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1.
Artículo en Alemán | MEDLINE | ID: mdl-18330670

RESUMEN

In patients with frequent right ventricular stimulation, worsening of heart failure and atrial fibrillation may occur. Avoidance of unnecessary right ventricular pacing is a major requirement for pacemaker selection and programming in patients with sinus node disease or intermittent AV block. In dual chamber pacemakers this goal can be achieved by programming a long AV delay or an AV delay hysteresis. Algorithms that allow AAI pacing in a dual chamber pacing mode and change to DDD mode in case of high degree AV block are a new attempt to avoid unnecessary right ventricular pacing. The article describes various strategies to avoid unnecessary ventricular pacing and discusses their advantages and disadvantages.


Asunto(s)
Bloqueo Atrioventricular/terapia , Estimulación Cardíaca Artificial , Marcapaso Artificial , Síndrome del Seno Enfermo/terapia , Algoritmos , Bloqueo Atrioventricular/fisiopatología , Contraindicaciones , Electrocardiografía , Atrios Cardíacos/fisiopatología , Ventrículos Cardíacos/fisiopatología , Humanos , Diseño de Prótesis , Síndrome del Seno Enfermo/fisiopatología , Programas Informáticos
2.
Circulation ; 102(2): 211-7, 2000 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-10889133

RESUMEN

BACKGROUND: Cardiac troponin T (cTnT) is a sensitive and specific marker, allowing the detection of even minor myocardial cell injury. In patients with severe pulmonary embolism (PE), myocardial ischemia may lead to progressive right ventricular dysfunction. It was therefore the purpose of this study to test the presence of cTnT and its prognostic implications in patients with confirmed PE. METHODS AND RESULTS: Fifty-six consecutive patients with confirmed PE were enrolled in this prospective study. PE was confirmed by pulmonary angiography, lung scan, or echocardiography and subsidiary analyses. Severity of PE was assessed by a clinical scoring system, and cTnT was measured within 12 hours after admission. cTnT was elevated (>/=0.1 microg/L) in 18 (32%) patients with massive and moderate PE but not in patients with small PE. In-hospital death (odds ratio 29. 6, 95% CI 3.3 to 265.3), prolonged hypotension and cardiogenic shock (odds ratio 11.4, 95% CI 2.1 to 63.4), and need for resuscitation (odds ratio 18.0, 95% CI 2.6 to 124.3) were more prevalent in patients with elevated cTnT. cTnT-positive patients more often needed inotropic support (odds ratio 37.6, 95% CI 5.8 to 245.6) and mechanical ventilation (odds ratio 78.8, 95% CI 9.5 to 653.2). After adjustment, cTnT remained an independent predictor of 30-day mortality (odds ratio 15.2, 95% CI 1.22 to 190.4). CONCLUSIONS: cTnT may improve risk stratification in patients with PE and may aid in the identification of patients in whom a more aggressive therapy may be warranted.


Asunto(s)
Enfermedad Coronaria/sangre , Enfermedad Coronaria/diagnóstico , Embolia Pulmonar/sangre , Embolia Pulmonar/diagnóstico , Troponina T/sangre , Anciano , Biomarcadores , Enfermedad Coronaria/mortalidad , Femenino , Mortalidad Hospitalaria , Hospitalización , Humanos , Incidencia , Masculino , Isquemia Miocárdica/sangre , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/mortalidad , Valor Predictivo de las Pruebas , Pronóstico , Embolia Pulmonar/mortalidad , Factores de Riesgo
3.
Circulation ; 104(6): 630-5, 2001 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-11489766

RESUMEN

BACKGROUND: In ST-segment elevation myocardial infarction, a troponin T >/=0.1 microg/L on admission indicates poorer prognosis despite early reperfusion. To evaluate the underlying reason, we studied the value of cardiac troponin T (cTnT) for prediction of outcomes, epicardial blood flow, and myocardial reperfusion after primary percutaneous intervention. METHODS AND RESULTS: Patients (n=140) admitted within 12 hours after onset of symptoms were stratified by admission cTnT. Epicardial and myocardial reperfusion were graded by the TIMI score and by measurement of relative increases of myoglobin, cTnT, and creatine kinase (CK)-MB 60 minutes after recanalization, respectively. cTnT was positive in 64 patients (45.7%) and was associated with longer median time intervals to admission (5.5 versus 3.5 hours, P<0.001) and higher mortality rates after 30 days (12.5% versus 3.9%, P=0.06) and 9 months (14% versus 3.9%, P=0.005). cTnT independently predicted a 3.2-fold risk for incomplete epicardial reperfusion (P=0.03). In addition, cTnT >/=0.1 microg/L was associated with more severely impaired myocardial perfusion despite normal epicardial flow, as indicated by lower 60-minute ratios of myoglobin (2.6 versus 7.6, P=0.007), cTnT (6.6 versus 29.2, P<0.001), and CK-MB (3.5 versus 21.4, P=0.002) and a tendency for less resolution of ST-segment elevations (54% versus 60%, P=0.08). CONCLUSIONS: cTnT predicts poorer clinical outcomes, lower rates of postprocedural TIMI 3 flow, and more severely compromised myocardial perfusion despite normal epicardial flow. Thus, a cTnT-positive patient may require more aggressive adjunctive therapy when treated by percutaneous coronary intervention. The impact of preexisting or evolving microvascular dysfunction and the effect of therapies that target myocardial perfusion require further prospective evaluation.


Asunto(s)
Circulación Coronaria , Infarto del Miocardio/terapia , Troponina/sangre , Anciano , Angioplastia Coronaria con Balón , Biomarcadores/sangre , Estudios de Cohortes , Creatina Quinasa/sangre , Forma MB de la Creatina-Quinasa , Femenino , Humanos , Isoenzimas/sangre , Masculino , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/sangre , Infarto del Miocardio/patología , Daño por Reperfusión Miocárdica/fisiopatología , Mioglobina/sangre , Admisión del Paciente , Valor Predictivo de las Pruebas , Pronóstico , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
4.
Circulation ; 102(17): 2038-44, 2000 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-11044417

RESUMEN

BACKGROUND: Cardiac troponin T (cTnT) elevations on admission indicate a high-risk subgroup of patients with ST-segment elevation acute myocardial infarction (AMI). This finding has been attributed to less effective reperfusion after thrombolytic therapy. The aim of this study was to determine the role of admission cTnT on the efficacy of percutaneous coronary interventions (PCIs) in inferior AMI. METHODS AND RESULTS: One hundred fifty-nine consecutive patients with inferior ST-segment AMI were enrolled and followed up for a mean of 448 days. Patients were stratified by cTnT on admission. A cTnT >/=0.1 microg/L was found in 58% of patients. These patients had longer time intervals from onset of symptoms to therapy (P:<0. 001) and higher 30-day (10.8% versus 1.5%, P:=0.027) and long-term (17.2% versus 4.5%, P:=0.023) cardiac mortalities. Rates of the combined end point of death, nonfatal reinfarction, and need for repeated target vessel revascularization procedures were not different in cTnT groups (log rank, 0.69; P:=0.41). PCI was attempted in 93.3% of cTnT-positive and 98.5% cTnT-negative patients (P:=0.24) but was less frequently successful in patients with cTnT >/=0.1 microg/L (77.9% versus 96.9%, P:<0.001). Coronary stenting reduced 30-day and long-term cardiac mortality, particularly among cTnT-positive patients. In a multivariate analysis, cTnT indicated an approximately 5-fold-higher risk (adjusted OR, 4.6; 95% CI, 0.79 to 27.11; P:=0.089) and was a strong albeit not independent risk predictor. CONCLUSIONS: In inferior AMI, a positive admission cTnT is associated with lower success rates of direct PCI and higher rates of cardiac events over the short and long term. These patients benefit from coronary stenting.


Asunto(s)
Infarto del Miocardio/metabolismo , Troponina T/metabolismo , Enfermedad Aguda , Anciano , Angiografía Coronaria , Electrocardiografía , Femenino , Humanos , Masculino , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/terapia , Evaluación de Resultado en la Atención de Salud , Medición de Riesgo , Stents
5.
Cell Death Differ ; 8(7): 734-46, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11464218

RESUMEN

Phagocytosis of apoptotic cells is required to prevent tissue injury. Professional phagocytes, such as monocyte-derived macrophages, are highly efficient scavengers of apoptotic cells but their presence cannot always be relied on; in that case, removal of effete cells is accomplished by helpful neighbours. This study describes differences in the efficiency with which apoptotic cells of the same type, but dying in response to different triggers, are engulfed; this varies from engulfment that is so proficient few or no unengulfed apoptotic cells are found, to engulfment that is so delayed apoptotic cells have become secondarily necrotic at the point of engulfment. In all cases the efficiency of engulfment is determined at least in part by the dying cells themselves. p53- and Bax-transfected kidney epithelial (293) cells (transiently transfected using a non-toxic method) were engulfed so proficiently by homotypic neighbours that cells did not show evidence of engagement of the apoptotic programme (chromatin condensation and TUNEL positivity) until engulfment had taken place. Engulfment nonetheless required activation of at least initiator caspases. 293 cells induced to apoptose by other means (etoposide and staurosporine treatment) were not so efficiently ingested: unengulfed apoptotic cells were consistently revealed at all doses and time points, even when treated cells were mixed with healthy, non-treated 293 cells. These data make it extremely unlikely that the fraction of viable, unaffected neighbours determines the efficiency with which engulfment proceeds. Furthermore, 293 cells treated with etoposide or staurosporine were differentially appealing both to homotypic neighbours and to cells in the professional phagocyte lineage (THP-1 cells). If different apoptotic stimuli programme cells to be recognised with different efficiencies, pathways to apoptosis may be injury limiting to greater or lesser degrees.


Asunto(s)
Apoptosis , Fagocitos/fisiología , Fagocitosis , Proteínas Proto-Oncogénicas c-bcl-2 , Proteínas Proto-Oncogénicas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Línea Celular , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Etopósido/farmacología , Humanos , Microscopía Fluorescente , Mutación , Necrosis , Especificidad de Órganos , Fagocitos/citología , Fagocitos/efectos de los fármacos , Fagocitos/metabolismo , Fagocitosis/efectos de los fármacos , Estaurosporina/farmacología , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/genética , Proteína X Asociada a bcl-2
6.
J Am Coll Cardiol ; 37(1): 44-50, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11153771

RESUMEN

OBJECTIVES: The aim of this study was to determine the influence of early reperfusion on the course of QT interval and QT interval variability in patients undergoing primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) and its prognostic implications on major arrhythmic events during one-year follow-up. BACKGROUND: Although early coronary artery recanalization by primary angioplasty is an established therapy in AMI, a substantial number of patients is still threatened by malignant arrhythmias even after early successful reperfusion, which may be caused by an inhomogeneity of ventricular repolarization despite reperfusion. METHOD: Temporal fluctuations of ventricular repolarization were studied prospectively in 97 consecutive patients with a first AMI by measurements of QT interval and QT interval variability during and after successful PTCA (Thrombolysis in Myocardial Infarction flow grades 2 and 3). Continuous beat-to-beat QT interval measurement was performed from 24-h Holter monitoring, which was initiated at admission before PTCA. RESULTS: Reperfusion caused a significant continuous increase of mean RR interval (738 +/- 98 to 808.5 +/- 121 ms; p < 0.001) and a significant decrease of parameters of QT interval (QTc: 440 +/- 32 to 416.5 +/- 37ms; p < 0.001) and QT interval variability (QTcSD: 27.5 +/- 3 to 24.9 +/- 6 ms; p < 0.001) in the majority of patients. However, in patients with major arrhythmic events at the one-year follow-up (sudden cardiac death, ventricular fibrillation or sustained ventricular tachycardia, n = 15), parameters of QT interval remained unaltered after successful reperfusion (QTc: 447.3 +/- 41 to 432.9 +/- 45 ms, p = NS; QTcSD: 35.1 +/- 13.4 to 29.0 +/- 9.1 ms, p = NS). CONCLUSIONS: Reduction of QT interval and QT interval variability after timely reperfusion of the infarct-related artery may be a previously unreported beneficial mechanism of primary PTCA in AMI, indicating successful reperfusion.


Asunto(s)
Angioplastia Coronaria con Balón , Electrocardiografía Ambulatoria , Síndrome de QT Prolongado/diagnóstico , Infarto del Miocardio/terapia , Daño por Reperfusión Miocárdica/diagnóstico , Anciano , Femenino , Estudios de Seguimiento , Humanos , Síndrome de QT Prolongado/mortalidad , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/mortalidad , Daño por Reperfusión Miocárdica/terapia , Tasa de Supervivencia , Resultado del Tratamiento
7.
Genetics ; 154(4): 1721-33, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10747065

RESUMEN

Proliferating cell nuclear antigen (PCNA) functions in DNA replication as a processivity factor for polymerases delta and epsilon, and in multiple DNA repair processes. We describe two temperature-sensitive lethal alleles (mus209(B1) and mus209(2735)) of the Drosophila PCNA gene that, at temperatures permissive for growth, result in hypersensitivity to DNA-damaging agents, suppression of position-effect variegation, and female sterility in which ovaries are underdeveloped and do not produce eggs. We show by mosaic analysis that the sterility of mus209(B1) is partly due to a failure of germ-line cells to proliferate. Strikingly, mus209(B1) and mus209(2735) interact to restore partial fertility to heteroallelic females, revealing additional roles for PCNA in ovarian development, meiotic recombination, and embryogenesis. We further show that, although mus209(B1) and mus209(2735) homozygotes are each defective in repair of transposase-induced DNA double-strand breaks in somatic cells, this defect is substantially reversed in the heteroallelic mutant genotype. These novel mutations map to adjacent sites on the three-dimensional structure of PCNA, which was unexpected in the context of this observed interallelic complementation. These mutations, as well as four others we describe, reveal new relationships between the structure and function of PCNA.


Asunto(s)
Drosophila melanogaster/genética , Genes Letales , Mutación , Antígeno Nuclear de Célula en Proliferación/genética , Alelos , Animales , Biopolímeros , División Celular/genética , Frío , Intercambio Genético , Reparación del ADN/genética , Femenino , Células Germinativas , Heterocigoto , Infertilidad Femenina/genética , Masculino , Meiosis/genética , Modelos Moleculares , Antígeno Nuclear de Célula en Proliferación/química , Temperatura
8.
Clin Pharmacol Ther ; 27(3): 297-300, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7357788

RESUMEN

The protein binding of phenytoin, propranolol, salicylic acid, warfarin, and bilirubin was determined in heparinized plasma and serum obtained from the same healthy adult subjects. There were no significant differences in the free fraction values of these compounds in plasma and serum. Addition of heparin to serum had no significant effect on protein binding. Contact with Vacutainer stoppers increased the free fraction of the weak base propranolol in serum and plasma but no significant effect on the protein binding of the other, weakly acidic compounds tested. The lack of differences in the protein binding of phenytoin, salicylic acid, warfarin, and bilirubin in human plasma and serum is in contrast with the pronounced differences observed previously in rat serum and plasma.


Asunto(s)
Bilirrubina/sangre , Fenitoína/sangre , Plastificantes/farmacología , Propranolol/sangre , Salicilatos/sangre , Warfarina/sangre , Adulto , Femenino , Heparina/farmacología , Humanos , Punto Isoeléctrico , Masculino , Unión Proteica/efectos de los fármacos
9.
Clin Pharmacol Ther ; 34(6): 770-6, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6641092

RESUMEN

Alinidine--N-allyl-clonidine--reduces heart rate without blocking beta adrenoreceptors. It may be used in patients with angina without inducing the adverse effects of beta-adrenergic blockers. We therefore evaluated alinidine efficacy in patients with angiographically proven coronary artery disease and stable angina during a 10-wk placebo-controlled randomized double-blind trial. Alinidine (40 mg three times a day) reduced the number of anginal attacks and the average number of nitroglycerine capsules consumed. The double product was slightly lowered during rest but more pronounced during exercise. This effect was mainly due to decreased heart rate. The ischemic S-T segment depression was diminished. Exercise tolerance was clearly improved in six, slightly improved in two, and unchanged in four subjects.


Asunto(s)
Angina de Pecho/tratamiento farmacológico , Clonidina/análogos & derivados , Adulto , Presión Sanguínea/efectos de los fármacos , Clonidina/farmacología , Clonidina/uso terapéutico , Método Doble Ciego , Evaluación de Medicamentos , Electrocardiografía , Prueba de Esfuerzo , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Distribución Aleatoria
10.
Clin Pharmacol Ther ; 33(6): 747-56, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6851405

RESUMEN

Isosorbide dinitrate (ISDN) kinetics and dynamics were examined after various routes of administration for angina. Given intravenously, ISDN kinetics were apparently linear over the range of infusion rate (0.083 and 0.133 mg/min) and duration (15 min and 1 and 2 hr) studied. Mean +/- SD systemic clearance of ISDN was 3.4 +/- 1.4 l/min and volume of distribution (VdSS or Vdarea) about 100 l. These data are consistent with the presence of extensive extrahepatic metabolism. In six patients, sublingual ISDN (5 mg) was also given and mean bioavailability of 59% (19% to 93%) for this route was determined. For this group, sublingual absorption of intact ISDN was incomplete and variable. The presence of a longer disappearance t 1/2 after sublingual dosing suggested that the input process may be rate limiting. After percutaneous application of a topical formulation (100 mg over an area of 400 cm2), steady-state plasma concentrations at about 7 ng/ml were maintained from 6 to 24 hr. The bioavailability of the topical application was estimated at 30%. At the doses given, intravenous ISDN had no apparent effect on heart rate but induced significant reduction in standing systolic blood pressure. The effect vs the ISDN concentration profile was described by a hysteresis loop, indicating that changes in blood pressure response lag behind changes in plasma ISDN concentration. After intravenous dosing, peak plasma ISDN concentration and peak effect (maximum change in standing systolic blood pressure). At the doses used, both sublingual and percutaneous ISDN induced less distinct circulatory changes than the intravenous infusion.


Asunto(s)
Dinitrato de Isosorbide/metabolismo , Absorción , Administración Oral , Administración Tópica , Adulto , Anciano , Angina de Pecho/tratamiento farmacológico , Disponibilidad Biológica , Presión Sanguínea/efectos de los fármacos , Femenino , Humanos , Infusiones Parenterales , Dinitrato de Isosorbide/administración & dosificación , Cinética , Masculino , Persona de Mediana Edad
11.
Clin Pharmacol Ther ; 34(6): 724-31, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6641086

RESUMEN

Hepatic extraction of organic nitrates, including that of isosorbide dinitrate (ISDN), has been thought to be nearly complete in man but has never been directly measured. We examined the time course of plasma ISDN and metabolite concentrations in arterial and hepatic venous blood in four cardiac patients receiving an intravenous ISDN infusion. Apparent hepatic extraction of ISDN was high (90%) at the beginning of infusion but fell to about 44% 1 hr after termination of infusion. The decrease in ISDN concentration gradient across the liver correlates with an increase in plasma isosorbide-5-mononitrate concentration, but a cause-and-effect relationship resulting from metabolite inhibition cannot be established. The time-averaged hepatic extraction of ISDN, at about 70%, agreed with its oral bioavailability in patients.


Asunto(s)
Enfermedad Coronaria/metabolismo , Dinitrato de Isosorbide/metabolismo , Hígado/metabolismo , Disponibilidad Biológica , Humanos , Infusiones Parenterales , Dinitrato de Isosorbide/sangre , Cinética , Masculino , Persona de Mediana Edad
12.
Gene ; 110(2): 181-7, 1992 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-1537555

RESUMEN

Serine proteases (SPs) are a family of physiologically important and versatile enzymes. We designed degenerated oligodeoxyribonucleotide primers derived from the consensus amino acid aa sequences of the active site of mammalian SPs, to selectively amplify in a polymerase chain reaction (PCR) cDNA fragments coding for SPs. We used poly(A)+ RNA from rat pancreas to obtain the cDNA. Two of the amplified cDNA fragments encode novel SPs. The full-length nucleotide sequence of both cDNAs was also obtained by PCR. The high degree of homology to trypsins and elastases suggests that the cDNAs encode a trypsin-like and an elastase-like SP, respectively. Both mRNAs were also found to occur, to a lesser extent, in spleen, as was the case for the mRNAs of other rat pancreatic SPs.


Asunto(s)
Páncreas/enzimología , Elastasa Pancreática/genética , Tripsina/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Clonación Molecular , Expresión Génica , Datos de Secuencia Molecular , Elastasa Pancreática/química , Reacción en Cadena de la Polimerasa , Ratas , Homología de Secuencia de Ácido Nucleico , Tripsina/química
13.
Gene ; 136(1-2): 167-75, 1993 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-8294000

RESUMEN

We designed degenerated oligodeoxyribonucleotide primers derived from amino acid (aa) sequences of the highly conserved active sites of mammalian serine proteases (SPs). These primers were used to selectively amplify, in polymerase chain reactions (PCRs), cDNA fragments coding for a SP. We used poly(A)+RNA from human brain to obtain cDNA fragments and amplified one cDNA encoding a novel SP. The full-length nucleotide (nt) sequence was identified by PCR and screening a genomic library in order to obtain the 5'-region. The deduced as sequence shows a high degree of homology to trypsinogens, except for the first exon. In addition to this brain-specific trypsinogen, there exists a variant of the cDNA in pancreas, differing only in the nt sequence of the first exon. An active form of the trypsin was synthesized in vitro and purified by affinity chromatography using soybean trypsin inhibitor (STI) agarose to demonstrate the trypsin-specific interaction with a naturally occurring inhibitor of trypsins.


Asunto(s)
Encéfalo/enzimología , Tripsinógeno/genética , Secuencia de Aminoácidos , Precursor de Proteína beta-Amiloide/metabolismo , Secuencia de Bases , Cromatografía de Afinidad , Clonación Molecular , Codón , Cartilla de ADN , ADN Complementario , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Biosíntesis de Proteínas , ARN Mensajero/genética , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Transcripción Genética , Tripsina/genética , Tripsina/aislamiento & purificación , Tripsinógeno/metabolismo
14.
Am J Med ; 87(6B): 45S-49S, 1989 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-2532460

RESUMEN

In clinical pharmacology studies cilazapril, after its bioactivation to cilazaprilat, was characterized as a potent, reversible angiotensin-converting enzyme (ACE) inhibitor with a terminal half-life of 30 to 50 hours consistent with saturable binding to ACE. Despite the arterial vasodilation, only slight increases in heart rate were found. Cilazapril had no acute effect on cardiovascular reflexes. Cilazapril increased effective renal plasma flow slightly. Glomerular filtration rate remained unaltered. A close and steep correlation between cilazaprilat plasma concentration and ACE inhibition was found. The potency of cilazaprilat, defined as the concentration of cilazaprilat causing 50 percent ACE inhibition, was approximately 1 ng/ml plasma. In short-term studies in hypertensive patients, it appeared that more than 90 percent of plasma ACE inhibition is needed to obtain blood pressure reduction. The result of various dose-response studies established the indirect relationship between dose, plasma concentration of the drug, and the blood pressure response and identified the dose producing maximal effect (i.e., 5 mg). Cilazapril had relatively long-lasting effects on ACE inhibition. In patients with severe chronic renal impairment or hepatic failure, the duration of ACE inhibition of cilazapril was prolonged. In these patients a reduction of the dose and/or less frequent dosing is recommended. There was no clinically relevant interaction of cilazapril with food or furosemide. The effects of hydrochlorothiazide on sodium and chloride excretion were potentiated by cilazapril. An additive effect of propranolol and nitrendipine on the blood pressure response to cilazapril was observed. An interaction with nonsteroidal anti-inflammatory drugs and cilazapril might occur, potentially reducing the blood pressure lowering effect. In general cilazapril was well tolerated.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Piridazinas/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacocinética , Cilazapril , Humanos , Piridazinas/farmacocinética
15.
Thromb Haemost ; 83(2): 224-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10739377

RESUMEN

OBJECTIVE: The present study sought to determine the incidence of increased procoagulant activity in patients with unstable angina (UAP), and to evaluate the relationship between cardiac troponin T (cTnT) and molecular markers of hemostatic activation. Method. We studied 44 patients with UAP further classified by plasma cTnT levels. All patients received an antithrombotic therapy consisting of therapeutic doses of unfractionated heparin and acetylsalicylic acid. Quantitative levels of cTnT and plasma concentrations of fibrin monomers (FM), prothrombin fragments F1+2, thrombin antithrombin III complexes (TAT), plasminogen and alpha2-antiplasmin were sampled serially within the first 48 h. RESULTS: Increased plasma concentrations of FM were detected in 45.5% of patients and were more frequently present among those with cTnT concentrations > or =0.1 ng/ml (13 of 18 vs 7 of 26 patients, p = 0.003). In these patients, mean plasma concentrations of FM were significantly higher than in patients with cTnT <0.1 ng/ml (7.93 +/- 2.3 vs 3.12 +/- 0.6 microg/ml, p = 0.02). There was a close relationship between plasma levels of cTnT and FM (r = 0.74, p <0.004), prothrombin fragments F1+2 (r = 0.71, p = 0.046) and a trend to significance was noted for TAT (r = 0.42, p = 0.055). No significant correlation was observed with markers of the fibrinolytic system (plasminogen and alpha2-anti-plasmin). Plasma levels of cTnT > or =0.1 ng/ml identified a concomitant increase of hemostatic markers with a sensitivity, specificity and positive predictive value of 65, 79, and 72% for FM, 63, 76, and 67% for prothrombin fragments F1+2, and 58, 66, and 39% for TAT, respectively. CONCLUSIONS: In patients with UAP, cTnT identifies patients with increased procoagulant activity and is closely related to plasma levels of molecular markers of hemostatic activation. Therefore, cTnT alone or in combination with one of these markers may be helpful to identify patients requiring more potent antithrombin or antiplatelet therapy.


Asunto(s)
Angina Inestable/sangre , Miocardio/química , Troponina T/farmacología , Anciano , Angina de Pecho/sangre , Angina de Pecho/epidemiología , Angina Inestable/epidemiología , Biomarcadores/sangre , Coagulación Sanguínea/efectos de los fármacos , Estudios de Cohortes , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/efectos de los fármacos , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Hemostasis/fisiología , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/epidemiología , Fragmentos de Péptidos/metabolismo , Plasminógeno/metabolismo , Protrombina/metabolismo , Troponina T/sangre , Troponina T/fisiología , alfa 2-Antiplasmina/metabolismo
16.
Am J Cardiol ; 85(7): 815-20, 2000 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-10758919

RESUMEN

Depressed heart rate variability (HRV) has been associated with adverse outcome during and after acute myocardial infarction (AMI). The effects of reperfusion in AMI on the course of HRV have not been well characterized as yet. We analyzed 123 consecutive patients with a first AMI who underwent successful reperfusion (Thrombolysis In Myocardial Infarction grades 2 and 3) by primary percutaneous transluminal coronary angioplasty (PTCA). Time- and frequency-domain HRV was measured from 24-hour Holter monitoring, which began at hospital admission. Mean RR interval increased significantly after successful PTCA. Reperfusion immediately caused an immediate transient depression of HRV, which was followed by a significant increase of HRV. Quantitative markers of sympathetic activity and sympathovagal balance, such as SD of the averages of NN intervals in all 5-minute segments, and low- and/or high-frequency ratio continuously decreased within the observation period. Patients with anterior AMI exhibited the same pattern of temporal changes of HRV, with, however, lower absolute values for HRV and mean RR interval than patients with non-anterior AMI. Subgroup analysis in 21 patients with reperfusion > 12 hours after onset of pain showed that the biphasic profile of HRV and the marked increase of mean RR interval was absent. Furthermore, in patients with late reperfusion, HRV was significantly lower compared with those with early reperfusion. Thus, timely reperfusion in AMI leads to a biphasic effect on autonomic tone, characterized by a transient suppression, followed by a significant activation of the vagal tone, as well as an attenuation of sympathetic activity. Recovery of HRV may contribute to the benefits of early reperfusion in AMI.


Asunto(s)
Angioplastia Coronaria con Balón , Ritmo Circadiano/fisiología , Frecuencia Cardíaca/fisiología , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/terapia , Adulto , Anciano , Electrocardiografía Ambulatoria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos
17.
Drugs ; 41 Suppl 1: 3-10, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1712269

RESUMEN

In clinical pharmacology studies, cilazapril, after its bioactivation to cilazaprilat, was characterised as a potent, reversible angiotensin converting enzyme (ACE) inhibitor with a terminal half-life of 30 to 50 hours, which is consistent with saturable binding to ACE. Despite the arterial vasodilatation, only slight increases in heart rate occurred during cilazapril administration. Cilazapril had no acute effect on cardiovascular reflexes, and increased effective renal plasma flow slightly. Glomerular filtration rate remained unaltered. A close positive correlation was found between the cilazaprilat plasma concentration and degree of ACE inhibition. The potency of cilazaprit, defined as the concentration of cilazaprilat causing 50% inhibition of ACE, was approximately 1 microgram/L plasma. In short term studies in patients with hypertension, it appeared that more than 90% inhibition of plasma ACE was needed to obtain blood pressure reduction. Results of various dose-response studies established the indirect relationship between dose, the plasma concentration of the drug, and the blood pressure response, and identified the dose producing the maximal effect to be 5mg. Cilazapril inhibited ACE for a relatively long period which was extended in patients with severe chronic renal impairment or hepatic failure. In these patients a reduction of the dose and/or less frequent administration is recommended. There was no clinically relevant interaction of cilazapril with food, furosemide (frusemide), digoxin or coumarins. The effects of hydrochlorothiazide on sodium and chloride excretion were potentiated by cilazapril, and an additive effect of propranolol and nitrendipine on the blood pressure response to cilazapril was observed. An interaction with indomethacin and cilazapril might occur, potentially reducing the blood pressure-lowering effect of cilazapril. In general, cilazapril was well tolerated.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Piridazinas/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacocinética , Cilazapril , Humanos , Piridazinas/farmacocinética
18.
Mol Cell Endocrinol ; 184(1-2): 51-63, 2001 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-11694341

RESUMEN

The effect of over-expressing neuronal calcium sensor 1 (NCS-1) upon stimulated adrenocorticotrophin (ACTH) secretion was studied in AtT-20 cells. Stably-transfected AtT-20 cell lines over-expressing NCS-1 were obtained and compared to wild type AtT-20 cells. Corticotrophin releasing factor (CRF-41)-stimulated ACTH secretion from NCS-1 over-expressing cells was significantly reduced from that obtained in wild type AtT-20 cells. The effects of other stimulants of ACTH secretion from wild type AtT-20 cells were not attenuated in NCS-1 over-expressing cells. Calcium, guanosine 5'-O-(3'-thiotriphosphate) (GTP-gamma-S) and mastoparan stimulated ACTH secretion from permeabilised wild type AtT-20 and NCS-1 over-expressing AtT-20 cells with significantly greater ACTH secretion obtained in NCS-1 over-expressing cells. This study shows that in intact cells over-expression of NCS-1 reduces exocytotic ACTH release, while in permeabilised cells increases ACTH release. NCS-1 has multiple cellular targets and that directly and indirectly via these targets acts to increase the releasable ACTH pool while inhibiting CRF-41 stimulus-secretion coupling.


Asunto(s)
Hormona Adrenocorticotrópica/efectos de los fármacos , Proteínas de Unión al Calcio/farmacología , Neuropéptidos/farmacología , Adenohipófisis/citología , Hormona Adrenocorticotrópica/metabolismo , Animales , Calcio/farmacología , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Hormona Liberadora de Corticotropina/farmacología , AMP Cíclico/metabolismo , Relación Dosis-Respuesta a Droga , Expresión Génica , Guanosina 5'-O-(3-Tiotrifosfato)/farmacología , Péptidos y Proteínas de Señalización Intercelular , Ratones , Microscopía Confocal , Proteínas Sensoras del Calcio Neuronal , Neuropéptidos/genética , Neuropéptidos/metabolismo , Péptidos , Transfección , Células Tumorales Cultivadas , Venenos de Avispas/farmacología
19.
Chest ; 113(5): 1415-7, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9596329

RESUMEN

A 26-year-old apparently healthy man with numerous pigmented skin lesions collapsed during an evening party and was resuscitated from ventricular fibrillation. Hypertrophic cardiomyopathy and subaortic tunnel were disclosed by angiocardiography. A diagnosis of cardiomyopathic lentiginosis/lentigines (multiple), electrocardiographic abnormalities, ocular hypertelorism, pulmonary stenosis, abnormalities of the genitalia, retardation of growth, and deafness (sensorineural) syndrome was made. The patient then underwent treatment with an implantable pacer-cardioverter-defibrillator device. Further evaluation revealed several well-established features of the disorder. This is the first reported case of survival from ventricular fibrillation associated with this rare and little known multifaceted syndrome. Disseminated lentiginosis must prompt clinicians to evaluate such cases further since underlying disorders may be associated with considerable morbidity and, apparently, sudden death.


Asunto(s)
Cardiomiopatía Hipertrófica/complicaciones , Paro Cardíaco/etiología , Lentigo/complicaciones , Fibrilación Ventricular/etiología , Anomalías Múltiples/diagnóstico , Adulto , Sordera/complicaciones , Desfibriladores Implantables , Electrocardiografía , Genitales Masculinos/anomalías , Trastornos del Crecimiento/complicaciones , Humanos , Hipertelorismo/complicaciones , Masculino , Estenosis de la Válvula Pulmonar/complicaciones , Síndrome , Fibrilación Ventricular/prevención & control
20.
Heart ; 79(6): 560-7, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10078082

RESUMEN

OBJECTIVE: To assess the effect of defibrillation shocks on cardiac and circulating catecholamines. DESIGN: Prospective examination of myocardial catecholamine balance during dc shock by simultaneous determination of arterial and coronary sinus plasma concentrations. Internal countershocks (10-34 J) were applied in 30 patients after initiation of ventricular fibrillation for a routine implantable cardioverter defibrillator test. Another 10 patients were externally cardioverted (50-360 J) for atrial fibrillation. MAIN OUTCOME MEASURES: Transcardiac noradrenaline, adrenaline, and lactate gradients immediately after the shock. RESULTS: After internal shock, arterial noradrenaline increased from a mean (SD) of 263 (128) pg/ml at baseline to 370 (148) pg/ml (p = 0.001), while coronary sinus noradrenaline fell from 448 (292) to 363 (216) pg/ml (p = 0.01), reflecting a shift from cardiac net release to net uptake. After external shock delivery, there was a similar increase in arterial noradrenaline, from 260 (112) to 459 (200) pg/ml (p = 0.03), while coronary sinus noradrenaline remained unchanged. Systemic adrenaline increased 11-fold after external shock (p = 0.01), outlasting the threefold rise following internal shock (p = 0.001). In both groups, a negative transmyocardial adrenaline gradient at baseline decreased further, indicating enhanced myocardial uptake. Cardiac lactate production occurred after ventricular fibrillation and internal shock, but not after external cardioversion, so the neurohumoral changes resulted from the defibrillation process and not from alterations in oxidative metabolism. CONCLUSIONS: A dc shock induces marked systemic sympathoadrenal and sympathoneuronal activation, but attenuates cardiac sympathetic activity. This might promote the transient myocardial depression observed after electrical discharge to the heart.


Asunto(s)
Fibrilación Atrial/terapia , Sistema Nervioso Autónomo/fisiopatología , Cardioversión Eléctrica , Fibrilación Ventricular/terapia , Adulto , Anciano , Fibrilación Atrial/sangre , Fibrilación Atrial/fisiopatología , Desfibriladores Implantables , Epinefrina/sangre , Femenino , Humanos , Ácido Láctico/sangre , Masculino , Persona de Mediana Edad , Miocardio/metabolismo , Norepinefrina/sangre , Estudios Prospectivos , Fibrilación Ventricular/sangre , Fibrilación Ventricular/fisiopatología
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