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1.
Cell Death Dis ; 15(5): 345, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769311

RESUMO

Treatment-naïve small cell lung cancer (SCLC) is typically susceptible to standard-of-care chemotherapy consisting of cisplatin and etoposide recently combined with PD-L1 inhibitors. Yet, in most cases, SCLC patients develop resistance to first-line therapy and alternative therapies are urgently required to overcome this resistance. In this study, we tested the efficacy of dinaciclib, an FDA-orphan drug and inhibitor of the cyclin-dependent kinase (CDK) 9, among other CDKs, in SCLC. Furthermore, we report on a newly developed, highly specific CDK9 inhibitor, VC-1, with tumour-killing activity in SCLC. CDK9 inhibition displayed high killing potential in a panel of mouse and human SCLC cell lines. Mechanistically, CDK9 inhibition led to a reduction in MCL-1 and cFLIP anti-apoptotic proteins and killed cells, almost exclusively, by intrinsic apoptosis. While CDK9 inhibition did not synergise with chemotherapy, it displayed high efficacy in chemotherapy-resistant cells. In vivo, CDK9 inhibition effectively reduced tumour growth and improved survival in both autochthonous and syngeneic SCLC models. Together, this study shows that CDK9 inhibition is a promising therapeutic agent against SCLC and could be applied to chemo-refractory or resistant SCLC.


Assuntos
Quinase 9 Dependente de Ciclina , Indolizinas , Neoplasias Pulmonares , Compostos de Piridínio , Carcinoma de Pequenas Células do Pulmão , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Quinase 9 Dependente de Ciclina/metabolismo , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/patologia , Humanos , Animais , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Linhagem Celular Tumoral , Camundongos , Compostos de Piridínio/farmacologia , Compostos de Piridínio/uso terapêutico , Indolizinas/farmacologia , Óxidos N-Cíclicos/farmacologia , Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
2.
Am J Cardiol ; 85(8): 1007-11, 2000 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10760344

RESUMO

Shortened head-up tilt testing (HUT) potentiated with sublingual nitroglycerin (60 degrees passive standing for 20 minutes followed, if negative, by 400 microg of sublingual nitroglycerin spray with the test continuing for another 20 minutes) differs from conventional nitroglycerin HUT for a shorter drug-free phase (20 vs 45 minutes). To compare the positivity rate of the 2 protocols, both tests were performed in a randomized sequence in 10 patients with unexplained syncope (study 1), and another 42 patients were randomly assigned either to conventional or to shortened nitroglycerin HUT (study 2). To evaluate the reproducibility of the shortened nitroglycerin HUT, another 38 patients with unexplained syncope underwent 2 consecutive tests within a 7+/-8 day interval (study 3). Finally, to evaluate the specificity of the test, 47 control subjects underwent shortened nitroglycerin HUT (study 4). Seven positive responses were observed during shortened nitroglycerin HUT, and there were 8 positive responses during conventional nitroglycerin HUT (p = NS) in the study 1 group. Fifteen positive (71%) responses, 5 negative responses, and 1 exaggerated response were observed during shortened nitroglycerin HUT; 16 positive (76%, p = NS vs. shortened nitroglycerin HUT), 3 negative, and 2 exaggerated responses were observed during conventional nitroglycerin HUT in the study 2 group. During the first test, 21 patients (55%) had a positive, 15 patients had a negative, and 2 patients had an exaggerated response in study group 3. During the second test, 15 positive (39%), 19 negative, and 4 exaggerated responses were observed. Thus, the reproducibility was 67% for a positive and 94% for a negative test. In control subjects, 2 positive (4%) responses, 38 negative, and 7 exaggerated responses were observed with a specificity of 96% in study group 4. In patients with unexplained syncope, shortened nitroglycerin HUT allowed a positivity rate similar to that of the conventional test. Moreover, the shortened test provided a high specificity and adequate reproducibility for both the positive and the negative responses.


Assuntos
Nitroglicerina , Síncope/diagnóstico , Teste da Mesa Inclinada/métodos , Vasodilatadores , Administração Sublingual , Adulto , Feminino , Humanos , Masculino , Nitroglicerina/administração & dosagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Síncope/etiologia , Vasodilatadores/administração & dosagem
3.
J Am Geriatr Soc ; 48(2): 146-53, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10682943

RESUMO

OBJECTIVES: Exercise tolerance is reduced with advancing age. Identification of potentially reversible determinants of the age-related decrement in exercise tolerance, which remain largely unexplored in older subjects and in patients recovering from a recent myocardial infarction (MI), may have useful therapeutic implications. The objective of this study was to identify the independent determinants of exercise tolerance in older patients with a recent MI. DESIGN, SETTING, AND PARTICIPANTS: Data is from baseline assessment of 265 post-MI patients (age range 45-85 years) enrolled in the Cardiac Rehabilitation in Advanced Age randomized, controlled trial. Patients with major comorbidities or severe MI complications were excluded from the trial. Exercise tolerance was determined from symptom-limited exercise testing and expressed as total work capacity (TWC, kg.m) or peak oxygen consumption (VO2peak, mL/kg/min). The associations between both TWC and VO2peak and baseline demographic, social, clinical, and neuropsychological variables and an index of health-related quality of life were determined with univariate and multivariate analysis. RESULTS: With univariate analysis, TWC decreased by 1285 kg.m per decade of increasing age between 45 and 85 years of age. With multivariate analysis, TWC decreased by 922 kg.m per decade. Increasing age (P < .001), female gender (P < .001), a small body surface area (P < .001), a low level of usual physical exercise before MI (P < .002), and the presence of post-MI depressive symptoms (P < .024) were independently associated with a lower TWC. The same factors, in addition to a small arm muscle area (P < .002), were also independently associated with a lower VO2peak. CONCLUSIONS: Age per se accounts for approximately 70% of the age-related decay in TWC or VO2peak. However, the inclusion of modifiable factors such as physical exercise and depression in the prediction model reinforces the importance of a multidimensional approach to the evaluation and treatment of older patients with a recent MI.


Assuntos
Tolerância ao Exercício/fisiologia , Infarto do Miocárdio/fisiopatologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Análise de Variância , Ansiedade/psicologia , Composição Corporal , Superfície Corporal , Depressão/psicologia , Teste de Esforço , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Análise Multivariada , Músculo Esquelético/anatomia & histologia , Infarto do Miocárdio/psicologia , Consumo de Oxigênio/fisiologia , Qualidade de Vida , Fatores Sexuais
5.
J Chemother ; 16(3): 293-7, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15330328

RESUMO

Neuroendocrine tumors, particularly those of gastrointestinal tract origin, have a predisposition for metastasizing to the liver, causing parenchymal substitution and paraneoplastic syndrome. Lipiodol embolization combined with anticancer drugs is a recent tool in regional therapy. It has been proven that chemoembolization reduces tumor bulk and hormone levels, and that it palliates the symptoms of many patients with liver-dominant neuroendocrine metastases. Beginning in December 1988, ten patients with unresectable and chemotherapy-refractory liver metastatic neuroendocrine tumors were treated with chemoembolization based on a mixture of lipiodol, mitomycin, cisplatin, epirubicin, followed by gelfoam powder and contrast media. Toxicity encountered included: upper right quadrant pain requiring narcotics, elevation of lactate dehydrogenase, alkaline phosphatase, and transaminases. One patient had liver abscess and persistent fever for 2 weeks. We obtained two complete remissions lasting 12 and 34 months and 5 partial remissions. The median survival was 22 months. Four patients had urinary elevation of 5-hydroxyindolacetic acid (5-HIAA). They showed more than a 75% decrease in urinary secretion after treatment. In a patient with transplanted liver we noticed a partial response lasting 7 months. We conclude that chemoembolization will improve the clinical condition of a significant percentage of patients with liver metastases, that future therapy of carcinoid tumors will be based on specific tumor biology and that treatment will be customized for each individual patient combining the use of cytoreductive procedures including radiofrequency ablation, laser treatment and chemoembolization.


Assuntos
Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Tumores Neuroendócrinos/secundário , Tumores Neuroendócrinos/terapia , Cuidados Paliativos/métodos , Adulto , Feminino , Seguimentos , Artéria Hepática , Humanos , Infusões Intra-Arteriais , Fígado/efeitos dos fármacos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tumores Neuroendócrinos/mortalidade , Estudos Prospectivos , Medição de Risco , Análise de Sobrevida , Resultado do Tratamento
6.
Angiology ; 43(12): 980-7, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1466486

RESUMO

The accuracy and reproducibility of a new automatic device (P) specially designed for noninvasive blood pressure monitoring during the exercise stress test were evaluated in 50 consecutive subjects (34 normotensives and 16 hypertensives). Automatic measurements were compared with those taken by a sphygmomanometer (RR). A good agreement between systolic pressure values obtained by the two methods was found (RR 159 +/- 30 mmHg, P 158 +/- 28 mmHg, mean difference = -1.53 +/- 13 mmHg, p = 0.166, ns). On the contrary the new device significantly underestimated diastolic pressure values (RR 89.3 +/- 13 mmHg; P 84 +/- 13 mmHg, mean difference -5.37 +/- 9.3, p < 0.001). In conclusion the new device seems able to measure systolic but underestimates diastolic blood pressure both in hypertensives and in normotensives during the effort test.


Assuntos
Determinação da Pressão Arterial/instrumentação , Teste de Esforço , Adulto , Idoso , Diástole , Estudos de Avaliação como Assunto , Feminino , Humanos , Hipertensão/diagnóstico , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sístole
7.
Angiology ; 41(8): 616-20, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2117862

RESUMO

In this study the concentration of plasma breakdown products of cross-linked fibrin (XDP), serum fibrinogen-fibrin degradation products (FDP), and plasma fibrinogen were measured before and at the end of the administration of single-chain recombinant tissue-type plasminogen activator (rt-PA, 100 mg IV over three hours) or streptokinase (1.5 million units over one hour), respectively, in two groups, each composed of 22 patients with acute myocardial infarction. The XDP concentration was not statistically different between the two groups at the end of thrombolytic treatment, whereas FDP and fibrinogen concentrations were significantly different (FDP: streptokinase 396 +/- 287 vs rt-PA 177 +/- 222 micrograms/mL, p less than 0.01; fibrinogen: streptokinase 71 +/- 43 vs rt-PA 181 +/- 49 mg/dL, p less than 0.001). These results indicate that the two drugs have equipotent thrombolytic activity at this administration regimen but that rt-PA causes a markedly more selective lysis of fibrin in comparison with streptokinase.


Assuntos
Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrina/metabolismo , Fibrinogênio/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Estreptoquinase/uso terapêutico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Feminino , Fibrinólise , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Proteínas Recombinantes/uso terapêutico
8.
Phys Rev Lett ; 68(25): 3718-3720, 1992 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-10045779
10.
Phys Rev B Condens Matter ; 46(9): 5727-5730, 1992 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10004364
11.
J Cardiovasc Pharmacol ; 14 Suppl 9: S72-4, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2483237

RESUMO

Oral anticoagulants have been used for over three decades in long-term post-myocardial infarction treatment. The cumulated results of the early clinical trials showed a reduction of general mortality of 20%. The reduction reached 60% when trials with adequate anti-coagulant treatment were considered. The most recent study (Sixty Plus Study 1980), a very well designed and conducted study with optimal anticoagulant dosage, reported a 2-year reduction in total mortality of 43% (p less than 0.017 vs. controls) and a reduction of reinfarction of 64.1% (p less than 0.0002). However, the incidence of major hemorrhagic episodes (27 vs. 3) and of definite intracranial hemorrhages (8 vs. 1) was very high in the treatment group with 6 deaths vs. 1 due to hemorrhage. An alternative way for controlling blood clotting activation and thrombin generation appears to be low-dose heparin treatment. In a randomized controlled clinical trial heparin administered in low doses (12,500 i.u. daily by subcutaneous route) reduced the reinfarction rate by 63% (p less than 0.05 vs. controls) and general mortality by 47% (p less than 0.05) over 2 years. Even the frequency of the fatalities attributable to thromboembolic events was significantly decreased. No hemorrhagic complication occurred in any patients. Oral anticoagulants and low-dose heparin appears to be equally effective in secondary prevention of myocardial infarction. However, low-dose heparin treatment appears to be free from the elevated risk of major hemorrhages related to oral anticoagulants and does not require any blood clotting check.


Assuntos
Anticoagulantes/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Doença Crônica , Humanos , Infarto do Miocárdio/prevenção & controle , Recidiva
12.
G Ital Cardiol ; 23(1): 69-72, 1993 Jan.
Artigo em Italiano | MEDLINE | ID: mdl-8491345

RESUMO

We report the case of an 82-year-old woman who developed bradyarrhythmia with A-V dissociation and shock, followed by an acute pancreatitis, after ingestion of 2400 mg of verapamil per os for suicidal purposes. Despite her advanced age, the patient promptly improved by a conventional therapy even though started several hours after ingestion of the drug.


Assuntos
Tentativa de Suicídio , Verapamil/intoxicação , Idoso , Idoso de 80 Anos ou mais , Overdose de Drogas/terapia , Feminino , Humanos
13.
Am Heart J ; 122(6): 1609-16, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1957756

RESUMO

To evaluate the accuracy of exercise two-dimensional echocardiography for the recognition of coronary artery disease, 53 patients (46 men and 7 women, age range 35 to 69 years) without either previous myocardial infarction or resting wall motion abnormalities, were studied. According to coronary angiography 26 had normal coronary arteries, 14 had one-vessel, seven had two-vessel, and six had three-vessel disease. After withdrawal of any therapy, all patients underwent a single exercise stress test with a stress table during which cine-loop digitized echocardiography was acquired and 74 MBq of thallium-201 (TI-201) were injected. Echocardiographic images were evaluated at rest and at peak exercise. Three-view planar scintigraphic images were collected immediately after exercise and 4 hours later. For the overall recognition of coronary artery disease, exercise electrocardiography had 77.8% sensitivity and 65.4% specificity; myocardial scintigraphy had 100% sensitivity and 92.3% specificity; and exercise echocardiography had 92.6% sensitivity and 96.2% specificity (both NS versus myocardial scintigraphy). Global accuracy was 71.7% for exercise electrocardiography, 94.3% for stress echocardiography, and 96.2% for myocardial scintigraphy. For the classification of the individual involved coronary arteries, the sensitivity of myocardial scintigraphy was 84.8% and that of exercise echocardiography was 63% (p less than 0.01); the related specificities were 98% and 98.2% respectively (NS). It may be concluded that exercise echocardiography is highly accurate for the recognition of coronary artery disease, whereas it appears less sensitive in the identification of the involved vessels, particularly in patients with multivessel disease.


Assuntos
Doença das Coronárias/diagnóstico , Ecocardiografia/métodos , Coração/diagnóstico por imagem , Radioisótopos de Tálio , Adulto , Idoso , Cateterismo Cardíaco , Angiografia Coronária , Estudos de Avaliação como Assunto , Teste de Esforço/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Sensibilidade e Especificidade
14.
Circulation ; 83(5 Suppl): III50-3, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2022048

RESUMO

The aim of the present study was to investigate the ventilatory anaerobic threshold in patients with exercise-induced myocardial ischemia. Ventilatory volumes and gas exchanges were measured during treadmill stress testing in 36 patients (11 with previous myocardial infarction) with electrocardiographic criteria of myocardial ischemia during the test and in 23 healthy, untrained control subjects of equivalent age. The anaerobic threshold was detected in 32 of 36 patients (89%) and in 22 of 23 control subjects (96%). The anaerobic threshold was significantly lower in patients than in control subjects (13.5 +/- 1.9 versus 19.7 +/- 1.7 ml/kg per minute VO2, p less than 0.001). In the 21 patients without previous myocardial infarction, the anaerobic threshold was also significantly lower than in the control subjects (13.9 +/- 1.6 versus 19.7 +/- 1.7 ml/kg per minute VO2, p less than 0.001). Among the 21 patients without previous myocardial infarction, the 12 with a low ischemic threshold, which occurred during the first three steps of the modified Bruce protocol, had an anaerobic threshold significantly lower than the other nine patients (13.1 +/- 1.5 versus 14.9 +/- 1.0 ml/kg per minute VO2, p less than 0.01). However, even in the patients with a moderate to high ischemic threshold, the anaerobic threshold was significantly lower than in the control subjects (p less than 0.001). These data show that the anaerobic threshold can be measured in the great majority of patients with exercise-induced myocardial ischemia. The low anaerobic threshold level indicates a relevant functional impairment in these patients.


Assuntos
Limiar Anaeróbio , Doença das Coronárias/etiologia , Exercício Físico , Adulto , Idoso , Doença das Coronárias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Valores de Referência
15.
Am Heart J ; 115(1 Pt 1): 60-7, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3276111

RESUMO

Increased thrombin generation is frequently associated with an increase in anginal activity. A cross-over, single-blind, completely randomized study was planned in order to evaluate whether the control of thrombin generation affected the increase in anginal activity. After discharge from the hospital, 24 patients (18 men and 6 women, aged 40 to 69 years) suffering from spontaneous angina were followed up to 12 months and were alternatively treated during two consecutive 6-month periods with calcium heparin, 12,500 IU by the subcutaneous route, or with placebo by the intramuscular route, in addition to the usual antianginal medications. Thrombin generation and clinical activity of angina were assessed every 15 days by measuring fibrinopeptide A (FPA) plasma levels and by grading in three classes (symptomless, mildly symptomatic, and severely symptomatic) the anginal activity on the basis of the number and the time concentration of the ischemic attacks and ECG changes. Low-dose heparin treatment significantly reduced both the FPA plasma level (from 4.1 +/- 3.7 to 2.3 +/- 1.8 ng/ml, p less than 0.001) and the clinical activity of angina. During heparin treatment, the frequency of the observations in the severely and mildly symptomatic classes decreased, respectively, by 53% and by 30%, whereas that in the symptomless class increased by 23% (p less than 0.001) in comparison with the period on placebo. Present results indicate that the control of thrombin generation obtained by low-dose heparin treatment favorably affects the degree of anginal activity in patients with spontaneous angina.


Assuntos
Angina Pectoris/fisiopatologia , Fibrinogênio/sangue , Fibrinopeptídeo A/sangue , Heparina/administração & dosagem , Trombose/tratamento farmacológico , Idoso , Angina Pectoris/sangue , Angina Pectoris/tratamento farmacológico , Ensaios Clínicos como Assunto , Esquema de Medicação , Feminino , Humanos , Masculino , Cooperação do Paciente , Distribuição Aleatória
16.
G Ital Cardiol ; 22(3): 257-65, 1992 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-1426770

RESUMO

Propafenone efficacy in conversion of atrial fibrillation to sinus rhythm has been well documented. In this study we considered propafenone efficacy according to a graduated protocol of administration. Forty-two patients with recent-onset atrial fibrillation, without left ventricular failure, ischemic symptoms and in absence of antiarrhythmical treatment, were treated according to the following protocol: propafenone 1 mg/kg i.v. (5 min) followed, in the non-responder patient group, by a second dose, 0.5 mg/kg i.v. (15 min). Patients with persistent atrial fibrillation received 900 mg/daily of propafenone per os, at home for two days. Thereafter, patients still not restored to sinus rhythm were considered non-responders. Patients who were converted to sinus rhythm received 450 mg daily of the drug (oral administration), at home, as antiarrhythmical prophylaxis, for three months. Thirty-nine patients were converted to sinus rhythm (92.8%), 24 of them after intravenous propafenone (57.2%), and the other 15 (35.6%) after oral administration of the drug. The average heart rate in patients not converted to sinus rhythm with intravenous propafenone was significantly reduced after drug administration, compared to basal values (from 136.4 +/- 18.1 to 107.1 +/- 17.6, p < 0.01), allowing home treatment. No major cardiac effects were observed after infusion, nor after oral administration of propafenone. During a three-month follow-up we observed 3 cases of relapsed atrial fibrillation and 2 discontinued treatments due to minor gastroenteric side effects. In conclusion, propafenone therapy in ambulatory regimen is safe and effective in patients with recent-onset atrial fibrillation. In many patients refractory to IV treatment, further therapeutic success may be achieved following oral propafenone administration.


Assuntos
Assistência Ambulatorial , Fibrilação Atrial/tratamento farmacológico , Propafenona/uso terapêutico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/fisiopatologia , Protocolos Clínicos , Eletrocardiografia , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Propafenona/administração & dosagem , Fatores de Tempo
17.
Am Heart J ; 120(1): 12-21, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2360496

RESUMO

In order to investigate whether coronary vasodilating prostaglandins (PGI2 and PGE2) have a role in the pathophysiology of myocardial ischemia, 26 patients with angina pectoris and 23 control subjects (nonischemic patients) were studied by assessing coronary hemodynamics and prostaglandin formation in relation to sympathetic stimulation. Following a cold pressor test (CPT), coronary prostaglandin output markedly increased (p less than 0.001) and coronary vascular resistance (CVR) decreased (p less than 0.001) in all control subjects. In contrast, in anginal patients prostaglandins in the coronary sinus were undetectable and after CPT prostaglandin output did not increase, whereas CVR paradoxically increased (p less than 0.001). In control subjects the inhibition of coronary prostaglandin formation (by ketoprofen [1 mg/kg intravenously] or by aspirin [15 mg/kg intravenously]) caused a paradoxical increase of CVR following CPT (p less than 0.001). In anginal patients the inhibition of prostaglandins further exaggerated the increase of CVR after CPT (p less than 0.001). These results indicate that coronary vasodilating prostaglandin PGI2 and PGE2 play a role in modulating coronary vascular response to sympathetic stimulation induced by CPT. Their defective production in anginal patients may be responsible for the paradoxical increase in CVR following sympathetic stimulation.


Assuntos
Angina Pectoris/metabolismo , Vasos Coronários/metabolismo , Prostaglandinas E/metabolismo , Prostaglandinas F/metabolismo , Resistência Vascular/fisiologia , Adulto , Angina Pectoris/fisiopatologia , Aspirina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Temperatura Baixa , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/fisiopatologia , Feminino , Humanos , Cetoprofeno/farmacologia , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Consumo de Oxigênio/fisiologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos
18.
G Ital Cardiol ; 21(6): 609-17, 1991 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-1743443

RESUMO

To investigate whether magnetic resonance imaging (NMR) can detect alterations in LV contractility during myocardial ischemia, ten patients aged 32-72 with coronary artery disease underwent ECG gated NMR performed at 0.5 Tesla after intravenous infusion of high dose dipyridamole (DP) (0.7 mg/Kg) over 5 minutes. LV contraction in planes similar to echo short axis projection was imaged under condition, 3' and 15-20' after infusion of DP by fast multiphasic imaging (FMI), multiple angulated cine-NMR sequence with a temporal resolution of 50 m/sec. Entity and size of perfusion defects after DP were determined by Tc 99m MIBI myocardial scintigraphy. In all patients changes in LV contractility appeared at NMR in the same site of perfusion impairments revealed with MIBI. In 8 patients the alterations lasted even more than 20' after the first NMR scan. NMR provides the opportunity of performing long-lasting assessment of ventricular wall contractility and enables to exactly localize the site and extension of kinetic changes as well as their time of onset and time duration.


Assuntos
Meios de Contraste/administração & dosagem , Doença das Coronárias/diagnóstico , Dipiridamol , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Miocárdio/patologia , Nitrilas , Compostos de Organotecnécio , Doença das Coronárias/induzido quimicamente , Eletrocardiografia , Estudos de Avaliação como Assunto , Coração/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Filmes Cinematográficos , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único/métodos
19.
Am Heart J ; 119(4): 848-54, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2108576

RESUMO

To investigate a physiologic role of coronary prostacyclin (PGI2) and prostaglandin E2 (PGE2) 30 patients who were not affected by coronary heart disease were evaluated for coronary hemodynamics and coronary PGI2 and PGE2 production. Inhibition of coronary prostaglandin biosynthesis by ketoprofen (1 mg/kg) or aspirin (15 mg/kg) administered intravenously did not significantly change coronary hemodynamics in resting conditions. In all patients cold pressor tests induced significant increases in coronary blood flow (p less than 0.001) and decreases in coronary vascular resistance (p less than 0.001) without changes in cardiac oxygen extraction and with consequent increases in calculated myocardial oxygen consumption. Simultaneously, a marked increase in coronary PGI2 (as 6-keto-PGF1 alpha) and PGE2 formation was observed (p less than 0.001). Both ketoprofen (1 mg/kg) and aspirin (15 mg/kg) administration completely abolished PGI2 and PGE2 formation that was induced by cold pressor test and caused a paradoxical increase in coronary vascular resistance (ketoprofen: p less than 0.02; aspirin: p less than 0.05). The results of this study support a physiologic role for the coronary prostaglandins in modulating coronary vascular response to sympathetic stimulation in nonischemic patients.


Assuntos
Circulação Coronária/fisiologia , Vasos Coronários/fisiologia , Dinoprostona/fisiologia , Epoprostenol/fisiologia , Sistema Nervoso Simpático/fisiologia , Resistência Vascular/fisiologia , Adulto , Aspirina , Temperatura Baixa , Dinoprostona/antagonistas & inibidores , Epoprostenol/antagonistas & inibidores , Feminino , Humanos , Cetoprofeno , Masculino , Vasodilatação/fisiologia
20.
Haemostasis ; 20 Suppl 1: 129-31, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2083864

RESUMO

Heparin, after subcutaneous administration, has been found to be able to bind to endothelial receptors both in rabbits and in humans. N-sulphonate 35S-heparin remains bound in rabbits for at least 24 h and is able to enhance the inactivation process of thrombin and factor Xa. Heparin subcutaneously (200 U/kg) injected for 2 weeks resulted in an enhanced inactivation of thrombin and factor Xa by the endothelium. The antithrombin-enhancing activity persists longer than the anti-Xa activity. In man, daily subcutaneous administration of heparin (12,500 U/day) for 2 weeks significantly reduces the increased fibrinopeptide A plasma levels and normalizes the increased 125I-fibrinogen turnover. The present work indicates that heparin administration at a low dose represents a treatment able to remarkably enhance the antithrombotic properties of the vessel wall, independently of the presence of detectable heparin levels in the circulating blood.


Assuntos
Heparina/administração & dosagem , Animais , Endotélio Vascular/metabolismo , Inibidores do Fator Xa , Heparina/metabolismo , Humanos , Coelhos
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