Publications by authors named "Ayala D"

Previous results have indicated that valsartan administration at bed-time, as opposed to upon wakening, improves the diurnal/nocturnal ratio of blood pressure (BP) toward a normal dipping pattern, without loss of 24 h efficacy. This ratio is characterized by a progressive decrease with aging. Accordingly, we investigated the administration time-dependent antihypertensive efficacy of valsartan, an angiotensin blocking agent, in elderly hypertensive patients.

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Previous results have indicated that valsartan administration at bedtime as opposed to on wakening improves the diurnal/nocturnal ratio of blood pressure without loss in efficacy and therapeutic coverage. We hypothesized that increasing this ratio could reduce microalbuminuria. We conducted a prospective, randomized, open-label, blinded endpoint trial on 200 previously untreated nonproteinuric patients with grade 1 to 2 essential hypertension, assigned to receive valsartan (160 mg/d) as a monotherapy either on awakening or at bedtime.

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Aspirin is a potent antioxidative agent that reduces vascular production of superoxide, prevents angiotensin II-induced hypertension, and induces NO release. Low-dose aspirin administered at bedtime, but not on awakening, has also been shown to reduce blood pressure, possibly enhancing the nocturnal trough in NO production. Because endothelium-dependent vasodilation is blunted through a decrease in NO release in non-dipper compared with dipper patients, we compared the administration time-dependent influence of aspirin on ambulatory blood pressure in dipper and non-dipper hypertensive subjects.

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Patients with resistant hypertension present high prevalence of a non-dipper blood pressure pattern. Recent results indicate that non-dipping is related partly to the absence of 24-hour therapeutic coverage in patients treated with single morning doses. Accordingly, we investigated the impact of treatment time on the blood pressure pattern in 700 patients with resistant hypertension on the basis of clinic measurements who were studied by 48-hour ambulatory monitoring.

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Purpose Of Review: Many studies show that the extent of the nocturnal blood-pressure decline is deterministic of cardiovascular injury and risk. Accordingly, there is growing interest in how to tailor the treatment of hypertensive patients according to their circadian blood-pressure pattern.

Recent Findings: Differences in efficacy depending on the time of day of drug administration lead to differences in effects of antihypertensive drugs on the nocturnal decline relative to the diurnal mean of blood pressure.

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Studies based on conventional office blood pressure (BP) measurements concluded that both maternal age and parity have significant effects on BP during pregnancy. Previous results have also indicated predictable trends of BP variability with gestational age. Accordingly, we have evaluated possible differences in the circadian pattern of ambulatory BP as a function of parity, maternal age, and stage of gestation in normotensive women who were systematically studied by ambulatory BP monitoring during their pregnancies.

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A thermochemical a rather simple experimental technique method, is used to determine the enthalpy of the formation of 3,6-dibutanoic-1,2,4,5-tetroxane. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6-311G basis set level.

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Hypertension is a frequent cardiovascular risk factor in liver transplant recipients. The usefulness of ambulatory blood pressure monitoring (ABPM) in these patients is unknown. This study was aimed at evaluating the circadian rhythms of blood pressure in liver allograft recipients.

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We have designed and synthesized a new series of arylpiperazines V exhibiting high 5-HT(1A)R affinity and selectivity over alpha(1)-adrenoceptors. The new selective 5-HT(1A)R ligands contain a hydantoin (m = 0) or diketopiperazine (m = 1) moiety and an arylpiperazine moiety separated by one methylene unit (n = 1). The aryl substituent of the piperazine moiety (Ar) consists of different benzofused rings mimicking the favorable voluminous substituents at ortho and meta positions predicted by 3D-QSAR analysis in the previously reported series I.

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Objectives: Several studies have indicated that the use of the 24-h mean of blood pressure, mainly using reference thresholds derived from the general non-pregnancy practice, does not provide a proper test for diagnosis of hypertension in pregnancy. This prospective study examines previously derived reference thresholds for the 24-h, diurnal, and nocturnal mean of blood pressure as potential screening tests for the diagnosis of hypertension in pregnancy.

Methods: We studied 235 normotensive and 168 hypertensive pregnant women, who provided 2430 blood pressure series sampled every 20 min during the day and every 30 min at night for 48 consecutive hours once every 4 weeks from the first obstetric visit until delivery.

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The free radical nitric oxide (NO*) is involved in a variety of diverse biological processes from acting as a vasodilator in the cardiovascular system to being the rate-limiting component in the production of peroxynitrite (ONOO-), a contributor to neurodegenerative disorders such as multiple sclerosis (MS). Uric acid (UA), the end product of purine metabolism in humans and a selective inhibitor of toxic reactions attributed to radicals formed by the interaction of ONOO- and CO2, is generally low in MS patients. We investigated the relationship between serum ONOO-, CO2, and UA in MS patients and normal controls by comparing the circadian characteristics of the NO* metabolites nitrite/ nitrate (NO), CO2, and UA.

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Previous studies have shown that a single nighttime dose of standard doxazosin, an alpha-adrenergic antagonist, reduces blood pressure (BP) throughout the 24 h. We investigated the administration-time-dependent effects of the new doxazosin gastrointestinal therapeutic system (GITS) formulation. We studied 91 subjects (49 men and 42 women), 56.

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Objectives: Previous reports on the effects of continuous positive airway pressure (CPAP) therapy for obstructive sleep apnoea (OSA) on blood pressure has shown contradictory results. Accordingly, we have investigated the effects of CPAP on blood pressure and on the potential reversal of the diagnosis of hypertension in patients with OSA evaluated repeatedly by ambulatory blood pressure monitoring.

Methods: We studied 122 patients (104 men and 18 women), 55.

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With the use of ambulatory monitoring, a circadian blood pressure pattern has been shown to characterize normotensive as well as hypertensive pregnant women. However, the potential differences between healthy and complicated pregnancies in pulse pressure, an independent marker of cardiovascular risk in the general population, have not yet been investigated. We analyzed 2523 blood pressure series sampled for 48 hours once every 4 weeks from the first obstetric visit until delivery in 245 women with uncomplicated pregnancies, 140 with gestational hypertension, and 49 who developed preeclampsia.

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Background And Objective: Recent studies have tried to overcome poor results from isolated blood pressure values in detecting hypertension in pregnancy by relying on ambulatory monitoring. Low sensitivity of the 24-hour mean has led many authors to conclude that ambulatory monitoring is not a valid approach in pregnancy. Against this background, we have evaluated prospectively the sensitivity and specificity in the diagnosis of gestational hypertension of the tolerance-hyperbaric test.

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Several studies have indicated that the use of the 24 h mean blood pressure, mainly using reference thresholds derived from general nonpregnancy practice, does not provide an effective test for an individualized early diagnosis of hypertension in pregnancy, thus concluding that ambulatory blood pressure monitoring is not a valid approach in pregnancy. With the use of ambulatory blood pressure monitoring, epidemiologic studies have reported gender differences in the circadian variability of blood pressure and heart rate. Typically, men exhibit a lower heart rate and higher blood pressure than women, the differences being larger for systolic than for diastolic blood pressure.

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The large-amplitude circadian pattern in blood pressure of healthy subjects of both genders suggests that the constant threshold currently used to diagnose hypertension should be replaced by a time-specified reference limit reflecting the mostly predictable blood pressure variability during the 24 h. Accordingly, we derived circadian time-specified reference standards for blood pressure as a function of gender. We studied 743 normotensive Caucasian volunteers (400 men and 343 women), 45.

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Objectives: This trial investigated and compared the antihypertensive efficacy of telmisartan and valsartan, two angiotensin II receptor blockers, used in monotherapy at their maximum recommended dose in hypertensive patients.

Methods: We studied 70 subjects (32 men and 38 women) aged 47.6 +/- 12.

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Background: The tolerance-hyperbaric test has been shown to provide a valuable approach for the prediction of the outcome of pregnancy. In this test, diagnosis of hypertension is based on the hyperbaric index (area of blood pressure excess above the upper limit of a reference threshold) calculated by comparison with a time-specified tolerance interval for the circadian variability of blood pressure.

Objective: To evaluate prospectively the stability and reproducibility of the tolerance-hyperbaric test.

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The influence of lipophilic factors at the amide fragment of a new series of (+/-)-7a-alkyl-2-[4-(4-arylpiperazin-1-yl)butyl]-1,3-dioxoperhydropyrrolo[1,2-c]imidazoles 2 and of (+/-)-7a-alkyl-2-[(4-arylpiperazin-1-yl)methyl]-1,3-dioxoperhydropyrrolo[1,2-c]imidazoles 3 has been studied. Variations of logP have been carried out by introducing different hydrocarbonated substituents (R(1)) at the position 7a of the bicyclohydantoin, namely the non-pharmacophoric part. All the new compounds exhibit high potency for the 5-HT(1A) receptor; however, affinities for the alpha(1) receptor are high for compounds 2a-l while compounds 3a-f are selective over this adrenergic receptor.

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Studies based on office blood pressure measurements concluded that parity has significant effects on blood pressure during pregnancy. The authors evaluated possible differences in the circadian pattern of blood pressure as a function of parity in normotensive women systematically studied by ambulatory blood pressure monitoring. They analyzed 1400 blood pressure series sampled for 48 consecutive hours every 4 weeks from the first obstetric visit (usually within the first trimester of pregnancy) until delivery in 234 women.

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Objectives: Previous results have indicated that ambulatory monitoring provides a pressor effect on patients using the device for the first time, but not on successive sessions of monitoring. Our objective was to validate and quantify the extent and duration of this pressor effect in hypertensive patients repeatedly evaluated every few months.

Methods: We studied 823 mild-to-moderate hypertensive subjects (347 men), 53.

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Previous studies on ambulatory blood pressure monitoring as a potential screening test for hypertension in pregnancy have not carefully considered sampling requirements. We have examined the impact of duration and frequency of blood pressure sampling in the reproducibility of mean values in pregnancy. We analyzed 2430 blood pressure series sampled every 20 minutes during the day and every 30 minutes at night for 48 hours every 4 weeks from the first obstetric visit until delivery in 235 normotensive and 168 hypertensive pregnant women.

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Background: A seasonal variation with higher values in winter has been previously reported in plasma fibrinogen, a recognized marker of the potential risk of myocardial infarction and stroke. The lack of nocturnal decline in blood pressure has also been associated with an increase in cardiovascular events. Accordingly, we have compared the yearly variation of plasma fibrinogen in dipper and nondipper hypertensive patients.

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This study investigated the administration time-dependent antihypertensive efficacy of valsartan, an angiotensin II receptor blocker. We studied 90 subjects (30 men and 60 women), 49.0+/-14.

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