Search results for "Press"
showing 10 items of 15058 documents
Differential effects of potassium channel blockers on neurohypophysial release of oxytocin and vasopressin. Evidence for frequency-dependent interact…
1988
Isolated rat neurohypophyses were fixed by their stalks to a platinum wire electrode and superfused with Krebs-HEPES solution. Vasopressin and oxytocin released into the medium were determined by specific radioimmunoassays. Hormone secretion was increased by electrical stimulation of the pituitary stalk at different frequencies. The effects of several potassium channel blockers, tetraethylammonium (TEA) ions, 4-aminopyridine (4-AP) and 3,4-diaminopyridine (3,4-DAP) were tested. The release of vasopressin and oxytocin evoked by electrical stimulation with 900 pulses at 15 Hz (about 900 and 1,000 μU, respectively) was about 10 times higher than that evoked by 900 pulses at 3 Hz. Both 10 and 3…
The hypothalamic magnocellular neurosecretory system in developing rats
2009
Studies concerning the development of the magnocellular system are scarce and discordant in literature. We carried out an immunohistochemical study on supraotic and paraventricular hypothalamic nuclei using antivasopressin and antioxytocin antibodies in developing rats between the 15th day of intrauterine life and the 6th day of postnatal life. In addition, we performed RT-PCR experiments to establish the stage at which these hormones appear and neurosecretory activity commences. The results showed that supraoptic and paraventricular nuclei appear, respectively, on the 16th and the 18th day of intrauterine life and both immediately synthetize vasopressin neurohormone. By contrast, synthesis…
Vascular effects of progesterone: Role of cellular calcium regulation
2001
Abstract —Vascular actions of progesterone have been reported, independently of estrogen, affecting both blood pressure and other aspects of the cardiovascular system. To study possible mechanisms underlying these effects, we examined the effects of P in vivo in intact rats and in vitro in isolated artery and vascular smooth muscle cell preparations. In anesthetized Sprague-Dawley rats , bolus intravenous injections of P (100 μg/kg) significantly decreased pressor responses to norepinephrine (0.3 μg/kg). In vitro, progesterone (10 −8 to 10 −5 mmol/L) produced a significant, dose-dependent relaxation of isolated helical strips, both of rat tail artery precontracted with KCl (60 mmol/L) or a…
Right ventricular function and iron deficiency in acute heart failure
2021
Abstract Aims Iron deficiency (ID) is a frequent finding in patients with chronic and acute heart failure (AHF) along the full spectrum of left ventricular ejection fraction (LVEF). Iron deficiency has been related to ventricular systolic dysfunction, but its role in right ventricular function has not been evaluated. We sought to evaluate whether ID identifies patients with greater right ventricular dysfunction in the setting of AHF. Methods and results We prospectively included 903 patients admitted with AHF. Right systolic function was evaluated by tricuspid annular plane systolic excursion (TAPSE) and the ratio TAPSE/pulmonary artery systolic pressure (TAPSE/PASP). Iron deficiency was de…
Right Heart Dysfunction and Readmission Risk Across Left Ventricular Ejection Fraction Status in Patients With Acute Heart Failure.
2021
BACKGROUND: Right heart dysfunction (RHD) parameters are increasingly important in heart failure (HF). This study aimed to evaluate the association of advanced RHD with the risk of recurrent admissions across the spectrum of left ventricular ejection fraction (LVEF). METHODS AND RESULTS: We included 3383 consecutive patients discharged for acute HF. Of them, in 1435 patients (42.4%), the pulmonary artery systolic pressure could not be measured accurately, leaving a final sample size of 1948 patients. Advanced RHD was defined as the combination of a ratio of tricuspid annular plane systolic excursion/pulmonary artery systolic pressure of less than 0.36 and significant tricuspid regurgitation…
Defining right ventricular dysfunction by the use of echocardiography in normotensive patients with pulmonary embolism
2020
Although the prognostic value of various echocardiographic parameters of right ventricular dysfunction (RVD) was reported in normotensive patients with acute pulmonary embolism (PE), there is no generally accepted definition of RVD.The aim of the study was to compare echocardiographic parameters for the prediction of an adverse 30‑day outcome and create an optimal definition of RVD. Patients and methods: Echocardiographic parameters including the right ventricular to left ventricular diameter ratio (RV to LV ratio) and tricuspid annular plane systolic excursion (TAPSE) to predict PE‑related mortality, hemodynamic collapse, or rescue thrombolysis within th…
1177 The additive prognostic value of end-systolic pressure-volume relation by CMR in patients with with known or suspected coronary artery disease
2020
Abstract Background The variation between rest and peak stress end-systolic pressure-volume relation is an afterload-independent index of left ventricular contractility. This index is easily obtained during routine stress echocardiography but can be derived also during a stress cardiovascular magnetic resonance (CMR) exam, that is the gold standard for the quantification of biventricular volumes. Purpose The aim of this study was to assess for the first time the prognostic value ofdelta rest-stress ESPVR (DESPVR) by dipyridamole stress-CMR in patients with known or suspected coronary artery disease (CAD). Methods One hundred and sixty-six consecutive patients (37 females, main age 61.96 ± 1…
Dietary cholate increases plasma levels of apolipoprotein B in mice by posttranscriptional mechanisms
2001
To induce atherogenesis in mice, a high fat (HF) diet is supplemented with cholic acid (CA), which increases apoB-containing particles and lower apoA-I-containing particles. HF diet without CA increases levels of both HDL and LDL, suggesting that CA may be responsible for the elevation of LDL and lowering of HDL. The mechanism of dietary CA-induced lowering of apoA-I-containing particles has recently been reported. In this study, we examined the mechanism of CA- and HF-induced elevation of apoB-containing lipoproteins in mice. Mice were fed the following four diets: control chow (C), high fat high cholesterol, (HF), control and 0.5% cholate (CA), and HF + CA. Dietary CA increased the plasma…
Why Do Subjective Vertigo and Dizziness Persist over One Year after a Vestibular Vertigo Syndrome?
2009
The overlap and interlinkage of dizzy symptoms in patients with psychiatric and vestibular vertigo/dizziness disorders is the subject of an ongoing debate. In a one-year follow up in 68 patients with vestibular vertigo syndromes, the persistency of vertigo and dizziness symptoms was examined and correlated with vestibular parameters and results from a psychiatric evaluation. Patients with vestibular migraine showed poorest improvement of vertigo and dizziness symptoms over time. In addition, patients who developed anxiety or depressive disorder after the onset of the vestibular disorder showed poor improvement and high persistency of symptoms.
Vibroacoustic treatment to improve functioning and ability to work: a multidisciplinary approach to chronic pain rehabilitation
2019
Purpose: To study the use of Vibroacoustic treatment and an added self-care intervention for improving the functioning and ability to work of patients with chronic pain and potential comorbid depressive and anxious symptoms.Materials and methods: A mixed methods study with four single cases. Participants received bi-weekly Vibroacoustic practitioner-led treatment sessions for five weeks, followed by a one-month washout period without treatments. Then, participants conducted four self-care vibroacoustic sessions per week for five weeks, followed by another month-long washout period. Participants kept diaries of their experiences during this time. Quantitative scales included the World Health…