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1.
Am J Transplant ; 17(9): 2390-2399, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28257169

RESUMO

Cystatin C and beta-2-microglobulin (B2M) are filtration markers associated with adverse outcomes in nontransplant populations, sometimes with stronger associations than for creatinine. We evaluated associations of estimated glomerular filtration rate from cystatin C (eGFRcys ), B2M (eGFRB2M ), and creatinine (eGFRcr ) with cardiovascular outcomes, mortality, and kidney failure in stable kidney transplant recipients using a case-cohort study nested within the Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) Trial. A random subcohort was selected (N = 508; mean age 51.6 years, median transplant vintage 4 years, 38% women, 23.6% nonwhite race) with enrichment for cardiovascular events (N = 306; 54 within the subcohort), mortality (N = 208; 68 within the subcohort), and kidney failure (N = 208; 52 within the subcohort). Mean eGFRcr , eGFRcys , and eGFRB2M were 46.0, 43.8, and 48.8 mL/min/1.73m2 , respectively. After multivariable adjustment, hazard ratios for eGFRcys and eGFRB2M <30 versus 60+ were 2.02 (95% confidence interval [CI] 1.09-3.76; p = 0.03) and 2.56 (1.35-4.88; p = 0.004) for cardiovascular events; 3.92 (2.11-7.31) and 4.09 (2.21-7.54; both p < 0.001) for mortality; and 9.49 (4.28-21.00) and 15.53 (6.99-34.51; both p < 0.001) for kidney failure. Associations persisted with additional adjustment for baseline eGFRcr . We conclude that cystatin C and B2M are strongly associated with cardiovascular events, mortality, and kidney failure in stable kidney transplant recipients.


Assuntos
Biomarcadores/metabolismo , Doenças Cardiovasculares/mortalidade , Rejeição de Enxerto/mortalidade , Falência Renal Crônica/mortalidade , Transplante de Rim/efeitos adversos , Mortalidade/tendências , Adulto , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Creatinina/metabolismo , Cistatina C/metabolismo , Método Duplo-Cego , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Imunossupressores/uso terapêutico , Falência Renal Crônica/cirurgia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Fatores de Risco , Taxa de Sobrevida , Microglobulina beta-2/metabolismo
2.
Diabetes Obes Metab ; 18(2): 169-77, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26511599

RESUMO

AIMS: To investigate whether the degree of albuminuria reduction observed in the ALTITUDE trial is associated with renal and cardiovascular protection, and secondly, whether the reduction in albuminuria was too small to afford clinical benefit. METHODS: In a post hoc analysis of the ALTITUDE trial in 8561 patients with type 2 diabetes and chronic kidney disease or cardiovascular disease we examined the effect of albuminuria changes at 6 months on renal and cardiovascular outcomes using Cox proportional hazard regression. RESULTS: The median change in albuminuria in the first 6 months in the aliskiren arm of the trial was -12% (25th to 75th percentile: -48.7_to_ +41.9%) and 0.0% (25th to 75th percentile: -40.2_to_55%) in the placebo arm. Changes in albuminuria in the first 6 months were linearly associated with renal and cardiovascular endpoints: a >30% reduction in albuminuria in the first 6 months was associated with a 62% reduction in renal risk and a 25% reduction in cardiovascular risk compared with an increase in albuminuria. The association between changes at 6 months in albuminuria and renal or cardiovascular endpoints was similar in the two treatment groups (p for interaction >0.1 for both endpoints). CONCLUSIONS: The addition of aliskiren to angiotensin-converting enzyme inhibitor/angiotensin receptor blocker therapy resulted in albuminuria changes that were associated with renal and cardiovascular risk changes. This did not translate into renal or cardiovascular protection because the overall reduction in albuminuria in the aliskiren arm was too small and nearly similar to that in the placebo arm.


Assuntos
Albuminúria/prevenção & controle , Anti-Hipertensivos/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Hipertensão/tratamento farmacológico , Insuficiência Renal Crônica/prevenção & controle , Renina/antagonistas & inibidores , Idoso , Albuminúria/complicações , Albuminúria/epidemiologia , Amidas/uso terapêutico , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Biomarcadores/urina , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Seguimentos , Fumaratos/uso terapêutico , Humanos , Hipertensão/complicações , Hipertensão/urina , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco
3.
Mucosal Immunol ; 6(2): 256-66, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22785226

RESUMO

Acute lung injury (ALI) is a severe illness with excess mortality and no specific therapy. Protective actions were recently uncovered for docosahexaenoic acid-derived mediators, including D-series resolvins. Here, we used a murine self-limited model of hydrochloric acid-induced ALI to determine the effects of aspirin-triggered resolvin D1 (AT-RvD1; 7S,8R,17R-trihydroxy-4Z,9E,11E,13Z,15E,19Z-docosahexaenoic acid) on mucosal injury. RvD1 and its receptor ALX/FPR2 were identified in murine lung after ALI. AT-RvD1 (~0.5-5 µg kg(-1)) decreased peak inflammation, including bronchoalveolar lavage fluid (BALF) neutrophils by ~75%. Animals treated with AT-RvD1 had improved epithelial and endothelial barrier integrity and decreased airway resistance concomitant with increased BALF epinephrine levels. AT-RvD1 inhibited neutrophil-platelet heterotypic interactions by downregulating both P-selectin and its ligand CD24. AT-RvD1 also significantly decreased levels of BALF pro-inflammatory cytokines, including interleukin (IL)-1ß, IL-6, Kupffer cells, and tumor necrosis factor-α, and decreased nuclear factor-κB-phosphorylated p65 nuclear translocation. Taken together, these findings indicate that AT-RvD1 displays potent mucosal protection and promotes catabasis after ALI.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Ácidos Docosa-Hexaenoicos/metabolismo , Inflamação/metabolismo , Mucosa Respiratória/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Resistência das Vias Respiratórias , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Plaquetas/metabolismo , Barreira Alveolocapilar/fisiopatologia , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/biossíntese , Epinefrina/metabolismo , Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Leucócitos/imunologia , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Neutrófilos/imunologia , Edema Pulmonar/imunologia , Edema Pulmonar/metabolismo , Edema Pulmonar/patologia , Receptores de Formil Peptídeo/metabolismo , Mucosa Respiratória/patologia , Fator de Transcrição RelA/metabolismo
4.
Qual Saf Health Care ; 19(5): 405-10, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20702441

RESUMO

OBJECTIVE: Recognition of learning curves in medical skill acquisition has enhanced patient safety through improved training techniques. Clinical trials research has not been similarly scrutinised. The VALsartan In Acute myocardial iNfarcTion, a large multinational, pragmatic, randomised, double-blind, multicentre trial, was retrospectively evaluated for evidence of research conduct consistent with a performance "learning curve". DESIGN: Records provided protocol departure (deviations/violations) and documentation query data. For each site, analysis included patient order (eg, first, second), recruitment rate and first enrollment relative to study start date. SETTING: Computerised data from a trial coordinated by an academic research organisation collaborating with 10 academic and 2 commercial research organisations and an industry sponsor. Interventions 931 sites enrolled 14,703 patients. Departures were restricted to the first year. Exclusions included patient's death or loss to follow-up within 12 months and subjects enrolled 80th or higher at a site. Departures were assessed for variance with higher patient rank, more frequent recruitment and later start date. METHODS AND RESULTS: 12,367 patients at 931 sites were analysed. Departures were more common for patients enrolled earlier at a site (p<0.0001). For example, compared with the 30th patient, the first had 47% more departures. Departures were also more common with slower enrollment and site start closer to the trial start date (p<0.0001). Similar patterns existed for queries. CONCLUSIONS: Research performance improved during the VALsartan In Acute myocardial iNfarcTion consistent with a "learning curve". Although effects were not related to a change in outcome (mortality), learning curves in clinical research may have important safety, ethical, research quality and economic implications for trial conduct.


Assuntos
Protocolos Clínicos , Fidelidade a Diretrizes , Curva de Aprendizado , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Estudos Multicêntricos como Assunto , Estudos Retrospectivos
5.
Mucosal Immunol ; 3(3): 270-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20130564

RESUMO

The widespread use of statins for hypercholesterolemia has uncovered pleiotropic anti-inflammatory properties that were unexpected based on the drugs' original design; yet, mechanisms for these protective actions remain uncertain. In this study lovastatin triggered biosynthesis of the anti-inflammatory and pro-resolving mediator 15-epi-lipoxin A(4) (15-epi-LXA(4)). During interactions between human neutrophils and airway epithelial cells, the statin-induced increase in 15-epi-LXA(4) was associated with increased 14,15-epoxyeicosatrienoic acid (14,15-EET) generation. When added to activated neutrophils, 14,15-EET enhanced 15-epi-LXA(4) biosynthesis. In a murine model of airway mucosal injury and inflammation, lovastatin increased 15-epi-LXA(4) formation in vivo and markedly decreased acute lung inflammation. Administration of 15-epi-LXA(4) also inhibited lung inflammation in an additive manner with lovastatin. Together, these results indicate that statin-triggered 15-epi-LXA(4) generation during human leukocyte-airway epithelial cell interactions is an endogenous mechanism for statin-mediated tissue protection at mucosal surfaces that may also be relevant in the statins' ability to stimulate the resolution of inflammation.


Assuntos
Anticolesterolemiantes/farmacologia , Mediadores da Inflamação/imunologia , Lipoxinas/imunologia , Lovastatina/farmacologia , Pneumonia/imunologia , Mucosa Respiratória/imunologia , Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Ácido 8,11,14-Eicosatrienoico/imunologia , Ácido 8,11,14-Eicosatrienoico/metabolismo , Doença Aguda , Animais , Linhagem Celular , Modelos Animais de Doenças , Feminino , Humanos , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/imunologia , Hipercolesterolemia/metabolismo , Inflamação/imunologia , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Lipoxinas/metabolismo , Masculino , Camundongos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Pneumonia/tratamento farmacológico , Pneumonia/metabolismo , Mucosa Respiratória/metabolismo
7.
Heart ; 93(1): 59-64, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16952975

RESUMO

BACKGROUND: Electrocardiographic left ventricular hypertrophy (ECG LVH) is a powerful independent predictor of cardiovascular morbidity and mortality in hypertension. OBJECTIVE: To determine the contemporary prevalence and prognostic implications of ECG LVH in a broad spectrum of patients with heart failure with and without reduced left ventricular ejection fraction (LVEF). METHODS AND OUTCOME: The Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) programme randomised 7599 patients with symptomatic heart failure to receive candesartan or placebo. The primary outcome comprised cardiovascular death or hospital admission for worsening heart failure. The relative risk (RR) conveyed by ECG LVH compared with a normal ECG was examined in a Cox model, adjusting for as many as 31 covariates of prognostic importance. RESULTS: The prevalence of ECG LVH was similar in all three CHARM trials (Alternative, 15.4%; Added, 17.1%; Preserved, 14.7%; Overall, 15.7%) despite a more frequent history of hypertension in CHARM-Preserved. ECG LVH was an independent predictor of worse prognosis in CHARM-Overall. RR for the primary outcome was 1.27 (95% confidence interval (CI) 1.04 to 1.55, p = 0.018). The risk of secondary end points was also increased: cardiovascular death, 1.50 (95% CI 1.13 to 1.99, p = 0.005); hospitalisation due to heart failure, 1.19 (95% CI 0.94 to 1.50, p = 0.148); and composite major cardiovascular events, 1.35 (95% CI 1.12 to 1.62, p = 0.002). CONCLUSION: ECG LVH is similarly prevalent in patients with symptomatic heart failure regardless of LVEF. The simple clinical finding of ECG LVH was an independent predictor of a worse clinical outcome in a broad spectrum of patients with heart failure receiving extensive contemporary treatment. Candesartan had similar benefits in patients with and without ECG LVH.


Assuntos
Insuficiência Cardíaca/etiologia , Hipertrofia Ventricular Esquerda/complicações , Idoso , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Benzimidazóis/uso terapêutico , Compostos de Bifenilo , Eletrocardiografia , Métodos Epidemiológicos , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Hipertrofia Ventricular Esquerda/epidemiologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Índice de Gravidade de Doença , Volume Sistólico , Tetrazóis/uso terapêutico , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia
8.
Clin Genet ; 61(1): 21-5, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11903350

RESUMO

The D/I (deletion, D, insertion, I) polymorphism of the angiotensin-converting enzyme (ACE) gene has been extensively studied for its association with a number of cardiovascular and other disease states. However, its potential association with differential clinical efficacy of ACE inhibitors (ACE-I) administered to patients who had suffered a myocardial infarction (MI), i.e. the prevention of left ventricular (LV) remodeling, has so far not been specifically studied. The aim of the study was to investigate whether the D/I polymorphism of the ACE gene is associated with the incidence of post-MI LV remodeling in patients drawn from the 'Healing and Early Afterload Reducing Therapy' (HEART) Study. The ACE D/I polymorphism was characterized by the polymerase chain reaction (PCR) in 265 subjects from the 'Healing and Early Afterload Reducing Therapy' Study, a double-blind, placebo-controlled trial with the objective of determining whether early or delayed administration of the ACE-I, ramipril, in patients with acute anterior wall MI would be optimal in reducing LV enlargement. Selected frequencies for the ACE D and I alleles were 0.59 and 0.41 (placebo-high dose group), 0.56 and 0.44 (low dose-low dose group), and, 0.60 and 0.40 (high dose-high dose group), respectively. All observed genotype frequencies were in Hardy-Weinberg equilibrium. There was no evidence for an association between genotype and outcome regarding LV size or function, nor with the initial blood pressure response after ACE-I administration (adjusted for covariates). Our data provide no evidence for an association of the ACE D/I polymorphism with the risk of LV remodeling post-MI in the presence of ACE-I therapy, and therefore do not suggest that differential clinical efficacy of ACE-inhibitors is related to this genetic marker.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Peptidil Dipeptidase A/genética , Polimorfismo Genético/genética , Remodelação Ventricular , Idoso , Método Duplo-Cego , Eletrocardiografia , Frequência do Gene , Marcadores Genéticos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/genética , Peptidil Dipeptidase A/metabolismo , Farmacogenética , Fenótipo , Ramipril/uso terapêutico , Resultado do Tratamento
9.
Hypertension ; 38(6): 1433-9, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11751731

RESUMO

Pulse pressure, an indirect measure of vascular stiffness and pulsatile load, predicts clinical events in congestive heart failure (CHF), suggesting that abnormal pulsatile load may contribute to CHF. This study was designed to assess more direct measures of central pulsatile load in CHF. Noninvasive hemodynamic evaluations were performed in 28 subjects with CHF and 40 controls using calibrated tonometry of the brachial, radial, femoral, and carotid arteries along with echocardiographic assessment of left ventricular outflow tract (LVOT) diameter and Doppler flow. Characteristic impedance (Z(c)) was calculated as the ratio of DeltaP (carotid) and DeltaQ (LVOT flow) in early systole. Carotid-radial (CR-PWV) and carotid-femoral (CF-PWV) pulse wave velocities were calculated from tonometry. Augmentation index was assessed from the carotid waveform. Total arterial compliance (TAC) was calculated using the area method. Brachial pulse pressure was elevated (62+/-16 versus 53+/-15 mm Hg, P=0.015) in CHF because of lower diastolic pressure (66+/-10 versus 73+/-9 mm Hg, P=0.003). CHF had higher Z(c) (225+/-76 versus 184+/-66 dyne. sec. cm(-5), P=0.020). CF-PWV did not differ (9.7+/-2.7 versus 9.2+/-2.0, P=0.337), whereas CR-PWV was lower in CHF (8.6+/-1.4 versus 9.4+/-1.5, P=0.038). There was no difference in TAC (1.4+/-0.5 versus 1.4+/-0.6 mL/mmHg, P=0.685), and augmentation index was lower in CHF (8+/-17 versus 21+/-13%, P=0.001). CHF subjects have elevated central pulsatile load (Z(c)), which is not apparent in global measures such as augmentation index or TAC, possibly because of contrasting changes in central and peripheral conduit vessels. This increased pulsatile load represents an important therapeutic target in CHF.


Assuntos
Artérias/fisiopatologia , Proteínas da Matriz Extracelular , Insuficiência Cardíaca/fisiopatologia , Fluxo Pulsátil , Velocidade do Fluxo Sanguíneo , Artérias Carótidas/diagnóstico por imagem , Proteínas Contráteis , Método Duplo-Cego , Elasticidade , Eletrocardiografia , Feminino , Insuficiência Cardíaca/complicações , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Processamento de RNA , Ultrassonografia , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/fisiopatologia
11.
Tex Heart Inst J ; 28(3): 239, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11678269
13.
Am J Cardiol ; 88(4): 347-52, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11545752

RESUMO

Chromosome 17q21-23 harbors genes for platelet glycoprotein IIIa and angiotensin-converting enzyme (ACE), which are polymorphic for alleles Pl(A2) and ACE "D." These alleles have been independently and often associated with ischemic coronary artery disease (CAD). We sought to determine if the Pl(A2) and ACE D polymorphisms were risk factors for recurrent coronary events. In the Cholesterol And Recurrent Events (CARE) trial, 4,159 men and women with documented myocardial infarction (MI) were randomized to receive either placebo or pravastatin, and were followed prospectively for 5 years. Pl(A) and ACE genotypes were determined in 767 patients: 385 cases who had experienced a recurrent primary event (death due to coronary disease or nonfatal MI), and 382 age- and gender-matched controls. In patients receiving placebo, the Pl(A1,A2) genotype conferred a relative risk (RR) of 1.38 (confidence intervals [CI] 1.04 to 1.83; p = 0.028; adjusted RR = 1.32, CI = 0.99 to 1.76; p = 0.058]) for the primary end point. Compared with the placebo group, pravastatin reduced the excess RR of coronary disease death and recurrent MI in the Pl(A1,A2) patient population by 31% (p = 0.06). The ACE D allele appeared to have modestly additive effects on the Pl(A1,A2) risk. Among the Pl(A1,A2) patients, pravastatin had little effect on the risk of recurrent events with the ACE II genotype, but reduced the adjusted RR from 1.42 (placebo) to 0.58 for ACE ID patients, and from 1.56 (placebo) to 0.83 for ACE DD. The Pl(A1,A2) genotype was associated with an excess of recurrent coronary events in patients after MI who did not receive pravastatin, and the ACE D allele added to this risk. These data suggest that it would be important to perform a larger study to address the potential role of these genotypes in therapeutic decision making.


Assuntos
Infarto do Miocárdio/genética , Peptidil Dipeptidase A/genética , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/genética , Idoso , Alelos , Anticolesterolemiantes/uso terapêutico , Feminino , Deleção de Genes , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Polimorfismo Genético , Pravastatina/uso terapêutico , Isoformas de Proteínas , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Fatores de Risco
14.
Cardiovasc Drugs Ther ; 15(1): 11-3, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11504157

RESUMO

Impressive clinical benefits have been derived by inhibiting the renin-angiotensin-aldosterone system with angiotensin-converting enzyme inhibitors. There is growing evidence that aldosterone plays a contributing role in the pathogenesis of heart failure beyond its sodium retention properties. EPHESUS, a trial of a novel aldosterone antagonist, eplerenone, in patients with myocardial infarction, left ventricular dysfunction and pulmonary congestion will determine whether this approach produces additive clinical benefits in modernly managed patients.


Assuntos
Aldosterona/fisiologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Sistema Renina-Angiotensina/efeitos dos fármacos , Espironolactona/análogos & derivados , Espironolactona/uso terapêutico , Ensaios Clínicos como Assunto , Eplerenona , Humanos , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico
16.
Clin Cardiol ; 24(7 Suppl): II-18, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11444650

RESUMO

Despite a totality of evidence indicating clear benefits of statin therapy in secondary and primary prevention of cardiovascular disease (CVD), a large number of additional trials are currently planned or in progress to help us better understand, treat, and prevent CVD. Both monotherapy and combination statin regimens are being studied to optimize treatment of the total patient and to assess mechanisms and benefits of various components of the total lipid profile.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipolipemiantes/uso terapêutico , Humanos
17.
Hypertension ; 37(5): 1222-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11358932

RESUMO

The role of mitogen-activated protein kinase (MAPK) pathways as signal transduction intermediates of hemodynamic stress leading to cardiac hypertrophy in the adult heart is not fully established. In a rat model of pressure-overload hypertrophy, we examined whether activation of MAPK pathways, namely, the extracellular signal-regulated protein kinase (ERK), c-Jun NH(2)-terminal kinase (JNK), and the p38-MAPK pathways, occurs during rapid changes in hemodynamic load in vivo. A slight activation of ERK2 and marked increases in JNK1 and p38-MAPK activities were observed 30 minutes after aortic banding. The increase in p38-MAPK activity was accompanied by an increase in the phosphorylation of the p38 substrate MAPK-activated protein kinases 2 and 3. Activation of these kinases was coincident with an increase in phosphorylation of c-Jun and activating transcription factor-2 (ATF-2) and enhanced DNA binding of activator protein-1 factors. Thus, hemodynamic stress of the adult rat heart in vivo results in rapid activation of several parallel MAPK kinase cascades, particularly stress-activated MAPK and p38-MAPK and their target transcription factors c-Jun and ATF-2.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Miocárdio/enzimologia , Estresse Fisiológico/enzimologia , Fator 2 Ativador da Transcrição , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Modelos Animais de Doenças , Ativação Enzimática , Feminino , Proteínas Quinases JNK Ativadas por Mitógeno , Miocárdio/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-jun/metabolismo , Ratos , Ratos Wistar , Estresse Fisiológico/fisiopatologia , Fator de Transcrição AP-1/metabolismo , Fatores de Transcrição/metabolismo , Função Ventricular Esquerda/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno
18.
Ann Intern Med ; 134(6): 451-8, 2001 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-11255520

RESUMO

BACKGROUND: Patients with reduced left ventricular function and ventricular enlargement after myocardial infarction are at significantly greater risk for congestive heart failure and death. Nevertheless, recovery of ventricular function occurs in a significant proportion of patients after myocardial infarction, and modern reperfusion strategies have been associated with increased recovery of function. OBJECTIVE: To determine the extent and predictors of recovery of ventricular function after anterior Q-wave myocardial infarction in the reperfusion era. DESIGN: Subgroup analysis of the Healing and Early Afterload Reducing Therapy study. SETTING: 35 medical centers in the United States and Canada. PATIENTS: 352 patients with Q-wave anterior myocardial infarction. INTERVENTION: Placebo for 14 days, followed by full-dose (10 mg) ramipril until day 90; low-dose (0.625 mg) ramipril for 90 days; or full-dose ramipril for 90 days. All patients underwent reperfusion therapy. MEASUREMENTS: Echocardiography was performed on day 1 (before randomization), day 14, and day 90 after myocardial infarction. Left ventricular volume and ejection fraction were measured and wall-motion analyses were performed at all three time points in 249 patients and at baseline in an additional 12 patients who died during follow-up. Echocardiographic and nonechocardiographic predictors of ventricular recovery were examined. RESULTS: By day 90, 55 of 252 (22%) patients who had abnormal ejection fraction and wall-motion abnormalities on day 1 demonstrated complete recovery of function (ejection fraction in the normal range and infarct segment length of 0%), and an additional 36% (91 of 252 patients) demonstrated partial recovery of function. At 90 days, 53% (132 of 249) of patients had greater than 5% improvement in ejection fraction, whereas only 16% (39 of 249) had a decrease in ejection fraction of more than 5%. The majority of functional improvement occurred by day 14 after infarction. Of various clinical and echocardiographic measures obtained on day 1, peak creatine kinase level was the strongest independent predictor of subsequent recovery of ventricular function in multivariate analysis. Each 100-unit increase in peak creatine kinase was associated with a 4.3% decreased odds of recovery (P < 0.001) after adjustment for ejection fraction on day 1, extent of akinesis or dyskinesis, treatment regimen, Killip class, age, and sex. CONCLUSION: Significant myocardial stunning with subsequent improvement of ventricular function occurred in the majority of patients after Q-wave anterior myocardial infarction. A lower peak level of creatine kinase, an estimate of the extent of necrosis, is independently predictive of recovery of function. Early functional assessment (day 1 after acute myocardial infarction) had limited ability to predict recovery of ventricular function.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Cardiomegalia/complicações , Cardiomegalia/terapia , Infarto do Miocárdio/complicações , Reperfusão Miocárdica , Ramipril/uso terapêutico , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/terapia , Cardiomegalia/cirurgia , Creatina Quinase/metabolismo , Método Duplo-Cego , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Recuperação de Função Fisiológica , Fatores de Risco , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem
19.
Am Heart J ; 141(2): 234-42, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11174337

RESUMO

BACKGROUND: Increased left ventricular (LV) wall stress after myocardial infarction (MI) has been implicated in LV remodeling. However, the relationship between LV wall stress and LV remodeling is incompletely defined. METHOD: We prospectively studied the relationship between regional wall stress and LV remodeling by application of the finite element method to end-systolic LV models from patients enrolled in the Healing and Early Afterload Reducing Therapy (HEART) Trial. Individual LV models were constructed from orthogonal apical echocardiographic views obtained at day 14 after anteroseptal MI in 64 patients. Of these, 31 patients received low-dose (0.625 mg) ramipril and 33 patients received full-dose (10 mg) ramipril. LV wall stress was calculated by the finite element method and correlated with change in LV volume from day 14 to day 90 after MI. RESULTS: Among all patients, increases in apical regional wall stress were associated with LV volume changes (P -trend =.015). The relationship between apical regional wall stress and change in LV volume was strongest in the low-dose ramipril group (r = 0.53, P =.002) and remained significant after adjustment for end-diastolic volume, infarct size, ejection fraction, and systolic blood pressure yet was attenuated in the full-dose ramipril group. CONCLUSIONS: Apical regional wall stress is an independent predictor of subsequent LV remodeling after MI. The relationship between increased apical wall stress and LV dilatation appears to be attenuated by full-dose angiotensin-converting enzyme inhibition.


Assuntos
Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Infarto do Miocárdio/fisiopatologia , Estresse Fisiológico/fisiopatologia , Remodelação Ventricular , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Feminino , Análise de Elementos Finitos , Septos Cardíacos , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/efeitos dos fármacos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/tratamento farmacológico , Prognóstico , Estudos Prospectivos , Ramipril/uso terapêutico , Segurança , Estresse Fisiológico/complicações , Estresse Fisiológico/tratamento farmacológico , Volume Sistólico/efeitos dos fármacos , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/prevenção & controle , Remodelação Ventricular/efeitos dos fármacos
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