RESUMO
The plasma pharmacokinetics and urinary excretion of CM 57755, an H2-receptor antagonist, were studied after administration of single oral doses in a range between a 100 and 700 mg in human volunteers. Pharmacokinetic parameters were calculated model-independent. Absorption of CM 57755 was bimodal and the maximum plasma concentration was reached between 2 and 4 h after dosing. The drug was widely distributed with an apparent volume of distribution between 140 and 200 l. The plasma clearance was between 56 and 69 L/h. The plasma concentrations declined following a monoexponential function with an elimination half-life of 2 h. No modification in the plasma clearance or other pharmacokinetic parameters with these doses was observed. Therefore, a linear pharmacokinetic profile of CM 57755 was proposed. About 40% of the parent drug was unchanged in urine excreted over the 24 h. The drug was compared with cimetidine and ranitidine, the three compounds seemed to exhibit a consistent pharmacokinetic profile.
Assuntos
Antagonistas dos Receptores H2 da Histamina/metabolismo , Niacinamida/análogos & derivados , Administração Oral , Adulto , Antagonistas dos Receptores H2 da Histamina/administração & dosagem , Antagonistas dos Receptores H2 da Histamina/sangue , Humanos , Cinética , Masculino , Niacinamida/administração & dosagem , Niacinamida/sangue , Niacinamida/metabolismoRESUMO
Hypertensives in pregnancy are not so grossly distinct and different from adult hypertensives if reference is made to the underlying arterial anomalies and malformations of the parenchyma and their incidence. It is, however, in this group that the limited way in which the active remnant of parenchyma, once constrained by these anomalies, can compensate for the changes in pressure and volume sensitivity imposed by pregnancy is most evident; these changes may be caused by pyelonephritis of pregnancy (genuine but rare), eclampsia of the primigravida, progressive hypertension in the multigravida, or certain cases of late hypertension, menopausal hypertension, or hypertension as a late result of a simple juvenile eclampsia. This series contains a particularly high percentage (21%) of cases of hypertension due to unilateral renal arterial ischaemia which are curable.
Assuntos
Hipertensão/etiologia , Complicações Cardiovasculares na Gravidez/etiologia , Angiografia , Feminino , Humanos , Hipertensão/patologia , Rim/anormalidades , Rim/patologia , Gravidez , Pielonefrite/complicações , Artéria Renal/anormalidades , Artéria Renal/patologiaRESUMO
The Cardiac Clinic reports its experience of 16 cases having unilateral curative renal surgery for hypertension in the adult, and has found a particularly high incidence (8 per cent of all cases). A study has been made of the lesions in the malformed and dysplastic renal arteries on the one hand, and of the correspondingly ischaemic and atrophic renal parenchyma on the other. Attention is drawn to the cases of unilateral renal atrophy (50 per cent of cases), the commonest involving gross lymphoplasia of congenital arterial origin. The other cases are of stenotic dysplasias, and special points to notice are the spread of the dysplasia towards the parenchyma, the presence of multiple aneurysms which militate towards nephrectomy, and the relative frequency of dysplasia of the intima (2 cases out of 8).
Assuntos
Artérias/patologia , Hipertensão/patologia , Rim/irrigação sanguínea , Rim/patologia , Artéria Renal/patologia , Adulto , Aneurisma/patologia , Atrofia , Feminino , Humanos , Hidronefrose/patologia , Hipertensão Renal/patologia , Hipertensão Renovascular/patologia , Isquemia/cirurgia , Masculino , Pessoa de Meia-Idade , Nefrectomia , GravidezRESUMO
Born in Arles on February 21st 1875, Madame J. C. was the oldest registered human being. She died on August 4th 1997 at the age of 122 years, the record for longevity probably for a long moment. Based on this unique case and a review of the literature, the authors describe the mechanical, physiological and clinical aspects of normal cardiac ageing. The diseases of the elderly which accelerate the process of physiological ageing are then reviewed. With its participation in left ventricular hypertrophy, left atrial dilatation and the increase in valvular stress, the decreased elasticity of the great arteries seems to be the essential factor.
Assuntos
Envelhecimento/fisiologia , Coração/fisiologia , Longevidade/fisiologia , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia , Feminino , HumanosRESUMO
The localisation of a pheochromocytoma is difficult and sometimes hazardous. There are many radiological techniques of varying sensitivity and the risks of hypertensive crises or of cardiovascular collapse are not negligeable (especially during arteriography and venography). Abdominal computerised axial tomography (CAT) would appear to be of considerable value. It gives a very precise localisation without any risk. Three personal cases confirm this opinion. The first case was of a 38 year old man with an extra-adrenal pheochromocytoma localised in the pelvis of the left kidney by CAT (after negative intravenous urography); the second case was of a 54 year old man with a left adrenal pheochromocytoma confirmed on CAT (after 2 negative aortic arteriogrammes and adrenal venography); the third case was of a 39 year old woman with a para aortic pheochromocytoma, diagnosed on CAT (after negative intravenous urography). These three cases bring to 43 the total number of reports of pheochromocytoma localised by abdominal CAT. When this method is compared with intravenous urography and aortic arteriography, abdominal CAT is over three times more sensitive than intravenous urography (90% compared to 26%) and also more sensitive than arteriography (90% compared to 76%). The false negative results on CAT usually involve small tumours (diameter less than 30 mm). The new generation of CAT should reduce these errors. The great advantage of this investigation should change the order of the radiological examinations in the localisation of pheochromocytoma. It would seem logical to carry out an abdominal CAT as soon as biological confirmation of the hypersecretion of catecholamines had been obtained. The other radiological investigations (especially aortic arteriography) should be reserved for cases with negative abdominal CAT.
Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Feocromocitoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Angiografia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Right axial deviation and delay between stimulation and ventricular response was observed during pacing of the apex of the right ventricle in Prinzmetal angina. The degree of deformation of the ventricular complex and the length of this delay appear to be related to the severity of the anginan, the length of the preceding diastolic period and the amplitude of stimulation. This observation demonstrates the presence of conduction defects at the heart of ischaemic myocardium and may explain the failure of prophylactic pacing in Prinzmetal angina complicated by paroxysmal atrioventricular block.
Assuntos
Angina Pectoris Variante/complicações , Angina Pectoris/complicações , Estimulação Cardíaca Artificial , Bloqueio Cardíaco/etiologia , Idoso , Angina Pectoris Variante/terapia , Bloqueio Cardíaco/prevenção & controle , Humanos , MasculinoRESUMO
Analysis of a further series of 125 consecutive unselected adults who were admitted to hospital with hypertension has advanced the study of arterial abnormalities and parenchymal hypoplasia, as demonstrated by selective renal arteriography, further in the direction of the parenchyma. An index of arterioparenchymal thinning is described. The authors list the features and incidence of polar arteries arising from the aorta (46%), polar arteries of non-aortic origin (31%), stenosing dysplasia (26%) and other arterial malformations, as well as biapical hypoplasia (67%), monofocal hypoplasia (37%), and the main types of renal dysgenesis (30%) which they found. The incidence of these abnormalities confirms the previous study of polar arteries arising from the aorta, and gives much more extensive information on the topic of parenchymal hypoplasia in so-called essential hypertension in the adult.
Assuntos
Aorta/anormalidades , Hipertensão/complicações , Rim/anormalidades , Artéria Renal/anormalidades , Adulto , Idoso , Doenças da Aorta/diagnóstico por imagem , Feminino , Humanos , Hipertensão/diagnóstico por imagem , Infarto/complicações , Infarto/diagnóstico por imagem , Rim/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Radiografia , Artéria Renal/diagnóstico por imagemRESUMO
A female patient of 22 with major hypertension was operated upon for a dyspalastic diaphragm stenosis of the right renal artery; she had otherwise a left lower polar aortic artery. The histological study was under-taken on four comparative biopsy specimens. In the aortic polar artery territory, the signs of atrophic dysgenesis were demonstrated: rarefaction and sclerosis of the glomeruli, sclerosing intretitial infiltration. They reproduce exactly the lesions of immature kidneys described by Marshall.
Assuntos
Artérias/anormalidades , Hipertensão/etiologia , Rim/irrigação sanguínea , Obstrução da Artéria Renal/patologia , Adulto , Angiografia , Biópsia , Anormalidades Congênitas/complicações , Feminino , Humanos , Hipertensão Renal/etiologia , Rim/patologia , Obstrução da Artéria Renal/diagnóstico por imagem , Obstrução da Artéria Renal/cirurgiaRESUMO
Results of arterial surveys on the basis of renal arteriograms in 100 consecutive unselected and hospitalized cases of lone arterial hypertension of the adult. Abnormal polar arteries with direct branching from the aorta were observed in 52 cases, combined with a stenosing or parnechymatous arterial anomaly in 7, quite isolated in 45 cases (61.8 percent of 73 cases). The very great incidence of abnormal polar arteries is a fundamental epidemiological datum of lone arterial hypertension of the adult.
Assuntos
Hipertensão Renal , Hipertensão/etiologia , Artéria Renal/anormalidades , Adolescente , Adulto , Idoso , Angiografia , Anormalidades Congênitas/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
During the course of an aorto-femoral bypass in a normotensive young man, an inferior polar artery arising low on the aorta, and supplying the right kidney, was ligated. The limited ischaemia (demonstrated by later arteriography) of the parenchyma at the pole of the kidney was responsible, during the following weeks, for severe hypertension with a raised level of circulating plasma renin, but one that was rapidly treatable. This finding, which was fortuitous but could be ranked as "experimental", demonstrates the important role of abnormal polar arteries and of the renal parenchyma in human arterial hypertension. Such may, for example, be the underlying disorder in cases of hypertension after the transplantation of a kidney with an "uncontrolled" polar artery arising from the aorta, for the so-called "pyelonephritic" hypertension in pregnant patients caused by defective blood supply in an inter-pyramidal artery and corresponding subcortical infarction of the kidney, and for curing hypertension in the adult when isolated polar arteries arising from the aorta and stenosed at their point of origin are reimplanted into the main renal artery.