Although melatonin lowers blood pressure in spontaneously hypertensive rats (SHR), its effect following antenatal and postpartum supplementation on the subsequent development of hypertension in SHR pups remains unknown. To investigate this, SHR dams were given melatonin in drinking water (10 mg/kg body weight/day) from day 1 of pregnancy until day 21 postpartum. After ...

In this study, 205 nulliparous parturients were enrolled to receive either intermittent (n = 101) or continuous (n = 104) type of epidural analgesia in labour. The primary outcome was rate of caesarean deliveries, whereas secondary outcomes included rate of fundal pressure manoeuvres, duration of labour from application of analgesia, dose of anaesthetic and ...

The Drosophila cuticle carries a rich array of morphological details. Thus, cuticle examination has had a central role in the history of genetics. Studies of the Drosophila cuticle have focused mainly on first-instar larvae and adult cuticular morphology. Although the cuticles of second- and third-instar larvae are strikingly different from ...

To investigate the effect of elevated hydrostatic pressure on the expression and distribution of zonula occludens-1 (ZO-1), and its effect on cytoskeleton and focal adhesion in immortal human trabecular meshwork cells (iHTM) and glaucomatous human trabecular meshwork cells (GTM(3)). iHTM and GTM(3) were exposed to 60 mmHg hydrostatic pressure for 6, ...

BackgroundCaffeine intake has been suggested to be associated with the risk of hypertension. Less is known about the associations of caffeine intake on maternal cardiovascular adaptations during pregnancy. We examined the associations of caffeine intake in different trimesters of pregnancy with repeatedly measured blood pressure and the risks of pregnancy-induced ...

The aim of this study was to determine whether preoperative voiding detrusor pressures were associated with postoperative outcomes after stress incontinence surgery. Opening detrusor pressure, detrusor pressure at maximum flow (p (det) Q(max)), and closing detrusor pressure were assessed from 280 valid preoperative urodynamic studies in subjects without advanced prolapse ...

The authors evaluated the ability of 2 pulse contour cardiac output (CO) techniques to track CO changes during passive leg raising (PLR) to assess fluid loading responsiveness. A prospective study. An intensive care unit in a university hospital. Twenty mechanically ventilated postoperative cardiac surgery patients. Thirty-degree PLR. The authors estimated ...

Our aim was to investigate the effects of acute cold pressor test (CPT) on augmentation index (AI) and wave intensity (WI) indexes from right common carotid artery (RCCA) and right common femoral artery (RCFA) and to test whether the reflection coefficient (RC) from wave intensity analysis can reflect the distal ...

We evaluated 16 pregnant women with gestational age between 20 and 32 weeks in acute severe hypertension which were randomly allocated to receive either hydralazine or labetalol. Blood pressure and Doppler ultrasound parameters from maternal uterine and fetal middle cerebral and umbilical arteries were assessed during acute severe hypertension and ...

Arterial generalized transfer functions (GTFs) are increasingly used to estimate central pressure from peripheral measurements. Analysis of derived central waveforms may be valuable in the assessment of patients with chronic kidney disease. The aim of this study was to assess whether the GTF is affected by renal disease. Ninety-four subjects ...

The cardio-ankle vascular stiffness index (CAVI) is a new parameter that reflects the stiffness of the aorta, femoral artery and tibial artery as a whole. One of its conspicuous features is that CAVI is independent of blood pressure at measuring time, theoretically. But, it has not been experimentally proved yet. ...

There is no doubt as to the existence of a significant relationship between the pulsatile blood pressure component and cardiovascular risk. In hypertensive subjects, cardiovascular event risk reduction is mainly associated with the normalization of systolic blood pressure. Systolic blood pressure and pulse pressure in the ascending aorta exceeds brachial ...

Whether a direct blood pressure-independent reduction in aortic stiffness can occur after several years of antihypertensive treatment has never been unequivocally demonstrated. In this observational study, performed under conditions of routine clinical practice, we included 97 patients (age 63 ± 11 years) with treated essential hypertension who attended the outpatient ...

Dynamic variables are the best predictors of fluid responsiveness in patients under general anesthesia and mechanical ventilation; namely, respiratory variations in pulse pressure and in the plethysmographic waveform. However, these variables have potential limitations. Our aim was to evaluate their intraoperative applicability. We extracted clinical data from all anesthesia procedures ...

Despite the introduction of arterial stiffness measurements in the European recommendation, pulse wave velocity (PWV) and augmentation index (AI) are still not used routinely in clinical practice. It would be of advantage if such measurements were done in the sitting position as is done for blood pressure. The aim of ...

Chronic kidney disease is a proinflammatory state associated with increased arterial stiffness. We hypothesized that chronic kidney disease patients on long-term immunosuppression would have lower arterial stiffness and require treatment with less antihypertensive medication compared with non-immunosuppressed patients. A total of 254 patients (97 on immunosuppression) with chronic kidney disease ...

The data regarding the role of serum uric acid (SUA) along with subclinical inflammation in the context of hypertensive vascular damage are rather scarce and controversial. Towards this end, we assess the links between SUA, high-sensitivity CRP (hs-CRP), adiponectin and carotid to femoral pulse wave velocity (c-f PWV) in 292 ...

Arterial pressure is a cyclic phenomenon characterized by a pressure wave oscillating around the mean blood pressure, from diastolic to systolic blood pressure, defining the pulse pressure. Aortic input impedance is a measure of the opposition of the circulation to an oscillatory flow input (stroke volume generated by heart work). ...

Pulse wave velocity (PWV) and pulse pressure amplification (PPA) are independent predictors of cardiovascular risk, mainly in the elderly. The aim of the current research was to determine the influence of PPA and PWV, both manifestations of arterial stiffness, on heart disease in the elderly. The study population consisted of ...

The aim of this study was to describe resting pulse rate and associated factors among adolescents. This was a cross-sectional analysis nested in a prospective cohort study, including 4,452 adolescents born in Pelotas, Rio Grande do Sul State, Brazil in 1993, representing 87.5% of the original cohort. Pulse rate was ...

The importance of measuring aortic pulse wave velocity (PWVao), aortic augmentation index (Aix) and central systolic blood pressure (SBPao) has been shown under different clinical conditions; however, information on these parameters is hard to obtain. The aim of this study was to evaluate the accuracy of a new, easily applicable ...

It is known fact that pre-oxygenation with positive end-expiratory pressure (PEEP) improves the Partial pressure of oxygen (PO (2)). In this regard not many studies have been done in pregnant women to know its effect on foetus. In this randomised double blind controlled study, we analysed effect of pre-oxygenation with ...

Arterial stiffness, assessed by carotid-femoral pulse wave velocity (PWV) or indirectly by pulse pressure (PP) or ambulatory arterial stiffness index (AASI), is an independent predictor of cardiovascular disease in adults. However, in children limited evidence is available. This study investigated the usefulness of AASI and PP as indices of arterial ...

Aortic stiffness, peripheral wave reflection, and aorta-to-peripheral pulse pressure amplification all predict cardiovascular risk. However, the pathophysiological mechanism behind it is unknown. Tonometric pressure waveforms were recorded on the radial, carotid, and femoral arteries in 138 hypertensive patients (age: 56±13 years) to estimate aorta-to-peripheral amplifications, aortic augmentation index, and aortic ...

Systolic blood pressure and pulse pressure are substantially higher in older adults. The relative contributions of increased forward versus reflected pressure wave amplitude or earlier arrival of the reflected wave to elevated pulse pressure remain controversial. We measured proximal aortic pressure and flow, forward pressure wave amplitude, global wave reflection, ...

Although contour analysis of pulse waves has been proposed as a non-invasive means in assessing arterial stiffness in atherosclerosis, accurate determination of the conventional parameters is usually precluded by distorted waveforms in the aged and atherosclerotic objects. We aimed at testing reliable indices in these patient populations. Digital volume pulse ...

Migraine has been associated with an increased risk for ischemic stroke and other cardiovascular (CV) events, including angina, myocardial infarction, and CV death, but the mechanisms that link migraine to CV disease remain uncertain. We hypothesized that aortic pulse wave velocity (PWV), a direct measure of aortic stiffness and an ...

We developed a technique to calculate forward and backward arterial waves from proximal and distal pressure waveforms. First, the relationship between the waveforms is represented with an arterial tube model. Then, the model parameters are estimated via least-squares fitting. Finally, the forward and backward waves are calculated using the parameter ...

This study examined whether elevated intravascular pressure stimulates asynchronous Ca(2+) waves in cerebral arterial smooth muscle cells and if their generation contributes to myogenic tone development. The endothelium was removed from rat cerebral arteries, which were then mounted in an arteriograph, pressurized (20-100 mmHg) and examined under a variety of ...

Although central pulse pressure (PPc) is strongly related to central mean arterial pressure (MAPc), PPc predicts cardiovascular outcomes beyond MAPc. Whether modifiable risk factors for hypertension contribute to PPc and its determinants, independent of MAPc, is uncertain. In 635 randomly recruited participants, we assessed the independent relationship between 24-hour urinary ...

This study was aimed at comparing the arterial blood pressures in steady state adult sickle cell patients with those of age- and sex-matched healthy controls. A descriptive cross-sectional study of 62 sickle cell anemia patients and 62 age- and sex-matched healthy controls was carried out in the adult outpatient sickle ...

The main objectives of this study were to examine the acute effect of a single dose of smokeless tobacco (ST) on central aortic blood pressure and wave reflection characteristics. Fifteen apparently healthy male subjects (aged 30.6 ± 6.2 y) were given a 2.5 g oral dose of ST after baseline ...

A mechanical model of pressure propulsion of a sphere in a viscous compressible fluid is studied on the basis of the linearized Navier-Stokes equations. It is assumed that chemical reactions in the neighborhood of the sphere cause pressure waves which push the sphere. A simple expression is derived for the ...

Ageing exerts differential effects on arterial stiffness and wave reflections. However, the impact of cardiovascular risk factors on arterial stiffness and wave reflections and, particularly, how such effects are influenced by ageing has not been assessed within a single large population, covering a sufficiently wide age range. Therefore, we determined ...

OBJECTIVE: The purpose of this article is to establish the range of normal splenic stiffness in healthy volunteers using MR elastography (MRE) and to investigate any correlation with physiologic parameters and driver position. SUBJECTS AND METHODS: Sixteen volunteers (mean [+/- SD] age, 37 +/- 9 years) with no history of ...

BACKGROUND: Increased arterial stiffness is linked to hypertension in adults after surgical repair for coarctation of the aorta. We evaluated the influence of surgical approaches, namely, subclavian flap repair (SFR) and end-to-end anastomosis (EEA), on arterial stiffness, blood pressure, cardiac output, and cardiac baroreceptor function in a cohort of young ...

We present a case of ischemic changes after application of an adult pulse oximeter probe in an infant for a short period of only 10 min. To understand the physiology behind this mishap, we studied pressure exerted by the adult pulse oximeter probe on simulated fingers (fluid-filled pouches), which were ...

Arterial aging can be attributed to two different pathophysiological changes--increase in arterial stiffness and disturbed wave reflections. The capacity of the aorta to absorb the force exerted by the left ventricular ejection and dampen pulsatile flow becomes diminished with advancing age, owing to the progressive hardening of the arterial wall. ...

Aortic stiffness may be associated with an increased incidence of cardiovascular events and has been reported to be related to arterial wall motion velocities as measured by tissue Doppler imaging. To investigate the potential clinical application of tissue Doppler imaging (TDI) for assessment of aortic function parameters in healthy and ...

Oral L-citrulline is efficiently converted to L-arginine, the precursor for endothelial nitric oxide (NO) synthesis. Oral L-arginine supplementation reduces brachial blood pressure (BP). We evaluated the effects of watermelon supplementation on aortic BP and arterial function in individuals with prehypertension. Heart rate (HR), brachial systolic BP (bSBP), brachial pulse pressure ...

BACKGROUND: Respiratory-induced arterial and plethysmographic (pulse oximetry) waveform changes were shown to be good predictors of cardiac output response to increased preload. The aim of this study was to evaluate the reliability of arterial and plethysmographic waveform variables in patients with mild hypovolemia. METHODS: Patients undergoing autologous hemodilution were studied. ...

We assessed changes in pulse pressure and heart rate during a squatting test, as indirect markers of arterial stiffness and cardiovascular autonomic neuropathy, respectively, according to age and sex in patients with Type 1 diabetes mellitus. We evaluated 160 diabetic patients, divided into four groups of 20 men and 20 ...

Arterial stiffness is an independent cardiovascular risk factor, along with aging, hypertension, and cardiovascular disease. The augmentation index (AIx) and pulse wave velocity (PWV) are early markers of atherosclerotic vascular changes. Arteriography was used to determine systolic and diastolic blood pressure, pulse pressure (PP), AIx, and PWV in 82 male ...

The purpose of this pilot study was to determine whether Therapeutic Touch (TT) can be effectively used in the operative setting and whether it could produce positive outcomes in the period from cerebral angiography to discharge. The specific outcomes to be assessed were blood pressure, pulse, and respirations. TT is ...

During the last half million years, pulses of gigantism in the anagenetic lineage of land snails of the subgenus Poecilozonites on Bermuda were correlated with glacial periods when lower sea level resulted in an island nearly an order of magnitude larger than at present. During those periods, the island was ...

We studied the effect of pressure variation on intrapulse Raman scattering for a single-cycle and few-cycle pulses in a gas cell of a given length filled with gaseous deuterium, in the framework of a new model equation that goes beyond the slowly varying envelope approximation. We show that, for a ...

Arterial stiffness is an important determinant of cardiovascular risk. The precise risk factors for arterial stiffening remain unclear. We aimed to identify potential risk factors using prospective exposure data from the Caerphilly Prospective Study. Aortic pulse wave velocity and augmentation index were measured in 825 men and related to current ...

A 23 year-old woman with chronic hypertension, focal segmental glomerular sclerosis with chronic renal insufficiency, and superimposed severe preeclampsia, required cesarean delivery. The patient's course was also complicated by severe hyperkalemia and hypermagnesemia. "PulseCO" pulse contour analysis of a directly measured radial artery pressure tracing, without lithium calibration, enabled her ...

BACKGROUND: Some aortic aneurysm (AA) or aortic dissection (AD) patients can be observed to detect disease progression if optimal blood pressure is achieved. However, in another group of patients, disease progression occurs despite well-controlled blood pressure. The aim of this study was to determine the prognostic value of central aortic ...

OBJECTIVES: We sought to investigate the plausible interrelationship of exaggerated blood pressure response during exercise (EBPR) with ambulatory arterial stiffness index (AASI) in never-treated patients with uncomplicated essential hypertension. METHODS: Ninety-nine never-treated hypertensive patients (aged 50.7 years, 61 male) underwent 24 h ambulatory blood pressure (BP) recording, complete echocardiographic study ...