a similar reduction in the platelet-monocyte interaction.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Doença das Coronárias/terapia , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Peptídeos/administração & dosagem , Inibidores da Agregação Plaquetária/administração & dosagem , Stents , Tirosina/análogos & derivados , Tirosina/administração & dosagem , Abciximab , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão , Anticorpos Monoclonais/efeitos adversos , Doença das Coronárias/sangue , Eptifibatida , Feminino , Humanos , Fragmentos Fab das Imunoglobulinas/efeitos adversos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Peptídeos/efeitos adversos , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/efeitos adversos , Tirofibana , Tirosina/efeitos adversos
16.
Am J Cardiol ; 87(4): 463-6, A7, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11179537

RESUMO

The objective of this randomized pilot trial with 21 patients was to evaluate the effectiveness of a rhenium-188 liquid-filled balloon system to prevent recurrent restenosis after percutaneous transluminal coronary angioplasty for in-stent restenosis. A significant benefit from brachytherapy was seen at 6-month repeat angiography, as well as during the clinical follow-up of 12 months.


Assuntos
Angioplastia com Balão/métodos , Braquiterapia/métodos , Doença das Coronárias/radioterapia , Radioisótopos , Rênio , Idoso , Angiografia Coronária , Doença das Coronárias/patologia , Doença das Coronárias/cirurgia , Feminino , Humanos , Masculino , Projetos Piloto , Recidiva , Stents , Análise de Sobrevida , Resultado do Tratamento
17.
Blood ; 96(2): 506-13, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10887112

RESUMO

During acute inflammatory processes, beta(2) and beta(1) integrins sequentially mediate leukocyte recruitment into extravascular tissues. We studied the influence of VLA-4 (very late antigen-4) (alpha(4)beta(1)) engagement on beta(2) integrin activation-dependent cell-to-cell adhesion. Ligation of VLA-4 by the soluble chimera fusion product vascular cell adhesion molecule-1 (VCAM-1)-Fc or by 2 anti-CD29 (beta(1) chain) monoclonal antibodies (mAb) rapidly induced adhesion of myelomonocytic cells (HL60, U937) to human umbilical vein endothelial cells (HUVECs). Cell adhesion was mediated via beta(2) integrin (LFA-1 and Mac-1) activation: induced adhesion to HUVECs was inhibited by blocking mAbs anti-CD18 (70%-90%), anti-CD11a (50%-60%), or anti-CD11b (60%-70%). Adhesion to immobilized ligands of beta(2) integrins (intercellular adhesion molecule-1 [ICAM-1], fibrinogen, keyhole limpet hemocyanin) as well as to ICAM-1-transfected Chinese hamster ovary cells, but not to ligands of beta(1) integrins (VCAM-1, fibronectin, laminin, and collagen), was augmented. VCAM-1-Fc binding provoked the expression of the activation-dependent epitope CBRM1/5 of Mac-1 on leukocytes. Clustering of VLA-4 through dimeric VCAM-1-Fc was required for beta(2) integrin activation and induction of cell adhesion, whereas monovalent VCAM-1 or Fab fragments of anti-beta(1) integrin mAb were ineffective. Activation of beta(2) integrins by alpha(4)beta(1) integrin ligation (VCAM-1-Fc or anti-beta(1) mAb) required the presence of urokinase receptor (uPAR) on leukocytic cells, because the removal of uPAR from the cell surface by phosphatidylinositol-specific phospholipase C reduced cell adhesion to less than 40%. Adhesion was reconstituted when soluble recombinant uPAR was allowed to reassociate with the cells. Finally, VLA-4 engagement by VCAM-1-Fc or anti-beta(1) integrin mAb induced uPAR-dependent adhesion to immobilized vitronectin as well. These results elucidate a novel activation pathway of beta(2) integrin-dependent cell-to-cell adhesion that requires alpha(4)beta(1) integrin ligation for initiation and uPAR as activation transducer. (Blood. 2000;96:506-513)


Assuntos
Antígenos CD18/fisiologia , Adesão Celular , Integrinas/fisiologia , Leucócitos/fisiologia , Receptores de Superfície Celular/fisiologia , Receptores de Retorno de Linfócitos/fisiologia , Anticorpos Monoclonais , Antígenos CD18/imunologia , Antígenos CD18/metabolismo , Endotélio Vascular/citologia , Humanos , Integrina alfa4beta1 , Antígeno-1 Associado à Função Linfocitária/fisiologia , Antígeno de Macrófago 1/fisiologia , Receptores Fc/fisiologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Células Tumorais Cultivadas , Veias Umbilicais , Molécula 1 de Adesão de Célula Vascular/imunologia , Molécula 1 de Adesão de Célula Vascular/metabolismo
18.
Thromb Haemost ; 83(6): 915-22, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10896249

RESUMO

Resting platelets contain a substantial internal pool of GPIIb-IIIa complexes that is exposed on the surface of activated platelets. Whether the exposure of internal GPIIb-IIIa complexes on the activated platelet surface affects therapy with GPIIb-IIIa antagonists is poorly understood. We addressed this issue in thirteen patients who underwent elective coronary stenting and received abciximab. Platelet aggregation, surface expression of GPIIb-IIIa and P-selectin, receptor blockade of GPIIb-IIIa, and platelet release in response to ADP and thrombin-receptor activating peptide (TRAP) were determined ex vivo by Lumi-aggregometry and flow cytometry before, during and after abciximab administration. We found that inhibition of aggregation and GPIIb-IIIa blockade of ADP-stimulated platelets was almost complete during abciximab administration. In contrast, when TRAP was used to stimulate platelets ex vivo aggregation was only partially inhibited, most likely due to release of internal pool of unblocked GPIIb-IIIa complexes. Using electron microscopy we found that 7E3-occupied GPIIb-IIIa complexes are internalized into the surface connected system (SCS) and the alpha-granules of washed platelets which was associated with a reduced degranulation of the alpha-granula membrane protein P-selectin. We conclude, that despite internalization of abciximab into the internal pool of GPIIb-IIIa, upon strong platelet activation with thrombin a significant amount of unblocked internal GPIIb-IIIa can be exposed on the platelet surface and mediate platelet aggregation. Incomplete blockade of the internal GPIIb-IIIa pool may limit clinical efficacy of abciximab.


Assuntos
Anticorpos Monoclonais/farmacologia , Fragmentos Fab das Imunoglobulinas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Abciximab , Difosfato de Adenosina/farmacologia , Trifosfato de Adenosina/metabolismo , Angina Pectoris/sangue , Angina Pectoris/tratamento farmacológico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/metabolismo , Anticoagulantes/farmacologia , Plaquetas/química , Plaquetas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Citometria de Fluxo , Humanos , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Fragmentos Fab das Imunoglobulinas/metabolismo , Glicoproteínas de Membrana/efeitos dos fármacos , Glicoproteínas de Membrana/metabolismo , Microscopia Eletrônica , Selectina-P/efeitos dos fármacos , Selectina-P/metabolismo , Fragmentos de Peptídeos/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Ligação Proteica , Receptores de Trombina/química , Fatores de Tempo
19.
J Psychosom Res ; 48(4-5): 501-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10880672

RESUMO

OBJECTIVES: In this study we evaluate gender differences in affective adaptation and health perception in patients 6 months after stent implantation. BACKGROUND: Assessment of gender-specific behavioral strategies to cope with serious cardiac disease conditions has not been given much attention until now. Preliminary data suggest greater impairments in female patients, which might be of clinical relevance. METHODS: Three hundred seventeen patients were eligible for the 6-month follow-up investigation, 78 (24.6%) of whom were women. The women were significantly older but did not differ from men in their cardiac risk features and treatment procedures. There were no gender differences in prevalence of hypertension, hypercholesterolemia, and family history. Men had a significantly higher prevalence of smoking than women, whereas women had a significantly higher prevalence of diabetes than men. A structured interview and a standardized psychodiagnostic assessment was carried out, which covered domains of affective dysfunction (depression, anxiety, intrusion, and avoidance), vegetative symptoms (sleeping disorders), and parameters of negative health perception. RESULTS: There were no significant gender differences in the prevalence of depressive symptoms. Women exhibited higher mean values of anxiety than men, which did not reach significance. Sleeping disorders were significantly more prevalent in women. The absolute level of being distressed by intrusive thoughts and avoidance behavior related to the severe underlying disease process was low in the total group of patients examined. Measurable gender differences did not emerge. Fifty-one (16.5%) patients exhibited pessimistic anticipation of dire consequences and severe signs of negative health perception (NHP group). There was a trend, although not statistically significant, toward more women being in the NHP group. The distribution of cardiac risk factors, however, was completely balanced in the NHP(+) and NHP(-) patient groups. Objective somatic cardiac disease parameters did not account for the negative health perception. NHP was, however, associated with significantly more prestent angina pectoris (p < 0.040) and poststent angina pectoris (p < 0.0001). High levels of anxiety, depression, and of disturbed sleep also led to a sharp separation between patients with high degrees of an anticipated incapacitation due to the disease process. Univariate regression analysis suggested an effect of female gender on the occurrence of NHP (odds ratio 1. 70; 95% CI 0.88 to 3.25), which was of borderline significance. Control for confounders in a multiple regression model, however, eliminated the gender effect (odds ratio 1.04, 95% CI 0.48 to 2.23). Poststent chest pain (odds ratio 7.75, 95% CI 3.28 to 18.32) and sleeping disorders (odds ratio 1.32, 95% CI 1.16 to 1.51) were identified as the most powerful confounders of the gender-NHP association. CONCLUSION: Contrary to expectation, women were not per se more distressed than men in all areas of adaptation of the midterm course after stent implantation, although the higher levels of anxiety and sleeping disorders in women deserve attention. A considerable proportion of patients exhibited a pessimistic disease perspective independent of their somatic status, which was associated with affective morbidity. The tendency toward more negative health perception in women may be due to their more frequent occurrence of chest pain and sleeping disorders.


Assuntos
Sintomas Afetivos/etiologia , Angioplastia Coronária com Balão/psicologia , Atitude Frente a Saúde , Doença das Coronárias/psicologia , Doença das Coronárias/cirurgia , Pessoas com Deficiência/psicologia , Nível de Saúde , Stents , Adaptação Psicológica , Idoso , Feminino , Seguimentos , Humanos , Expectativa de Vida , Masculino , Pessoa de Meia-Idade , Morbidade , Fatores de Risco , Fatores Sexuais
20.
Circulation ; 101(21): 2478-83, 2000 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-10831521

RESUMO

BACKGROUND: Gold is a highly biocompatible material. Experimental evidence suggests that coating the stent with a gold layer may have a beneficial influence. In this randomized trial, we assessed whether gold-coated stents were associated with a better clinical and angiographic outcome after coronary placement. METHODS AND RESULTS: Patients with symptomatic coronary artery disease were randomly assigned to receive either a gold-coated Inflow stent (n = 367) or an uncoated Inflow stainless steel stent (n = 364) of identical design. Follow-up angiography was routinely performed at 6 months. The primary end point of the study was the occurrence of any adverse clinical event (death, myocardial infarction, or target-vessel revascularization) during the first year after stenting. At 30 days, there was no significant difference in the combined incidence of adverse events, with 7.9% in the gold-stent group versus 5.8% in the steel-stent group (P = 0.25). The incidence of angiographic restenosis (> or =50% diameter stenosis) was 49.7% in the gold-stent group and 38.1% in the steel-stent group (P = 0.003). One-year survival free of myocardial infarction was 88.6% in the gold-stent group and 91.8% in the steel-stent group (P = 0.14). One-year event-free survival was significantly less favorable in the gold-stent group (62.9% versus 73.9% in the steel-stent group; P = 0.001). CONCLUSIONS: Coating steel stents with gold had no significant influence on the thrombotic events observed during the first 30 days after the intervention. However, gold-coated stents were associated with a considerable increase in the risk of restenosis over the first year after stenting.


Assuntos
Doença das Coronárias/terapia , Ouro , Stents , Idoso , Materiais Biocompatíveis , Angiografia Coronária , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Aço
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