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T Rosenthal

Publications and source records attributed to T Rosenthal.

At least 145 records · Page 8Linked to original sources
PubMed1987

Renovascular hypertension in spontaneous hypertensive rats: an experimental model of renal artery stenosis superimposed on essential hypertension.

Renovascular hypertension superimposed on essential hypertension, a condition encountered in the elderly, was studied. An experimental animal model consisting of a two-kidney one-clip Goldblatt preparation in the spontaneous hypertensive (SHR) rat, that would simulate this condition, was designed. A 0.25 mm silver clip was placed on the left renal artery of SHR male rats. The same procedure performed on WKY rats served as control. All experiments were performed on low, normal, and rich sodium diet. Systolic blood pressure (BP) was measured by tail-cuff method. Plasma renin concentration (PRC) was determined before and after clipping of the renal artery. Results were as follows: Mean systolic BP increased significantly in clipped rats fed with normal and rich sodium diets. SHR showed an increase from 144 +/- 3 (mean + s.e.m.) to 168 +/- 3 mmHg, and WKY rats showed an increase from 120 +/- 2 to 139 +/- 5 mmHg. There was a two- to threefold rise in PRC. A low-salt diet given prior to clipping prevented the appearance of renovascular hypertension despite a significant rise in PRC. We concluded that renal artery narrowing plays a significant role in the rise of BP in the basically essential type of hypertension.

Animals↗
PubMed1987

Exercise testing in juvenile borderline hypertension.

Exercise testing has emerged as an important method for improved evaluation of the cardiovascular system. However, juvenile patients presenting resting borderline hypertension have not been extensively studied. Therefore, this study evaluated the response to exercise in this group of patients. Nine hundred men aged 16 to 29 years performed a multistage near-maximal exercise test. The control group consisted of 338 age- and weight-matched, asymptomatic, healthy, normotensive individuals. Mean physical working capacity (+/- SD) was 129 +/- 28 W (82 +/- 18% of the normal according to our standardization) in the hypertension group, and 153 +/- 29 W (102 +/- 18%) in the control group (P less than 0.001). Mean systolic blood pressures at termination of exercise were 181 +/- 25 and 164 +/- 25 mm Hg in the hypertensive and the control groups, respectively; the mean diastolic values at termination of exercise were 49 +/- 32 and 32 +/- 29 mm Hg, respectively. The magnitude of the changes in blood pressure from rest to near-maximal values was smaller in the borderline-hypertensive individuals demonstrate a clear hypertensive pattern of reaction to physical activity, thus emphasizing the importance of exercise testing as part of the routine workup of such patients. The relationship between borderline hypertension and the risk of myocardial events has been established, and early hygienic or even pharmacological measures are necessary.

Adolescent↗
PubMed1986

[Pheochromocytoma].

Explore the source record for details and available documents.

Adrenal Gland Neoplasms↗
PubMed1986

Synthesis of 19-noraldosterone, a potent mineralocorticoid.

19-Noraldosterone has been prepared for biological re-evaluation through an extension of a recent synthesis of 19-hydroxyaldosterone: 21-hydroxy-6 beta,19-epoxy-4-pregnene-3,20-dion-20-ethylene ketal-18,11 beta-lactone (1a) was acetylated and then reduced with zinc-acetic acid-isopropanol to the 19-ol 2b. Treatment with sodium acetate transposed the double bond into conjugation, and 2a thus obtained was oxidized with pyridinium chlorochromate to the 19-oxo compound 3. Decarbonylation to the 19-nor lactone 4 was effected by heating with alkali. Protection of the C-3 carbonyl was achieved by ketalization and the resulting mixture of the 5-ene and 5(10)-ene ketals 5 was reduced with DIBAH to the corresponding mixture of the hemiacetals 6. Acid hydrolysis of the latter afforded 19-noraldosterone (7), accompanied by the 18,21-anhydro ketal 8. 19-Noraldosterone in the solid state exists in the cyclic form 7b, which appears to be also the predominant isomer present under conditions of mass spectrometry. [1H]NMR indicates that in chloroform 19-noraldosterone exists mostly as an equilibrium mixture of structures 7a and 7b. Sodium periodate oxidation furnished the gamma-etiolactone 9, confirming the 17 beta configuration in 7.

Aldosterone↗
PubMed1986

Captopril as a replacement therapy in hypertension improving quality of life--a multicentre study.

A multicentre study was undertaken to determine whether side effects induced by hypotensive drugs could be reduced by replacement with low dose captopril. There were 100 patients on combinations of drugs, including diuretics, beta-blocking agents, methyldopa, clonidine and vasodilators. A questionnarie to obtain information on quality of life was completed by the patients. Each patient had major drugs, possibly responsible for side effects, withdrawn. Captopril was added at an initial dose of 12.5 up to 25 mg b.i.d. and titrated to a maximum of 50 mg t.i.d., until the blood pressure was equal to or lower than the level on entry into the study. Blood pressure was measured every two weeks and questionnaries were completed a number of times during the treatment period and scored at random, not in chronological order. A marked drop in blood pressure was obtained: mean systolic blood pressure went down from 173.4 +/- 2 to 154.5 +/- 2 mm Hg and diastolic blood pressure dropped from 104.5 +/- 11 to 9l.5 +/- 12 mm Hg. Neither tachycardia nor orthostasis was observed. Side effects, including inability to concentrate, nightmares, dizziness and sexual dysfunction, were reduced in 36% of the patients. Captopril itself produced no significant additional adverse reactions. It is concluded that captopril is a safe and effective drug, which can replace antihypertensive drugs that have deleterious side effects.

Adult↗
PubMed1986

The hypotensive effect of nisoldipine in renovascular hypertensive rats.

The effect of nisoldipine, a new calcium antagonist, on rats with renovascular hypertension was evaluated. Eight one-kidney, one clip hypertensive rats (1K, 1C rats) given nisoldipine 10 mg/kg for 4 weeks were compared with eight 1K, 1C hypertensive control rats. Fifteen other rats underwent sham-operation (right nephrectomy, no clip), of which eight received nisoldipine in the same dosage. A significant decrease in systolic blood pressure (BP) was achieved in the nisoldipine groups: from 154 +/- 4 to 107 +/- 7.5 mmHg in the 1K, 1C group (P less than 0.005) and from 117 +/- 4.2 to 89 +/- 5.4 mmHg in the sham-operated rats (P less than 0.01). The significant decrease in BP was maintained for only 6 days, but did not rise markedly throughout the entire study. Four 1K, 1C control rats died before term, two after 14 days and two after 20 days. There was no significant change in the pulse rate. Sugar and cholesterol levels in the nisoldipine groups remained constant. Nisoldipine caused a natriuresis without kaluresis in both groups: sodium excretion in the 1K, 1C rats increased from 0.25 +/- 0.05 to 2.32 +/- 0.2 mmol/day, and from 0.34 +/- 0.1 to 1.85 +/- 0.15 mmol/day in the sham-operated rats. A slight decrease in aldosterone levels in the 1K, 1C rats was observed. It appears that the combination of both natriuretic and vasodilatory effects during nisoldipine treatment results in a favourable hypotensive response in 1K, 1C hypertensive rats.

Animals↗
PubMed1986

The effect of sodium restriction in renovascular hypertension.

Six patients with angiographically proven renal artery stenosis were given a low salt diet, consisting of 10 mEq sodium per day for 4-6 days. Five patients showed a remarkable decrease in blood pressure (BP), from 169 +/- 12/107 +/- 4 to 131 +/- 12/84 +/- 5 mmHg, despite a rise in renin level. The decrease in BP was paralleled by a decrease in urinary sodium excretion. Restoration of the regular diet caused immediate elevation of blood pressure. We conclude that severe sodium restriction can reduce blood pressure in patients with renovascular hypertension.

Adult↗
PubMed1986

Hypertensive crisis associated with nifedipine withdrawal.

A 71-year-old hypertensive patient experienced a severe hypertensive crisis. His blood pressure was 300/200 mm Hg three days after nifedipine therapy was discontinued. He had been taking nifedipine together with methyldopa. During five months on the combined treatment, his blood pressure had not risen higher than 170/100 mm Hg. A severe hypertensive crisis following abrupt nifedipine withdrawal has not been previously reported, to our knowledge. We recommend that caution be used when abrupt cessation of nifedipine therapy is considered in the treatment of hypertension.

Aged↗
PubMed1985

Long-acting nifedipine in moderate and severe hypertensive patients with serious concomitant diseases.

Long-acting nifedipine tablets were given to 47 severely and moderately hypertensive patients with renal insufficiency, cardiovascular, cerebrovascular, and peripheral vascular disease, diabetes mellitus, asthma, and systemic lupus erythematosus. Nifedipine substituted vasodilators (n = 22), was added to beta blockers and thiazides (n = 14), and was used alone (n = 11). In all three groups blood pressure was significantly reduced without aggravation of angina pectoris, intermittent claudication, cerebrovascular disease, or renal failure. Side effects were mild and transient. We found nifedipine tablets convenient and safe, as well as efficacious in patients with serious conditions.

Adult↗
PubMed1985

Asymptomatic long-standing idiopathic hypoparathyroidism discovered following delivery of a healthy infant.

A case of long-standing idiopathic hypoparathyroidism that remained asymptomatic during pregnancy is described in a 25-year-old primipara. Clinical signs including carpopedal spasm, convulsions, and acute psychosis developed after the patient gave birth to a healthy infant. In contrast to previous reported cases, no signs of osteitis fibrosa cystica were found in the infant. This is believed to be the first such case described.

Adult↗