Multidimensional assessment of the elderly.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to M Ibarra.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
In preoperative use, the administration of 2 mg of lormetazepam perorally to patients no doubt abnormally nervous in anticipation of a forthcoming operation has proved to be an excellent inducer of sound sleep. In postoperative use, a dose of 2 mg of lormetazepam has a positive effect compared with the placebo, both on sleep inducement and on quality and duration of sleep. However, the results of a small series of twelve patients indicate that for recently operated adults the administration of 3 mg of lormetazepam may be recommended. Indeed we believe 4 mg might not be excessive.
Heterogeneity of vascular alpha 1-adrenoceptor subtypes has been revealed by pharmacological and molecular biology studies (i.e., alpha 1A-, alpha 1B-, and alpha 1D-adrenoceptors). The alpha 1D-adrenoceptor subtype is predominantly involved in the contraction of a variety of vessels and its role in the control of blood pressure has been suggested, a phenomenon probably related to aging. Recent advances in the use of young pre-hypertensive rats and adult spontaneously hypertensive rats with one kidney and Grollman-type renal hypertension suggest vascular alpha 1D-adrenoceptor involvement in the increased blood pressure. The possible role of alpha 1D-adrenoceptors in the genesis/maintenance of hypertension is discussed in this review.
BACKGROUND: It has recently been reported that chloroethylclonidine (CEC) elicited contraction in tail arteries (alpha(1A)-adrenoceptors) and aorta (alpha(1D)-adrenoceptors) from normotensive and spontaneously hypertensive rats (SHR). This study investigated the relationship between CEC-induced contraction and the role of protein kinase C (PKC) and extracellular Ca(++) influx in tail arteries and aorta from Wistar Kyoto rats (WKY). METHODS: Time-course of CEC-induced contraction in endothelium-denuded arteries from Wistar, WKY, and SHR rats was evaluated. In WKY arteries, calphostin C (1 x 10(-6) M) and nitrendipine (1 x 10(-6) M) were used to determine the role of PKC and extracellular Ca(+1) in the contractile response to CEC, respectively. RESULTS: Chloroethylclonidine (1 x 10(-4) M) elicited contraction in tail arteries and aorta from normotensive and hypertensive rats. Maximal response to CEC was similar in tail arteries among strains (approximately 30% of norepinephrine effect), while in aorta CEC elicited a higher contraction in WKY and SHR than in Wistar (59, 86, and 18% of norepinephrine effect, respectively). CEC-elicited maximal contractile responses were reached in 5 min in tail arteries and in 30-45 min in aorta irrespective of the rat strain, suggesting that different intracellular signaling pathways are involved in the contractile response to CEC in these arteries. In WKY tail arteries, calphostin C and nitrendipine blocked CEC-induced contraction while in aorta nitrendipine, but not calphostin C, inhibited CEC action. CONCLUSIONS: This study confirms marked strain-dependent differences in rat aorta responsiveness to CEC and suggests a central role for PKC in response to CEC in tail arteries and for extracellular Ca(+1) influx in aorta.
BACKGROUND: Stimulation of central 5-HT(1A) receptors produces bradycardia and diminishes blood pressure in conscious or anesthetized rats. Our objective was to investigate the effects on blood pressure and heart rate of the partial 5-HT(1A) receptor agonist and selective alpha1D-adrenoceptor antagonist BMY 7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl] ethyl]-8-azaspiro [4.5] decane-7,9 dione hydrochloride) compared to the full 5-HT(1A) receptor agonist 8-OH-DPAT (8-hydroxy-dipropylamino tetralin) in adult anesthetized rats. METHODS: Male Wistar rats of 6 months of age were exposed intravenously (i.v.) to increasing doses of BMY 7378 or 8-OH-DPAT in the absence and presence of WAY 100635. Blood pressure and heart rate were continuously recorded. RESULTS: BMY 7378 induced a decrease in blood pressure with no apparent change in heart rate compared to basal values, while 8-OH-DPAT decreased both hemodynamic parameters. BMY 7378 hypotensive effect was antagonized by the selective, silent 5-HT(1A) receptor antagonist WAY 100635 (N-[2-[4-(2-methoxyphenyl)-1-piperazinyl] ethyl]-N-(2-pyridinyl) cyclohexanecarboxamide trihydrochloride). However, a remnant yet significant hypotensive effect was not blocked by the antagonist. In contrast, 8-OH-DPAT actions were completely blocked by WAY 100635. CONCLUSIONS: Data suggest that BMY 7378 cardiovascular effects are related to activation, as a full agonist, of central 5-HT(1A) receptors in adult rats; however, participation of other systems such as vascular alpha1-adrenoceptors in cardiovascular function is suggested.
Explore the source record for details and available documents.
Our group initiated a program of coronary angioplasty (CA) in patients with symptomatic one vessel disease, or multivascular lesions with a critical "culprit" stenosis. In a 16 month period we have performed CA of 28 lesions in 25 patients (20 men) with a mean age of 54 +/- 10 years. Stable angina was diagnosed in 14 patients, unstable angina in 7, and post-myocardial infarction residual angina or stenosis in 4 patients treated with streptokinase. Successful dilatation was obtained in 23 (82.1%) of 28 stenotic segments, reducing the stenosis from 90 +/- 8% (range 70-100) to 9 +/- 12% (range 0-30; p less than 0.00001). In 4 cases with total occlusion, dilatation was not obtained, and in one case the procedure was complicated by fatal brain embolism. There were 4 complications due to coronary occlusion or spasm, all of them resolved during CA without sequelae. The 20 cases with primary success have been followed during an average of 8.6 months. In three cases (15%) restenosis was detected; two of them underwent surgery, and CA was repeated successfully in the other. Disappearance of myocardial ischemia was confirmed in 14 patients, and functional improvement in the other three. In conclusion, CA is an effective and relatively safe therapeutic alternative in different clinical forms of coronary heart disease with a single vessel stenosis, or in selected cases of multivascular lesions with a critical stenosis.
Between August 1988 and October 1993, 19 patients with native aortic coarctation were subjected to transluminal percutaneous balloon angioplasty, 12 of which were men (63.1%) and 7 were women (36.9%), with an average age of 22 +/- 7.7 years (r- 16 to 52), all of whom suffered from arterial hypertension at the time of the procedure, and a systolic pressure of 190 +/- 32.2 mmHg (r- 160 to 240). The gradient of the systolic pressure (GPS) was 77 +/- 0.9 mm, the average diameter of the balloon catheters that were used was 18.3 +/- 1.7 mm (r- 15 to 20). For all the patients, the procedure was carried out under local anesthesia and the usual Seldinger technique. After carrying out the procedure, the GPS as well as the blood pressure dropped to 5.0 +/- 4.1 mmHg and 130 +/- 20.6 mmHg, respectively. In similar manner, the enlargement of the ring displayed an increase of 4.2 +/- 0.9 to 14.1 +/- 1.6 mm. There were no complications in any of the procedures. During the follow-up, 11 patients were catheterized again in a period of 24.7 +/- 12.6 months (r- 10 to 48) with GPS of 5 +/- 2 mmHg. Besides, an increase of 15.4 +/- 1.2 mm in the ring's diameter was observed. In these patients, there was no evidence of the aneurysms at the dilatation site. Of the rest of the patients under control, 17 of whom have been able to maintain normal blood pressure without medical treatment, and only two required low dosages of antihypertensive treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
From October 1991 to October 1993, a total of 205 patients with rheumatic mitral stenosis (178 female, 27 male, mean age 38 years, range 17-72) underwent percutaneous transvenous mitral commissurotomy (PTMC), 138 with the Inoue balloon and 67 with double balloon-catheter techniques. Mitral regurgitation (MR) was detected in 10% of the cases prior to the procedure, and 37% after PTMC (p < 0.05), grade I in 45 patients (22%), grade II in 24 (12%), grade III in 4 (2%), and grade IV in 3 (1.5%) cases (p = 0.003, 0.002, N.S. and N.S., respectively. In 40% of the total group (83/205) there was no new or worsening MR; in 26.8% of the cases (55/205) new MR appeared (p = 0.004); in 23% (47/205) MR increased one grade (p = 0.002) and in 9.7% (20/205) two or more grades. The comparative incidence of MR was 40.5% (56/138) with the Inoue balloon, and 16.4% (11/67) with the double balloon technique (p = 0.03); the severity of MR was grade I in 27% vs 9% (p = 0.001), grade II in 9.4% vs 6% (p = 0.05), grade III in 2.1% vs 1.5% (N.S.), and grade IV in 2.1% vs 0% (N.S.). Only the presence of commissural calcification and echo-score > 8 points were found as independent predictors of severe MR. In conclusion, mild and moderate MR occur frequently after PTMC, with significantly greater incidence using the Inoue technique. Severe MR following PTMC is much less frequent, and the comparative incidence is somewhat greater with the Inoue balloon, though the difference is not significant.
The 5-HT1A ligand, spiroxatrine, displays very low affinity for alpha 1-adrenergic binding sites and a relatively high affinity for alpha 2-adrenergic binding sites. Nonetheless, recent functional studies indicate that spiroxatrine is a potent antagonist of the alpha 1-adrenoceptor mediating contraction in the rat isolated aorta. On the basis of the widely studied heterogeneous interaction of drugs with alpha-adrenoceptors in several experimental models, the present study was designed to analyze the alpha-adrenoceptor antagonist properties of spiroxatrine in the pithed rat. Animals were prepared for recording of arterial blood pressure and intravenous (i.v.) administration of drugs. Norepinephrine and the alpha 1- and alpha 2- adrenoceptor agonists methoxamine and clonidine, respectively, elicited pressor responses in a dose-related fashion. Spiroxatrine (1 mg/kg, i.v.) produced a moderate--but significant--rightward displacement of the dose-response curves to all agonists. The present data lead us to suggest that, though spiroxatrine exhibits alpha 1- and alpha 2-adrenoceptor antagonist properties in the pithed rat, its potency does not seem to correlate with that found in rat aorta. The potential involvement of alpha 1-adrenoceptor subtypes is discussed.
In 110 adult selected patients, 87.1% female (average age 38.2 years, range 16-72) with symptomatic, severe mitral stenosis eligible for surgery, we performed balloon catheter transvenous mitral commissurotomy (BCTMC) as alternative treatment. Inoue's catheter was utilized in 80 cases (72.7%), and the double-balloon technique in 30 (27.3%). The procedure was successful in 102 patients (92.7%, 2nd attempt in 5 cases), with optimal results in 96 (87.3%); and it was unsuccessful in one patient for a technical difficulty. Complications occurred in 3 cases due to perforation of a cardiac chamber (2.7%); and 4/106 patients developed severe mitral insufficiency (3.8%). The mitral valve area increased from 1.09 +/- 0.27 to 2.6 +/- 0.87 cm2 (p < 0.0001); the diastolic mitral gradient decreased from 18.9 +/- 5.9 to 3.6 +/- 2.8 mmHg (p < 0.0001); similar reduction was obtained in mean left atrial pressure from 26.2 +/- 6.5 to 12.5 +/- 4.2 mmHg (p < 0.0001), and mean pulmonary artery pressure from 38 +/- 17 to 26.2 +/- 10.4 mmHg (p < 0.005). New mitral insufficiency appeared or increased in more of one grade in 12/106 patients (11.3%), and it was not detectable in 86/106 patients. During long-term follow-up (average 10.4 months, range 5 to 24), all patients (100 cases) improved their functional class (83.1% asymptomatic), and maintained their 2D echocardiographic mitral valve area. In conclusion BCMTC is the treatment of choice for selected cases of acquired symptomatic mitral stenosis, with immediate and long term results comparable to surgical commissurotomy.
This investigation was performed to determine whether droperidol interacts with 5-hydroxytryptamine (serotonin) receptors in the rat aorta. Droperidol caused concentration-dependent vasorelaxation in endothelium-intact and endothelium-denuded aortic rings precontracted with noradrenaline or 5-hydroxytryptamine. Conversely, the contractile effect of prostaglandin F2 alpha was not affected by droperidol. Pretreatment with propranolol, brompheniramine and atropine (10(-6) M each) did not alter the relaxant effects of droperidol. In addition, droperidol shifted the 5-hydroxytryptamine and noradrenaline concentration-response curves to the right in an apparently competitive manner. However, prazosin did not modify the concentration-response curve to 5-hydroxytryptamine, which is consistent with the hypothesis that the latter has an intrinsic efficacy for non-alpha 1-adrenoceptors. These results strongly suggest that a direct arterial endothelium-independent relaxant action of droperidol can be attributed to a 5-hydroxytryptamine receptor-blocking property and support its vascular alpha-adrenoceptor-blocking effect.