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1.
Mol Ecol ; 21(1): 45-56, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22117930

RESUMO

The Neolithic transition has been widely debated particularly regarding the extent to which this revolution implied a demographic expansion from the Near East. We attempted to shed some light on this process in northeastern Iberia by combining ancient DNA (aDNA) data from Early Neolithic settlers and published DNA data from Middle Neolithic and modern samples from the same region. We successfully extracted and amplified mitochondrial DNA from 13 human specimens, found at three archaeological sites dated back to the Cardial culture in the Early Neolithic (Can Sadurní and Chaves) and to the Late Early Neolithic (Sant Pau del Camp). We found that haplogroups with a low frequency in modern populations-N* and X1-are found at higher frequencies in our Early Neolithic population (∼31%). Genetic differentiation between Early and Middle Neolithic populations was significant (F(ST) ∼0.13, P<10(-5)), suggesting that genetic drift played an important role at this time. To improve our understanding of the Neolithic demographic processes, we used a Bayesian coalescence-based simulation approach to identify the most likely of three demographic scenarios that might explain the genetic data. The three scenarios were chosen to reflect archaeological knowledge and previous genetic studies using similar inferential approaches. We found that models that ignore population structure, as previously used in aDNA studies, are unlikely to explain the data. Our results are compatible with a pioneer colonization of northeastern Iberia at the Early Neolithic characterized by the arrival of small genetically distinctive groups, showing cultural and genetic connections with the Near East.


Assuntos
DNA Mitocondrial/história , Haplótipos/genética , Agricultura/história , Arqueologia , DNA Mitocondrial/genética , Deriva Genética , História Antiga , Humanos , Oriente Médio , Filogeografia/história , Espanha
2.
Rev Port Cardiol ; 19(7-8): 823-8, 2000.
Artigo em Português | MEDLINE | ID: mdl-11014085

RESUMO

There is some controversy regarding the indications for transesophageal echocardiography in patients with suspected systemic embolism. The present case report refers to a 65 year old male admitted to the hospital for ischemic acute cerebrovascular accident, which was confirmed by cerebral computerized tomography. A transthoracic echocardiogram was performed showing right atrial and ventricular dilatation. A transesophageal echocardiogram was also performed to exclude thromboembolism and clarify dilatation of the right cavities. Mild spontaneous echocontrast was present in the left atrium without images of thrombus; an interatrial septal aneurysm with patent foramen ovale was found with right to left flow; an image compatible with a very mobile, large, proximal thrombus in the main pulmonary artery was observed. A venous duplex scan was performed, demonstrating venous thrombosis in the right popliteal and femoral veins. Pulmonary arteriography showed a large thrombus in the right pulmonary branch extending to the median lobe and a smaller thrombus in the left pulmonary branch. Apparently, the patient had no predisposing factors for thromboembolism. Full-dose heparin was started followed by oral anticoagulation. An inferior vena cava filter was implanted. At hospital discharge the pulmonary thrombus had disappeared and the right cardiac cavities had returned to normal size. The interatrial aneurysm had disappeared and foramen ovale was no longer patent. After 36 months of clinical follow up on oral anticoagulation, the patient remains asymptomatic without neurological sequelae nor respiratory distress.


Assuntos
Ecocardiografia Transesofagiana , Embolia Pulmonar/diagnóstico por imagem , Idoso , Humanos , Masculino , Embolia Pulmonar/tratamento farmacológico
5.
Rev Port Cardiol ; 18(9): 821-7, 1999 Sep.
Artigo em Português | MEDLINE | ID: mdl-10536472

RESUMO

The authors describe the main etiopathogenic factors and clinical importance of atrial fibrillation and analyse the results of catheter ablation of atrioventricular accessory pathways in Wolff-Parkinson-White syndrome. Atrial vulnerability is the principal mechanism and radiofrequency catheter ablation of atrioventricular accessory pathways seems to be useless to prevent atrial fibrillation.


Assuntos
Fibrilação Atrial/complicações , Síndrome de Wolff-Parkinson-White/complicações , Fibrilação Atrial/cirurgia , Ablação por Cateter , Humanos
6.
Rev Port Cardiol ; 18(6): 587-93, 1999 Jun.
Artigo em Português | MEDLINE | ID: mdl-10422454

RESUMO

UNLABELLED: Maximal oxygen consumption (VO2max) has an important prognostic value in patients with congestive heart failure (CHF). However, it requires a maximal exercise test, not often available for these patients. To overcome this limitation, we examined whether a simple time integral of oxygen pulse (OP) to submaximal exercise levels correlates with VO2max. METHODS: We performed a maximal symptom-limited treadmill exercise test, while measuring breath-by-breath oxygen consumption, using the CAEP protocol, in 24 patients with CHF (51 +/- 11 years, 18 males, sinus rhythm). No exercise was terminated due to ischemia or arrhythmias. All patients attained anaerobic threshold. Besides standard parameters, OP (ml) and time integral of OP (OPTI) were calculated at 2 minutes (OP-2 min and OPTI-2 min) and at 4 minutes (OP-4 min and OPTI-4 min) of exercise. Patients were divided in two groups according to VO2max: group I--VO2max > or = 16 ml/kg/min (14 patients) and group II--VO2max < 16 (10 patients). RESULTS: Age, sex, body surface and CHF etiology were similar in both groups. Exercise duration, maximal OP, time to anaerobic there shold, VO2 and OP at anaerobic there shold were higher in group I (p < 0.05). Comparing group I vs group II--OP-2 min: 6.2 +/- 1.5 vs 5.0 +/- 1.2 ml (p = 0.026); OP-4 min: 7.6 +/- 1.9 vs 5.4 +/- 1.2 (p = 0.001); OPTI-2 min: 3.1 +/- 1.1 vs 2.2 +/- 0.9 (p = 0.021) and OPTI-4 min: 15.2 +/- 4.4 vs 9.3 +/- 3.1 (p = 0.0007). The best correlation with VO2max was obtained for OPTI-4 min (r = 0.696). An OPTI-4 min value > or = 10 occurred in 13 patients of group I and in two patients of group II (p = 0.00013), with a predictive value of 87% for VO2max > 16 (sensitivity = 93%, specificity = 80%)--kappa index = 0.739. CONCLUSIONS: OPTI-4 min can be a useful tool for assessing cardiocirculatory functional status in patients with CHF and unable to perform a maximal exercise test.


Assuntos
Tolerância ao Exercício/fisiologia , Insuficiência Cardíaca/fisiopatologia , Consumo de Oxigênio/fisiologia , Adulto , Idoso , Feminino , Testes de Função Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
8.
Rev Port Cardiol ; 18(2): 141-7, 1999 Feb.
Artigo em Português | MEDLINE | ID: mdl-10221043

RESUMO

UNLABELLED: In patients with advanced heart failure (HF) submitted to tailored therapy, monitoring of systemic vascular resistance (SVR) is essential to establish an adequate hemodynamic response, being one of the end-points to achieve SVR < 18 Wood U (WU). PURPOSE: To correlate SVR value with parameters derived from the analysis of echo-Doppler aortic flow in patients with HF on tailored therapy, in order to allow a non-invasive semiquantitative evaluation of this hemodynamic end-point. METHODS: In 13 patients with dilated cardiomyopathy (eight idiopathic, five ischemic) and advanced HF (mean age 60 +/- 10 years, 10 male, all in sinus rhythm, NYHA class IV), admitted in the ICU and submitted to tailored therapy, serial simultaneous hemodynamic and echocardiographic studies were performed (2 to 5 per patient, overall 43 evaluations). The following parameters derived from the analysis of continuous wave aortic Doppler flow were analysed: peak velocity, acceleration, deacceleration and ejection times, systolic time intervals ratio, mean acceleration, mean deacceleration, acceleration, deacceleration and overall systolic flow velocity time integrals. RESULTS: SVR ranged from 10.4 to 41.9 WU (mean = 21.7, SD = 6.9). A significant correlation was found only with mean deacceleration (MnDc)-r = -0.60. MnDc ranged from 362 to 1162 cm/s2 (mean = 667, SD = 188) and proved to be independent from heart rate, systolic, diastolic and mean blood pressure, capillary wedge pressure, cardiac output, cardiac index and ejection volume. MnDc < 700 cm.s2 occurred in 25/28 evaluations with SVR > 18 WU and only in 3/15 evaluations with SVR < 18 WU-p = 0.00003. A MnDc value < 700 cm.s2 showed sensitivity = 89%, specificity = 80%, and predictive value = 89% for SVR > 18 WU (Kappa index = 0.693). CONCLUSION: Mean deacceleration of aortic continuous wave flow is reliable for semiquantitative evaluation of systemic vascular resistance and can be particularly useful for patients with advanced heart failure submitted to tailored therapy.


Assuntos
Aorta/diagnóstico por imagem , Aorta/fisiopatologia , Ecocardiografia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Resistência Vascular , Adulto , Idoso , Análise de Variância , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/fisiopatologia , Cateterismo de Swan-Ganz , Ecocardiografia/métodos , Ecocardiografia/estatística & dados numéricos , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Reologia/métodos , Reologia/estatística & dados numéricos , Sensibilidade e Especificidade
9.
Rev Port Cardiol ; 18(2): 149-53, 1999 Feb.
Artigo em Português | MEDLINE | ID: mdl-10221044

RESUMO

Transthoracic echocardiography has important limitations in the diagnosis of sinus venosus atrial septal defects in adults because of the posterior location of the defect. We review the role of transesophageal echocardiography in the diagnosis of this congenital heart disease in nine patients, as well as in the identification of associated abnormal pulmonary venous connections.


Assuntos
Ecocardiografia Transesofagiana , Comunicação Interatrial/diagnóstico por imagem , Adulto , Ecocardiografia , Ecocardiografia Transesofagiana/instrumentação , Ecocardiografia Transesofagiana/métodos , Feminino , Átrios do Coração/diagnóstico por imagem , Septos Cardíacos/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/anormalidades , Veias Pulmonares/diagnóstico por imagem
10.
Rev Port Cardiol ; 18(2): 177-8, 1999 Feb.
Artigo em Português | MEDLINE | ID: mdl-10221048

RESUMO

A 58-year-old male underwent a transesophageal echocardiogram for suspected aortic valve infective endocarditis, four years after surgery. The examination, performed with a multiplane probe, showed a pulsatile (systolic expansion) echo-free cavity in the intervalvular mitral-aortic region, communicating with the left ventricle outflow tract, with no signs of rupture to the left atrium or the aorta. These findings meet the criteria for the diagnosis of pseudoaneurysm of the mitral-aortic intervalvular fibrosa.


Assuntos
Falso Aneurisma/diagnóstico por imagem , Valva Aórtica/patologia , Aneurisma Cardíaco/diagnóstico por imagem , Implante de Prótese de Valva Cardíaca , Valva Mitral/patologia , Valva Aórtica/diagnóstico por imagem , Ecocardiografia Transesofagiana , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem
11.
Rev Port Cardiol ; 17(11): 889-92, 1998 Nov.
Artigo em Português | MEDLINE | ID: mdl-9927858

RESUMO

OBJECTIVE: To evaluate whether the changes in the ventilatory equivalent for carbon dioxide (VE/VCO2), during the early stages of cardiopulmonary exercise testing, can predict maximal oxygen consumption (VO2max) in patients with chronic heart failure. METHODS: We studied 38 patients (30 males, mean age 56 +/- 11 years) with chronic heart failure. All patients performed maximal symptom limited, treadmill exercise test with breath-by-breath respiratory gas analysis. They were divided in two groups according to their maximal oxygen consumption (group I-VO2max above 14 ml/kg/min and group II-VO2max below 14 ml/kg/min). In both groups, we analysed VE/VCO2 at rest, at the anaerobic threshold (AT) and at peak exercise, and the percentage of VE/VCO2 reduction from rest to AT. RESULTS: Eleven patients had a VO2max below 14 ml/kg/min (group II). At rest VE/VCO2 = 53 +/- 13 in group II versus 47 +/- 10 in group I (p = 0.048), at the AT VE/VCO2 = 46 +/- 12 in group II versus 36 +/- 7 in group I (p = 0.001) and at peak exercise VE/VCO2 = 46.2 +/- 13 in group II versus 36.2 +/- 6 in group I (p = 0.0002). There was a 24% reduction in the VE/VCO2, from rest to AT in group I, compared to a 16% reduction in group II (p = 0.004). A reduction in the VE/VCO2 from rest to AT less than 16% predicted a VO2max below 14 ml/kg/min with a sensitivity of 60% and a specificity of 93%. CONCLUSIONS: Patients with severe functional impairment have higher values of VE/VCO2 in all exercise stages. A reduction of VE/VCO2 from rest to anaerobic threshold of less than 16% is a high specific predictor of a VO2max below 14 ml/kg/min.


Assuntos
Dióxido de Carbono/análise , Baixo Débito Cardíaco/fisiopatologia , Teste de Esforço , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Valor Preditivo dos Testes
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