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Rollinger B - - 2012
A miniature fast response high temperature pressure probe, with demonstrated use in liquid metals up to 255 °C (528 K), has been developed. Innovative packaging technologies have been applied to integrate a conventional piezoresistive silicon pressure sensor into the probe, without the need of an auxiliary water-cooling system. In situ static ...
Sun Tao - - 2012
Sub-harmonic response from ultrasound contrast agent microbubbles has been demonstrated to be an effective modality for noninvasive pressure measurement. In the present study, the dependence of ultra-harmonic response on the ambient overpressure was investigated by both experimental measurements and simulations. In the measurements, the microbubbles were exposed to Gaussian pulses ...
Bomfim Gisele F GF Department of Pharmacology, University of Sao Paulo, Sao Paulo, SP, Brazil. - - 2012
Activation of TLRs (Toll-like receptors) induces gene expression of proteins involved in the immune system response. TLR4 has been implicated in the development and progression of CVDs (cardio-vascular diseases). Innate and adaptive immunity contribute to hypertension-associated end-organ damage, although the mechanism by which this occurs remains unclear. In the present ...
Kauffenstein Gilles G Biologie Neurovasculaire et Mitochondriale Intégrée, UMR CNRS 6214 INSERM 1083, Université d'Angers, - - 2012
Blood flow autoregulation results from the ability of resistance arteries to reduce or increase their diameters in response to changes in intravascular pressure. The mechanism by which arteries maintain a constant blood flow to organs over a range of pressures relies on this myogenic response, which defines the intrinsic property ...
Wallasch Thomas-Martin - - 2012
PURPOSE.: To provide reference values of cerebrovascular reactivity measured with transcranial Doppler ultrasonography in response to rapid changes in blood pressure during the late straining phase (IIb) of a Valsalva maneuver (VM). METHODS.: Middle cerebral artery blood flow velocity, arterial blood pressure changes, and end-tidal partial carbon dioxide pressure (pCO(2) ...
Turner Stephen T - - 2012
To identify genes influencing blood pressure response to an angiotensin II receptor blocker, single nucleotide polymorphisms identified by genome-wide association analysis of the response to candesartan were validated by opposite direction associations with the response to a thiazide diuretic, hydrochlorothiazide. We sampled 198 white and 193 blacks with primary hypertension ...
Gentili A - - 2012
Caudal block with levobupivacaine or ropivacaine is the most commonly used regional anaesthesia in children. The aim of study was to compare the cardiocirculatory profile induced in two matched groups of young patients, submitted to caudal anaesthesia with levobupivacaine or ropivacaine for an elective subumbilical surgery. Sixty children were enrolled: ...
Sathishkumar Kunju - - 2012
Examine temporal alterations in vascular angiotensin II receptors (AT(1)R and AT(2)R) and determine vascular response to angiotensin II in growth-restricted offspring. Offspring of pregnant rats fed low-protein (6%) and control (20%) diet were compared. Prenatal protein restriction reprogrammed AT(1a)R messenger RNA expression in male rats' mesenteric arteries to cause 1.7- ...
Tate Kevin B - - 2012
Effects of dehydration on reptilian embryonic cardiovascular function are unknown. Here, we present the first morphological and physiological data quantifying the cumulative effects of four acute dehydration events on the embryonic American alligator, Alligator mississipiensis. We hypothesized that dehydration would alter embryonic morphology, reduce blood volume and augment the response ...
Hopps Jamie J - - 2012
Oleamide is an endocannabinoid-like, fatty acid amide with structural similarities to anandamide. The cardiovascular effects of anandamide are enhanced in hypertension and we have now examined how hypertension affects responses to oleamide. Vasorelaxant responses to oleamide were significantly (P<0.001) enhanced in aortic rings from spontaneously hypertensive rats (SHRs), such that ...
Takai Shinji - - 2012
Angiotensin II plays an important role in regulating blood pressure. Moreover, angiotensin II directly promotes organ damage by inducing expression of various genes, such as transforming growth factor (TGF)-β and matrix metalloproteinase (MMP)-9 precursors. Blockade of angiotensin II has been shown to not only lower blood pressure, but also to ...
Shibata Hirotaka - - 2012
The role of aldosterone in the pathogenesis of hypertension and cardiovascular diseases has been clearly shown in congestive heart failure and endocrine hypertension due to primary aldosteronism. In resistant hypertension, defined as a failure of concomitant use of three or more different classes of antihypertensive agents to control blood pressure ...
Prysyazhna Oleksandra - - 2012
Blood pressure regulation is crucial for the maintenance of health, and hypertension is a risk factor for myocardial infarction, heart failure, stroke and renal disease. Nitric oxide (NO) and prostacyclin trigger well-defined vasodilator pathways; however, substantial vasorelaxation in response to agents such as acetylcholine persists when the synthesis of these ...
Brown T C K - - 2012
The physiological application of OHMS LAW explains the basis of hypotensive anesthesia. V = IR translates into: Pressure = Flow × Resistance or Blood pressure = Cardiac Output × Peripheral Resistance. If peripheral resistance is reduced by a vasodilator such as sodium nitroprusside (a short acting, vascular smooth muscle relaxant) or phenoxybenzamine (a long acting α adrenoreceptor antagonist), blood pressure ...
Kairaitis Kristina - - 2012
Increasing lung volume improves upper airway airflow dynamics via passive mechanisms such as reducing upper airway extraluminal tissue pressures (ETP) and increasing longitudinal tension via tracheal displacement. We hypothesized a threshold lung volume for optimal mechanical effects on upper airway airflow dynamics. Seven supine, anesthetized, spontaneously breathing New Zealand White ...
Sekido Noritoshi - - 2012
Hydrodynamic analysis of a pressure flow study is the only reliable method to determine the presence or absence of a bladder outlet obstruction, especially benign prostatic obstruction. To interpret the results of pressure flow study in benign prostatic obstruction, understanding the outlines of the basic theory about evaluation of the ...
Azizi M - - 2012
This review aims to describe the role and the results of catheter-based renal nerve ablation for the treatment of resistant hypertension. Despite the availability of multiple classes of orally active antihypertensive treatments, resistant hypertension remains an important public health issue in 2012 due to its prevalence and association with target-organ ...
Shimizu Ippei - - 2012
Several clinical studies have shown that insulin resistance is prevalent among patients with heart failure, but the underlying mechanisms have not been fully elucidated. Here, we report a mechanism of insulin resistance associated with heart failure that involves upregulation of p53 in adipose tissue. We found that pressure overload markedly ...
Nassar Boulos S - - 2012
PURPOSE: Knowledge of patients' lung compliance and resistance aids clinical management. We investigated whether these values, readily measured during volume assist-control ventilation (VACV), could also be estimated during pressure assist-control ventilation (PACV). METHODS: Data were collected in 12 mechanically ventilated human subjects. During VACV, peak pressure, plateau pressure, end-expiratory pressure, ...
Kish Adrienne - - 2012
In this study, we examined the high-pressure survival of a range of prokaryotes not found in high-pressure environments to determine the effects of adaptations to osmotic and oxidative stresses on piezo-resistance. The pressure survivals of Halobacterium salinarum NRC-1, Deinococcus radiodurans R1, and Chromohalobacter salexigens were compared to that of Escherichia ...
Zeiler Gareth E - - 2012
A 10-month-old, 580 kg, hand-reared white rhinoceros (Ceratotherium simum) calf was presented for emergency exploratory celiotomy. Anaesthesia was safely induced with three successive intravenous (IV) boluses of diazepam (10 mg) and ketamine (100 mg) until the trachea could be intubated. Anaesthesia was adequately maintained with isoflurane-inoxygen (mean end-tidal isoflurane concentration ...
Czosnyka Marek - - 2012
Objective: The programmable Shunt Assistant (capped!) (ProSA) shunt system has recently been introduced into clinical use. The system can be in vivo adjusted magnetically, and this adjustability is supposed to affect CSF drainage only in the vertical body position. Materials and methods: We tested a combination of ProSA with fixed ...
Shujaat Adil - - 2012
In sepsis both under- and overresuscitation are associated with increased morbidity and mortality. Moreover, sepsis can be complicated by myocardial dysfunction, and only half of the critically ill patients exhibit preload responsiveness. It is of paramount importance to accurately, safely, and rapidly determine and optimize preload during resuscitation. Traditional methods ...
Wegner Nicholas C - - 2012
Ram ventilation and gill function in a lamnid shark, the shortfin mako, Isurus oxyrinchus, were studied to assess how gill structure may affect the lamnid-tuna convergence for high-performance swimming. Despite differences in mako and tuna gill morphology, mouth gape and basal swimming speeds, measurements of mako O(2) utilization at the ...
Turner Stephen T - - 2012
To determine whether office, home, ambulatory daytime and nighttime blood pressure (BP) responses to antihypertensive drug therapy measure the same signal and which method provides greatest power to identify genetic predictors of BP response. We analyzed office, home, ambulatory daytime and nighttime BP responses in hypertensive adults randomized to atenolol ...
Hamlin J J - - 2011
We report x-ray diffraction, electrical resistivity, and magnetoresistance measurements on Bi(2)Se(3) under high pressure and low temperature conditions. Pressure induces profound changes in both the room temperature value of the electrical resistivity as well as the temperature dependence of the resistivity. Initially, pressure drives Bi(2)Se(3) toward increasingly insulating behavior and ...
Lai En Yin EY Hypertension, Kidney, and Vascular Research Center, Georgetown University Medical Center, NW, Washington, DC 20007, - - 2012
Myogenic and angiotensin contractions of afferent arterioles generate reactive oxygen species. Resistance vessels express neutrophil oxidase-2 and -4. Angiotensin II activates p47(phox)/neutrophil oxidase-2, whereas it downregulates NOX-4. Therefore, we tested the hypothesis that p47(phox) enhances afferent arteriolar angiotensin contractions. Angiotensin II infusion in p47(phox) +/+ but not -/- mice increased ...
Belfort Michael - - 2011
AUTHORS: Michael Belfort, MBBCH, MD, PhD; Teelkien Van Veen; G. Lance White; ShaleceKofford, RN, MPH; Janalee Allred, RN; InekePostma; Michael Varner, MD OBJECTIVE: To determine if decreased resistance (vasodilatation) in the Maternal Middle Cerebral Artery (MMCA)in the second trimester can predict third trimester development of preeclampsia. STUDY DESIGN: 405 low ...
Tahvanainen Anna M - - 2011
OBJECTIVES:: Pulse wave analysis is widely applied to measure the haemodynamic effects of nitroglycerin and salbutamol as an endothelium-independent and endothelium-dependent vasodilator, respectively. The recordings are usually performed in supine position from 10 to 20 successive heartbeats without simultaneous measurement of vascular resistance and cardiac function. Our objective was to ...
Genovesi Simonetta - - 2011
OBJECTIVE:: The aim of the present study was to evaluate whether insulin resistance [as measured by Homeostasis Model Assessment (HOMA) index] has an effect on prehypertension and hypertension risk in children after acknowledging the role of BMI and waist-to-height ratio. METHODS:: We studied a sample of 377 children 10.5 ± 2.3 years ...
Sen Sayan S International Centre for Circulatory Health, National Heart and Lung Institute, Imperial College London, London, UK. - - 2012
The purpose of this study was to develop an adenosine-independent, pressure-derived index of coronary stenosis severity. Assessment of stenosis severity with fractional flow reserve (FFR) requires that coronary resistance is stable and minimized. This is usually achieved by administration of pharmacological agents such as adenosine. In this 2-part study, we ...
Gamé Xavier - - 2011
Introduction.  Nitric oxide synthases (NOSs) and estrogen receptors are expressed in the female urethra. Aim.  We aimed to assess the impact of sildenafil on micturition behavior, urethral tone according to the hormonal status and to determine the implications of the neuronal isoform of NOS (nNOS). Methods.  Four-week-old C57/BL6 female mice ...
Oto Jun - - 2011
BACKGROUND: Endotracheal tubes (ETT) impose a significant respiratory workload on mechanically ventilated patients. Automatic tube compensation (ATC) should overcome this flow-dependent resistive workload; however, ETT resistance can be increased by tracheal secretions or ETT deformities. Our bench study investigated whether ATC provides effective respiratory workload relief in used ETTs. METHODS: ...
Becken Michael - - 2011
The seismicity pattern along the San Andreas fault near Parkfield and Cholame, California, varies distinctly over a length of only fifty kilometres. Within the brittle crust, the presence of frictionally weak minerals, fault-weakening high fluid pressures and chemical weakening are considered possible causes of an anomalously weak fault northwest of ...
Campana Lisa M - - 2012
The forced oscillation technique (FOT) is a non-invasive technique to monitor airway obstruction in those with asthma. The aim of this study was to design and validate a system to use FOT during sleep, both with and without bi-level positive airway pressure (BPAP), and to separate upper airway resistance from ...
Moraes Milton R - - 2011
Moraes, MR, Bacurau, RFP, Casarini, DE, Jara, ZP, Ronchi, FA, Almeida, SS, Higa, EMS, Pudo, MA, Rosa, TS, Haro, AS, Barros, CC, Pesquero, JB, Würtele, M, and Araujo, RC. Chronic conventional resistance exercise reduces blood pressure in stage 1 hypertensive men. J Strength Cond Res 25(X): 000-000, 2011-To investigate the ...
Kalil Graziela Z GZ Division of Endocrinology, Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, - - 2012
Obesity markedly increases the risk of hypertension and cardiovascular disease, which may be related to activation of the sympathetic nervous system (SNS). Sympathetic overactivity directly and indirectly contributes to blood pressure (BP) elevation in obesity, including stimulation of the renin-angiotensin-aldosterone system (RAAS). The adipocyte-derived peptide leptin suppresses appetite, increases thermogenesis, ...
Doumas Michael - - 2011
Despite the abundance of antihypertensive drugs, resistant hypertension remains a major clinical problem. Recent technological advances render interventional management of resistant hypertension one of the hottest topics in the hypertension field. The aim of this review is to present the pathophysiologic background and the mechanisms mediating blood pressure reduction after ...
Huan Yonghong - - 2011
African Americans have more hypertension and hypertension-related morbidity than whites. Aldosterone, in presence of a high salt intake, contributes to hypertension and tissue injury. Inappropriately elevated aldosterone levels could explain this racial disparity. Our study was conducted to determine if aldosterone is associated with elevated blood pressure (BP) or insulin ...
Kawai Tatsuo - - 2011
Hypertension is an important risk factor for cardiovascular diseases such as chronic kidney disease. It is still not fully understood how blood pressure impacts the kidneys. In this study, we aimed to establish the significance of visit-to-visit variability in blood pressure for renal function. We analyzed 143 consecutive patients undergoing ...
Trovato Guglielmo M - - 2011
Introduction. The renal resistive index (RRI) reflects intrarenal vascular resistance and stiffness, which are associated with chronic kidney disease. The links connecting renal function, intrarenal arterial resistance, and parathyroid hormone (PTH) with hypertension and metabolic factors remain elusive. The aim of this study is to investigate the possible relationship of ...
Kim Jin-Young - - 2011
The vast majority of droplet-based microfluidic devices are made from polydimethylsiloxane (PDMS). Unfortunately PDMS is not suitable for high frequency droplet generation at high operating pressure due to its low shear modulus. In this paper, we report the fabrication and testing of microfluidic devices using thermoset polyester (TPE). The optical ...
Zheng X J - - 2011
A vacuum pressure sensor was fabricated by assembling ZnO nanobelt film on the interdigital electrodes, and the current-voltage characteristics were measured with an Agilent semiconductor parameter tester. Under different pressures of 1.0 × 10(3), 6.7 × 10( - 3), 8.2 × 10( - 4) and 9.5 × 10( - 5) mbar, ...
Pabuccu Turker - - 2011
Objectives: With growing awareness of arterial stiffness (AS) in the past 10 years, it was realized that resistant hypertension (RH) and AS share the same associated conditions such as older age, isolated systolic hypertension (HT), obesity, chronic kidney disease (CKD), and so on. Until now, there is no study investigating ...
Chi Zhenhua - - 2011
A cryogenic loading system for introducing H(2) and D(2) into the diamond anvil cell has been designed and constructed. The integration of pressure loading mechanism, ruby fluorescence spectrometer, and microscope camera allows for in situ tuning and calibrating the pressure. The performance of the system has been demonstrated by successful ...
Mahfoud Felix - - 2011
Resistant hypertension is defined as blood pressure above the target range set by current guidelines despite the concurrent use of three or more antihypertensive drugs of different classes, including a diuretic, at their maximum or highest tolerated doses. This problem affects 5% to 15% of all hypertensive patients and is ...
Cornelissen Véronique A - - 2011
We reviewed the effect of resistance training on blood pressure and other cardiovascular risk factors in adults. Randomized, controlled trials lasting ≥4 weeks investigating the effects of resistance training on blood pressure in healthy adults (age ≥18 years) and published in a peer-reviewed journal up to June 2010 were included. ...
Sacerdoti David D Department of Clinical and Experimental Medicine, University of Padova, Via Giustiniani 2, 35100 Padova, Italy. - - 2011
CYP450-dependent epoxyeicosatrienoic acids (EETs) are potent arterial vasodilators, while 20-hydroxyeicosatatraenoic acid (20-HETE) is a vasoconstrictor. We evaluated their role in the control of portal circulation in normal and cirrhotic (CCl(4) induced) isolated perfused rat liver. Phenylephrine (PE) and endothelin-1 (ET-1) increased portal perfusion pressure, as did arachidonic acid (AA), 20-HETE, ...
Rubini Alessandro - - 2011
Background: Data describing the inhibitory effects of nitric oxide synthase (NOS) on respiratory mechanics are conflicting, and no data are available concerning possible effects on the viscoelasticity of the respiratory system, on the inspiratory work of breathing (WOB) or on respiratory system hysteresis. Objectives: The aim of this study was ...
Guérin Claude - - 2011
The CoughAssist is a mechanical insufflator-exsufflator designed to assist airway secretion clearance in patients with ineffective cough. The device may benefit intubated and tracheotomized patients. We assessed the impact of various artificial airways on peak expiratory flow (PEF) with the CoughAssist. We measured PEF and pressure at the airway opening ...
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