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Biomedical subjects

S Oren

Publications and source records attributed to S Oren.

52 records · Page 3Linked to original sources
PubMed1989

Sex differences in cardiac adaptation to essential hypertension.

Left ventricular functional and structural adaptations to mild essential hypertension were assessed by 2D-guided M-mode echocardiography in a population of premenopausal and postmenopausal women (n = 29) who were matched with the same number of men with regard to mean arterial pressure, age and race. Premenopausal women had a thinner posterial wall (P less than 0.05), a smaller left ventricular systolic and diastolic diameter, and a smaller left ventricular mass than men with the same level of arterial pressure. Left ventricular performance indices, ejection fraction, velocity of circumferential fibre shortening, and the ratio of the end-systolic wall stress to the end-systolic volume index (a load-insensitive contractility index) were higher in women than in men. These sex differences were most pronounced before the menopause and tended to disappear thereafter. We conclude that in the presence of the same level of arterial pressure, women have smaller left ventricular dimensions and enhanced ventricular performance compared with men. These differences in cardiac adaptations between the genders may account for the lower risk of cardiovascular morbidity and mortality in premenopausal women with essential hypertension.

Adaptation, Physiological↗
PubMed1989

Perirenal and renal subcapsular haematoma as presenting symptoms of polyarteritis nodosa.

Two young men, were hospitalized due to acute massive blood loss with left abdominal flank pain. In both cases renal angiography showed signs of a haemorrhagic event in the left kidney, perirenal in one and subcapsular in the other. Microaneurysms indicated a diagnosis of polyarteritis nodosa, supported by renal biopsy in one case. Renal haemorrhage is an infrequent presentation of polyarteritis nodosa. Furthermore, one patient suffered also from familial Mediterranean fever, and is the fifth reported case with this combination of diseases.

Adult↗
PubMed1989

The antihypertensive effect of atenolol and bopindolol in the elderly.

The antihypertensive efficacy and tolerability of two betablockers: atenolol and bopindolol, was compared in a group of 30 elderly subjects aged 64.8 +/- 4.6 years. The daily dose of the two agents was relatively low. Atenolol 50-100 mg and bopindolol 0.5-1.0 mg sufficed to cause reduction of DBP to the target of less than or equal to 95 mm Hg, when applied as monotherapy. This was achieved in 75% of cases with bopindolol and in 93% of cases with atenolol. Atenolol, 50-100 mg/dd, lowered blood pressure from 173.7 +/- 13.2/103.7 +/- 3.0 (weekly) to 155.5 +/- 16.5/86.5 +/- 8.2 mm Hg (week 12) (P less than 0.005) while bopindolol, 0.5-1.0 mg, lowered blood pressure from 171.6 +/- 11.3/104.1 +/- 3.6 to 158.7 +/- 20.9/86.1 +/- 6.0 mm Hg (P less than 0.005). Heart rate was reduced from 80.5 (week 4) to 66.7 +/- 7.3 (week 12) by atenolol (P less than 0.0001), and from 83.7 +/- 11.8 (week 4) to 71.1 +/- 7.5 (week 12) by bopindolol (P less than 0.0001). Between treatment differences: comparisons yielded P values which were not sufficiently low to reject the null hypothesis of no difference between the two treatments. Well-being and short-term memory were not affected by either agent and tolerability of both drugs was good. These findings demonstrate that both bopindolol and atenolol are useful agents for control of hypertension in the elderly.

Adrenergic beta-Antagonists↗
PubMed1988

Systemic and regional hemodynamic and humoral effects of nitrendipine in essential hypertension.

The hemodynamic effects of 3 months of nitrendipine therapy were evaluated in 14 patients with mild to moderate essential hypertension. Nitrendipine reduced systolic and diastolic pressures from 145 +/- 4/95 +/- 3 to 119 +/- 3/78 +/- 2 mm Hg, respectively, (p less than 0.001) through a fall in total peripheral resistance index (46 +/- 4 to 34 +/- 3 units/m2, p less than 0.001) without associated reflex cardiac stimulation. This antihypertensive effect was related directly to the height of pretreatment arterial pressure (r = -0.67, p = 0.006) but not to age or pretreatment plasma renin activity. Renal and forearm blood flow increased, vascular resistance decreased, and glomerular filtration rate remained stable. In addition, nitrendipine reduced left ventricular mass index (133 +/- 7 to 116 +/- 5 g/m2, p = 0.003) and wall thickness, changes that were accompanied by improvement in diastolic as well as systolic (ejection fraction and fractional fiber shortening rate) left ventricular functions. Intravascular volume did not expand with reduction in pressure. This study provides new information concerning the long-term hemodynamic effects and associated echocardiographic changes with nitrendipine. It also provides the first regional hemodynamic data in essential hypertensive patients detailing forearm and splanchnic changes and renal blood flow increase during prolonged treatment.

Aged↗
PubMed1988

Left ventricular hypertrophy and antihypertensive therapy.

Cardiac adaptation to long-standing arterial hypertension consists of left ventricular hypertrophy (LVH), usually of the concentric type, i.e. an increase in wall thickness at the expense of chamber volume. LVH can no longer be considered only as a simple adaptive myocardial process; it drastically increases the risk of sudden death and cardiovascular morbidity and mortality, irrespective of the levels of arterial pressure. Patients with LVH have more premature ventricular contractions than patients without LVH or normotensive subjects, which indicates that LVH per se increases ventricular ectopic activity. Antihypertensive therapy should not only lower blood pressure, but also prevent or improve end-organ damage and therefore allow left ventricular mass to regress. Although they lower blood pressure, certain antihypertensive agents such as the thiazide diuretics and arteriolar dilators (hydralazine, minoxidil) have little or even a detrimental effect on LVH. In contrast, other agents such as angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, antiadrenergic drugs, and certain calcium antagonists decrease left ventricular mass in parallel with arterial pressure. Recent evidence has shown that a decrease in left ventricular mass induced by certain antihypertensive drugs suppresses ventricular ectopic activity by 85%. In contrast, left ventricular mass and ventricular ectopic activity remain unchanged or may even increase in patients treated with diuretics. It is not known whether the risk of sudden death can be decreased and the ominous prognosis of LVH altered by such specific antihypertensive therapy.

Antihypertensive Agents↗
PubMed1987

The dilemma in prenatal diagnosis of idiopathic microcephaly.

It is estimated that 20 to 35 per cent of idiopathic microcephaly is hereditary. Common practice dictates that after the birth of such a case, subsequent pregnancies should be monitored ultrasonographically in order to facilitate early antenatal diagnosis, and thus genetic counselling. Two cases are reported to indicate the difficulties encountered. In case 1 head growth appeared to be normal until the 20th week of gestation and then slowed down to 31 cm at birth. In case 2 head growth proceeded normally until the 28th week of gestation; at birth it was 32 cm and over the succeeding months became markedly microcephalic. The accuracy of various ultrasonographic techniques is reviewed, and the limitations are discussed. In the light of these findings it is concluded that reliable prenatal diagnosis of hereditary microcephaly is not available as yet.

Cephalometry↗
PubMed1987

Extreme hypermagnesemia due to ingestion of Dead Sea water.

We describe 3 patients who developed extreme hypermagnesemia due to ingestion of water of the Dead Sea, which would have been fatal were it not for the protective effects of the accompanying hypercalcemia. We emphasize the clinical features of this condition and the importance and effectiveness of early hemodialysis as the main modality of treatment.

Aged↗
PubMed1985

Does 1,25-dihydroxyvitamin D participate in the regulation of hormone release from endocrine glands?

The presence of receptors for 1,25-dihydroxyvitamin D3 in the pituitary, pancreas, testis, and ovary has raised the question of a possible direct role for 1,25-dihydroxyvitamin D (1,25(OH)2D) in the regulation of hormone synthesis and secretion. To evaluate this problem, six children with the syndrome of resistance to 1,25(OH)2D with rickets and alopecia underwent dynamic tests of insulin, TSH, PRL, GH, and testosterone secretion. Oral glucose loading resulted in normal glucose curves, subnormal peak insulin responses of 12-20 microU/ml in three hypocalcemic patients, and normal peak serum insulin values of 30-40 microU/ml in two normocalcemic patients. Basal serum, TSH, PRL, T4, and T3 concentrations were normal in all patients. Peak serum TSH values after TRH were 11-17 and 16-32 microU/ml in the hypo- and normocalcemic patients, respectively. The PRL response to TRH stimulation in either hypocalcemic or normocalcemic patients was normal [mean 26.2 +/- 5.1 (SD) ng/ml]. Peak serum GH levels were greater than 8 ng/ml in all five patients studied after one or more of the various stimuli. Serum testosterone concentrations after hCG stimulation were normal in the three patients studied (4.1-8.0 ng/ml). Thus, in children with resistance to 1,25(OH)2D, we could find no significant abnormalities in hormone secretion from the pituitary, pancreas, and testis apart from those presumably due to the hypocalcemia itself.

Calcitriol↗
PubMed1985

Mitral valve prolapse. Quantitative analysis and long-term follow-up.

Forty-two patients with systolic posterior motion of the mitral valve on M-mode echocardiogram were reevaluated after a mean clinical follow-up of 6.7 years and an echocardiographic follow-up of 5.1 years. A new method for quantitation of mitral valve prolapse (MVP) is presented. A straight line (A) was drawn connecting the site of posterior leaflet motion with the D point of the subsequent diastole. A vertical line (B), termed "the degree of MVP," was drawn from the site of maximal MVP to line A. The degree of MVP was then correlated with various clinical and ECG parameters and with the presence of complications. Measurements could be taken in 21 patients; the mean degree of MVP increased from 5.9 +/- 2.1 to 7.1 +/- 2.9 mm (P less than 0.01), and mean left atrial size increased from 3.0 +/- 0.5 to 3.5 +/- 0.8 cm (P less than 0.01). No correlation was found between the degree of MVP and symptoms, auscultatory findings or the presence of complications. There were no deaths and in none was life-threatening arrhythmia documented. The complications we encountered were endocarditis in five patients, transient ischemic attacks in two and cardiac arrest during surgery in one. We conclude that 1) the degree of MVP can be measured by M-mode echocardiography; 2) there seems to be no correlation between the degree of MVP and the patient's clinical state; 3) complications in MVP are rather frequent; and 4) left atrial size and degree of MVP tend to increase with time, which may indicate a progressive nature of the disease.

Adolescent↗