Objective: To evaluate the relationship between the mechanical properties of the carotid artery wall and baroreflex function after acute reduction of blood pressure with lacidipine in essential hypertension.
Design: After 15 days of placebo washout, the hypertensive patients underwent a single-blind haemodynamic study before and 90 min after administration of 4 mg lacidipine (a dihydropyridine calcium antagonist).
Methods: Brachial intra-arterial blood pressure was recorded in eight mild-to-moderate essential hypertensive patients aged 40-53 years (mean +/- SEM 46.8 +/- 4.7 years). The carotid pulse diameter was recorded simultaneously by an echo-tracking technique. The mechanical properties of the carotid artery wall were evaluated by calculating Peterson's incremental elastic modulus (Ep) both as an averaged value of 10 heart cycles with stable blood pressure and was the dynamic correlation, on a beat-to-beat basis, of Ep and the systolic blood pressure during a 20 mmHg increase in blood pressure following a bolus injection of phenylephrine. The elastic properties of the carotid artery were investigated further by determining the correlation between the systolic pressure and systolic diameter, beat by beat, during a ramped increase of blood pressure after phenylephrine administration. The baroreceptor reflex sensitivity was measured simultaneously by the Oxford method and by correlating Ep and the electrocardiographic R-R' interval on a beat-to-beat basis during phenylephrine injections.
Results: After lacidipine administration Peterson's elastic modulus, measured under resting steady-state conditions, was reduced (18.7 +/- 7.4 versus 16.4 +/- 6 x 10(5) dyne/cm2), whereas the baroreflex sensitivity was unchanged (6.6 +/- 3.3 versus 6.3 +/- 0.2 ms/mmHg) and resetting of the baroreflex had occurred. At the same time, the correlations between the systolic blood pressure and Ep and between the systolic blood pressure and carotid systolic diameter over a 20 mmHg increase in blood pressure were unchanged. Moreover, the correlations between the systolic blood pressure and the R-R' interval and between Ep and R-R' interval during the phenylephrine-induced blood pressure increase did not differ statistically.
Conclusions: The results suggest that the resetting of the baroreflex after the acute reduction in blood pressure caused by lacidipine is dissociated from mechanical changes in the carotid artery wall.
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http://dx.doi.org/10.1097/00004872-199609000-00010 | DOI Listing |
J Sports Sci
January 2025
Physical Activity, Sport and Exercise (PHASE) Research Group, School of Allied Health (Exercise Science), Murdoch University, Perth, Australia.
This study examined internal, external training loads, internal:external ratios, and aerobic adaptations for acute and short-term chronic repeated-sprint training (RST) with blood flow restriction (BFR). Using randomised crossover (Experiment A) and between-subject (Experiment B) designs, 15 and 24 semi-professional Australian footballers completed two and nine RST sessions, respectively. Sessions comprised three sets of 5-7 × 5-second sprints and 25 seconds recovery, with continuous BFR (45% arterial occlusion pressure) or without (Non-BFR).
View Article and Find Full Text PDFHigh Blood Press Cardiovasc Prev
January 2025
Department of Clinical Medicine and Surgery, ESH Excellence Center of Hypertension, "Federico II" University of Naples Medical School, Via S. Pansini, 5, 80131, Naples, Italy.
Introduction: A strong and well-known association exists between salt consumption, potassium intake, and cardiovascular diseases. MINISAL-SIIA results showed high salt and low potassium consumption in Italian hypertensive patients. In addition, a recent Italian survey showed that the degree of knowledge and behaviour about salt was directly interrelated, suggesting a key role of the educational approach.
View Article and Find Full Text PDFJ Endocrinol Invest
January 2025
Department of Medical Area, Section of Metabolic Diseases and Diabetes, University Hospital of Pisa, Via Paradisa, 2, Pisa, 56124, Italy.
Purpose: Women with gestational diabetes (GDM) have increased risk of hypertensive disorders in pregnancy (HDP). However, knowledge remains limited for women with high-risk metabolic profiles, regardless of GDM diagnosis. This study aimed to evaluate the prevalence of HDP among women at high risk for GDM, while simultaneously identifying potential predictive clinical risk factors of HDP.
View Article and Find Full Text PDFAnesthesiology
January 2025
Department of Critical Care, Melbourne Medicine School, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Victoria, Australia.
Background: Multi-compartment computer models of heterogeneity in alveolar ventilation-perfusion ratios (VA/Q scatter) across the lung explain the significant alveolar-arterial (A-a) partial pressure gradients and associated alveolar dead-space fractions (VDA/VA) seen in anesthetized patients for both carbon dioxide and for anesthetic gases of different blood solubilities. However, the accuracy of a simpler two-compartment model of VA/Q scatter to do this has not been tested or compared to calculations from the traditional Riley model with "ideal", unventilated (shunt) and unperfused (deadspace) compartments.
Methods: Measurements of gas partial pressures in inspired and expired gas and arterial and mixed venous blood from 29 patients undergoing inhalational general anesthesia for cardiac surgery was used to compare the accuracy of two simple models of VA/Q scatter and lung gas exchange in predicting measured alveolar and arterial partial pressure differences, and associated alveolar dead-space calculations for the modern anesthetic gases isoflurane, sevoflurane and desflurane.
Antimicrob Agents Chemother
January 2025
Univ. of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 9017-CIIL-Center for Infection and Immunity of Lille, Lille, France.
Self-transmissible IncC plasmids rapidly spread multidrug resistance in many medically important pathogens worldwide. A large plasmid of this type (pIP1202, ~80 Kb) has been isolated in a clinical isolate of , the agent of plague. Here, we report that pIP1202 was highly stable in infected mice and fleas and did not reduce virulence in these animals.
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