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Sample records for arterial pressure increases

  1. Acute lead exposure increases arterial pressure: role of the renin-angiotensin system.

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    Maylla Ronacher Simões

    Full Text Available BACKGROUND: Chronic lead exposure causes hypertension and cardiovascular disease. Our purpose was to evaluate the effects of acute exposure to lead on arterial pressure and elucidate the early mechanisms involved in the development of lead-induced hypertension. METHODOLOGY/PRINCIPAL FINDINGS: Wistar rats were treated with lead acetate (i.v. bolus dose of 320 µg/Kg, and systolic arterial pressure, diastolic arterial pressure and heart rate were measured during 120 min. An increase in arterial pressure was found, and potential roles of the renin-angiotensin system, Na(+,K(+-ATPase and the autonomic reflexes in this change in the increase of arterial pressure found were evaluated. In anesthetized rats, lead exposure: 1 produced blood lead levels of 37±1.7 µg/dL, which is below the reference blood concentration (60 µg/dL; 2 increased systolic arterial pressure (Ct: 109±3 mmHg vs Pb: 120±4 mmHg; 3 increased ACE activity (27% compared to Ct and Na(+,K(+-ATPase activity (125% compared to Ct; and 4 did not change the protein expression of the α1-subunit of Na(+,K(+-ATPase, AT(1 and AT(2. Pre-treatment with an AT(1 receptor blocker (losartan, 10 mg/Kg or an ACE inhibitor (enalapril, 5 mg/Kg blocked the lead-induced increase of arterial pressure. However, a ganglionic blockade (hexamethonium, 20 mg/Kg did not prevent lead's hypertensive effect. CONCLUSION: Acute exposure to lead below the reference blood concentration increases systolic arterial pressure by increasing angiotensin II levels due to ACE activation. These findings offer further evidence that acute exposure to lead can trigger early mechanisms of hypertension development and might be an environmental risk factor for cardiovascular disease.

  2. Increasing arterial blood pressure with norepinephrine does not improve microcirculatory blood flow: a prospective study

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    A. Dubin; M.O. Pozo; C.A. Casabella; F.,Jr Pálizas; G. Murias; M.C. Moseinco; V.S. Kanoore Edul; F. Pálizas; E. Estenssoro; C. Ince

    2009-01-01

    Introduction Our goal was to assess the effects of titration of a norepinephrine infusion to increasing levels of mean arterial pressure (MAP) on sublingual microcirculation. Methods Twenty septic shock patients were prospectively studied in two teaching intensive care units. The patients were mecha

  3. Vitamin D induces increased systolic arterial pressure via vascular reactivity and mechanical properties.

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    Priscila Portugal Dos Santos

    Full Text Available The aim of this study was to evaluate whether supplementation of high doses of cholecalciferol for two months in normotensive rats results in increased systolic arterial pressure and which are the mechanisms involved. Specifically, this study assesses the potential effect on cardiac output as well as the changes in aortic structure and functional properties.Male Wistar rats were divided into three groups: 1 Control group (C, n = 20, with no supplementation of vitamin D, 2 VD3 (n = 19, supplemented with 3,000 IU vitamin D/kg of chow; 3 VD10 (n = 21, supplemented with 10,000 IU vitamin D/kg of chow. After two months, echocardiographic analyses, measurements of systolic arterial pressure (SAP, vascular reactivity, reactive oxygen species (ROS generation, mechanical properties, histological analysis and metalloproteinase-2 and -9 activity were performed.SAP was higher in VD3 and VD10 than in C rats (p = 0.001. Echocardiographic variables were not different among groups. Responses to phenylephrine in endothelium-denuded aortas was higher in VD3 compared to the C group (p = 0.041. Vascular relaxation induced by acetylcholine (p = 0.023 and sodium nitroprusside (p = 0.005 was impaired in both supplemented groups compared to the C group and apocynin treatment reversed impaired vasodilation. Collagen volume fraction (<0.001 and MMP-2 activity (p = 0.025 was higher in VD10 group compared to the VD3 group. Elastin volume fraction was lower in VD10 than in C and yield point was lower in VD3 than in C.Our findings support the view that vitamin D supplementation increases arterial pressure in normotensive rats and this is associated with structural and functional vascular changes, modulated by NADPH oxidase, nitric oxide, and extracellular matrix components.

  4. Middle cerebral artery occlusion in presence of low perfusion pressure increases infarct size in rats

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    Sillesen, H; Nedergaard, Majken; Schroeder, T;

    1988-01-01

    A model was set up in order to evaluate the importance of hemispheric perfusion pressure when the middle cerebral artery (MCA) is occluded in anaesthetized rats. In 6 animals the internal carotid artery (ICA) was occluded prior to ipsilateral MCA occlusion; in 17 animals the MCA only was occluded...

  5. Increased wall tension in response to vasoconstrictors in isolated mesenteric arterial rings from patients with high blood pressure.

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    Tahvanainen, Anna; Taurio, Jyrki; Mäki-Jouppi, Jenni; Kööbi, Peeter; Mustonen, Jukka; Kähönen, Mika; Sand, Juhani; Nordback, Isto; Pörsti, Ilkka

    2006-12-01

    Essential hypertension is associated with several alterations in arterial function. A wealth of information from animal models is available concerning hypertensive changes in the mesenteric circulation, while only few studies have examined human mesenteric arterial function. The tone of isolated mesenteric arterial segments (outer diameter 0.7-0.9 mm) was examined from individuals with high (n=17) or normal (n=22) blood pressure, grouped using the current definition of elevated blood pressure (140/90 mmHg). Since the majority of them were operated because of malignancies, we evaluated whether functional vascular properties provided information about patient prognosis. Wall tension development (mN/mm) in response to vasoconstrictors (noradrenaline, 5-hydroxy tryptamine, potassium chloride) was higher in mesenteric arterial rings from patients with high than normal blood pressure. There was no difference in vasoconstrictor sensitivity, or endothelium-dependent and endothelium-independent vasorelaxation. Arterial segment weight was higher in hypertensive subjects, suggesting vascular wall hypertrophy. The 10-year follow-up showed no differences in the control of arterial tone between the surviving (n=14) or deceased (n=25) patients. In conclusion, isolated mesenteric arterial segments from hypertensive patients showed increased wall tension in response to vasoconstrictors. Since the mesenteric circulation is an important regulator of peripheral arterial resistance, possible functional alterations in this vascular bed should be further investigated in hypertensive patients.

  6. Increased pressure-induced tone in rat parenchymal arterioles vs. middle cerebral arteries: role of ion channels and calcium sensitivity.

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    Cipolla, Marilyn J; Sweet, Julie; Chan, Siu-Lung; Tavares, Matthew J; Gokina, Natalia; Brayden, Joseph E

    2014-07-01

    Brain parenchymal arterioles (PAs) are high-resistance vessels that branch off pial arteries and perfuse the brain parenchyma. PAs are the target of cerebral small vessel disease and have been shown to have greater pressure-induced tone at lower pressures than pial arteries. We investigated mechanisms by which brain PAs have increased myogenic tone compared with middle cerebral arteries (MCAs), focusing on differences in vascular smooth muscle (VSM) calcium and ion channel function. The amount of myogenic tone and VSM calcium was measured using Fura 2 in isolated and pressurized PAs and MCAs. Increases in intraluminal pressure caused larger increases in tone and cytosolic calcium in PAs compared with MCAs. At 50 mmHg, myogenic tone was 37 ± 5% for PAs vs. 6.5 ± 4% for MCAs (P channel (VDCC) inhibitor nifedipine than MCAs (EC50 for PAs was 3.5 ± 0.4 vs. 82.1 ± 2.1 nmol/l for MCAs;P channel inhibitor iberiotoxin, whereas MCAs constricted ∼15%. Thus increased myogenic tone in PAs appears related to differences in ion channel activity that promotes VSM membrane depolarization but not to a direct sensitization of the contractile apparatus to calcium.

  7. Estimated aortic blood pressure based on radial artery tonometry underestimates directly measured aortic blood pressure in patients with advancing chronic kidney disease staging and increasing arterial stiffness

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    Carlsen, Rasmus K; Peters, Christian D; Khatir, Dinah S;

    2016-01-01

    we compared invasive aortic systolic BP (SBP) with estimated central SBP obtained by radial artery tonometry and examined the influence of renal function and arterial stiffness on this relationship. We evaluated 83 patients with stage 3 to 5 CKD (mean estimated glomerular filtration rate [eGFR] 30 ml......% confidence interval -14.9 to -11.4) mm Hg. Arterial stiffness was evaluated by carotid-femoral pulse wave velocity (cf-PWV) and was significantly increased in CKD patients compared with (versus) control patients (mean 10.7 vs. 9.3 m/s). The difference in BP significantly increased 1.0 mm Hg for every 10 ml....../min decrease in eGFR and by 1.6 mm Hg per 1 m/s increase in cfPWV. Using multivariate regression analysis including both eGFR and cfPWV, the difference between estimated central and invasive aortic SBP was significantly increased by 0.7 mm Hg. For the entire cohort brachial SBP significantly better reflected...

  8. Children and Adolescent Obesity Associates with Pressure-Dependent and Age-Related Increase in Carotid and Femoral Arteries' Stiffness and Not in Brachial Artery, Indicative of Nonintrinsic Arterial Wall Alteration

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    García-Espinosa, Victoria; Curcio, Santiago; Castro, Juan Manuel; Arana, Maite; Giachetto, Gustavo; Chiesa, Pedro; Zócalo, Yanina

    2016-01-01

    Aim. To analyze if childhood obesity associates with changes in elastic, transitional, and/or muscular arteries' stiffness. Methods. 221 subjects (4–15 years, 92 females) were assigned to normal weight (NW, n = 137) or obesity (OB, n = 84) groups, considering their body mass index z-score. Age groups were defined: 4–8; 8–12; 12–15 years old. Carotid, femoral, and brachial artery local stiffness was determined through systodiastolic pressure-diameter and stress-strain relationships. To this end, arterial diameter and peripheral and aortic blood pressure (BP) levels and waveforms were recorded. Carotid-femoral, femoropedal, and carotid-radial pulse wave velocities were determined to evaluate aortic, lower-limb, and upper-limb regional arterial stiffness, respectively. Correlation analysis between stiffness parameters and BP was done. Results. Compared to NW, OB subjects showed higher peripheral and central BP and carotid and femoral stiffness, reaching statistical significance in subjects aged 12 and older. Arterial stiffness differences disappeared when levels were normalized for BP. There were no differences in intrinsic arterial wall stiffness (elastic modulus), BP stiffness relationships, and regional stiffness parameters. Conclusion. OB associates with BP-dependent and age-related increase in carotid and femoral (but not brachial) stiffness. Stiffness changes would not be explained by intrinsic arterial wall alterations but could be associated with the higher BP levels observed in obese children. PMID:27066273

  9. Preliminary study of abnormal increase of postexercise systolic blood pressure in the diagnosis of coronary artery disease

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    于宗良; 杨向军; 王国强; 高美雯; 李勋; 惠杰; 蒋廷波; 宋建平; 刘志华; 蒋文平

    2003-01-01

    Objectives This study sought to evaluate the diagnostic value of abnormal increase of postexercise systolic blood pressure (SBP) for detecting coronary artery disease (CAD) in patients with or without hypertension. Methods Treadmill exercise testing (TET) was conducted in 88 patients (40 CAD patients, 48 control subjects)with or without hypertension, each of whom underwent selective coronary angiography (CAG). The abnormal increase of postexercise SBP was defined as 10mmHg higher than earlier periods during the recovery phase (6 minutes)of exercise testing. Results The abnormal increase of postexercise SBP had higher sensitivity, specificity,and accuracy for detecting CAD than those of ST - segment depression in patients with or without hypertension. Its accuracy increased with the severity of CAD while decreased in patients with hypertension, and the increase value of SBP had a positive correlation with the extent of coronary artery lesion. The combination of ST - segment depression and abnormal increase of postexercise SBP diagnosed CAD most accurately in patients with hypertension. Conclusions Abnormal increase of postexercise SBP may be a useful index for diagnosing CAD.

  10. [Measurement of arterial pressure].

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    Rorive, G

    1998-03-01

    The casual determination of blood pressure remains the basis of the diagnosis of arterial hypertension and the criteria for usefulness of drug therapy. The reference values usually in use concern determinations by the doctor in very well defined conditions, rest, size of the bladder, etc.... The poor reproductibility of the determinations made by the doctor in casual conditions has produced a large interest for new approaches: autodetermination by the patient at home, and ambulatory blood pressure determinations using automatic devices. These new approaches have their own reference values, specific indications and limitations.

  11. Increasing mean arterial pressure in cardiogenic shock secondary to myocardial infarction: effects on hemodynamics and tissue oxygenation.

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    Perez, Pierre; Kimmoun, Antoine; Blime, Vincent; Levy, Bruno

    2014-04-01

    There are very few data regarding the effects of norepinephrine uptitration on global and regional hemodynamics in cardiogenic shock. We studied 25 patients with shock secondary to myocardial infarction successfully treated with percutaneous coronary intervention. Before the inclusion, 16 of 25 patients presented a cardiac arrest in the presence of medical staff. Norepinephrine was titrated to increase mean arterial pressure (MAP) from 65 to 85 mmHg during 1 h. Swan-Ganz variables, arterial and mixed venous blood gases, lactate, and thenar near-infrared spectroscopy variables (muscle tissue oxygen saturation [StO2] and its changes during a vascular occlusion test) were measured before, 1 h after norepinephrine uptitration, and 1 h after norepinephrine downtitration. To obtain a MAP at 85 mmHg, norepinephrine was increased from 0.6 (0.28-1.2) to 1.53 µg · kg · min (0.76-2.6 µg · kg · min) (P cardiogenic shock complicated by postreperfusion disease is associated with better cardiac performance and improved microcirculatory variables.

  12. Exhaled and arterial levels of endothelin-1 are increased and correlate with pulmonary systolic pressure in COPD with pulmonary hypertension

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    Dragonieri Silvano

    2008-09-01

    Full Text Available Abstract Background Endothelin-1 (ET-1 and Nitric Oxide (NO are crucial mediators for establishing pulmonary artery hypertension (PAH. We tested the hypothesis that their imbalance might also occur in COPD patients with PAH. Methods The aims of the study were to measure exhaled breath condensate (EBC and circulating levels of ET-1, as well as exhaled NO (FENO levels by, respectively, a specific enzyme immunoassay kit, and by chemiluminescence analysis in 3 groups of subjects: COPD with PAH (12, COPD only (36, and healthy individuals (15. In order to evaluate pulmonary-artery systolic pressure (PaPs, all COPD patients underwent Echo-Doppler assessment. Results Significantly increased exhaled and circulating levels of ET-1 were found in COPD with PAH compared to both COPD (p 1%, (r = -0.59, p = 0.043, and PaPs negatively correlated to PaO2 (r = -0.618; p = 0.032. Significantly reduced levels of FENO were found in COPD associated with PAH, compared to COPD only (22.92 ± 11.38 vs.35.07 ± 17.53 ppb; p = 0.03. Thus, we observed an imbalanced output in the breath between ET-1 and NO, as expression of pulmonary endothelium and epithelium impairment, in COPD with PAH compared to COPD only. Whether this imbalance is an early cause or result of PAH due to COPD is still unknown and deserves further investigations.

  13. Estimated aortic blood pressure based on radial artery tonometry underestimates directly measured aortic blood pressure in patients with advancing chronic kidney disease staging and increasing arterial stiffness.

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    Carlsen, Rasmus K; Peters, Christian D; Khatir, Dinah S; Laugesen, Esben; Bøtker, Hans Erik; Winther, Simon; Buus, Niels H

    2016-10-01

    Central blood pressure (BP) can be assessed noninvasively based on radial tonometry and may potentially be a better predictor of clinical outcome than brachial BP. However, the validity of noninvasively obtained estimates has never been examined in patients with chronic kidney disease (CKD). Here we compared invasive aortic systolic BP (SBP) with estimated central SBP obtained by radial artery tonometry and examined the influence of renal function and arterial stiffness on this relationship. We evaluated 83 patients with stage 3 to 5 CKD (mean estimated glomerular filtration rate [eGFR] 30 ml/min/1.73 m(2)) and 41 controls without renal disease undergoing scheduled coronary angiography. BP in the ascending aorta was measured through the angiography catheter and simultaneously estimated using radial tonometry. The mean difference between estimated central and aortic SBP was -13.2 (95% confidence interval -14.9 to -11.4) mm Hg. Arterial stiffness was evaluated by carotid-femoral pulse wave velocity (cf-PWV) and was significantly increased in CKD patients compared with (versus) control patients (mean 10.7 vs. 9.3 m/s). The difference in BP significantly increased 1.0 mm Hg for every 10 ml/min decrease in eGFR and by 1.6 mm Hg per 1 m/s increase in cfPWV. Using multivariate regression analysis including both eGFR and cfPWV, the difference between estimated central and invasive aortic SBP was significantly increased by 0.7 mm Hg. For the entire cohort brachial SBP significantly better reflected invasive SBP than estimated SBP. Thus, tonometry-based estimates of central BP progressively underestimate invasive central SBP with decreasing renal function and increasing arterial stiffness in CKD patients.

  14. Abnormal shortened diastolic time length at increasing heart rates in patients with abnormal exercise-induced increase in pulmonary artery pressure

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    Bombardini Tonino

    2011-11-01

    Full Text Available Abstract Background The degree of pulmonary hypertension is not independently related to the severity of left ventricular systolic dysfunction but is frequently associated with diastolic filling abnormalities. The aim of this study was to assess diastolic times at increasing heart rates in normal and in patients with and without abnormal exercise-induced increase in pulmonary artery pressure (PASP. Methods. We enrolled 109 patients (78 males, age 62 ± 13 years referred for exercise stress echocardiography and 16 controls. The PASP was derived from the tricuspid Doppler tracing. A cut-off value of PASP ≥ 50 mmHg at peak stress was considered as indicative of abnormal increase in PASP. Diastolic times and the diastolic/systolic time ratio were recorded by a precordial cutaneous force sensor based on a linear accelerometer. Results At baseline, PASP was 30 ± 5 mmHg in patients and 25 ± 4 in controls. At peak stress the PASP was normal in 95 patients (Group 1; 14 patients (Group 2 showed an abnormal increase in PASP (from 35 ± 4 to 62 ± 12 mmHg; P Conclusion The first and second heart sound vibrations non-invasively monitored by a force sensor are useful for continuously assessing diastolic time during exercise. Exercise-induced abnormal PASP was associated with reduced diastolic time at heart rates beyond 100 beats per minute.

  15. Heterozygous disruption of activin receptor-like kinase 1 is associated with increased arterial pressure in mice

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    María González-Núñez

    2015-11-01

    Full Text Available The activin receptor-like kinase 1 (ALK-1 is a type I cell-surface receptor for the transforming growth factor-β (TGF-β family of proteins. Hypertension is related to TGF-β1, because increased TGF-β1 expression is correlated with an elevation in arterial pressure (AP and TGF-β expression is upregulated by the renin-angiotensin-aldosterone system. The purpose of this study was to assess the role of ALK-1 in regulation of AP using Alk1 haploinsufficient mice (Alk1+/−. We observed that systolic and diastolic AP were significantly higher in Alk1+/− than in Alk1+/+ mice, and all functional and structural cardiac parameters (echocardiography and electrocardiography were similar in both groups. Alk1+/− mice showed alterations in the circadian rhythm of AP, with higher AP than Alk1+/+ mice during most of the light period. Higher AP in Alk1+/− mice is not a result of a reduction in the NO-dependent vasodilator response or of overactivation of the peripheral renin-angiotensin system. However, intracerebroventricular administration of losartan had a hypotensive effect in Alk1+/− and not in Alk1+/+ mice. Alk1+/− mice showed a greater hypotensive response to the β-adrenergic antagonist atenolol and higher concentrations of epinephrine and norepinephrine in plasma than Alk1+/+ mice. The number of brain cholinergic neurons in the anterior basal forebrain was reduced in Alk1+/− mice. Thus, we concluded that the ALK-1 receptor is involved in the control of AP, and the high AP of Alk1+/− mice is explained mainly by the sympathetic overactivation shown by these animals, which is probably related to the decreased number of cholinergic neurons.

  16. Orexins depolarize rostral ventrolateral medulla neurons and increase arterial pressure and heart rate in rats mainly via orexin 2 receptors.

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    Huang, Shang-Cheng; Dai, Yu-Wen E; Lee, Yen-Hsien; Chiou, Lih-Chu; Hwang, Ling-Ling

    2010-08-01

    An injection of orexin A or B into the cisterna magna or the rostral ventrolateral medulla (RVLM), where bulbospinal vasomotor neurons are located, elevated arterial pressure (AP) and heart rate (HR). We examined how orexins affected RVLM neurons to regulate cardiovascular functions by using in vitro recordings of neuronal activity of the RVLM and in vivo measurement of cardiovascular functions in rats. Orexin A and B concentration-dependently depolarized RVLM neurons. At 100 nM, both peptides excited 42% of RVLM neurons. Tetrodotoxin failed to block orexin-induced depolarization. In the presence of N-(2-methyl-6-benzoxazolyl)-N'-1, 5-naphthyridin-4-yl urea (SB-334867), an orexin 1 receptor (OX(1)R) antagonist, orexin A depolarized 42% of RVLM neurons with a smaller, but not significantly different, amplitude (4.9 +/- 0.8 versus 7.2 +/- 1.1 mV). In the presence of (2S)-1- (3,4-dihydro-6,7-dimethoxy-2(1H)-isoquinolinyl)-3,3-dimethyl-2-[(4-pyridinylmethyl)amino]-1-butanone hydrochloride (TCS OX2 29), an orexin 2 receptor (OX(2)R) antagonist, orexin A depolarized 25% of RVLM neurons with a significantly smaller amplitude (1.7 +/- 0.5 mV). Coapplication of both antagonists completely eliminated orexin A-induced depolarization. An OX(2)R agonist, [Ala(11),D-Leu(15)]-orexin B, concentration-dependently depolarized RVLM neurons. Regarding neuronal phenotypes, orexins depolarized 88% of adrenergic, 43% of nonadrenergic, and 36 to 41% of rhythmically firing RVLM neurons. Intracisternal TCS OX2 29 (3 and 10 nmol) suppressed intracisternal orexin A-induced increases of AP and HR, whereas intracisternal SB-334867 (3 and 10 nmol) had no effect on the orexin A-induced increase of HR but suppressed the orexin A-induced pressor response at 10 nmol. We concluded that orexins directly excite RVLM neurons, which include bulbospinal vasomotor neurons, and regulate cardiovascular function mainly via the OX(2)R, with a smaller contribution from the OX(1)R.

  17. Children and Adolescent Obesity Associates with Pressure-Dependent and Age-Related Increase in Carotid and Femoral Arteries’ Stiffness and Not in Brachial Artery, Indicative of Nonintrinsic Arterial Wall Alteration

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    Victoria García-Espinosa

    2016-01-01

    Full Text Available Aim. To analyze if childhood obesity associates with changes in elastic, transitional, and/or muscular arteries’ stiffness. Methods. 221 subjects (4–15 years, 92 females were assigned to normal weight (NW, n=137 or obesity (OB, n=84 groups, considering their body mass index z-score. Age groups were defined: 4–8; 8–12; 12–15 years old. Carotid, femoral, and brachial artery local stiffness was determined through systodiastolic pressure-diameter and stress-strain relationships. To this end, arterial diameter and peripheral and aortic blood pressure (BP levels and waveforms were recorded. Carotid-femoral, femoropedal, and carotid-radial pulse wave velocities were determined to evaluate aortic, lower-limb, and upper-limb regional arterial stiffness, respectively. Correlation analysis between stiffness parameters and BP was done. Results. Compared to NW, OB subjects showed higher peripheral and central BP and carotid and femoral stiffness, reaching statistical significance in subjects aged 12 and older. Arterial stiffness differences disappeared when levels were normalized for BP. There were no differences in intrinsic arterial wall stiffness (elastic modulus, BP stiffness relationships, and regional stiffness parameters. Conclusion. OB associates with BP-dependent and age-related increase in carotid and femoral (but not brachial stiffness. Stiffness changes would not be explained by intrinsic arterial wall alterations but could be associated with the higher BP levels observed in obese children.

  18. Felipressina aumenta pressão arterial durante procedimento odontológico em pacientes hipertensos Felypressin increases blood pressure during dental procedures in hypertensive patients

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    Ana Lúcia Aparecida Bronzo

    2012-08-01

    Full Text Available FUNDAMENTO: A felipressina foi adicionada ao anestésico local para aumentar a duração do efeito anestésico e reduzir a toxicidade nos procedimentos dentários. No entanto, o efeito sobre a pressão arterial é incerta, e isso pode ser altamente relevante no tratamento dentário de pacientes hipertensos. OBJETIVO: Investigar o efeito da felipressina sobre a pressão arterial em pacientes hipertensos com pressão arterial controlada. MÉTODOS: Foram estudados 71 indivíduos com essas características e com necessidade de tratamento periodontal. Após 10 minutos de repouso, a anestesia local (prilocaína foi infiltrada com e sem adição de felipressina. Em seguida, uma raspagem subgengival profunda foi realizada. A pressão arterial foi medida por um equipamento oscilométrico automático (DIXTAL DX2010. Dez minutos após a administração do anestésico, o pico de ação anestésica foi gravado. O Inventário de Ansiedade Traço-Estado (IDATE foi utilizado para avaliar o traço de ansiedade nos pacientes. RESULTADOS: A pressão arterial sistólica aumentou após a anestesia, independentemente da associação com felipressina, durante todo o procedimento dentário (p BACKGROUND: Felypressin has been added to local anesthetic to increase the length of the anesthetic effect and reduce toxicity during dental procedures. However, the effect on blood pressure remains uncertain, and this may be highly relevant in the dental treatment of hypertensive patients. OBJECTIVE: To investigate the effect of felypressin on blood pressure in hypertensive patients with controlled BP. METHODS: 71 subjects with these characteristics and in need of periodontal treatment were studied. After 10 minutes of rest, local anesthesia (prilocaine was infiltrated with and without addition of felypressin. Then, a deep subgingival scaling was performed. Blood pressure was measured by an automated oscillometric device (DIXTAL DX2010. Ten minutes after the administration of the

  19. Deletion of Cyclooxygenase-2 in the mouse increases arterial blood pressure with no impairment in renal NO production in response to chronic high salt intake

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    Staehr, Mette; Hansen, Pernille B L; Madsen, Kirsten

    2013-01-01

    Experiments were designed to test the hypothesis that COX-2 activity attenuates the blood pressure increase during high NaCl intake by stimulation of eNOS-mediated NO synthesis in the kidney medulla. COX-2(-/-) (C57BL6) and (+/+) mice were fed a diet with 0.004% (LS) or 4% (HS) NaCl for 18 days....... Arterial blood pressure was recorded continuously using indwelling catheters. Food and water intake and diuresis were measured in metabolic cages. Urine osmolality and excretion of electrolytes, cGMP, cAMP and NOx were determined, as well as plasma NOx and cGMP. There was a significant dependence of blood...... pressure on salt intake and genotype: COX-2(-/-) exhibited higher blood pressure than COX-2(+/+) both on HS and LS intake. COX-2(+/+) littermates displayed an increase in blood pressure on HS vs. LS (102.3±1.1 mmHg vs. 91.9±0.9 mmHg) day and night. The mice exhibited significant blood pressure increases...

  20. Increased concentration of serum TNF alpha and its correlations with arterial blood pressure and indices of renal damage in dogs infected with Babesia canis.

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    Zygner, Wojciech; Gójska-Zygner, Olga; Bąska, Piotr; Długosz, Ewa

    2014-04-01

    Canine babesiosis is a tick-borne disease caused by parasites of the genus Babesia. Tumour necrosis factor alpha (TNF-α) is a cytokine that plays a role in the pathogenesis of canine babesiosis. In this study, the authors determined the concentration of serum TNF-α in 11 dogs infected with Babesia canis and calculated Spearman's rank correlations between the concentration of TNF-α and blood pressure, and between TNF-α and indices of renal damage such as: fractional excretion of sodium (FE(Na(+))), urinary creatinine to serum creatinine ratio (UCr/SCr), renal failure index (RFI), urine specific gravity (USG) and urinary protein to urinary creatinine ratio (UPC). The results demonstrated statistically significant strong negative correlations between TNF-α and systolic arterial pressure (r = -0.7246), diastolic arterial pressure (r = -0.6642) and mean arterial pressure (r = -0.7151). Serum TNF-α concentration was also statistically significantly correlated with FE(Na(+)) (r = 0.7056), UCr/SCr (r = -0.8199), USG (r = -0.8075) and duration of the disease (r = 0.6767). The results of this study show there is an increase of serum TNF-α concentration during canine babesiosis, and the increased TNF-α concentration has an influence on the development of hypotension and renal failure in canine babesiosis. This probably results from the fact that TNF-α is involved in the production of nitric oxide and induction of vasodilation and hypotension, which may cause renal ischaemia and hypoxia, and finally acute tubular necrosis and renal failure.

  1. Correlation of invasive central arterial pressure with peripheral arterial pressure and coronary sclerosis

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    吴琪

    2013-01-01

    Objective To study the consistency among non-invasive and invasive brachial artery pressure,radial artery pressure and invasive central arterial pressure,and to explore the correlation between the severe degree of coronary artery disease and invasive central aortic pressure.

  2. Reconstruction of brachial pressure from finger arterial pressure during orthostasis

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    Bogert, Lysander W J; Harms, Mark P M; Pott, Frank;

    2004-01-01

    In patients with recurrent syncope, monitoring of intra-arterial pressure during orthostatic stress testing is recommended because of the potentially sudden and rapid development of hypotension. Replacing brachial arterial pressure (BAP) by the non-invasively obtained finger arterial pressure (Fin...

  3. Reconstruction of brachial pressure from finger arterial pressure during orthostasis

    DEFF Research Database (Denmark)

    Bogert, Lysander W J; Harms, Mark P M; Pott, Frank

    2004-01-01

    In patients with recurrent syncope, monitoring of intra-arterial pressure during orthostatic stress testing is recommended because of the potentially sudden and rapid development of hypotension. Replacing brachial arterial pressure (BAP) by the non-invasively obtained finger arterial pressure (Fi...

  4. Low-level lead exposure increases systolic arterial pressure and endothelium-derived vasodilator factors in rat aortas.

    Directory of Open Access Journals (Sweden)

    Jonaina Fiorim

    Full Text Available Chronic lead exposure induces hypertension and alters endothelial function. However, treatment with low lead concentrations was not yet explored. We analyzed the effects of 7 day exposure to low lead concentrations on endothelium-dependent responses. Wistar rats were treated with lead (1st dose 4 µg/100 g, subsequent dose 0.05 µg/100 g, i.m. to cover daily loss or vehicle; blood levels attained at the end of treatment were 9.98 µg/dL. Lead treatment had the following effects: increase in systolic blood pressure (SBP; reduction of contractile response to phenylephrine (1 nM-100 µM of aortic rings; unaffected relaxation induced by acetylcholine (0.1 nM-300 µM or sodium nitroprusside (0.01 nM-0.3 µM. Endothelium removal, N(G-nitro-L-arginine methyl ester (100 µM and tetraethylammonium (2 mM increased the response to phenylephrine in treated rats more than in untreated rats. Aminoguanidine (50 µM increased but losartan (10 µM and enalapril (10 µM reduced the response to phenylephrine in treated rats. Lead treatment also increased aortic Na(+/K(+-ATPase functional activity, plasma angiotensin-converting enzyme (ACE activity, protein expression of the Na(+/K(+-ATPase alpha-1 subunit, phosphorylated endothelial nitric oxide synthase (p-eNOS, and inducible nitric oxide synthase (iNOS. Our results suggest that on initial stages of lead exposure, increased SBP is caused by the increase in plasma ACE activity. This effect is accompanied by increased p-eNOS, iNOS protein expression and Na(+/K(+-ATPase functional activity. These factors might be a compensatory mechanism to the increase in SBP.

  5. Chronic hypoxia increases arterial blood pressure and reduces adenosine and ATP induced vasodilatation in skeletal muscle in healthy humans

    DEFF Research Database (Denmark)

    Calbet, J A L; Boushel, Robert Christopher; Robach, P;

    2014-01-01

    into the femoral artery at sea level and then after 8-12 days of residence at 4559 m above sea level. At sea level, the infusions were carried out while the subjects breathed room air, acute hypoxia (FI O2 = 0.11) and hyperoxia (FI O2 = 1); and at altitude (FI O2 = 0.21 and 1). Skeletal muscle P2Y2 receptor...

  6. Increased intracranial pressure

    Science.gov (United States)

    ... patient's bedside in an emergency room or hospital. Primary care doctors may sometimes spot early symptoms of increased intracranial pressure such as headache, seizures, or other nervous system problems. An MRI ...

  7. Angiotensin II type 1a receptors in subfornical organ contribute towards chronic intermittent hypoxia-associated sustained increase in mean arterial pressure.

    Science.gov (United States)

    Saxena, Ashwini; Little, Joel T; Nedungadi, T Prashant; Cunningham, J Thomas

    2015-03-01

    Sleep apnea is associated with hypertension. The mechanisms contributing to a sustained increase in mean arterial pressure (MAP) even during normoxic awake-state remain unknown. Rats exposed to chronic intermittent hypoxia for 7 days, a model of the hypoxemia associated with sleep apnea, exhibit sustained increases in MAP even during the normoxic dark phase. Activation of the renin-angiotensin system (RAS) has been implicated in chronic intermittent hypoxia (CIH) hypertension. Since the subfornical organ (SFO) serves as a primary target for the central actions of circulating ANG II, we tested the effects of ANG II type 1a receptor (AT1aR) knockdown in the SFO on the sustained increase in MAP in this CIH model. Adeno-associated virus carrying green fluorescent protein (GFP) and small-hairpin RNA against either AT1aR or a scrambled control sequence (SCM) was stereotaxically injected in the SFO of rats. After recovery, MAP, heart rate, respiratory rate, and activity were continuously recorded using radiotelemetry. In the normoxic groups, the recorded variables did not deviate from the baseline values. Both CIH groups exhibited significant increases in MAP during CIH exposures (P SCM-injected group exhibited a sustained increase in MAP (P SCM-CIH group. Our data indicate that AT1aRs in the SFO are critical for the sustained elevation in MAP and increased FosB/ΔFosB expression in forebrain autonomic nuclei associated with CIH.

  8. Effects of San'o-shashin-to and the constituent herbal medicines on theophylline-induced increase in arterial blood pressure of rats.

    Science.gov (United States)

    Sanae, F; Komatsu, Y; Chisaki, K; Kido, T; Ishige, A; Hayashi, H

    2001-10-01

    San'o-shashin-to, composed of Scutellariae Radix, Coptidis Rhizoma and Rhei Rhizoma (volume ratio = 1:1:1), reduced an increase in arterial blood pressure of anesthetized rats induced by theophylline (5 mg/kg, i.v.). The hypotensive effect of San'o-shashin-to was produced in a dose dependent manner and was maximum at its 0.5 g/kg. Then the constituent herbal medicines were examined for their possible hypotensive effect. Scutellariae Radix of 0.2 g/kg slightly decreased in the blood presure. Rhei Rhizoma of 0.2 g/kg decreased in the blood pressure and the hypotensive effect was significantly produced even at the dose of 0.05 g/kg, while Coptidis Rhizoma had little effect. Among fractions of San'o-shashin-to separated by Diaion HP-20 column chromatography, the 50% methanol-eluted fraction had a large hypotensive effect. The 50% methanol-eluted fraction of Scutellariae Radix and Rhei Rhizoma were also effective and, especially, that of Rhei Rhizoma had a large hypotensive effect. In isometric tension study, Scutellariae Radix and Rhei Rhizoma (10-30 microg/ml) slightly exerted contractile and relaxant effects, respectively, on the phenylephrine-contracted endothelium-intact rat thoracic aorta. Coptidis Rhizoma (1-10 microg/ml) caused both endothelium-dependent and -independent relaxantion. These results suggest that the hypotensive effect of San'o-shashin-to is not mediated by the direct action on blood vessel but by other actions. Some components in Scutellariae Radix and Rhei Rhizoma, especially in the latter may play a main role in the hypotensive effect.

  9. Increasing Inflationary Pressure

    Institute of Scientific and Technical Information of China (English)

    Guo Yan

    2008-01-01

    @@ China's CPI rose to 8.7 percent in February after hitting 7.1 percent in January,creating a 12-year high,the National Bureau of Statistics said.The figure exceeded market expectations,as the Bank of China,the country's secondlargest lender,had predicted a rise of only 8.3 percent.The Consumer Price Index (CPI)is the main gauge of inflation,andthe high CPI over the last two months has put pressure on the government to take action to curb the price increases,and added even more diffculty to the task of reining in this year's inflation rate.

  10. Experimental exposure to diesel exhaust increases arterial stiffness in man

    Directory of Open Access Journals (Sweden)

    Newby David E

    2009-03-01

    Full Text Available Abstract Introduction Exposure to air pollution is associated with increased cardiovascular morbidity, although the underlying mechanisms are unclear. Vascular dysfunction reduces arterial compliance and increases central arterial pressure and left ventricular after-load. We determined the effect of diesel exhaust exposure on arterial compliance using a validated non-invasive measure of arterial stiffness. Methods In a double-blind randomized fashion, 12 healthy volunteers were exposed to diesel exhaust (approximately 350 μg/m3 or filtered air for one hour during moderate exercise. Arterial stiffness was measured using applanation tonometry at the radial artery for pulse wave analysis (PWA, as well as at the femoral and carotid arteries for pulse wave velocity (PWV. PWA was performed 10, 20 and 30 min, and carotid-femoral PWV 40 min, post-exposure. Augmentation pressure (AP, augmentation index (AIx and time to wave reflection (Tr were calculated. Results Blood pressure, AP and AIx were generally low reflecting compliant arteries. In comparison to filtered air, diesel exhaust exposure induced an increase in AP of 2.5 mmHg (p = 0.02 and in AIx of 7.8% (p = 0.01, along with a 16 ms reduction in Tr (p = 0.03, 10 minutes post-exposure. Conclusion Acute exposure to diesel exhaust is associated with an immediate and transient increase in arterial stiffness. This may, in part, explain the increased risk for cardiovascular disease associated with air pollution exposure. If our findings are confirmed in larger cohorts of susceptible populations, this simple non-invasive method of assessing arterial stiffness may become a useful technique in measuring the impact of real world exposures to combustion derived-air pollution.

  11. Increased perfusion pressure enhances the expression of endothelin (ETB) and angiotensin II (AT1, AT2) receptors in rat mesenteric artery smooth muscle cells

    DEFF Research Database (Denmark)

    Lindstedt, Isak; Xu, Cang-Bao; Zhang, Yaping;

    2009-01-01

    and luminally perfused in a perfusion chamber. After either exposure to no ("organ culture" (0 mmHg)), normal (85/75 mmHg) or high pressure (160/150 mmHg) at constant flow for 1-17 h, the vessel segments were snap frozen and real-time polymerase chain reaction was performed to quantify the ET- and AT-receptor m......In the present study, we hypothesized that changes in perfusion pressure result in altered expression of mRNA and protein encoding for the ETA-, ETB-, AT1- and AT2-receptors in rat mesenteric vessels. Segments of the rat mesenteric artery were cannulated with glass micropipettes, pressurized......RNA content, or immersed in a fixative solution, dehydrated, frozen, cut in a cryostat and immunohistology stained for ET- and AT-receptor protein. The mRNA expressions of ETB and of AT2 were significantly enhanced in vessels exposed to high perfusion pressure, compared with normal and no perfusion pressure...

  12. High Blood Pressure Increasing Worldwide

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_162977.html High Blood Pressure Increasing Worldwide And health risks may appear even ... of people around the world with elevated or high blood pressure increases, so do the number of deaths linked ...

  13. Distal shift of arterial pressure wave reflection sites with aging.

    Science.gov (United States)

    Sugawara, Jun; Hayashi, Koichiro; Tanaka, Hirofumi

    2010-11-01

    An early return of reflected waves, the backward propagation of the arterial pressure wave from the periphery to the heart, is associated with the augmentation of central pulse pressure and cardiovascular risks. The locations of arterial pressure wave reflection, along with arterial stiffening, have a major influence on the timing of the reflected wave. To determine the influence of aging on the location of a major reflection site, arterial length (via 3D artery tracing of MRI) and central (carotid-femoral) and peripheral (femoral-ankle) pulse wave velocities were measured in 208 adults varying in age. The major reflection site was detected by carotid-femoral pulse wave velocity and the reflected wave transit time (via carotid arterial pressure wave analysis). The length from the aortic valve to the major reflection site (eg, effective reflecting length) significantly increased with aging. The effective reflecting length normalized by the arterial length demonstrated that the major reflection sites were located between the aortic bifurcation and femoral site in most of the subjects. The normalized effective reflecting length did not alter with aging until 65 years of age and increased remarkably thereafter in men and women. The effective reflecting length was significantly and positively associated with the difference between central and peripheral pulse wave velocities (r=0.76). This correlation remained significant even when the influence of aortic pulse wave velocity was partial out (r=0.35). These results suggest that the major reflection site shifts distally with aging partly because of the closer matching of impedance provided by central and peripheral arterial stiffness.

  14. Clinical review: Interpretation of arterial pressure wave in shock states

    OpenAIRE

    Lamia, Bouchra; Chemla, Denis; Richard, Christian; Teboul, Jean-Louis

    2005-01-01

    In critically ill patients monitored with an arterial catheter, the arterial pressure signal provides two types of information that may help the clinician to interpret haemodynamic status better: the mean values of systolic, diastolic, mean and pulse pressures; and the magnitude of the respiratory variation in arterial pressure in patients undergoing mechanical ventilation. In this review we briefly discuss the physiological mechanisms responsible for arterial pressure generation, with specia...

  15. Peripheral arterial volume distensibility: significant differences with age and blood pressure measured using an applied external pressure.

    Science.gov (United States)

    Zheng, Dingchang; Murray, Alan

    2011-05-01

    A new arterial distensibility measurement technique was assessed in 100 healthy normotensive subjects. Arterial transmural pressures on the whole right arm were reduced with a 50 cm long cuff inflated to 10, 20, 30 and 40 mmHg. The electrocardiogram, and finger and ear photoplethysmograms were recorded simultaneously. Arm pulse propagation time, pulse wave velocity (PWV) and arterial volume distensibility were determined. With a 40 mmHg reduction in transmural pressure, arm pulse propagation time increased from 61 to 83 ms, PWV decreased from 12 to 8 m s(-1) and arterial distensibility increased from 0.102% to 0.232% per mmHg (all P pressures, arterial distensibility was significantly related to resting mean arterial pressure (MAP), diastolic blood pressure (DBP) and age, and for systolic blood pressure at 30 and 40 mmHg (all P pressure, arterial distensibility fell by 54% for a MAP increase from 75 to 105 mmHg, 57% for a DBP increase from 60 to 90 mmHg and 47% for an age increase from 20 to 70 years. These changes were more than double than those without cuff pressure. Our technique showed that systemic volume distensibility of the peripheral arm artery reduced with age, with a greater effect at higher external and lower transmural pressures.

  16. [Impact of periodontal disease on arterial pressure in diabetic mice].

    Science.gov (United States)

    Blasco-Baque, V; Kémoun, P; Loubieres, P; Roumieux, M; Heymes, C; Serino, M; Sixou, M; Burcelin, R

    2012-06-01

    Diabetes-driven cardiovascular diseases represent a high challenge for developed countries. Periodontal disease is strictly linked to the aforementioned diseases, due to its Gram negative-driven inflammation. Thus, we investigated the effects of periodontal disease on arterial pressure during the development of diabetes in mice. To this aim, C57BL/6 female mice were colonized with pathogens of periodontal tissue (Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum) for 1month, whereas another group of mice did not undergo the colonization. Subsequently, all mice were fed a high-fat carbohydrate-free diet for 3months. Then, arterial pressure was measured in vivo and a tomodensitometric analysis of mandibles was realized as well. Our results show increased mandibular bone-loss induced by colonization with periopathogens. In addition, periodontal infection augmented glucose-intolerance and systolic and diastolic arterial pressure, parameters already known to be affected by a fat-diet. In conclusion, we show here that periodontal disease amplifies metabolic troubles and deregulates arterial pressure, emerging as a new axis of metabolic investigation.

  17. Effect of psychological stress on blood pressure increase: a meta-analysis of cohort studies Efeito do estresse psicológico no aumento da pressão arterial: uma metanálise de estudos de coorte

    Directory of Open Access Journals (Sweden)

    Daniela Gasperin

    2009-04-01

    Full Text Available Studies have suggested that chronic exposure to stress may have an influence on increased blood pressure. A systematic review followed by a meta-analysis was conducted aiming to assess the effect of psychological stress on blood pressure increase. Research was mainly conducted in Ingenta, Psycinfo, PubMed, Scopus and Web of Science. Inclusion criteria were: published in any language; from January 1970 to December 2006; prospective cohort design; adults; main exposure psychological/emotional stress; outcome arterial hypertension or blood pressure increase > 3.5mmHg. A total of 2,043 studies were found, of which 110 were cohort studies. Of these, six were eligible and yielded 23 comparison groups and 34,556 subjects. Median follow-up time and loss to follow-up were 11.5 years and 21%. Results showed individuals who had stronger responses to stressor tasks were 21% more likely to develop blood pressure increase when compared to those with less strong responses (OR: 1.21; 95%CI: 1.14-1.28; p Estudos sugerem que a exposição crônica ao estresse tenha influência no aumento dos níveis pressóricos. Foi realizada uma revisão sistemática seguida de metanálise com o objetivo de avaliar o efeito do estresse psicológico no aumento da pressão arterial. As principais bases de dados utilizadas foram Ingenta, Psycinfo, PubMed, Scopus e Web of Science. Os critérios de inclusão foram: publicado entre janeiro de 1970 e dezembro de 2006, delineamento de coorte prospectiva, adultos, estresse psicológico/emocional como exposição principal, hipertensão arterial ou aumento na pressão arterial > 3,5mmHg como desfecho. A busca resultou em 2.043 artigos, sendo 110 coortes. Desses, seis eram elegíveis, os quais geraram 23 grupos de comparação e 34.556 sujeitos. A mediana do tempo de seguimento e do percentual de perdas foi 11,5 anos e 21%. Indivíduos com maior reação a tarefas estressoras possuíam 21% mais chances de apresentar aumento na press

  18. Arterial blood-pressure change and endogenous circulating substance P in man

    DEFF Research Database (Denmark)

    Henriksen, J H; Kastrup, J; Schaffalitzky De Muckadell, O B

    1985-01-01

    Substance P (SP) is a powerful vasodilator and this peptide is today considered to be a chemical messenger. The potential effects on circulating SP of acute changes in arterial blood-pressure was investigated in nine subjects. An increase in arterial mean blood-pressure (+33%, P less than 0.001, ...

  19. Body height and arterial pressure in seated and supine young males during +2 G centrifugation

    DEFF Research Database (Denmark)

    Arvedsen, Sine K.; Eiken, Ola; Kölegård, Roger;

    2015-01-01

    by the use of a human centrifuge would increase mean arterial pressure (MAP) more in tall than in short males in the seated position. In short (162-171cm, n=8) and tall (194-203cm, n=10) healthy males (18-41yr), brachial arterial pressure, heart rate (HR) and cardiac output were measured during +2G...

  20. Cigarette smoke exposure induced pulmonary artery pressure increase through inhibiting Kv1.5 and Kv2.1 mRNA expression in rat pulmonary artery smooth muscles

    Institute of Scientific and Technical Information of China (English)

    林纯意

    2012-01-01

    Objective To investigate the effect of cigarette smoke exposure on Kv1.5 and Kv2.1 mRNA expression in rat pulmonary arterial smooth muscle cells(PASMCs), and further to clarify the possible mechanism of cigarette smoking induced pulmonary arterial hypertension. Methods Primary

  1. Modifiable risk factors for increased arterial stiffness in outpatient nephrology.

    Science.gov (United States)

    Elewa, Usama; Fernandez-Fernandez, Beatriz; Alegre, Raquel; Sanchez-Niño, Maria D; Mahillo-Fernández, Ignacio; Perez-Gomez, Maria Vanessa; El-Fishawy, Hussein; Belal, Dawlat; Ortiz, Alberto

    2015-01-01

    Arterial stiffness, as measured by pulse wave velocity (PWV), is an independent predictor of cardiovascular events and mortality. Arterial stiffness increases with age. However, modifiable risk factors such as smoking, BP and salt intake also impact on PWV. The finding of modifiable risk factors may lead to the identification of treatable factors, and, thus, is of interest to practicing nephrologist. We have now studied the prevalence and correlates of arterial stiffness, assessed by PWV, in 191 patients from nephrology outpatient clinics in order to identify modifiable risk factors for arterial stiffness that may in the future guide therapeutic decision-making. PWV was above normal levels for age in 85/191 (44.5%) patients. Multivariate analysis showed that advanced age, systolic BP, diabetes mellitus, serum uric acid and calcium polystyrene sulfonate therapy or calcium-containing medication were independent predictors of PWV. A new parameter, Delta above upper limit of normal PWV (Delta PWV) was defined to decrease the weight of age on PWV values. Delta PWV was calculated as (measured PWV) - (upper limit of the age-adjusted PWV values for the general population). Mean±SD Delta PWV was 0.76±1.60 m/sec. In multivariate analysis, systolic blood pressure, active smoking and calcium polystyrene sulfonate therapy remained independent predictors of higher delta PWV, while age, urinary potassium and beta blocker therapy were independent predictors of lower delta PWV. In conclusion, arterial stiffness was frequent in nephrology outpatients. Systolic blood pressure, smoking, serum uric acid, calcium-containing medications, potassium metabolism and non-use of beta blockers are modifiable factors associated with increased arterial stiffness in Nephrology outpatients.

  2. Modifiable risk factors for increased arterial stiffness in outpatient nephrology.

    Directory of Open Access Journals (Sweden)

    Usama Elewa

    Full Text Available Arterial stiffness, as measured by pulse wave velocity (PWV, is an independent predictor of cardiovascular events and mortality. Arterial stiffness increases with age. However, modifiable risk factors such as smoking, BP and salt intake also impact on PWV. The finding of modifiable risk factors may lead to the identification of treatable factors, and, thus, is of interest to practicing nephrologist. We have now studied the prevalence and correlates of arterial stiffness, assessed by PWV, in 191 patients from nephrology outpatient clinics in order to identify modifiable risk factors for arterial stiffness that may in the future guide therapeutic decision-making. PWV was above normal levels for age in 85/191 (44.5% patients. Multivariate analysis showed that advanced age, systolic BP, diabetes mellitus, serum uric acid and calcium polystyrene sulfonate therapy or calcium-containing medication were independent predictors of PWV. A new parameter, Delta above upper limit of normal PWV (Delta PWV was defined to decrease the weight of age on PWV values. Delta PWV was calculated as (measured PWV - (upper limit of the age-adjusted PWV values for the general population. Mean±SD Delta PWV was 0.76±1.60 m/sec. In multivariate analysis, systolic blood pressure, active smoking and calcium polystyrene sulfonate therapy remained independent predictors of higher delta PWV, while age, urinary potassium and beta blocker therapy were independent predictors of lower delta PWV. In conclusion, arterial stiffness was frequent in nephrology outpatients. Systolic blood pressure, smoking, serum uric acid, calcium-containing medications, potassium metabolism and non-use of beta blockers are modifiable factors associated with increased arterial stiffness in Nephrology outpatients.

  3. Porcine radial artery decellularization by high hydrostatic pressure.

    Science.gov (United States)

    Negishi, Jun; Funamoto, Seiichi; Kimura, Tsuyoshi; Nam, Kwangoo; Higami, Tetsuya; Kishida, Akio

    2015-11-01

    Many types of decellularized tissues have been studied and some have been commercially used in clinics. In this study, small-diameter vascular grafts were made using HHP to decellularize porcine radial arteries. One decellularization method, high hydrostatic pressure (HHP), has been used to prepare the decellularized porcine tissues. Low-temperature treatment was effective in preserving collagen and collagen structures in decellularized porcine carotid arteries. The collagen and elastin structures and mechanical properties of HHP-decellularized radial arteries were similar to those of untreated radial arteries. Xenogeneic transplantation (into rats) was performed using HHP-decellularized radial arteries and an untreated porcine radial artery. Two weeks after transplantation into rat carotid arteries, the HHP-decellularized radial arteries were patent and without thrombosis. In addition, the luminal surface of each decellularized artery was covered by recipient endothelial cells and the arterial medium was fully infiltrated with recipient cells.

  4. Determinants of an elevated pulmonary arterial pressure in patients with pulmonary arterial hypertension.

    Science.gov (United States)

    Sakao, Seiichiro; Voelkel, Norbert F; Tanabe, Nobuhiro; Tatsumi, Koichiro

    2015-01-01

    Given the difficulty of diagnosing early-stage pulmonary arterial hypertension (PAH) due to the lack of signs and symptoms, and the risk of an open lung biopsy, the precise pathological features of presymptomatic stage lung tissue remain unknown. It has been suggested that the maximum elevation of the mean pulmonary arterial pressure (P pa) is achieved during the early symptomatic stage, indicating that the elevation of the mean P pa is primarily driven by the pulmonary vascular tone and/or some degree of pulmonary vascular remodeling completed during this stage. Recently, the examination of a rat model of severe PAH suggested that the severe PAH may be primarily determined by the presence of intimal lesions and/or the vascular tone in the early stage. Human data seem to indicate that intimal lesions are essential for the severely increased pulmonary arterial blood pressure in the late stage of the disease.However, many questions remain. For instance, how does the pulmonary hemodynamics change during the course of the disease, and what drives the development of severe PAH? Although it is generally acknowledged that both pulmonary vascular remodeling and the vascular tone are important determinants of an elevated pulmonary arterial pressure, which is the root cause of the time-dependent progression of the disease? Here we review the recent histopathological concepts of PAH with respect to the progression of the lung vascular disease.

  5. Increased perfusion pressure enhances the expression of endothelin (ETB) and angiotensin II (AT1, AT2) receptors in rat mesenteric artery smooth muscle cells

    DEFF Research Database (Denmark)

    Lindstedt, Isak; Xu, Cang-Bao; Zhang, Yaping;

    2009-01-01

    and luminally perfused in a perfusion chamber. After either exposure to no ("organ culture" (0 mmHg)), normal (85/75 mmHg) or high pressure (160/150 mmHg) at constant flow for 1-17 h, the vessel segments were snap frozen and real-time polymerase chain reaction was performed to quantify the ET- and AT-receptor m......RNA content, or immersed in a fixative solution, dehydrated, frozen, cut in a cryostat and immunohistology stained for ET- and AT-receptor protein. The mRNA expressions of ETB and of AT2 were significantly enhanced in vessels exposed to high perfusion pressure, compared with normal and no perfusion pressure...

  6. Carotid artery disease and low cerebral perfusion pressure

    DEFF Research Database (Denmark)

    Schroeder, T; Utzon, N P; Aabech, J

    1990-01-01

    Direct internal carotid artery blood pressure measurements in patients undergoing carotid endarterectomy identified 49 patients, among 239 consecutive cases (21%), who had a reduction in perfusion pressure of 20% or more. The clinical history, objective findings and angiographic data were compared...... with those of a control group of a further 49 patients selected from the remaining patients operated on over the same period. The two groups were compared for short- and long-term outcome of surgery. We were unable to delineate a symptomatic neurological profile that identified patients with low perfusion...... pressures. Surgery in patients with low perfusion pressures seemed to be associated with an increased complication rate (12% versus 4%), although this was not statistically significant. Definite postoperative improvements in persisting neurological deficits were observed only in one patient. Long...

  7. Clitoral blood flow increases following vaginal pressure stimulation.

    Science.gov (United States)

    Lavoisier, P; Aloui, R; Schmidt, M H; Watrelot, A

    1995-02-01

    The vascular responses of clitoral arteries to vaginal pressure stimulation in 10 volunteer women were evaluated by Doppler ultrasonography. Pressure stimulations (20-160 mm Hg) along the lower third of the vagina increased blood velocity and flow into clitoral arteries in 9 of the 10 women. The latency and duration of the Doppler responses ranged from 0.1 to 1.6 sec and from 3.2 to 9.5 sec, respectively, and the response was associated with a blood flow increase of 4 to 11 times the baseline prestimulation level. This response parallels that recorded in the cavernous arteries in men when a similar range of pressure stimulations are applied to the glans penis. Similar responses evoked in the male and female suggest a sexual synergy that may occur during intercourse in that such physiological responses and reflexes may be reciprocally reinforced.

  8. From Newborn to Senescence Morphological and Functional Remodeling Leads to Increased Contractile Capacity of Arteries.

    Science.gov (United States)

    Ivic, Ivan; Vamos, Zoltan; Cseplo, Peter; Koller, Akos

    2017-04-01

    Aging induces substantial morphological and functional changes in vessels. We hypothesized that due to morphological remodeling the total contractile forces of arteries increase, especially in older age as a function of age. Mean arterial blood pressure of rats and morphological and functional characteristics of isolated carotid arteries rats, from newborn to senescent, were assessed. The arterial blood pressure of rats increased significantly from 0.25 to the age of 6 months, and then it reached a level, which was maintained until age of 30 months. Wall lumen and wall thickness increased with age, mostly due to media (smooth muscle) thickening, whereas wall tension gradually reduced with age. Contractions of arteries to nonreceptor-mediated vasomotor agent (KCl, 60mM) increased in three consecutive age groups, whereas contractility first increased (until 2 months), then it did not change further with aging. Norepinephrine-induced contractions initially increased in young age and then did not change further in older age. These findings suggest that during normal aging due to remodeling of arterial wall (smooth muscle) the contractile capacity of arteries increases, which seems to be independent from systemic blood pressure. Thus, arterial remodeling can favor the development of increased circulatory resistance in older age.

  9. Harmonics tracking of intracranial and arterial blood pressure waves.

    Science.gov (United States)

    Shahsavari, Sima; McKelvey, Tomas

    2008-01-01

    Considering cardiorespiratory interaction and heart rate variability, a new approach is proposed to decompose intracranial pressure and arterial blood pressure to their different harmonics. The method is based on tracking the amplitudes of the harmonics by a Kalman filter based tracking algorithm. The algorithm takes benefit of combined frequency estimation technique which uses both Fast Fourier Transform and RR-interval detection. The result would be of use in intracranial pressure and arterial blood pressure waveform analysis as well as other investigations which need to estimate contribution of specific harmonic in above mentioned signals such as Pressure-Volume Compensatory Reserve assessment.

  10. A new technique for assessing arterial pressure wave forms and central pressure with tissue Doppler

    Science.gov (United States)

    Haluska, Brian A; Jeffriess, Leanne; Mottram, Phillip M; Carlier, Stephane G; Marwick, Thomas H

    2007-01-01

    Background Non-invasive assessment of arterial pressure wave forms using applanation tonometry of the radial or carotid arteries can be technically challenging and has not found wide clinical application. 2D imaging of the common carotid arteries is routinely used and we sought to determine whether arterial waveform measurements could be derived from tissue Doppler imaging (TDI) of the carotid artery. Methods We studied 91 subjects (52 men, age 52 ± 14 years) with and without cardiovascular disease. Tonometry was performed on the carotid artery simultaneously with pulsed wave Doppler of the LVOT and acquired digitally. Longitudinal 2D images of the common carotid artery with and without TDI were also acquired digitally and both TDI and tonometry were calibrated using mean and diastolic cuff pressure and analysed off line. Results Correlation between central pressure by TDI and tonometry was excellent for maximum pressure (r = 0.97, p < 0.0001). The mean differences between central pressures derived by TDI and tonometry were minimal (systolic 5.36 ± 5.5 mmHg; diastolic 1.2 ± 1.2 mmHg). Conclusion Imaging of the common carotid artery motion with tissue Doppler may permit acquisition of a waveform analogous to that from tonometry. This method may simplify estimation of central arterial pressure and calculation of total arterial compliance. PMID:17266772

  11. Strength training reduces arterial blood pressure but not sympathetic neural activity in young normotensive subjects

    Science.gov (United States)

    Carter, Jason R.; Ray, Chester A.; Downs, Emily M.; Cooke, William H.

    2003-01-01

    The effects of resistance training on arterial blood pressure and muscle sympathetic nerve activity (MSNA) at rest have not been established. Although endurance training is commonly recommended to lower arterial blood pressure, it is not known whether similar adaptations occur with resistance training. Therefore, we tested the hypothesis that whole body resistance training reduces arterial blood pressure at rest, with concomitant reductions in MSNA. Twelve young [21 +/- 0.3 (SE) yr] subjects underwent a program of whole body resistance training 3 days/wk for 8 wk. Resting arterial blood pressure (n = 12; automated sphygmomanometer) and MSNA (n = 8; peroneal nerve microneurography) were measured during a 5-min period of supine rest before and after exercise training. Thirteen additional young (21 +/- 0.8 yr) subjects served as controls. Resistance training significantly increased one-repetition maximum values in all trained muscle groups (P training did not affect MSNA or heart rate. Arterial blood pressures and MSNA were unchanged, but heart rate increased after 8 wk of relative inactivity for subjects in the control group (61 +/- 2 to 67 +/- 3 beats/min; P = 0.01). These results indicate that whole body resistance exercise training might decrease the risk for development of cardiovascular disease by lowering arterial blood pressure but that reductions of pressure are not coupled to resistance exercise-induced decreases of sympathetic tone.

  12. Intraspecific scaling of arterial blood pressure in the Burmese python.

    Science.gov (United States)

    Enok, Sanne; Slay, Christopher; Abe, Augusto S; Hicks, James W; Wang, Tobias

    2014-07-01

    Interspecific allometric analyses indicate that mean arterial blood pressure (MAP) increases with body mass of snakes and mammals. In snakes, MAP increases in proportion to the increased distance between the heart and the head, when the heart-head vertical distance is expressed as ρgh (where ρ is the density of blood, G: is acceleration due to gravity and h is the vertical distance above the heart), and the rise in MAP is associated with a larger heart to normalize wall stress in the ventricular wall. Based on measurements of MAP in Burmese pythons ranging from 0.9 to 3.7 m in length (0.20-27 kg), we demonstrate that although MAP increases with body mass, the rise in MAP is merely half of that predicted by heart-head distance. Scaling relationships within individual species, therefore, may not be accurately predicted by existing interspecific analyses.

  13. Characterization and calibration of the central arterial pressure waveform obtained from vibrocardiographic signal

    Science.gov (United States)

    Casacanditella, L.; Cosoli, G.; Casaccia, S.; Rohrbaugh, J. W.; Scalise, L.; Tomasini, E. P.

    2016-06-01

    Laser Doppler Vibrometry (LDV) has been demonstrated to be a non-contact technique with high sensitivity, able to measure the skin vibrations related to cardiac activity. The obtainable mechanical signal (i.e. a velocity signal), VibroCardioGram (VCG), is able to provide significant physiological parameters, such as Heart Rate (HR). In this work, the authors aim to present a non-contact measurement method to obtain the arterial blood pressure signal from the mechanical vibrations assessed by LDV, in a central district of the arterial tree, such as carotid artery. In fact, in this way it is possible to indirectly assess Central Arterial Blood Pressure (CABP), which indicates the hemodynamic load on the heart, so that it is considered an important index predicting the cardiac risk of a subject. The measurement setup involves the use of an oscillometric cuff, to measure peripheral blood pressure at the radial artery level. Diastolic and Mean Arterial Pressure (MAP) at radial level were used to calibrate the integrated LDV signal (i.e. a displacement signal). As regard calibration, an exponential mathematical model was adopted to derive the pressure waveform from the displacement of the vessel detected by LDV. Results show an average difference of around 20% between systolic pressure measured at brachial level (i.e. peripheral pressure value) and systolic pressure derived from VCG signal measured over the carotid artery (i.e. central pressure). This is a physiological difference, consistent with the literature about the physiological increase of Systolic Blood Pressure (SBP) and Pressure Pulse (PP) at increased distances from the heart. However, this non-contact technique is affected by movement artifacts and by reflection phenomena not related to the studied vessel and so it is necessary to account of such issues in the results.

  14. Effects of hypoproteinemia on renal hemodynamics, arterial pressure, and fluid volume

    Energy Technology Data Exchange (ETDEWEB)

    Manning, R.D. Jr.

    1987-01-01

    The effects of long-term hypoproteinemia on renal hemodynamics, arterial pressure, and fluid volume were studied in eight conscious dogs over a 34-day period. Plasma protein concentration (PPC) was decreased by daily plasmapheresis, and the effects of decreasing and increasing sodium intake were measured. By the 12th day of plasmapheresis PPC had decreased to 2.5 g/dl from a control value of 7.2 g/dl, mean arterial pressure had decreased to 78% of control, glomerular filtration rate (GFR) was 75.2% of control, and urinary sodium excretion was decreased. By day 18 of plasmapheresis, estimated renal plasma flow (ERPF) was decreased to 60% of control due to the decreased arterial pressure and an increase in renal vascular resistance. GFR and ERPF were determined from the total clearance of (/sup 125/I)iothalamate and (/sup 131/I)iodohippurate. Also, plasma renin activity and plasma aldosterone concentration were both increased, and the relationship between mean arterial pressure and urinary sodium excretion was distinctly shifted to the left along the arterial pressure axis. In contradistinction to acute experiments, chronic hypoproteinemia results in decreases in GFR, ERPF, and urinary sodium excretion and has marked effects on both fluid volume and arterial pressure regulation.

  15. Femoral artery pressure measurement to predict the outcome of arterial surgery in patients with multilevel disease

    DEFF Research Database (Denmark)

    Faris, I; Tønnesen, K H; Agerskov, K;

    1982-01-01

    Direct measurement of the femoral artery pressure before operation has been used to predict the postoperative change in ankle and toe pressure in 102 limbs (83 patients) that underwent aortoiliac surgery for the treatment of atherosclerotic occlusion or stenosis affecting both the aortoiliac...... and femoral artery segments. Rest pain or gangrene was present in 74 limbs. In 26 other limbs simultaneous aortoiliac and femoral artery reconstructions were performed. The changes in both toe and ankle pressures could be confidently predicted from the preoperative data. A predicted toe pressure of lower than...... 25 mm Hg was associated with a high probability that amputation would be required. The chances of an amputation were less than 3% if a toe pressure higher than 40 mm Hg was predicted. If the predicted ankle pressure index was lower than 0.56, there was a 90% chance that intermittent claudication...

  16. [Features of arterial blood pressure in elderly persons of different ethnic groups in Yakutsk].

    Science.gov (United States)

    Nikitin, Iu P; Tatarinova, O V; Neustroeva, V N; Shcherbakova, L V; Sidorov, A S

    2013-01-01

    The differences in arterial blood pressure in the sample of population in the age of 60 and older of different ethnic groups in Yakutsk, as well as its connection with the other cardiovascular diseases risk factors have been analyzed. It was shown that the average values of systolic and diastolic blood pressure in subsample of the Yakuts appeared to be lower than in Caucasoid gerontic persons. The average values of systolic arterial blood pressure both in the Yakuts and in the Caucasoids were detected higher than normal values in all age-dependent subgroups. The average values of diastolic blood pressure in both ethnic groups were within the limits of high normal level. From 60 to 90 years and older the decrease in systolic and diastolic arterial blood pressure was detected; it was more marked in Caucasoid gerontic persons. The average values of pulse pressure in the Yakuts and in the Caucasoids appeared to be higher than the existing standard and didn't have any differences in ethnic groups. In both ethnical subsamples, pulse pressure values increase was observed in persons of 60-89 years old and its decrease after 90. Persons with overweight, obesity, central (abdominal) obesity, dyslypoproteidemias irrespective of belonging to ethnical group were characterized as having higher levels of arterial blood pressure. Statistically significant differences in the levels of arterial blood pressure in the Yakuts and in the Caucasoids depending on hyperglycemia, smoking, the presence of burdened anamnesis, educational level, marital status was not detected.

  17. [Chronobiology of blood pressure and chronopharmacotherapy of arterial hypertension].

    Science.gov (United States)

    Schmieder, R E; Bramlage, P; Schunkert, H

    2012-02-01

    Arterial blood pressure is subject to a circadian rhythm that results in a fall of blood pressure during the night. In patients with diabetes, renal insufficiency, left-ventricular hypertrophy, sleep apnea, hypertension of pregnancy, and different forms of secondary hypertension a nocturnal fall of blood pressure is even abandoned or reverted. Diagnosis is made using 24-h blood pressure measurement, which is however used not frequently enough for a clinical assessment or adjustment of therapy. An adaption of the selection or the time of administration of antihypertensive drugs with respect to the circadian rhythm is beneficial to control blood pressure and reduce cardiovascular morbidity. This is particularly true for patients with an a non- or inverted dipping blood pressure pattern, in which the bedtime dosing may result in a normalization of blood pressure and restoration of a normal circadian rhythm. The present manuscript reviews the chronopharmacotherapy of arterial hypertension and grant practical recommendations for their translation into clinical practice.

  18. Dopexamine increases internal mammary artery blood flow following coronary artery bypass grafting.

    LENUS (Irish Health Repository)

    Flynn, Michael J

    2012-02-03

    OBJECTIVE: Vasoactive agents and inotropes influence conduit-coronary blood flow following coronary artery bypass grafting (CABG). It was hypothesized that dopexamine hydrochloride, a dopamine A-1 (DA-1) and beta(2) agonist would increase conduit-coronary blood flow. A prospective randomized double blind clinical trial was carried out to test this hypothesis. DA-1 receptors have previously been localized to human left ventricle. METHODS: Twenty-six American Society of Anaesthesiology class 2-3 elective coronary artery bypass graft patients who did not require inotropic support on separation from cardiopulmonary bypass (CPB) were studied. According to a randomized allocation patients received either dopexamine (1 microg\\/kg per min) or placebo (saline) by intravenous infusion for 15 min. Immediately prior to and at 5,10 and 15 min of infusion, blood flow through the internal mammary and vein grafts (Transit time flow probes, Transonic Ltd.), heart rate, cardiac index, mean arterial pressure and pulmonary haemodynamics were noted. The data were analysed using multivariate analysis of variance. RESULTS: Low-dose dopexamine (1 microg\\/kg per min) caused a significant increase in mammary graft blood flow compared to placebo at 15 min of infusion (P=0.028, dopexamine group left internal mammary artery (LIMA) flow of 43.3+\\/-14.2 ml\\/min, placebo group LIMA flow at 26.1+\\/-16.3 ml\\/min). Dopexamine recipients demonstrated a non-significant trend to increased saphenous vein graft flow (P=0.059). Increased heart rate was the only haemodynamic change induced by dopexamine (P=0.004, dopexamine group at 85.2+\\/-9.6 beats\\/min and placebo group at 71.1+\\/-7.6 beats\\/min after 15 min of infusion). CONCLUSION: This study demonstrates that administration of dopexamine (1 microg\\/kg per min) was associated with a significant increase in internal mammary artery graft blood flow with mild increase in heart rate being the only haemodynamic change. Low-dose dopexamine may

  19. Heart and Artery Damage and High Blood Pressure

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More How High Blood Pressure Can Lead to a Heart Attack Updated:Dec ... sheet This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP • Know Your ...

  20. Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure

    NARCIS (Netherlands)

    Wain, Louise V; Verwoert, Germaine C; O'Reilly, Paul F; Shi, Gang; Johnson, Toby; Johnson, Andrew D; Bochud, Murielle; Rice, Kenneth M; Henneman, Peter; Smith, Albert V; Ehret, Georg B; Amin, Najaf; Larson, Martin G; Mooser, Vincent; Hadley, David; Dörr, Marcus; Bis, Joshua C; Aspelund, Thor; Esko, Tõnu; Janssens, A Cecile J W; Zhao, Jing Hua; Heath, Simon; Laan, Maris; Fu, Jingyuan; Pistis, Giorgio; Luan, Jian'an; Arora, Pankaj; Lucas, Gavin; Pirastu, Nicola; Pichler, Irene; Jackson, Anne U; Webster, Rebecca J; Zhang, Feng; Peden, John F; Schmidt, Helena; Tanaka, Toshiko; Campbell, Harry; Igl, Wilmar; Milaneschi, Yuri; Hottenga, Jouke-Jan; Vitart, Veronique; Chasman, Daniel I; Trompet, Stella; Bragg-Gresham, Jennifer L; Alizadeh, Behrooz Z; Chambers, John C; Guo, Xiuqing; Lehtimäki, Terho; Kühnel, Brigitte; Lopez, Lorna M; Polašek, Ozren; Boban, Mladen; Nelson, Christopher P; Morrison, Alanna C; Pihur, Vasyl; Ganesh, Santhi K; Hofman, Albert; Kundu, Suman; Mattace-Raso, Francesco U S; Rivadeneira, Fernando; Sijbrands, Eric J G; Uitterlinden, Andre G; Hwang, Shih-Jen; Vasan, Ramachandran S; Wang, Thomas J; Bergmann, Sven; Vollenweider, Peter; Waeber, Gérard; Laitinen, Jaana; Pouta, Anneli; Zitting, Paavo; McArdle, Wendy L; Kroemer, Heyo K; Völker, Uwe; Völzke, Henry; Glazer, Nicole L; Taylor, Kent D; Harris, Tamara B; Alavere, Helene; Haller, Toomas; Keis, Aime; Tammesoo, Mari-Liis; Aulchenko, Yurii; Barroso, Inês; Khaw, Kay-Tee; Galan, Pilar; Hercberg, Serge; Lathrop, Mark; Eyheramendy, Susana; Org, Elin; Sõber, Siim; Lu, Xiaowen; Nolte, Ilja M; Penninx, Brenda W; Corre, Tanguy; Masciullo, Corrado; Sala, Cinzia; Groop, Leif; Voight, Benjamin F; Melander, Olle; O'Donnell, Christopher J; Salomaa, Veikko; d'Adamo, Adamo Pio; Fabretto, Antonella; Faletra, Flavio; Ulivi, Sheila; Del Greco, Fabiola M; Facheris, Maurizio; Collins, Francis S; Bergman, Richard N; Beilby, John P; Hung, Joseph; Musk, A William; Mangino, Massimo; Shin, So-Youn; Soranzo, Nicole; Watkins, Hugh; Goel, Anuj; Hamsten, Anders; Gider, Pierre; Loitfelder, Marisa; Zeginigg, Marion; Hernandez, Dena; Najjar, Samer S; Navarro, Pau; Wild, Sarah H; Corsi, Anna Maria; Singleton, Andrew; de Geus, Eco J C; Willemsen, Gonneke; Parker, Alex N; Rose, Lynda M; Buckley, Brendan; Stott, David; Orru, Marco; Uda, Manuela; van der Klauw, Melanie M; Zhang, Weihua; Li, Xinzhong; Scott, James; Chen, Yii-Der Ida; Burke, Gregory L; Kähönen, Mika; Viikari, Jorma; Döring, Angela; Meitinger, Thomas; Davies, Gail; Starr, John M; Emilsson, Valur; Plump, Andrew; Lindeman, Jan H; Hoen, Peter A C 't; König, Inke R; Felix, Janine F; Clarke, Robert; Hopewell, Jemma C; Ongen, Halit; Breteler, Monique; Debette, Stéphanie; Destefano, Anita L; Fornage, Myriam; Mitchell, Gary F; Smith, Nicholas L; Holm, Hilma; Stefansson, Kari; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Samani, Nilesh J; Preuss, Michael; Rudan, Igor; Hayward, Caroline; Deary, Ian J; Wichmann, H-Erich; Raitakari, Olli T; Palmas, Walter; Kooner, Jaspal S; Stolk, Ronald P; Jukema, J Wouter; Wright, Alan F; Boomsma, Dorret I; Bandinelli, Stefania; Gyllensten, Ulf B; Wilson, James F; Ferrucci, Luigi; Schmidt, Reinhold; Farrall, Martin; Spector, Tim D; Palmer, Lyle J; Tuomilehto, Jaakko; Pfeufer, Arne; Gasparini, Paolo; Siscovick, David; Altshuler, David; Loos, Ruth J F; Toniolo, Daniela; Snieder, Harold; Gieger, Christian; Meneton, Pierre; Wareham, Nicholas J; Oostra, Ben A; Metspalu, Andres; Launer, Lenore; Rettig, Rainer; Strachan, David P; Beckmann, Jacques S; Witteman, Jacqueline C M; Erdmann, Jeanette; van Dijk, Ko Willems; Boerwinkle, Eric; Boehnke, Michael; Ridker, Paul M; Jarvelin, Marjo-Riitta; Chakravarti, Aravinda; Abecasis, Goncalo R; Gudnason, Vilmundur; Newton-Cheh, Christopher; Levy, Daniel; Munroe, Patricia B; Psaty, Bruce M; Caulfield, Mark J; Rao, Dabeeru C; Tobin, Martin D; Elliott, Paul; van Duijn, Cornelia M

    2011-01-01

    Numerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,607), we ident

  1. Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure

    NARCIS (Netherlands)

    Wain, Louise V.; Verwoert, Germaine C.; O'Reilly, Paul F.; Shi, Gang; Johnson, Toby; Johnson, Andrew D.; Bochud, Murielle; Rice, Kenneth M.; Henneman, Peter; Smith, Albert V.; Ehret, Georg B.; Amin, Najaf; Larson, Martin G.; Mooser, Vincent; Hadley, David; Doerr, Marcus; Bis, Joshua C.; Aspelund, Thor; Esko, Tonu; Janssens, A. Cecile J. W.; Zhao, Jing Hua; Heath, Simon; Laan, Maris; Fu, Jingyuan; Pistis, Giorgio; Luan, Jian'an; Arora, Pankaj; Lucas, Gavin; Pirastu, Nicola; Pichler, Irene; Jackson, Anne U.; Webster, Rebecca J.; Zhang, Feng; Peden, John F.; Schmidt, Helena; Tanaka, Toshiko; Campbell, Harry; Igl, Wilmar; Milaneschi, Yuri; Hottenga, Jouke-Jan; Vitart, Veronique; Chasman, Daniel I.; Trompet, Stella; Bragg-Gresham, Jennifer L.; Alizadeh, Behrooz Z.; Chambers, John C.; Guo, Xiuqing; Lehtimaki, Terho; Kuehnel, Brigitte; Lopez, Lorna M.; Polasek, Ozren; Boban, Mladen; Nelson, Christopher P.; Morrison, Alanna C.; Pihur, Vasyl; Ganesh, Santhi K.; Hofman, Albert; Kundu, Suman; Mattace-Raso, Francesco U. S.; Rivadeneira, Fernando; Sijbrands, Eric J. G.; Uitterlinden, Andre G.; Hwang, Shih-Jen; Vasan, Ramachandran S.; Wang, Thomas J.; Bergmann, Sven; Vollenweider, Peter; Waeber, Gerard; Laitinen, Jaana; Pouta, Anneli; Zitting, Paavo; McArdle, Wendy L.; Kroemer, Heyo K.; Voelker, Uwe; Voelzke, Henry; Glazer, Nicole L.; Taylor, Kent D.; Harris, Tamara B.; Alavere, Helene; Haller, Toomas; Keis, Aime; Tammesoo, Mari-Liis; Aulchenko, Yurii; Barroso, Ines; Khaw, Kay-Tee; Galan, Pilar; Hercberg, Serge; Lathrop, Mark; Eyheramendy, Susana; Org, Elin; Sober, Siim; Lu, Xiaowen; Nolte, Ilja M.; Penninx, Brenda W.; Corre, Tanguy; Masciullo, Corrado; Sala, Cinzia; Groop, Leif; Voight, Benjamin F.; Melander, Olle; O'Donnell, Christopher J.; Salomaa, Veikko; d'Adamo, Adamo Pio; Fabretto, Antonella; Faletra, Flavio; Ulivi, Sheila; Del Greco, Fabiola M.; Facheris, Maurizio; Collins, Francis S.; Bergman, Richard N.; Beilby, John P.; Hung, Joseph; Musk, A. William; Mangino, Massimo; Shin, So-Youn; Soranzo, Nicole; Watkins, Hugh; Goel, Anuj; Hamsten, Anders; Gider, Pierre; Loitfelder, Marisa; Zeginigg, Marion; Hernandez, Dena; Najjar, Samer S.; Navarro, Pau; Wild, Sarah H.; Corsi, Anna Maria; Singleton, Andrew; de Geus, Eco J. C.; Willemsen, Gonneke; Parker, Alex N.; Rose, Lynda M.; Buckley, Brendan; Stott, David; Orru, Marco; Uda, Manuela; van der Klauw, Melanie M.; Zhang, Weihua; Li, Xinzhong; Scott, James; Chen, Yii-Der Ida; Burke, Gregory L.; Kahonen, Mika; Viikari, Jorma; Doering, Angela; Meitinger, Thomas; Davies, Gail; Starr, John M.; Emilsson, Valur; Plump, Andrew; Lindeman, Jan H.; 't Hoen, Peter A. C.; Koenig, Inke R.; Felix, Janine F.; Clarke, Robert; Hopewell, Jemma C.; Ongen, Halit; Breteler, Monique; Debette, Stephanie; DeStefano, Anita L.; Fornage, Myriam; Mitchell, Gary F.; Smith, Nicholas L.; Holm, Hilma; Stefansson, Kari; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Samani, Nilesh J.; Preuss, Michael; Rudan, Igor; Hayward, Caroline; Deary, Ian J.; Wichmann, H-Erich; Raitakari, Olli T.; Palmas, Walter; Kooner, Jaspal S.; Stolk, Ronald P.; Jukema, J. Wouter; Wright, Alan F.; Boomsma, Dorret I.; Bandinelli, Stefania; Gyllensten, Ulf B.; Wilson, James F.; Ferrucci, Luigi; Schmidt, Reinhold; Farrall, Martin; Spector, Tim D.; Palmer, Lyle J.; Tuomilehto, Jaakko; Pfeufer, Arne; Gasparini, Paolo; Siscovick, David; Altshuler, David; Loos, Ruth J. F.; Toniolo, Daniela; Snieder, Harold; Gieger, Christian; Meneton, Pierre; Wareham, Nicholas J.; Oostra, Ben A.; Metspalu, Andres; Launer, Lenore; Rettig, Rainer; Strachan, David P.; Beckmann, Jacques S.; Witteman, Jacqueline C. M.; Erdmann, Jeanette; van Dijk, Ko Willems; Boerwinkle, Eric; Boehnke, Michael; Ridker, Paul M.; Jarvelin, Marjo-Riitta; Chakravarti, Aravinda; Abecasis, Goncalo R.; Gudnason, Vilmundur; Newton-Cheh, Christopher; Levy, Daniel; Munroe, Patricia B.; Psaty, Bruce M.; Caulfield, Mark J.; Rao, Dabeeru C.; Tobin, Martin D.; Elliott, Paul; van Duijn, Cornelia M.

    2011-01-01

    Numerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans(1-3). We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,607), we

  2. Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure

    NARCIS (Netherlands)

    L.V. Wain (Louise); G.C. Verwoert (Germaine); P.F. O'Reilly (Paul); G. Shi (Gang); T. Johnson (Toby); M. Bochud (Murielle); K. Rice (Kenneth); P. Henneman (Peter); A.V. Smith (Albert Vernon); G.B. Ehret (Georg); N. Amin (Najaf); M.G. Larson (Martin); V. Mooser (Vincent); D. Hadley (David); M. Dörr (Marcus); J.C. Bis (Joshua); T. Aspelund (Thor); T. Esko (Tõnu); A.C.J.W. Janssens (Cécile); J.H. Zhao; S.C. Heath (Simon); M. Laan (Maris); J. Fu (Jingyuan); G. Pistis (Giorgio); J. Luan; G. Lucas (Gavin); N. Pirastu (Nicola); I. Pichler (Irene); A.U. Jackson (Anne); R.J. Webster (Rebecca J.); F.F. Zhang; J. Peden (John); R. Schmidt (Reinhold); T. Tanaka (Toshiko); H. Campbell (Harry); W. Igl (Wilmar); Y. Milaneschi (Yuri); J.J. Hottenga (Jouke Jan); V. Vitart (Veronique); D.I. Chasman (Daniel); S. Trompet (Stella); J.L. Bragg-Gresham (Jennifer L.); B.Z. Alizadeh (Behrooz); J.C. Chambers (John); X. Guo (Xiuqing); T. Lehtimäki (Terho); B. Kuhnel (Brigitte); L.M. Lopez; O. Polasek (Ozren); M. Boban (Mladen); C.P. Nelson (Christopher P.); A.C. Morrison (Alanna); V. Pihur (Vasyl); S.K. Ganesh (Santhi); A. Hofman (Albert); S. Kundu (Suman); F.U.S. Mattace Raso (Francesco); F. Rivadeneira Ramirez (Fernando); E.J.G. Sijbrands (Eric); A.G. Uitterlinden (André); S.J. Hwang; R.S. Vasan (Ramachandran Srini); Y.A. Wang (Ying); S.M. Bergmann (Sven); P. Vollenweider (Peter); G. Waeber (Gérard); J. Laitinen (Jaana); A. Pouta (Anneli); P. Zitting (Paavo); W.L. McArdle (Wendy); H.K. Kroemer (Heyo); U. Völker (Uwe); H. Völzke (Henry); N.L. Glazer (Nicole); K.D. Taylor (Kent); T.B. Harris (Tamara); H. Alavere (Helene); T. Haller (Toomas); A. Keis (Aime); M.L. Tammesoo; Y.S. Aulchenko (Yurii); K-T. Khaw (Kay-Tee); P. Galan (Pilar); S. Hercberg (Serge); G.M. Lathrop (Mark); S. Eyheramendy (Susana); E. Org (Elin); S. Sõber (Siim); X. Lu (Xiaowen); I.M. Nolte (Ilja); B.W.J.H. Penninx (Brenda); T. Corre (Tanguy); C. Masciullo (Corrado); C. Sala (Cinzia); L. Groop (Leif); B.F. Voight (Benjamin); O. Melander (Olle); C.J. O'Donnell (Christopher); V. Salomaa (Veikko); P. d' Adamo (Pio); A. Fabretto (Antonella); F. Faletra (Flavio); S. Ulivi (Shelia); F. Del Greco M (Fabiola); M.F. Facheris (Maurizio); F.S. Collins (Francis); R.N. Bergman (Richard); J.P. Beilby (John); J. Hung (Judy); A.W. Musk (Arthur); M. Mangino (Massimo); S.Y. Shin (So Youn); N. Soranzo (Nicole); H. Watkins (Hugh); A. Goel (Anuj); A. Hamsten (Anders); P. Gider (Pierre); M. Loitfelder (Marisa); M. Zeginigg (Marion); D.G. Hernandez (Dena); S.S. Najjar (Samer); P. Navarro (Pau); S.H. Wild (Sarah); A.M. Corsi (Anna Maria); A. Singleton (Andrew); E.J.C. de Geus (Eco); G.A.H.M. Willemsen (Gonneke); A.N. Parker (Alex); L.M. Rose (Lynda); B.M. Buckley (Brendan M.); D.J. Stott (David. J.); M. Orrù (Marco); M. Uda (Manuela); M.M. van der Klauw (Melanie); X. Li (Xiaohui); J. Scott (James); Y.D.I. Chen (Yii-Der Ida); G.L. Burke (Greg); M. Kähönen (Mika); J. Viikari (Jorma); A. Döring (Angela); T. Meitinger (Thomas); G.S. Davis; J.M. Starr (John); V. Emilsson (Valur); A.S. Plump (Andrew); J.H. Lindeman (Jan H.); P.A.C. 't Hoen (Peter); I.R. König (Inke); J.F. Felix (Janine); R. Clarke; J. Hopewell; H. Ongen (Halit); M.M.B. Breteler (Monique); S. Debette (Stéphanie); A.L. DeStefano (Anita); M. Fornage (Myriam); G.F. Mitchell (Gary); H. Holm (Hilma); K. Stefansson (Kari); G. Thorleifsson (Gudmar); U. Thorsteinsdottir (Unnur); N.J. Samani (Nilesh); M. Preuss (Michael); I. Rudan (Igor); C. Hayward (Caroline); I.J. Deary (Ian); H.E. Wichmann (Heinz Erich); O. Raitakari (Olli); W. Palmas (Walter); J.S. Kooner (Jaspal); R.P. Stolk (Ronald); J.W. Jukema (Jan Wouter); A.F. Wright (Alan); D.I. Boomsma (Dorret); S. Bandinelli (Stefania); U. Gyllensten (Ulf); J.F. Wilson (James); L. Ferrucci (Luigi); M. Farrall (Martin); T.D. Spector (Timothy); L.J. Palmer; J. Tuomilehto (Jaakko); A. Pfeufer (Arne); P. Gasparini (Paolo); D.S. Siscovick (David); D. Altshuler (David); R.J.F. Loos (Ruth); D. Toniolo (Daniela); H. Snieder (Harold); C. Gieger (Christian); P. Meneton (Pierre); N.J. Wareham (Nick); B.A. Oostra (Ben); A. Metspalu (Andres); L.J. Launer (Lenore); R. Rettig (Rainer); D.P. Strachan (David); J.S. Beckmann (Jacques); J.C.M. Witteman (Jacqueline); J.A.P. Willems van Dijk (Ko); E.A. Boerwinkle (Eric); M. Boehnke (Michael); P.M. Ridker (Paul); M.R. Järvelin; A. Chakravarti (Aravinda); J. Erdmann (Jeanette); V. Gudnason (Vilmundur); C. Newton-Cheh (Christopher); D. Levy (Daniel); P. Arora (Pankaj); P. Munroe (Patricia); B.M. Psaty (Bruce); M. Caulfield (Mark); D.C. Rao (Dabeeru C.); P. Elliott (Paul); P. Tikka-Kleemola (Päivi); G.R. Abecasis (Gonçalo); I. Barroso (Inês)

    2011-01-01

    textabstractNumerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,60

  3. Central arterial pressure assessment with intensity POF sensor

    Science.gov (United States)

    Leitão, Cátia; Gonçalves, Steve; Antunes, Paulo; Bastos, José M.; Pinto, João. L.; André, Paulo

    2015-09-01

    The central pressure monitoring is considered a new key factor in hypertension assessment and cardiovascular prevention. In this work, it is presented the central arterial systolic pressure assessment with an intensity based POF sensor. The device was tested in four subjects, and stable pulse waves were obtained, allowing the calculation of the central pressure for all the subjects. The results shown that the sensor performs reliably, being a simple and low-cost solution to the intended application.

  4. A pitfall in the measurement of arterial blood pressure in the ischaemic limb during elevation

    DEFF Research Database (Denmark)

    Bülow, J; Jelnes, Rolf

    1987-01-01

    kept at 10 mmHg during elevation. In these patients, the increase in vascular resistance was significantly less compared with the situation in which venous pressure was 0 mmHg during elevation. The arterial pressure still did not decrease. It is concluded that perfusion pressure in the ischaemic lower......In order to evaluate if elevation of the ischaemic limb above heart level is an alternative to the conventionally applied method with external counterpressure for estimation of skin perfusion pressure, femoral and popliteal artery pressures were measured directly in eight patients with occlusion...... of the superficial femoral artery. The measurements were done in the horizontal position and during elevation of the calf above heart level. During elevation relative blood flow, measured by arterio-venous oxygen saturation differences, decreased compared with the horizontal position. In contrast the popliteal...

  5. Implantable blood pressure sensor for analyzing elasticity in arteries

    Science.gov (United States)

    Franco-Ayala, Marco; Martínez-Piñón, Fernando; Reyes-Barranca, Alfredo; Sánchez de la Peña, Salvador; Álvarez-Chavez, José A.

    2009-03-01

    MEMS technology could be an option for the development of a pressure sensor which allows the monitoring of several electronic signals in humans. In this work, a comparison is made between the typical elasticity curves of several arteries in the human body and the elasticity obtained for MEMS silicon microstructures such as membranes and cantilevers employing Finite Element analysis tools. The purpose is to identify which types of microstructures are mechanically compatible with human arteries. The goal is to integrate a blood pressure sensor which can be implanted in proximity with an artery. The expected benefits for this type of sensor are mainly to reduce the problems associated with the use of bulk devices through the day and during several days. Such a sensor could give precise blood pressure readings in a continuous or periodic form, i.e. information that is especially important for some critical cases of hypertension patients.

  6. Noninvasive 24-hour ambulatory arterial blood pressure monitoring in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Wiinberg, N; Henriksen, Jens Henrik

    1995-01-01

    Cirrhotic patients have disturbed systemic hemodynamics with reduced arterial blood pressure, but this has not been investigated during daily activity and sleep. Systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP), and heart rate (HR) were measured by an automatic ambulant...... device for monitoring blood pressure in 35 patients with cirrhosis and 35 healthy matched controls. During the daytime, SBP, DBP, and MAP were significantly lower in the patients than in the controls (median 118 vs. 127; 70 vs. 78; 86 vs. 94 mm Hg, P blood pressures...... were almost similar in the two groups (108 vs. 110; 65 vs. 67; 78 vs. 82 mm Hg, NS). Conversely, HR was significantly higher in the patients both in the daytime (86 vs. 72/min, P blood pressure and HR from daytime...

  7. Noninvasive 24-hour ambulatory arterial blood pressure monitoring in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Wiinberg, N; Henriksen, Jens Henrik

    1995-01-01

    were almost similar in the two groups (108 vs. 110; 65 vs. 67; 78 vs. 82 mm Hg, NS). Conversely, HR was significantly higher in the patients both in the daytime (86 vs. 72/min, P pressure and HR from daytime......Cirrhotic patients have disturbed systemic hemodynamics with reduced arterial blood pressure, but this has not been investigated during daily activity and sleep. Systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP), and heart rate (HR) were measured by an automatic ambulant...... device for monitoring blood pressure in 35 patients with cirrhosis and 35 healthy matched controls. During the daytime, SBP, DBP, and MAP were significantly lower in the patients than in the controls (median 118 vs. 127; 70 vs. 78; 86 vs. 94 mm Hg, P pressures...

  8. Arterial dysfunction but maintained systemic blood pressure in cavin-1-deficient mice.

    Directory of Open Access Journals (Sweden)

    Karl Swärd

    Full Text Available Caveolae are omega-shaped plasma membrane micro-domains that are abundant in cells of the vascular system. Formation of caveolae depends on caveolin-1 and cavin-1 and lack of either protein leads to loss of caveolae. Mice with caveolin-1 deficiency have dysfunctional blood vessels, but whether absence of cavin-1 similarly leads to vascular dysfunction is not known. Here we addressed this hypothesis using small mesenteric arteries from cavin-1-deficient mice. Cavin-1-reporter staining was intense in mesenteric arteries, brain arterioles and elsewhere in the vascular system, with positive staining of both endothelial and smooth muscle cells. Arterial expression of cavin-1, -2 and -3 was reduced in knockout (KO arteries as was expression of caveolin-1, -2 and -3. Caveolae were absent in the endothelial and smooth muscle layers of small mesenteric arteries as determined by electron microscopy. Arginase, a negative regulator of nitric oxide production, was elevated in cavin-1 deficient arteries as was contraction in response to the α1-adrenergic agonist cirazoline. Detailed assessment of vascular dimensions revealed increased media thickness and reduced distensibility, arguing that enhanced contraction was due to increased muscle mass. Contrasting with increased α1-adrenergic contraction, myogenic tone was essentially absent and this appeared to be due in part to increased nitric oxide production. Vasomotion was less frequent in the knock-out vessels. In keeping with the opposing influences on arterial resistance of increased agonist-induced contractility and reduced myogenic tone, arterial blood pressure was unchanged in vivo. We conclude that deficiency of cavin-1 affects the function of small arteries, but that opposing influences on arterial resistance balance each other such that systemic blood pressure in unstressed mice is well maintained.

  9. Magnetic sensor for arterial distension and blood pressure monitoring.

    Science.gov (United States)

    Ruhhammer, Johannes; Herbstritt, Tamara; Ruh, Dominic; Foerster, Katharina; Heilmann, Claudia; Beyersdorf, Friedhelm; Goldschmidtboeing, Frank; Seifert, Andreas; Woias, Peter

    2014-12-01

    A novel sensor for measuring arterial distension, pulse and pressure waveform is developed and evaluated. The system consists of a magnetic sensor which is applied and fixed to arterial vessels without any blood vessel constriction, hence avoiding stenosis. The measurement principle could be validated by in vitro experiments on silicone tubes, and by in vivo experiments in an animal model, thereby indicating the non-linear viscoelastic characteristics of real blood vessels. The sensor is capable to provide absolute measurements of the dynamically varying arterial diameter. By calibrating the sensor, a long-term monitoring system for continuously measuring blood pressure and other cardiovascular parameters could be developed based on the method described. This will improve diagnostics for high risk patients and enable a better, specific treatment.

  10. Sex Differences in Peripheral Augmentation Index and Arterial Reservoir Pressure during Upper Limb Postural Shifts

    Directory of Open Access Journals (Sweden)

    Kevin S. Heffernan

    2014-01-01

    Full Text Available We examined the peripheral hemodynamic response to passive arm postural changes in young men and women. Radial artery pulse waveforms were captured using applanation tonometry in 20 men (age 27 ± 2 yrs, BMI 25 ± 1 kg/m2 and 20 women (age 27 ± 2 yrs, BMI 23±1 kg/m2. Arm position was maintained at either heart level or supported 14 cm above/below heart level in a randomized fashion. Systolic augmentation index (sAIx and diastolic augmentation index (dAIx were used as estimates of pressure from wave reflections arriving in systole and diastole, respectively. A novel reservoir-wave separation technique was used to obtain arterial reservoir pressure (pressure generated by arterial capacitance. Women showed a significant reduction in radial diastolic pressure-time integral (DPTI (P0.05 or dAIx (P>0.05 when moving the arm from below to above heart level. Conversely, men showed an attenuated change in radial DPTI (P>0.05 concomitant with significant increases in reservoir pressure (P<0.05, sAIx (P<0.05, and dAIx (P<0.05. Gravity-mediated changes in regional hemodynamics produced by passive arm postural shifts are sex specific. Men demonstrate less change in regional diastolic pressure concomitant with increased augmentation index and arterial reservoir pressure.

  11. An Electrical Muscle Stimulation Suit for Increasing Blood Pressure

    Science.gov (United States)

    2008-09-01

    being painful . The arterial blood pressure increases from baseline were reg- istered with noninvasive Portapres® equipment (FMS, Amsterdam, The...thighs and over the gluteal and abdominal muscles to create a positive and negative pole over the muscle areas. For better electrical contact... pain . Each subject was instructed to have the investigator lower the intensity or stop the stimulation if muscle contraction pain was experienced

  12. Peripheral arterial blood pressure monitoring adequately tracks central arterial blood pressure in critically ill patients: an observational study

    OpenAIRE

    Mignini, Mariano Alejandro; Piacentini, Enrique; Dubin,Arnaldo

    2006-01-01

    Introduction Invasive arterial blood pressure monitoring is a common practice in intensive care units (ICUs). Accuracy of invasive blood pressure monitoring is crucial in evaluating the cardiocirculatory system and adjusting drug therapy for hemodynamic support. However, the best site for catheter insertion is controversial. Lack of definitive information in critically ill patients makes it difficult to establish guidelines for daily practice in intensive care. We hypothesize that peripheral ...

  13. Skin autofluorescence is increased in patients with carotid artery stenosis and peripheral artery disease.

    Science.gov (United States)

    Noordzij, Marjon J; Lefrandt, Joop D; Loeffen, Erik A H; Saleem, Ben R; Meerwaldt, Robbert; Lutgers, Helen L; Smit, Andries J; Zeebregts, Clark J

    2012-02-01

    Advanced glycation end products (AGEs) have a pivotal role in atherosclerosis. We evaluated skin autofluorescence (SAF), a non-invasive measurement of tissue AGE accumulation, in patients with carotid artery stenosis with and without coexisting peripheral artery occlusive disease (PAOD). SAF was measured using the AGE Reader™ in 56 patients with carotid artery stenosis and in 56 age- and sex-matched healthy controls without diabetes, renal dysfunction or known atherosclerotic disease. SAF was higher in patients with carotid artery stenosis compared to the control group: mean 2.81 versus 2.46 (P = 0.002), but especially in the younger age group of 50-60 years old: mean 2.82 versus 1.94 (P = 0.000). Patients with carotid artery stenosis and PAOD proved to have an even higher SAF than patients with carotid artery stenosis only: mean 3.28 versus 2.66 (P = 0.003). Backward linear regression analysis showed that age, smoking, diabetes mellitus, renal function and the presence of PAOD were the determinants of SAF, but carotid artery stenosis was not. SAF is increased in patients with carotid artery stenosis and PAOD. The univariate and multivariate associations of SAF with age, smoking, diabetes, renal insufficiency and PAOD suggest that increased SAF can be seen as an indicator of widespread atherosclerosis.

  14. Vasodilation increases pulse pressure variation, mimicking hypovolemic status in rabbits

    Directory of Open Access Journals (Sweden)

    Glauco A Westphal

    2010-01-01

    Full Text Available OBJECTIVE: To test the hypothesis that pulse pressure respiratory variation (PPV amplification, observed in hypovolemia, can also be observed during sodium nitroprusside (SNP-induced vasodilation. INTRODUCTION: PPV is largely used for early identification of cardiac responsiveness, especially when hypovolemia is suspected. PPV results from respiratory variation in transpulmonary blood flow and reflects the left ventricular preload variations during respiratory cycles. Any factor that decreases left ventricular preload can be associated with PPV amplification, as seen in hypovolemia. METHODS: Ten anesthetized and mechanically ventilated rabbits underwent progressive hypotension by either controlled hemorrhage (Group 1 or intravenous SNP infusion (Group 2. Animals in Group 1 (n = 5 had graded hemorrhage induced at 10% steps until 50% of the total volume was bled. Mean arterial pressure (MAP steps were registered and assumed as pressure targets to be reached in Group 2. Group 2 (n = 5 was subjected to a progressive SNP infusion to reach similar pressure targets as those defined in Group 1. Heart rate (HR, systolic pressure variation (SPV and PPV were measured at each MAP step, and the values were compared between the groups. RESULTS: SPV and PPV were similar between the experimental models in all steps (p > 0.16. SPV increased earlier in Group 2. CONCLUSION: Both pharmacologic vasodilation and graded hemorrhage induced PPV amplification similar to that observed in hypovolemia, reinforcing the idea that amplified arterial pressure variation does not necessarily represent hypovolemic status but rather potential cardiovascular responsiveness to fluid infusion.

  15. Atrial distension, arterial pulsation, and vasopressin release during negative pressure breathing in humans

    DEFF Research Database (Denmark)

    Pump, B; Damgaard, M; Gabrielsen, A;

    2001-01-01

    During an antiorthostatic posture change, left atrial (LA) diameter and arterial pulse pressure (PP) increase, and plasma arginine vasopressin (AVP) is suppressed. By comparing the effects of a 15-min posture change from seated to supine with those of 15-min seated negative pressure breathing...... in eight healthy males, we tested the hypothesis that with similar increases in LA diameter, suppression of AVP release is dependent on the degree of increase in PP. LA diameter increased similarly during the posture change and negative pressure breathing (-9 to -24 mmHg) from between 30 and 31 +/- 1 to 34...... +/- 1 mm (P breathing from 36 +/- 3 to 42 +/- 3 mmHg (P

  16. Systolic Pressure in Different Percents of Stenosis at Major Arteries

    CERN Document Server

    Mirzaee, Mohammad Reza; Firoozabadi, Bahar; Dandaneband, Meitham

    2016-01-01

    - Modeling Human cardiovascular system is always an important issue. One of the most effective methods is using lumped model to reach to a complete model of human cardiovascular system. Such modeling with advanced considerations is used in this paper. Some of these considerations are as follow: Exact simulating of ventricles as pressure suppliers, peristaltic motion of descending arteries as additional suppliers, and dividing each vessel into more than one compartment to reach more accurate answers. Finally a circuit with more than 150 RLC segments and different elements is made. Then the verification of our complex circuit is done and at the end, obstruction as an important abnormality is investigated. For this aim different percents of obstruction in vital arteries are considered and the results are brought as different graphs at the end. According to physiological texts the citation of our simulation and its results are obvious. To earn productive information about arteries characteristics a 36-vessels mod...

  17. Paradoxical centrally increased diffusivity in perinatal arterial ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Stence, Nicholas V.; Mirsky, David M.; Deoni, Sean C.L. [University of Colorado Anschutz School of Medicine, Department of Radiology, Aurora, CO (United States); Children' s Hospital Colorado, Department of Radiology, Aurora, CO (United States); Armstrong-Wells, Jennifer [University of Colorado Anschutz School of Medicine, Department of Pediatrics (Neurology) and OB/GYN, Aurora, CO (United States); University of Colorado Hemophilia and Thrombosis Center, Aurora, CO (United States)

    2016-01-15

    Restricted diffusion on acute MRI is the diagnostic standard for perinatal arterial ischemic stroke. In a subset of children with perinatal arterial ischemic stroke, primarily those with large infarct volumes, we noted a core of centrally increased diffusivity with a periphery of restricted diffusion. Given the paradoxical diffusion-weighted imaging (DWI) appearance observed in some children with perinatal arterial ischemic stroke, we sought to determine its significance and hypothesized that: (1) centrally increased diffusivity is associated with larger infarcts in perinatal arterial ischemic stroke and (2) this tissue is irreversibly injured (infarcted). We reviewed all perinatal arterial ischemic stroke cases in a prospective cohort study from Aug. 1, 2000, to Jan. 1, 2012. Infarct volumes were measured by drawing regions of interest around the periphery of the area of restricted diffusion on DWI. The Mann-Whitney U test was used to compare means between groups. Of 25 eligible cases, centrally increased diffusivity was seen in 4 (16%). Cases with centrally increased diffusivity had larger average infarct volumes (mean 117,182 mm{sup 3} vs. 36,995 mm{sup 3}; P = 0.008), higher average apparent diffusion coefficient (ADC) values in the infarct core (1,679 x 10{sup -6} mm{sup 2}/s vs. 611 x 10{sup -6} mm{sup 2}/s, P < 0.0001), and higher ADC ratio (1.2 vs. 0.5, P < 0.0001). At last clinical follow-up, children with perinatal arterial ischemic stroke and centrally increased diffusivity were more often treated for ongoing seizures (75% vs. 0%; P < 0.001) than those without. Centrally increased diffusivity was associated with larger stroke volume and the involved tissue was confirmed to be infarcted on follow-up imaging. Radiologists should be aware of this unusual appearance of perinatal arterial ischemic stroke in order to avoid underestimating infarct volume or making an incorrect early diagnosis. (orig.)

  18. Blood pressure and arterial stiffness in obese children and adolescents.

    Science.gov (United States)

    Hvidt, Kristian Nebelin

    2015-03-01

    Obesity, elevated blood pressure (BP) and arterial stiffness are risk factors for cardiovascular disease. A strong relationship exists between obesity and elevated BP in both children and adults. Obesity and elevated BP in childhood track into adult life increasing the risk of cardiovascular disease in adulthood. Ambulatory BP is the most precise measure to evaluate the BP burden, whereas carotid-femoral pulse wave velocity (cfPWV) is regarded as the gold standard for evaluating arterial (i.e. aortic) stiffness. These measures might contribute to a better understanding of obesity's adverse impact on the cardiovascular system, and ultimately a better prevention and treatment of childhood obesity. The overall aim of the present PhD thesis is to investigate arterial stiffness and 24-hour BP in obese children and adolescents, and evaluate whether these measures are influenced by weight reduction. The present PhD thesis is based on four scientific papers.  In a cross-sectional design, 104 severe obese children and adolescents with an age of 10-18 years were recruited when newly referred to the Children's Obesity Clinic, Holbæk University Hospital, and compared to 50 normal weighted age and gender matched control individuals. Ambulatory BP was measured, and cfPWV was investigated in two ways in respect to the distance measure of aorta; the previously recommended length - the so called subtracted distance, and the currently recommended length - the direct distance. In a longitudinal design, the obese patients were re-investigated after one-year of lifestyle intervention at the Children's Obesity Clinic in purpose of reducing the degree of obesity. In the cross-sectional design, the obese group had higher measures of obesity, while matched for age, gender and height, when compared to the control group. In the longitudinal design, 74% of the 72 followed up obese patients experienced a significant weight reduction. CfPWV was dependent on the method used to measure the

  19. Post-Weaning Protein Malnutrition Increases Blood Pressure and Induces Endothelial Dysfunctions in Rats

    OpenAIRE

    Aucelia C S de Belchior; Angeli, Jhuli K.; Thaís de O Faria; Siman, Fabiana D. M.; Edna A Silveira; Eduardo F Meira; da Costa, Carlos P.; Dalton V Vassallo; Alessandra S Padilha

    2012-01-01

    Malnutrition during critical periods in early life may increase the subsequent risk of hypertension and metabolic diseases in adulthood, but the underlying mechanisms are still unclear. We aimed to evaluate the effects of post-weaning protein malnutrition on blood pressure and vascular reactivity in aortic rings (conductance artery) and isolated-perfused tail arteries (resistance artery) from control (fed with Labina®) and post-weaning protein malnutrition rats (offspring that received a diet...

  20. The pulmonary vasculature in a neonatal porcine model with increased pulmonary blood flow and pressure

    DEFF Research Database (Denmark)

    Stenbøg, Elisabeth Vidstid; Steinbruchel, Daniel Andreas; Thomsen, Anne Bloch

    2001-01-01

    . By three months of age, nearly all shunts had closed spontaneously, and haemodynamics were normal. Ligation of the left pulmonary artery resulted in a normal total pulmonary blood flow, despite only the right lung being perfused, and a 33% increase in systolic pulmonary arterial pressure...... included sham operations in 13, or no operations in 10 pigs. Follow-up was continued for three months. The interventions were compatible with survival in most pigs. The shunts resulted in an acute 85% increase in systolic pulmonary arterial pressure, and a more than twofold increase in pulmonary blood flow...

  1. Arterial pulse pressure amplification described by means of a nonlinear wave model: characterization of human aging

    Science.gov (United States)

    Alfonso, M.; Cymberknop, L.; Armentano, R.; Pessana, F.; Wray, S.; Legnani, W.

    2016-04-01

    The representation of blood pressure pulse as a combination of solitons captures many of the phenomena observed during its propagation along the systemic circulation. The aim of this work is to analyze the applicability of a compartmental model for propagation regarding the pressure pulse amplification associated with arterial aging. The model was applied to blood pressure waveforms that were synthesized using solitons, and then validated by waveforms obtained from individuals from differentiated age groups. Morphological changes were verified in the blood pressure waveform as a consequence of the aging process (i.e. due to the increase in arterial stiffness). These changes are the result of both a nonlinear interaction and the phenomena present in the propagation of nonlinear mechanic waves.

  2. Arterial Clamping Increases Central Renal Cryoablation Efficacy: An Animal Study

    DEFF Research Database (Denmark)

    Nonboe, Lasse Larsen; Nielsen, Tommy Kjaergaard; Høyer, Søren;

    2017-01-01

    INTRODUCTION: The minimally invasive treatment of small renal masses with cryoablation has become increasingly widespread during the past 15 years. Studies with long-term follow-up are beginning to emerge, showing good oncological control, however, tumors with a central and endophytic location seem...... to possess an increased risk of treatment failure. Such tumors are likely to be subjected to a high volume of blood giving thermal protection to the cancerous cells. Arterial clamping during freezing might reduce this effect but at the same time subject the kidney to ischemia. The aim of this study...... was to evaluate the effect of renal artery clamping during cryoablation in a porcine survival model. METHODS: Ten Danish Landrace pigs (approximately 40 kg) underwent bilateral laparoscopic cryoablation with clamping of the right renal artery during freezing. The cryoablation consisted of a standard double...

  3. Redox signaling via oxidative inactivation of PTEN modulates pressure-dependent myogenic tone in rat middle cerebral arteries.

    Directory of Open Access Journals (Sweden)

    Debebe Gebremedhin

    Full Text Available The present study examined the level of generation of reactive oxygen species (ROS and roles of inactivation of the phosphatase PTEN and the PI3K/Akt signaling pathway in response to an increase in intramural pressure-induced myogenic cerebral arterial constriction. Step increases in intraluminal pressure of cannulated cerebral arteries induced myogenic constriction and concomitant formation of superoxide (O2 (.- and its dismutation product hydrogen peroxide (H2O2 as determined by fluorescent HPLC analysis, microscopic analysis of intensity of dihydroethidium fluorescence and attenuation of pressure-induced myogenic constriction by pretreatment with the ROS scavenger 4,hydroxyl-2,2,6,6-tetramethylpiperidine1-oxyl (tempol or Mito-tempol or MitoQ in the presence or absence of PEG-catalase. An increase in intraluminal pressure induced oxidation of PTEN and activation of Akt. Pharmacological inhibition of endogenous PTEN activity potentiated pressure-dependent myogenic constriction and caused a reduction in NPo of a 238 pS arterial KCa channel current and an increase in [Ca(2+]i level in freshly isolated cerebral arterial muscle cells (CAMCs, responses that were attenuated by Inhibition of the PI3K/Akt pathway. These findings demonstrate an increase in intraluminal pressure induced increase in ROS production triggered redox-sensitive signaling mechanism emanating from the cross-talk between oxidative inactivation of PTEN and activation of the PI3K/Akt signaling pathway that involves in the regulation of pressure-dependent myogenic cerebral arterial constriction.

  4. Non-invasive quantification of peripheral arterial volume distensibility and its non-linear relationship with arterial pressure.

    Science.gov (United States)

    Zheng, Dingchang; Murray, Alan

    2009-05-29

    Arterial wall function is associated with different physiological and clinical factors. Changes in arterial pressure cause major changes in the arterial wall. This study presents a simple non-invasive method to quantify arterial volume distensibility changes with different arterial pressures. The electrocardiogram, finger and ear photoplethysmogram were recorded from 15 subjects with the right arm at five different positions (90 degrees , 45 degrees , 0 degrees , -45 degrees and -90 degrees referred to the horizontal level). Arm pulse propagation time was determined by subtracting ear pulse transit time from finger pulse transit time, and was used to obtain arterial volume distensibility. The mean arterial blood pressure with the arm at the horizontal level was acquired, and changes with position were calculated using the hydrostatic principle that blood pressure in the arm is linearly related to its vertical distance from the horizontal level. The mean arm pulse propagation times for the five different positions were 88, 72, 57, 54 and 52ms, with the corresponding mean arterial volume distensibility of 0.234%, 0.158%, 0.099%, 0.088% and 0.083% per mmHg. For all consecutive changes in arm position, arm pulse propagation time and arterial volume distensibility, were significantly different (all probability Ppressure decreased significantly between each consecutive arm position from 90 degrees to -45 degrees (all Ppressure changes from 101 to 58mmHg. In conclusion, the inverse and non-linear relationship between arterial volume distensibility and arterial pressure has been quantified using a simple arm positioning procedure, with the greatest effect at low pressures. This work is an important step in developing a simple non-invasive technique for assessing peripheral arterial volume distensibility.

  5. Relationship of daily arterial blood pressure monitoring readings and arterial stiffness profile in male patients with chronic obstructive pulmonary disease combined with arterial hypertension

    Directory of Open Access Journals (Sweden)

    Karoli N.A.

    2013-06-01

    Full Text Available The aim of the study was to determine correlation between arterial blood pressure daily rhythm and daily profile of arterial stiffness in male patients with chronic obstructive pulmonary disease (COPD and arterial hypertension. Materials et methods: Prospective investigation comprised 45 male patients with COPD and arterial hypertension. Individuals of 40 years younger and 80 years elder, patients with diabetes, stroke, angina pectoris, or heart infarction, vascular diseases, and exacerbation of chronic disease, bronchial and pulmonary diseases of other etiology were excluded from the analyses. Comparison group included 47 patients with essential arterial hypertension and without chronic respiratory diseases closely similar on general parameters with patients from main clinical series. Twenty-four-hour arterial blood pressure monitoring (ABPM and daily arterial stiffness monitoring were performed using BPLab® MnSDP-2 apparatus (Petr Telegin, Russian Federation. Results: Patients with COPD combined with arterial hypertension with raised arterial stiffness measures prevail over individuals in essential hypertension group. There is pathological alteration of the ABPM circadian rhythm and raised «Pressure load» values in raised arterial stiffness group. Conclusion: We found ABPM raised parameters in patients with COPD and arterial hypertension. It confirms necessity of ABPM in daily arterial stiffness assessment in patients with COPD.

  6. Roles of Arterial Stiffness and Blood Pressure in Hypertension-Associated Cognitive Decline in Healthy Adults.

    Science.gov (United States)

    Hajjar, Ihab; Goldstein, Felicia C; Martin, Greg S; Quyyumi, Arshed A

    2016-01-01

    Although there is strong evidence that hypertension leads to cognitive decline, especially in the executive domain, the relationship between blood pressure and cognition has been conflicted. Hypertension is characterized by blood pressure elevation and increased arterial stiffness. We aimed at investigating whether arterial stiffness would be superior to blood pressure in predicting cognitive decline and explaining the hypertension-executive decline association. A randomly selected asymptomatic population (n=591, age=49.2 years, 70% women, 27% black, and education=18 years) underwent annual vascular and cognitive assessments. Cognition was assessed using computerized versions commonly used cognitive tests, and principal component analysis was used for deriving cognitive scores for executive function, memory, and working memory. Arterial stiffness was measured by carotid-femoral pulse wave velocity (PWV). Higher PWV, but not blood pressure, was associated with a steeper decline in executive (P=0.0002), memory (P=0.05), and working memory (P=0.02) scores after adjusting for demographics, education, and baseline cognitive performance. This remained true after adjusting for hypertension. Hypertension was associated with greater decline in executive score (P=0.0029) and those with combined hypertension and elevated PWV (>7 m/s) had the greatest decline in executive score (P value hypertension×PWV=0.02). PWV explained the association between hypertension and executive function (P value for hypertension=0.0029 versus 0.24 when adjusting for PWV). In healthy adults, increased arterial stiffness is superior to blood pressure in predicting cognitive decline in all domains and in explaining the hypertension-executive function association. Arterial stiffness, especially in hypertension, may be a target in the prevention of cognitive decline.

  7. A Neural Network for Estimation of Aortic Pressure from the Radial Artery Pressure Pulse

    Science.gov (United States)

    2001-10-25

    from periphery to artery: a model based study, American Journal of Physiology, 1998,274:43, pp H1386-92 [9] C. Chen, E. Nevo , B Fetics, P Pak, F, Yin, L...36. [10] B Fetics, E Nevo , C. Chen, D Kass, Parametric model derivation of transfer function for noninvasive estimation of aortic pressure by radial

  8. Acute nitric oxide synthase inhibition and endothelin-1-dependent arterial pressure elevation

    Directory of Open Access Journals (Sweden)

    Robert eRapoport

    2014-04-01

    Full Text Available Key evidence that endogenous nitric oxide (NO inhibits the continuous, endothelin (ET-1-mediated drive to elevate arterial pressure includes demonstrations that ET-1 mediates a significant component of the pressure elevated by acute exposure to NO synthase (NOS inhibitors. This review examines the characteristics of this pressure elevation in order to elucidate potential mechanisms associated with the negative regulation of ET-1 by NO and, thereby, provide potential insight into the vascular pathophysiology underlying NO dysregulation. We surmise that the magnitude of the ET-1-dependent component of the NOS inhibitor-elevated pressure is 1 independent of underlying arterial pressure and other pressor pathways activated by the NOS inhibitors and 2 dependent on relatively higher NOS inhibitor dose, release of stored and de novo synthesized ET-1, and ETA receptor-mediated increased vascular resistance. Major implications of these conclusions include: 1 the marked variation of the ET-1-dependent component, i.e., from 0-100% of the pressure elevation, reflects the NO-ET-1 regulatory pathway. Thus, NOS inhibitor-mediated, ET-1-dependent pressure elevation in vascular pathophysiologies is an indicator of the level of compromised/enhanced function of this pathway; 2 NO is a more potent inhibitor of ET-1-mediated elevated arterial pressure than other pressor pathways, due in part to inhibition of intravascular pressure-independent release of ET-1. Thus, the ET-1-dependent component of pressure elevation in vascular pathophysiologies associated with NO dysregulation is of greater magnitude at higher levels of compromised NO.

  9. Arterial blood-pressure change and endogenous circulating substance P in man

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Kastrup, J; Schaffalitzky De Muckadell, O B

    1985-01-01

    Substance P (SP) is a powerful vasodilator and this peptide is today considered to be a chemical messenger. The potential effects on circulating SP of acute changes in arterial blood-pressure was investigated in nine subjects. An increase in arterial mean blood-pressure (+33%, P less than 0.001, n...... = 9) was obtained by infusion of angiotensin II and a decrease in pressure (-10%, P less than 0.005, n = 6) was obtained by ganglionic blockade. The concentration of SP in plasma, from supine subjects in the normotensive condition, ranged from 3 to 13 pmol/l (with a mean of 5.6 pmol/l). SP was thus...

  10. Microalbuminuria associated with systolic blood pressure and arterial compliance in Chinese metabolic syndrome patients

    Institute of Scientific and Technical Information of China (English)

    LI Xin-li; XU Qiong; TONG Min; LU Xin-zheng; ZHANG Hai-feng; ZHOU Yan-li; CAO Ke-jiang; HUANG Jun

    2007-01-01

    Background There is significant evidence showing that microalbuminuria and arterial compliance are sensitive markers for early cardiovascular diseases. However, whether microalbuminuria is associated with reduced arterial compliance in Chinese metabolic syndrome (MS) patients remains unknown.Methods According to the definition of MS proposed by ATPⅢ in 2001, USA, subjects (n=362) were divided into three groups according to the number of risk factors: group 1 (control), group 2 (medium, < 3 risk factors) and group 3 (MS, ≥ 3 risk factors). Both large artery compliance (C1) and small artery compliance (C2) were measured with the CVProfilor DO-2020 Cardiovascular Profiling System, and microalbuminuria was evaluated with the ratio of albumin to urine creatinine.Results (1) As C1 and C2 levels elasticity decreased, albumin creatinine ratio (ACR) and the prevalence of microalbuminuria increased within those groups with MS risk factors. C1 and C2 were negatively correlated with the ranking of MS risk factors, ACR was positively correlated with the ranking of MS risk factors (all P<0.05). (2) Subjects were also categorized into a microalbuminuria group and a normal group, C1 and C2 in the microalbuminuria group were lower than in the normal group. (3) Multivariate regression analysis showed that increased systolic blood pressure (SBP) and reduced arterial compliance were the main risk factors for microalbuminuria in the MS group.Conclusions The risk of developing microalbuminuria was higher in the subjects with multiple metabolic abnormalities.Increased systolic blood pressure and reduced arterial compliance may be the main predictors for microalbuminuria in MS.

  11. [Large artery wall properties in dialyse and renal transplant patients with normal blood pressure].

    Science.gov (United States)

    Posadzy-Małaczyńska, Anna; Kosch, Marcus; Hausberg, Martin; Rahn, Karl H; Małaczyński, Paweł; Głuszek, Jerzy; Tykarski, Andrzej

    2004-01-01

    Structural and mechanical properties of the arterial wall are altered in patients with renal failure. Age and hypertension are known to affect the vessel wall structure. Aging process of arterial wall appears to be accelerated in patients with end-stage renal failure. The mechanisms responsible for reduced arterial compliance and distensibility in dialyse patients and renal transplant recipients without hypertension remain to be evaluated. 20 normotensive dialyse patients (D), 20 normotensive renal transplant recipients (T) and 20 healthy volunteers (N) matched for age, sex and blood pressure as controls were enrolled in to the study. Patients with cardiovascular risk factors and diabetes were excluded. The arterial blood pressure of all patients placed below 140/90 mmHg. The dialyse patients and renal transplant recipients were eligible for the study if the serum creatinine level was below 2 mg/dl. In all subjects, fasting concentrations of serum creatinine, total cholesterol, HDL-cholesterol, LDL-cholesterol, hemoglobin and glucose were determined at enrollment to the study. Long-term immunosuppression consisted of cyclosporine and prednisolone. Blood pressure was measured using an automatic sphygmomanometer (Criticon Dinamap model 1846 SX). Pulse wave velocity (PWV) was evaluated using non-invasive automatic Complior device. The vessel wall properties of the left common carotid artery were studied using multigate pulsed Doppler's system (Pie Medical Equipment BV Maastricht, The Netherlands). The frequency of transducer used was 7.5 MHz. With this non-invasive method, the end-diastolic diameter (d) and the systolic increase of vessel diameter (distension delta d) were measured using ECG trigger. From these data relative systolic increase of vessel diameter (delta d/d) and arterial wall distensibility coefficient (DC) were calculated. Simultaneously with the ultrasound measurements at the left common carotid artery carotid pulse waveforms are recorded using

  12. Plasma viscosity increase with progression of peripheral arterial atherosclerotic disease.

    Science.gov (United States)

    Poredos, P; Zizek, B

    1996-03-01

    Increased blood and plasma viscosity has been described in patients with coronary and peripheral arterial disease. However, the relation of viscosity to the extent of arterial wall deterioration--the most important determinant of clinical manifestation and prognosis of the disease--is not well known. Therefore, the authors studied plasma viscosity as one of the major determinants of blood viscosity in patients with different stages of arterial disease of lower limbs (according to Fontaine) and its relation to the presence of some risk factors of atherosclerosis. The study encompassed four groups of subjects: 19 healthy volunteers (group A), 18 patients with intermittent claudication up to 200 m (stage II; group B), 15 patients with critical ischemia of lower limbs (stage III and IV; group C), and 16 patients with recanalization procedures on peripheral arteries. Venous blood samples were collected from an antecubital vein without stasis for the determination of plasma viscosity (with a rotational capillary microviscometer, PAAR), fibrinogen, total cholesterol, alpha-2-macroglobulin, and glucose concentrations. In patients with recanalization procedure local plasma viscosity was also determined from blood samples taken from a vein on the dorsum of the foot. Plasma viscosity was most significantly elevated in the patients with critical ischemia (1.78 mPa.sec) and was significantly higher than in the claudicants (1.68 mPa.sec), and the claudicants also had significantly higher viscosity than the controls (1.58 mPa.sec). In patients in whom a recanalization procedure was performed, no differences in systemic and local plasma viscosity were detected, neither before nor after recanalization of the diseased artery. In all groups plasma viscosity was correlated with fibrinogen concentration (r=0.70, P < 0.01) and total cholesterol concentration (r=0.24, P < 0.05), but in group C (critical ischemia) plasma viscosity was most closely linked to the concentration of alpha-2

  13. Adiponectin Genotype, Blood Pressures, and Arterial Stiffness: The Cardiometabolic Risk in Chinese (CRC) Study.

    Science.gov (United States)

    Liang, Jun; Qiu, Qinqin; Gong, Ying; Liu, Xuekui; Dou, Lianjun; Zou, Caiyan; Wang, Yu; Qi, Lu

    2015-05-01

    The authors examined whether the adiponectin gene (ADIPOQ) variant was associated with blood pressure and arterial stiffness in Chinese adults. A genome-wide association study of the adiponectin variant rs864265 in the ADIPOQ gene was genotyped in a total of 2364 participants. After adjustment for sex, age, body mass index (BMI), fasting glucose, and lipids, participants carrying the T allele of rs864265 showed a greater increase in carotid-femoral pulse wave velocity (cfPWV) and systolic blood pressure (SBP). Further adjustment for blood pressure did not appreciably change the association with cfPWV. The authors found significant interactions between rs864265 and BMI, waist circumference, body fat percentage, and SBP in relation to cfPWV (P for interaction = .035, .001, .003, .013, respectively). The T allele of rs864265 was associated with high blood pressure and arterial stiffness. BMI, body fat percentage, waist circumference, and SBP might modify the effects of genetic polymorphism on arterial stiffness.

  14. [Left ventricular relaxation and ambulatory blood pressure in mild, untreated arterial hypertension].

    Science.gov (United States)

    Herpin, D; Raynier, P; Ciber, M; Amiel, A; Boutaud, P; Demange, J

    1989-03-01

    Twenty patients with mild, untreated arterial hypertension had ambulatory blood pressure recordings and a digitized echocardiographic study of the left ventricle with measurement of its mass (LVM) and of relaxation parameters. A significant correlation was found between LVM and ambulatory systolic pressure during daytime (r = 0.64; p less than 0.01; n = 20) and during 24 hours (r = 0.79; p less than 0.001; n = 16). One of the relaxation parameters studied, the time taken to reach maximal speed of left ventricular enlargement, was closely related to the diurnal diastolic blood pressure (r = 0.58; p less than 0.01; n = 20), whereas in this population with mild arterial blood pressure none of the parameters was related to the amount of increase of LVM. One may therefore consider the abnormalities of left ventricular relaxation as likely to appear at an early stage of arterial hypertension; their discovery may antedate that of LVM and confirm that the hypertensive disease is real. However, the methodological problems encountered with type of exploration ought to be stressed: left ventricular relaxation is a multifactorial phenomenon, and its echocardiographic approach is subject to many hazards.

  15. The effects of epinine on arterial blood pressure and regional vascular resistances in anesthetized rats.

    Science.gov (United States)

    Martínez-Mir, I; Palop, V; Morales-Olivas, F J; Estañ, L; Rubio, E

    1998-07-01

    1. We carried out experiments in anesthetized rats to study the hemodynamic effects of intravenous injections of epinine. 2. Epinine (1-320 micrograms/kg) produced a biphasic effect on mean arterial blood pressure (n = 30). At doses lower than 40 micrograms/kg, arterial blood pressure decreased (by as much as 21.5 +/- 3.4%), though at higher doses it increased dose dependently (by as much as 73.2 +/- 14.5%). Epinine also produced bradicardia in a dose-dependent manner (by as much as 26.4 +/- 4.9%). Sulpiride (100 micrograms/kg) suppressed the hypotensive effect of epinine but did not change the hypertensive effect. In the presence of prazosin (1,000 micrograms/kg), arterial blood pressure remained significantly decreased at all doses of epinine. Neither sulpiride nor prazosin changed the bradycardic effect of epinine. 3. Prazosin produced a significant decrease in renal vascular resistance. Epinine (5 micrograms/kg) after prazosin reverted the effects of prazosin in renal vascular resistance, without any significant modification in the renal blood flows. However, 20 micrograms/kg epinine increased the renal vascular resistances and, moreover, produced a significant decrease in the blood flows of both kidneys. Neither prazosin nor epinine produced modifications in the intestinal vascular bed. 4. Although epinine possesses significant dopamine and alpha-adrenergic activities that are involved in the biphasic effect of the agent on mean arterial blood pressure in anesthetized rats, in the presence of prazosin, it is not possible to manifest dopaminergic activity involved in the increase in renal or mesenteric blood flow; this may be due to the low tone of the vascular wall induced by the alpha-adrenergic antagonist, though an alpha 2-activity cannot be discarded.

  16. Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure (letter)

    NARCIS (Netherlands)

    Wain, L.V.; Verwoert, G.C.; O'Reilly, P.F.; Shi, G.; Johnson, T.; Johnson, A.D.; Bochud, M.; Rice, K.M.; Henneman, P.; Smith, A.V.; Ehret, G.B.; Amin, N.; Larson, M.G.; Mooser, V.; Hadley, D.; Dorr, M.; Bis, J.C.; Aspelund, T.; Esko, T.; Janssens, A.C.J.W.; Zhao, J.H.; Heath, S.; Laan, M.; Fu, J.Y.; Pistis, G.; Luan, J.A.; Arora, P.; Lucas, G.; Pirastu, N.; Pichler, I.; Jackson, A.U.; Webster, R.J.; Zhang, F.; Peden, J.F.; Schmidt, H.; Tanaka, T.; Campbell, H.; Igl, W.; Milaneschi, Y.; Hottenga, J.J.; Vitart, V.; Chasman, D.I.; Trompet, S.; Bragg-Gresham, J.L.; Alizadeh, B.Z.; Chambers, J.C.; Guo, X.Q.; Lehtimaki, T.; Kuhnel, B.; Lopez, L.M.; Polasek, O.; Boban, M.; Nelson, C.P.; Morrison, A.C.; Pihur, V.; Ganesh, S.K.; Hofman, A.; Kundu, S.; Mattace-Raso, F.U.S.; Rivadeneira, F.; Sijbrands, E.J.G.; Uitterlinden, A.G.; Hwang, S.J.; Vasan, R.S.; Wang, T.J.; Bergmann, S.; Vollenweider, P.; Waeber, G.; Laitinen, J.; Pouta, A.; Zitting, P.; McArdle, W.L.; Kroemer, H.K.; Volker, U.; Volzke, H.; Glazer, N.L.; Taylor, K.D.; Harris, T.B.; Alavere, H.; Haller, T.; Keis, A.; Tammesoo, M.L.; Aulchenko, Y.; Barroso, I.; Khaw, K.T.; Galan, P.; Hercberg, S.; Lathrop, M.; Eyheramendy, S.; Org, E.; Sober, S.; Lu, X.W.; Nolte, I.M.; Penninx, B.W.; Corre, T.; Masciullo, C.; Sala, C.; Groop, L.; Voight, B.F.; Melander, O.; O'Donnell, C.J.; Salomaa, V.; d'Adamo, A.P.; Fabretto, A.; Faletra, F.; Ulivi, S.; Del Greco, M.F.; Facheris, M.; Collins, F.S.; Bergman, R.N.; Beilby, J.P.; Hung, J.; Musk, A.W.; Mangino, M.; Shin, S.Y.; Soranzo, N.; Watkins, H.; Goel, A.; Hamsten, A.; Gider, P.; Loitfelder, M.; Zeginigg, M.; Hernandez, D.; Najjar, S.S.; Navarro, P.; Wild, S.H.; Corsi, A.M.; Singleton, A.; de Geus, E.J.C.; Willemsen, G.; Parker, A.N.; Rose, L.M.; Buckley, B.; Stott, D.; Orru, M.; Uda, M.; van der Klauw, M.M.; Zhang, W.H.; Li, X.Z.; Scott, J.; Chen, Y.D.I.; Burke, G.L.; Kahonen, M.; Viikari, J.; Doring, A.; Meitinger, T.; Davies, G.; Starr, J.M.; Emilsson, V.; Plump, A.; Lindeman, J.H.; 'T Hoen, P.A.C.; Konig, I.R.; Felix, J.F.; Clarke, R.; Hopewell, J.C.; Ongen, H.; Breteler, M.; Debette, S.; DeStefano, A.L.; Fornage, M.; Mitchell, G.F.; Smith, N.L.; Holm, H.; Stefansson, K.; Thorleifsson, G.; Thorsteinsdottir, U.; Samani, N.J.; Preuss, M.; Rudan, I.; Hayward, C.; Deary, I.J.; Wichmann, H.E.; Raitakari, O.T.; Palmas, W.; Kooner, J.S.; Stolk, R.P.; Jukema, J.W.; Wright, A.F.; Boomsma, D.I.; Bandinelli, S.; Gyllensten, U.B.; Wilson, J.F.; Ferrucci, L.; Schmidt, R.; Farrall, M.; Spector, T.D.; Palmer, L.J.; Tuomilehto, J.; Pfeufer, A.; Gasparini, P.; Siscovick, D.; Altshuler, D.; Loos, R.J.F.; Toniolo, D.; Snieder, H.; Gieger, C.; Meneton, P.; Wareham, N.J.; Oostra, B.A.; Metspalu, A.; Launer, L.; Rettig, R.; Strachan, D.P.; Beckmann, J.S.; Witteman, J.C.M.; Erdmann, J.; van Dijk, K.W.; Boerwinkle, E.; Boehnke, M.; Ridker, P.M.; Jarvelin, M.R.; Chakravarti, A.; Abecasis, G.R.; Gudnason, V.; Newton-Cheh, C.; Levy, D.; Munroe, P.B.; Psaty, B.M.; Caulfield, M.J.; Rao, D.C.; Tobin, M.D.; Elliott, P.; van Duijn, C.M.

    2011-01-01

    Numerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans(1-3). We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,607), we

  17. Arterial compliance in patients with cirrhosis: stroke volume-pulse pressure ratio as simplified index

    DEFF Research Database (Denmark)

    Fuglsang, S; Bendtsen, F; Christensen, E

    2001-01-01

    Arterial function may be altered in patients with cirrhosis. We determined compliance of the arterial tree (C(1)) in relation to systemic and splanchnic hemodynamic derangement and clinical variables. C(1) and the stroke volume-pulse pressure index (SV/PP) were significantly higher (+62% and +40%...... predictors of SV/PP (P abnormalities in the arterial compliance of these patients....

  18. Simulations of piezoelectric pressure sensor for radial artery pulse measurement

    Energy Technology Data Exchange (ETDEWEB)

    Joshi, Abhay B. [Department of Electronic Science, University of Pune, Pune 411 007 (India); Kalange, Ashok E. [Department of Electronic Science, University of Pune, Pune 411 007 (India); Tuljaram Chaturchand College, Baramati 413 102 (India); Bodas, Dhananjay, E-mail: dhananjay.bodas@gmail.co [Center for Nanobio Sciences, Agharkar Research Institute, Pune 411 004 (India); Gangal, S.A. [Department of Electronic Science, University of Pune, Pune 411 007 (India)

    2010-04-15

    A radial artery pulse is used to diagnose human body constitution (Prakruti) in Ayurveda. A system consisting of piezoelectric sensor (22 mm x 12 mm), data acquisition card and LabView software was used to record the pulse data. The pulse obtained from the sensor was noisy, even though signal processing was done. Moreover due to large sized senor accurate measurements were not possible. Hence, a need was felt to develop a sensor of the size of the order of finger tip with a resonant frequency of the order of 1 Hz. A micromachined pressure sensor based on piezoelectric sensing mechanism was designed and simulated using CoventorWare. Simulations were carried out by varying dimensions of the sensor to optimize the resonant frequency, stresses and voltage generated as a function of applied pressure. All simulations were done with pressure ranging of 1-30 kPa, which is the range used by Ayurvedic practitioners for diagnosis. Preliminary work on fabrication of such a sensor was carried out successfully.

  19. Longitudinal perspective on the conundrum of central arterial stiffness, blood pressure, and aging.

    Science.gov (United States)

    Scuteri, Angelo; Morrell, Christopher H; Orrù, Marco; Strait, James B; Tarasov, Kirill V; Ferreli, Liana Anna Pina; Loi, Francesco; Pilia, Maria Grazia; Delitala, Alessandro; Spurgeon, Harold; Najjar, Samer S; AlGhatrif, Majd; Lakatta, Edward G

    2014-12-01

    The age-associated increase in arterial stiffness has long been considered to parallel or to cause the age-associated increase in blood pressure (BP). Yet, the rates at which pulse wave velocity (PWV), a measure of arterial stiffness, and BP trajectories change over time within individuals who differ by age and sex have not been assessed and compared. This study determined the evolution of BP and aortic PWV trajectories during a 9.4-year follow-up in >4000 community-dwelling men and women of 20 to 100 years of age at entry into the SardiNIA Study. Linear mixed effects model analyses revealed that PWV accelerates with time during the observation period, at about the same rate over the entire age range in both men and women. In men, the longitudinal rate at which BP changed over time, however, did not generally parallel that of PWV acceleration: at ages>40 years the rates of change in systolic BP (SBP) and pulse pressure (PP) increase plateaued and then declined so that SBP, itself, also declined at older ages, whereas PP plateaued. In women, SBP, diastolic BP, and mean BP increased at constant rates across all ages, producing an increasing rate of increase in PP. Therefore, increased aortic stiffness is implicated in the age-associated increase in SBP and PP. These findings indicate that PWV is not a surrogate for BP and that arterial properties other than arterial wall stiffness that vary by age and sex also modulate the BP trajectories during aging and lead to the dissociation of PWV, PP, and SBP trajectories in men.

  20. [Acute Postoperative Negative Pressure Pulmonary Edema Caused by the Compression of Brachiocephalic Artery].

    Science.gov (United States)

    Tagawa, Miki; Iwai, Hidetaka; Fukatsu, Ken; Shimada, Mami; Hirabayashi, Yoshihiro

    2016-06-01

    We report a case of negative-pressure pulmonary edema occurring by tracheal obstruction caused by the brachiocephalic artery. The patient had deformed thorax with cerebral palsy, which deformed thorax placing the brachiocephalic artery high over the trachea, resulting in close and tight contact between the artery and trachea. Additional deformity of the thorax associated with myotonic attacks after general anesthesia might shorten the distance between the sternal notch and the vertebral body, resulting in the tracheal obstruction by the artery.

  1. Failure of unilateral carotid artery ligation to affect pressure-induced interruption of rapid axonal transport in primate optic nerves.

    Science.gov (United States)

    Radius, R L; Schwartz, E L; Anderson, D R

    1980-02-01

    Previous experiments showed that optic nerve axonal transport can be blocked at the level of the lamina cribrosa by elevated intraocular pressure. In an effort to discover if this blockage might be secondary to pressure-induced ischemia, we studied the effect of unilateral common carotid artery ligation upont the pressure-induced interruption of axonal transport. In 13 owl monkeys (Aotus trivirgatus), the right common carotid artery was ligated within the anterior cervical triangle. Three days later, ophtalmodynomometry was performed on all experimental eyes. In nine of the 13 animals, this estimate of ophthalmic artery pressure was 10 to 20 mm Hg less in the right compared to the left eye. Optic nerve axonal transport was studied in right and left eyes during 5 hours of increased intraocular pressure (ocular pressure 35 mm Hg less than mean femoral artery blood pressure). No significant difference in the extent to which the transport mechanisms were interrupted could be demonstrated when comparing right and left eyes of the experimental animals. These observations fail to support a vascular mechanism for this pressure-induced interruption of axonal transport.

  2. Noninvasively assessed pulsatility of ascending aortic pressure waveform is associated with the presence of coronary artery narrowing.

    Science.gov (United States)

    Wykretowicz, Andrzej; Metzler, Lidia; Milewska, Agata; Balinski, Marek; Rutkowska, Agnieszka; Adamska, Karolina; Krauze, Tomasz; Guzik, Przemysław; Dziarmaga, Mieczysław; Wysocki, Henryk

    2008-01-01

    Several hemodynamic indices, measured invasively in the ascending aorta during routine angiography, are related to the presence and severity of coronary atherosclerosis. Radial artery tonometry, when combined with a validated transfer function, offers the possibility of noninvasive assessment of central arterial pressure. We aim to evaluate the association between noninvasive indices of aortic or radial pressure waveforms and the presence of a significant coronary stenosis. Patients who underwent elective coronary angiography were studied (110 men, 91 women, mean age 53 +/- 0.9 years). Noninvasive measurement of their central hemodynamics was performed by analysis of the aortic pressure waveform derived from the radial artery. An increase in aortic fractional pulse pressure was associated with coronary artery narrowing or previous myocardial infarction. After multivariate adjustment, the odds ratio and confidence intervals (CI) of having a significant coronary aortic stenosis was 1.72 (95% CI, 1.1-2.7) and of previous myocardial infarction 1.6 (95% CI, 1.1-2.2). An increase in noninvasively assessed aortic fractional pulse pressure, but not of the peripheral index is significantly associated with the presence of coronary artery disease.

  3. Pressure Myography to Study the Function and Structure of isolated small arteries

    DEFF Research Database (Denmark)

    Schjørring, Olav; Carlsson, Rune; Simonsen, Ulf

    2015-01-01

    Small arteries play an important role in regulation of peripheral resistance and organ perfusion. Here we describe a series of the methods allowing measurements in pressurized segments of small arteries from the systemic and coronary circulation of mice as well as other species. The pressure myog...

  4. Classification of peripheral occlusive arterial diseases based on symptoms, signs and distal blood pressure measurements

    DEFF Research Database (Denmark)

    Tønnesen, K H; Noer, Ivan; Paaske, William

    1980-01-01

    Systolic blood pressures at toe and ankle were measured in 459 consecutive patients with occlusive arterial disease. Fifty-eight per cent had intermittent claudication with arterial disease of all degrees of severity. Seventeen per cent complained of rest pain having toe systolic pressures below 30...

  5. Phytoestrogen genistein decreases contractile response of aortic artery in vitro and arterial blood pressure in vivo

    Institute of Scientific and Technical Information of China (English)

    Hong-fang LI; Long-de WANG; Song-yi QU

    2004-01-01

    AIM: To determine the mechanisms of effects of phytoestrogen genistein on the contracted rabbit aortic arteries in vitro, and observe the effect of genistein and 17-β estradiol on mean arterial pressure (MAP) in ovariectomized (OVX) rats. METHODS: (1) Strips of rabbit aortic smooth muscle were suspended in organ baths containing Kreb's solution, and then isometric tension was measured. (2) Female mature Wistar rats underwent a bilateral ovariectomy (OVX). Sham-operated rats (SHAM) were used as controls. After administration of genistein (0.4(1) Similar to 17-β estradiol, genistein could dose-dependently relax 40 mmol/L KCl-precontracted arterial strips.Incubation with Nω-L-nitro-arginine (L-NNA), methylene blue (MB), indomethacin, propranolol or endothelium removal did not affect relaxation induced by genistein. In calcium-free solution containing 0.01mmol/L egtazic acid (EGTA), genistein inhibited not only the first phase contraction induced by noradrenaline (NA), but also the second contraction induced by CaCl2. In addition, genistein could reduce the contractile responses of NA, KCl and CaCl2,and shift their cumulative concentration-response curves rightward. (2) MAP in OVX rats was significantly higher compared with that of SHAM rats. However, after chronically treatment with genistein or 17-β estradiol for 21 d the baseline MAP in OVX rats was reduced significantly. CONCLUSIONS: (1) The vasodilator effect of genistein in vitro is endothelium independent and not related to the nitric oxide, its mechanisms being probably due to inhibition of Ca2+ influx through calcium channels in a noncompetitive manner and Ca2+ release from intracellular store induced by NA. (2) Administration of genistein or 17-β estradiol can chronically decrease MAP in OVX rats.

  6. Vasopressin contributes to maintenance of arterial blood pressure in dehydrated baboons.

    Science.gov (United States)

    Ryan, K L; Thornton, R M; Proppe, D W

    1989-02-01

    This study primarily sought to determine whether the role of vasopressin (VP) in maintenance of arterial blood pressure is enhanced in awake, chronically instrumented baboons after 68-72 h of dehydration. This question was approached by pharmacologically blocking vasopressin V1-receptors in euhydrated and dehydrated baboons with or without a normally functioning renin-angiotensin system (RAS). VP blockade during dehydration produced a rapidly occurring (within 5 min), statistically significant (P less than 0.05) decrease in mean arterial pressure (MAP) of 5 +/- 1 mmHg in the RAS-intact condition and an identical decline in MAP (5 +/- 1 mmHg) during blockade of the RAS by captopril, an angiotensin I-converting enzyme inhibitor. At 15 min after induction of VP blockade, heart rate was elevated by 9 +/- 2 beats/min in the RAS-intact condition and by 20 +/- 5 beats/min in the RAS-blocked condition. In addition, VP blockade in the dehydrated state produced small and equal increases in hindlimb vascular conductance in RAS-intact and RAS-blocked conditions. None of these cardiovascular changes were produced by VP blockade in the euhydrated state. RAS blockade produced modest declines in MAP in both hydration states, but the fall was larger by 7 +/- 4 mmHg in the dehydrated state. Thus both VP and the RAS contribute to the maintenance of arterial blood pressure during dehydration in the conscious baboon.

  7. Effect of Algerian Varieties Dates on Glycemic, Arterial Blood Pressure and Satiety Responses

    Directory of Open Access Journals (Sweden)

    Gourchala Freha, Mihoub Fatma, Derradj Meriem,\tHenchiri Cherifa

    2016-04-01

    Full Text Available The purpose of our study is to determine the Glycemic Indexes (GIsof three Algerians varieties of dates in healthy subjects, evaluate the satiety and effect on arterial pressure after their consumption. We have first documented the chemical composition of the dates. 10 healthy subjects consumed the dates (carbohydrates content of 50 g in order to determine the GIs. The responses of glycaemia were monitored during two hours after the dates taking and compared to the reference glucose. In a randomized trial, 20 healthy adults consumed the dates after 12h of fast. We reported the level of satiety on a Visual Analog Scale for 2h further to the ingestion of the dates. Furthermore, 28 normotensive and 45 hypertensive individuals ingested the three varieties in randomized order during 21 days to assess their impact on the Pressure Arterial Systolic (PAS and Pressure Arterial Diastolic (PAD. We noted significant differences (p<0.05 for the different fractions of sugars, soluble fibers, polyphenols, K+, Mg2+. The low GIs are denoted among 44.31-52.35, deducting a moderate impact on blood glucose level. The dates reduced hunger and increased satiety. Our varieties studied following their ingestion induced a significant hypotensive activity (p<0.05on the PAS and, PAD from hypertensive subjects.

  8. Determining the Arterial Blood Pressure of People Living in Yesilyurt Local Healthcare Office

    Directory of Open Access Journals (Sweden)

    Feyza Dereli

    2009-02-01

    Full Text Available AIM: Whereas the prevalance of arterial blood pressure which was a chronical health problem was 20%-25% among 30 year-old people, them showing an increase in aging, the percentage went as high as 50% in 60’s and later ages. What was that worrisome was that despite the high prevalance, only half of these received treathment. This is study was descriptively and cross-sectionally planned to determine whether the people asking their tensions to be measured in and around the Yesilyurt local healthcare office region. METHODS: The environment of the research consisted of 1400 people over 35 age and registered Yesilyurt Local healthcare Office and the whole of the environment were included in this sample. The study was conducted over 340 voluntaries. The data was collected by a questionnaire of 14 questions containing socio-demografic features and by measuring the arterial blood pressure, height and weight of the individuals. In the evaluation of the data, chi-square test was used and the level of significantly was accepted as 0.05. RESULTS: In this study, the rate of high sistolic blood pressure was found to be 21.47% and the rate of high diastolic blood pressure to be 8.23%. It was determined that age and body mass index varrieties were effective on sistolic hipertension. It was also found that in their behaviors of the use of hypertensive medicine, of regular arterial pressure controls and of having the hypertesion diagnosis significant differnces varied statistically on both sistolic and diastolic blood pressure people having. CONCLUSION: In order to improve the health, informative information abouth hypertension was provided for the participants for too days consisting of 4 sessions. [TAF Prev Med Bull 2009; 8(1.000: 53-58

  9. The Relation Between Aortic Pulse Pressure and Coronary Artery Disease

    Directory of Open Access Journals (Sweden)

    Ali Metin Esen

    2011-08-01

    Full Text Available Objective: Pulse pressure (PP is a significant marker of cardiovascular morbidity.We investigated the relation between aortic PP and the presence and extent of coronary artery disease (CAD in patients undergoing diagnostic coronary angiography (CAG.Patients and Method: The study group consisted of 550 patients (363 men, 187 women.We evaluated patients in two different groups, PP < 60 mmHg and ≥ 60 mmHg.Results: In univariate analysis gender and presence of hyperlipidemia showed no statistically significant differences between both groups. However, the ratio of patients having diabetes mellitus, hypertension or smoking were significantly higher in ≥ 60 mmHg PP group. The mean age was 55.2 ±11.9 in < 60 mmHg PP group and 61.3±9.3 in the other group (p<0.01. Although systolic blood pressure level was higher in ≥ 60 mmHg PP group (160.4±21.1 vs. 126.4±13.5, p< 0.001, diastolic blood pressure level showed no significant differences between both groups (78.3±13.5 vs. 80.3±10.2, p= 0.32. In the <60 mmHg PP group, the ratio of normal CAG was significantly higher, and also, the critically CAD rate was lower than the other group. In multivariate analysis, smoking [odds ratios (OR 2.344, 95% confidence intervals (CI, 1.416-3.879], male gender (OR 5.858, 95% CI, 3.425-10.019 and PP ≥60 mmHg (OR 25.788, 95% CI, 14.001-47.498 were evaluated as an independent indicators of CAD.Conclusions: In our study, we demonstrate that, aortic PP ≥60 mmHg is related to the risk of critically CAD as an independent factor.

  10. Influence of changes in the pulmonary artery pressure on ventilation requirements in patients undergoing mitral valve replacement.

    Directory of Open Access Journals (Sweden)

    Muralidhar K

    2004-01-01

    Full Text Available The study was designed to evaluate the influence of changes in pulmonary artery pressure on the ventilation requirements in patients undergoing mitral valve surgery. Thirty patients with mitral valve disease with significant pulmonary arterial hypertension undergoing mitral valve replacement under cardiopulmonary bypass were included in this prospective study. All patients had a pulmonary artery catheter placed after the anaesthetic induction. The minute ventilation was adjusted to achieve an arterial carbon dioxide tension (PaCO2 of 35-40 mm Hg. After a stabilisation period of 15 minutes, the pulmonary artery pressure and the minute volume needed for maintaining a PaCO2 of 35-40 mm Hg in the precardiopulmonary bypass, post-cardiopulmonary bypass and six hours postoperatively were measured after ensuring stable haemodynamics and normothermia. There was a significant decrease in the mean pulmonary artery pressure from pre-cardiopulmonary bypass value of 41.3+/-15 mm Hg to 29.3+/-8 mm Hg in the postcardiopulmonary bypass period and subsequently to 25.5+/-7 mm Hg in the intensive care unit. There was a corresponding increase in the minute volume requirements from a pre-cardiopulmonary bypass value of 6.8+/-1 L/min to 8.0+/-1 L/min in the post cardiopulmonary bypass period and then to 9.4+/-1.2 L/min in the postoperative period. We conclude that there is a significant decrease in the pulmonary blood volume and a subsequent decrease in the pulmonary artery pressure after a successful mitral valve replacement in patients with pulmonary arterial hypertension. This is associated with a significant increase in the requirement of minute ventilation to maintain normocarbia.

  11. PREDICTION OF BLOOD PATTERN IN S-SHAPED MODEL OF ARTERY UNDER NORMAL BLOOD PRESSURE

    Directory of Open Access Journals (Sweden)

    Mohd Azrul Hisham Mohd Adib

    2013-06-01

    Full Text Available Athletes are susceptible to a wide variety of traumatic and non-traumatic vascular injuries to the lower limb. This paper aims to predict the three-dimensional flow pattern of blood through an S-shaped geometrical artery model. This model has created by using Fluid Structure Interaction (FSI software. The modeling of the geometrical S-shaped artery is suitable for understanding the pattern of blood flow under constant normal blood pressure. In this study, a numerical method is used that works on the assumption that the blood is incompressible and Newtonian; thus, a laminar type of flow can be considered. The authors have compared the results with a previous study with FSI validation simulation. The validation and verification of the simulation studies is performed by comparing the maximum velocity at t = 0.4 s, because at this time, the blood accelerates rapidly. In addition, the resulting blood flow at various times, under the same boundary conditions in the S-shaped geometrical artery model, is presented. The graph shows that velocity increases linearly with time. Thus, it can be concluded that the flow of blood increases with respect to the pressure inside the body.

  12. Effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome

    Institute of Scientific and Technical Information of China (English)

    Mehri Najafi Sani; Hamid Reza Kianifar; Abdolrazagh Kianee; Gholamreza Khatami

    2006-01-01

    AIM: To study the effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome.METHODS: Garlic powder in a capsule form was given to 15 children with hepatopulmonary syndrome (confirmed by contrast echocardiography) at the dosage of 1g/1.73 m2 per day. Patients were evaluated clinically and by arterial blood gas every four weeks.RESULTS: The garlic capsule was administered to 15patients with hepatopulmonary syndrome. There were 10 boys and 5 girls with a mean age of 9.4±3.9 years.The underlying problems were biliary tract atresia (4patients), autoimmune hepatitis (4 patients), cryptogenic cirrhosis (4 patients) and presinusoidal portal hypertension (3 patients). Eight patients (53.3%) showed an increase of 10 mmHg in their mean arterial oxygen pressure. The baseline PaO2 was 65.6±12.1 mmHg in the responder group and 47.1±11.2 mmHg in nonresponder group. At the end of treatment the mean PaO2 in responders and non-responders was 92.2±7.75mmHg and 47.5±11.87 mmHg, respectively (P<0.01).CONCLUSION: Garlic may increase oxygenation and improve dyspnea in children with hepatopulmonary syndrome.

  13. Arterial blood pressure is closely related to ascites development in compensated HCV-related cirrhosis.

    Directory of Open Access Journals (Sweden)

    Eduardo Vilar Gomez

    Full Text Available BACKGROUND: Arterial blood pressure (BP is a reliable marker of circulatory dysfunction in cirrhotic patients. There are no prospective studies evaluating the association between different levels of arterial BP and ascites development in compensated cirrhotic patients. Therefore, we evaluated the relationship between arterial BP and ascites development in compensated cirrhotic patients. MATERIALS AND METHODS: A total of 402 patients with compensated HCV-related cirrhosis were prospectively followed during 6 years to identify ascites development. At baseline, patients underwent systolic, diastolic and mean arterial pressure (MAP measurements. Any history of arterial hypertension was also recorded. The occurrence of events such as bleeding, hepatocellular carcinoma, death and liver transplantation prior to ascites development were considered as competing risk events. RESULTS: Over a median of 156 weeks, ascites occurred in 54 patients (13%. At baseline, MAP was significantly lower in patients with ascites development (75.9 mm/Hg [95%CI, 70.3-84.3] than those without ascites (93.6 mm/Hg [95% CI: 86.6-102.3]. After adjusting for covariates, the 6-year cumulative incidence of ascites was 40% (95%CI, 34%-48% for patients with MAP<83.32 mm/Hg. In contrast, cumulative incidences of ascites were almost similar among patients with MAP values between 83.32 mm/Hg and 93.32 mm/Hg (7% [95% CI: 4%-12%], between 93.32 mm/Hg and 100.31 mm/Hg (5% [95% CI: 4%-11%] or higher than 100.31 mm/Hg (3% [95% CI: 1%-6%]. The MAP was an independent predictor of ascites development. CONCLUSIONS: The MAP is closely related to the development of ascites in compensated HCV-related cirrhosis. The risk of ascites development increases in 4.4 fold for subjects with MAP values <83.32 mm/Hg.

  14. Increased Mutagen Sensitivity and DNA Damage in Pulmonary Arterial Hypertension

    Science.gov (United States)

    Federici, Chiara; Drake, Kylie M.; Rigelsky, Christina M.; McNelly, Lauren N.; Meade, Sirena L.; Comhair, Suzy A. A.; Erzurum, Serpil C.

    2015-01-01

    Rationale: Pulmonary arterial hypertension (PAH) is a serious lung condition characterized by vascular remodeling in the precapillary pulmonary arterioles. We and others have demonstrated chromosomal abnormalities and increased DNA damage in PAH lung vascular cells, but their timing and role in disease pathogenesis is unknown. Objectives: We hypothesized that if DNA damage predates PAH, it might be an intrinsic cell property that is present outside the diseased lung. Methods: We measured DNA damage, mutagen sensitivity, and reactive oxygen species (ROS) in lung and blood cells from patients with Group 1 PAH, their relatives, and unrelated control subjects. Measurements and Main Results: Baseline DNA damage was significantly elevated in PAH, both in pulmonary artery endothelial cells (P < 0.05) and peripheral blood mononuclear cells (PBMC) (P < 0.001). Remarkably, PBMC from unaffected relatives showed similar increases, indicating this is not related to PAH treatments. ROS levels were also higher (P < 0.01). DNA damage correlated with ROS production and was suppressed by antioxidants (P < 0.001). PBMC from patients and relatives also showed markedly increased sensitivity to two chemotherapeutic drugs, bleomycin and etoposide (P < 0.001). Results were consistent across idiopathic, heritable, and associated PAH groups. Conclusions: Levels of baseline and mutagen-induced DNA damage are intrinsically higher in PAH cells. Similar results in PBMC from unaffected relatives suggest this may be a genetically determined trait that predates disease onset and may act as a risk factor contributing to lung vascular remodeling following endothelial cell injury. Further studies are required to fully characterize mutagen sensitivity, which could have important implications for clinical management. PMID:25918951

  15. Mean arterial pressure following prolonged exercise in the heat

    DEFF Research Database (Denmark)

    Gagnon, D; Lynn, A G; Binder, K

    2012-01-01

    benefit to its regulation. We examined MAP (Finometer) in eight trained (T) and eight untrained (UT) individuals prior to, and following, 120 min of cycling at 42 °C with (HYD) and without (DEHY) fluid replacement. Exercise during DEHY induced significant hyperthermia (T: 39.20 ± 0.52 °C vs UT: 38.70 ± 0......Prolonged exercise in the heat without fluid replacement represents a significant challenge to the regulation of mean arterial pressure (MAP). It is unknown, however, if MAP is equally challenged during the post-exercise period, and whether regular endurance exercise training can provide any.......36 °C, P = 0.941) and body weight losses (T: 3.4 ± 1.2% vs UT: 2.7 ± 0.9%, P = 0.332), which did not differ between groups. Although MAP was equally reduced 5 min into the post-exercise period of DEHY (T: -20 ± 11 mmHg vs UT: -22 ± 13 mmHg, P = 0.800), its subsequent recovery was significantly different...

  16. Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure

    Science.gov (United States)

    Wain, Louise V; Verwoert, Germaine C; O’Reilly, Paul F; Shi, Gang; Johnson, Toby; Johnson, Andrew D; Bochud, Murielle; Rice, Kenneth M; Henneman, Peter; Smith, Albert V; Ehret, Georg B; Amin, Najaf; Larson, Martin G; Mooser, Vincent; Hadley, David; Dörr, Marcus; Bis, Joshua C; Aspelund, Thor; Esko, Tõnu; Janssens, A Cecile JW; Zhao, Jing Hua; Heath, Simon; Laan, Maris; Fu, Jingyuan; Pistis, Giorgio; Luan, Jian’an; Arora, Pankaj; Lucas, Gavin; Pirastu, Nicola; Pichler, Irene; Jackson, Anne U; Webster, Rebecca J; Zhang, Feng; Peden, John F; Schmidt, Helena; Tanaka, Toshiko; Campbell, Harry; Igl, Wilmar; Milaneschi, Yuri; Hotteng, Jouke-Jan; Vitart, Veronique; Chasman, Daniel I; Trompet, Stella; Bragg-Gresham, Jennifer L; Alizadeh, Behrooz Z; Chambers, John C; Guo, Xiuqing; Lehtimäki, Terho; Kühnel, Brigitte; Lopez, Lorna M; Polašek, Ozren; Boban, Mladen; Nelson, Christopher P; Morrison, Alanna C; Pihur, Vasyl; Ganesh, Santhi K; Hofman, Albert; Kundu, Suman; Mattace-Raso, Francesco US; Rivadeneira, Fernando; Sijbrands, Eric JG; Uitterlinden, Andre G; Hwang, Shih-Jen; Vasan, Ramachandran S; Wang, Thomas J; Bergmann, Sven; Vollenweider, Peter; Waeber, Gérard; Laitinen, Jaana; Pouta, Anneli; Zitting, Paavo; McArdle, Wendy L; Kroemer, Heyo K; Völker, Uwe; Völzke, Henry; Glazer, Nicole L; Taylor, Kent D; Harris, Tamara B; Alavere, Helene; Haller, Toomas; Keis, Aime; Tammesoo, Mari-Liis; Aulchenko, Yurii; Barroso, Inês; Khaw, Kay-Tee; Galan, Pilar; Hercberg, Serge; Lathrop, Mark; Eyheramendy, Susana; Org, Elin; Sõber, Siim; Lu, Xiaowen; Nolte, Ilja M; Penninx, Brenda W; Corre, Tanguy; Masciullo, Corrado; Sala, Cinzia; Groop, Leif; Voight, Benjamin F; Melander, Olle; O’Donnell, Christopher J; Salomaa, Veikko; d’Adamo, Adamo Pio; Fabretto, Antonella; Faletra, Flavio; Ulivi, Sheila; Del Greco, M Fabiola; Facheris, Maurizio; Collins, Francis S; Bergman, Richard N; Beilby, John P; Hung, Joseph; Musk, A William; Mangino, Massimo; Shin, So-Youn; Soranzo, Nicole; Watkins, Hugh; Goel, Anuj; Hamsten, Anders; Gider, Pierre; Loitfelder, Marisa; Zeginigg, Marion; Hernandez, Dena; Najjar, Samer S; Navarro, Pau; Wild, Sarah H; Corsi, Anna Maria; Singleton, Andrew; de Geus, Eco JC; Willemsen, Gonneke; Parker, Alex N; Rose, Lynda M; Buckley, Brendan; Stott, David; Orru, Marco; Uda, Manuela; van der Klauw, Melanie M; Zhang, Weihua; Li, Xinzhong; Scott, James; Chen, Yii-Der Ida; Burke, Gregory L; Kähönen, Mika; Viikari, Jorma; Döring, Angela; Meitinger, Thomas; Davies, Gail; Starr, John M; Emilsson, Valur; Plump, Andrew; Lindeman, Jan H; ’t Hoen, Peter AC; König, Inke R; Felix, Janine F; Clarke, Robert; Hopewell, Jemma C; Ongen, Halit; Breteler, Monique; Debette, Stéphanie; DeStefano, Anita L; Fornage, Myriam; Mitchell, Gary F; Smith, Nicholas L; Holm, Hilma; Stefansson, Kari; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Samani, Nilesh J; Preuss, Michael; Rudan, Igor; Hayward, Caroline; Deary, Ian J; Wichmann, H-Erich; Raitakari, Olli T; Palmas, Walter; Kooner, Jaspal S; Stolk, Ronald P; Jukema, J Wouter; Wright, Alan F; Boomsma, Dorret I; Bandinelli, Stefania; Gyllensten, Ulf B; Wilson, James F; Ferrucci, Luigi; Schmidt, Reinhold; Farrall, Martin; Spector, Tim D; Palmer, Lyle J; Tuomilehto, Jaakko; Pfeufer, Arne; Gasparini, Paolo; Siscovick, David; Altshuler, David; Loos, Ruth JF; Toniolo, Daniela; Snieder, Harold; Gieger, Christian; Meneton, Pierre; Wareham, Nicholas J; Oostra, Ben A; Metspalu, Andres; Launer, Lenore; Rettig, Rainer; Strachan, David P; Beckmann, Jacques S; Witteman, Jacqueline CM; Erdmann, Jeanette; van Dijk, Ko Willems; Boerwinkle, Eric; Boehnke, Michael; Ridker, Paul M; Jarvelin, Marjo-Riitta; Chakravarti, Aravinda; Abecasis, Goncalo R; Gudnason, Vilmundur; Newton-Cheh, Christopher; Levy, Daniel; Munroe, Patricia B; Psaty, Bruce M; Caulfield, Mark J; Rao, Dabeeru C

    2012-01-01

    Numerous genetic loci influence systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans 1-3. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N=74,064) and follow-up studies (N=48,607), we identified at genome-wide significance (P= 2.7×10-8 to P=2.3×10-13) four novel PP loci (at 4q12 near CHIC2/PDGFRAI, 7q22.3 near PIK3CG, 8q24.12 in NOV, 11q24.3 near ADAMTS-8), two novel MAP loci (3p21.31 in MAP4, 10q25.3 near ADRB1) and one locus associated with both traits (2q24.3 near FIGN) which has recently been associated with SBP in east Asians. For three of the novel PP signals, the estimated effect for SBP was opposite to that for DBP, in contrast to the majority of common SBP- and DBP-associated variants which show concordant effects on both traits. These findings indicate novel genetic mechanisms underlying blood pressure variation, including pathways that may differentially influence SBP and DBP. PMID:21909110

  17. Post-weaning protein malnutrition increases blood pressure and induces endothelial dysfunctions in rats.

    Science.gov (United States)

    de Belchior, Aucelia C S; Angeli, Jhuli K; Faria, Thaís de O; Siman, Fabiana D M; Silveira, Edna A; Meira, Eduardo F; da Costa, Carlos P; Vassallo, Dalton V; Padilha, Alessandra S

    2012-01-01

    Malnutrition during critical periods in early life may increase the subsequent risk of hypertension and metabolic diseases in adulthood, but the underlying mechanisms are still unclear. We aimed to evaluate the effects of post-weaning protein malnutrition on blood pressure and vascular reactivity in aortic rings (conductance artery) and isolated-perfused tail arteries (resistance artery) from control (fed with Labina®) and post-weaning protein malnutrition rats (offspring that received a diet with low protein content for three months). Systolic and diastolic blood pressure and heart rate increased in the post-weaning protein malnutrition rats. In the aortic rings, reactivity to phenylephrine (10(-10)-3.10(-4) M) was similar in both groups. Endothelium removal or L-NAME (10(-4) M) incubation increased the response to phenylephrine, but the L-NAME effect was greater in the aortic rings from the post-weaning protein malnutrition rats. The protein expression of the endothelial nitric oxide isoform increased in the aortic rings from the post-weaning protein malnutrition rats. Incubation with apocynin (0.3 mM) reduced the response to phenylephrine in both groups, but this effect was higher in the post-weaning protein malnutrition rats, suggesting an increase of superoxide anion release. In the tail artery of the post-weaning protein malnutrition rats, the vascular reactivity to phenylephrine (0.001-300 µg) and the relaxation to acetylcholine (10(-10)-10(-3) M) were increased. Post-weaning protein malnutrition increases blood pressure and induces vascular dysfunction. Although the vascular reactivity in the aortic rings did not change, an increase in superoxide anion and nitric oxide was observed in the post-weaning protein malnutrition rats. However, in the resistance arteries, the increased vascular reactivity may be a potential mechanism underlying the increased blood pressure observed in this model.

  18. Post-weaning protein malnutrition increases blood pressure and induces endothelial dysfunctions in rats.

    Directory of Open Access Journals (Sweden)

    Aucelia C S de Belchior

    Full Text Available Malnutrition during critical periods in early life may increase the subsequent risk of hypertension and metabolic diseases in adulthood, but the underlying mechanisms are still unclear. We aimed to evaluate the effects of post-weaning protein malnutrition on blood pressure and vascular reactivity in aortic rings (conductance artery and isolated-perfused tail arteries (resistance artery from control (fed with Labina® and post-weaning protein malnutrition rats (offspring that received a diet with low protein content for three months. Systolic and diastolic blood pressure and heart rate increased in the post-weaning protein malnutrition rats. In the aortic rings, reactivity to phenylephrine (10(-10-3.10(-4 M was similar in both groups. Endothelium removal or L-NAME (10(-4 M incubation increased the response to phenylephrine, but the L-NAME effect was greater in the aortic rings from the post-weaning protein malnutrition rats. The protein expression of the endothelial nitric oxide isoform increased in the aortic rings from the post-weaning protein malnutrition rats. Incubation with apocynin (0.3 mM reduced the response to phenylephrine in both groups, but this effect was higher in the post-weaning protein malnutrition rats, suggesting an increase of superoxide anion release. In the tail artery of the post-weaning protein malnutrition rats, the vascular reactivity to phenylephrine (0.001-300 µg and the relaxation to acetylcholine (10(-10-10(-3 M were increased. Post-weaning protein malnutrition increases blood pressure and induces vascular dysfunction. Although the vascular reactivity in the aortic rings did not change, an increase in superoxide anion and nitric oxide was observed in the post-weaning protein malnutrition rats. However, in the resistance arteries, the increased vascular reactivity may be a potential mechanism underlying the increased blood pressure observed in this model.

  19. Short-term effects of nitrate-rich green leafy vegetables on blood pressure and arterial stiffness in individuals with high-normal blood pressure.

    Science.gov (United States)

    Bondonno, Catherine P; Liu, Alex H; Croft, Kevin D; Ward, Natalie C; Yang, Xingbin; Considine, Michael J; Puddey, Ian B; Woodman, Richard J; Hodgson, Jonathan M

    2014-12-01

    Evidence for a beneficial effect of dietary nitrate, through the nitrate-nitrite-NO pathway, on measures of cardiovascular function in healthy individuals is accumulating. It is less clear whether increased dietary nitrate intake from green leafy vegetables would have similar beneficial vascular effects in those at increased risk of developing hypertension. Our aim was to assess the effects of short-term regular consumption of increased nitrate from green leafy vegetables on blood pressure and arterial stiffness in individuals with high-normal blood pressure. Thirty-eight men and women ages 30-70 years with systolic blood pressure 120 to 139 mm Hg were recruited to a randomized controlled crossover trial. The effects of a 7-day high-nitrate diet intervention (increased nitrate intake by at least 300 mg/day from green leafy vegetables) were compared to a 7-day low-nitrate diet intervention. Outcome measures included pre- and postintervention salivary and plasma nitrate and nitrite concentrations; ambulatory, home, and office blood pressure; augmentation index; and carotid-femoral pulse wave velocity. The high-nitrate diet intervention resulted in at least a fourfold increase in salivary and plasma nitrate and nitrite (Pblood pressure and arterial stiffness were not different between the high-nitrate diet and the low-nitrate diet. Increasing dietary nitrate intake in those with high-normal blood pressure and at increased risk of hypertension may not be an effective short-term strategy to lower blood pressure.

  20. Predicting Increased Blood Pressure Using Machine Learning

    Directory of Open Access Journals (Sweden)

    Hudson Fernandes Golino

    2014-01-01

    Full Text Available The present study investigates the prediction of increased blood pressure by body mass index (BMI, waist (WC and hip circumference (HC, and waist hip ratio (WHR using a machine learning technique named classification tree. Data were collected from 400 college students (56.3% women from 16 to 63 years old. Fifteen trees were calculated in the training group for each sex, using different numbers and combinations of predictors. The result shows that for women BMI, WC, and WHR are the combination that produces the best prediction, since it has the lowest deviance (87.42, misclassification (.19, and the higher pseudo R2 (.43. This model presented a sensitivity of 80.86% and specificity of 81.22% in the training set and, respectively, 45.65% and 65.15% in the test sample. For men BMI, WC, HC, and WHC showed the best prediction with the lowest deviance (57.25, misclassification (.16, and the higher pseudo R2 (.46. This model had a sensitivity of 72% and specificity of 86.25% in the training set and, respectively, 58.38% and 69.70% in the test set. Finally, the result from the classification tree analysis was compared with traditional logistic regression, indicating that the former outperformed the latter in terms of predictive power.

  1. Predicting Increased Blood Pressure Using Machine Learning

    Science.gov (United States)

    Golino, Hudson Fernandes; Amaral, Liliany Souza de Brito; Duarte, Stenio Fernando Pimentel; Soares, Telma de Jesus; dos Reis, Luciana Araujo

    2014-01-01

    The present study investigates the prediction of increased blood pressure by body mass index (BMI), waist (WC) and hip circumference (HC), and waist hip ratio (WHR) using a machine learning technique named classification tree. Data were collected from 400 college students (56.3% women) from 16 to 63 years old. Fifteen trees were calculated in the training group for each sex, using different numbers and combinations of predictors. The result shows that for women BMI, WC, and WHR are the combination that produces the best prediction, since it has the lowest deviance (87.42), misclassification (.19), and the higher pseudo R2 (.43). This model presented a sensitivity of 80.86% and specificity of 81.22% in the training set and, respectively, 45.65% and 65.15% in the test sample. For men BMI, WC, HC, and WHC showed the best prediction with the lowest deviance (57.25), misclassification (.16), and the higher pseudo R2 (.46). This model had a sensitivity of 72% and specificity of 86.25% in the training set and, respectively, 58.38% and 69.70% in the test set. Finally, the result from the classification tree analysis was compared with traditional logistic regression, indicating that the former outperformed the latter in terms of predictive power. PMID:24669313

  2. Myogenic constriction is increased in mesenteric resistance arteries from rats with chronic heart failure : instantaneous counteraction by acute AT(1) receptor blockade

    NARCIS (Netherlands)

    Gschwend, S; Henning, RH; Pinto, YM; de Zeeuw, D; van Gilst, WH; Buikema, H

    2003-01-01

    1 Increased vascular resistance in chronic heart failure (CHF) has been attributed to stimulated neurohumoral systems. However, local mechanisms may also importantly contribute to set arterial tone. Our aim, therefore, was to test whether pressure-induced myogenic constriction of resistance arteries

  3. Dependency of cerebral blood flow upon mean arterial pressure in patients with acute bacterial meningitis

    DEFF Research Database (Denmark)

    Møller, Kirsten; Larsen, Fin Stolze; Qvist, Jesper;

    2000-01-01

    OBJECTIVE: Patients with acute bacterial meningitis are often treated with sympathomimetics to maintain an adequate mean arterial pressure (MAP). We studied the influence of such therapy on cerebral blood flow (CBF). DESIGN: Prospective physiologic trial. SETTING: The Department of Infectious...... Diseases, Copenhagen University Hospital, Denmark. PATIENTS: Sixteen adult patients with acute bacterial meningitis. INTERVENTION: Infusion of norepinephrine to increase MAP. MEASUREMENTS: During a rise in MAP induced by norepinephrine infusion, we measured relative changes in CBF by transcranial Doppler...... bacterial meningitis, CBF autoregulation is impaired. With recovery from meningitis, the cerebral vasculature regains the ability to maintain cerebral perfusion at a constant level despite variations in MAP....

  4. Influence of geomagnetic activity and atmospheric pressure on human arterial pressure during the solar cycle 24

    Science.gov (United States)

    Azcárate, T.; Mendoza, B.; Levi, J. R.

    2016-11-01

    We performed a study of the systolic (SBP) and diastolic (DBP) arterial blood pressure behavior under natural variables such as the atmospheric pressure (AtmP) and the horizontal geomagnetic field component (H). We worked with a sample of 304 healthy normotense volunteers, 152 men and 152 women, with ages between 18 and 84 years in Mexico City during the period 2008-2014, corresponding to the minimum, ascending and maximum phases of the solar cycle 24. The data was divided by gender, age and day/night cycle. We studied the time series using three methods: Correlations, bivariate and superposed epochs (within a window of three days around the day of occurrence of a geomagnetic storm) analysis, between the SBP and DBP and the natural variables (AtmP and H). The correlation analysis indicated correlation between the SBP and DBP and AtmP and H, being the largest during the night. Furthermore, the correlation and bivariate analysis showed that the largest correlations are between the SBP and DBP and the AtmP. The superposed epoch analysis found that the largest number of significant SBP and DBP changes occurred for women. Finally, the blood pressure changes are larger during the solar minimum and ascending solar cycle phases than during the solar maximum; the storms of the minimum were more intense than those of the maximum and this could be the reason of behavior of the blood pressure changes along the solar cycle.

  5. Arterial compliance in patients with cirrhosis: stroke volume-pulse pressure ratio as simplified index

    DEFF Research Database (Denmark)

    Henriksen, J H; Fuglsang, Stefan; Bendtsen, Flemming;

    2001-01-01

    Arterial function may be altered in patients with cirrhosis. We determined compliance of the arterial tree (C(1)) in relation to systemic and splanchnic hemodynamic derangement and clinical variables. C(1) and the stroke volume-pulse pressure index (SV/PP) were significantly higher (+62% and +40...... predictors of SV/PP (P index seems to reflect abnormalities in the arterial compliance of these patients....

  6. Relationship between pulmonary arterial pressure and pulmonary thromboembolism associated with dead worms in canine heartworm disease.

    Science.gov (United States)

    Hirano, Y; Kitagawa, H; Sasaki, Y

    1992-10-01

    To examine effects of thromboemboli due to dead worms on pulmonary arterial pressure (PAP), 20 to 50 dead heartworms were inserted into the pulmonary arteries of 4 heartworm uninfected dogs (uninfected group) and 11 dogs infected with heartworms (infected group). In the uninfected group, the mean PAP rose 1 week after worm insertion (10.9 to 166. mmHg), but it recovered by the 4th week. Clinical signs, hemodynamics and blood gas findings also deteriorated at the 1st week, but recovered at the 4th week. Angiographic and pathological findings indicated that blood flow recovered through the spaces between thromboemboli and vessel walls at the 4th week. The infected dogs were divided into three groups. In the infected-I group (5 dogs), the intimal lesions of the pulmonary arteries were slight, and clinical and laboratory findings showed changes similar to those of the uninfected group. In the infected-II group (4 dogs), the pulmonary arterial lesions were severe and the mean PAP was higher (25.7 mmHg) than in the uninfected group before worm insertion. An increase in PAP (34.1 mmHg) and worsening of clinical and laboratory findings were noticed till the 4th week. Thromboemboli adhered extensively to the vessel walls. Two dogs in the infected-III group died of severe dyspnea on the 9th and 10th day, and the mean PAP rose remarkably at the 1st week (from 19.4 to 28.2 mmHg). Severe pulmonary parenchymal lesions with edema or perforation were observed. From the above results, it was clarified that effects of dead worms on PAP and clinical signs depended on the severity of pulmonary arterial lesions before worm insertion.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Validation of continuous noninvasive arterial blood pressure measurements during general anesthesia

    NARCIS (Netherlands)

    Kalmar, A.F.; Vos, Jaap Jan; Weening, M.; Mooyaart, E.A.; Poterman, Marieke; Struys, Michel; Scheeren, Thomas

    2012-01-01

    Background:  Continuous invasive arterial blood pressure (IBP) monitoring remains the accepted gold standard for blood pressure monitoring because of its high accuracy. Several disadvantages of this method motivate the use of noninvasive intermittent blood pressure (NIBP) in most anesthesia cases de

  8. A rapid decrease in pulmonary arterial pressure by noninvasive positive pressure ventilation in a patient with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Dursunoglu Nese

    2007-01-01

    Full Text Available The natural history of chronic obstructive pulmonary disease (COPD is characterized by progressive decrements in expiratory airflow, increments in end-expired pulmonary volume, hypoxaemia, hypercapnia and the progression of pulmonary arterial hypertension (PAH. Noninvasive positive pressure ventilation (NPPV treatment is increasingly used for the treatment of acute and chronic respiratory failure in patients with COPD. NPPV can increase PaO2 and decrease PaCO2 by correcting the gas exchange in such patients. The acute effect of NPPV on decreasing PAP is seen in patients with respiratory failure, probably due to the effect on cardiac output. Here, a case with COPD whose respiratory acidosis and PAH rapidly improved by NPPV was presented and therefore we suggested to perform an echocardiographic assessment to reveal an improvement of PAH as well as respiratory acidosis, hypercapnia and hypoxemia with that treatment.

  9. An Inexpensive Arterial Pressure Wave Sensor and its application in different physiological condition

    CERN Document Server

    Sur, S; Sur, Shantanu

    2005-01-01

    Arterial Blood Pressure wave monitoring is considered to be important in assessment of cardiovascular system. We developed a novel pulse wave detection system using low frequency specific piezoelectric material as pressure wave sensor. The transducer detects the periodic change in the arterial wall diameter produced by pressure wave and the amplified signal after integration represents the pressure wave. The signal before integration is proportional to the rate of change of pressure wave and it not only reproduces the pressure waveform faithfully, but also its sharper nature helps to reliably detect the heart period variability (HPV). We have studied the position-specific (e.g. over carotid or radial artery) nature of change of this pulse wave signal (shape and amplitude) and also the changes at different physiological states.

  10. Arterial Pulse Pressure and Its Association With Reduced Stroke Volume During Progressive Central Hypovolemia

    Science.gov (United States)

    2006-09-01

    Measurement of Stroke Volume Stroke volume (SV) was measured noninvasively using thoracic electrical bioimpedance (TEB). TEB was measured using four...tients who did not die. For the current study, we measured mean arterial blood pressure (MAP), pulse pressure (PP), SV, and muscle sympathetic nerve...hemorrhagic shock. The vital sign monitors placed in emergency transport vehicles provide the medic with routine measures of arterial systolic, diastolic and

  11. Non-invasive assessment of pulmonary arterial pressure in healthy neonates.

    OpenAIRE

    Skinner, J. R.; Boys, R J; Hunter, S; Hey, E N

    1991-01-01

    Doppler echocardiograms were carried out on 51 healthy babies three times during the first 72 hours of life to estimate pulmonary arterial systolic pressure by measuring regurgitant tricuspid jet velocity and applying the Bernoulli equation. Tricuspid regurgitation was detected at some stage in all preterm babies and most of those born at full term. Pulmonary arterial pressure could be measured from peak regurgitant velocity in babies with pansystolic regurgitation. The incidence of pansystol...

  12. Left Ventricular Mass index and Pulmonary Artery Pressure in Patients with the Obstructive Sleep Apnea Syndrome

    Directory of Open Access Journals (Sweden)

    Seyed Hashem Sezavar

    2016-07-01

    Full Text Available Background: Sleep apnea is accompanied by some cardiovascular complications. It has even been hypothesized that sleep apnea, itself, can induce some of these complications. Given such controversies, we assessed the left ventricular mass index (LVMI and systolic pulmonary artery pressure in patients with sleep apnea.Methods: Through convenience sampling, 56 patients with the obstructive sleep apnea syndrome (OSAS were included in the present descriptive cross-sectional study. Patients with any past history of hypertension and diabetes mellitus were excluded. The apnea severity was assessed via the polysomnography-derived apnea-hypopnea index (AHI. All the patients underwent transthoracic echocardiography. In this cross-sectional study - data regarding age, gender, smoking, systolic and diastolic blood pressures, polysomnographic parameters (AHI, severity of disease, mean heart rate, mean oxygen saturation [SaO2], lowest SaO2, and duration of SaO2 below 90% [d.SaO2 < 90%], and  echocardiographic parameters (systolic pulmonary artery pressure and LVMI were accumulated and processed.Results: Fifty-two men and 14 women at a mean age of 49.29 ± 11.79 years participated in this study. Systolic and was significantly high in the severe group compared with the mild group (128.21 ± 9.73 mmHg vs. 119.23 ± 12.5 mmHg; p value = 0.007. The LVMI was increased parallel to an increase in the severity of the OSAS, but that increase was not statistically significant (p value = 0.161. The d.SaO2 < 90% was positively correlated with the LVMI, and this relationship remained true after adjustment for the body mass index (r = 0.27; p value = 0.042.Conclusion: Severe OSAS was accompanied by a higher blood pressure. The LVMI did not differ significantly between the patients with the OSAS and those who did not suffer from other risk factors of cardiac diseases.

  13. Changes in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure in men and women with primary open angle glaucoma

    Directory of Open Access Journals (Sweden)

    Marjanović Ivan

    2013-01-01

    Full Text Available Introduction. An altered perfusion of the optic nerve head has been proposed as a pathogenic factor of glaucoma. Objective. The aim of this study was to evaluate the changes of the hemodynamic parameters in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure (IOP in women and men with primary open angle glaucoma. Methods. The study included 60 patients (33 males and 27 females older than 50 years, with diagnosed and treated primary open angle glaucoma (77 eyes of 39 patients had increased IOP, >25 mm Hg. They were examined at the Clinic of Eye Diseases (complete ophthalmologic exam and Clinic of Neurology, Clinical Center of Serbia, Belgrade, from December 2009 to December 2010. Imaging of hemodynamic parameters of three retrobulbar arterial vessels: ophthalmic, central retinal and posterior ciliary arteries with color Doppler was performed. Results. Among women, hemodynamic arterial parameter of the peak-systolic velocity was increased in the central retinal artery and decreased in the ophthalmic artery and posterior ciliary arteries; end- diastolic velocity was increased in all three retrobulbar vascular levels; Pourcelot resistivity index was increased, but pulsatility index was decreased in all three vessels. Among men, peak-systolic velocity, end-diastolic velocity and pulsatility index were decreased in all three vessels; resistivity index was increased in the ophthalmic artery, but decreased in the central retinal artery and posterior ciliary arteries. There was a significant change of the ophthalmic artery pulsatility index in women, and the end-diastolic velocity of the ophthalmic artery in men. Conclusion. There was a difference of the retrobulbar arterial circulation between women and men with primary open angle glaucoma after decrease of the elevated intraocular pressure. The role of vascular factors in the supply of the optic disc neuroretinal rim is important.

  14. Skin autofluorescence is increased in patients with carotid artery stenosis and peripheral artery disease

    NARCIS (Netherlands)

    Noordzij, Marjon J.; Lefrandt, Joop D.; Loeffen, Erik A. H.; Saleem, Ben R.; Meerwaldt, Robbert; Lutgers, Helen L.; Smit, Andries J.; Zeebregts, Clark J.

    2012-01-01

    Advanced glycation end products (AGEs) have a pivotal role in atherosclerosis. We evaluated skin autofluorescence (SAF), a non-invasive measurement of tissue AGE accumulation, in patients with carotid artery stenosis with and without coexisting peripheral artery occlusive disease (PAOD). SAF was mea

  15. Mini invasive hemodynamic monitoring: from arterial pressure to cardiac output

    OpenAIRE

    Della Rocca, Giorgio; Cecconi, Maurizio; Costa, Maria Gabriella

    2008-01-01

    To evaluate the Cardiac Output (CO) the standard invasive pulmonary artery catheter (PAC) is considered today the gold standard. The major criticism to the PAC is that its level of invasiveness is not supported by an improvement in patient's outcome. The interest to lesser and lesser invasive techniques is high. Therefore, the alternative techniques have been recently developed.Cardiac Output can be monitored continuously by different devices that analyze the arterial waveform to track change...

  16. Testosterone suppression in men with prostate cancer leads to an increase in arterial stiffness and hyperinsulinaemia.

    Science.gov (United States)

    Dockery, Frances; Bulpitt, Christopher J; Agarwal, Sanjiv; Donaldson, Mandy; Rajkumar, Chakravarthi

    2003-02-01

    The role of androgens in cardiovascular disease is uncertain. We aimed to determine the vascular effects of androgen suppression in men with prostate cancer. Arterial stiffness (or 'compliance') was measured in 16 men (71+/-9 years, mean+/-S.D.) prior to, and 3 months after, complete androgen suppression with gonadotrophin-releasing hormone analogues as treatment for prostate cancer. Fifteen control men (70+/-7 years) also had arterial stiffness studies at baseline and 3 months later. Two measures of arterial stiffness were employed: systemic arterial compliance (SAC) was measured by simultaneous recording of aortic flow and carotid artery pressure ('area method'), and pulse wave velocities (PWVs) were recorded with the 'Complior' system. The 16 cases underwent glucose-tolerance and fasting-lipids tests on both visits. After 3 months of testosterone suppression, there was a significant fall in SAC, which was not seen in the controls [mean change+/-S.E.M., -0.26+/-0.09 a.c.u. (arbitrary compliance unit) in the cases versus +0.06+/-0.11 in the controls; P =0.03). Central, but not peripheral, PWVs tended to increase in the cases (mean change+/-S.E.M. for aorto-femoral PWV, +0.5+/-0.4 m/s for cases versus -0.3+/-0.3 m/s for controls; P =0.08). After testosterone suppression, fasting insulin levels increased from 6.89+/-4.84 m-units/l to 11.34+/-8.16 m-units/l (mean+/-S.D.), total cholesterol increased from 5.32+/-0.77 mmol/l to 5.71+/-0.82 mmol/l and high-density lipoprotein cholesterol increased from 1.05+/-0.24 mmol/l to 1.26+/-0.36 mmol/l; P change occurred in body-mass index, serum glucose, low-density lipoprotein cholesterol or triacylglycerol (triglyceride) levels. Our results indicate that loss of androgens in men leads to an increase in aortic stiffness and serum insulin levels, and may therefore adversely affect cardiovascular risk.

  17. Increased LDL susceptibility to oxidation accelerates future carotid artery atherosclerosis

    Directory of Open Access Journals (Sweden)

    Aoki Toshinari

    2012-01-01

    Full Text Available Abstract Background We analyzed the causal relationship between LDL susceptibility to oxidation and the development of new carotid artery atherosclerosis over a period of 5 years. We previously described the determinants related to a risk of cardiovascular changes determined in a Japanese population participating in the Niigata Study, which is an ongoing epidemiological investigation of the prevention of cardiovascular diseases. Methods We selected 394 individuals (169 males and 225 females who underwent a second carotid artery ultrasonographic examination in 2001 - 2002 for the present study. The susceptibility of LDL to oxidation was determined as the photometric absorbance and electrophoretic mobility of samples that had been collected in 1996 - 1997. The measurements were compared with ultrasonographic findings obtained in 2001 - 2002. Results The multivariate-adjusted model showed that age (odds ratio (OR, 1.034; 95% confidence interval (95%CI, 1.010 - 1.059, HbA1c (OR, 1.477; 95%CI, 0.980 - 2.225, and photometric O/N (OR, 2.012; 95%CI, 1.000 - 4.051 were significant variables that could independently predict the risk of new carotid artery atherosclerosis. Conclusion The susceptibility of LDL to oxidation was a significant parameter that could predict new carotid artery atherosclerosis over a 5-year period, and higher susceptibility was associated with a higher incidence of new carotid artery atherosclerosis.

  18. Impaired renal allograft function is associated with increased arterial stiffness in renal transplant recipients

    DEFF Research Database (Denmark)

    Kneifel, M; Scholze, A; Burkert, A;

    2006-01-01

    It is important whether impairment of renal allograft function may deteriorate arterial stiffness in renal transplant recipients. In a cross-sectional study, arterial vascular characteristics were non-invasively determined in 48 patients with renal allograft using applanation tonometry and digital...... of large arteries S1 and small arteries S2 in renal transplant recipients (each p renal allograft (p ...-Wallis test between groups). It is concluded that impairment of renal allograft function is associated with an increased arterial stiffness in renal transplant recipients....

  19. Arterial pressure and cerebral blood flow variability: friend or foe? A review

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    Caroline Alice Rickards

    2014-04-01

    Full Text Available Variability in arterial pressure and cerebral blood flow has traditionally been interpreted as a marker of cardiovascular decompensation, and has been associated with negative clinical outcomes across varying time scales, from impending orthostatic syncope to an increased risk of stroke. Emerging evidence, however, suggests that increased hemodynamic variability may, in fact, be protective in the face of acute challenges to perfusion, including significant central hypovolemia and hypotension (including hemorrhage, and during cardiac bypass surgery. This review presents the dichotomous views on the role of hemodynamic variability on clinical outcome, including the physiological mechanisms underlying these patterns, and the potential impact of increased and decreased variability on cerebral perfusion and oxygenation. We suggest that reconciliation of these two apparently discrepant views may lie in the time scale of hemodynamic variability; short time scale variability appears to be cerebroprotective, while mid to longer term fluctuations are associated with primary and secondary end-organ dysfunction.

  20. Altered ATP-sensitive potassium channels may underscore obesity-triggered increase in blood pressure

    Institute of Scientific and Technical Information of China (English)

    Li-hong FAN; Hong-yan TIAN; Ai-qun MA; Zhi HU; Jian-hua HUO; Yong-xiao CAO

    2008-01-01

    Aim:To determine whether ATP-sensitive potassium channels are altered in VSMC from arotas and mesenteric arteries of obese rat,and their association with obesity-triggered increase in blood pressure.Methods:Obesity was induced by 24 weeks of high-fat diet feeding in male Sprague-Dawley rats.Control rats were fed with standard laboratory rat chow.Blood pressure and body weight of these rats were measured every 4 weeks.At the end of 24 weeks,KATP channel-mediated relaxation responses in the aortas and mesenteric arteries,KATP channel current,and gene expression were examined,respectively.Results:Blood pres-sure and body weight were increased in rats fed with high-fat diet.KATP channel-mediated relaxation responses,currents,and KATP expression in VSMC of both aortas and mesenteric arteries were inhibited in these rats.Conclusion:Altered ATP-sensitive potassium channels in obese rats may underscore obesity-triggered increase in blood pressure.

  1. Arterial pressure changes monitoring with a new precordial noninvasive sensor

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    Faita Francesco

    2008-08-01

    Full Text Available Abstract Background Recently, a cutaneous force-frequency relation recording system based on first heart sound amplitude vibrations has been validated. A further application is the assessment of Second Heart Sound (S2 amplitude variations at increasing heart rates. The aim of this study was to assess the relationship between second heart sound amplitude variations at increasing heart rates and hemodynamic changes. Methods The transcutaneous force sensor was positioned in the precordial region in 146 consecutive patients referred for exercise (n = 99, dipyridamole (n = 41, or pacing stress (n = 6. The curve of S2 peak amplitude variation as a function of heart rate was computed as the increment with respect to the resting value. Results A consistent S2 signal was obtained in all patients. Baseline S2 was 7.2 ± 3.3 mg, increasing to 12.7 ± 7.7 mg at peak stress. S2 percentage increase was + 133 ± 104% in the 99 exercise, + 2 ± 22% in the 41 dipyridamole, and + 31 ± 27% in the 6 pacing patients (p Conclusion S2 recording quantitatively documents systemic pressure changes.

  2. Increased risk of arterial thromboembolic events after Staphylococcus aureus bacteremia

    DEFF Research Database (Denmark)

    Mejer, N; Gotland, N; Uhre, M L;

    2015-01-01

    OBJECTIVES: An association between infection and arterial thromboembolic events (ATE) has been suggested. Here we examined the risk of myocardial infarction (MI), stroke and other ATE after Staphylococcus aureus bacteremia (SAB). METHODS: Danish register-based nation-wide observational cohort study...

  3. Fluid input control in burned patients with the aid of ultrasonic arterial blood pressure monitoring.

    Science.gov (United States)

    Banssillon, V; Latarjet, J

    1975-01-01

    Arterial blood pressure is nowadays easily and reliably measured with ultrasonic equipment. It correlates well with blood volume, and may therefore be used to guide fluid infusion in burned patients. Monitoring of blood pressure, instead of application of old-fashioned recipes, helps to avoid dangerous situations of hypovolemia or overload.

  4. Changes in Doppler waveforms can predict pressure reduction across internal carotid artery stenoses

    DEFF Research Database (Denmark)

    Sillesen, H; Schroeder, T

    1988-01-01

    perfusion pressure. Forty-nine patients were examined consecutively with ultrasound Doppler prior to carotid endarterectomy. Pulsatility index (PI), pulse rise-time (RT), and systolic width (SW) were related to angiographic degree of stenosis and the ratio of distal ICA blood pressure to common carotid...... artery (CCA) blood pressure (ICA/CCA pressure ratio). The latter was determined during surgery. All three waveform parameters were significantly correlated with the ICA/CCA pressure ratio when calculated from the mean frequency curve (p less than 0.001). A reduction in ICA pressure of 20% could...

  5. Low-pressure pulmonary artery aneurysm presenting with pulmonary embolism: a case series

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    Papoulidis Pavlos

    2011-04-01

    Full Text Available Abstract Introduction Pulmonary artery aneurysm is an uncommon disorder with severe complications. The diagnosis is often difficult, since the clinical manifestations are non-specific and the treatment is controversial, as the natural history of the disease is not completely understood. Case presentation We describe the cases of two patients with pulmonary artery aneurysms. The first patient was a 68-year-old Caucasian man with an idiopathic low-pressure pulmonary artery aneurysm together with a pulmonary embolism. The patient preferred a conservative approach and was stable at the 10-month follow-up visit after being placed on anti-coagulant treatment. The second patient was a 66-year-old Caucasian woman with a low-pressure pulmonary artery aneurysm also presented together with a pulmonary embolism. The aneurysm was secondary to pulmonary valve stenosis. She received anti-coagulants and, after stabilization, underwent percutaneous balloon valvuloplasty. Conclusion Pulmonary embolism may be the initial presentation of a low-pressure pulmonary artery aneurysm. No underlying cause for pulmonary embolism was found in either of our patients, suggesting a causal association with low-pressure pulmonary artery aneurysm.

  6. Comparison of how well conscious cats tolerate blood pressure measurement from the radial and coccygeal arteries.

    Science.gov (United States)

    Cannon, Martha J; Brett, Jo

    2012-12-01

    Hypertension is a common condition of older cats and acquiring clinically relevant and repeatable blood pressure (BP) measurements in conscious cats is important in its diagnosis and management. The most common sites for indirect BP measurement in the cat are the radial artery (RA) and the coccygeal artery (CA) but, to date, there are no published data comparing how conscious cats tolerate BP measurements from these sites. A high-definition oscillometric BP monitor was used to measure BP in 30 cats admitted to a cat-only veterinary clinic for reasons other than hypertension. Systolic arterial pressure (SAP), mean arterial pressure (MAP) and diastolic arterial pressure (DAP) were measured using the RA and CA, alternating which site was used first. The number of failed attempts and total time to achieve six measurements was recorded. Measurement of BP using the CA was better tolerated than the RA, resulting in fewer failures and shorter total time required. SAP measurements were slightly higher from the CA compared with the RA, irrespective of which site was used first. There were no significant differences in MAP and DAP. The coccygeal artery appears to be the more appropriate site to use when measuring BP in conscious cats using this oscillometric machine. Further studies are required using alternative BP monitors, including Doppler machines, to establish whether this is a consistent finding. When measuring BP in cats the site used should be recorded and the same site used for all subsequent measurements from the same cat.

  7. Effect of treatment temperature on collagen structures of the decellularized carotid artery using high hydrostatic pressure.

    Science.gov (United States)

    Negishi, Jun; Funamoto, Seiichi; Kimura, Tsuyoshi; Nam, Kwangoo; Higami, Tetsuya; Kishida, Akio

    2011-09-01

    Decellularized tissues have attracted a great deal of attention as regenerating transplantation materials. A decellularizing method based on high hydrostatic pressure (HHP) has been developed, and the preparation of many types of decellularized tissues has been investigated, including aorta, cornea, and dermis. The preparation of a small-diameter vascular graft was studied using a carotid artery from the viewpoint of collagen denaturation and leakage. After HHP, the carotid artery was washed at two washing temperatures (37 and 4°C). Histological evaluation, collagen content measurement and circular dichroism (CD) measurement indicated that the washing temperatures clearly affected the collagen structure of the decellularized carotid artery. The amount of collagen decreased in the carotid artery decellularized by HHP washed at 37°C (HHP/37°C). On the other hand, the amount and structure of collagen were preserved in the carotid artery washed at 4°C after HHP (HHP/4°C). In rat carotid artery syngeneic transplantation, the HHP/37°C decellularized carotid artery occluded after 2 weeks, but the HHP/4°C decellularized one did not. These results indicate that collagen denaturation and leakage of the decellularized carotid artery affect the in vivo performance of the carotid artery.

  8. Opioid receptor antagonists increase [Ca2+]i in rat arterial smooth muscle cells in hemorrhagic shock

    Institute of Scientific and Technical Information of China (English)

    Li KAI; Zhong-feng WANG; Yu-liang SHI; Liang-ming LIU; De-yao HU

    2004-01-01

    AIM: To examine the effects of opioid receptor antagonists and norepinephrine on intracellular free Ca2+ concentration ([Ca2+]i) in mesenteric arterial (MA) smooth muscle cells (SMC) isolated from normal and hemorrhagic shocked rats in the vascular hyporesponse stage. METHODS: The rat model of hemorrhagic shock was made by withdrawing blood to decrease the artery mean blood pressure to 3.73-4.26 kPa and keeping at the level for 3 h.[Ca2+]i of vascular smooth muscle cells (VSMC) were detected by the laser scan confocal microscopy. RESULTS:In the hyporesponse VMSC of rats in hemorrhagic shock, selective δ-, κ-, and μ-opioid receptor antagonists (naltrindole, nor-binaltorphimine, and β-funaltrexamine, 100 nmol/L) as well as norepinephrine 5 μmol/L significantly increased [Ca2+]i by 47 %±13 %, 37 %±14 %, 33 %±10 %, and 54 %±17 %, respectively, although their effects were lower than those in the normal rat cells (the increased values were 148 %±54 %, 130 %±44 %, 63 %±17 %and 110 %±38 %, respectively); and the norepinephrine-induced increase in [Ca2+]i was further augmented by three δ-, κ-, and μ-opioid receptor antagonists (50 nmol/L, respectively) application (from 52 %± 16 % to 99 %±29 %,146 %±54 % and 137 %±47 %, respectively). CONCLUSION: The disorder of [Ca2+]i regulation induced by hemorrhagic shock was mediated by opioid receptor and α-adrenoceptor, which may be partly responsible for the vascular hyporesponse, and the opioid receptor antagonists improved the response of resistance arteries to vascular stimulants in decompensatory stage of hemorrhagic shock.

  9. The blood pressure-induced diameter response of retinal arterioles decreases with increasing diabetic maculopathy

    DEFF Research Database (Denmark)

    Frederiksen, Christian Alcaraz; Jeppesen, Peter; Knudsen, Søren Tang;

    2006-01-01

    were measured using the Retinal Vessel Analyzer (RVA, Imedos, Germany) before, during, and after an increase in the blood pressure induced by isometric exercise. Additionally, the retinal thickness was measured using optical coherence tomography scanning. RESULTS: The arterioles contracted during......BACKGROUND: The aim of the study was to compare the diameter response of retinal arterioles and retinal thickness in patients with different stages of diabetic maculopathy during an increase in the arterial blood pressure. METHODS: Four groups each consisting of 19 individuals were studied. Group...

  10. A computational analysis of the long-term regulation of arterial pressure.

    Science.gov (United States)

    Beard, Daniel A; Pettersen, Klas H; Carlson, Brian E; Omholt, Stig W; Bugenhagen, Scott M

    2013-01-01

    The asserted dominant role of the kidneys in the chronic regulation of blood pressure and in the etiology of hypertension has been debated since the 1970s. At the center of the theory is the observation that the acute relationships between arterial pressure and urine production-the acute pressure-diuresis and pressure-natriuresis curves-physiologically adapt to perturbations in pressure and/or changes in the rate of salt and volume intake. These adaptations, modulated by various interacting neurohumoral mechanisms, result in chronic relationships between water and salt excretion and pressure that are much steeper than the acute relationships. While the view that renal function is the dominant controller of arterial pressure has been supported by computer models of the cardiovascular system known as the "Guyton-Coleman model", no unambiguous description of a computer model capturing chronic adaptation of acute renal function in blood pressure control has been presented. Here, such a model is developed with the goals of: 1. representing the relevant mechanisms in an identifiable mathematical model; 2. identifying model parameters using appropriate data; 3. validating model predictions in comparison to data; and 4. probing hypotheses regarding the long-term control of arterial pressure and the etiology of primary hypertension. The developed model reveals: long-term control of arterial blood pressure is primarily through the baroreflex arc and the renin-angiotensin system; and arterial stiffening provides a sufficient explanation for the etiology of primary hypertension associated with ageing. Furthermore, the model provides the first consistent explanation of the physiological response to chronic stimulation of the baroreflex.

  11. Comparison of noninvasive blood pressure measurement techniques via the coccygeal artery in anesthetized cheetahs (Acinonyx jubatus).

    Science.gov (United States)

    Sadler, Ryan A; Hall, Natalie H; Kass, Philip H; Citino, Scott B

    2013-12-01

    Two indirect blood pressure measurement techniques, Doppler (DOP) sphygmomanometry and oscillometry, applied at the ventral coccygeal artery were compared with simultaneous direct blood pressure measurements at the dorsal pedal artery in 10 anesthetized, captive cheetahs (Acinonyx jubatus). The DOP method was moderately accurate, with relatively little bias (mean difference 3.8 mmHg) and 88.6% of the DOP systolic arterial pressure measurements being within 10 mmHg of the direct systolic arterial measurement. With the oscillometric (OM) method, 89.2% of the mean arterial pressure measurements were within 10 mmHg of the direct measurement and had the least bias (mean difference 2.3 mmHg), 80.7% of the systolic measurements were within 10 mmHg of the direct measurement and had the second least bias (mean difference 2.3 mmHg), and 59% of the diastolic measurements were within 10 mmHg of the direct measurement and had significant bias (mean difference 7.3 mmHg). However, DOP showed relatively poor precision (SD 11.2 mmHg) compared with OM systolic (SD 8.0 mmHg), diastolic (SD 8.6 mmHg), and mean (SD 5.7 mmHg). Both techniques showed a linear relationship with the direct technique measurements over a wide range of blood pressures. The DOP method tended to underestimate systolic measurements below 160 mmHg and overestimate systolic measurements above 160 mmHg. The OM method tended to underestimate mean pressures below 160 mm Hg, overestimate mean pressures above 160 mmHg, underestimate systolic pressures below 170 mmHg, overestimate systolic pressures above 170 mmHg, and underestimate diastolic pressures throughout the measured blood pressure range. Indirect blood pressure measurement using the ventral coccygeal artery, particularly when using an OM device for mean and systolic arterial pressure, may be useful in the clinical assessment of cheetahs when monitoring trends over time, but caution should be taken when interpreting individual values.

  12. Membrane potential and Ca2+ concentration dependence on pressure and vasoactive agents in arterial smooth muscle: A model.

    Science.gov (United States)

    Karlin, Arthur

    2015-07-01

    Arterial smooth muscle (SM) cells respond autonomously to changes in intravascular pressure, adjusting tension to maintain vessel diameter. The values of membrane potential (Vm) and sarcoplasmic Ca(2+) concentration (Ca(in)) within minutes of a change in pressure are the results of two opposing pathways, both of which use Ca(2+) as a signal. This works because the two Ca(2+)-signaling pathways are confined to distinct microdomains in which the Ca(2+) concentrations needed to activate key channels are transiently higher than Ca(in). A mathematical model of an isolated arterial SM cell is presented that incorporates the two types of microdomains. The first type consists of junctions between cisternae of the peripheral sarcoplasmic reticulum (SR), containing ryanodine receptors (RyRs), and the sarcolemma, containing voltage- and Ca(2+)-activated K(+) (BK) channels. These junctional microdomains promote hyperpolarization, reduced Ca(in), and relaxation. The second type is postulated to form around stretch-activated nonspecific cation channels and neighboring Ca(2+)-activated Cl(-) channels, and promotes the opposite (depolarization, increased Ca(in), and contraction). The model includes three additional compartments: the sarcoplasm, the central SR lumen, and the peripheral SR lumen. It incorporates 37 protein components. In addition to pressure, the model accommodates inputs of α- and β-adrenergic agonists, ATP, 11,12-epoxyeicosatrienoic acid, and nitric oxide (NO). The parameters of the equations were adjusted to obtain a close fit to reported Vm and Ca(in) as functions of pressure, which have been determined in cerebral arteries. The simulations were insensitive to ± 10% changes in most of the parameters. The model also simulated the effects of inhibiting RyR, BK, or voltage-activated Ca(2+) channels on Vm and Ca(in). Deletion of BK β1 subunits is known to increase arterial-SM tension. In the model, deletion of β1 raised Ca(in) at all pressures, and these

  13. Comparison of two methods of dental prophylaxis: evaluation of arterial pressure and patient comfort in a clinical randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Camila Lopes FERREIRA

    Full Text Available Abstract Introduction The number of hypertensive patients is increasing and prophylaxis with bicarbonate jet are widely performed in clinical practice using large amounts of this substance in a short period of time, which may lead to increased arterial pressure. In the literature there are several studies that analyze the effect of sodium bicarbonate jet on the biofilm and dental structures, but not report the effect on arterial pressure. Aim Evaluated the change in arterial pressure before and after two procedures of dental prophylaxis, jet baking soda application and conventional prophylaxis, and patient opinion of the comfort of each system was obtained. Material and method We selected 20 patients aged 18 to 30 in need of prophylaxis to remove biofilm. The patients were placed into three different treatment groups: sodium bicarbonate jet (G1, conventional prophylaxis (G2 and control (G3, with a one month interval between treatments. Patients were divided into groups randomly. Measurements were performed immediately before and after the procedure, 15 and 30 minutes after the end of treatment. Patient comfort was measured using a Visual Analog Scale (VAS at the end of each treatment. Data were analyzed by analysis of variance. Result There was a statistically significant difference in the comfort of the procedures, with G2 and G3 being better than G1. Additionally, an increase in the diastolic blood pressure was observed in sodium bicarbonate jet group evaluated just after the procedure. Conclusion The conventional prophylaxis is more comfortable from the patient stand point and does not alter arterial pressure.

  14. Measurement of Blood Pressure Using an Arterial Pulsimeter Equipped with a Hall Device

    Directory of Open Access Journals (Sweden)

    Jong-Gu Choi

    2011-01-01

    Full Text Available To measure precise blood pressure (BP and pulse rate without using a cuff, we have developed an arterial pulsimeter consisting of a small, portable apparatus incorporating a Hall device. Regression analysis of the pulse wave measured during testing of the arterial pulsimeter was conducted using two equations of the BP algorithm. The estimated values of BP obtained by the cuffless arterial pulsimeter over 5 s were compared with values obtained using electronic or liquid mercury BP meters. The standard deviation between the estimated values and the measured values for systolic and diastolic BP were 8.3 and 4.9, respectively, which are close to the range of values of the BP International Standard. Detailed analysis of the pulse wave measured by the cuffless radial artery pulsimeter by detecting changes in the magnetic field can be used to develop a new diagnostic algorithm for BP, which can be applied to new medical apparatus such as the radial artery pulsimeter.

  15. Obese children and adolescents have elevated nighttime blood pressure independent of insulin resistance and arterial stiffness

    DEFF Research Database (Denmark)

    Hvidt, Kristian N; Olsen, Michael H; Holm, Jens-Christian

    2014-01-01

    BACKGROUND: Insulin resistance has been related to elevated blood pressure (BP) in obese children and may adversely affect the vasculature by arterial stiffening. The objective was to investigate whether daytime and nighttime BP were elevated and related to insulin resistance and arterial stiffness...... in obese children and adolescents. METHODS: Ninety-two obese patients aged 10-18 years were compared with 49 healthy control individuals. Insulin resistance was measured as the homeostatic assessment model (HOMA), and arterial stiffness was measured as carotid-femoral pulse wave velocity (cfPWV). RESULTS...... analyses, the higher nighttime BP in the obese group was independent of logHOMA and cfPWV. CONCLUSIONS: Obese children had a higher nighttime BP when compared with the control group independently of insulin resistance and arterial stiffness. No relationship was found between insulin resistance and arterial...

  16. Ratio of exercise and recovery systolic blood pressure integrals in prediction of coronary artery disease

    Directory of Open Access Journals (Sweden)

    Jure Mirat

    2009-02-01

    Full Text Available Aim This study was performed to determine whether the ratio (Q =A/B of area A under the curve of exercise systolic blood pressure(SBP increase and area B under curve of recovery SBP decreaseis predictive of angiographic coronary artery disease (CAD.Methods Patients who performed exercise testing and subsequentlyunderwent coronary angiography, within three months, wereanalyzed in this study. According to angiographic report, patientswere divided in three groups: without disease or with stenosis lessthan 50% (group 1, significant (group 2, and severe (group 3.Severe disease was defined as left main, three-vessel or two-vesseldisease with involvement of proximal left anterior descending artery.Results There were 137 patients included in this study (age 59 ±10, 70% male. Group 1 included 57%, group 2 included 30%,and group 3 included 13% of patients. Mean values of the Q ratiowere 2.72 ± 0.9, 1.74 ± 0.76, 1.01 ± 0.38 in groups 1, 2 and 3,respectively. By means of robust discrimination analysis, statisticallysignificant difference between groups 1, 2 and 3 in values ofthe ratio Q (p < 0.001 was found.Conclusion The ratio of exercise SBP increase and recovery SBPdecrease areas under the curve suggests severity of CAD.

  17. Continuous Non-Invasive Arterial Pressure Technique Improves Patient Monitoring during Interventional Endoscopy

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    Sylvia Siebig, Felix Rockmann, Karl Sabel, Ina Zuber-Jerger, Christine Dierkes, Tanja Brünnler, Christian E. Wrede

    2009-01-01

    Full Text Available Introduction: Close monitoring of arterial blood pressure (BP is a central part of cardiovascular surveillance of patients at risk for hypotension. Therefore, patients undergoing diagnostic and therapeutic procedures with the use of sedating agents are monitored by discontinuous non-invasive BP measurement (NIBP. Continuous non-invasive BP monitoring based on vascular unloading technique (CNAP®, CN Systems, Graz may improve patient safety in those settings. We investigated if this new technique improved monitoring of patients undergoing interventional endoscopy. Methods: 40 patients undergoing interventional endoscopy between April and December 2007 were prospectively studied with CNAP® in addition to standard monitoring (NIBP, ECG and oxygen saturation. All monitoring values were extracted from the surveillance network at one-second intervals, and clinical parameters were documented. The variance of CNAP® values were calculated for every interval between two NIBP measurements. Results: 2660 minutes of monitoring were recorded (mean 60.1±34.4 min/patient. All patients were analgosedated with midazolam and pethidine, and 24/40 had propofol infusion (mean 90.9±70.3 mg. The mean arterial pressure for CNAP® was 102.4±21.2 mmHg and 106.8±24.8 mmHg for NIBP. Based on the first NIBP value in an interval between two NIBP measurements, BP values determined by CNAP® showed a maximum increase of 30.8±21.7% and a maximum decrease of 22.4±28.3% (mean of all intervals. Discussion: Conventional intermittent blood pressure monitoring of patients receiving sedating agents failed to detect fast changes in BP. The new technique CNAP® improved the detection of rapid BP changes, and may contribute to a better patient safety for those undergoing interventional procedures.

  18. Role of pressor mechanisms from the NTS and CVLM in control of arterial pressure.

    Science.gov (United States)

    Moreira, Thiago Santos; Sato, Monica Akemi; Takakura, Ana Carolina Thomaz; Menani, José Vanderlei; Colombari, Eduardo

    2005-11-01

    In the present study, we investigated the effects of inhibition of the caudal ventrolateral medulla (CVLM) with the GABA(A) agonist muscimol combined with the blockade of glutamatergic mechanism in the nucleus of the solitary tract (NTS) with kynurenic acid (kyn) on mean arterial pressure (MAP), heart rate (HR), and regional vascular resistances. In male Holtzman rats anesthetized intravenously with urethane/chloralose, bilateral injections of muscimol (120 pmol) into the CVLM or bilateral injections of kyn (2.7 nmol) into the NTS alone increased MAP to 186 +/- 11 and to 142 +/- 6 mmHg, respectively, vs. control: 105 +/- 4 mmHg; HR to 407 +/- 15 and to 412 +/- 18 beats per minute (bpm), respectively, vs. control: 352 +/- 12 bpm; and renal, mesenteric and hindquarter vascular resistances. However, in rats with the CVLM bilaterally blocked by muscimol, additional injections of kyn into the NTS reduced MAP to 88 +/- 5 mmHg and mesenteric and hindquarter vascular resistances below control baseline levels. Moreover, in rats with the glutamatergic mechanisms of the NTS blocked by bilateral injections of kyn, additional injections of muscimol into the CVLM also reduced MAP to 92 +/- 2 mmHg and mesenteric and hindquarter vascular resistances below control baseline levels. Simultaneous blockade of NTS and CVLM did not modify the increase in HR but also abolished the increase in renal vascular resistance produced by each treatment alone. The results suggest that important pressor mechanisms arise from the NTS and CVLM to control vascular resistance and arterial pressure under the conditions of the present study.

  19. HISTOLOGICAL STUDY OF MEDIUM SIZED ARTERIES OF NECK IN RELATION WITH THEIR PULSE PRESSURE AND PULSATORY POWER

    Directory of Open Access Journals (Sweden)

    Prerana

    2014-11-01

    Full Text Available : INTRODUCTION: There are several studies on the microstructure of main arteries of the body but limited have been dealt with the neck arteries. It has been mentioned that the vascular pathologies like the thrombo-embolism, atherosclerosis and infarction are common in the branches of vertebral and internal carotid artery as compared to the branches of external carotid artery. OBJECTIVE: To study the histological structure of the 3 medium sized arteries of neck namely external carotid, internal carotid and vertebral artery, calculation of their mean pulse pressure and pulsatory power and to find any association between them if present. METHOD: Fresh samples of external carotid, internal carotid and vertebral artery each measuring 10mm in length were taken from five cadavers and prepared for histological examination under microscope using orcein and H&E stain. The mean pressure and pulsatory power of these arteries were calculated by taking the measurements such as wall thickness, lumen circumference, arterial wall area, and smooth muscle fibre density in tunica media in that arterial segment. RESULT: The pulsatory power of external carotid artery, internal carotid artery and vertebral artery is found to be 120, 273.3, 400 Joules /heart beat and the mean pressure is 17.1 mm Hg, 27.3 mm Hg and 33.3 mm Hg respectively. CONCLUSION: The thickness of tunica media of an artery is directly proportional to its pulsatory power. The mean pulse pressure, pulsatory power as well the number of smooth muscles fibres in tunica media are more in internal carotid artery and vertebral artery in comparison to external carotid artery. It may be a very important reason why vascular pathologies are less common in branches of external carotid as compare to internal carotid and vertebral artery.

  20. A simple model of cerebral blood flow dependence on arterial blood pressure

    CERN Document Server

    Gersten, Alexander

    2011-01-01

    It is shown that the dependence of the cerebral blood flow (CBF) on mean arterial blood pressure (MABP) can be described with a simple model having the following assumptions. Below certain MABP (denoted as MABP1) there are no autoregulatory or feedback mechanisms influencing CBF. Between MABP1 and MABP2 (MABP at which breakthrough accurs) there is a linear (on MABP) dependent feedback with a sloap depending very much on the individual considered. The classical autoregulation model with a plateau in between MABP1 and MABP2 is a particular case of this model. The model describes well the experiments performed on dogs (Harper 1966), for which the individual feedback sloap parameter varied to great extent, indicating the importance of mesurments on individuals against averaged mesurments (or measurments on diffent individuals) which superficially support the classical autoregulation. New effect of decreased CBF, while increasing MABP, was observed.

  1. The giraffe kidney tolerates high arterial blood pressure by high renal interstitial pressure and low glomerular filtration rate

    DEFF Research Database (Denmark)

    Damkjær, Mads; Wang, T; Brøndum, E

    2015-01-01

    BACKGROUND: The tallest animal on earth, the giraffe (Giraffa camelopardalis) is endowed with a mean arterial blood pressure (MAP) twice that of other mammals. The kidneys reside at heart level and show no sign of hypertension-related damage. We hypothesized that a species-specific evolutionary...... on body mass. A strong renal capsule supports a RIHP, which is >10-fold that of other mammals effectively reducing the net filtration pressure and protecting against the high MAP....... renal plasma flow (ERPF). Renal interstitial hydrostatic pressure (RIHP) was assessed by inserting a needle into the medullary parenchyma. Doppler ultrasound measurements provided renal artery resistive index (RI). Hormone concentrations as well as biomechanical, structural and histological...

  2. Increased rate of arterial stiffening with obesity in adolescents: a five-year follow-up study.

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    Frida Dangardt

    Full Text Available BACKGROUND: We prospectively and longitudinally determined the effects of childhood obesity on arterial stiffening and vascular wall changes. Changes in arterial stiffness measured as pulse wave velocity (PWV and vascular morphology of the radial (RA and dorsal pedal arteries (DPA were examined in obese adolescents compared to lean subjects in a 5-year follow-up study. METHODOLOGY/PRINCIPAL FINDINGS: A total of 28 obese subjects and 14 lean controls participated in both baseline (14 years old and follow-up studies. PWV was measured by tonometer (SphygmoCor® and recorded at RA and carotid artery, respectively. Intima thickness (IT, intima-media thickness (IMT and RA and DPA diameters were measured using high-resolution ultrasound (Vevo 770™. Over the course of 5 years, PWV increased by 25% in the obese subjects as compared to 3% in the controls (p = 0.01. Diastolic blood pressure (DBP increased by 23% in the obese subjects as opposed to 6% in controls (p = 0.009. BMI increased similarly in both groups, as did the IT and IMT. The change in PWV was strongly associated to the baseline BMI z -score (r = 0.51, p<0.001, as was the change in DBP (r = 0.50, p = 0.001. CONCLUSIONS/SIGNIFICANCE: During the transition from early to late adolescence, there was a general increase in arterial stiffness, which was aggravated by childhood obesity. The increase in arterial stiffness and DBP after 5 years was closely correlated to the baseline BMI z -score, indicating that childhood obesity has an adverse impact on vascular adaptation.

  3. Effects of Weather and Heliophysical Conditions on Emergency Ambulance Calls for Elevated Arterial Blood Pressure

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    Jone Vencloviene

    2015-02-01

    Full Text Available We hypothesized that weather and space weather conditions were associated with the exacerbation of essential hypertension. The study was conducted during 2009–2010 in the city of Kaunas, Lithuania. We analyzed 13,475 cards from emergency ambulance calls (EACs, in which the conditions for the emergency calls were made coded I.10–I.15. The Kaunas Weather Station provided daily records of air temperature (T, wind speed (WS, relative humidity, and barometric pressure (BP. We evaluated the associations between daily weather variables and daily number of EACs by applying a multivariate Poisson regression. Unfavorable heliophysical conditions (two days after the active-stormy geomagnetic field or the days with solar WS > 600 km/s increased the daily number of elevated arterial blood pressure (EABP by 12% (RR = 1.12; 95% confidence interval (CI 1.04–1.21; and WS ≥ 3.5 knots during days of T < 1.5 °C and T ≥ 12.5 °C by 8% (RR = 1.08; CI 1.04–1.12. An increase of T by 10 °C and an elevation of BP two days after by 10 hPa were associated with a decrease in RR by 3%. An additional effect of T was detected during days of T ≥ 17.5 °C only in females. Women and patients with grade III arterial hypertension at the time of the ambulance call were more sensitive to weather conditions. These results may help in the understanding of the population’s sensitivity to different weather conditions.

  4. Retrograde arterial leg blood flow during tilt-back from a head-up posture: importance of capacitive flows when arterial pressure changes.

    Science.gov (United States)

    Sheriff, Don D; Nådland, Inger Helene; Toska, Karin

    2010-03-01

    The windkessel function of the arterial system converts the intermittent action of the heart into more continuous microcirculatory blood flow during diastole via the return of elastic energy stored in the walls of the arteries during systole. Might the same phenomenon occur regionally within the arterial system during tilting owing to regional differences in local arterial pressure imposed by gravity? We sought to test the hypothesis that during tilt-back from a head-up posture, the return of stored elastic energy in leg arteries would work to slow, or perhaps transiently reverse, the flow of blood in the femoral artery. Femoral artery blood flow and arterial pressure were recorded during tilt back from a 30 degrees head-up posture to supine (approximately 0.5 G) in young, healthy subjects (n = 7 males and 3 females) before and during clonidine infusion. During control (no drug) conditions femoral artery blood flow ceased for an entire heart beat during tilt-back. During clonidine infusion femoral artery blood flow reversed for at least one entire heart beat during tilt-back, i.e., blood flow in the retrograde direction in the femoral artery from the leg into the abdomen. Thus substantial capacitive effects of tilting on leg blood flow occur in humans during mild changes in posture.

  5. On the reliability of frequency components in systolic arterial pressure in patients with atrial fibrillation.

    Science.gov (United States)

    Corino, Valentina D A; Lombardi, Federico; Mainardi, Luca T

    2010-04-01

    Atrial fibrillation (AF) is characterized by desynchronization of atrial electrical activity causing a consequent irregular ventricular response. In AF, the beat-to-beat variation of blood pressure is increased because of variations in filling time and contractility. However, only a few studies have analyzed short-term blood pressure variations in AF, and we have recently observed a harmonic low-frequency (LF) component in systolic arterial pressure (SAP) during AF. Aim of the present study is to propose a method to verify the reliability of the spectral component found in SAP series, based on the position of the poles of the autoregressive spectral decomposition in the z-plane. In particular, 1,000 random permutations of the series allowed the definition of an area in the z-plane where poles from random process are likely to occur. Poles lying outside this area are considered as reliable oscillations. We tested the method on 53 recordings obtained at rest from patients with persistent AF. LF component was found in, respectively, 51 and 43 recordings in SAP and RR series. High-frequency (HF) component was found in all the recordings for both SAP and RR series. Using the proposed test, the percentage of reliable components in LF and HF bands was 80 and 38 in SAP series, and 20 and 18 in RR series. We concluded that, at variance with RR ones, SAP LF components are likely to represent true physiological oscillations.

  6. Association of vitamin D status with arterial blood pressure and hypertension risk

    DEFF Research Database (Denmark)

    Vimaleswaran, Karani S; Cavadino, Alana; Berry, Diane J

    2014-01-01

    BACKGROUND: Low plasma 25-hydroxyvitamin D (25[OH]D) concentration is associated with high arterial blood pressure and hypertension risk, but whether this association is causal is unknown. We used a mendelian randomisation approach to test whether 25(OH)D concentration is causally associated...... with blood pressure and hypertension risk. METHODS: In this mendelian randomisation study, we generated an allele score (25[OH]D synthesis score) based on variants of genes that affect 25(OH)D synthesis or substrate availability (CYP2R1 and DHCR7), which we used as a proxy for 25(OH)D concentration. We meta......, -0·12 mm Hg, 95% CI -0·20 to -0·04; p=0·003) and reduced odds of hypertension (odds ratio [OR] 0·98, 95% CI 0·97-0·99; p=0·0003), but not with decreased diastolic blood pressure (β per 10% increase, -0·02 mm Hg, -0·08 to 0·03; p=0·37). In meta-analyses in which we combined data from D...

  7. Mean arterial pressure change associated with cerebral blood flow in healthy older adults.

    Science.gov (United States)

    Deverdun, Jeremy; Akbaraly, Tasnime N; Charroud, Celine; Abdennour, Meriem; Brickman, Adam M; Chemouny, Stephane; Steffener, Jason; Portet, Florence; Bonafe, Alain; Stern, Yaakov; Ritchie, Karen; Molino, François; Le Bars, Emmanuelle; Menjot de Champfleur, Nicolas

    2016-10-01

    We investigate over a 12-year period the association between regional cerebral blood flow (CBF) and cardiovascular risk factors in a prospective cohort of healthy older adults (81.96 ± 3.82 year-old) from the Cognitive REServe and Clinical ENDOphenotype (CRESCENDO) study. Cardiovascular risk factors were measured over 12 years, and gray matter CBF was measured at the end of the study from high-resolution magnetic resonance imaging using arterial spin labeling. The association between cardiovascular risk factors, their long-term change, and CBF was assessed using multivariate linear regression models. Women were observed to have higher CBF than men (p < 0.05). Increased mean arterial pressure (MAP) over the 12-year period was correlated with a low cerebral blood flow (p < 0.05, R(2) = 0.21), whereas no association was detected between CBF and MAP at the time of imaging. High levels of glycemia tended to be associated with low cerebral blood flow values (p < 0.05). Age, alcohol consumption, smoking status, body mass index, history of cardiovascular disease, and hypertension were not associated with CBF. Our main result suggests that change in MAP is the most significant predictor of future CBF in older adults.

  8. Increased arterial inflammation in individuals with stage 3 chronic kidney disease

    Energy Technology Data Exchange (ETDEWEB)

    Takx, Richard A.P. [Massachusetts General Hospital and Harvard Medical School, Cardiac MR PET CT Program, Boston, MA (United States); University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); MacNabb, Megan H.; Emami, Hamed; Abdelbaky, Amr; Lavender, Zachary R. [Massachusetts General Hospital and Harvard Medical School, Cardiac MR PET CT Program, Boston, MA (United States); Singh, Parmanand [Massachusetts General Hospital and Harvard Medical School, Cardiac MR PET CT Program, Boston, MA (United States); New York Presbyterian Hospital, Weill Cornell Medical College, Division of Cardiology, New York, NY (United States); Di Carli, Marcelo; Taqueti, Viviany; Foster, Courtney [Brigham and Women' s Hospital and Harvard Medical School, Division of Radiology, Department of Medicine, Boston, MA (United States); Mann, Jessica; Comley, Robert A.; Weber, Chek Ing Kiu [F. Hoffmann-La Roche Ltd., Basel (Switzerland); Tawakol, Ahmed [Massachusetts General Hospital and Harvard Medical School, Cardiac MR PET CT Program, Boston, MA (United States); Massachusetts General Hospital and Harvard Medical School, Cardiology Division, Boston, MA (United States); Massachusetts General Hospital, Boston, MA (United States)

    2016-02-15

    While it is well known that patients with chronic kidney disease (CKD) are at increased risk for the development and progression of atherosclerosis, it is not known whether arterial inflammation is increased in mild CKD. The aim of this study was to compare arterial inflammation using {sup 18}F-FDG PET/CT in patients with CKD and in matched controls. This retrospective study included 128 patients undergoing FDG PET/CT imaging for clinical indications, comprising 64 patients with stage 3 CKD and 64 control patients matched by age, gender, and cancer history. CKD was defined according to guidelines using a calculated glomerular filtration rate (eGFR). Arterial inflammation was measured in the ascending aorta as FDG uptake on PET. Background FDG uptake (venous, subcutaneous fat and muscle) were recorded. Coronary artery calcification (CAC) was assessed using the CT images. The impact of CKD on arterial inflammation and CAC was then assessed. Arterial inflammation was higher in patients with CKD than in matched controls (standardized uptake value, SUV: 2.41 ± 0.49 vs. 2.16 ± 0.43; p = 0.002). Arterial SUV correlated inversely with eGFR (r = -0.299, p = 0.001). Venous SUV was also significantly elevated in patients with CKD, while subcutaneous fat and muscle tissue SUVs did not differ between groups. Moreover, arterial SUV remained significantly elevated in patients with CKD compared to controls after correcting for muscle and fat background, and also remained significant after adjusting for clinical risk factors. Further, CKD was associated with arterial inflammation (SUV) independent of the presence of subclinical atherosclerosis (CAC). Moderate CKD is associated with increased arterial inflammation beyond that of controls. Further, the increased arterial inflammation is independent of presence of subclinical atherosclerosis. Current risk stratification tools may underestimate the presence of atherosclerosis in patients with CKD and thereby the risk of

  9. Evaluation of restenosis, renal function and blood pressure after the renal artery stenting in patients with atherosclerosis renovascular disease

    Institute of Scientific and Technical Information of China (English)

    王焱

    2006-01-01

    Objective To evaluate the restenosis, renal function and blood pressure after renal artery stenting in patients with atherosclerosis renovascular disease. Methods Percutaneous renal artery stent (PTRAS) was performed in 135 patients with single or bilateral renal artery stenosis (≥70%). Clinical data of above patients were studied during follow-up period. Results A total of 147

  10. Results of ambulatory arterial blood pressure monitoring in children with obesity

    Directory of Open Access Journals (Sweden)

    Faruk Öktem

    2010-12-01

    Full Text Available Objectives: The relationship between obesity and essential hypertension is well known. In this study, we aimed to evaluate ambulatory arterial blood pressure monitoring of obese and non-obese children who had similar demographic characteristics.Materials and methods: Seventy one children and adolescents (n=39 obesity, n=32 controls were studied. Blood pressure of the children were measured by 24 hour ambulatory blood pressure monitoring device.Results: Obese children had significantly higher mean blood pressure values (systolic 121.9±11.7 mmHg, diastolic 70.2±5.3 mmHg than control subjects (systolic 109.3±6.7 mmHg, diastolic 65.1±4.6 mmHg, p0.05. Blood pressure load was found to be increased in obese children compared to the controls (%13.6±12.9 and %2.6±3.4, respectively; p<0.05. Serum total cholesterol and LDL-cholesterol levels of obese children (181.1±33.4 and 131.1±23.1mg/dl were significantly higher than those of the controls (134.3±11.1 and 103.3±14.2 mg/dl, p<0.05.Conclusions: Obesity in children and adolescents should not be regarded as variations of normality, but as abnormality with an extremely high risk for the development of hypertension and hyperlipidemia in adulthood.

  11. Energy harvesting from arterial blood pressure for powering embedded brain sensors

    Science.gov (United States)

    Nanda, Aditya; Karami, M. Amin

    2016-04-01

    This paper investigates energy harvesting from arterial blood pressure via the piezoelectric effect by using a novel streaked cylinder geometry for the purpose of powering embedded micro-sensors in the brain. Initially, we look at the energy harvested by a piezoelectric cylinder placed inside an artery acted upon by blood pressure. Such an arrangement would be tantamount to constructing a stent out of piezoelectric materials. A stent is a cylinder placed in veins and arteries to prevent obstruction in blood flow. The governing equations of a conductor coated piezoelectric cylinder are obtained using Hamilton's principle. Pressure acting in arteries is radially directed and this is used to simplify the modal analysis and obtain the transfer function relating pressure to the induced voltage across the surface of the harvester. The power harvested by the cylindrical harvester is obtained for different shunt resistances. Radially directed pressure occurs elsewhere and we also look at harvesting energy from oil flow in pipelines. Although the energy harvested by the cylindrical energy harvester is significant at resonance, the natural frequency of the system is found to be very high. To decrease the natural frequency, we propose a novel streaked stent design by cutting it along the length, transforming it to a curved plate and decreasing the natural frequency. The governing equations corresponding to the new geometry are derived using Hamilton's principle and modal analysis is used to obtain the transfer function.

  12. Use of paravascular admittance waveforms to monitor relative change in arterial blood pressure

    Science.gov (United States)

    Zielinski, Todd M.; Hettrick, Doug; Cho, Yong

    2010-04-01

    Non-invasive methods to monitor ambulatory blood pressure often have limitations that can affect measurement accuracy and patient adherence [1]. Minimally invasive measurement of a relative blood pressure surrogate with an implantable device may provide a useful chronic diagnostic and monitoring tool. We assessed a technique that uses electrocardiogram and paravascular admittance waveform morphology analysis to one, measure a time duration (vascular tone index, VTI in milliseconds) change from the electrocardiogram R-wave to admittance waveform peak and two, measure the admittance waveform minimum, maximum and magnitude as indicators of change in arterial compliance/distensibility or pulse pressure secondary to change in afterload. Methods: Five anesthetized domestic pigs (32 ± 4.2 kg) were used to study the effects of phenylephrine (1-5 ug/kg/min) on femoral artery pressure and admittance waveform morphology measured with a quadrapolar electrode array catheter placed next to the femoral artery to assess the relative change in arterial compliance due to change in peripheral vascular tone. Results: Statistical difference was observed (p blood pressure may be suitable for implantable devices to detect progression of cardiovascular disease such as hypertension.

  13. Strophanthus hispidus attenuates the Ischemia-Reperfusion induced myocardial Infarction and reduces mean arterial pressure in renal artery occlusion

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    Rohit Gundamaraju

    2014-01-01

    Full Text Available Background: The myocardium is generally injured in the case of reperfusion injury and arterial damage is caused by hypertension. In reference to these statements, the present study was focused. Cardiac glycosides were said to have protective effects against myocardial infarction and hypertension. Strophanthus hispidus was thus incorporated in the study. Objective: The prime objective of the study was to investigate the protective effects of Strophanthus hispidus against ischemia-reperfusion myocardial Infarction and renal artery occluded hypertension in rats. Materials and Methods: The animal model adopted was surgically-induced myocardial ischemia, performed by means of left anterior descending coronary artery occlusion (LAD for 30 min followed by reperfusion for another 4 h. Infarct size was assessed by using the staining agent TTC (2,3,5-triphenyl tetrazolium chloride. Hypertension was induced by clamping the renal artery with renal bulldog clamp for 4 h. Results: The study was fruitful by the effect of Strophanthus hispidus on infarction size, which got reduced to 27.2 ± 0.5and 20.0 ± 0.2 by 500 mg/Kg and 1000 mg/Kg ethanolic extracts which was remarkably significant when compared with that of the control group 52.8 ± 4.6. The plant extract did reduce heart rate at various time intervals. There was also a protective effect in the case of mean arterial blood pressure were the 500 mg/Kg and 1000 mg/Kg of the plant extract did reduce the hypertension after 60 minutes was 60.0 ± 4.80 and 50.50 ± 6.80. Conclusion: The results suggest that 500 mg/Kg and 100 mg/Kg ethanolic extract of Strophanthus hispidus was found to possess significant cardiac protective and anti-hypertensive activity.

  14. Association of thyroid function with arterial pressure in normotensive and hypertensive euthyroid individuals: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Saltiki Katerina

    2008-09-01

    Full Text Available Abstract Background Overt hypothyroidism has been associated with arterial hypertension and increased arterial stiffness. Results in euthyroid individuals have been conflicting. We investigated associations of thyroid function with systolic (SAP and diastolic (DAP arterial pressure in euthyroid subjects. Methods 311 euthyroid individuals (185 women, mean age 43.9 ± 9 without a history of diabetes attending a preventive medicine program were examined. Subjects receiving thyroxine (10.6% were excluded; 19.3% had hypertension, 43% had a family history for hypertension. TSH, fT4, thyroid autoantibodies, insulin, glucose were measured. The "fT4.TSH product", which has been suggested as a T4 resistance-index, was calculated. Results TSH range was 0.1–8, median 1.4 mU/L, fT4 range was 11.5–25.2 pmol/L, median 17.4. TSH and the "fT4.TSH product" were positively associated with DAP (p 2 mU/L (35.3% vs 21.3%, p = 0.045. Conclusion In euthyroid individuals the association of thyroid function with diastolic arterial pressure remains significant even when a stricter "normal range" for TSH levels is considered. The "freeT4.TSH" product appears to be an even stronger predictor of DAP, independently of HOMA insulin resistance index and obesity.

  15. Acute effects of supramaximal exercise on carotid artery compliance and pulse pressure in young men and women.

    Science.gov (United States)

    Rossow, Lindy; Fahs, Christopher A; Guerra, Myriam; Jae, Sae Young; Heffernan, Kevin S; Fernhall, Bo

    2010-11-01

    The purpose of this study was to determine the cumulative effects of repeated cycling sprints (Wingate tests) on carotid compliance and blood pressure (BP). Fourteen young, healthy men and women completed this study. Vascular and hemodynamic measurements were taken at rest, 5 min following a first Wingate test, 25 min following the first Wingate test, 5 min following a second Wingate test, and 25 min following the second Wingate test. At each time point, the measurements taken included brachial and carotid pulse pressure (PP), heart rate, carotid artery maximum and minimum diameters, and carotid compliance. Carotid BP was obtained with applanation tonometry. Carotid diameters were obtained using ultrasonography and compliance was calculated from carotid diameters and BP. Carotid and brachial PP increased significantly (P sprint, carotid arterial compliance decreased significantly more than 5 min following the first sprint (P sprint reduces carotid artery compliance immediately after exercise. Performance of a second identical cycling sprint further compounds this vascular change, reducing carotid artery compliance beyond levels seen following a single cycling sprint.

  16. Aerobic exercise training increases plasma Klotho levels and reduces arterial stiffness in postmenopausal women.

    Science.gov (United States)

    Matsubara, Tomoko; Miyaki, Asako; Akazawa, Nobuhiko; Choi, Youngju; Ra, Song-Gyu; Tanahashi, Koichiro; Kumagai, Hiroshi; Oikawa, Satoshi; Maeda, Seiji

    2014-02-01

    The Klotho gene is a suppressor of the aging phenomena, and the secretion as well as the circulation of Klotho proteins decrease with aging. Although habitual exercise has antiaging effects (e.g., a decrease in arterial stiffness), the relationship between Klotho and habitual exercise remains unclear. In the present study, we investigated the effect of habitual exercise on Klotho, with a particular focus on arterial stiffness. First, we examined the correlation between plasma Klotho concentration and arterial stiffness (carotid artery compliance and β-stiffness index) or aerobic exercise capacity [oxygen uptake at ventilatory threshold (VT)] in 69 healthy, postmenopausal women (50-76 years old) by conducting a cross-sectional study. Second, we tested the effects of aerobic exercise training on plasma Klotho concentrations and arterial stiffness. A total of 19 healthy, postmenopausal women (50-76 years old) were divided into two groups: control group and exercise group. The exercise group completed 12 wk of moderate aerobic exercise training. In the cross-sectional study, plasma Klotho concentrations positively correlated with carotid artery compliance and VT and negatively correlated with the β-stiffness index. In the interventional study, aerobic exercise training increased plasma Klotho concentrations and carotid artery compliance and decreased the β-stiffness index. Moreover, the changes in plasma Klotho concentration and arterial stiffness were found to be correlated. These results suggest a possible role for secreted Klotho in the exercise-induced modulation of arterial stiffness.

  17. Hematocrit and mean arterial blood pressure in pre- and postmenopause women

    Directory of Open Access Journals (Sweden)

    Beatriz Y Salazar Vázquez

    2009-05-01

    Full Text Available Beatriz Y Salazar Vázquez1,2, Miguel A Salazar Vázquez3,4, Marcos Intaglietta2, Ulf de Faire5, Bengt Fagrell6, Pedro Cabrales21Facultad de Medicina, 3Department of Physical Chemistry, Universidad Juárez del estado de Durango, Durango, México; 2Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA; 4Department of Pediatrics, Instituto Mexicano del Seguro Social, Durango, México; 5Division of Cardiovascular Epidemiology, Institute of Environmental Medicine, Department of Cardiology, Karolinska Institutet, Solna, Stockholm, Sweden; 6Department of Medicine, Karolinska Institutet at Karolinska Hospital, Solna, Stockholm, SwedenAbstract: The relationship between mean arterial blood pressure (MAP and hematocrit (Hct was studied in pre- and postmenopause women in the city of Durango, Mexico. Premenopause women show a negative trend between parameters that is not statistically significant. MAP and Hct are directly related in postmenopause women (p < 0.01. It is proposed that that this MAP/Hct relationship is in part due to differences in endothelial function where menopause decreases the capacity of the endothelium to respond to increased blood viscosity and shears stress, leading to the increased production of vasodilator mediators to compensate for changes in blood viscosity due to changes in Hct. Comparison with a large group of postmenopause women in the city of Stockholm showed identical trends.Keywords: menopause, endothelial dysfunction, blood viscosity, blood pressure, hematocrit

  18. Brachial artery vasomotion and transducer pressure effect on measurements by active contour segmentation on ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Cary, Theodore W.; Sultan, Laith R.; Sehgal, Chandra M., E-mail: sehgalc@uphs.upenn.edu [Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Reamer, Courtney B.; Mohler, Emile R. [Department of Medicine, Division of Cardiovascular Medicine, Section of Vascular Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

    2014-02-15

    Purpose: To use feed-forward active contours (snakes) to track and measure brachial artery vasomotion on ultrasound images recorded in both transverse and longitudinal views; and to compare the algorithm's performance in each view. Methods: Longitudinal and transverse view ultrasound image sequences of 45 brachial arteries were segmented by feed-forward active contour (FFAC). The segmented regions were used to measure vasomotion artery diameter, cross-sectional area, and distention both as peak-to-peak diameter and as area. ECG waveforms were also simultaneously extracted frame-by-frame by thresholding a running finite-difference image between consecutive images. The arterial and ECG waveforms were compared as they traced each phase of the cardiac cycle. Results: FFAC successfully segmented arteries in longitudinal and transverse views in all 45 cases. The automated analysis took significantly less time than manual tracing, but produced superior, well-behaved arterial waveforms. Automated arterial measurements also had lower interobserver variability as measured by correlation, difference in mean values, and coefficient of variation. Although FFAC successfully segmented both the longitudinal and transverse images, transverse measurements were less variable. The cross-sectional area computed from the longitudinal images was 27% lower than the area measured from transverse images, possibly due to the compression of the artery along the image depth by transducer pressure. Conclusions: FFAC is a robust and sensitive vasomotion segmentation algorithm in both transverse and longitudinal views. Transverse imaging may offer advantages over longitudinal imaging: transverse measurements are more consistent, possibly because the method is less sensitive to variations in transducer pressure during imaging.

  19. The mechanical properties of the systemic and pulmonary arteries of Python regius correlate with blood pressures.

    Science.gov (United States)

    van Soldt, Benjamin J; Danielsen, Carl Christian; Wang, Tobias

    2015-12-01

    Pythons are unique amongst snakes in having different pressures in the aortas and pulmonary arteries because of intraventricular pressure separation. In this study, we investigate whether this correlates with different blood vessel strength in the ball python Python regius. We excised segments from the left, right, and dorsal aortas, and from the two pulmonary arteries. These were subjected to tensile testing. We show that the aortic vessel wall is significantly stronger than the pulmonary artery wall in P. regius. Gross morphological characteristics (vessel wall thickness and correlated absolute amount of collagen content) are likely the most influential factors. Collagen fiber thickness and orientation are likely to have an effect, though the effect of collagen fiber type and cross-links between fibers will need further study.

  20. Cardiovascular responses to lead are biphasic, while methylmercury, but not inorganic mercury, monotonically increases blood pressure in rats.

    Science.gov (United States)

    Wildemann, Tanja M; Mirhosseini, Naghmeh; Siciliano, Steven D; Weber, Lynn P

    2015-02-01

    Cardiovascular diseases, such as heart attack and stroke, are the major cause of death worldwide. It is well known that a high number of environmental and physiological risk factors contribute to the development of cardiovascular diseases. Although risk factors are additive, increased blood pressure (hypertension) is the greatest risk factor. Over the last two decades, a growing number of epidemiological studies associate environmental exposure to lead or mercury species with hypertension. However, cardiovascular effects beyond blood pressure are rarely studied and thresholds for effect are not yet clear. To explore effects of lead or mercury species on the cardiovascular system, normal male Wistar rats were exposed to a range of doses of lead, inorganic mercury or methylmercury through the drinking water for four weeks. High-resolution ultrasound was used to measure heart and vascular function (carotid artery blood flow) at baseline and at the end of the exposure, while blood pressure was measured directly in the femoral artery at the end of the 4-week exposure. After 4 weeks, blood pressure responses to lead were biphasic. Low lead levels decreased blood pressure, dilated the carotid artery and increased cardiac output. At higher lead doses, rats had increased blood pressure. In contrast, methylmercury-exposed rats had increased blood pressure at all doses despite dilated carotid arteries. Inorganic mercury did not show any significant cardiovascular effects. Based on the current study, the benchmark dose level 10% (BMDL10s) for systolic blood pressure for lead, inorganic mercury and methylmercury are 1.1, 1.3 and 1.0 μg/kg-bw/d, respectively. However, similar total mercury blood levels attributed to inorganic mercury or methylmercury produced strikingly different results with inorganic mercury having no observable effect on the cardiovascular system but methylmercury increasing systolic and pulse pressures. Therefore, adverse cardiovascular effects cannot be

  1. Fast and Accurate Pressure-Drop Prediction in Straightened Atherosclerotic Coronary Arteries

    NARCIS (Netherlands)

    J.T.C. Schrauwen (Jelle); D. Koeze (Dion); J.J. Wentzel (Jolanda); F.N. van de Vosse (Frans); A.F.W. van der Steen (Ton); F.J.H. Gijsen (Frank)

    2014-01-01

    textabstractAtherosclerotic disease progression in coronary arteries is influenced by wall shear stress. To compute patient-specific wall shear stress, computational fluid dynamics (CFD) is required. In this study we propose a method for computing the pressure-drop in regions proximal and distal to

  2. Geometry-based pressure drop prediction in mildly diseased human coronary arteries

    NARCIS (Netherlands)

    J.T.C. Schrauwen (Jelle); J.J. Wentzel (Jolanda); A.F.W. van der Steen (Ton); F.J.H. Gijsen (Frank)

    2014-01-01

    textabstractPressure drop (△. p) estimations in human coronary arteries have several important applications, including determination of appropriate boundary conditions for CFD and estimation of fractional flow reserve (FFR). In this study a △. p prediction was made based on geometrical features deri

  3. Pressure profile and morphology of the arteries along the giraffe limb

    DEFF Research Database (Denmark)

    Østergaard, Kristine Hovkjær; Bertelsen, Mads F.; Brøndum, Emil;

    2011-01-01

    Giraffes are the tallest animals on earth and the effects of gravity on their cardiovascular system have puzzled physiologists for centuries. The authors measured arterial and venous pressure in the foreleg of anesthetized giraffes, suspended in upright standing position, and determined the ratio...

  4. Proprioceptive Neuromuscular Facilitation Flexibility Techniques: Acute Effects on Arterial Blood Pressure.

    Science.gov (United States)

    Cornelius, William L.; Craft-Hamm, Kelley

    1988-01-01

    The effects of stretching techniques on arterial blood pressure (ABP) were studied in three groups of 20 men each. Each group performed one of three proprioceptive neuromuscular facilitation (PNF) techniques. Results are presented. The study indicates that the benefits of stretching may outweigh the risk of elevated ABP. (JL)

  5. External iliac artery injury secondary to indirect pressure wave effect from gunshot wound

    OpenAIRE

    Ng, Eugene; Choong, Andrew MTL

    2016-01-01

    In patients presenting with gunshot wounds, a high clinical suspicion of injury to vasculature and viscera remote from the projectile track is paramount. We present a case of a 17 year old male who sustained a gunshot wound to his abdomen and subsequently developed a right external iliac artery contusion requiring surgery as an indirect effect of the pressure wave from the bullet.

  6. Long-term pressure monitoring with arterial applanation tonometry : a non-invasive alternative during clinical intervention?

    NARCIS (Netherlands)

    Matthys, Koen S; Kalmar, Alain F; Struys, Michel M R F; Mortier, Eric P; Avolio, Alberto P; Segers, Patrick; Verdonck, Pascal R

    2008-01-01

    Arterial tonometry is a non-invasive technique for continuous registration of arterial pressure waveforms. This study aims to assess tonometric blood pressure recording (TBP) as an alternative for invasive long-term bedside monitoring. A prospective study was set up where patients undergoing neurosu

  7. Kidney transplant artery stenosis. Interrelationship between blood pressure, kidney function, renin-aldosterone system and body sodium content.

    Science.gov (United States)

    Kornerup, H J; Pedersen, E B; Fjeldborg, O

    1977-01-01

    Among 9 hypertensive recipients with kidney transplant artery stenosis (KTAS) evidence of increased activity of the renin system was present in 3. Surgical repair of KTAS in 4 recipients resulted in an increase in renal plasma flow and glomerular filtration rate associated with a decrease in exchangeable sodium and blood pressure. Peripheral plasma renin and aldosterone values were normal before and after operation in all. It is suggested that sodium retention may counterbalance increased activity of the renin system in KTAS. Preoperative determinations of plasma renin do not predict the effect of surgical repair of KTAS on hypertension.

  8. Differential increases in blood flow velocity in the middle cerebral artery after tourniquet deflation during sevoflurane, isoflurane or propofol anaesthesia.

    Science.gov (United States)

    Kadoi, Y; Kawauchi, C H; Ide, M; Saito, S; Mizutani, A

    2009-07-01

    The purpose of this study was to examine the comparative effects of sevoflurane, isoflurane or propofol on cerebral blood flow velocity after tourniquet deflation during orthopaedic surgery. Thirty patients undergoing elective orthopaedic surgery were randomly divided into sevoflurane, isoflurane and propofol groups. Anaesthesia was maintained with sevoflurane, isoflurane or propofol infusion in 33% oxygen and 67% nitrous oxide, in whatever concentrations were necessary to keep bispectral index values between 45 and 50. Ventilatory rate or tidal volume was adjusted to target PaCO2 of 35 mmHg. A 2.0 MHz transcranial Doppler probe was attached to the patient's head at the temporal window and mean blood flow velocity in the middle cerebral artery was continuously measured. The extremity was exsanguinated with an Esmarch bandage and the pneumatic tourniquet was inflated to a pressure of 450 mmHg. Arterial blood pressure, heart rate, velocity in the middle cerebral artery and arterial blood gas analysis were measured every minute for 10 minutes after release of the tourniquet in all three groups. Velocity in the middle cerebral artery in the three groups increased for five minutes after tourniquet deflation. Because of the different cerebrovascular effects of the three agents, the degree of increase in flow velocity in the isoflurane group was greater than in the other two groups, the change in flow velocity in the propofol group being the lowest (at three minutes after deflation 40 +/- 7%, 32 +/- 6% and 28 +/- 10% in the isoflurane, sevoflurane and propofol groups respectively, P < 0.05).

  9. Phylloquinone (vitamin K₁) intake and pulse pressure as a measure of arterial stiffness in older adults.

    Science.gov (United States)

    Vaccaro, Joan A; Huffman, Fatma G

    2013-01-01

    This study examined the relationships among ethnicity/race, lifestyle factors, phylloquinone (vitamin K₁) intake, and arterial pulse pressure in a nationally representative sample of older adults from four ethnic/racial groups: non-Hispanic Whites, non-Hispanic Blacks, Mexican Americans, and other Hispanics. This was a cross-sectional study of U.S. representative sample with data from the National Health and Nutrition Examination Surveys, 2007-2008 and 2009-2010 of adults aged 50 years and older (N = 5296). Vitamin K intake was determined by 24-hour recall. Pulse pressure was calculated as the difference between the averages of systolic blood pressure and diastolic blood pressure. Compared to White non-Hispanics, the other ethnic/racial groups were more likely to have inadequate vitamin K₁ intake. Inadequate vitamin K₁ intake was an independent predictor of high arterial pulse pressure. This was the first study that compared vitamin K₁ inadequacy with arterial pulse pressure across ethnicities/races in U.S. older adults. These findings suggest that vitamin K screening may be a beneficial marker for the health of older adults.

  10. A comparison of pulmonary arterial occlusion algorithms for estimation of pulmonary capillary pressure.

    Science.gov (United States)

    Pellett, A A; Johnson, R W; Morrison, G G; Champagne, M S; deBoisblanc, B P; Levitzky, M G

    1999-07-01

    Using the arterial occlusion method, we compared five literature-based estimates of pulmonary capillary pressure (Ppc) with the corresponding double occlusion pressures (Pdo) in anesthetized dogs whose chests had been closed after sternotomy for instrumentation. Arterial occlusions were performed with a balloon-tipped pulmonary artery catheter that housed pressure transducers immediately proximal and distal to the balloon. Separation of the proximal and distal pressure waveforms during balloon inflation allowed us to precisely define the moment of occlusion. We fit a monoexponential curve to pressure data beginning 200 ms after the onset of occlusion and a biexponential curve to data beginning at the instant of occlusion, with data obtained over a range of vascular states (control, serotonin infusion, histamine infusion). In addition, we investigated the use of sampling of the raw data to estimate capillary pressure. Three of the five literature-based estimates of Ppc yielded values similar to Pdo. The optimal (least average difference from Pdo) interpolation/extrapolation time points of the curve fits varied, depending on the type of curve fitting and the state of the pulmonary vasculature. We also determined that a close approximation of Pdo may be derived from the raw data, as an alternative to exponential curve fitting.

  11. Increased rhythmicity in hypertensive arterial smooth muscle is linked to transient receptor potential canonical channels

    DEFF Research Database (Denmark)

    Chen, Xiaoping; Yang, Dachun; Ma, Shuangtao

    2010-01-01

    Vasomotion describes oscillations of arterial vascular tone due to synchronized changes of intracellular calcium concentrations. Since increased calcium influx into vascular smooth muscle cells from spontaneously hypertensive rats (SHR) has been associated with variances of transient receptor...

  12. Sleep Bruxism Is Associated with a Rise in Arterial Blood Pressure

    Science.gov (United States)

    Nashed, Angela; Lanfranchi, Paola; Rompré, Pierre; Carra, Maria Clotilde; Mayer, Pierre; Colombo, Roberto; Huynh, Nelly; Lavigne, Gilles

    2012-01-01

    Study Objectives: Sleep bruxism (SB) is a movement disorder identified by grinding of teeth and rhythmic masticatory muscle activity (RMMA). RMMA is associated with body movements and cortical arousals. Increases in autonomic sympathetic activities that characterize sleep cortical arousal precede RMMA/SB. Based on these findings, this study examined whether RMMA/SB episodes are also associated with significant changes in arterial blood pressure (BP). Design: Participants underwent 3 nights of full polysomnography that included noninvasive beat-to-beat BP recording. Single RMMA/SB episodes and arousal episodes were analyzed in stage 2 sleep and categorized as: (i) RMMA/SB + arousal; (ii) RMMA/SB + body movement; (iii) RMMA/SB + arousal + body movement; or (iv) arousal alone. Sleep and RMMA/SB data were compared to a Non SB group. RMMA/SB clusters (RMMA/SB episodes ≤ 30 sec apart) were also analyzed. Setting: Sleep Laboratory at l'Hôpital du Sacré-Coeur de Montréal. Participants: Ten young, healthy participants with SB (mean age = 26 ± 1.8 years) and 9 without SB (mean age = 29 ± 1.2 years). Interventions: N/A Measurements and Results: BP increased with all RMMA/SB and arousal episodes (P ≤ 0.05). The average maximum BP surges (systolic/diastolic ± SE mm Hg) were: 25.6 ± 3.3/12.6 ± 2.0 for RMMA/SB + arousal; 30.1 ± 1.7/19.1 ± 1.9 for RMMA/SB + body movement; 26.0 ± 2.8/15.1 ± 2.0 for RMMA/SB + arousal + body movement; 19.4 ± 2.3/8.9 ± 1.2 for arousal alone; and for RMMA/SB clusters: Episode: 1: 26.2 ± 8.7/16.4 ± 5.7; Episode 2: 21.1 ± 7.9/12.6 ± 6.4. Conclusion: Rhythmic masticatory muscle activity/sleep bruxism (RMMA/SB) is associated with blood pressure fluctuations during sleep. Arousals and body movements often occur with RMMA/SB and can impact the magnitude of this BP surge. Citation: Nashed A; Lanfranchi P; Rompré P; Carra MC; Mayer P; Colombo R; Huynh N; Lavigne G. Sleep bruxism is associated with a rise in arterial blood pressure. SLEEP

  13. Activity of the positive and negative reinforcement motivation systems and baseline arterial blood pressure in humans.

    Science.gov (United States)

    Aftanas, L I; Sidorova, P V; Pavlov, S V; Makhnev, V P; Korenek, V V; Reva, N V; Amstislavskaya, T G

    2008-10-01

    The aim of the present work was to identify possible associations between individual balances in the activity of the positive and negative reinforcement motivation systems using a method based on emotional modulation of the startle reaction (EMSR) by motivationally significant emotionally positive and negative contextual visual stimuli and measures of cardiovascular system activity. Studies were performed using healthy males (mean age 30.29 +/- 9.8 years) with normal and first-episode excessive increases in arterial blood pressure (systolic blood pressure to greater than 140 mmHg, diastolic to greater than 90 mmHg). Cluster analysis of EMSR data identified groups of individuals with different activity profiles for the positive and negative reinforcement systems. Groups of subjects with changes in the balance of activity towards a lower level of positive reinforcement system activity (smaller startle reflexes to positive contextual stimuli) or a higher level of negative reinforcement system activity (larger startle reactions to threatening contextual stimuli) showed significantly greater baseline SBP and DBP. The possible mechanisms of the modulatory influences of the balance of system activities on autonomic vascular regulatory processes are discussed.

  14. Impaired brachial artery flow-mediated dilation and increased carotid intima-media thickness in rheumatoid arthritis patients

    Institute of Scientific and Technical Information of China (English)

    FAN Chun-yan; ZHANG Zhi-yi; MEI Yi-fang; WU Chang-jun; SHEN Bao-zhong

    2012-01-01

    Background Carotid artery intima-media thickness (CIMT) and brachial artery flow-mediated dilation percentage (FMD%) are common parameters used for detecting subclinical atherosclerosis.This study compared subclinical atherosclerosis of the carotid and brachial arteries in rheumatoid arthritis (RA) patients and healthy controls using high resolution ultrasonography.We also investigated their correlation with clinical factors and the association between FMD% and CIMT.Methods One hundred and two RA patients and 46 age-gender matched healthy controls were included in the study.FMD of the brachial artery and CIMT were measured ultrasonographically.Patients with diabetes mellitus,hypertension,renal failure,history of cardiovascular or cerebrovascular disease were excluded.Subjects who were receiving or used high dose steroids were also excluded.Results The CIMT was significantly higher in patients than that in the control group ((0.697±0.053) vs.(0.554±0.051) mm,P <0.001),whereas brachial artery FMD% was lower in patients than that in the controls ((5.454±2.653)% vs.(8.477±2.851)%,P <0.001).CIMT was related to age,disease duration,tender and swollen joint score,C-reactive protein,systolic blood pressure and high-density lipoprotein.However,FMD% was only association with systolic blood pressure.There was no significant correlation between CIMT and FMD%.Conclusions Compared with the healthy control subjects,RA patients without clinically evident cardiovascular disease had subclinical atherosclerosis in terms of impaired FMD% and increased CIMT.FMD% and CIMT may measure a different stage of subclinical atherosclerosis in RA patients.

  15. Exploring Arterial Smooth Muscle Kv7 Potassium Channel Function using Patch Clamp Electrophysiology and Pressure Myography

    Science.gov (United States)

    Brueggemann, Lioubov I.; Mani, Bharath K.; Haick, Jennifer; Byron, Kenneth L.

    2012-01-01

    Contraction or relaxation of smooth muscle cells within the walls of resistance arteries determines the artery diameter and thereby controls flow of blood through the vessel and contributes to systemic blood pressure. The contraction process is regulated primarily by cytosolic calcium concentration ([Ca2+]cyt), which is in turn controlled by a variety of ion transporters and channels. Ion channels are common intermediates in signal transduction pathways activated by vasoactive hormones to effect vasoconstriction or vasodilation. And ion channels are often targeted by therapeutic agents either intentionally (e.g. calcium channel blockers used to induce vasodilation and lower blood pressure) or unintentionally (e.g. to induce unwanted cardiovascular side effects). Kv7 (KCNQ) voltage-activated potassium channels have recently been implicated as important physiological and therapeutic targets for regulation of smooth muscle contraction. To elucidate the specific roles of Kv7 channels in both physiological signal transduction and in the actions of therapeutic agents, we need to study how their activity is modulated at the cellular level as well as evaluate their contribution in the context of the intact artery. The rat mesenteric arteries provide a useful model system. The arteries can be easily dissected, cleaned of connective tissue, and used to prepare isolated arterial myocytes for patch clamp electrophysiology, or cannulated and pressurized for measurements of vasoconstrictor/vasodilator responses under relatively physiological conditions. Here we describe the methods used for both types of measurements and provide some examples of how the experimental design can be integrated to provide a clearer understanding of the roles of these ion channels in the regulation of vascular tone. PMID:23007713

  16. New Cardiovascular Indices Based on a Nonlinear Spectral Analysis of Arterial Blood Pressure Waveforms

    CERN Document Server

    Laleg, Taous-Meriem; Papelier, Yves; Crépeau, Emmanuelle; Sorine, Michel

    2007-01-01

    A new method for analyzing arterial blood pressure is presented in this report. The technique is based on the scattering transform and consists in solving the spectral problem associated to a one-dimensional Schr\\"odinger operator with a potential depending linearly upon the pressure. This potential is then expressed with the discrete spectrum which includes negative eigenvalues and corresponds to the interacting components of an N-soliton. The approach is similar to a nonlinear Fourier transform where the solitons play the role of sine and cosine components. The method provides new cardiovascular indices that seem to contain relevant physiological information. We first show how to use this approach to decompose the arterial blood pressure pulse into elementary waves and to reconstruct it or to separate its systolic and diastolic phases. Then we analyse the parameters computed from this technique in two physiological conditions, the head-up 60 degrees tilt test and the isometric handgrip test, widely used for...

  17. The effect of septoplasty on pulmonary artery pressure and right ventricular function in nasal septum deviation.

    Science.gov (United States)

    Ozkececi, Gulay; Akci, Onder; Bucak, Abdulkadir; Ulu, Sahin; Yalım, Zafer; Aycicek, Abdullah; Onrat, Ersel; Avsar, Alaettin

    2016-11-01

    Nasal septum deviation (NSD) can cause obstruction of the upper airway, which may lead to increased pulmonary artery pressure (PAP) and right ventricle dysfunction. The aim of the present study was to evaluate the effect of septoplasty on right ventricular function and mean PAP of patients with marked NSD. 25 patients with marked NSD (mean age = 31.8 ± 12.3 years) and 27 healthy volunteers (mean age = 34.5 ± 10.8 years) were enrolled. Echocardiography was performed for all subjects and right ventricular function and mean PAP were evaluated before and 3 months after septoplasty. Tricuspid annular plane systolic excursion (TAPSE) and tricuspid annulus early diastolic myocardial velocity (E') were significantly lower in patients with NSD than control subjects, while right ventricle myocardial performance index (RVMPI) and mean PAP were significantly higher (respectively, p = 0.006, 0.037, 0.049, 0.046). When preoperative and postoperative findings were compared, the mean PAP decreased whereas TAPSE increased significantly (respectively, p = 0.007, 0.03). The results of the present study demonstrated that mean PAP increased and right ventricular function worsened in patients with NSD. However, mean PAP decreased and right ventricular function tended to recover after septoplasty.

  18. Pressão arterial entre trabalhadores de curtume Blood pressure among tannery workers

    Directory of Open Access Journals (Sweden)

    Ricardo Cordeiro

    1998-10-01

    death in Brazil since the 1970s. High blood pressure has been the major risk factor among the above mentioned diseases. A negative correlation between occupational qualification and blood pressure has been observed among workers. The above mentioned facts bring out the importance of the knowledge of high blood pressure distribution among the different occupational groups. The aim of the present study was to describe the distribution of blood pressure in stable and homogeneous population of unskilled, low wage larning industrial workers. The Prevalence of high blood pressure was established for this specific group. This prevalence was also related to some biological and socio-economical covariates as compared with that among other occupational groups in Brazil. METHOD: The subjects were 73 active employees at a tannery in Botucatu, state of S.Paulo, Brazil, in July 1993. These subjects underwent blood pressure measurements, anamnesis and clinical examination. The results were compared with those of similar studies carried out in elsewhere Brazil. Age confounding was controlled by different techniques. RESULT: The crude prevalence of high blood pressure detected in this group of workers was of 56.1%, with 15.8% of isolated systolic hypertension. Alcohol abuse and smoking were associated with high blood pressure and isolated systolic hypertension in the population studied. DISCUSSION: Prevalence of hypertension in the group studied is significantly higher than that observed in other groups of workers studied in Brazil. Such a finding points to the need for further investigation so as to isolate those factors involved in the increased blood pressure found in this group.

  19. Inhibition of natriuretic factors increases blood pressure in rats.

    Science.gov (United States)

    Banday, Anees Ahmad; Lokhandwala, Mustafa F

    2009-08-01

    Renal dopamine and nitric oxide contribute to natriuresis during high-salt intake which maintains sodium and blood pressure homeostasis. We wanted to determine whether concurrent inhibition of these natriuretic factors increases blood pressure during high-sodium intake. Male Sprague-Dawley rats were divided into the following groups: 1) vehicle (V)-tap water, 2) NaCl-1% NaCl drinking water, 3) 30 mM l-buthionine sulfoximine (BSO), an oxidant, 4) BSO plus NaCl, and 5) BSO plus NaCl with 1 mM tempol (antioxidant). Compared with V, NaCl intake for 10 days doubled sodium intake and increased urinary dopamine level but reduced urinary nitric oxide content. NaCl intake also reduced basal renal proximal tubular Na-K-ATPase activity with no effect on blood pressure. However, NaCl intake in BSO-treated rats failed to reduce basal Na-K-ATPase activity despite higher urinary dopamine levels. Also, dopamine failed to inhibit proximal tubular Na-K-ATPase activity and these rats exhibited reduced urinary nitric oxide levels and high blood pressure. Tempol supplementation in NaCl plus BSO-treated rats reduced blood pressure. BSO treatment alone did not affect the urinary nitric oxide and dopamine levels or blood pressure. However, dopamine failed to inhibit proximal tubular Na-K-ATPase activity in BSO-treated rats. BSO treatment also increased basal protein kinase C activity, D1 receptor serine phosphorylation, and oxidative markers like malondialdehyde and 8-isoprostane. We suggest that NaCl-mediated reduction in nitric oxide does not increase blood pressure due to activation of D1 receptor signaling. Conversely, oxidative stress-provoked inhibition of D1 receptor signaling fails to elevate blood pressure due to presence of normal nitric oxide. However, simultaneously decreasing nitric oxide levels with NaCl and inhibiting D1 receptor signaling with BSO elevated blood pressure.

  20. Arterial blood pressure and renal sodium excretion in dopamine D3 receptor knockout mice.

    Science.gov (United States)

    Staudacher, Torsten; Pech, Bärbel; Tappe, Michael; Gross, Gerhard; Mühlbauer, Bernd; Luippold, Gerd

    2007-01-01

    Alterations in the dopaminergic system may contribute to the development of hypertension. Recently, it has been reported that pentobarbital-anesthetized mice with deficient dopamine D(3) receptors showed renin-dependent elevation in blood pressure. In a series of experiments, we evaluated the contribution of the dopamine D(3) receptor to the renal sodium excretion and arterial blood pressure behavior in conscious as well as anesthetized dopamine D(3) receptor knockout (-/-) mice. The blood pressure measuring study was designed as a cross-over trial to investigate the influence of different sodium loads. The animals were fed a normal salt diet (0.6% NaCl, NS) for 1 week and afterwards a low (0.2% NaCl, LS) or a high salt diet (4.6% NaCl, HS) for 2 weeks. After the third week, the animals were switched to the corresponding protocol. Systolic blood pressure in conscious (-/-) mice measured by tail-cuff plethysmography was not different from that of wild-type (+/+) animals, irrespective of the time course or the salt diet. In another experiment, challenge of an acute sodium loading per gavage in conscious D(3) receptor (-/-) and (+/+) animals on HS or NS diet did not show significant differences in renal sodium excretion between the two genotypes. Additionally, animals were fed an NS diet for 1 week and an HS diet for another week. As expected, sodium excretion significantly increased after the change from the NS to the HS diet. A slightly lower urinary sodium excretion was observed when comparing D(3) receptor (-/-) mice to their corresponding (+/+) mice, both on an HS diet. Clearance experiments with anesthetized D(3) receptor (-/-) and (+/+) mice were performed to investigate the renal sodium excretion capacity, when exposed to a moderate volume expansion (VE). Urinary sodium excretion increased in response to the VE; however, no difference were observed between the two genotypes. Taking these results together, we conclude that in the present animal model renal

  1. Proximal pulmonary arterial obstruction decreases the time constant of the pulmonary circulation and increases right ventricular afterload.

    Science.gov (United States)

    Pagnamenta, Alberto; Vanderpool, Rebecca; Brimioulle, Serge; Naeije, Robert

    2013-06-01

    The time constant of the pulmonary circulation, or product of pulmonary vascular resistance (PVR) and compliance (Ca), called the RC-time, has been reported to remain constant over a wide range of pressures, etiologies of pulmonary hypertension, and treatments. We wondered if increased wave reflection on proximal pulmonary vascular obstruction, like in operable chronic thromboembolic pulmonary hypertension, might also decrease the RC-time and thereby increase pulse pressure and right ventricular afterload. Pulmonary hypertension of variable severity was induced either by proximal obstruction (pulmonary arterial ensnarement) or distal obstruction (microembolism) eight anesthetized dogs. Pulmonary arterial pressures (Ppa) were measured with high-fidelity micromanometer-tipped catheters, and pulmonary flow with transonic technology. Pulmonary ensnarement increased mean Ppa, PVR, and characteristic impedance, decreased Ca and the RC-time (from 0.46 ± 0.07 to 0.30 ± 0.03 s), and increased the oscillatory component of hydraulic load (Wosc/Wtot) from 25 ± 2 to 29 ± 2%. Pulmonary microembolism increased mean Ppa and PVR, with no significant change in Ca and characteristic impedance, increased RC-time from 0.53 ± 0.09 to 0.74 ± 0.05 s, and decreased Wosc/Wtot from 26 ± 2 to 13 ± 2%. Pulse pressure increased more after pulmonary ensnarement than after microembolism. Concomitant measurements with fluid-filled catheters showed the same functional differences between the two types of pulmonary hypertension, with, however, an underestimation of Wosc. We conclude that pulmonary hypertension caused by proximal vs. distal obstruction is associated with a decreased RC-time and increased pulsatile component of right ventricular hydraulic load.

  2. Increased arterial stiffness and extracellular matrix reorganization in intrauterine growth–restricted fetal sheep

    Science.gov (United States)

    Dodson, Reuben Blair; Rozance, Paul J.; Fleenor, Bradley S.; Petrash, Carson C.; Shoemaker, Lauren G.; Hunter, Kendall S.; Ferguson, Virginia L.

    2013-01-01

    BACKGROUND Fetal intrauterine growth restriction (IUGR) results in increased placental resistance to blood flow, fetal hypertension, and increased pulsatility stresses shown to lead to vascular remodeling. We tested our hypothesis that IUGR causes decreased compliance in the carotid and umbilical arteries due to altered extracellular matrix (ECM) composition and structure. METHODS A sheep model of placental insufficiency–induced IUGR (PI-IUGR) was created by exposure of the pregnant ewe to elevated ambient temperatures. Umbilical and carotid arteries from near-term fetuses were tested with pressure–diameter measurements to compare passive compliance in control and PI-IUGR tissues. ECM composition was measured via biochemical assay, and the organization was determined by using histology and second-harmonic generation imaging. RESULTS We found that PI-IUGR increased arterial stiffness with increased collagen engagement, or transition stretch. PI-IUGR carotid arteries exhibited increased collagen and elastin quantity, and PI-IUGR umbilical arteries exhibited increased sulfated glycosaminoglycans. Histomorphology showed altered collagen-to-elastin ratios with altered cellular proliferation. Increased stiffness indicates altered collagen-to-elastin ratios with less elastin contribution leading to increased collagen engagement. CONCLUSION Because vessel stiffness is a significant predictor in the development of hypertension, disrupted ECM deposition in IUGR provides a potential link between IUGR and adult hypertension. PMID:23154756

  3. Arterial blood oxygen saturation during blood pressure cuff-induced hypoperfusion

    Science.gov (United States)

    Kyriacou, P. A.; Shafqat, K.; Pal, S. K.

    2007-10-01

    Pulse oximetry has been one of the most significant technological advances in clinical monitoring in the last two decades. Pulse oximetry is a non-invasive photometric technique that provides information about the arterial blood oxygen saturation (SpO2) and heart rate, and has widespread clinical applications. When peripheral perfusion is poor, as in states of hypovolaemia, hypothermia and vasoconstriction, oxygenation readings become unreliable or cease. The problem arises because conventional pulse oximetry sensors must be attached to the most peripheral parts of the body, such as finger, ear or toe, where pulsatile flow is most easily compromised. Pulse oximeters estimate arterial oxygen saturation by shining light at two different wavelengths, red and infrared, through vascular tissue. In this method the ac pulsatile photoplethysmographic (PPG) signal associated with cardiac contraction is assumed to be attributable solely to the arterial blood component. The amplitudes of the red and infrared ac PPG signals are sensitive to changes in arterial oxygen saturation because of differences in the light absorption of oxygenated and deoxygenated haemoglobin at these two wavelengths. From the ratios of these amplitudes, and the corresponding dc photoplethysmographic components, arterial blood oxygen saturation (SpO2) is estimated. Hence, the technique of pulse oximetry relies on the presence of adequate peripheral arterial pulsations, which are detected as photoplethysmographic (PPG) signals. The aim of this study was to investigate the effect of pressure cuff-induced hypoperfusion on photoplethysmographic signals and arterial blood oxygen saturation using a custom made finger blood oxygen saturation PPG/SpO2 sensor and a commercial finger pulse oximeter. Blood oxygen saturation values from the custom oxygen saturation sensor and a commercial finger oxygen saturation sensor were recorded from 14 healthy volunteers at various induced brachial pressures. Both pulse

  4. Arterial blood oxygen saturation during blood pressure cuff-induced hypoperfusion

    Energy Technology Data Exchange (ETDEWEB)

    Kyriacou, P A [School of Engineering and Mathematical Sciences, City University, London EC1V 0HB (United Kingdom); Shafqat, K [School of Engineering and Mathematical Sciences, City University, London EC1V 0HB (United Kingdom); Pal, S K [St Andrew' s Centre for Plastic Surgery and Burns, Broomfield Hospital, Chelmsford, CM1 7ET (United Kingdom)

    2007-10-15

    Pulse oximetry has been one of the most significant technological advances in clinical monitoring in the last two decades. Pulse oximetry is a non-invasive photometric technique that provides information about the arterial blood oxygen saturation (SpO{sub 2}) and heart rate, and has widespread clinical applications. When peripheral perfusion is poor, as in states of hypovolaemia, hypothermia and vasoconstriction, oxygenation readings become unreliable or cease. The problem arises because conventional pulse oximetry sensors must be attached to the most peripheral parts of the body, such as finger, ear or toe, where pulsatile flow is most easily compromised. Pulse oximeters estimate arterial oxygen saturation by shining light at two different wavelengths, red and infrared, through vascular tissue. In this method the ac pulsatile photoplethysmographic (PPG) signal associated with cardiac contraction is assumed to be attributable solely to the arterial blood component. The amplitudes of the red and infrared ac PPG signals are sensitive to changes in arterial oxygen saturation because of differences in the light absorption of oxygenated and deoxygenated haemoglobin at these two wavelengths. From the ratios of these amplitudes, and the corresponding dc photoplethysmographic components, arterial blood oxygen saturation (SpO{sub 2}) is estimated. Hence, the technique of pulse oximetry relies on the presence of adequate peripheral arterial pulsations, which are detected as photoplethysmographic (PPG) signals. The aim of this study was to investigate the effect of pressure cuff-induced hypoperfusion on photoplethysmographic signals and arterial blood oxygen saturation using a custom made finger blood oxygen saturation PPG/SpO{sub 2} sensor and a commercial finger pulse oximeter. Blood oxygen saturation values from the custom oxygen saturation sensor and a commercial finger oxygen saturation sensor were recorded from 14 healthy volunteers at various induced brachial pressures

  5. Comparison of arterial pressure and plethysmographic waveform-based dynamic preload variables in assessing fluid responsiveness and dynamic arterial tone in patients undergoing major hepatic resection

    NARCIS (Netherlands)

    Vos, J. J.; Kalmar, A. F.; Struys, M. M. R. F.; Wietasch, J. K. G.; Hendriks, H. G. D.; Scheeren, T. W. L.

    2013-01-01

    Dynamic preload variables to predict fluid responsiveness are based either on the arterial pressure waveform (APW) or on the plethysmographic waveform (PW). We compared the ability of APW-based variations in stroke volume (SVV) and pulse pressure (PPV) and of PW-based plethysmographic variability in

  6. Impact of local endothelial challenge with cytomegalovirus or glycoprotein B on vasodilation in intact pressurized arteries from nonpregnant and pregnant mice.

    Science.gov (United States)

    Gombos, Randi B; Teefy, Jana; Lee, Albert; Hemmings, Denise G

    2012-10-01

    Cytomegalovirus (CMV) infections are associated with vascular diseases in the human population. We have previously shown vascular dysfunction in systemic and uterine arteries dissected from nonpregnant (NP) mouse CMV (mCMV)-infected mice that was further impaired during late pregnancy (LP). CMV attachment alone through glycoprotein B (GB) can generate signals that impact vascular tone regulation. However, the contribution of direct virus interactions with endothelium to the vascular dysfunction we previously observed after in vivo mCMV infection is not known. We used a pressure myograph system to infuse GB or whole intact mCMV inside arteries dissected from uninfected mice and assessed vasodilation to methacholine infused inside pressurized arteries rather than applied abluminally. These results were compared to those observed after methacholine infusion into untreated arteries dissected from mCMV-infected mice. In mesenteric arteries, vasodilation to infused methacholine did not differ among treatments in NP or LP groups in contrast to previously published studies. However, increased vasoconstrictor activity was unmasked after blocking thromboxane receptors or prostaglandin production. Vasodilation in uterine arteries from uninfected NP mice to infused methacholine was increased by both GB and whole intact mCMV pretreatment. Untreated uterine arteries from mCMV-infected NP mice showed even greater vasodilation. There was no effect of GB or whole intact mCMV pretreatment in uterine arteries from uninfected LP mice, whereas vasodilation to infused methacholine was reduced in untreated uterine arteries from mCMV-infected LP mice. CMV exerts direct effects on vascular function which should be considered during viral reactivation leading to viremia and during GB-based vaccine administration.

  7. Future Treatment of Hypertension: Shifting the Focus from Blood Pressure Lowering to Arterial Stiffness Modulation?

    Science.gov (United States)

    Fok, Henry; Cruickshank, J Kennedy

    2015-08-01

    Isolated systolic hypertension is the commonest form of hypertension from middle age onwards. Achieving target systolic blood pressure (BP) control remains difficult in everyday clinical practice and even under clinical trial conditions. Most antihypertensive medicines were designed to lower peripheral vascular resistance, which was considered the haemodynamic determinant of hypertension; most are effective in reducing steady but not pulsatile components of BP. Arterial stiffness, defined via aortic length-specific pulse wave velocity (PWV), is thought to be an important determinant of pulse pressure widening through its effects on the timing and amplitude of pressure wave reflection, and/or the aorta's Windkessel function, or its excess 'reservoir' pressure. Whereas pulse pressure is neither an independent nor consistent cardiovascular risk factor, particularly below the age of about 60 years, PWV has become the most powerful predictor of cardiovascular outcomes including mortality, independent of systolic, pulse, mean or other BP components. PWV is therefore a more direct target for treatment. This review addresses the potential therapeutic options for targeting arterial stiffness and the role of pulse pressure.

  8. COMPARISON OF HIGH-DEFINITION OSCILLOMETRIC AND DIRECT ARTERIAL BLOOD PRESSURE MEASUREMENT IN ANESTHETIZED CHEETAHS (ACINONYX JUBATUS).

    Science.gov (United States)

    Sant Cassia, Emma V; Boswood, Adrian; Tordiffe, Adrian S W

    2015-09-01

    Blood pressure measurement reveals important insights into the health of conscious and anesthetized individuals. This is of particular interest in cheetahs (Acinonyx jubatus), which in captivity are known to suffer from chronic diseases that may be associated with hypertension and which often require immobilization for transport or veterinary treatment. Invasive testing methods are considered the gold standard but are not practical in many settings. Consequently, it is important to evaluate the use of noninvasive methods in this species. Measurements for systolic, diastolic, and mean arterial pressure obtained using high-definition oscillometry (HDO) at the coccygeal artery were compared to simultaneous direct measurements obtained via catheterization of the femoral or dorsal pedal artery in eight anesthetized captive cheetahs during nine anesthetic events. Overall, HDO and direct measurements agreed most closely for mean arterial pressure, and the poorest agreement was observed for systolic pressure. There was a tendency for low diastolic pressures to be underestimated and for high diastolic pressures to be overestimated. Across all three parameters, HDO measurements from the tail overestimated directly measured pressures in the femoral artery and underestimated those in the dorsal pedal artery. HDO agreed most closely with directly measured dorsal pedal pressures. Mean arterial pressure showed the greatest precision (standard deviation of 10.2 mm Hg) and lowest bias (-1.2 mm Hg), with 75.9% of readings within 10 mm Hg of the direct dorsal pedal pressure. Agreement with systolic pressure was hindered by a high bias (-10.4 mm Hg), but if a correction factor of +10 mm Hg was applied to all systolic measurements, agreement was improved and 65.7% of readings were within 10 mm Hg of the direct pressure. When compared to criteria defined by the American College of Veterinary Internal Medicine for validation of blood pressure devices, results were favorable, but a

  9. Measuring the Pressure in the Superficial Inferior Epigastric Vein to Monitor for Venous Congestion in Deep Inferior Epigastric Artery Perforator Breast Reconstructions : A Pilot Study

    NARCIS (Netherlands)

    Smit, Jeroen M.; Audolfsson, Thorir; Whitaker, Iain S.; Werker, Paul M. N.; Acosta, Rafael; Liss, Anders G.

    2010-01-01

    During deep inferior epigastric artery perforator (DIEP) flap dissection, we noted that in many cases the superficial vein on the ipsilateral side of the flap was engorged and tense, and in others, it was empty. This led us to believe that the pressure is increased as the result of preferential outf

  10. Influence of a history of arterial hypertension and pretreatment blood pressure on the effect of angiotensin converting enzyme inhibition after acute myocardial infarction. Trandolapril Cardiac Evaluation Study

    DEFF Research Database (Denmark)

    Gustafsson, F; Køber, L; Torp-Pedersen, C

    1998-01-01

    inhibition after AMI complicated by left ventricular dysfunction may be of particular importance in patients with a history of arterial hypertension or a relatively high pretreatment blood pressure. However, further investigations are necessary to establish the clinical impact of these results.......OBJECTIVE: To evaluate the influence of a history of arterial hypertension and the level of pretreatment blood pressure on the efficacy of the angiotensin converting enzyme (ACE) inhibitor trandolapril on mortality and morbidity in patients with acute myocardial infarction (AMI) and left...... for a broad spectrum of potential confounders. Also, benefit from ACE inhibition increased with increasing blood pressure at the time of randomization. Significant interactions between benefit from ACE inhibition and hypertension history, and systolic and diastolic blood pressure were found. CONCLUSION: ACE...

  11. Accelerated reendothelialization, increased neovascularization and erythrocyte extravasation after arterial injury in BAMBI-/- mice.

    Directory of Open Access Journals (Sweden)

    Nicolas Guillot

    Full Text Available BACKGROUND: Intimal injury rapidly activates TGFβ and enhances vascular repair by the growth of endothelial (EC and vascular smooth muscle cells (VSMC. The response to the TGFβ family of growth factors can be modified by BAMBI (BMP, Activin, Membrane Bound Inhibitor acting as a non-signaling, competitive antagonist of TGFβ type I receptors such as ALK 1 and 5. In vivo the effect of BAMBI will depend on its cell-specific expression and of that of the ALK type receptors. We recently reported EC restricted BAMBI expression and genetic elimination of BAMBI resulting in an in vitro and in vivo phenotype characterized by endothelial activation and proliferation involving alternative pathway activation by TGFβ through ALK 1. METHODOLOGY/PRINCIPAL FINDINGS: To test the hypothesis that BAMBI modulates arterial response to injury via its effects on endothelial repair and arterial wall neovascularization we used a model of femoral arterial denudation injury in wild type (WT and BAMBI(-/- mice. Arterial response was evaluated at 2 and 4 weeks after luminal endothelial denudation of femoral arteries. The BAMBI(-/- genotype mice showed accelerated luminal endothelial repair at 2 weeks and a highly unusual increase in arterial wall neovascularization compared to WT mice. The exuberant intimal and medial neovessel formation with BAMBI(-/- genotype was also associated with significant red blood cell extravasation. The bleeding into the neointima at 2 weeks transiently increased it's area in the BAMBI(-/-genotype despite the faster luminal endothelial repair in this group. Vascular smooth muscle cells were decreased at 2 weeks in BAMBI(-/- mice, but comparable to wild type at 4 weeks. CONCLUSIONS/SIGNIFICANCE: The absence of BAMBI results in a highly unusual surge in arterial wall neovascularization that surprisingly mimiks features of intra-plaque hemorrhage of advanced atheroma in a mechanical injury model. This suggests important effects of BAMBI on

  12. Predicting electrocardiogram and arterial blood pressure waveforms with different Echo State Network architectures.

    Science.gov (United States)

    Fong, Allan; Mittu, Ranjeev; Ratwani, Raj; Reggia, James

    2014-01-01

    Alarm fatigue caused by false alarms and alerts is an extremely important issue for the medical staff in Intensive Care Units. The ability to predict electrocardiogram and arterial blood pressure waveforms can potentially help the staff and hospital systems better classify a patient's waveforms and subsequent alarms. This paper explores the use of Echo State Networks, a specific type of neural network for mining, understanding, and predicting electrocardiogram and arterial blood pressure waveforms. Several network architectures are designed and evaluated. The results show the utility of these echo state networks, particularly ones with larger integrated reservoirs, for predicting electrocardiogram waveforms and the adaptability of such models across individuals. The work presented here offers a unique approach for understanding and predicting a patient's waveforms in order to potentially improve alarm generation. We conclude with a brief discussion of future extensions of this research.

  13. Leave-one-out prediction error of systolic arterial pressure time series under paced breathing

    CERN Document Server

    Ancona, N; Marinazzo, D; Nitti, L; Pellicoro, M; Pinna, G D; Stramaglia, S

    2004-01-01

    In this paper we show that different physiological states and pathological conditions may be characterized in terms of predictability of time series signals from the underlying biological system. In particular we consider systolic arterial pressure time series from healthy subjects and Chronic Heart Failure patients, undergoing paced respiration. We model time series by the regularized least squares approach and quantify predictability by the leave-one-out error. We find that the entrainment mechanism connected to paced breath, that renders the arterial blood pressure signal more regular, thus more predictable, is less effective in patients, and this effect correlates with the seriousness of the heart failure. The leave-one-out error separates controls from patients and, when all orders of nonlinearity are taken into account, alive patients from patients for which cardiac death occurred.

  14. Effects of simulated microgravity on circadian rhythm of caudal arterial pressure and heart rate in rats and their underlying mechanism

    Directory of Open Access Journals (Sweden)

    Li CHEN

    2016-04-01

    Full Text Available Objective  To explore the effects of simulated microgravity on the circadian rhythm of rats' caudal arterial pressure and heart rate, and their underlying mechanism. Methods  Eighteen male SD rats (aged 8 weeks were randomly assigned to control (CON and tail suspension (SUS group (9 each. Rats with tail suspension for 28 days were adopted as the animal model to simulate microgravity. Caudal arterial pressure and heart rate of rats were measured every 3 hours. The circadian difference of abdominal aorta contraction was measured by aortic ring test. Western blotting was performed to determine and compare the protein expression level of clock genes such as Per2 (Period2, Bmal1 (Aryl hydrocarbon receptor nuclear translocatorlike and dbp (D element binding protein in suprachiasmatic nucleus (SCN and abdominal aorta of rats in CON and SUS group at different time points. Results  Compared with CON group, the caudal arterial pressure, both systolic and diastolic pressure, decreased significantly and the diurnal variability disappeared, meanwhile the heart rate increased obviously and also the diurnal variability disappeared in rats of SUS group. Compared with CON group, the contraction reactivity of abdominal aorta decreased with disappearence of the diurnal variability, and also the clock genes expression in SCN and abdominal aorta showed no diurnal variability in rats of SUS group. Conclusion  Simulated microgravity may lead to circadian rhythm disorders in rats' cardiovascular system, which may be associated with the changes of the clock genes expression. DOI: 10.11855/j.issn.0577-7402.2016.04.06

  15. Cardiac output in idiopathic normal pressure hydrocephalus: association with arterial blood pressure and intracranial pressure wave amplitudes and outcome of shunt surgery

    Directory of Open Access Journals (Sweden)

    Eide Per K

    2011-02-01

    Full Text Available Abstract Background In patients with idiopathic normal pressure hydrocephalus (iNPH responding to shunt surgery, we have consistently found elevated intracranial pressure (ICP wave amplitudes during diagnostic ICP monitoring prior to surgery. It remains unknown why ICP wave amplitudes are increased in these patients. Since iNPH is accompanied by a high incidence of vascular co-morbidity, a possible explanation is that there is reduced vascular compliance accompanied by elevated arterial blood pressure (ABP wave amplitudes and even altered cardiac output (CO. To investigate this possibility, the present study was undertaken to continuously monitor CO to determine if it is correlated to ABP and ICP wave amplitudes and the outcome of shunting in iNPH patients. It was specifically addressed whether the increased ICP wave amplitudes seen in iNPH shunt responders were accompanied by elevated CO and/or ABP wave amplitude levels. Methods Prospective iNPH patients (29 were clinically graded using an NPH grading scale. Continuous overnight minimally-invasive monitoring of CO and ABP was done simultaneously with ICP monitoring; the CO, ABP, and ICP parameters were parsed into 6-second time windows. Patients were assessed for shunt surgery on clinical grade, Evan's index, and ICP wave amplitude. Follow-up clinical grading was performed 12 months after surgery. Results ICP wave amplitudes but not CO or ABP wave amplitude, showed good correlation with the response to shunt treatment. The patients with high ICP wave amplitude did not have accompanying high levels of CO or ABP wave amplitude. Correlation analysis between CO and ICP wave amplitudes in individual patients showed different profiles [significantly positive in 10 (35% and significantly negative in 16 (55% of 29 recordings]. This depended on whether there was also a correlation between ABP and ICP wave amplitudes and on the average level of ICP wave amplitude. Conclusions These results gave no

  16. Time pressure increases cooperation in competitively framed social dilemmas.

    Directory of Open Access Journals (Sweden)

    Jeremy Cone

    Full Text Available What makes people willing to pay costs to benefit others? Does such cooperation require effortful self-control, or do automatic, intuitive processes favor cooperation? Time pressure has been shown to increase cooperative behavior in Public Goods Games, implying a predisposition towards cooperation. Consistent with the hypothesis that this predisposition results from the fact that cooperation is typically advantageous outside the lab, it has further been shown that the time pressure effect is undermined by prior experience playing lab games (where selfishness is the more advantageous strategy. Furthermore, a recent study found that time pressure increases cooperation even in a game framed as a competition, suggesting that the time pressure effect is not the result of social norm compliance. Here, we successfully replicate these findings, again observing a positive effect of time pressure on cooperation in a competitively framed game, but not when using the standard cooperative framing. These results suggest that participants' intuitions favor cooperation rather than norm compliance, and also that simply changing the framing of the Public Goods Game is enough to make it appear novel to participants and thus to restore the time pressure effect.

  17. Effect of Algerian Varieties Dates on Glycemic, Arterial Blood Pressure and Satiety Responses

    OpenAIRE

    Gourchala Freha, Mihoub Fatma, Derradj Meriem, Henchiri Cherifa

    2016-01-01

    The purpose of our study is to determine the Glycemic Indexes (GIs)of three Algerians varieties of dates in healthy subjects, evaluate the satiety and effect on arterial pressure after their consumption. We have first documented the chemical composition of the dates. 10 healthy subjects consumed the dates (carbohydrates content of 50 g) in order to determine the GIs. The responses of glycaemia were monitored during two hours after the dates taking and compared to the reference glucose. In a r...

  18. External iliac artery injury secondary to indirect pressure wave effect from gunshot wound

    Institute of Scientific and Technical Information of China (English)

    Eugene Ng; Andrew MTL.Choong

    2016-01-01

    In patients presenting with gunshot wounds,a high clinical suspicion of injury to vasculature and viscera remote from the projectile track is paramount.We present a case of a 17 year old male who sustained a gunshot wound to his abdomen and subsequently developed a right external iliac artery contusion requiring surgery as an indirect effect of the pressure wave from the bullet.

  19. Fourier Analysis of Peripheral Blood Pressure and Flow in Intraoperative Assessment of Infrainguinal Arterial Reconstructions

    Directory of Open Access Journals (Sweden)

    Cheshmedzhiev Mihail V.

    2014-08-01

    Full Text Available AIM: To assess infrainguinal arterial reconstructions by intraoperative flowmetry under the distal anastomosis using a fast Fourier transformation; calculate and compare the amplitude ratios of peripheral arterial blood pressure and volume flow before and after drug-induced vasodilation of occluded bypass grafts and bypass grafts that have been patent at least for 1 year. To find what magnitude of the change of these ratios indicate a long-term patency of the bypass grafting. PATIENTS AND METHODS: We compared the results of the intraoperative flowmetry tests of 97 patients with infrainguinal arterial reconstructions. The patients were divided into two groups based on the graft status: the grafts in 49 patients were patent for at least a year, and 48 patients had failed bypass. We used a fast Fourier transform (FFT of the pressure and blood flow waves and compared the ratios of their amplitudes before and after administration of a vasodilator drug into the graft. Comparing the ratios obtained before and those after administration of the drug we quantified their change in each group and analysed them. RESULTS: After a drug-induced vasodilation, the blood pressure and flow amplitude ratios for the group with compromised reconstructions were less than 1.9 times smaller than those before drug infusion, while for the group with bypass grafts that had been functional for at least 12 months the ratios declined by more than 1.9≈2 times. CONCLUSION: The magnitude of the change of amplitude ratios of the peripheral pressure and volume flow after drug-induced vasodilation can be used to make an assessment of the bypass graft and the distal arterial segment.

  20. Effects of terlipressin on systolic pulmonary artery pressure of patients with liver cirrhosis:An echocardiographic assessment

    Institute of Scientific and Technical Information of China (English)

    Engin Altintas; Necdet Akkus; Ramazan Gen; M. Rami Helvaci; Orhan Sezgin; Dilek Oguz

    2004-01-01

    AIM: Portopulmonary hypertension is a serious complication of chronic liver disease. Our aim was to search into the effect of terlipressin on systolic pulmonary artery pressure among cirrhotic patients.METHODS: Twelve patients (6 males and 6 females) with liver cirrhosis were recruited in the study. Arterial blood gas samples were obtained in sitting position at rest. Contrast enhanced echocardiography and measurements of systolic pulmonary artery pressure were performed before and after the intravenous injection of 2 mg terlipressin.RESULTS: Of 12 patients studied, the contrast enhanced echocardiography was positive in 5, and the positive findings in contrast enhanced echocardiography were reversed to normal in two after terlipressin injection. The mean systolic pulmonary artery pressure was 25.5±3.6 mmHg before terlipressin injection, and was 22.5±2.5 mmHg after terlipressin (P=0.003). The systolic pulmonary artery pressure was above 25 mmHg in seven of these 12 patients.After the terlipressin injection, systolic pulmonary artery pressure was <25 mmHg in four of these cases (58.3% vs 25%, P=0.04).CONCLUSION: Terlipressin can decrease the systolic pulmonary artery pressure in patients with liver cirrhosis.

  1. Dopamine-induced cyclic AMP increase in canine myocardium, kidney and superior mesenteric artery.

    Directory of Open Access Journals (Sweden)

    Kazuno,Hiroshi

    1982-04-01

    Full Text Available The effect of dopamine on cyclic AMP levels in tissue slices of canine myocardium and kidney, and in chopped superior mesenteric arterial wall was investigated to identify dopamine receptors. Tissues were incubated in modified Krebs-Henseleit Ringer bicarbonate solution at 37 degrees C for 20 min with test drugs, after 20-min preincubation. In the presence of 3-isobutyl-1-methylxanthine (IBMX, dopamine and apomorphine caused dose-dependent increases in cyclic AMP levels in the myocardium, kidney and superior mesenteric artery. Phentolamine significantly intensified the cyclic AMP-increasing effect of dopamine in the superior mesenteric artery, but it did not influence the cyclic AMP increase caused by dopamine or apomorphine in the myocardium and kidney. Propranolol markedly blocked the effect of dopamine on cyclic AMP levels in all tissues studied. Haloperidol slightly inhibited the effect of dopamine and completely blocked the effect of apomorphine in the myocardium and kidney. These data suggest that dopamine increases cyclic AMP levels by activating predominantly beta-adrenergic receptors and partly dopamine receptors in the canine myocardium, kidney and superior mesenteric artery. The present results also suggest that dopamine acts not only on beta-adrenergic and dopamine receptors but also on alpha-adrenergic receptors in the superior mesenteric artery. Contrary to the activation of beta-adrenergic and dopamine receptors, the activation of alpha-adrenergic receptors resulted in a decrease in cyclic AMP levels in this tissue.

  2. Application of intraoperative arterial pressure-based cardiac output monitoring for patients undergoing coronary artery bypass grafting surgery

    Institute of Scientific and Technical Information of China (English)

    LU Jia-kai; ZHU Chen; JING He; WANG Yi-jun; QING En-ming

    2012-01-01

    Background For patients undergoing off-pump coronary artery bypass grafting (OPCABG),it is important to establish a hemodynamic monitoring system to obtain powerful parameters for better intraoperative treatment.This study aimed to observe the clinical feasibility of artedal pressure-based cardiac output (APCO) for cardiac output (CO) monitoring and to evaluate the correlation between APCO and pulmonary artery catheter (PAC) for CO measurement for patients undergoing OPCABG intraoperatively.Methods Fifty patients of Amedcan Society of Anaesthesiologists (ASA) classification Ⅱ-Ⅲ,undergoing elective OPCABG at Beijing Anzhen Hospital were randomly enrolled into this study.All patients were assigned to CO monitoring by PAC and APCO simultaneously.Patients with pacemaker,severe valvular heart disease,left ventdcular ejection fraction (EF) <40%,cardiac arrhythmias,peripheral vascular disease,application of intra-aortic balloon pump (IABP) and emergent diversion to cardiac pulmonary bypass were excluded.The radial artery wavaform was analyzed to estimate the stroke volume (SV) and heart rate (HR) continuously.CO was calculated as SV x HR; other derived parameters were cardiac index (CI),stroke volume index (SVI),systemic vascular resistance (SVR),and systemic vascular resistance index (SVRI).PAC was placed via right internal jugular vein and the correct position was confirmed by PAC waveforms.Continuous cardiac output (CCO),CI and other hemodynamic parameters were monitored at following 5 time points:immediate after anesthesia induction (baseline value),anastomosis of left intemal mammary artery to left anterior descending artery (LAD),anastomosis of left circumflex (LCX),anastomosis of posterior descending artery (PDA) and immediate after sternal closure.Results In the 50 patients,preoperative echocardiography measured left ventricular EF was (52.8±11.5)%,and 35 patients (70%) showed regional wall motion abnormalities.The correlation coefficient of CO

  3. Severe hypovitaminosis D in chronic kidney disease: association with blood pressure and coronary artery calcification.

    Science.gov (United States)

    Pillar, Roberta; G Lopes, Miriam Ghedini; Rocha, Lillian Andrade; Cuppari, Lilian; Carvalho, Aluízio B; Draibe, Sérgio A; Canziani, Maria Eugênia F

    2013-05-01

    Hypovitaminosis D occurs early in the course of chronic kidney disease (CKD), and its association with cardiovascular morbidity and mortality is well known. In this study, we aimed to evaluate whether the degree of hypovitaminosis D may differently affect blood pressure (BP) and coronary artery calcification (CAC) in nondialyzed CKD patients. This study included 80 CKD patients with a creatinine clearance between 15 and 60 ml/min/1.73 m(2) and serum 25 hydroxivitamin D [25(OH)D] level hypovitaminosis D, were defined according to the median 25(OH)D value. Patients with severe hypovitaminosis D [25(OH)D hypovitaminosis D [25(OH)D >17.2 ng/ml; M-group]. No differences were found between the S and M-group in terms of diastolic BP and the presence of coronary calcification. In the multiple linear regression analysis, severe hypovitaminosis D was a predictor of 24-h, daytime and nighttime BP after controlling for a number of confounders. The severity of hypovitaminosis D was associated with increased BP in nondialyzed CKD patients. The degree of hypovitaminosis D was not related to CAC, which was equally elevated in both the severe and mild hypovitaminosis D groups.

  4. Healing of ulcers on the feet correlated with distal blood pressure measurements in occlusive arterial disease

    DEFF Research Database (Denmark)

    Holstein, P; Lassen, N A

    1980-01-01

    The frequency of healing in subchronic ulcers in 66 feet in 62 patients with arterial occlusive disease was correlated with the systolic digital blood pressure (SDBP) and the systolic ankle blood pressure (SABP), both measured with a strain gauge, and with the skin perfusion pressure on the heel...... of healing correlated significantly with the three distal blood pressure parameters investigated, the closest correlation being with the SDBP measured at the final examination, i.e. just after healing of the ulcer or just before an inevitable major amputation. Of the 22 cases with SDBP below 20 mmHg only two...... (SPPH) as measured with a photocell. Thirty-two patients (35 feet with ulcerations) had diabetes mellitus. The treatment was conservative. In 42 feet the ulcers healed after an average period of 5.8 months; in 24 feet major amputation became necessary after an average of 4.3 months. The frequency...

  5. Echocardiographic Assessment of Pulmonary Artery Systolic Pressure and Outcomes in Ambulatory Heart Failure Patients

    Science.gov (United States)

    Kalogeropoulos, Andreas P.; Siwamogsatham, Sarawut; Hayek, Salim; Li, Song; Deka, Anjan; Marti, Catherine N.; Georgiopoulou, Vasiliki V.; Butler, Javed

    2014-01-01

    Background Pulmonary hypertension (PH) in patients with heart failure (HF) is associated with worse outcomes and is rapidly being recognized as a therapeutic target. To facilitate pragmatic research efforts, data regarding the prognostic importance of noninvasively assessed pulmonary artery systolic pressure (PASP) in stable ambulatory patients with HF are needed. Methods and Results We examined the association between echocardiographic PASP and outcomes in 417 outpatients with HF (age, 54±13 years; 60.7% men; 50.4% whites; 24.9% with preserved ejection fraction). Median PASP was 36 mm Hg (interquartile range [IQR]: 29, 46). After a median follow‐up of 2.6 years (IQR: 1.7, 3.9) there were 72 major events (57 deaths; 9 urgent heart transplants; and 6 ventricular assist device implantations) and 431 hospitalizations for HF. In models adjusting for clinical risk factors and therapy, a 10‐mm Hg higher PASP was associated with 37% higher risk (95% CI: 18, 59; P<0.001) for major events, and 11% higher risk (95% CI: 1, 23; P=0.039) for major events or HF hospitalization. The threshold that maximized the likelihood ratio for both endpoints was 48 mm Hg; those with PASP ≥48 mm Hg (N=84; 20.1%) had an adjusted hazard ratio of 3.33 (95% CI: 1.96, 5.65; P<0.001) for major events and 1.47 (95% CI: 1.02, 2.11; P=0.037) for major events or HF hospitalization. Reduced right ventricular systolic function had independent prognostic utility over PASP for adverse outcomes. Right atrial pressure and transtricuspid gradient both contributed to risk. Conclusions Elevated PASP, determined by echocardiography, identifies ambulatory patients with HF at increased risk for adverse events. PMID:24492947

  6. The role of increased pulmonary blood flow in pulmonary arterial hypertension

    NARCIS (Netherlands)

    van Albada, ME; Schoemaker, RG; Kemna, MS; Cromme - Dijkhuis, A; van Veghel, R; Berger, RMF

    2005-01-01

    Chronic increased pulmonary blood flow is considered a pre-requisite for the induction of advanced vascular lesions in pulmonary arterial hypertension in congenital heart defects. The aim of the present study was to characterise the effects of increased pulmonary flow induced by an aortocaval shunt

  7. Coronary artery calcification is increased in patients with COPD and associated with increased morbidity and mortality

    DEFF Research Database (Denmark)

    Williams, M. C.; Murchison, J. T.; Edwards, L. D.;

    2014-01-01

    , functional capacity and outcomes in patients with COPD. Methods Coronary artery calcium score (CACS; Agatston score) was measured using chest CT in patients with COPD, smokers with normal spirometry and nonsmokers from the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE......) study. Results CACS was measured in 942 subjects: 672 with COPD (mean age+/-SD, 63+/-7 years; FEV1 49+/-16% predicted), 199 smokers with normal spirometry (54+/-9 years; FEV1 110+/-12% predicted) and 71 nonsmokers (55+/-9 years; FEV1 114+/-14% predicted). CACS was higher in patients with COPD than...

  8. Increased arterial distensibility and renovascular hypertension in Goldenhar syndrome Aumento de distensibilidade arterial e hipertensão renovascular na Sindrome de Goldenhar

    OpenAIRE

    Drager, Luciano F.; Hélio Bernardes Silva; Bortolotto, Luiz A

    2005-01-01

    This is a report of the successful angioplastic treatment of an association of renovascular hypertension with renal artery stenosis and the Goldenhar syndrome (a variant of oculoauriculovertebral dysplasia). For the first time to date, this association, which occurred in a 13-year-old girl, is reported. Additionally, increased arterial distensibility in spite of arterial hypertension was detected by noninvasive methods. The similarity of this finding and in those for other genetic diseases, s...

  9. Prenatal exposure to lipopolysaccharide results in increases in blood pressure and body weight in rats

    Institute of Scientific and Technical Information of China (English)

    Yan-ling WEI; Xiao-hui LI; Jian-zhi ZHOU

    2007-01-01

    Aim: To investigate the effects of prenatal exposure to lipopolysacchadde (LPS) on blood pressure and body weight of offspring in rats. Methods: Sixteen healthy,pregnant rats were randomly divided into 2 groups. The rats in the LPS group were injected intraperitoneally with LPS (0.79 mg/kg) on the d 8, d 10, and d 12 of gestation. Those in the control group were only treated with normal saline. After delivery, all offspring were weighed and blood pressure was measured by the tail-cuff method once every 2 weeks from the 6th to the 24th week. In the 15th week,their food intake was weighed every day. At the end of the 24th week, the rats were killed by decapitation. Abdominal adipose tissues were weighed, and the serum level of leptin was detected by radioimmunoassay. Results: The offspring with prenatal LPS exposure showed increased systemic arterial pressure, heavier body weight, elevated food intake, increased adipose tissue weight, and increased circulating leptin compared with the controls. Conclusion: Prenatal exposure to LPS leads to increases in blood pressure and body weight in rats.

  10. Maternal endotoxemia results in increases in blood pressure and body weight in rats

    Institute of Scientific and Technical Information of China (English)

    WEI Yan-ling; LI Xiao-hui

    2008-01-01

    Objective To investigate the effects of prenatal exposure to lipopolysaccharide (LPS) on blood pressure and body weight of offspring in rats. Methods Sixteen healthy pregnant rats were randomly divided into two groups. The rats in LPS group were injected intraperitoneally with LPS (0.79 mg·kg-1) at the 8th, 10th, 12th day of gestation. Those in the control group were only treated with NS. After delivery, all offspring were weighed and blood pressure was measured by tail-cuff method once every two weeks from the 6th to 24th week. In the 15th week, their food intakes were weighed every day. At the end of the 24th week, the rats were put to death by decapitation. Abdominal adipose tissues were taken to weigh, and serum level of leptin was detected by RIA. Results The offspring with prenatal LPS exposure showed increased systemic arterial pressure, heavier body weight, elevated food intake, increased adipose tissue weight and increased circulating leptin compared with controls. Conclusions Prenatal exposure to LPS leads to increases in blood pressure and body weight in rats.

  11. The relationship of pulmonary vascular resistance and compliance to pulmonary artery wedge pressure during submaximal exercise in healthy older adults

    Science.gov (United States)

    Wright, Stephen P.; Granton, John T.; Esfandiari, Sam; Goodman, Jack M.

    2016-01-01

    Key points A consistent inverse hyperbolic relationship has been observed between pulmonary vascular resistance and compliance, although changes in pulmonary artery wedge pressure (PAWP) may modify this relationship.This relationship predicts that pulmonary artery systolic, diastolic and mean pressure maintain a consistent relationship relative to the PAWP.We show that, in healthy exercising human adults, both pulmonary vascular resistance and compliance decrease in relation to exercise‐associated increases in PAWP.Pulmonary artery systolic, diastolic and mean pressures maintain a consistent relationship with one another, increasing linearly with increasing PAWP.Increases in PAWP in the setting of exercise are directly related to a decrease in pulmonary vascular compliance, despite small decreases in pulmonary vascular resistance, thereby increasing the pulsatile afterload to the right ventricle. Abstract The resistive and pulsatile components of right ventricular afterload (pulmonary vascular resistance, Rp; compliance, Cp) are related by an inverse hyperbolic function, expressed as their product known as RpCp‐time. The RpCp‐time exhibits a narrow range, although it may be altered by the pulmonary artery wedge pressure (PAWP). Identifying the determinants of RpCp‐time should improve our understanding of the physiological behaviour of pulmonary arterial systolic (PASP), diastolic (PADP) and mean (mPAP) pressures in response to perturbations. We examined the effect of exercise in 28 healthy non‐athletic adults (55 ± 6 years) who underwent right heart catheterization to assess haemodynamics and calculate Rp and Cp. Measurements were made at rest and during two consecutive 8–10 min stages of cycle ergometry, at targeted heart‐rates of 100 beats min–1 (Light) and 120 beats min–1 (Moderate). Cardiac output increased progressively during exercise. PASP, PADP, mPAP and PAWP increased for Light exercise, without any further rise for Moderate

  12. Oxidative stress mediated arterial dysfunction in patients with obstructive sleep apnoea and the effect of continuous positive airway pressure treatment

    Directory of Open Access Journals (Sweden)

    Del Ben Maria

    2012-07-01

    Full Text Available Abstract Background Several studies suggest an increase of oxidative stress and a reduction of endothelial function in obstructive sleep apnoea syndrome (OSAS. We assessed the association between OSAS, endothelial dysfunction and oxidative stress. Further aim was to evaluate the effect of nasal continuous positive airway pressure (nCPAP on oxidative stress and arterial dysfunction. Methods We studied 138 consecutive patients with heavy snoring and possible OSAS. Patients underwent unattended overnight home polysomnography. Ten patients with severe OSAS were revaluated after 6 months of nCPAP therapy. To assess oxidative stress in vivo, we measured urinary 8-iso-PGF2α and serum levels of soluble NOX2-derived peptide (sNOX2-dp. Serum levels of nitrite/nitrate (NOx were also determined. Flow-mediated brachial artery dilation (FMD was measured to asses endothelial function. Results Patients with severe OSAS had higher urinary 8-iso-PGF2α (p Conclusions The results of our study indicate that patients with OSAS and cardiometabolic comorbidities have increased oxidative stress and arterial dysfunction that are partially reversed by nCPAP treatment.

  13. Calculation and analysis of velocity and viscous drag in an artery with a periodic pressure gradient

    Science.gov (United States)

    Alizadeh, M.; Seyedpour, S. M.; Mozafari, V.; Babazadeh, Shayan S.

    2012-07-01

    Blood as a fluid that human and other living creatures are dependent on has been always considered by scientists and researchers. Any changes in blood pressure and its normal velocity can be a sign of a disease. Whatever significant in blood fluid's mechanics is Constitutive equations and finding some relations for analysis and description of drag, velocity and periodic blood pressure in vessels. In this paper, by considering available experimental quantities, for blood pressure and velocity in periodic time of a thigh artery of a living dog, at first it is written into Fourier series, then by solving Navier-Stokes equations, a relation for curve drawing of vessel blood pressure with rigid wall is obtained. Likewise in another part of this paper, vessel wall is taken in to consideration that vessel wall is elastic and its pressure and velocity are written into complex Fourier series. In this case, by solving Navier-Stokes equations, some relations for blood velocity, viscous drag on vessel wall and blood pressure are obtained. In this study by noting that vessel diameter is almost is large (3.7 mm), and blood is considered as a Newtonian fluid. Finally, available experimental quantities of pressure with obtained curve of solving Navier-Stokes equations are compared. In blood analysis in rigid vessel, existence of 48% variance in pressure curve systole peak caused vessel blood flow analysis with elastic wall, results in new relations for blood flow description. The Resultant curve is obtained from new relations holding 10% variance in systole peak.

  14. Inhibition of natriuretic factors increases blood pressure in rats

    OpenAIRE

    Banday, Anees Ahmad; Lokhandwala, Mustafa F.

    2009-01-01

    Renal dopamine and nitric oxide contribute to natriuresis during high-salt intake which maintains sodium and blood pressure homeostasis. We wanted to determine whether concurrent inhibition of these natriuretic factors increases blood pressure during high-sodium intake. Male Sprague-Dawley rats were divided into the following groups: 1) vehicle (V)-tap water, 2) NaCl-1% NaCl drinking water, 3) 30 mM l-buthionine sulfoximine (BSO), an oxidant, 4) BSO plus NaCl, and 5) BSO plus NaCl with 1 mM t...

  15. Nicorandil prevents right ventricular remodeling by inhibiting apoptosis and lowering pressure overload in rats with pulmonary arterial hypertension.

    Directory of Open Access Journals (Sweden)

    Xiang-Rong Zuo

    Full Text Available BACKGROUND: Most of the deaths among patients with severe pulmonary arterial hypertension (PAH are caused by progressive right ventricular (RV pathological remodeling, dysfunction, and failure. Nicorandil can inhibit the development of PAH by reducing pulmonary artery pressure and RV hypertrophy. However, whether nicorandil can inhibit apoptosis in RV cardiomyocytes and prevent RV remodeling has been unclear. METHODOLOGY/PRINCIPAL FINDINGS: RV remodeling was induced in rats by intraperitoneal injection of monocrotaline (MCT. RV systolic pressure (RVSP was measured at the end of each week after MCT injection. Blood samples were drawn for brain natriuretic peptide (BNP ELISA analysis. The hearts were excised for histopathological, ultrastructural, immunohistochemical, and Western blotting analyses. The MCT-injected rats exhibited greater mortality and less weight gain and showed significantly increased RVSP and RV hypertrophy during the second week. These worsened during the third week. MCT injection for three weeks caused pathological RV remodeling, characterized by hypertrophy, fibrosis, dysfunction, and RV mitochondrial impairment, as indicated by increased levels of apoptosis. Nicorandil improved survival, weight gain, and RV function, ameliorated RV pressure overload, and prevented maladaptive RV remodeling in PAH rats. Nicorandil also reduced the number of apoptotic cardiomyocytes, with a concomitant increase in Bcl-2/Bax ratio. 5-hydroxydecanoate (5-HD reversed these beneficial effects of nicorandil in MCT-injected rats. CONCLUSIONS/SIGNIFICANCE: Nicorandil inhibits PAH-induced RV remodeling in rats not only by reducing RV pressure overload but also by inhibiting apoptosis in cardiomyocytes through the activation of mitochondrial ATP-sensitive K(+ (mitoK(ATP channels. The use of a mitoK(ATP channel opener such as nicorandil for PAH-associated RV remodeling and dysfunction may represent a new therapeutic strategy for the amelioration of RV

  16. Arterial stiffness is not increased in patients with short duration rheumatoid arthritis and ankylosing spondylitis.

    Science.gov (United States)

    Dzieża-Grudnik, Anna; Sulicka, Joanna; Strach, Magdalena; Siga, Olga; Klimek, Ewa; Korkosz, Mariusz; Grodzicki, Tomasz

    2017-04-01

    Patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) have increased cardiovascular (CV) morbidity and mortality. Arterial stiffness is an independent predictor of CV events. The aim of the study was to assess arterial stiffness and inflammatory markers in patients with short duration chronic arthritis. We assessed carotid-femoral pulse wave velocity (PWV), augmentation index (AIx), traditional CV risk factors and inflammatory and endothelial markers in 71 chronic arthritis patients (RA and AS) and in 29 healthy controls. We did not find differences in PWV (for RA, AS and controls, respectively: 10 [8.8-10.9] versus 10.7 [9.1-11.8] versus 9.2 [8.3-11.4] m/s; p = .14) and AIx (for RA, AS and controls, respectively: 24.3 ± 11.5 versus 5.7 ± 12.4 versus 10 ± 12.8%; p = .22). Both groups of arthritis patients had active disease with significantly elevated inflammatory markers compared to controls. There were no correlations between endothelial and inflammatory markers and parameters of arterial stiffness in arthritis patients. When analyzing arthritis patients according to median of PVW, there were no significant differences in inflammatory and endothelial markers. We found that in patients with short duration active RA and AS arterial stiffness was not increased and furthermore, there was no association between markers of systemic inflammation and arterial stiffness.

  17. High selection pressure promotes increase in cumulative adaptive culture.

    Directory of Open Access Journals (Sweden)

    Carolin Vegvari

    Full Text Available The evolution of cumulative adaptive culture has received widespread interest in recent years, especially the factors promoting its occurrence. Current evolutionary models suggest that an increase in population size may lead to an increase in cultural complexity via a higher rate of cultural transmission and innovation. However, relatively little attention has been paid to the role of natural selection in the evolution of cultural complexity. Here we use an agent-based simulation model to demonstrate that high selection pressure in the form of resource pressure promotes the accumulation of adaptive culture in spite of small population sizes and high innovation costs. We argue that the interaction of demography and selection is important, and that neither can be considered in isolation. We predict that an increase in cultural complexity is most likely to occur under conditions of population pressure relative to resource availability. Our model may help to explain why culture change can occur without major environmental change. We suggest that understanding the interaction between shifting selective pressures and demography is essential for explaining the evolution of cultural complexity.

  18. Isobolographic analysis of the interaction between fenoldopam and levodopa on arterial blood pressure of the rat.

    Science.gov (United States)

    Quevedo, M; Prieto, J C; Miranda, H F; Pinardi, G

    2000-09-01

    Fenoldopam (FD) and levodopa (LD) injected intravenously in rats in a noncumulative schedule induced dose-dependent reductions in mean arterial blood pressure. The doses that induced a 50% reduction in the initial control mean arterial pressure (referred as ED50) were calculated by linear regression analysis of the corresponding parallel dose-response curves and were 0.88 and 0.068 mg/kg, respectively. The interaction between the effects of FD and LD on pressure reduction was evaluated by simultaneous administration of different fixed ratios of FD and LD (16:1) and obtaining a dose-response curve. An isobolographic analysis was then performed, which showed that the experimental point for the effect of the simultaneous administration of FD and LD was significantly different from the theoretically calculated additive point, denoting supradditivity. It was concluded that the effect of the combination of FD and LD on mean blood pressure reduction was synergic and was probably due to an activation of D1 vascular receptors by both drugs, in conjunction with an activation of beta2 adrenoceptors by LD and a blocking action of FD on postsynaptic alpha1-adrenoceptors.

  19. [Pulmonary artery wedge pressure and heart rate measurement during pharmacological stress induction for left cardial function diagnosis in horses with and without heart disease].

    Science.gov (United States)

    Gehlen, H; Groner, U; Rohn, K; Stadler, P

    2006-07-01

    In 18 horses, the pulmonary artery wedge pressure and the heart rate were measured during pharmacological stress load. 12 horses were healthy (4 trained, 8 untrained) and 6 horses had a heart disease (3 trained, 3 untrained). Pharmacological stress induction was carried out with the sympathomimetic drug dobutamine at a dosage rate of 7.5 microg/kg/min over 10 minutes of infusion. At the fourth minute, the parasympatholytic drug atropine was administered (5 microg/kg bw), and the heart rate and the pulmonary artery wedge pressure were continuously measured over 26 minutes. During sole dobutamine infusion, a significant decrease in heart rate and a significant increase in pulmonary artery wedge pressure were observed. After the application of atropine in the fourth minute, a significant increase in heart rate (from 35.7 +/- 6 up to 106 +/- 38/ min) and in pulmonary artery wedge pressure (from 15.7 +/- 3 up to 24 +/- 8.6 mmHg) were visible in the group of healthy horses. The horses with heart diseases had a significantly higher increase in both parameters (heart rate and pulmonary artery wedge pressure) with a significantly positive correlation (r = 0.7). The heart rate increased in the horses with heart diseases from 35.2 +/- 2,8 beats/min up to 132 +/- 45.7 beats/min and the pulmonary artery wedge pressure increased from 17.3 +/- 3,2 mmHg up to 32.7 +/- 13 mmHg. The cardiac status (healthy or heart disease) as well as the training level of the horses (untrained or trained) had a significant influence on the heart rate and the pulmonary artery wedge pressure. The untrained horses (healthy and heart disease) showed significantly higher values over a longer period of time than did the trained horses with the same cardiac status. Additionally the influence of pharmacological stress induction on echocardiographic parameters was investigated. The left atrial size (p = 0.015) and left ventricular diameter were significanly different in the systole (p = 0.008) and in the

  20. A RETROSPECTIVE STUDY OF THE IMPACT OF MEAN ARTERIAL PRESSURE ON ESTIMATED BLOOD LOSS DURING ENDOSCOPIC SINUS SURGERY

    Directory of Open Access Journals (Sweden)

    George W Williams

    2014-10-01

    Full Text Available The current practice of lowering mean arterial pressure (MAP during endoscopic sinus surgery (ESS is common, but unproven with regard to peer reviewed literature. The controlled hypotension induced is aimed for improved surgical field and lower the blood loss. Lower mean arterial pressures especially for prolonged surgeries may result in end organ hypoperfusion. The authors reviewed all patients who underwent outpatient endoscopic sinus surgery for the diagnosis of chronic sinusitis from January 1, 2012 to December 31, 2012 at Memorial Hermann Hospital – Texas Medical Centre. We individually reviewed case sheets of every patient and documented blood loss as recorded on the anaesthesia record or in the surgical procedure note, among other variables. A total of 326 patients were included in this study. The median estimated blood loss (EBL was found to be 50 ml. The multivariate regression analysis between these three groups showed that EBL was higher in MAP 75 group. The average of EBL in MAP75 group and the average of EBL in MAP 65-70 group is 42% higher than that in MAP>75 group when other variables were fixed. Hence we found the trend toward higher blood loss with lower MAP. The authors conclude that lower MAP does not result in lower EBL in endoscopic sinus surgery. Furthermore, increases in BMI and crystalloid administered during an aesthetic management of these cases correlates with increased estimate blood loss.

  1. The effects of venous cannulation technique and cardioplegia type on plasma potassium concentration and arterial blood pressure during cardiopulmonary bypass.

    LENUS (Irish Health Repository)

    Coleman, E T

    2012-02-03

    The cannulation method and cardioplegia solution used during cardiopulmonary bypass (CPB) may both influence plasma potassium concentrations ([K+]) and mean arterial blood pressure (MAP). Bi-caval or right atrial cannulation methods are routinely used in conjunction with crystalloid or blood cardioplegia. We investigated the influence of cannulation method and cardioplegia solutions on plasma [K+] and MAP during cardiopulmonary bypass. Sixty consecutive patients undergoing elective coronary artery bypass grafting (CABG) using CPB were studied. They were randomly divided into three groups of 20 patients. Patients in Group A underwent bi-caval venous cannulation and received crystalloid cardioplegia. Group B patients underwent right atrial cannulation and received crystalloid cardioplegia. Group C patients underwent right atrial cannulation and received blood cardioplegia. In each case. cardioplegia was administered antegrade via the aortic root. Plasma [K+], MAP. and hemoglobin concentration (Hb) were measured over an 8-min period following cardioplegia administration (pilot studies indicated pressure changes occuring post cardioplegia administration up to this time). The combination of bi-caval cannulation and crystalloid cardioplegia (Group A) was associated with the least increase in plasma [K+] and no decrease in MAP. The maximum [K+] for this Group was 4.2 mmol\\/L (4.6% increase). The minimum mean pressure was 57 mmHg (13.6% increase). Both right atrial cannulation groups (B and C) showed a large rise in plasma [K+] and a decrease in MAP. Group B maximum [K+] was 5.2 mmol\\/L (27.5% increase). Group C was also 5.2 mmol\\/L (26.0% increase). Group C showed the largest pressure decrease, the minimum mean pressure was 45 mmHg (21.3% decrease). The Group B minimum mean pressure was 45 mmHg (8.7% decrease). Our results show that patients undergoing CPB operations who are deemed to be at increased risk of suffering adverse effects from hypotensive episodes may

  2. Treinamento resistido controla a pressão arterial de ratos hipertensos induzidos por l-NAME Resistance training controls arterial blood pressure in rats with L-NAME- induced hypertension

    Directory of Open Access Journals (Sweden)

    Ayslan Jorge Santos de Araujo

    2013-04-01

    -NAME (40 mg/Kg to the drinking water for four weeks. Arterial pressure was evaluated before and after RT. RT was performed using 50% of 1RM, 3 sets of 10 repetitions, 3 times per week for four weeks. Vascular reactivity was measured in rat mesenteric artery rings by concentration-response curves to sodium nitroprusside (SNP; phenylephrine (PHE was also used for histological and stereological analysis. RESULTS: Resistance training inhibited the increase in mean and diastolic arterial pressures. Significant reduction was observed in Rmax (maximal response and pD2 (potency of PHE between SH and TH groups. Arteries demonstrated normal intima, media and adventitia layers in all groups. Stereological analysis demonstrated no significant difference in luminal, tunica media, and total areas of arteries in the SH and TH groups when compared to the SN group. Wall-to-lumen ratio of SH arteries was significantly different compared to SN arteries (p<0.05 but there was no difference when compared to TH arteries. CONCLUSIONS: RT was able to prevent an increase in blood pressure under the conditions in this study. This appears to involve a vasoconstrictor regulation mechanism and maintenance of luminal diameter in L-NAME induced hypertensive rats.

  3. Renal blood flow regulation and arterial pressure fluctuations: a case study in nonlinear dynamics

    DEFF Research Database (Denmark)

    Holstein-Rathlou, N H; Marsh, D J

    1994-01-01

    The arterial blood pressure, a physiological variable on which all renal excretory processes depend, fluctuates over a wide range of amplitudes and frequencies. Much of this variation originates in nonrenal vascular beds to support nonrenal tasks, and the fluctuations provide a noisy environment...... a relatively noise-free environment in which to work. Because of the time-varying nature of the blood pressure, we have concentrated in this review on the now substantial body of work on the dynamics of renal blood flow regulation and the underlying mechanisms. Renal vascular control mechanisms are not simply...... of experimental hypertension provide tubular pressure records that pass statistical tests for ordered structure and sensitive dependence on initial conditions in the reconstructed state space, two of the hallmarks of deterministic chaos. These records also pass recent more stringent tests for chaos...

  4. Arterial pressure and deltoid muscle gas tensions during cardiopulmonary bypass in man.

    Science.gov (United States)

    Stanley, T H

    1978-07-01

    The results of this study demonstrate that standard techniques of conducting cardiopulmonary bypass produce low muscle oxygen and high muscle carbon dioxide tensions and, thus, little perfusion of skeletal muscle. Our findings also show that PmO2 and PmCO2 do not return to pre-bypass levels until the mean arterial blood pressure exceeds 12 kPa (90 torr) during bypass and that utilization of vasopressor drugs during bypass maintains the pressure; but at the expense of muscle blood flow. The data indicate that both high mean blood pressure and high flow are necessary during bypass to ensure skeletal muscle perfusion and suggest, when combined with preliminary animal findings, that this type of bypass perfusion may prove to be superior to standard techniques in hastening recovery after cardio-pulmonary bypass.

  5. Chronic fluoxetine treatment increases NO bioavailability and calcium-sensitive potassium channels activation in rat mesenteric resistance arteries.

    Science.gov (United States)

    Pereira, Camila A; Ferreira, Nathanne S; Mestriner, Fabiola L; Antunes-Rodrigues, José; Evora, Paulo R B; Resstel, Leonardo B M; Carneiro, Fernando S; Tostes, Rita C

    2015-10-15

    Fluoxetine, a selective serotonin reuptake inhibitor (SSRI), has effects beyond its antidepressant properties, altering, e.g., mechanisms involved in blood pressure and vasomotor tone control. Although many studies have addressed the acute impact of fluoxetine on the cardiovascular system, there is a paucity of information on the chronic vascular effects of this SSRI. We tested the hypothesis that chronic fluoxetine treatment enhances the vascular reactivity to vasodilator stimuli by increasing nitric oxide (NO) signaling and activation of potassium (K+) channels. Wistar rats were divided into two groups: (I) vehicle (water for 21 days) or (II) chronic fluoxetine (10 mg/kg/day in the drinking water for 21 days). Fluoxetine treatment increased endothelium-dependent and independent vasorelaxation (analyzed by mesenteric resistance arteries reactivity) as well as constitutive NO synthase (NOS) activity, phosphorylation of eNOS at Serine1177 and NO production, determined by western blot and fluorescence. On the other hand, fluoxetine treatment did not alter vascular expression of neuronal and inducible NOS or guanylyl cyclase (GC). Arteries from fluoxetine-treated rats exhibited increased relaxation to pinacidil. Increased acetylcholine vasorelaxation was abolished by a calcium-activated K+ channel (KCa) blocker, but not by an inhibitor of KATP channels. On the other hand, vascular responses to Bay 41-2272 and 8-bromo-cGMP were similar between the groups. In conclusion, chronic fluoxetine treatment increases endothelium-dependent and independent relaxation of mesenteric resistance arteries by mechanisms that involve increased eNOS activity, NO generation, and KCa channels activation. These effects may contribute to the cardiovascular effects associated with chronic fluoxetine treatment.

  6. Visual Impairment/Increased Intracranial Pressure (VIIP): Layman's Summary

    Science.gov (United States)

    Fogarty, Jennifer

    2011-01-01

    To date NASA has documented that seven long duration astronauts have experienced in-flight and post-flight changes in vision and eye anatomy including degraded distant vision, swelling of the back of the eye, and changes in the shape of the globe. We have also documented in a few of these astronauts post-flight, increases in the pressure of the fluid that surrounds the brain and spinal cord. This is referred to as increased intracranial pressure (ICP). The functional and anatomical changes have varied in severity and duration. In the post-flight time period, some individuals have experienced a return to a pre-flight level of visual function while others have experienced changes that remain significantly altered compared to pre-flight. In addition, the increased ICP also persists in the post-flight time period. Currently, the underlying cause or causes of these changes is/are unknown but the spaceflight community at NASA suspects that the shift of blood toward the head and the changes in physiology that accompany it, such as increased intracranial pressure, play a significant role.

  7. An innovative method to measure the peripheral arterial elasticity: spring constant modeling based on the arterial pressure wave with radial vibration.

    Science.gov (United States)

    Wei, Ching-Chuan

    2011-11-01

    In this study, we propose an innovative method for the direct measurement of the peripheral artery elasticity using a spring constant model, based on the arterial pressure wave equation, vibrating in a radial direction. By means of the boundary condition of the pressure wave equation at the maximum peak, we can derive the spring constant used for evaluating peripheral arterial elasticity. The calculated spring constants of six typical subjects show a coincidence with their proper arterial elasticities. Furthermore, the comparison between the spring constant method and pulse wave velocity (PWV) was investigated in 70 subjects (21-64 years, 47 normotensives and 23 hypertensives). The results reveal a significant negative correlation for the spring constant vs. PWV (correlation coefficient = -0.663, p constant method to assess the arterial elasticity is carefully verified, and it is shown to be effective as well as fast. This method should be useful for healthcare, not only in improving clinical diagnosis of arterial stiffness but also in screening subjects for early evidence of cardio-vascular diseases and in monitoring responses to therapy in the future.

  8. Closure of digital arteries in high vascular tone states as demonstrated by measurement of systolic blood pressure in the fingers

    DEFF Research Database (Denmark)

    Krähenbühl, B; Nielsen, S L; Lassen, N A

    1977-01-01

    Finger systolic blood pressure (FSP) was measured indirectly in normal subjects and patients with primary Raynaud phenomenon by applying a thin-walled plastic cuff around the finger and a strain gauge more distally to detect volume changes. Inducing a high vascular tone in one or more fingers...... by direct cooling or intra-arterial noradrenaline infusion caused a marked drop in FSP in the exposed fingers, but not in the non-exposed fingers of the same hand. The fact that the non-exposed fingers retained the normal (arm systolic) pressure level is taken to indicate that palmar arch blood pressure...... also remained normal. In the high vascular tone state, a large transmural pressure difference must apparently be established before the digital arteries are forced open. The lowered opening pressure constitutes a manifestation of the closure phenomenon of the digital arteries described in patients...

  9. Monounsaturated fatty acid, carbohydrate intake, and diabetes status are associated with arterial pulse pressure

    Directory of Open Access Journals (Sweden)

    Vaccaro Joan A

    2011-11-01

    Full Text Available Abstract Background Diabetes is a global epidemic. Cardiovascular disease (CVD is one of the most prevalent consequences of diabetes. Nutrition is considered a modifiable risk factor for CVD, particularly for individuals with diabetes; albeit, there is little consensus on the role of carbohydrates, proteins and fats for arterial health for persons with or without diabetes. In this study, we examined the association of macronutrients with arterial pulse pressure (APP, a surrogate measure of arterial health by diabetes status and race. Methods Participants were 892 Mexican Americans (MA, 1059 Black, non-Hispanics (BNH and 2473 White, non-Hispanics (WNH with and without diabetes of a weighted sample from the National Nutrition and Health Examination Survey (NHANES 2007-2008. The cross-sectional analysis was performed with IBM-SPSS version 18 with the complex sample analysis module. The two-year sample weight for the sub-sample with laboratory values was applied to reduce bias and approximate a nationally, representative sample. Arterial stiffness was assessed by arterial pulse pressure (APP. Results APP was higher for MA [B = 0.063 (95% CI 0.015 to 0.111, p = 0.013] and BNH [B = 0.044 (95% CI 0.006 to 0.082, p = 0.018] than WNH, controlling for diabetes, age, gender, body mass index (BMI, fiber intake, energy intake (Kcal and smoking. A two-way interaction of diabetes by carbohydrate intake (grams was inversely associated with APP [B = -1.18 (95% CI -0.178 to -0.058, p = 0.001], controlling for race, age, gender, BMI, Kcal and smoking. BNH with diabetes who consumed more mono-unsaturated fatty acids (MUFA than WNH with diabetes had lower APP [B = -0.112 (95%CI-0.179 to -0.045, p = 0.003] adjusting for saturated fatty acids, Kcal, age, gender, BMI and smoking. Conclusion Higher MUFA and carbohydrate intake for persons with diabetes reflecting lower APP may be due to replacement of saturated fats with CHO and MUFA. The associations of APP with

  10. Evaluation of a new arterial pressure-based cardiac output device requiring no external calibration

    Directory of Open Access Journals (Sweden)

    Amann Matthias

    2007-11-01

    Full Text Available Abstract Background Several techniques have been discussed as alternatives to the intermittent bolus thermodilution cardiac output (COPAC measurement by the pulmonary artery catheter (PAC. However, these techniques usually require a central venous line, an additional catheter, or a special calibration procedure. A new arterial pressure-based cardiac output (COAP device (FloTrac™, Vigileo™; Edwards Lifesciences, Irvine, CA, USA only requires access to the radial or femoral artery using a standard arterial catheter and does not need an external calibration. We validated this technique in critically ill patients in the intensive care unit (ICU using COPAC as the method of reference. Methods We studied 20 critically ill patients, aged 16 to 74 years (mean, 55.5 ± 18.8 years, who required both arterial and pulmonary artery pressure monitoring. COPAC measurements were performed at least every 4 hours and calculated as the average of 3 measurements, while COAP values were taken immediately at the end of bolus determinations. Accuracy of measurements was assessed by calculating the bias and limits of agreement using the method described by Bland and Altman. Results A total of 164 coupled measurements were obtained. Absolute values of COPAC ranged from 2.80 to 10.80 l/min (mean 5.93 ± 1.55 l/min. The bias and limits of agreement between COPAC and COAP for unequal numbers of replicates was 0.02 ± 2.92 l/min. The percentage error between COPAC and COAP was 49.3%. The bias between percentage changes in COPAC (ΔCOPAC and percentage changes in COAP (ΔCOAP for consecutive measurements was -0.70% ± 32.28%. COPAC and COAP showed a Pearson correlation coefficient of 0.58 (p PAC and ΔCOAP was 0.46 (p Conclusion Although the COAP algorithm shows a minimal bias with COPAC over a wide range of values in an inhomogeneous group of critically ill patients, the scattering of the data remains relative wide. Therefore, the used algorithm (V 1.03 failed to

  11. Long-Run Impact of Increased Wage Pressure

    DEFF Research Database (Denmark)

    Hansen, Claus Thustrup

    1999-01-01

    An unanticipated permanent increase in wage pressure is analyzed in a dynamic general-equilibrium model combining standard theory of capital accumulation and monopolistic wage setting. The long-run (steady-state) implications are identical percentage reduction in employment, consumption......, and capital stock whereas wages and the real interest rate are unchanged. The reduction in employment on impact is larger than the steady-state reduction whereas wages rise and the real interest rate declines on impact...

  12. Does high altitude increase risks of the elderly patients with coronary artery disease?

    Institute of Scientific and Technical Information of China (English)

    Tian-Yi Wu; Zhong-Yan Zhan; Qin-Li Wu; Suo-Lung Baomu; Yu-Ling Jie; Min Sun

    2009-01-01

    Objective To assess the effect of altitude hypoxia on the elderly patients with coronary artery disease (CAD). Methods Three subject groups were surveyed during their train trip on the highest railroad--the Qinghai-Tibet Railway: 22 elderly individuals with documented CAD, 20 healthy elderly controls, and 20 healthy young controls, all of whom from Beijing near the sea level (76 m). Survey questions addressed clinical features of their healthy conditions and aspects of their coronary disease. The baseline study was performed at Xining at an altitude of 2261 m, and then during acute exposure to altitudes of 2808 m, 4768m, 5072 m and 4257 m by train for 24 hours. Resting pulse rate, blood pressure, oxygen saturation, electrocardiograph (ECG), and cardiac work estimated by the heart rate-blood pressure double product were obtained five times in each subject at different altitudes. Results On arrival to altitudes between 4768 m and 5072 m, the older passengers, especially those with preexisting coronary disease, had higher HR, higher BP, and lower SaO2, as well as more frequent abnormalities on ECG, as compared to the younger healthy subjects. As compared with the healthy elderly controls, incomplete right bundle branch block, left ventricular hypertrophy, and ST segment depression were more frequently seen in the elderly coronary patients (P<0.01). Cardiac work in group 1 was increased by 13% 12 hours after arrival to altitudes between 2808 m and 5072 m. Oxygen saturation decreased significantly with the altitude increasing by train ascent but improved after inhalation of oxygen. Most of the older subjects tolerated their sojourn at high altitude well except one who developed angina repeatedly with a significant ST segment depression. Conclusions Coronary events and ECG signs of myocardial ischemia are rare in elderly individuals with CAD who travel from sea level to moderate altitudes of 1500m to 2800 m. Patients with CAD who are well compensated at sea level

  13. Percutaneous transluminal renal angioplasty with stent is effective for blood pressure control and renal function improvement in atherosclerotic renal artery stenosis patients

    Institute of Scientific and Technical Information of China (English)

    LIAO Chuan-jun; YANG Bao-zhong; WANG Zhong-gao

    2012-01-01

    Background Percutaneous transluminal renal angioplasty with stent is an effective procedure for atherosclerotic renal artery stenosis.However,the decision to perform this procedure has recently raised considerable debate.The aim of this study was to assess the effects of percutaneous transluminal renal angioplasty with stent in atherosclerotic renal artery stenosis patients,especially as it relates to blood pressure control and renal function improvement.Methods A retrospective analysis was made of the clinical data from 125 atherosclerotic renal artery stenosis patients who underwent percutaneous transluminal renal angioplasty from July 2004 to June 2008 in the Department of Vascular Surgery of Beijing Chaoyang Hospital.We compared blood pressure,number of oral antihypertensive medications,and renal function changes pre and post-procedure at 24 months follow-up.Results A total of 125 atherosclerotic renal artery stenosis patients underwent percutaneous transluminal renal angioplasty and 143 stents were placed.At 24 months follow-up,both systolic and diastolic blood pressure and the number of oral antihypertensive medications were significantly reduced (P <0.05).Overall,the estimated glomerular filtration rate did not change significantly (P >0.05); however,a significant increase in estimated glomerular filtration rate was observed in the subgroup of patients with a lower baseline estimated glomerular filtration rate and in the subgroup of patients with bilateral renal artery stenosis (P <0.05).Conclusion Percutaneous transluminal renal angioplasty is a safe procedure for atherosclerotic renal artery stenosis patients,providing a significant improvement in blood pressure control and reduction in the number of oral antihypertensive medications.

  14. Correlation of the intraocular pressure with increased intracranial pressure in rabbits

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    Eskandari H

    2000-08-01

    Full Text Available Although measurement of intracranial pressure by noninvasive methods has been suggested, but mainly invasive methods are used for this purpose-Increase in episcleral venous pressure can be expected to result in a linear increase in intraocular pressure. Congested oculat veins with capillary leakage and hemorrhage are seen when the ICP is increased, thus theoretically measurement of intraocular pressure can be a procedure for estimation of the ICP. This study was performed to find whether there is andy relationship between intraocular pressure and ICP, so we used 12 albino rabbits in two divided groups. Our study was not designed to elucidate the mechanism of change but merely to record any changes observed. All measures except an increase in ICP were applied on the test group as well as on the control group. After general anesthesia with the combination of ketamin, rampune, and pentobarbital a burr hole was made in the lambda region of the skull and a cannula was placed in the subdural space. The ICP in the test group increased up to 15 mmHg and was constant throughout the experiment. Intraocular pressure was measured by Schiotz tonometers afte general anesthesia, after cannulation of the skull, and immediately after increasing the ICP which was repated in 15 minutes interval for 4 hours. There was no statistical difference between the two groups (P:0.997 . results show that neither cannulation nor general anesthesia for 4 hours produce alteration in IOP in the control group nor increasing of the ICP to level of 15 mmHg produces any alteration in IOP on the test group.

  15. Low frequency component in systolic arterial pressure variability in patients with persistent atrial fibrillation.

    Science.gov (United States)

    Mainardi, Luca; Corino, Valentina; Belletti, Sebastiano; Terranova, Paolo; Lombardi, Federico

    2009-12-03

    Atrial fibrillation (AF) is a common arrhythmia characterized by irregular ventricular response. During AF, beat-to-beat variability of arterial pressure (AP) is increased because of continuous changes in filling time, stroke volume and contractility. Only a few studies have analyzed short-term AP variability during AF but they were mainly focused on the effects of respiration. We therefore analyzed short-term systolic (S), diastolic (D) and mean (M) AP variability by autoregressive method and an FFT-based spectral estimation (Welch periodogram) in 26 patients with persistent AF before and after restoration of sinus rhythm by electrical cardioversion. A low frequency (LF) component (central frequency 0.07+/-0.02 Hz, mean+/-standard deviation) of SAP variability was observed in 23 out of 26 patients during AF. Frequency analysis of DAP and MAP also showed a LF component with a central frequency of 0.08+/-0.03 Hz (20 patients) and 0.07+/-0.03 Hz (25 patients), respectively. After recovery of sinus rhythm, we found significant reduction in mean SAP, DAP and MAP variability in all frequency bands. Squared coherence between SAP and heart rate variability after recovery of sinus rhythm revealed a weak and strong coupling within, respectively, LF and HF frequency bands. These data indicate that in patients with AF, in spite of an absence of rhythmical oscillation in RR interval time series, it is possible to observe a LF component in SAP, DAP and MAP variability signals. These 0.1 Hz fluctuations reflect the influence of the sympathetic fibres acting on the cardiovascular system.

  16. Arterial waveform analysis.

    Science.gov (United States)

    Esper, Stephen A; Pinsky, Michael R

    2014-12-01

    The bedside measurement of continuous arterial pressure values from waveform analysis has been routinely available via indwelling arterial catheterization for >50 years. Invasive blood pressure monitoring has been utilized in critically ill patients, in both the operating room and critical care units, to facilitate rapid diagnoses of cardiovascular insufficiency and monitor response to treatments aimed at correcting abnormalities before the consequences of either hypo- or hypertension are seen. Minimally invasive techniques to estimate cardiac output (CO) have gained increased appeal. This has led to the increased interest in arterial waveform analysis to provide this important information, as it is measured continuously in many operating rooms and intensive care units. Arterial waveform analysis also allows for the calculation of many so-called derived parameters intrinsically created by this pulse pressure profile. These include estimates of left ventricular stroke volume (SV), CO, vascular resistance, and during positive-pressure breathing, SV variation, and pulse pressure variation. This article focuses on the principles of arterial waveform analysis and their determinants, components of the arterial system, and arterial pulse contour. It will also address the advantage of measuring real-time CO by the arterial waveform and the benefits to measuring SV variation. Arterial waveform analysis has gained a large interest in the overall assessment and management of the critically ill and those at a risk of hemodynamic deterioration.

  17. Ex Vivo and in Silico Study of Human Common Carotid Arteries Pressure Response in Physiological and Inverted State

    Science.gov (United States)

    Piechna, A.; Cieślicki, K.; Lombarski, L.; Ciszek, B.

    2015-02-01

    Arterial walls are a multilayer structures with nonlinear material characteristics. Furthermore, residual stresses exist in unloaded state (zero-pressure condition) and they affect arterial behavior. To investigate these phenomena a number of theoretical and numerical studies were performed, however no experimental validation was proposed and realized yet. We cannot get rid of residual stresses without damaging the arterial segment. In this paper we propose a novel experiment to validate a numerical model of artery with residual stresses. The inspiration for our study originates from experiments made by Dobrin on dogs' arteries (1999). We applied the idea of turning the artery inside out. After such an operation the sequence of layer is reversed and the residual stresses are re-ordered. We performed several pressure-inflation tests on human Common Carotid Arteries (CCA) in normal and inverted configurations. The nonlinear responses of arterial behavior were obtained and compared to the numerical model. Computer simulations were carried out using the commercial software which applied the finite element method (FEM). Then, these results were discussed.

  18. End-tidal arterial CO2 partial pressure gradient in patients with severe hypercapnia undergoing noninvasive ventilation

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    Defilippis V

    2013-06-01

    Full Text Available Vito Defilippis,1 Davide D’Antini,2 Gilda Cinnella,2 Michele Dambrosio,2 Fernando Schiraldi,3 Vito Procacci1 1Emergency Department, Riuniti Hospital, 2Department of Anaesthesiology and Intensive Care, University of Foggia, Foggia, 3Emergency Department, San Paolo Hospital, Naples, Italy Background: Patients with severe hypercapnia represent a particularly serious condition in an emergency department (ED, requiring immediate attention. Noninvasive ventilation (NIV is an integral part of the treatment for acute respiratory failure. The present study aimed to validate the measurement of end-tidal CO2 (EtCO2 as a noninvasive technique to evaluate the effectiveness of NIV in acute hypercapnic respiratory failure. Methods: Twenty consecutive patients admitted to the ED with severe dyspnea were enrolled in the study. NIV by means of bilevel positive airway pressure, was applied to the patients simultaneously with standard medical therapy and continued for 12 hours; the arterial blood gases and side-stream nasal/oral EtCO2 were measured at subsequent times: T0 (admission to the ED, T1h (after 1 hour, T6h (after 6 hours, and T12h (after 12 hours during NIV treatment. Results: The arterial CO2 partial pressure (PaCO2–EtCO2 gradient decreased progressively, reaching at T6h and T12h values lower than baseline (P < 0.001, while arterial pH increased during the observation period (P < 0.001. A positive correlation was found between EtCO2 and PaCO2 values (r = 0.89, P < 0.001 at the end of the observation period. Conclusion: In our hypercapnic patients, the effectiveness of the NIV was evidenced by the progressive reduction of the PaCO2–EtCO2 gradient. The measurement of the CO2 gradient could be a reliable method in monitoring the effectiveness of NIV in acute hypercapnic respiratory failure in the ED. Keywords: arterial end-tidal CO2 gradient, noninvasive ventilation, bilevel positive airway pressure, acute respiratory failure

  19. Effect of beta-1-blocker, nebivolol, on central aortic pressure and arterial stiffness in patients with essential hypertension

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    Radhika Soanker

    2012-01-01

    Conclusion: Nebivolol 5 mg demonstrated antihypertensive efficacy in patients with essential hypertension by reducing not only peripheral brachial pressures, but also significantly reducing central aortic pressures, augmentation index, and carotid femoral pulse wave velocity, which is the marker of arterial stiffness.

  20. Blood pressure-independent hypotrophy of the heart, kidneys and conduit arteries after 7-nitroindazole administration to Wistar rats from the prenatal period to adulthood.

    Science.gov (United States)

    Kristek, F; Malekova, M; Ondrias, K; Cacanyiova, S

    2013-02-01

    The aim of this study was to investigate the long-term effects of 7-nitroindazole on the heart, kidneys, thoracic aorta, and carotid arteries from the progeny of mothers that had been treated with 7-nitroindazole (7NI) (10 mg/kg/day in drinking water) during gestation and nursing. The offspring were also treated with 7NI (10 mg/kg/day in drinking water) until 10 weeks of age. Mean arterial pressure (BP) was measured by tail-cuff plethysmography starting at 4 weeks of age. After perfusion fixation with glutaraldehyde at 120 mmHg, the heart and kidneys were weighed and the thoracic aorta and carotid arteries were processed for morphological investigation. The BP and body weight of treated rats did not differ from age-matched control rats during the course of the experiment. In the experimental group, at the end of the experiment, the heart weight/body weight and kidney weight/body weight ratios were decreased. In addition, the wall thickness (intima + media), cross sectional area (intima + media), and wall thickness/inner diameter ratio were significantly decreased in both the thoracic aorta and carotid arteries without a change in the inner vessel diameter. Circumferential wall tension was increased in both arteries. The data clearly indicate that long-term inhibition of neuronal nitric oxide (NO) synthase with the specific inhibitor 7NI evokes BP-independent hypotrophy of the heart, kidneys, and conduit arterial walls in normotensive Wistar rats.

  1. Oscillometric blood pressure measurement: a simple method in screening for peripheral arterial disease

    DEFF Research Database (Denmark)

    Mehlsen, Jesper; Wiinberg, Niels; Bruce, Christopher

    2008-01-01

    Blood pressure at the ankle level is a reliable indicator of peripheral arterial disease (PAD) and the ankle brachial index (ABI) is a useful non-invasive screening tool for the early detection of atherosclerosis. In the first part of the study, systolic blood pressures obtained by oscillometry......, the oscillometry showed a positive predictive value of 47%. The presence of PAD was significantly correlated to exercise related leg pain, a diagnosis of hypertension and smoking, whereas no correlation could be found with a diagnosis of heart disease, stroke, or with the presence of diabetes. The prevalence...... of PAD was sufficiently high in subjects over the age of 60 years to warrant screening. The ankle brachial index based on measurements with an oscillometric device was shown reliable in the exclusion of PAD, thereby fulfilling an important criterion for the use in screening....

  2. Role of the vestibular system in the arterial pressure response to parabolic-flight-induced gravitational changes in human subjects.

    Science.gov (United States)

    Iwata, Chihiro; Abe, Chikara; Tanaka, Kunihiko; Morita, Hironobu

    2011-05-16

    Arterial pressure (AP) is known to fluctuate during parabolic-flight-induced gravitational changes in human subjects, increasing during hypergravity and decreasing during microgravity. In this study, we examined whether the vestibular system participates in the AP response to the gravitational changes induced by parabolic flight in human subjects. Eight subjects performed parabolic flights in a supine position as their AP was measured. Their vestibular inputs during the gravitational changes were reversibly masked by artificial electrical stimulation (galvanic vestibular stimulation, GVS). The AP responses during the parabolas were then compared between the GVS-off and GVS-on conditions. AP increased during hypergravity and decreased during microgravity. The AP responses at the onset of hypergravity and microgravity were abolished by GVS. These results indicate that the vestibular system elicits pressor and depressor responses during parabolic-flight-induced hypergravity and microgravity, respectively.

  3. Increased metabolite levels of glycolysis and pentose phosphate pathway in rabbit atherosclerotic arteries and hypoxic macrophage.

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    Atsushi Yamashita

    Full Text Available AIMS: Inflammation and possibly hypoxia largely affect glucose utilization in atherosclerotic arteries, which could alter many metabolic systems. However, metabolic changes in atherosclerotic plaques remain unknown. The present study aims to identify changes in metabolic systems relative to glucose uptake and hypoxia in rabbit atherosclerotic arteries and cultured macrophages. METHODS: Macrophage-rich or smooth muscle cell (SMC-rich neointima was created by balloon injury in the iliac-femoral arteries of rabbits fed with a 0.5% cholesterol diet or a conventional diet. THP-1 macrophages stimulated with lipopolysaccharides (LPS and interferon-γ (INFγ were cultured under normoxic and hypoxic conditions. We evaluated comprehensive arterial and macrophage metabolism by performing metabolomic analyses using capillary electrophoresis-time of flight mass spectrometry. We evaluated glucose uptake and its relationship to vascular hypoxia using (18F-fluorodeoxyglucose ((18F-FDG and pimonidazole, a marker of hypoxia. RESULTS: The levels of many metabolites increased in the iliac-femoral arteries with macrophage-rich neointima, compared with those that were not injured and those with SMC-rich neointima (glycolysis, 4 of 9; pentose phosphate pathway, 4 of 6; tricarboxylic acid cycle, 4 of 6; nucleotides, 10 of 20. The uptake of (18F-FDG in arterial walls measured by autoradiography positively correlated with macrophage- and pimonidazole-immunopositive areas (r = 0.76, and r = 0.59 respectively; n = 69 for both; p<0.0001. Pimonidazole immunoreactivity was closely localized with the nuclear translocation of hypoxia inducible factor-1α and hexokinase II expression in macrophage-rich neointima. The levels of glycolytic (8 of 8 and pentose phosphate pathway (4 of 6 metabolites increased in LPS and INFγ stimulated macrophages under hypoxic but not normoxic condition. Plasminogen activator inhibitor-1 protein levels in the supernatant were closely

  4. Obstructive sleep apnea is associated with increased arterial stiffness in severe obesity.

    Science.gov (United States)

    Seetho, Ian W; Parker, Robert J; Craig, Sonya; Duffy, Nick; Hardy, Kevin J; Wilding, John P H

    2014-12-01

    Obstructive sleep apnea is associated with obesity and metabolic syndrome, leading to greater cardiovascular risk. Severely obese patients with obstructive sleep apnea may still be at risk of adverse health outcomes, even without previous cardiovascular disease. Pulse wave analysis non-invasively measures peripheral pulse waveforms and derives measures of haemodynamic status, including arterial stiffness, augmentation pressure and subendocardial viability ratio. We hypothesized that the presence of obstructive sleep apnea in severe obesity, even in the absence of an antecedent history of cardiovascular disease, would affect measurements derived from pulse wave analysis. Seventy-two severely obese adult subjects [obstructive sleep apnea 47 (body mass index 42 ± 7 kg m(-2) ), without obstructive sleep apnea (non-OSA) 25 (body mass index 40 ± 5 kg m(-2) )] were characterised using anthropometric, respiratory and cardio-metabolic parameters. Groups were similar in age, body mass index and gender. More subjects with obstructive sleep apnea had metabolic syndrome [obstructive sleep apnea 60%, without obstructive sleep apnea (non-OSA) 12%]. Those with obstructive sleep apnea had greater arterial stiffness, augmentation pressure and decreased subendocardial viability ratio (all P cardiovascular risk independently of metabolic abnormalities. The presence of obstructive sleep apnea in severe obesity identifies a group at high cardiovascular risk; clinicians should ensure that risk factors are managed appropriately in this group whether or not treatment of obstructive sleep apnea is offered or accepted by patients.

  5. Effects of three days of dry immersion on muscle sympathetic nerve activity and arterial blood pressure in humans.

    Science.gov (United States)

    Iwase, S; Sugiyama, Y; Miwa, C; Kamiya, A; Mano, T; Ohira, Y; Shenkman, B; Egorov, A I; Kozlovskaya, I B

    2000-03-15

    The present study was performed to determine how sympathetic function is altered by simulated microgravity, dry immersion for 3 days, and to elucidate the mechanism of post-spaceflight orthostatic intolerance in humans. Six healthy men aged 21-36 years old participated in the study. Before and after the dry immersion, subjects performed head-up tilt (HUT) test to 30 degrees and 60 degrees (5 min each) with recordings of muscle sympathetic nerve activity (MSNA, by microneurography), electrocardiogram, and arterial blood pressure (Finapres). Resting MSNA was increased after dry immersion from 23.7+/-3.2 to 40.9+/-3.0 bursts/min (p<0.005) without significant changes in resting heart rate (HR). MSNA responsiveness to orthostasis showed no significant difference but HR response was significantly augmented after dry immersion (p<0. 005). A significant diastolic blood pressure fall at 5th min of 60 degrees HUT was observed in five orthostatic tolerant subjects despite enough MSNA discharge after dry immersion. A subject suffered from presyncope at 2 min after 60 degrees HUT. He showed gradual blood pressure fall 10 s after 60 degrees HUT with initially well-maintained MSNA response and then with a gradually attenuated MSNA, followed by a sudden MSNA withdrawal and abrupt blood pressure drop. In conclusion, dry immersion increased MSNA without changing MSNA response to orthostasis, and resting HR, while increasing the HR response to orthostasis. Analyses of MSNA and blood pressure changes in orthostatic tolerant subjects and a subject with presyncope suggested that not only insufficient vasoconstriction to sympathetic stimuli, but also a central mechanism to induce a sympathetic withdrawal might play a role in the development of orthostatic intolerance after microgravity exposure.

  6. A pressão arterial está sendo medida? Is the blood pressure being measured?

    Directory of Open Access Journals (Sweden)

    Débora C. Alavarce

    2000-03-01

    Full Text Available A medida da pressão arterial faz parte do exame físico e deve ser realizada em toda consulta médica. Para avaliar se a pressão arterial é medida nas consultas médicas, foram consultados 500 prontuários de pacientes de primeira consulta ambulatorial, sendo 335 (67% provenientes de clínicas médicas e cirúrgicas e 165 (33% das clínicas ginecológica e obstétrica. A pressão arterial foi anotada em 39% das consultas realizadas (135±32/85±19 mm Hg, sendo que em 11% destas anotações a pressão diastólica estava acima de 90 mm Hg. Em relação ao diagnóstico prévio de hipertensão arterial verificou-se que: a em 62% dos prontuários não havia esta informação; b 20% referiram ter hipertensão, e em 79% destes a pressão arterial foi anotada; e c 18% referiram não ter hipertensão e 46% destes tiveram registro da pressão arterial. Portanto, a maior parte dos pacientes não teve sua pressão arterial anotada.The blood pressure measure is part of the physical exam and it should be accomplished in every medical consultation. To verify the blood pressure measured in the accomplished medical consultations record of first they were consulted it consults 500 patient's ambulatorial being 335 (67% coming of medical and surgical clinics and 165 (33% of the gynecological and obstetric clinics. The blood pressure was written down in 39% of the accomplished consultations (135+32 mm Hg 85+19 mm Hg, and 11% of this annotations the pressure diastólica was above 90 mm Hg. In relation to the previous diagnosis of hypertension it was verified that: a in 62% of the records there was not this information; b 20% referred to have hypertension, and in 79% of these the arterial pressure was scored; and c 18% referred not to have hypertension and 46% of these had registration of the arterial pressure. Therefore, most of the patients didn't have its logged arterial pressure.

  7. Arterial blood pressure oscillation after active standing up in kidney transplant recipients.

    Science.gov (United States)

    Gerhardt, U; Schäfer, M; Hohage, H

    2000-04-12

    Dynamic arterial blood pressure (FINAPRES) response to active standing up, normally consisting of initial rise, fall and recovery above the baseline (overshoot), was compared with the early steady-state arterial blood pressure level to measure sympathetic vasomotor function in healthy subjects [group 1: n=50, 10 female subjects, age 51+/-2.5 years; weight 78+/-2.3 kg; height 174+/-1.4 cm (mean+/-standard error of the mean)] and in kidney transplant recipients under basal (group 2a: n=50, age 51.7+/-1.7 years; weight 77+/-2.1 kg; height 174+/-1.5 cm) and under high (group 2b: same subjects as in group 2a) cyclosporine A whole blood levels. Furthermore, baroreflex sensitivity and the activity of the generating compounds of the sympathetic nervous systems (Mayer waves) were measured. Systolic and diastolic overshoot values did not differ statistically significant in the present study. In the control subjects, a systolic overshoot of 15.4+/-2.7 mmHg and a diastolic overshoot of 15.2+/-2 mmHg was detected. The systolic overshoot disappeared in 57% of group 2a (-7.1+/-2.7 mmHg; P<0.001) and in 50% of group 2b recipients (-8.0+/-2.7 mmHg; P<0.001). Systolic early steady-state level was not lower in kidney transplant recipients before cyclosporine (baseline+2 mmHg) intake, but after cyclosporine administration (baseline-3 mmHg; controls: baseline+3 mmHg; P<0.05). There was a strong association between the overshoot and steady-state levels (P for chi(2)<0.001, n=150). Overshoot of group 1 levels (r=0.428; P<0.01) and group 2 levels (r=0.714; P<0. 001) correlated to their respective steady-state blood pressure. Furthermore, recipients had reduced baroreceptor sensitivities estimated by sequence analysis as compared to controls (10+/-1 ms/mmHg vs. 7.5+/-1.4 ms/mmHg; P<0.05). Mayer waves amplitudes of the heart rate spectrum were elevated statistically significant in renal transplant recipients (44.4+/-0.2 vs. 43.8+/-2.2 A.U.). In conclusion, baroreceptor reflex

  8. Neural reflex regulation of arterial pressure in pathophysiological conditions: interplay among the baroreflex, the cardiopulmonary reflexes and the chemoreflex

    Directory of Open Access Journals (Sweden)

    E.C. Vasquez

    1997-04-01

    Full Text Available The maintenance of arterial pressure at levels adequate to perfuse the tissues is a basic requirement for the constancy of the internal environment and survival. The objective of the present review was to provide information about the basic reflex mechanisms that are responsible for the moment-to-moment regulation of the cardiovascular system. We demonstrate that this control is largely provided by the action of arterial and non-arterial reflexes that detect and correct changes in arterial pressure (baroreflex, blood volume or chemical composition (mechano- and chemosensitive cardiopulmonary reflexes, and changes in blood-gas composition (chemoreceptor reflex. The importance of the integration of these cardiovascular reflexes is well understood and it is clear that processing mainly occurs in the nucleus tractus solitarii, although the mechanism is poorly understood. There are several indications that the interactions of baroreflex, chemoreflex and Bezold-Jarisch reflex inputs, and the central nervous system control the activity of autonomic preganglionic neurons through parallel afferent and efferent pathways to achieve cardiovascular homeostasis. It is surprising that so little appears in the literature about the integration of these neural reflexes in cardiovascular function. Thus, our purpose was to review the interplay between peripheral neural reflex mechanisms of arterial blood pressure and blood volume regulation in physiological and pathophysiological states. Special emphasis is placed on the experimental model of arterial hypertension induced by N-nitro-L-arginine methyl ester (L-NAME in which the interplay of these three reflexes is demonstrable

  9. Earliest effects of sudden occlusions on pressure profiles in selected locations of the human systemic arterial system

    Science.gov (United States)

    Majka, Marcin; Gadda, Giacomo; Taibi, Angelo; Gałązka, Mirosław; Zieliński, Piotr

    2017-03-01

    We have developed a numerical simulation method for predicting the time dependence (wave form) of pressure at any location in the systemic arterial system in humans. The method uses the matlab-Simulink environment. The input data include explicitly the geometry of the arterial tree, treated up to an arbitrary bifurcation level, and the elastic properties of arteries as well as rheological parameters of blood. Thus, the impact of anatomic details of an individual subject can be studied. The method is applied here to reveal the earliest stages of mechanical reaction of the pressure profiles to sudden local blockages (thromboses or embolisms) of selected arteries. The results obtained with a purely passive model provide reference data indispensable for studies of longer-term effects due to neural and humoral mechanisms. The reliability of the results has been checked by comparison of two available sets of anatomic, elastic, and rheological data involving (i) 55 and (ii) 138 arterial segments. The remaining arteries have been replaced with the appropriate resistive elements. Both models are efficient in predicting an overall shift of pressure, whereas the accuracy of the 55-segment model in reproducing the detailed wave forms and stabilization times turns out dependent on the location of the blockage and the observation point.

  10. Arterial pressure variations as parameters of brain perfusion in response to central blood volume depletion and repletion

    Directory of Open Access Journals (Sweden)

    Anne-Sophie G.T. Bronzwaer

    2014-04-01

    Full Text Available Rationale:A critical reduction in central blood volume (CBV is often characterized by hemodynamic instability. Restoration of a volume deficit may be established by goal-directed fluid therapy guided by respiration-related variation in systolic- and pulse pressure (SPV and PPV. Stroke volume index (SVI serves as a surrogate end-point of a fluid challenge but tissue perfusion itself has not been addressed. Objective: To delineate the relationship between arterial pressure variations, SVI and regional brain perfusion during CBV depletion and repletion in spontaneously breathing volunteers. Methods: This study quantified in 14 healthy subjects (11 male the effects of CBV depletion (by 30 and 70 degrees passive head-up tilt (HUT and a fluid challenge (by tilt back on CBV (thoracic admittance, mean middle cerebral artery (MCA blood flow velocity (Vmean, SVI, cardiac index (CI , PPV and SPV. Results: PPV (103±89%, p< 0.05 and SPV (136±117%, p< 0.05 increased with progression of central hypovolemia manifested by a reduction in thoracic admittance (11±5%, p< 0.001, SVI (28±6%, p< 0.001, CI (6±8%, p< 0.001 and MCAVmean (17±7%, p< 0.05 but not in arterial pressure. The reduction in MCAVmean correlated to the fall in SVI (R2=0.52, p< 0.0001 and inversely to PPV and SPV (R2=0.46 (p< 0.0001 and R2=0.45 (p< 0.0001, respectively. PPV and SPV predicted a ≥15% reduction in MCAVmean and SVI with comparable sensitivity (67%/ 67% vs. 63%/ 68% respectively and specificity (89%/94% vs. 89%/94%, respectively. A rapid fluid challenge by tilt-back restored all parameters to baseline values within one minute. Conclusion: In spontaneously breathing subjects, a reduction in MCAVmean was related to an increase in PPV and SPV during graded CBV depletion and repletion. Specifically, PPV and SPV predicted changes in both SVI and MCAVmean with comparable sensitivity and specificity, however the predictive value is limited in spontaneously breathing subjects.

  11. Hypoxia stimulates prostacyclin synthesis in newborn pulmonary artery endothelium by increasing cyclooxygenase-1 protein.

    Science.gov (United States)

    North, A J; Brannon, T S; Wells, L B; Campbell, W B; Shaul, P W

    1994-07-01

    In newborn lambs, pulmonary prostacyclin (PGI2) production increases acutely in response to low oxygen. We tested the hypothesis that decreased oxygenation directly stimulates PGI2 synthesis in arterial segments and cultured endothelial cells from newborn lamb intrapulmonary arteries. In segments studied at PO2 of 680 mm Hg, the synthesis of PGI2 exceeded prostaglandin E2 (PGE2) by 73%. Endothelium removal lowered PGI2 by 77% and PGE2 by 66%. At low oxygen tension (PO2, 40 mm Hg), PGI2 and PGE2 synthesis rose by 96% and 102%, respectively. Similarly, in endothelial cells studied at PO2 of 680 mm Hg, the synthesis of PGI2 exceeded PGE2 by 50%, and at low oxygen tension both PGI2 and PGE2 increased (89% and 64%, respectively). Endothelial cell PGI2 synthesis maximally stimulated by bradykinin, A23187, or arachidonic acid was also increased at low PO2 by 50%, 66%, and 48%, respectively. PGE2 synthesis was similarly altered, increasing by 33%, 37%, and 41%, respectively. In contrast, lowering oxygen had minimal effect on PGI2 and PGE2 synthesis with exogenous PGH2, which is the product of cyclooxygenase. Immunoblot analyses revealed that there was a 2.6-fold greater abundance of cyclooxygenase-1 protein at PO2 of 40 versus 680 mm Hg, and the increase at lower oxygen tension was inhibited by cycloheximide. The cyclooxygenase-2 isoform was not detected. Thus, attenuated oxygenation directly stimulates PGI2 and PGE2 synthesis in intrapulmonary arterial segments and endothelial cells from newborn lambs. This process is due to enhanced cyclooxygenase activity related to increased abundance of the cyclooxygenase-1 protein, and this effect may be due to increased synthesis of the enzyme protein.

  12. The Intracranial Volume Pressure Response in Increased Intracranial Pressure Patients: Clinical Significance of the Volume Pressure Indicator

    Science.gov (United States)

    2016-01-01

    Background For patients suffering from primary brain injury, monitoring intracranial pressure alone is not enough to reflect the dynamic intracranial condition. In our previous study, a segment of the pressure-volume curve can be expressed by the parabolic regression model with single indicator “a”. The aim of this study is to evaluate if the indicator “a” can reflect intracranial conditions. Methods Patients with traumatic brain injury, spontaneous intracranial hemorrhage, and/or hydrocephalus who had external ventricular drainage from January 2009 to February 2010 were included. The successive volume pressure response values were obtained by successive drainage of cerebral spinal fluid from intracranial pressure 20–25 mm Hg to 10 mm Hg. The relationship between withdrawn cerebral spinal fluid volume and intracranial pressure was analyzed by the parabolic regression model with single parameter “a”. Results The overall mean for indicator “a” was 0.422 ± 0.046. The mean of “a” in hydrocephalus was 0.173 ± 0.024 and in severe intracranial mass with slender ventricle, it was 0.663 ± 0.062. The two extreme intracranial conditions had a statistical significant difference (phydrocephalus. Brain computed tomography should be performed early if a rapid elevation of indicator “a” is detected, as it can reveal some ongoing intracranial pathology prior to clinical deterioration. Increased intracranial pressure was frequently observed in patients with intracranial pathology. The progression can be differentiated using the pattern of the volume pressure indicator. PMID:27723794

  13. A mysterious blood pressure increase in a drilling Naval reservist.

    Science.gov (United States)

    Wettach, George E; Falvey, Shelley G

    2002-06-01

    This is a case report of a reservist who presented for a physical examination with hypertension. It was discovered that the reservist was unknowingly taking large doses of Ephedra sinica, or ma huang, a Chinese herbal supplement, for body-building. One of the ingredients in ma huang is ephedrine, an active alpha- and beta-adrenergic stimulant that produces increases in heart rate, blood pressure, and cardiac output. Ma huang has been reported to cause hypertension, hepatitis, nephrolithiasis, and sudden death in healthy, normotensive people. Ma huang will produce a positive urinary drug screen for stimulants and can be a drug of abuse. A recommendation is made to screen for dangerous supplement use before physical readiness training and to stop the supplement for 1 month before beginning any exercise program.

  14. Changes in arterial blood pressure elicited by severe passive heating at rest is associated with hyperthermia-induced hyperventilation in humans.

    Science.gov (United States)

    Fujii, Naoto; Ichinose, Masashi; Honda, Yasushi; Tsuji, Bun; Watanabe, Kazuhito; Kondo, Narihiko; Nishiyasu, Takeshi

    2013-01-01

    The arterial blood pressure and ventilatory responses to severe passive heating at rest varies greatly among individuals. We tested the hypothesis that the increase in ventilation seen during severe passive heating of resting humans is associated with a decrease in arterial blood pressure. Passive heating was performed on 18 healthy males using hot water immersion to the level of the iliac crest and a water-perfused suit. We then divided the subjects into two groups: MAP(NOTINC) (n = 8), whose mean arterial blood pressure (MAP) at the end of heating had increased by ≤3 mmHg, and MAP(INC) (n = 10), whose MAP increased by >3 mmHg. Increases in esophageal temperature (T (es)) elicited by the heating were similar in the two groups (+2.3 ± 0.3 vs. +2.4 ± 0.4 °C). Early during heating (increase in T (es) was ventilation ([Formula: see text]), and end-tidal CO(2) pressure ([Formula: see text]) were similar between the groups. However, during the latter part of heating (increase in T (es) was ≥1.5 °C), the increase in [Formula: see text] and decrease in [Formula: see text] were significantly greater or tended to be greater, while the increase in MAP was significantly smaller in MAP(NOTINC) than MAP(INC). Among all subjects, heating-induced changes in [Formula: see text] significantly and negatively correlated with heating-induced changes in MAP during the latter part of heating (r = -0.52 to -0.74, P passive heating can be explained by the magnitude of hyperthermia-induced hyperventilation.

  15. Comparison of the effects of antihypertensive agents on central blood pressure and arterial stiffness in isolated systolic hypertension.

    Science.gov (United States)

    Mackenzie, Isla S; McEniery, Carmel M; Dhakam, Zahid; Brown, Morris J; Cockcroft, John R; Wilkinson, Ian B

    2009-08-01

    Isolated systolic hypertension is an important risk factor for cardiovascular disease and results primarily from elastic artery stiffening. Although various drug therapies are used to lower peripheral blood pressure (BP) in patients with isolated systolic hypertension, the effects of the 4 major classes of antihypertensive agents on central BP, pulse pressure (PP) amplification, and arterial stiffness in this condition are not clear. Fifty-nine patients over the age of 60 years with untreated isolated systolic hypertension (systolic BP > or =140 mm Hg and diastolic BP hypertension, the choice of therapy may be influenced by these findings in the future.

  16. Dynamic Changes of Pulmonary Arterial Pressure and Ductus Arteriosus in Human Newborns From Birth to 72 Hours of Age

    OpenAIRE

    2016-01-01

    Abstract Normal pulmonary artery pressure and pulmonary hypertension assessment of newborns is rarely reported. The aim of the study is to explore dynamic changes of pulmonary arterial pressure and ductus arteriosus in human newborns from birth to 72 h of age with echocardiography. A total of 76 cases of normal newborns were prospectively detected by echocardiography after birth of 2 h, 6 h, 12 h, 24 h, 48 h, and 72 h, respectively. Ductus arteriosus diameter, blood shunt direction, blood flo...

  17. Concentration-dependent effects of cocaine on monoamine-induced constriction of cannulated, pressurized cerebral arteries from fetal sheep.

    Science.gov (United States)

    Schreiber, M D; Madden, J A; Covert, R F; Hershenson, M B; Torgerson, L J

    1995-01-01

    Drugs, such as cocaine, which may alter monoamine neurotransmitter responsiveness, could adversely affect the regulation of cerebral vasculature. Cocaine exhibits at least two mechanisms that may alter vascular responsiveness: synaptic uptake inhibition, which may augment response to stimulation, and Na+ channel inhibition, which may attenuate response. To help elicit the concentration-dependent effects of cocaine, the effects of cocaine on monoamine neurotransmitter responsiveness were studied in vitro on fetal sheep cerebral arteries (120 days gestation). The changes in diameter of segments of cannulated, pressurized fetal sheep cerebral artery were measured with a videomicroscaler system. Cumulative concentration-response curves (10(-10) to 10(-4)M) were generated for two monoamines, norepinephrine and serotonin, alone and in the presence of cocaine (10(-5) or 10(-4)M). Cocaine caused concentration-dependent alteration of response. At 10(-4)M, cocaine attenuated mean maximal norepinephrine-induced vasoconstriction 46.2% (P < 0.05). At 10(-5)M, cocaine increased sensitivity to norepinephrine (log EC50 decreased -6.63 +/- 0.09 to -7.11 +/- 0.03) and to serotonin (log EC50 decreased -7.24 +/- 0.04 to -7.81 +/- 0.09) (P < 0.05). The higher concentration of cocaine (10(-4)M) did not significantly decrease log EC50 norepinephrine. Cocaine (10(-4)M) also attenuated the response to single doses of norepinephrine (10(-6)M) and serotonin (10(-6)M) by 26.5% and 40.0%, respectively (P < or = 0.05). It is concluded that cocaine has concentration-dependent effects on vasoconstriction of the fetal sheep cerebral artery in vitro. This cocaine-induced alteration of cerebral vascular responsiveness to monoamines may be important in the regulation of fetal cerebral blood flow.

  18. Effects of renal artery stenting on renal function and blood pressure in patients with atherosclerotic renovascular disease

    Institute of Scientific and Technical Information of China (English)

    张奇; 沈卫峰; 张瑞岩; 张建盛; 胡健; 张宪

    2003-01-01

    Objective To study the effects of percutaneous renal artery intervention on renal function and blood pressure in patients with renal artery stenosis. Methods Eighty-seven patients with severe uni- or bi-lateral renal artery stenosis (luminal diameter narrowing ≥70%) and clinical hypertension received renal artery stenting between January 2002 and December 2002. The changes in blood pressure and serum creatinine level and creatinine clearance (CCr) 48 hours after intervention and during 6 months of follow-up were assessed.Results Renal stenting was performed in 98 stenotic arteries of 87 patients, and the procedural success rate was 100%. Serum creatinine level was slightly elevated from (176±21) μmol/L to (179±11) μmol/L (P=0.15) 48 hours after the procedure, but significantly decreased to (149±15) μmol/L at 6 months (P<0.001). CCr was also greatly improved [(37±11) ml/min before versus (51±8) ml/min at 6 months, P<0.001]. During follow-up, 61% of the patients experienced a normal renal function. Despite conventional medical treatment, systolic and diastolic blood pressures were also significantly decreased after stenting [(163±23)/(96±13) mm Hg before versus (148±12)/(79±15) mm Hg at 6 months, all P<0.001], and hypertension was well controlled in 67% of the patients at 6 months ' follow-up.Conclusion Renal artery stenting has a high success rate and is effective in improving renal function and blood pressure for patients with severe renal artery stenosis.

  19. Successful treatment of combined vaginal and broad ligament hematoma using pelvic pressure pack and arterial embolization

    Institute of Scientific and Technical Information of China (English)

    Ma Runmei; Lao Terence T; Feng Yukun; Zhao Wei; Huang Jianqiang; Liang GuoHua; Li Hongyu; Chen Zhuo

    2005-01-01

    Objective:To assess using the pelvic pressure pack as temporizing treatment for combined vaginal and broad ligament hematoma before selective arterial embolization could be undertaken.Methods:A 29-year-old woman was transferred because of a 10cm right upper vaginal hematoma found shortly after the spontaneous delivery of a 3400g infant at term.Following evacuation of the clots,the patient's condition deteriorated with the appearance of a painful right pelvic mass,displacing the uterus.At laparotomy,the hematoma extended between the folds of the broad ligament into the pelvic sidewall.After evacuation of the clots,hemostasis failed despite subtotal hysterectomy.Eventually a pressure pack created from joined gauze rolls was used to fill up the pelvic cavity and achieved hemostasis before abdominal closure.When the vaginal pack was removed 30 hours later,vaginal bleeding recurred,and bilateral hypogastric embolization was performed with Gianturco coils.Results:The patient was successfully treated by this way and discharged uneventfully.Conclusion:In combined vaginal and broad ligament hematoma,pelvic pressure pack can be used to ensure maternal survival until definitive treatment with angiographic embolization.

  20. Multichannel Blind Deconvolution of the Arterial Pressure using Ito Calculus Method

    Directory of Open Access Journals (Sweden)

    M. El-Sayed Waheed

    2015-11-01

    Full Text Available Multichannel Blind Deconvolution (MBD is a powerful tool particularly for the identification and estimation of dynamical systems in which a sensor, for measuring the input, is difficult to place. This paper presents Ito calculus method for the estimation of the unknown time-varying coefficient. The arterial network is modelled as a Finite Impulse Response (FIR filter with unknown coefficients. A new tool for estimation of both the central arterial pressure and the unknown channel dynamics has been developed. The convolution process is modelled as a Finite Impulse Response (FIR filter with unknown coefficients. The source signal is also unknown. Assuming that one of the FIR filter coefficients are time varying, we have been able to get accurate estimation results for the source signal, even though the filter order is unknown. The time varying filter coefficients have been estimated through the SC algorithm, and we have been able to deconvolve the measurements and obtain both the source signal and the convolution path. The positive results demonstrate that the SC approach is superior to conventional methods.

  1. Raynaud's phenomenon is correlated with elevated systolic pulmonary arterial pressure in patients with systemic lupus erythematosus.

    Science.gov (United States)

    Kasparian, A; Floros, A; Gialafos, E; Kanakis, M; Tassiopoulos, S; Kafasi, N; Vaiopoulos, G

    2007-01-01

    In patients with Systemic lupus erythematosus (SLE), Raynaud phenomenon (RP) is frequently present and associated with pulmonary hypertension (PHT). Elevated pulmonary artery systolic pressure (PASP) is an indicator of PHT and can be estimated noninvasively. We attempt to explore the significance of RP in SLE and to correlate it with clinical and serological parameters of the disease. The study population consisted of 34 patients (age, sex and disease duration matched) who fulfilled the revised SLE criteria of the American College of Rheumatology, and were categorized into two groups: Group 1 had patients having SLE and RP (2 males/15 females, mean age 45 +/- 18 years) and group 2 had patients with SLE but without RP (3 males/14 females, mean age 40 +/- 14 years. Detailed cardiac ultrasound was performed including measurement of PASP, while clinical and serological features of both groups were collected and correlated. Significant differences were shown in the presence of arterial hypertension (P < 0.05), arthralgias (P < 0.005), arthritis (P < 0.05), myalgias (P < 0.05), alopecia (P < 0.05) and PASP (P < 0.0001). No difference was observed among the cardiac ultrasound indices and the ejection fraction between the two groups. PASP was significantly correlated with RP, while no correlation was observed regarding the disease duration. In patients with SLE, the presence of RP was associated with elevation in PASP. Further investigation is needed to clarify the significance of this relation.

  2. Signal quality quantification and waveform reconstruction of arterial blood pressure recordings.

    Science.gov (United States)

    Fanelli, A; Heldt, T

    2014-01-01

    Arterial blood pressure (ABP) is an important vital sign of the cardiovascular system. As with other physiological signals, its measurement can be corrupted by different sources of noise, interference, and artifact. Here, we present an algorithm for the quantification of signal quality and for the reconstruction of the ABP waveform in noise-corrupted segments of the measurement. The algorithm quantifies the quality of the ABP signal on a beat-by-beat basis by computing the normalized mean of successive differences of the ABP amplitude over each beat. In segments of poor signal quality, the ABP wavelets are then reconstructed on the basis of the expected cycle duration and envelope information derived from neighboring ABP wavelet segments. The algorithm was tested on two datasets of ABP waveform signals containing both invasive radial artery ABP and noninvasive ABP waveforms. Our results show that the approach is efficient in identifying the noisy segments (accuracy, sensitivity and specificity over 95%) and reliable in reconstructing beats that were artificially corrupted.

  3. Wall shear stress and pressure distribution on aneurysms and infundibulae in the posterior communicating artery bifurcation.

    Science.gov (United States)

    Baek, Hyoungsu; Jayaraman, Mahesh V; Karniadakis, George Em

    2009-12-01

    A growing number of cases of rupture at an infundibulum, progression of infundibulum to a frank aneurysm, and subarachnoid hemorrhage (SAH) in the posterior communicating artery (PCoA) have been reported. Using patient-specific geometric models of the supraclinoid internal carotid artery (ICA) with PCoA infundibulum or aneurysm, high-resolution computational fluid dynamics simulations were performed by solving the Navier-Stokes equations with a spectral/hp element method. Simulation results show that the flow impinges at the distal wall of infundibulum near the outside of the ICA bend and creates a region of higher pressure (4-5 mmHg) surrounded by a band of a high wall shear stress (WSS) (20-30 N/m(2) on average). At the proximal end of the infundibulum, another stagnation area is formed characterized by low WSS (shear index. This impingement region seems to coincide with the locations of the rupture of infundibulae or progression to aneurysms. In addition, the pulsatile flow becomes unstable due to the presence of aneurysms or aneurysm-like infundibulae, and this leads to WSS temporal fluctuations inside the aneurysm, which may accelerate the degenerative processes in the vessel walls.

  4. The Correlation between Systolic Blood Pressure Measured by Return to Flow Versus Systolic Blood Pressure Measured by Arterial Catheter in the Adult Anesthetized Patient.

    Science.gov (United States)

    1986-12-01

    a U-tube and mercury manometer for other research, he did not use it to measure arterial blood pressure (30). It was almost a century 34 N N 35 later...use of this mercury manometer decreased the size of the measuring apparatus more than 27 times (30). Carl Ludwig made an important contribution to...direct measurement of blood pressure in 1847 when he added a i graphic recording device to the mercury manometer . This eliminated observer error and

  5. Treatment of hypertension and metabolic syndrome: lowering blood pressure is not enough for organ protection, new approach-arterial destiffening.

    Science.gov (United States)

    Zimlichman, Reuven

    2014-10-01

    Cardiovascular risk factors (CVRFs) have been shown to induce end organ damage. Until now, the main approach to reduce CVRF-induced end organ damage was by normalization of CVRFs; this approach was found effective to reduce damage and cardiovascular (CV) events. However, a residual risk always remained even when CVRFs were optimally balanced. An additional risk factor which has an immense effect on the progression of end organ damage is aging. Aging is accompanied by gradual stiffening of the arteries which finally leads to CV events. Until recently, the process of arterial aging was considered as unmodifiable, but this has changed. Arterial stiffening caused by the aging process is similar to the changes seen as a result of CVRF-induced arterial damage. Actually, the presence of CVRFs causes faster arterial stiffening, and the extent of damage is proportional to the severity of the CVRF, the length of its existence, the patient's genetic factors, etc. Conventional treatments of osteoporosis and of hormonal decline at menopause are potential additional approaches to positively affect progression of arterial stiffening. The new approach to further decrease progression of arteriosclerosis, thus preventing events, is the prevention of age-associated arterial structural changes. This approach should further decrease age-associated arterial stiffening. A totally new promising approach is to study the possibility of affecting collagen, elastin, and other components of connective tissue that participate in the process of arterial stiffening. Reduction of pulse pressure by intervention in arterial stiffening process by novel methods as breaking collagen cross-links or preventing their formation is an example of future directions in treatment. This field is of enormous potential that might be revolutionary in inducing further significant reduction of cardiovascular events.

  6. Autoregulation of cerebral blood flow to changes in arterial pressure in mild Alzheimer's disease.

    Science.gov (United States)

    Zazulia, Allyson R; Videen, Tom O; Morris, John C; Powers, William J

    2010-11-01

    Studies in transgenic mice overexpressing amyloid precursor protein (APP) demonstrate impaired autoregulation of cerebral blood flow (CBF) to changes in arterial pressure and suggest that cerebrovascular dysfunction may be critically important in the development of pathological Alzheimer's disease (AD). Given the relevance of such a finding for guiding hypertension treatment in the elderly, we assessed autoregulation in individuals with AD. Twenty persons aged 75±6 years with very mild or mild symptomatic AD (Clinical Dementia Rating 0.5 or 1.0) underwent (15)O-positron emission tomography (PET) CBF measurements before and after mean arterial pressure (MAP) was lowered from 107±13 to 92±9 mm Hg with intravenous nicardipine; (11)C-PIB-PET imaging and magnetic resonance imaging (MRI) were also obtained. There were no significant differences in mean CBF before and after MAP reduction in the bilateral hemispheres (-0.9±5.2 mL per 100 g per minute, P=0.4, 95% confidence interval (CI)=-3.4 to 1.5), cortical borderzones (-1.9±5.0 mL per 100 g per minute, P=0.10, 95% CI=-4.3 to 0.4), regions of T2W-MRI-defined leukoaraiosis (-0.3±4.4 mL per 100 g per minute, P=0.85, 95% CI=-3.3 to 3.9), or regions of peak (11)C-PIB uptake (-2.5±7.7 mL per 100 g per minute, P=0.30, 95% CI=-7.7 to 2.7). The absence of significant change in CBF with a 10 to 15 mm Hg reduction in MAP within the normal autoregulatory range demonstrates that there is neither a generalized nor local defect of autoregulation in AD.

  7. Skin perfusion pressure measured by isotope washout in legs with arterial occlusive disease. Evaluation of different tracers, comparison to segmental systolic pressure, angiography and transcutaneous oxygen tension and variations during changes in systemic blood pressure

    DEFF Research Database (Denmark)

    Holstein, P; Trap-Jensen, J; Bagger, H

    1983-01-01

    The skin perfusion pressure (SPP) measured as the isotope washout cessation external pressure is valuable in selection of major amputation level. Five methodological investigations important to clinical use were carried out: (1) In five normal legs and 10 legs with arterial occlusive disease (AOD...... in legs with arterial occlusions at two levels or more; (4) In 47 legs with AOD, the SPP on the calf or on the thigh was compared with transcutaneously measured pO2. The two different methods correlated statistically significant, but the scatter was great; (5) During induced variations in systemic blood...... pressure in seven patients (12 legs with AOD), the segmental SPP and the segmental systolic blood pressure were found on average to vary in proportion with intra-arterial mean and systolic pressure respectively; however, this proportional relationship was not valid for the individual leg. It is concluded...

  8. Increased level of glycated hemoglobin portends high risk of coronary artery stenosis

    Institute of Scientific and Technical Information of China (English)

    ZENG FAN-fang; WANG Li-li; LONG Juan; YI Wen-ya; LUO Ying

    2016-01-01

    Background Increased level of glycated hemoglobin (HbA1c) is associated with higher incidence of coronary artery disease (CAD) in the diabetics.However,the relationship between HbAlc and the risk of coronary artery stenosis in the non-diabetics is controversial.Methods A retrospective research was conducted on 338 enrolled participants who have undergone 2 times of coronary angiographic examination within the past year.Clinical and laboratory variables at the initial and the second time of admission were collected.According to the initial median HbA1c level,all participants were divided into two groups named lower and higher groups.The relationship between HbA1c level and the risk of coronary artery stenosis over time was evaluated.Results The initial values of HbA1c in lower and upper groups were 5.78 ± 0.35% and 6.21 ± 0.32% (P < 0.05).As compared to the lower group,the percentages of male and smoking participants,and the serum level of CRP were significantly higher in the higher group (P < 0.05).Other traditional risk factors were comparable between the two groups.There were 54.2% and 55.2% participants with single vessel stenosis,and 45.8% and 44.8% with multiple vessel stenoses,respectively in the two groups without significant difference.The second time of admission,were 308.5± 25.4 days (lower group) and 300.7 ± 30.1 days (higher group) from the initial admission.Although no significant changes of HbA1c level were observed when compared to initial,HbA1c level in the higher group was still significantly higher in comparison to the lower group (6.24 ± 0.39% vs.5.80 ± 0.36%,P =0.008).The percentage of new coronary artery stenosis (≥ 50% stenosis) was higher in the higher group than that in the lower group (41.7% vs.32.3%,P < 0.001).Multivariate regression analyses suggested that HbAlc remained independent factor associated with coronary artery stenoses after extensive adjustment for risk factors.Conclusion In the nondiabetics,increased

  9. Association between long-term air pollution and increased blood pressure and hypertension in China.

    Science.gov (United States)

    Dong, Guang-Hui; Qian, Zhengmin Min; Xaverius, Pamela K; Trevathan, Edwin; Maalouf, Salwa; Parker, Jamaal; Yang, Laiji; Liu, Miao-Miao; Wang, Da; Ren, Wan-Hui; Ma, Wenjun; Wang, Jing; Zelicoff, Alan; Fu, Qiang; Simckes, Maayan

    2013-03-01

    Several studies have investigated the short-term effects of ambient air pollutants in the development of high blood pressure and hypertension. However, little information exists regarding the health effects of long-term exposure. To investigate the association between residential long-term exposure to air pollution and blood pressure and hypertension, we studied 24 845 Chinese adults in 11 districts of 3 northeastern cities from 2009 to 2010. Three-year average concentration of particles with an aerodynamic diameter ≤10 µm (PM(10)), sulfur dioxide (SO(2)), nitrogen dioxides (NO(2)), and ozone (O(3)) were calculated from monitoring stations in the 11 districts. We used generalized additive models and 2-level logistic regressions models to examine the health effects. The results showed that the odds ratio for hypertension increased by 1.12 (95% confidence interval [CI], 1.08-1.16) per 19 μg/m(3) increase in PM(10), 1.11 (95% CI, 1.04-1.18) per 20 μg/m(3) increase in SO(2), and 1.13 (95% CI, 1.06-1.20) per 22 μg/m(3) increase in O(3). The estimated increases in mean systolic and diastolic blood pressure were 0.87 mm Hg (95% CI, 0.48-1.27) and 0.32 mm Hg (95% CI, 0.08-0.56) per 19 μg/m(3) interquartile increase in PM(10), 0.80 mm Hg (95% CI, 0.46-1.14) and 0.31 mm Hg (95% CI, 0.10-0.51) per 20 μg/m(3) interquartile increase in SO(2), and 0.73 mm Hg (95% CI, 0.35-1.11) and 0.37 mm Hg (95% CI, 0.14-0.61) per 22 μg/m(3) interquartile increase in O(3). These associations were only statistically significant in men. In conclusion, long-term exposure to PM(10), SO(2), and O(3) was associated with increased arterial blood pressure and hypertension in the study population.

  10. Elevated pulmonary artery pressure and brain natriuretic peptide in high altitude pulmonary edema susceptible non-mountaineers

    Science.gov (United States)

    Gupta, Rajinder K.; Himashree, G.; Singh, Krishan; Soree, Poonam; Desiraju, Koundinya; Agrawal, Anurag; Ghosh, Dishari; Dass, Deepak; Reddy, Prassana K.; Panjwani, Usha; Singh, Shashi Bala

    2016-01-01

    Exaggerated pulmonary pressor response to hypoxia is a pathgonomic feature observed in high altitude pulmonary edema (HAPE) susceptible mountaineers. It was investigated whether measurement of basal pulmonary artery pressure (Ppa) and brain natriuretic peptide (BNP) could improve identification of HAPE susceptible subjects in a non-mountaineer population. We studied BNP levels, baseline hemodynamics and the response to hypoxia (FIo2 = 0.12 for 30 min duration at sea level) in 11 HAPE resistant (no past history of HAPE, Control) and 11 HAPE susceptible (past history of HAPE, HAPE-S) subjects. Baseline Ppa (19.31 ± 3.63 vs 15.68 ± 2.79 mm Hg, p < 0.05) and plasma BNP levels (52.39 ± 32.9 vs 15.05 ± 9.6 pg/ml, p < 0.05) were high and stroke volume was less (p < 0.05) in HAPE-S subjects compared to control. Acute hypoxia produced an exaggerated increase in heart rate (p < 0.05), mean arterial pressure (p < 0.05) and Ppa (28.2 ± 5.8 vs 19.33 ± 3.74 mm Hg, p < 0.05) and fall in peripheral oxygen saturation (p < 0.05) in HAPE-S compared to control. Receiver operating characteristic (ROC) curves showed that Ppa response to acute hypoxia was the best variable to identify HAPE susceptibility (AUC 0.92) but BNP levels provided comparable information (AUC 0.85). BNP levels are easy to determine and may represent an important marker for the determination of HAPE susceptibility. PMID:26892302

  11. Neural set point for the control of arterial pressure: role of the nucleus tractus solitarius

    Directory of Open Access Journals (Sweden)

    Valentinuzzi Max E

    2010-01-01

    Full Text Available Abstract Background Physiological experiments have shown that the mean arterial blood pressure (MAP can not be regulated after chemo and cardiopulmonary receptor denervation. Neuro-physiological information suggests that the nucleus tractus solitarius (NTS is the only structure that receives information from its rostral neural nuclei and from the cardiovascular receptors and projects to nuclei that regulate the circulatory variables. Methods From a control theory perspective, to answer if the cardiovascular regulation has a set point, we should find out whether in the cardiovascular control there is something equivalent to a comparator evaluating the error signal (between the rostral projections to the NTS and the feedback inputs. The NTS would function as a comparator if: a its lesion suppresses cardiovascular regulation; b the negative feedback loop still responds normally to perturbations (such as mechanical or electrical after cutting the rostral afferent fibers to the NTS; c perturbation of rostral neural structures (RNS to the NTS modifies the set point without changing the dynamics of the elicited response; and d cardiovascular responses to perturbations on neural structures within the negative feedback loop compensate for much faster than perturbations on the NTS rostral structures. Results From the control theory framework, experimental evidence found currently in the literature plus experimental results from our group was put together showing that the above-mentioned conditions (to show that the NTS functions as a comparator are satisfied. Conclusions Physiological experiments suggest that long-term blood pressure is regulated by the nervous system. The NTS functions as a comparator (evaluating the error signal between its RNS and the cardiovascular receptor afferents and projects to nuclei that regulate the circulatory variables. The mean arterial pressure (MAP is regulated by the feedback of chemo and cardiopulmonary receptors and

  12. Nitric Oxide Increases Arterial Endotheial Permeability through Mediating VE-Cadherin Expression during Arteriogenesis

    Science.gov (United States)

    Wu, Xiaoqiong; Guan, Yinglu; Zhang, Bin; Cai, Weijun; Schaper, Jutta; Schaper, Wolfgang

    2015-01-01

    Macrophage invasion is an important event during arteriogenesis, but the underlying mechanism is still only partially understood. The present study tested the hypothesis that nitric oxide (NO) and VE-cadherin, two key mediators for vascular permeability, contribute to this event in a rat ischemic hindlimb model. In addition, the effect of NO on expression of VE-caherin and endothelial permeability was also studied in cultured HUVECs. We found that: 1) in normal arteriolar vessels (NAV), eNOS was moderately expressed in endothelial cells (EC) and iNOS was rarely detected. In contrast, in collateral vessels (CVs) induced by simple femoral artery ligation, both eNOS and iNOS were significantly upregulated (PEBE) was low in the musculus gracilis, FITC-dextron leakage was not detected in the vascular wall and few macrophages were observed in perivascular space. In contrast, EBE was significantly increased in femoral artery ligation rats, FITC-dextron leakage and increased amounts of macrophages were detected in CVs, which were further enhanced by administration of NONOate, but inhibited by L-NAME supplement; 4) in vitro experiments confirmed that an increase in NO production reduced VE-cadherin expression, correlated with increases in the permeability of HUVECs. In conclusion, our data for the first time reveal the expression profile of VE-cadherin and alterations of vascular permeability in CVs, suggesting that NO-mediated VE-cadherin pathway may be one important mechanism responsible, at least in part, for macrophage invasion during arteriogenesis. PMID:26133549

  13. Associations of blood pressure and arterial compliance with occupational noise exposure in female workers of textile mill

    Institute of Scientific and Technical Information of China (English)

    NI Chun-hui; ZHANG Yu-jun; CHEN Zhi-yong; ZHOU Yin; ZHOU Jian-wei; Pan Jing-jing; LIU Nian; WANG Jun; LIANG Chen-ke; ZHANG Zhi-zhong

    2007-01-01

    Background There are few studies on the arterial compliance of noise exposure. The purpose of this study was to understand the relationship between hearing loss, blood pressure and arterial compliance of female workers who exposed to occupational noise in a textile mill.Methods The noise levels in the workplace were measured with a HS6288 sound level meter. Cumulated noise exposure (CNE) was calculated according to the noise intensity and the exposure period. Hearing ability and arterial compliance were measured in 618 noise exposed workers. The database was set up with EpiData and the statistical analysis was performed with SAS software 9.1.3.Results The noise levels were 80.1dB(A) to 113.5dB(A), of which the levels at 92.5% of the noise monitoring sites were over the national standard. The incidence of high frequency hearing loss (HFHL) was 24.43% and language frequency hearing impairment (LFHI) was 0.81%. The incidence of hypertension was 7.93%. Both systolic blood pressure (SBP)and diastolic blood pressure (DBP) in the high frequency hearing loss group were significantly higher than those in the normal hearing group (P<0.05), while C1 (large artery compliance) and C2 (small artery compliance) were significantly lower (P<0.05). The high frequency hearing threshold (HFHT) of the hypertension group was significantly higher than in the normal blood pressure group (P<0.05), while C1 and C2 were significantly lower (P<0.05). C1 and C2 had a negative correlation with HFHT, SBP, DBP, mean of arterial pressure (MAP), pulse pressure (PP) and pulse rate (PR) (P<0.05).The multiple regression analyses showed that blood pressure and PR were the main influencing factors on C1 and C2.LFHT was an influence on C2 and HFHT on C1.Conclusions Textile mill noise pollution is very serious and has an obvious influence on worker's auditory function. The female workers with Iow artery compliance or with high blood pressure might be suffering from hearing loss; those with noise

  14. Increase in vagal activity during hypotensive lower-body negative pressure in humans

    DEFF Research Database (Denmark)

    Sander-Jensen, K; Mehlsen, J; Stadeager, C

    1988-01-01

    Progressive central hypovolemia is characterized by a normotensive, tachycardic stage followed by a reversible, hypotensive stage with slowing of the heart rate (HR). We investigated circulatory changes and arterial hormone concentrations in response to lower-body negative pressure (LBNP) in six ...

  15. [Arterial CO2- and O2 partial pressure at rest and during exertion in pulmonary emphysema].

    Science.gov (United States)

    Scherrer, M; Zeller, C; Bachofen, H

    1977-07-30

    In 83 patients with severe, largely irreversible bronchial obstruction (FEV1/VC less than 40% and FEV1 after orciprenaline inhalation less than 120% of the control value) and radiologie evidence of AD-emphysema, arterial PCO2 and PO2 were measured at rest in supine position and on the bicycle ergometer during a steady-state exercice of 5 min. Alveolar hypoventilation (PCO2 greater than 45 mm Hg) was most often observed in the cases with FEV1 less than 1.01 (in 22 patients [27%] at rest and in 26 patients [31%] during exercise). However, there was no significant correlation of the PCO2 increase with the degree of bronchial obstruction. In all patients there was a marked inhomogeneity of the alveolar ventilation or the alveolar-capillary O2 transfer in relation to alveolar blood perfusion. Indeed, the alveolar-arterial PO2 difference was increased (40 mm Hg at rest and 45 mm Hg during exercise). The additional increase of this gradient during exercise was due to an unequal distribution of alveolar O2 diffusing capacities in connection with the alveolar blood flow (preceding measurements of the N2 gradient between alveolar air and arterial blood revealed a mean fall from 18 at rest to 8 mm Hg during exercise). The observed deterioration of hypoxemia during exercise (without additional hypercapnia) is to a great extent related to the degree of bronchial obstruction measured by simple spirometry. Thus, measurements of PCO2 and PO2 at rest and during exercise appear to be a helpful adjuvant to routine spirometry in the diagnosis of subclinical emphysema.

  16. Egg ovotransferrin‐derived ACE inhibitory peptide IRW increases ACE2 but decreases proinflammatory genes expression in mesenteric artery of spontaneously hypertensive rats

    Science.gov (United States)

    Majumder, Kaustav; Liang, Guanxiang; Chen, Yanhong; Guan, LeLuo; Davidge, Sandra T.

    2015-01-01

    Scope Egg ovotransferrin‐derived angiotensin converting enzyme (ACE) inhibitory peptide IRW was previously shown to reduce blood pressure in spontaneously hypertensive rats through reduced vascular inflammation and increased nitric oxide‐mediated vasorelaxation. The main objective of the present study was to investigate the molecular mechanism of this peptide through transcriptome analysis by RNAseq technique. Methods and results Total RNA was extracted from kidney and mesenteric arteries; the RNAseq libraries (from untreated and IRW‐treated groups) were constructed and subjected to sequence using HiSeq 2000 system (Illumina) system. A total of 12 764 and 13 352 genes were detected in kidney and mesenteric arteries, respectively. The differentially expressed (DE) genes between untreated and IRW‐treated groups were identified and the functional analysis through ingenuity pathway analysis revealed a greater role of DE genes identified from mesenteric arteries than that of kidney in modulating various cardiovascular functions. Subsequent qPCR analysis further confirmed that IRW significantly increased the expression of ACE‐2, ABCB‐1, IRF‐8, and CDH‐1 while significantly decreased the expression ICAM‐1 and VCAM‐1 in mesenteric arteries. Conclusion Our research showed for the first time that ACE inhibitory peptide IRW could contribute to its antihypertensive activity through increased ACE2 and decreased proinflammatory genes expression. PMID:26016560

  17. Increased risk of venous thromboembolism and arterial cardiovascular events in patients with inflammatory bowel disease

    DEFF Research Database (Denmark)

    Kristensen, Søren Lund; Ahlehoff, Ole; Lindhardsen, Jesper;

    2012-01-01

    This focused review describes the current knowledge of the association between inflammatory bowel disease (IBD) and cardiovascular disease. Atherosclerosis is a chronic inflammatory disease, and as well as venous thromboembolism this disease shares inflammatory mechanisms with IBD. Patients...... with IBD have a high risk of venous thromboembolism especially during IBD flare-ups. Their risk of arterial cardiovascular disease may also be increased. The risk of cardiovascular disease in patients with IBD warrants clinical attention, and it is possible that the risk can be modified by applying anti...

  18. Lowering of blood pressure by increasing hematocrit with non nitric oxide scavenging red blood cells.

    Science.gov (United States)

    Salazar Vázquez, Beatriz Y; Cabrales, Pedro; Tsai, Amy G; Johnson, Paul C; Intaglietta, Marcos

    2008-02-01

    Isovolemic exchange transfusion of 40% of the blood volume in awake hamsters was used to replace native red blood cells (RBCs) with RBCs whose hemoglobin (Hb) was oxidized to methemoglobin (MetHb), MetRBCs. The exchange maintained constant blood volume and produced different final hematocrits (Hcts), varying from 48 to 62% Hct. Mean arterial pressure (MAP) did not change after exchange transfusion, in which 40% of the native RBCs were replaced with MetRBCs, without increasing Hct. Increasing Hct with MetRBCs lowered MAP by 12 mm Hg when Hct was increased 12% above baseline. Further increases of Hct with MetRBCs progressively returned MAP to baseline, which occurred at 62% Hct, a 30% increase in Hct from baseline. These observations show a parabolic "U" shaped distribution of MAP against the change in Hct. Cardiac index, cardiac output divided by body weight, increased between 2 and 17% above baseline for the range of Hcts tested. Peripheral vascular resistance (VR) was decreased 18% from baseline when Hct was increased 12% from baseline. VR and MAP were above baseline for increases in Hct higher than 30%. However, vascular hindrance, VR normalized by blood viscosity (which reflects the contribution of vascular geometry), was lower than baseline for all the increases in Hct tested with MetRBC, indicating prevalence of vasodilation. These suggest that acute increases in Hct with MetRBCs increase endothelium shear stress and stimulate the production of vasoactive factors (e.g., nitric oxide [NO]). When MetRBCs were compared with functional RBCs, vasodilation was augmented for MetRBCs probably due to the lower NO scavenging of MetHb. Consequently, MetRBCs increased the viscosity related hypotension range compared with functional RBCs as NO shear stress vasodilation mediated responses are greater.

  19. Effects of sodium and potassium supplementation on blood pressure and arterial stiffness : a fully controlled dietary intervention study

    NARCIS (Netherlands)

    Gijsbers, L.; Dower, J. I.; Mensink, M.; Siebelink, E.; Bakker, S. J. L.; Geleijnse, J. M.

    2015-01-01

    We performed a randomised, placebo-controlled, crossover study to examine the effects of sodium and potassium supplementation on blood pressure (BP) and arterial stiffness in untreated (pre) hypertensive individuals. During the study, subjects were on a fully controlled diet that was relatively low

  20. [Anesthesia management of geriatric patients with arterial pressure-based cardiac output monitoring FloTrac sensor for emergency surgery].

    Science.gov (United States)

    Yamamoto, Shunsuke; Goto, Koji; Yasuda, Norihisa; Kusaka, Junya; Hidaka, Seigo; Miyakawa, Hiroshi; Noguchi, Takayuki

    2009-06-01

    In cases of emergency surgery for geriatric patients, immediate anesthesia induction and careful intraoperative management is necessary without sufficient preoperative information. We report anesthesia management of a 96-year and a 90-year old patients with FloTrac sensor which is an arterial pressure-based cardiac output monitoring device and is able to manage critical patients effectively and safely during anesthesia.

  1. Finger arterial versus intrabrachial pressure and continuous cardiac output during head-up tilt testing in healthy subjects

    NARCIS (Netherlands)

    Jellema, W.T.; Imholz, B.P.M.; Goudoever, J. van; Wesseling, K.H.; Lieshout, J.J. van

    1996-01-01

    1. The aims of this study were to determine the clinical feasibility of continuous, non-invasive Finapres recordings as a replacement for intrabrachial pressure during a 30 min head-up tilt, and the reliability of continuous cardiac output computation by pulse contour analysis from the finger arteri

  2. Early detection and treatment of myocardial ischaemia after operation using continual ambulatory arterial pressure monitoring and ECG ST segment analysis.

    Science.gov (United States)

    Edwards, N D; Troy, G; Yeo, W; Jackson, P; Reilly, C S

    1995-10-01

    We report a case in which the use of continual ambulatory arterial pressure monitoring and ECG ST-segment analysis allowed early detection and treatment of myocardial ischaemia in the postoperative period. We believe that this case illustrates the potential value of ambulatory monitoring in the early postoperative period in high-risk patients.

  3. Urbanization Increases Pathogen Pressure on Feral and Managed Honey Bees.

    Directory of Open Access Journals (Sweden)

    Elsa Youngsteadt

    Full Text Available Given the role of infectious disease in global pollinator decline, there is a need to understand factors that shape pathogen susceptibility and transmission in bees. Here we ask how urbanization affects the immune response and pathogen load of feral and managed colonies of honey bees (Apis mellifera Linnaeus, the predominant economically important pollinator worldwide. Using quantitative real-time PCR, we measured expression of 4 immune genes and relative abundance of 10 honey bee pathogens. We also measured worker survival in a laboratory bioassay. We found that pathogen pressure on honey bees increased with urbanization and management, and the probability of worker survival declined 3-fold along our urbanization gradient. The effect of management on pathogens appears to be mediated by immunity, with feral bees expressing immune genes at nearly twice the levels of managed bees following an immune challenge. The effect of urbanization, however, was not linked with immunity; instead, urbanization may favor viability and transmission of some disease agents. Feral colonies, with lower disease burdens and stronger immune responses, may illuminate ways to improve honey bee management. The previously unexamined effects of urbanization on honey-bee disease are concerning, suggesting that urban areas may favor problematic diseases of pollinators.

  4. Ambulatory instrument for monitoring indirect beat-to-beat blood pressure in superficial temporal artery using volume-compensation method.

    Science.gov (United States)

    Tanaka, S; Yamakoshi, K

    1996-11-01

    A portable instrument, based on a volume-compensation technique, is designed for ambulatory monitoring of indirect beat-to-beat blood pressure (BP) in the superficial temporal artery. The instrument consists of a small disc-type cuff and a portable unit carried by the subject. Several components are integrated in the cuff for applying counter-pressure to the artery, i.e. a reflectance-type photo-plethysmographic sensor for arterial volume detection, a pressure sensor for cuff pressure Pc measurement and a nozzle flapper-type- electro-pneumatic convertor for controlling Pc. The portable unit includes volume servo control circuitry and a microprocessor-based signal-processing and recording unit. This automatically performs all the necessary measurement procedures and stores into a memory IC element the processed systolic, mean and diastolic blood pressure data, together with pulse intervals on a beat-to-beat basis from the servo-controlled Pc (indirectly measured BP waveform). With this instrument, momentary changes in BP during ambulatory situations such as bicycle ergometer exercise and daily activities including motorway driving are successfully recorded. From the results of simultaneous measurement of the subject's posture changes, the effect of posture change on blood pressure, e.g. baroreceptor-cardiac reflex, is also clearly demonstrated.

  5. Evolution from electrophysiologic to hemodynamic monitoring: the story of left atrial and pulmonary artery pressure monitors

    Directory of Open Access Journals (Sweden)

    Deirdre M Mooney

    2015-10-01

    Full Text Available Heart failure (HF is a costly, challenging and highly prevalent medical condition. Hospitalization for acute decompensation is associated with high morbidity and mortality. Despite application of evidence-based medical therapies and technologies, HF remains a formidable challenge for virtually all healthcare systems. Repeat hospitalizations for acute decompensated HF (ADHF can have major financial impact on institutions and resources. Early and accurate identification of impending ADHF is of paramount importance yet there is limited high quality evidence or infrastructure to guide management in the outpatient setting. Historically, ADHF was identified by physical exam findings or invasive hemodynamic monitoring during a hospital admission; however, advances in medical microelectronics and the advent of device-based diagnostics have enabled long-term ambulatory monitoring of HF patients in the outpatient setting. These monitors have evolved from piggybacking on cardiac implantable electrophysiologic devices to standalone implantable hemodynamic monitors that transduce left atrial or pulmonary artery pressures as surrogate measures of left ventricular filling pressure. As technology evolves, devices will likely continue to miniaturize while their capabilities grow. An important, persistent challenge that remains is developing systems to translate the large volumes of real-time data, particularly data trends, into actionable information that leads to appropriate, safe and timely interventions without overwhelming outpatient cardiology and general medical practices. Future directions for implantable hemodynamic monitors beyond their utility in heart failure may include management of other major chronic diseases such as pulmonary hypertension, end stage renal disease and portal hypertension.

  6. Cardiovascular system identification: Simulation study using arterial and central venous pressures.

    Science.gov (United States)

    Karamolegkos, Nikolaos; Vicario, Francesco; Chbat, Nicolas W

    2015-08-01

    The paper presents a study of the identifiability of a lumped model of the cardiovascular system. The significance of this work from the existing literature is in the potential advantage of using both arterial and central venous (CVP) pressures, two signals that are frequently monitored in the critical care unit. The analysis is done on the system's state-space representation via control theory and system identification techniques. Non-parametric state-space identification is preferred over other identification techniques as it optimally assesses the order of a model, which best describes the input-output data, without any prior knowledge about the system. In particular, a recent system identification algorithm, namely Observer Kalman Filter Identification with Deterministic Projection, is used to identify a simplified version of an existing cardiopulmonary model. The outcome of the study highlights the following two facts. In the deterministic (noiseless) case, the theoretical indicators report that the model is fully identifiable, whereas the stochastic case reveals the difficulty in determining the complete system's dynamics. This suggests that even with the use of CVP as an additional pressure signal, the identification of a more detailed (high order) model of the circulatory system remains a challenging task.

  7. Low arterial pressure on admission as a predictor of mortality in operated patients with type A aortic dissection

    Directory of Open Access Journals (Sweden)

    Pavlović Katica

    2011-01-01

    Full Text Available Background/Aim. Hypertension is a known predictor of proximal aortic dissection, but it is not commonly present in these patients on presentation. The associations between ascending aorta with left ventricular hypertrophy, cardiovascular risk factors and coronary atherosclerosis, and outcome of these patients are not fully elucidated. Methods. This retrospective study included 55 consecutive patients with acute type A aortic dissection treated surgically in our institution during the last 2 years. The diagnosis was based on imaging studies. Diameter of ascending aorta was measured with echocardiography. Results. The mean age of the patients was 55.4 ± 12.19 years, and 72.7% were men. A history of arterial hypertension was present in 76.4% of the patients. Maximal ascending aorta diameter was 4.09 ± 0.59 cm, while patients with frank aneurysm accounted for 5.5%. Systolic blood pressure on admission was < 150 mmHg in 58.2% of the patients. Diastolic blood pressure on admission was < 90 mmHg in 54.5% of the patients. Mean arterial pressure on admission was 104.9 ± 24.6 mmHg. No correlations were demonstrated between maximal ascending aorta diameter and diameter of the left ventricular wall, any obtained risk factor and with coronary artery atherosclerosis (p > 0.05. After six months 11 (20% patients died, while intrahospital mortality was 72%. According to logistic regression analysis which included traditional risk factors, echo parameters, coronary artery disease and logistic euro scor, mean arterial blood pressure was the independent predictor of a six-month mortality [RR 0.956; CI (0.918-0.994 ; p = 0.024]. Conclusion. In our population the acute type A aortic dissection occurred rarely in the setting of frank ascending aortic aneurysms > 5.0 cm. The majority of patients had a history of arterial hypertension. A history of arterial hypertension was not associated with maximal ascending aorta diameter. Mean arterial blood pressure was the

  8. Increased shear stress inhibits angiogenesis in veins and not arteries during vascular development.

    Science.gov (United States)

    Chouinard-Pelletier, Guillaume; Jahnsen, Espen D; Jones, Elizabeth A V

    2013-01-01

    Vascular development is believed to occur first by vasculogenesis followed by angiogenesis. Though angiogenesis is the formation of new vessels, we found that vascular density actually decreases during this second stage. The onset of the decrease coincided with the entry of erythroblasts into circulation. We therefore measured the level of shear stress at various developmental stages and found that it was inversely proportional to vascular density. To investigate whether shear stress was inhibitory to angiogenesis, we altered shear stress levels either by preventing erythroblasts from entering circulation ("low" shear stress) or by injection of a starch solution to increase the blood plasma viscosity ("high" shear stress). By time-lapse microscopy, we show that reverse intussusception (merging of two vessels) is inversely proportional to the level of shear stress. We also found that angiogenesis (both sprouting and splitting) was inversely proportional to shear stress levels. These effects were specific to the arterial or venous plexus however, such that the effect on reverse intussusception was present only in the arterial plexus and the effect on sprouting only in the venous plexus. We cultured embryos under altered shear stress in the presence of either DAPT, a Notch inhibitor, or DMH1, an inhibitor of the bone morphogenetic protein (BMP) pathway. DAPT treatment phenocopied the inhibition of erythroblast circulation ("low" shear stress) and the effect of DAPT treatment could be partially rescued by injection of starch. Inhibition of the BMP signaling prevented the reduction in vascular density that was observed when starch was injected to increase shear stress levels.

  9. Increased arterial vascular tone during the night in patients with essential hypertension

    DEFF Research Database (Denmark)

    Scholze, A; Burkert, A; Mardanzai, K;

    2007-01-01

    The time-dependent incidence of cardiovascular events points to an important role of chronobiology for arterial properties. To evaluate arterial properties in patients with essential hypertension, we assessed arterial vascular tone during sleep at night in patients with essential hypertension...

  10. Application of exercise transcutaneous oxygen pressure measurements for detection of proximal lower extremity arterial disease: a case report.

    Science.gov (United States)

    Mahe, Guillaume; Kalra, Manju; Abraham, Pierre; Liedl, David A; Wennberg, Paul W

    2015-06-01

    Proximal claudication is secondary to ischemia caused by peripheral artery disease (PAD), whereas proximal pseudo-claudication is secondary to other disease processes such as hip arthritis, spinal stenosis, neuropathy, and so forth. The differentiation between the two can be challenging. Exercise transcutaneous oxygen pressure measurement (exercise-TcPO2) allows noninvasive detection of flow-reducing lesions in the proximal arteries and tributaries of the lower extremity arterial tree. We present the first case report in the United States using an exercise-TcPO2 algorithm. A 71-year-old diabetic patient with proximal left-sided and right-calf claudication with indeterminate ankle-brachial indices underwent an exercise-TcPO2 study before and after endovascular intervention. Four TcPO2 probes were placed: one at chest level (reference probe), one on each buttock, and one on the symptomatic calf. The Delta from Resting Oxygen Pressure (DROP) index was calculated at each probe site using a previously validated protocol. Proximal left- and right-calf ischemia were confirmed by the initial exercise-TcPO2, and, after endovascular treatment of the left iliac artery lesion, improvements in proximal exercise-TcPO2 values were found. These data suggest that exercise-TcPO2 can be useful in PAD evaluation in patients with non-compressible arteries and/or proximal claudication.

  11. Blood Pressure Control in Smokers with Arterial Hypertension Who Switched to Electronic Cigarettes

    Directory of Open Access Journals (Sweden)

    Riccardo Polosa

    2016-11-01

    Full Text Available Electronic cigarettes (ECs are battery-operated devices designed to vaporise nicotine, which may help smokers with quitting or reducing their tobacco consumption. No data is available regarding the health effects of ECs use among smokers with arterial hypertension and whether regular use results in blood pressure (BP changes. We investigated long-term changes in resting BP and level of BP control in hypertensive smokers who quit or reduced substantially their tobacco consumption by switching to ECs. A medical records review of patients with hypertension was conducted to identify patients reporting regular daily use of ECs on at least two consecutive follow-up visits. Regularly smoking hypertensive patients were included as a reference group. A marked reduction in cigarette consumption was observed in ECs users (n = 43 though consumption remained unchanged in the control group (n = 46. Compared to baseline, at 12 months (follow-up visit 2 decline in cigarette consumption was associated with significant reductions in median (25th-, 75th-centile systolic BP (140 (134.5, 144 to 130 (123.5, 138.5 mmHg; p < 0.001 and diastolic BP (86 (78, 90 to 80 (74.5, 90 mmHg; p = 0.006. No significant changes were observed in the control group. As expected, decline in cigarette consumption in the ECs users was also associated with improved BP control. The study concludes that regular ECs use may aid smokers with arterial hypertension reduce or abstain from cigarette smoking, with only trivial post-cessation weight gain. This resulted in improvements in systolic and diastolic BP as well as better BP control.

  12. Blood Pressure Control in Smokers with Arterial Hypertension Who Switched to Electronic Cigarettes

    Science.gov (United States)

    Polosa, Riccardo; Morjaria, Jaymin B.; Caponnetto, Pasquale; Battaglia, Eliana; Russo, Cristina; Ciampi, Claudio; Adams, George; Bruno, Cosimo M.

    2016-01-01

    Electronic cigarettes (ECs) are battery-operated devices designed to vaporise nicotine, which may help smokers with quitting or reducing their tobacco consumption. No data is available regarding the health effects of ECs use among smokers with arterial hypertension and whether regular use results in blood pressure (BP) changes. We investigated long-term changes in resting BP and level of BP control in hypertensive smokers who quit or reduced substantially their tobacco consumption by switching to ECs. A medical records review of patients with hypertension was conducted to identify patients reporting regular daily use of ECs on at least two consecutive follow-up visits. Regularly smoking hypertensive patients were included as a reference group. A marked reduction in cigarette consumption was observed in ECs users (n = 43) though consumption remained unchanged in the control group (n = 46). Compared to baseline, at 12 months (follow-up visit 2) decline in cigarette consumption was associated with significant reductions in median (25th-, 75th-centile) systolic BP (140 (134.5, 144) to 130 (123.5, 138.5) mmHg; p < 0.001) and diastolic BP (86 (78, 90) to 80 (74.5, 90) mmHg; p = 0.006). No significant changes were observed in the control group. As expected, decline in cigarette consumption in the ECs users was also associated with improved BP control. The study concludes that regular ECs use may aid smokers with arterial hypertension reduce or abstain from cigarette smoking, with only trivial post-cessation weight gain. This resulted in improvements in systolic and diastolic BP as well as better BP control. PMID:27845734

  13. School burnout: increased sympathetic vasomotor tone and attenuated ambulatory diurnal blood pressure variability in young adult women.

    Science.gov (United States)

    May, Ross W; Sanchez-Gonzalez, Marcos A; Fincham, Frank D

    2015-01-01

    Two studies examined autonomic and cardiovascular functioning that may link school burnout to cardiovascular risk factors in young healthy adult females. Study 1 (N = 136) investigated whether school burnout was related to resting values of blood pressure (BP) and blood pressure variability (BPV) through laboratory beat-to-beat BP assessment. Study 2 (N = 94) examined the link between school burnout and diurnal BPV through ambulatory BP monitoring. Controlling for anxiety and depressive symptomatology, school burnout demonstrated strong positive relationships with indices of cardiac sympathovagal tone, sympathetic vasomotor tone, inefficient myocardial oxygen consumption, increased 24-h ambulatory heart rate and BP, blunted BP diurnal variability, and increased arterial stiffness. These studies establish cardiovascular biomarkers of school burnout and suggest that even in a seemingly healthy sample school burnout may predispose females to increased cardiovascular risk. Several future lines of research are outlined.

  14. Circulating ghrelin was negatively correlated with pulmonary arterial pressure in atrial septal defect patients

    Institute of Scientific and Technical Information of China (English)

    LI Zhao-feng; ZHOU Da-xin; PAN Wen-zhi; ZHANG Lei; GE Jun-bo

    2013-01-01

    Background Ghrelin was found to attenuate the magnitude of pulmonary arterial hypertension and pulmonary vascular remodeling in rats.The objective of this study was to explore the fasting plasma ghrelin level and the relationships between ghrelin and pulmonary arterial pressure (PAP) in atrial septal defect (ASD) patients with pulmonary arterial hypertension (PAH).Methods Fasting plasma ghrelin,obestatin,and insulin levels were measured by enzyme linked immunosorbent assay (ELISA) method in ASD patients with or without PAH according to the manufacturer's instructions.Insulin resistance was calculated by the homeostasis model of assessment for insulin resistance (HOMA-IR) approach,calculated as fasting insulin (microunits/ml)× fasting blood glucose (mmol/L)/22.5.Comparisons between the parameters of patients with PAH and those of patients with normal PAP were performed with an unpaired Student's t test.The relationships between ghrelin and various clinical parameters were examined by bivariate correlations and multiple regression analysis.Results We found that the fasting plasma ghrelin level and the ratio of ghrelin to obestatin were significantly lower in the PAH group compared with the control group ((582.4±12.8) pg/ml vs.(1045.2±95.5) pg/ml,P <0.05 and 30.5±4.9 vs.70.0±9.7,P <0.01).The fasting plasma obestatin level was higher in the PAH group compared with the control group,but the difference between them was not significant ((23.2±3.1) pg/ml vs.(16.3±1.6) pg/ml,P >0.05).In a multiple regression model analysis,only mean PAP was an independent predictor of ghrelin and the ratio of ghrelin to obestatin (standardized coefficient=0.737,P <0.001 and standardized coefficient=-0.588,P=0.006,respectively).Conclusion Ghrelin is negatively correlated with mean PAP and this suggests that circulating ghrelin might predict the severity of pulmonary hypertension in ASD patients with PAH.

  15. Noninvasive assessment of cardiac output from arterial pressure profiles during exercise.

    Science.gov (United States)

    Antonutto, G; Girardis, M; Tuniz, D; di Prampero, P E

    1995-01-01

    The stroke volume of the left ventricle (SV) was assessed in nine young men (mean age 22.2, ranging from 20 to 25 years) during cycle ergometer upright exercise at exercise intensities from 60 to 150 W (about 20% to 80% of individual maximal aerobic power). The SV was calculated from noninvasive tracings of the arterial blood pressure, determined from photoplethysmograph records and compared to the SV determined simultaneously by pulsed Doppler echocardiography (PDE). Given the relationship SV = As.Z-1 in which A(s) is the area underneath the systolic pressure profile (in millimetres of mercury and second), and Z (in millimetres of mercury and second per millilitre) is the apparent hydraulic impedance of the circulatory system, a prerequisite for the assessment of SV from the photoplethysmograph tracings is a knowledge of Z. The experimental value of Z (hereafter defined Z*) was calculated by dividing A(s) (from the finger photoplethysmograph) by SV as obtained by PDE. When the whole group of subjects was considered, Z* was not greatly affected by the exercise intensity: it amounted to 0.089 (SD 0.028; n = 36). The Z was also estimated independently of any parameter other than heart rate (HR), mean (MAP) and pulse (PP) arterial blood pressure obtained from the photoplethysmograph. A computerized statistical method allowed us to interpolate the experimental values of Z*, HR, PP and MAP by the equation Zm = a.(b + c.HR + d.PP + e.MAP)-1, thus obtaining the coefficients a to e. The mean percentage error between Zm (calculated from the coefficients obtained and Z* was 21.8 (SD 14.3)%. However, it was observed that, in a given subject, Z* was significantly affected by the exercise intensity. Therefore, to improve the estimate of Z a second algorithm was developed to update the experimental value of Z determined initially at rest (Zin). This updated value (Zcor) of Z was calculated as Zcor = Zin. [(f/(i + g.(HR/HRin) + h.(PP/PPin) + 1.(MAP/MAPin)], where HRin, PPin

  16. Increased arterial distensibility and renovascular hypertension in Goldenhar syndrome Aumento de distensibilidade arterial e hipertensão renovascular na Sindrome de Goldenhar

    Directory of Open Access Journals (Sweden)

    Luciano F. Drager

    2005-04-01

    Full Text Available This is a report of the successful angioplastic treatment of an association of renovascular hypertension with renal artery stenosis and the Goldenhar syndrome (a variant of oculoauriculovertebral dysplasia. For the first time to date, this association, which occurred in a 13-year-old girl, is reported. Additionally, increased arterial distensibility in spite of arterial hypertension was detected by noninvasive methods. The similarity of this finding and in those for other genetic diseases, suggests that the vascular lesions could be linked to the Goldenhar syndrome.Relatamos a associação de hipertensão renovascular por estenose de artéria renal e a Sindrome de Goldenhar (variante da displasia oculoauriculovertebral em uma paciente do sexo feminino de 13 anos de idade. Este é o primeiro relato de tratamento por angioplastia. Além disso, detectamos por métodos não invasivos um aumento da distensibilidade arterial, a despeito da hipertensão arterial. A similaridade destes achados com outras doenças genéticas sugere que as alterações vasculares presentes podem estar relacionadas à Síndrome de Goldenhar.

  17. A method for the quantification of the pressure dependent 3D collagen configuration in the arterial adventitia.

    Science.gov (United States)

    Schrauwen, J T C; Vilanova, A; Rezakhaniha, R; Stergiopulos, N; van de Vosse, F N; Bovendeerd, P H M

    2012-11-01

    Collagen plays an important role in the response of the arterial wall to mechanical loading and presumably has a load-bearing function preventing overdistension. Collagen configuration is important for understanding this role, in particular in mathematical models of arterial wall mechanics. In this study a new method is presented to image and quantify this configuration. Collagen in the arterial adventitia is stained with CNA35, and imaged in situ at high resolution with confocal microscopy at luminal pressures from 0 to 140mm Hg. The images are processed with a new automatic approach, utilizing techniques intended for MRI-DTI data. Collagen configuration is quantified through three parameters: the waviness, the transmural angle and the helical angle. The method is demonstrated for the case of carotid arteries of the white New Zealand rabbit. The waviness indicated a gradual straightening between 40 and 80mm Hg. The transmural angle was about zero indicating that the fibers stayed within an axial-circumferential plane at all pressures. The helical angle was characterized by a symmetrical distribution around the axial direction, indicating a double symmetrical helix. The method is the first to combine high resolution imaging with a new automatic image processing approach to quantify the 3D configuration of collagen in the adventitia as a function of pressure.

  18. Trabeculectomy for traumatic hyphema with increased intraocular pressure.

    Science.gov (United States)

    Graul, T A; Ruttum, M S; Lloyd, M A; Radius, R L; Hyndiuk, R A

    1994-02-15

    We reviewed the medical records of 11 consecutive patients who underwent trabeculectomy with anterior chamber washout and peripheral iridectomy as the primary surgical treatment for traumatic hyphema that was unresponsive to medical management. The mean intraocular pressure before surgery was 48 mm Hg. In ten of the patients the intraocular pressure was lowered to 21 mm Hg or lower after surgery and remained below that level up to the most recent follow-up visit, which ranged from eight to 97 months. One patient required a topical beta-blocker and oral acetazolamide to lower pressure to this level after surgery. Eight patients had visual acuity of 20/60 or better at last follow-up. Corneal blood staining occurred in eight patients. Compared with other techniques for surgical management of traumatic hyphema, trabeculectomy provides a means to keep intraocular pressure lowered while the remaining blood is clearing from the anterior chamber. Trabeculectomy with anterior chamber washout and peripheral iridectomy appears to be a safe and reliable procedure in the management of traumatic hyphemas in which medical management fails to control intraocular pressure.

  19. Increased activity of chondroitin sulfate-synthesizing enzymes during proliferation of arterial smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Hollmann, J.; Thiel, J.; Schmidt, A.; Buddecke, E.

    1986-12-01

    Cultured arterial smooth muscle cells incorporate (/sup 35/S)sulfate into the extracellular chondroitin sulfate/dermatan sulfate containing proteoglycans at a higher rate in the phase of logarithmic growth than do non-dividing cells. The cell growth-dependent decrease in /sup 35/S incorporation with increasing cell density is accompanied by a decrease in the activity of chondroitin sulfate-synthesizing enzymes. The specific activity of xylosyl transferase, N-acetylgalactosaminyl transferase I and chondroitin sulfotransferase declines as the cells proceed from low to high densities. The corresponding correlation coefficients are 0.86, 0.91 and 0.89. The ratio of C-60H/C-40H sulfation of chondroitin shows a cell proliferation-dependent decrease indicating an inverse correlation of chondroitin 6-sulfotransferase and chondroitin 4-sulfotransferase activity. The observed changes in the expression of enzyme activities are thought to have some implications in the pathogenesis of arteriosclerosis, the initial stages of which are characterized by proliferation of arterial smooth muscle cells.

  20. Preventive and therapeutic effects of penehyclidine hydrochloride on morphine-induced increased bladder pressure, urinary bladder sphincter pressure and histological damage in rabbits

    Institute of Scientific and Technical Information of China (English)

    SHI Wei-dong; WANG Wei-wei; CUI Xiao-guang; PAN Peng; ZHANG Bing; LI Wen-zhi

    2012-01-01

    Background Morphine has become the preferred drug for analgesia.However,analgesic doses of morphine can result in urinary retention,which is an intractable problem in clinical practice.Though bladder catheterization is one available therapeutic option,data supporting the technique's effectiveness are controversial.As a novel anti-cholinergic medicine developed in China,penehyclidine hydrochloride (PHC) exhibits greater selectivity for M3/M1 receptors than M2 receptors.Therefore,this study aimed to determine the efficacy of PHC in treating urinary retention.Methods Thirty-two healthy male New Zealand white rabbits were randomly divided in four groups (n=8 each) as follows:control group (C group),PHC low-dose group (PL group,0.01 mg/kg of PHC intramuscularly),PHC middle-dose group (PM group,0.02 mg/kg of PHC intramuscularly),and PHC high-dose group (PH group,0.05 mg/kg of PHC intramuscularly).All rabbits were injected intravenously with morphine (1 mg/kg) to induce urinary retention and different doses of PHC were injected intramuscularly in the PL,PM and PH groups.In the C group,1 ml saline was administered instead of PHC.The bladder pressure and the bladder sphincter pressure were recorded at different time points.The plasma concentration of PHC was measured at different time points with high performance liquid chromatography.Arterial blood pressure and heart rate (HR) were recorded at different time points.Results Bladder pressure and urinary bladder sphincter pressure rose significantly from 30 minutes after morphine administration until the end of the experiment.PHC markedly attenuated the elevations in pressure induced by morphine.Morphometric analysis also revealed histological damage,erythrocytes and ruptures of the microcirculation in regions of the submucosa and smooth muscle.Morphometric damage was ameliorated with PHC but not with saline.Hemodynamic data (mean arterial pressure (MAP) and HR) did not differ between groups over the observation period

  1. Pulmonary arterial hypertension : an update

    NARCIS (Netherlands)

    Hoendermis, E. S.

    2011-01-01

    Pulmonary arterial hypertension (PAH), defined as group 1 of the World Heart Organisation (WHO) classification of pulmonary hypertension, is an uncommon disorder of the pulmonary vascular system. It is characterised by an increased pulmonary artery pressure, increased pulmonary vascular resistance a

  2. Multiple level arterial occlusions of the leg. Reliability of indirect thigh pressures in the assessment of proximal arterial obstruction

    DEFF Research Database (Denmark)

    Noer, Ivan; Tønnesen, K H; Lassen, N A

    1981-01-01

    placed as proximally as possible on the thigh. The proximal pressures measured by the two techniques were found to correlate well. Thus, the atraumatic cuff pressure technique is validated which can be of use in evaluating multilevel occlusions and the associated run off problem involved in partial...

  3. Association between poor glycemic control, impaired sleep quality, and increased arterial thickening in type 2 diabetic patients.

    Directory of Open Access Journals (Sweden)

    Koichiro Yoda

    Full Text Available Poor sleep quality is an independent predictor of cardiovascular events. However, little is known about the association between glycemic control and objective sleep architecture and its influence on arteriosclerosis in patients with type-2 diabetes mellitus (DM. The present study examined the association of objective sleep architecture with both glycemic control and arteriosclerosis in type-2 DM patients.Cross-sectional study in vascular laboratory.The subjects were 63 type-2 DM inpatients (M/F, 32/31; age, 57.5±13.1 without taking any sleeping promoting drug and chronic kidney disease. We examined objective sleep architecture by single-channel electroencephalography and arteriosclerosis by carotid-artery intima-media thickness (CA-IMT.HbA1c was associated significantly in a negative manner with REM sleep latency (interval between sleep-onset and the first REM period (β=-0.280, p=0.033, but not with other measurements of sleep quality. REM sleep latency associated significantly in a positive manner with log delta power (the marker of deep sleep during that period (β=0.544, p=0.001. In the model including variables univariately correlated with CA-IMT (REM sleep latency, age, DM duration, systolic blood pressure, and HbA1c as independent variables, REM sleep latency (β=-0.232, p=0.038, but not HbA1c were significantly associated with CA-IMT. When log delta power was included in place of REM sleep latency, log delta power (β=-0.257, p=0.023 emerged as a significant factor associated with CA-IMT.In type-2 DM patients, poor glycemic control was independently associated with poor quality of sleep as represented by decrease of REM sleep latency which might be responsible for increased CA-IMT, a relevant marker for arterial wall thickening.

  4. Portal venous arterialization resulting in increased portal inflow and portal vein wall thickness in rats

    Institute of Scientific and Technical Information of China (English)

    Wen-Gang Li; Yong-Liang Chen; Jing-Xi Chen; Lei Qu; Bin-Dang Xue; Zhi-Hai Peng; Zhi-Qiang Huang

    2008-01-01

    AIM:To explore the influence of portal vein hemodynamic changes after portal venous arterialization(PVA) on peribiliary vascular plexus (PVP)morphological structure and hepatic pathology,and to establish a theoretical basis for the clinical application of PVA.METHODS:Sprague-Dawley rats were randomly divided into control and PVA groups.After PVA,hemodynamic changes of the portal vein and morphological structure of hepatohilar PVP were observed using Doppler ultrasound,liver function tests,ink perfusion transparency management and three-dimensional reconstruction of computer microvisualization,and pathological examination was performed on tissue from the bile duct wall and the liver.RESULTS:After PVA,the cross-sectional area and blood flow of the portal vein were increased,and the increase became more significant over time,in a certain range.If the measure to limit the flow in PVA was not adopted,the high blood flow would lead to dilatation of intrahepatic portal vein and its branches,increase in collagen and fiber degeneration in tunica intima.Except glutamic pyruvic transaminase (GPT),other liver function tests were normal.CONCLUSION:Blood with a certain flow and oxygen content is important for filling the PVP and meeting the oxygen requirement of the bile duct wall.After PVA,It is the anatomic basis to maintain normal morphology of hepatohilar bile duct wall that the blood with high oxygen content and high flow in arterialized portal vein may fill PVP by collateral vessel reflux.A adequate measure to limit blood flow is necessary in PVA.

  5. Hypoxia increases pulmonary arterial thromboxane receptor internalization independent of receptor sensitization.

    Science.gov (United States)

    Fediuk, J; Sikarwar, A S; Lizotte, P P; Hinton, M; Nolette, N; Dakshinamurti, S

    2015-02-01

    Persistent Pulmonary Hypertension of the Newborn (PPHN) is characterized by sustained vasospasm and an increased thromboxane:prostacyclin ratio. Thromboxane (TP) receptors signal via Gαq to mobilize IP3 and Ca(2+), causing pulmonary arterial constriction. We have previously reported increased TP internalization in hypoxic pulmonary arterial (PA) myocytes. Serum-deprived PA myocytes were grown in normoxia (NM) or hypoxia (HM) for 72 h. TP localization was visualized in agonist-naïve and -challenged NM and HM by immunocytochemistry. Pathways for agonist-induced TP receptor internalization were determined by inhibiting caveolin- or clathrin-mediated endocytosis, and caveolar fractionation. Roles of actin and tubulin in TP receptor internalization were assessed using inhibitors of tubulin, actin-stabilizing or -destabilizing agents. PKA, PKC or GRK activation and inhibition were used to determine the kinase responsible for post-agonist receptor internalization. Agonist-naïve HM had decreased cell surface TP, and greater TP internalization after agonist challenge. TP protein did not sort with caveolin-rich fractions. Inhibition of clathrin prevented TP internalization. Both actin-stabilizing and -destabilizing agents prevented TP endocytosis in NM, while normalizing TP internalization in HM. Velocity of TP internalization was unaffected by PKA activity, but PKC activation normalized TP receptor internalization in HM. GRK inhibition had no effect. We conclude that in hypoxic myocytes, TP is internalized faster and to a greater extent than in normoxic controls. Internalization of the agonist-challenged TP requires clathrin, dynamic actin and is sensitive to PKC activity. TP receptor trafficking and signaling in hypoxia are pivotal to understanding increased vasoconstrictor sensitivity.

  6. Arterial line pressure control enhanced extracorporeal blood flow prescription in hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Rosales Laura

    2008-11-01

    Full Text Available Abstract Background In hemodialysis, extracorporeal blood flow (Qb recommendation is 300–500 mL/min. To achieve the best Qb, we based our prescription on dynamic arterial line pressure (DALP. Methods This prospective study included 72 patients with catheter Group 1 (G1, 1877 treatments and 35 arterio-venous (AV fistulae Group 2 (G2, 1868 treatments. The dialysis staff was trained to prescribe Qb sufficient to obtain DALP between -200 to -250 mmHg. We measured ionic clearance (IK: mL/min, access recirculation, DALP (mmHg and Qb (mL/min. Six prescription zones were identified: from an optimal A zone (Qb > 400, DALP -200 to -250 to zones with lower Qb E (Qb -199. Results Treatments distribution in A was 695 (37% in G1 vs. 704 (37.7% in G2 (P = 0.7. In B 150 (8% in G1 vs. 458 (24.5% in G2 (P P = 0.62. IK in A was 214 ± 34 (G1 vs. 213 ± 35 (G2 (P = 0.65. IK Anova between G2 zones was: A vs. C and D (P P = 0.02. Conclusion In conclusion, an optimal Qb can de prescribed with DALP of -200 mmHg. Staff adherence to DLAP treatment prescription could be reached up to 81.3% in catheters and 84.1% in AV fistulae.

  7. Effect of ivabradine on central aortic blood pressure in patients with stable coronary artery disease: What do we know?

    Science.gov (United States)

    Lopatin, Yuri M; Vitale, Cristiana

    2016-12-01

    Treatment of hypertensive patients with beta-blockers decreases central blood pressure (CBP) less than other antihypertensive drugs, which is believed to account for their lesser cardiovascular protection in this setting. Some authors have suggested that decreasing heart rate (HR) with beta-blockers would increase CBP. In contrast to beta-blockers, the anti-anginal agent ivabradine reduces HR without other hemodynamic effects, and represents an attractive tool for exploring the direct relationship between HR and CBP. Here, we review the available clinical data assessing the effect of selective HR reduction with ivabradine on CBP in patients with stable coronary artery disease (CAD). We collected data from five studies which report either increase, decrease, or neutral effects of ivabradine on CBP. Further studies are needed to clarify the exact role of ivabradine on CBP. However, as supported by its pharmacodynamic effect in patients with stable CAD, available evidence to date suggests that ivabradine does not negatively impact CBP when associated with beta-blocker. HR reduction with both beta-blockers and ivabradine remains well-established treatments for the symptomatic treatment of angina patients.

  8. The Effect of High Dose Cholecalciferol on Arterial Stiffness and Peripheral and Central Blood Pressure in Healthy Humans

    DEFF Research Database (Denmark)

    Bressendorff, Iain; Brandi, Lisbet; Schou, Morten

    2016-01-01

    and blood pressure in healthy normotensive adults. METHODS: 40 healthy adults were randomised in this double-blinded study to either oral cholecalciferol 3000 IU/day or matching placebo and were followed for 16 weeks to examine any effects on pulse wave velocity (PWV), augmentation index (AIx), peripheral...... and central blood pressure and 24-hour ambulatory blood pressure. RESULTS: 22 subjects in the cholecalciferol arm and 18 subjects in the placebo arm completed the 16 weeks of follow-up. There was no difference in changes in PWV, AIx corrected for heart rate or central or peripheral blood pressure between...... the two groups. There was no correlation between serum 25-hydroxy vitamin D and any of these parameters. CONCLUSIONS: Oral cholecalciferol 3000 IU/day does not affect arterial stiffness or blood pressure after 16 weeks of treatment in healthy normotensive adults. TRIAL REGISTRATION: ClinicalTrials.gov NCT...

  9. Tricuspid Regurgitation Improvement in Relation to the Amount of Pulmonary Artery Pressure Reduction

    Directory of Open Access Journals (Sweden)

    Mahmood Sheikhfathollahi

    2010-08-01

    Full Text Available Background: Given the common concomitance of tricuspid regurgitation (TR with significant mitral stenosis, we aimed at exploring the relation between TR severity and pulmonary artery hypertension (PAH in patients who underwent mitral balloon valvotomy (MBV.Methods: We analyzed the echocardiography data of 133 consecutive patients (82.0% female, mean age 44.68 ± 12.56 years with different degrees of TR severity that underwent MBV between April 2006 and March 2008. The pulmonary artery systolic pressure (PAPs > 35 mmHg was considered as PAH.Results: Before MBV, 36.20% of the patients had moderate to severe TR, 92.5% PAH, and 18.0% right ventricular (RVdilation (RV dimension ≥ 33 mm. After MBV, TR severity improved in 41.4%, worsened in 8.3%, and did not change in 50.4%. Before and after MBV, PAPs was significantly correlated with TR severity, and the mean PAPs change in patients with improved TR was significantly more than that of patients without TR improvement (p value = 0.042. Tricuspid regurgitation severity and mean PAPs (from 52.83 ± 18.82 to 35.89 ± 9.39 mmHg decreased significantly after MBV (both p values <0.001; this reduction was significantly correlated to the amount of PAPs decrease. A cut-off point of ≥ 19 mmHg reductionin PAPs had a specificity of 71.79% and sensitivity of 52.73% to show TR severity improvement (by Receiver-Operative-Characteristics analysis. The mean of RV dimension decreased from 28.94 ± 5.43 to 27.95 ± 4.67 mm (p value < 0.001. In contrast to patients with RV dilation, TR reduced significantly in patients without RV dilation (p value < 0.001.Conclusion: Improvement in TR severity was directly correlated with the amount of PAPs reduction after MBV. Morestudies are needed to better define a cut-off value for PAPs reduction related to TR severity improvement.

  10. Outflow boundary conditions for 3D simulations of non-periodic blood flow and pressure fields in deformable arteries

    CERN Document Server

    Vignon-Clementel, Irene; Jansen, K E; Taylor, C A; 10.1080/10255840903413565

    2010-01-01

    The simulation of blood flow and pressure in arteries requires outflow boundary conditions that incorporate models of downstream domains. We previously described a coupled multidomain method to couple analytical models of the downstream domains with 3D numerical models of the upstream vasculature. This prior work either included pure resistance boundary conditions or impedance boundary conditions based on assumed periodicity of the solution. However, flow and pressure in arteries are not necessarily periodic in time due to heart rate variability, respiration, complex transitional flow or acute physiological changes. We present herein an approach for prescribing lumped parameter outflow boundary conditions that accommodate transient phenomena. We have applied this method to compute haemodynamic quantities in different physiologically relevant cardiovascular models, including patient-specific examples, to study non-periodic flow phenomena often observed in normal subjects and in patients with acquired or congen...

  11. A prospective study of glomerular filtration rate and arterial blood pressure in insulin-dependent diabetics with diabetic nephropathy

    DEFF Research Database (Denmark)

    Parving, H H; Smidt, U M; Friisberg, B

    1981-01-01

    nephropathy. Twelve of the 14 patients had normal serum creatinine levels. None of the patients received antihypertensive treatment. During the mean observation period of 26 months (range 23 to 33 months) GFR decreased from 107 to 87 ml/min/1.73 m2 (p less than 0.001), serum creatinine remained unchanged: 107...... in arterial blood pressure to a hypertensive level is an early feature of diabetic nephropathy in young insulin-dependent diabetics.......Glomerular filtration rate (GFR, single bolus 51Cr-EDTA technique), serum creatinine, proteinuria and arterial blood pressure have been measured prospectively in 14 young onset insulin-dependent diabetics selected by of persistent proteinuria (greater than 0.5 g/day) secondary to diabetic...

  12. Rationale and methodology of monitoring ambulatory blood pressure and arterial compliance in the Hypertension in the Very Elderly Trial

    OpenAIRE

    2006-01-01

    OBJECTIVE: This article describes the rationale and methodology for the monitoring of ambulatory blood pressure and arterial compliance in hypertensive patients aged 80 years and above. This is a side project of the Hypertension in the Very Elderly Trial. METHODS: The hypertension in the Very Elderly Trial is a multicentre, double-blind, randomized, placebo-controlled trial aiming to investigate the effect of active treatment on cardiovascular and other outcomes in hypertensive patients aged ...

  13. Low-dose plasmid DNA treatment increases plasma vasopressin and regulates blood pressure in experimental endotoxemia

    Directory of Open Access Journals (Sweden)

    Malardo Thiago

    2012-11-01

    Full Text Available Abstract Background Although plasmid DNA encoding an antigen from pathogens or tumor cells has been widely studied as vaccine, the use of plasmid vector (without insert as therapeutic agent requires further investigation. Results Here, we showed that plasmid DNA (pcDNA3 at low doses inhibits the production of IL-6 and TNF-α by lipopolysaccharide (LPS-stimulated macrophage cell line J774. These findings led us to evaluate whether plasmid DNA could act as an anti-inflammatory agent in a Wistar rat endotoxemia model. Rats injected simultaneously with 1.5 mg/kg of LPS and 10 or 20 μg of plasmid DNA had a remarkable attenuation of mean arterial blood pressure (MAP drop at 2 hours after treatment when compared with rats injected with LPS only. The beneficial effect of the plasmid DNA on MAP was associated with decreased expression of IL-6 in liver and increased concentration of plasma vasopressin (AVP, a known vasoconstrictor that has been investigated in hemorrhagic shock management. No difference was observed in relation to nitric oxide (NO production. Conclusion Our results demonstrate for the first time that plasmid DNA vector at low doses presents anti-inflammatory property and constitutes a novel approach with therapeutic potential in inflammatory diseases.

  14. Beneficial effects of prolonged blood pressure control after carotid artery stenting

    Directory of Open Access Journals (Sweden)

    Chang A

    2017-01-01

    Full Text Available Anna Chang,1 Huei-Fong Hung,2 Fang-I Hsieh,3 Wei-Hung Chen,1,4 Hsu-Ling Yeh,1,5 Jiann-Horng Yeh,1,6 Hou-Chang Chiu,1,6 Li-Ming Lien1,4 1Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, 2Department of Cardiology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, 3School of Public Health, College of Public Health, Taipei Medical University, Taipei, 4School of Medicine, College of Medicine, Taipei Medical University, Taipei, 5Institute of Public Health, National Yang-Ming University, Taipei, 6School of Medicine, College of Medicine, Fu Jen Catholic University, Taipei, Taiwan Objectives: The main purpose of this study was to investigate whether carotid artery stenting (CAS plus medicine in patients with severe carotid artery stenosis provide a better long-term blood pressure (BP control compared to other medical treatments alone. The other aim was to explore the correlation between post-CAS hypotension within 6 h and long-term BP reductions after CAS. Materials and methods: Patients with severe carotid stenosis were recruited either in the CAS group or in the medication group. BPs and the number of classes of antihypertensive agents were recorded at baseline, 6, and 12 months. Extra BP information was collected at 6 h, 3 days, and 1 month after CAS. Univariate and multivariate linear regressions were performed to test the relationship of BP changes among CAS and medication groups after 6 and 12 months of follow-up. Univariate linear regressions were also used to determine the correlations between the mean or maximal systolic BP (SBP reductions at 6 h and 1 year post-CAS. Results: In total, 72 members in the CAS group and 82 members in the medication group were recruited. Compared with the medication group, patients in the CAS group had greater BP reductions at 6 and 12 months of follow-up after adjusting for confounding factors (13.56 mmHg at 6 months, P=0.0002; 16.98 mmHg at 12 months, P<0.0001. This study also shows significant

  15. Nitric Oxide Increases Arterial Endotheial Permeability through Mediating VE-Cadherin Expression during Arteriogenesis.

    Directory of Open Access Journals (Sweden)

    Baolin Yang

    Full Text Available Macrophage invasion is an important event during arteriogenesis, but the underlying mechanism is still only partially understood. The present study tested the hypothesis that nitric oxide (NO and VE-cadherin, two key mediators for vascular permeability, contribute to this event in a rat ischemic hindlimb model. In addition, the effect of NO on expression of VE-caherin and endothelial permeability was also studied in cultured HUVECs. We found that: 1 in normal arteriolar vessels (NAV, eNOS was moderately expressed in endothelial cells (EC and iNOS was rarely detected. In contrast, in collateral vessels (CVs induced by simple femoral artery ligation, both eNOS and iNOS were significantly upregulated (P<0.05. Induced iNOS was found mainly in smooth muscle cells, but also in other vascular cells and macrophages; 2 in NAV VE-cadherin was strongly expressed in EC. In CVs, VE-cadherin was significantly downregulated, with a discontinuous and punctate pattern. Administration of nitric oxide donor DETA NONOate (NONOate further reduced the amounts of Ve-cadherin in CVs, whereas NO synthase inhibitor L-NAME inhibited downregulation of VE-cadherin in CVs; 3 in normal rats Evans blue extravasation (EBE was low in the musculus gracilis, FITC-dextron leakage was not detected in the vascular wall and few macrophages were observed in perivascular space. In contrast, EBE was significantly increased in femoral artery ligation rats, FITC-dextron leakage and increased amounts of macrophages were detected in CVs, which were further enhanced by administration of NONOate, but inhibited by L-NAME supplement; 4 in vitro experiments confirmed that an increase in NO production reduced VE-cadherin expression, correlated with increases in the permeability of HUVECs. In conclusion, our data for the first time reveal the expression profile of VE-cadherin and alterations of vascular permeability in CVs, suggesting that NO-mediated VE-cadherin pathway may be one important

  16. Temporary arterial stenting in a full-house spaghetti wrist injury in a remote rural setting: benefit for hand perfusion or risk of increased morbidity?

    Science.gov (United States)

    Bauer, Stefan; Savundra, James

    2013-01-01

    We report a case of temporary arterial plastic tube stenting of the ulnar and radial artery in a complete spaghetti wrist injury in a remote rural setting. Exploration in a specialist centre 18 h postinjury revealed that the tubes were clotted off with adjacent thrombi but hand perfusion was maintained. Intimal damage required vein grafting of both arteries 24 h postinjury. Hand perfusion was not compromised at follow-up. This case highlights that arterial hand perfusion can be maintained without the ulnar and radial artery. Arterial manipulation and tube insertion outside a specialist centre bears the risk of increased morbidity and potential microembolism and must therefore not be attempted.

  17. Inadvertent arterial insertion of a central venous catheter: delayed recognition with abrupt changes in pressure waveform during surgery -A case report-.

    Science.gov (United States)

    Choi, Yong Sun; Park, Ji Young; Kwak, Young Lan; Lee, Jong Wha

    2011-01-01

    We present a case of inadvertent arterial insertion of a central venous catheter, identified during a pericardiectomy procedure after observing abrupt changes in pressure waveform and confirmed via arterial blood gas analysis and transesophageal echocardiography. Central venous pressure measurement was initially 20 mmHg in supine, and then elevated to 30-40 mmHg in right lateral decubitus, presumably resulting from constrictive physiology of pericarditis. The pressure waveforms, however, abruptly changed from a venous to an arterial waveform during surgery. When visual discrimination between arterial and venous blood regurgitation is unreliable, anesthesiologists should confirm that using all the available methods one has on the scene, especially after at least two unsuccessful attempts or in patients with advanced age or clinical conditions resulting in jugular venous dilation. To prevent arterial catheterization, one should limit the leftward rotation of the head by <40° and consider using ultrasound-guided method after more than two unsuccessful attempts.

  18. Excess salt increases infarct size produced by photothrombotic distal middle cerebral artery occlusion in spontaneously hypertensive rats.

    Directory of Open Access Journals (Sweden)

    Hiroshi Yao

    Full Text Available Cerebral circulation is known to be vulnerable to high salt loading. However, no study has investigated the effects of excess salt on focal ischemic brain injury. After 14 days of salt loading (0.9% saline or water, spontaneously hypertensive rats (SHR and normotensive Wistar-Kyoto rats (WKY were subjected to photothrombotic middle cerebral artery occlusion (MCAO, and infarct volume was determined at 48 h after MCAO: albumin and hemoglobin contents in discrete brain regions were also determined in SHR. Salt loading did not affect blood pressure levels in SHR and WKY. After MCAO, regional cerebral blood flow (CBF, determined with two ways of laser-Doppler flowmetry (one-point measurement or manual scanning, was more steeply decreased in the salt-loaded group than in the control group. In SHR/Izm, infarct volume in the salt-loaded group was 112±27 mm3, which was significantly larger than 77±12 mm3 in the control group (p = 0.002, while the extents of blood-brain barrier disruption (brain albumin and hemoglobin levels were not affected by excess salt. In WKY, salt loading did not significantly increase infarct size. These results show the detrimental effects of salt loading on intra-ischemic CBF and subsequent brain infarction produced by phototrhombotic MCAO in hypertensive rats.

  19. Desflurane increases intracranial pressure more and sevoflurane less than isoflurane in pigs subjected to intracranial hypertension.

    Science.gov (United States)

    Holmström, Anders; Akeson, J

    2004-04-01

    Desflurane and sevoflurane may have advantages over isoflurane in neuroanesthesia, but this is still under debate. A porcine model with experimental intracranial hypertension was used for paired comparison of desflurane, sevoflurane, and isoflurane with respect to the effects on cerebral blood flow (CBF), cerebrovascular resistance (CVR), and intracranial pressure (ICP). The agents, given in sequence to each of six pigs, were compared at 0.5 and 1.0 minimal alveolar concentrations (MAC) and three mean arterial blood pressure (MAP) levels (50, 70, and 90 mm Hg) at normocapnia and one MAP level (70 mm Hg) at hypocapnia. MAC for each agent had been previously determined in a standardized manner for comparison reliability. CBF was measured with Xe. MAP was lowered by inflation of a balloon catheter in the inferior caval vein and raised by inflation of a balloon catheter in the descending aorta. ICP was measured intraparenchymally. Two Fogarty catheters positioned extradurally were inflated to a baseline ICP of 20 to 22 mm Hg at 0.2 MAC of each agent. CBF and ICP with the three agents at normocapnia and MAP 70 and 90 mm Hg at both 0.5 and 1.0 MAC were as follows (P isoflurane > sevoflurane. None of the agents abolished CO2 reactivity. High-dose desflurane resulted in a higher CBF at hypocapnia than corresponding doses of sevoflurane or isoflurane, but there were no significant differences between the agents in ICP at hypocapnia. The present study showed that desflurane increased ICP more and sevoflurane less than isoflurane during normoventilation, but the differences disappeared with hyperventilation.

  20. Long term survival of patients with raised pulmonary arterial systolic pressure utilizing echocardiography—a five-year prospective study

    Institute of Scientific and Technical Information of China (English)

    Maw Pin Tan; Sushil K Bansal; Nu Nu Wynn; Murad Umerov; Angela Gillham; Alison Henderson; Anthony Hildreth; Shahid Junejo

    2012-01-01

    Background Pulmonary arterial systolic pressure (PASP) can be estimated with transthoracic echocardiography. However, the significance of raised PASP on routine echocardiography is uncertain. In this study, we evaluated the mortality and hospitalization rates of subjects with raised PASP in a cohort of patients referred directly by their general practitioners for routine outpatient (open access)echocardiography for further analysis of suspected heart failure. Results A total of 485 subjects were referred for open access echocardiography at our hospital in 2002. A cohort of 209/485 (43%) consecutive subjects with measurable tricuspid regurgitation were followed for a minimum of five years investigating hospitalization rates and survival. Some 62 of 209 (30%) subjects had pulmonary hypertension (PH). Subjects with PH were significantly more likely to have four or more hospital admissions (22% vs. 8%; P 30 days of cumulative hospital stay over five years (29% vs. 13%; P < 0.01). PH was significantly associated with mortality (P = 0.003),Records from the Office of National Statistics revealed that subjects with PH were more likely to have chronic lung diseases recorded as immediate or contributory causes of death (50% vs. 14%; P < 0.05). Conclusions PASP ≥ 36 mmHg on routine echocardiography is associated with recurrent hospital admissions, prolonged hospitalizations and increased cause of mortality. Therefore, the diagnosis of PH on echocardiography deserves further clinical evaluation, with future studies designed at defining a suitable diagnostic strategy.

  1. A longitudinal study of arterial blood pressure in chronic haemodialysis patients with different levels of plasma renin concentration.

    Science.gov (United States)

    Kornerup, H J; Fredsted, B; Pedersen, R S

    1978-01-01

    The purpose of the study was to examine the value of regular measurements of plasma renin concentration (PRC) in selecting those chronic haemodialysis patients suitable for bilateral nephrectomy to prevent development of uncontrollable hypertension. Regular measurements of arterial blood pressure (BP) and PRC were performed during one year in 31 patients undergoing regular haemodialysis because of end-stage renal disease. Among 18 patients with PRC greater than or equal to 100 micro Goldblatt units per ml plasma (microGU/ml) systolic and/or diastolic hypertension persisted or developed in 12. In contrast, among 13 patients with PRC greater than 100microGU/ml, BP became normal in all but one, who had a slightly increased systolic BP. However, hypertension was mild and easily controlled by conventional therapy in all except one, who probably had an overlying volume-dependent hypertension. Therefore, bilateral nephrectomy was not necessary in any case. The results indicate that hypertension in the majority of chronic haemodialysis patients with high PRC can be adequately controlled without surgical intervention and that regular measurements of PRC have no practical value in forecasting the development of uncontrollable hypertension in chronic haemodialysis patients.

  2. [Influence of treatment with olmesartan on ambulatory blood pressure monitoring parameters in patients with arterial hypertension].

    Science.gov (United States)

    Bregvadze, T R; Tseluĭko, V I; Mishchuk, N E

    2013-12-01

    Hypertension is the most common disease of the cardiovascular system. Active treatment of hypertension with adequate control of blood pressure (BP) can prevent complications, improve life quality and increase life expectancy. One of the interesting new antihypertensive agents, from the group of angiotensin receptor blockers is olmesartan. The obvious advantages of ambulatory blood pressure monitoring to traditional one-time measurements of BP make this method perspective for quality control of anti-hypertensive therapy. The aim of this study was to evaluate the influence of treatment with olmesartan on ambulatory blood pressure monitoring parameters in patients with hypertension. 38 out-patients with hypertension at the age of 25-84 years (mean 55,3±10,6) were studied. Patients received olmesartan 20 mg daily as monotherapy (20 patients (52,6%)) or in combination with other antihypertensive agents (18 patients (47,4%)). Treatment continued for 6 months. The complex examination included: measurement of office brachial BP, electrocardiography, echocardiography and ambulatory blood pressure monitoring (ABPM). As a result of treatment, office BP and diurnal BP, according to ABPM, significantly decreased; the favorable circadian BP profile dynamics were found: significantly less frequently observed lack of reduction in BP during night (daily index - non-dipper) - 18% vs. 64% (p treatment of hypertensive patients with olmesartan provides significant decline not only in office BP, but also in diurnal BP, normalizes BP of active and passive periods, also - daily index and reduces BP variability.

  3. Myosin heavy chain 15 is associated with bovine pulmonary arterial pressure

    Science.gov (United States)

    Neary, Joseph M.; Lund, Gretchen K.; Holt, Timothy N.; Garry, Franklyn B.; Mohun, Timothy J.; Breckenridge, Ross A.

    2014-01-01

    Abstract Bovine pulmonary hypertension, brisket disease, causes significant morbidity and mortality at elevations above 2,000 m. Mean pulmonary arterial pressure (mPAP) is moderately heritable, with inheritance estimated to lie within a few major genes. Invasive mPAP measurement is currently the only tool available to identify cattle at risk of hypoxia-induced pulmonary hypertension. A genetic test could allow selection of cattle suitable for high altitude without the need for invasive testing. In this study we evaluated three candidate genes (myosin heavy chain 15 [MYH15], NADH dehydrogenase flavoprotein 2, and FK binding protein 1A) for association with mPAP in 166 yearling Angus bulls grazing at 2,182 m. The T allele (rs29016420) of MYH15 was linked to lower mPAP in a dominant manner (CC 47.2 ± 1.6 mmHg [mean ± standard error of the mean]; CT/TT 42.8 ± 0.7 mmHg; P = 0.02). The proportions of cattle with MYH15 CC, CT, and TT genotypes were 55%, 41%, and 4%, respectively. Given the high frequency of the deleterious allele, it is likely that the relative contribution of MYH15 polymorphisms to pulmonary hypertension is small, supporting previous predictions that the disease is polygenic. We evaluated allelic frequency of MYH15 in the Himalayan yak (Bos grunniens), a closely related species adapted to high altitude, and found 100% prevalence of T allele homozygosity. In summary, we identified a polymorphism in MYH15 significantly associated with mPAP. This finding may aid selection of cattle suitable for high altitude and contribute to understanding human hypoxia-induced pulmonary hypertension. PMID:25621163

  4. Bilayered negative-pressure wound therapy preventing leg incision morbidity in coronary artery bypass graft patients

    Science.gov (United States)

    Yu, Yongchao; Song, Zhigang; Xu, Zhiyun; Ye, Xiaofei; Xue, Chunyu; Li, Junhui; Bi, Hongda

    2017-01-01

    Abstract Backgrounds: The harvesting of great saphenous veins for coronary artery bypass graft (CABG) patients may result in significant complications, including lymphorrhagia, lymphoedema, incision infection, wound dehiscence, and skin flap necrosis. We investigated the function of a self-designed bilayered negative pressure wound therapy (b-NPWT) for reducing the above-mentioned complications using a clinical randomized controlled trial. Methods: A single-center, pilot randomized controlled trial was conducted. From December 2013 to March 2014, a total of 72 coronary heart disease patients (48 men and 24 women) received CABG therapy, with great saphenous veins were selected as grafts. Patients were equally randomized into a treatment and a control group. After the harvesting of the great saphenous veins and direct closure of the wound with sutures, b-NPWT was used for the thigh incision in the treatment group for 5 days (treatment thigh). Traditional surgical pads were applied to both the shank incisions of the treatment group patients (treatment shank) and the entire incisions of the control group (control thigh, control shank). Postoperative complications were recorded and statistically analyzed based on outcomes of thigh treatment, shank treatment, thigh control, and shank control groups. Results: The incidence rates of early complications, such as lymphorrhagia, lymphoedema, infection, wound dehiscence, and skin flap necrosis, of the vascular donor site in the thigh treatment group was significantly lower than those in the 3 other groups. Conclusions: The self-designed b-NPWT can effectively reduce postoperative complications, such as lymphedema, incision infection, wound dehiscence, and skin flap necrosis, in CABG patients who underwent great saphenous veins harvesting. Trial registration: ClinicalTrials.gov. The unique registration number is NCT02010996. PMID:28099357

  5. Myosin heavy chain 15 is associated with bovine pulmonary arterial pressure.

    Science.gov (United States)

    Neary, Marianne T; Neary, Joseph M; Lund, Gretchen K; Holt, Timothy N; Garry, Franklyn B; Mohun, Timothy J; Breckenridge, Ross A

    2014-09-01

    Bovine pulmonary hypertension, brisket disease, causes significant morbidity and mortality at elevations above 2,000 m. Mean pulmonary arterial pressure (mPAP) is moderately heritable, with inheritance estimated to lie within a few major genes. Invasive mPAP measurement is currently the only tool available to identify cattle at risk of hypoxia-induced pulmonary hypertension. A genetic test could allow selection of cattle suitable for high altitude without the need for invasive testing. In this study we evaluated three candidate genes (myosin heavy chain 15 [MYH15], NADH dehydrogenase flavoprotein 2, and FK binding protein 1A) for association with mPAP in 166 yearling Angus bulls grazing at 2,182 m. The T allele (rs29016420) of MYH15 was linked to lower mPAP in a dominant manner (CC 47.2 ± 1.6 mmHg [mean ± standard error of the mean]; CT/TT 42.8 ± 0.7 mmHg; P = 0.02). The proportions of cattle with MYH15 CC, CT, and TT genotypes were 55%, 41%, and 4%, respectively. Given the high frequency of the deleterious allele, it is likely that the relative contribution of MYH15 polymorphisms to pulmonary hypertension is small, supporting previous predictions that the disease is polygenic. We evaluated allelic frequency of MYH15 in the Himalayan yak (Bos grunniens), a closely related species adapted to high altitude, and found 100% prevalence of T allele homozygosity. In summary, we identified a polymorphism in MYH15 significantly associated with mPAP. This finding may aid selection of cattle suitable for high altitude and contribute to understanding human hypoxia-induced pulmonary hypertension.

  6. In vivo evaluation of a novel, wrist-mounted arterial pressure sensing device versus the traditional hand-held tonometer.

    Science.gov (United States)

    Vardoulis, Orestis; Saponas, T Scott; Morris, Dan; Villar, Nicolas; Smith, Greg; Patel, Shwetak; Tan, Desney

    2016-10-01

    Although hemodynamic parameters can be assessed non-invasively, state-of-the-art non-invasive systems generally require an expert operator and are not applicable for ambulatory measurements. These limitations have restricted our understanding of the continuous behavior of hemodynamic parameters. In this manuscript, we introduce a novel wrist-mounted device that incorporates an array of pressure sensors which can be used to extract arterial waveforms and relevant pulse wave analysis biomarkers. In vivo evaluation is performed with Bland-Altman analysis to compare the novel sensor to a gold-standard hand-held tonometer by assessing their reproducibility and agreement in peripheral augmentation index (AIx) estimation at the radial artery. Arterial waves from 28 randomly selected participants were recorded in a controlled environment. Initially we assess the reproducibility of AIx results for both devices. The intra-class correlation coefficient (ICC) and mean difference ± SD were [0.913, 0.033±0.048] and [0.859, 0.039±0.076] for the hand-held and the wrist-mounted tonometer respectively. We then show that the AIx values derived from the novel tonometer have good agreement, accuracy, and precision when compared against the AIx values derived from the reference hand-held tonometer (ICC 0.927, mean difference 0.026±0.049). In conclusion, we have presented evidence that the new wrist-mounted arterial pressure sensor records arterial waveforms that can be processed to yield AIx values that are in good agreement with its traditional hand-held counterpart.

  7. Clinical and psychological characteristics of patients with arterial hypertension, consuming an increased amount of salt

    Directory of Open Access Journals (Sweden)

    O. B. Poselyugina

    2015-01-01

    Full Text Available Objective: to Study the potential development of links between the formation of neurotic disorders personality and high salt intake (S with food in patients with arterial hypertension (AH.Materials and methods: the study involved 229 patients with essential hypertension. We determined the threshold of taste sensitivity to salt (TTS, the daily excretion of sodium ions in urine, was assessed psychological status of the patients, the type of attitude to the disease (LOBI, the severity of depression (Beck questionnaire.Results. It turned out that people consume AH TTS is much more than a healthy person. Patients consuming an increased amount of S, the disease develops earlier and runs a more aggressive accompanied by the emergence of a large number of neurotic complaints and cardiovascular nature. Their psychological status is dominated by anxiety and tension. Almost half of these patients have depression. Harmonious type of attitude to the disease occurs in them only in 1/3 of the cases, whereas a dominant role is played by neurotic and anxious types.Conclusions: Patients with hypertension high consumption of S represent a distinct group of patients in whom an increased intake of salt simulates the course of their illness and promotes the development of certain psychological characteristics.

  8. Mild and moderate pre-dialysis chronic kidney disease is associated with increased coronary artery calcium

    Directory of Open Access Journals (Sweden)

    Budoff M

    2011-12-01

    Full Text Available Sion K Roy, Albert Cespedes, Dong Li, Tae-Young Choi, Matthew J BudoffDivision of Cardiology, Department of Medicine, Los Angeles Biomedical Research Center at Harbor-UCLA Medical Center, Torrance, California, USABackground: It is increasingly evident that patients with chronic kidney disease (CKD are more likely to die from heart disease than kidney failure. This study evaluated whether pre-dialysis CKD is an independent risk factor for coronary artery calcium (CAC.Methods: A total of 544 consecutive patients who underwent CAC scoring were analyzed. Eleven patients requiring hemodialysis were excluded. Patients were divided into three groups: normal glomerular filtration rate (GFR (GFR > 90 mL/min/1.73 m2, mild CKD (90 ≥ GFR > 60 mL/min/1.73 m2, and moderate CKD (60 ≥ GFR > 30 mL/min/1.73 m2. Continuous and categorical variables were compared using analysis of variance and the χ2 statistic. A multiple logistic regression model was used for detecting the association between total CAC score and GFR. An unadjusted model was used, followed by a second model adjusted for covariates known to be related to CAC. Another multivariable binary logistic model predicting the presence of CAC (>10 was performed and odds of incidence of CAC (>10 were calculated among the three GFR subgroups.Results: After adjustment for covariates, patients with mild CKD had mean CAC scores 175 points higher than those with the referent normal GFR (P = 0.048, while those with moderate CKD had mean CAC scores 693 points higher than the referent (P < 0.001. After adjustment for covariates, patients with mild CKD were found to be 2.2 times more likely (95% confidence interval 1.3–3.7, P = 0.004 and patients with moderate CKD were 6.4 times more likely (95% confidence interval 2.9–14.3, P < 0.001 to have incident CAC compared with the group with normal GFR.Conclusion: Mild and moderate pre-dialysis CKD are independent risk factors for increased mean and incident CAC

  9. Artery by Neuropeptides

    Directory of Open Access Journals (Sweden)

    Esmeralda Sofia Costa Delgado

    2012-01-01

    Methods. Isolated rabbit eyes (n=12 were perfused in situ with tyrode through the external ophthalmic artery. Effects of intra-arterial injections of NPY 200 μg/ml (Group A; n=6 and VIP 200 μg/ml (Group B; n=6 on the recorded pressure were obtained. For statistical analysis, Student's paired t-test and Fast Fourier Transform were used. Results. Spontaneous oscillations were observed before any drug administration in the 12 rabbit models. NPY produced an increase in total vascular resistance and a higher frequency and amplitude of oscillations, while VIP evoked the opposite effects. Conclusions. This study provides evidence of vasomotion in basal conditions in rabbit external ophthalmic artery. Concerning drug effects, NPY increased arterial resistance and enhanced vasomotion while VIP produced opposite effects which demonstrates their profound influence in arterial vasomotion.

  10. Drought Increases Consumer Pressure on Oyster Reefs in Florida, USA.

    Science.gov (United States)

    Garland, Hanna G; Kimbro, David L

    2015-01-01

    Coastal economies and ecosystems have historically depended on oyster reefs, but this habitat has declined globally by 85% because of anthropogenic activities. In a Florida estuary, we investigated the cause of newly reported losses of oysters. We found that the oyster reefs have deteriorated from north to south and that this deterioration was positively correlated with the abundance of carnivorous conchs and water salinity. In experiments across these gradients, oysters survived regardless of salinity if conchs were excluded. After determining that conchs were the proximal cause of oyster loss, we tested whether elevated water salinity was linked to conch abundance either by increasing conch growth and survivorship or by decreasing the abundance of a predator of conchs. In field experiments across a salinity gradient, we failed to detect spatial variation in predation on conchs or in conch growth and survivorship. A laboratory experiment, however, demonstrated the role of salinity by showing that conch larvae failed to survive at low salinities. Because this estuary's salinity increased in 2006 in response to reduced inputs of freshwater, we concluded that the ultimate cause of oyster decline was an increase in salinity. According to records from 2002 to 2012, oyster harvests have remained steady in the northernmost estuaries of this ecoregion (characterized by high reef biomass, low salinity, and low conch abundance) but have declined in the southernmost estuaries (characterized by lower reef biomass, increases in salinity, and increases in conch abundance). Oyster conservation in this ecoregion, which is probably one of the few that still support viable oyster populations, may be undermined by drought-induced increases in salinity causing an increased abundance of carnivorous conchs.

  11. Inverting Notions of the Biological Role of the Renin → Angiotensin-II → Aldosterone System and the Function of Arterial Pressure as a Metabolism Regulator

    Directory of Open Access Journals (Sweden)

    Vladimir N. Titov

    2014-09-01

    Full Text Available The phylogenetic theory of general pathology postulates that notions of the biological role of arterial pressure (AP in physiology and pathology have been subjected to inversion. The nephron’s activation of the synthesis of the components renin → angiotensin-II (A-II and the augmentation of aldosterone secretion are directed not at an increase in AP but at preserving the volume of the piece of the third world ocean, privatized by each species, - the pool of the intercellular milieu in which, just like millions of years before, there continue to live all cells. Phylogenetically earlier organs cannot regulate the action of a later one in AP phylogenesis – a physical factor in metabolism regulation. It is not the kidneys that increase AP but the vasomotor center, which, increasing AP in the proximal segment and further hydrodynamic pressure in the distal segment of the arterial bed, seeks to reanimate the function of nephrons, the biological function of endoecology and the biological reaction of excretion. In addition to playing a major role in the biological function of locomotion, AP is a physical factor in compensating for impairments in the biological functions of homeostasis, trophology, endoecology, and adaptation. There have formed sequentially three levels of metabolic regulation in phylogenesis. At an autocrine level, there occurs a specific regulation of biochemical reactions. Within paracrinally regulated communities of cells, in the distal segment of the arterial bed, metabolism is regulated by millions of local peristaltic pumps through compensating for the biological reaction of endothelium-dependent vasodilation, microcirculation, and the action of humoral mediators and hormonal principles. In vivo from the level of the vasomotor center metabolism is non-specifically, systemically regulated by the physical factor – AP – through sympathetic activation of the heart; in the proximal segment of the arterial bed and the distal

  12. A fluid-structure interaction model of the internal carotid and ophthalmic arteries for the noninvasive intracranial pressure measurement method.

    Science.gov (United States)

    Misiulis, Edgaras; Džiugys, Algis; Navakas, Robertas; Striūgas, Nerijus

    2017-03-22

    Accurate and clinically safe measurements of intracranial pressure (ICP) are crucial for secondary brain damage prevention. There are two methods of ICP measurement: invasive and noninvasive. Invasive methods are clinically unsafe; therefore, safer noninvasive methods are being developed. One of the noninvasive ICP measurement methods implements the balance principle, which assumes that if the velocity of blood flow in both ophthalmic artery segments - the intracranial (IOA) and extracranial (EOA) - is equal, then the acting ICP on the IOA and the external pressure (Pe) on the EOA are also equal. To investigate the assumption of the balance principle, a generalized computational model incorporating a fluid-structure interaction (FSI) module was created and used to simulate noninvasive ICP measurement by accounting for the time-dependent behavior of the elastic internal carotid (ICA) and ophthalmic (OA) arteries and their interaction with pulsatile blood flow. It was found that the extra balance pressure term, which incorporates the hydrodynamic pressure drop between measurement points, must be added into the balance equation, and the corrections on a difference between the velocity of blood flow in the IOA and EOA must be made, due to a difference in the blood flow rate.

  13. Increased Plasma Dipeptidyl Peptidase-4 Activities in Patients with Coronary Artery Disease

    Science.gov (United States)

    Yang, Guang; Li, Yuzi; Cui, Lan; Jiang, Haiying; Li, Xiang; Jin, Chunzi; Jin, Dehao; Zhao, Guangxian; Jin, Jiyong; Sun, Rui; Piao, Limei; Xu, Wenhu; Fang, Chenghu; Lei, Yanna; Yuan, Kuichang; Xuan, Chunhua; Ding, Dazi

    2016-01-01

    Dipeptidyl peptidase-4 (DPP4) is one of the most potent mammalian serine proteases participated in the pathogenesis of subclinical atherosclerosis. Here we investigated whether the plasma soluble form of DPP4 is associated with the prevalence of coronary artery disease (CAD) with and without diabetes mellitus (DM). A cross-sectional study was conducted of 496 aged 26–81 years with (n = 362) and without (n = 134) CAD. Plasma DPP4 activity, high sensitive C-reactive protein (hs-CRP), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein levels were measured. The coronary atherosclerotic plaques were evaluated by coronary angiography. The CAD patients with (n = 84) and without (n = 278) DM had significantly higher DPP4 levels (11.8 ± 3.1 vs. 6.9 ± 3.5 ng/mL, Psyntax scores. A multiple logistic regression analysis demonstrated that plasma DPP4 activity was independent predictor of CAD (odds ratio, 1.56; 95% CI, 1.19–1.73; P<0.01). Our study shows that increased DPP4 activity levels are associated with the presence of CAD and that the plasma DPP4 level serves as a novel biomarker for CAD even without DM. PMID:27654253

  14. Increased circulating monocyte count is related to good collateral development in coronary artery disease.

    Science.gov (United States)

    Kocaman, Sinan Altan; Arslan, Uğur; Tavil, Yusuf; Okuyan, Hizir; Abaci, Adnan; Cengel, Atiye

    2008-04-01

    Monocytes have been shown to take an important role in collateral growth in animal studies. The aim of the study was to investigate the relation of circulating monocyte count with collateral development in patients with severely stenotic CAD. Patients who had > or =95% stenosis in at least one major coronary artery were included in the study. Coronary angiograms of 210 eligible patients from our database were analyzed again and 103 of them had good and 107 had poor collateral development according to Cohen-Rentrop method. Only the monocyte count was found to be significantly different between two groups (671+/-218 mm(-3) versus 522+/-195 mm(-3), p<0.001) when multivariate analysis was performed and an increased monocyte count was observed in the good collateral group (Odds ration [OR], 2.918; 95% confidence interval [CI], 1.281-6.648, p=0.011). This study in which the relationship between monocyte count in blood and collateral development was disclosed has a potential importance in clinical and basic cardiovascular medicine.

  15. The mixing rate of the arterial blood pressure waveform Markov chain is correlated with shock index during hemorrhage in anesthetized swine.

    Science.gov (United States)

    Adibuzzaman, Mohammad; Kramer, George C; Galeotti, Loriano; Merrill, Stephen J; Strauss, David G; Scully, Christopher G

    2014-01-01

    Identifying the need for interventions during hemorrhage is complicated due to physiological compensation mechanisms that can stabilize vital signs until a significant amount of blood loss. Physiological systems providing compensation during hemorrhage affect the arterial blood pressure waveform through changes in dynamics and waveform morphology. We investigated the use of Markov chain analysis of the arterial blood pressure waveform to monitor physiological systems changes during hemorrhage. Continuous arterial blood pressure recordings were made on anesthetized swine (N=7) during a 5 min baseline period and during a slow hemorrhage (10 ml/kg over 30 min). Markov chain analysis was applied to 20 sec arterial blood pressure waveform segments with a sliding window. 20 ranges of arterial blood pressure were defined as states and empirical transition probability matrices were determined for each 20 sec segment. The mixing rate (2(nd) largest eigenvalue of the transition probability matrix) was determined for all segments. A change in the mixing rate from baseline estimates was identified during hemorrhage for each animal (median time of 13 min, ~10% estimated blood volume, with minimum and maximum times of 2 and 33 min, respectively). The mixing rate was found to have an inverse correlation with shock index for all 7 animals (median correlation coefficient of -0.95 with minimum and maximum of -0.98 and -0.58, respectively). The Markov chain mixing rate of arterial blood pressure recordings is a novel potential biomarker for monitoring and understanding physiological systems during hemorrhage.

  16. Effect of continuous positive airway pressure treatment on serum adiponectin level and mean arterial pressure in male patients with obstructive sleep apnea syndrome

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xi-long; YIN Kai-sheng; LI Chong; JIA En-zhi; LI Yan-qun; GAO Zhao-fang

    2007-01-01

    Background Recent research suggested that obstructive sleep apnea syndrome (OSAS) might be independently associated with hypoadiponectinemia, which was linked to some complications of OSAS, such as hypertension, diabetes,etc. This study was conducted to investigate the effect of continuous positive airway pressure (CPAP) treatment on changes of both serum adiponectin levels and mean arterial pressure and their possible links in male OSAS patients.Methods Twenty-three adult male patients with moderate-to-severe OSAS but without obesity, coronary heart disease and diabetes were recruited. Their blood sampleswere collected and moming mean arterial pressure (MAP) was measured before CPAP treatment and on day 3, 7, 14 of CPAP treatment respectively. The serum adiponectin concentration was tested with radioimmunoassay.Results Compared with the serum adiponectin level before CPAP treatment, no significant change was found in OSAS patients on day 3 and day 7 of CPAP treatment (P>0.05). It was not until day 14 of CPAP treatment did a significant elevation in serum adiponectin level occur (P<0.01). Meanwhile, the MAP showed no statistically significant difference among its levels before CPAP, on day 3 and day 7 of CPAP treatment (P>0.05). However, on day 14 of CPAP treatment,a significantly lower MAP than that obtained before treatment was observed (P<0.05).Conclusions CPAP treatment can gradually reverse hypoadiponectinemia and reduce MAP in OSAS patients.Hypoadiponectinemia might be involved in the pathogenesis of OSAS-mediated hypertension.

  17. Patient-Specific Simulation of Coronary Artery Pressure Measurements: An In Vivo Three-Dimensional Validation Study in Humans

    Directory of Open Access Journals (Sweden)

    Panagiotis K. Siogkas

    2015-01-01

    Full Text Available Pressure measurements using finite element computations without the need of a wire could be valuable in clinical practice. Our aim was to compare the computed distal coronary pressure values with the measured values using a pressure wire, while testing the effect of different boundary conditions for the simulation. Eight coronary arteries (lumen and outer vessel wall from six patients were reconstructed in three-dimensional (3D space using intravascular ultrasound and biplane angiographic images. Pressure values at the distal and proximal end of the vessel and flow velocity values at the distal end were acquired with the use of a combo pressure-flow wire. The 3D lumen and wall models were discretized into finite elements; fluid structure interaction (FSI and rigid wall simulations were performed for one cardiac cycle both with pulsatile and steady flow in separate simulations. The results showed a high correlation between the measured and the computed coronary pressure values (coefficient of determination [r2] ranging between 0.8902 and 0.9961, while the less demanding simulations using steady flow and rigid walls resulted in very small relative error. Our study demonstrates that computational assessment of coronary pressure is feasible and seems to be accurate compared to the wire-based measurements.

  18. AGE, ARTERIAL STIFFNESS AND CARDIOVASCULAR RISK

    Institute of Scientific and Technical Information of China (English)

    蒋雄京; 刘国仗; 刘力生

    2001-01-01

    The recent researches on the structure and function of large artery find that increasing pulse pressure is associated with greater cardiovascular risk, especially risk of coronary events. Such risk is not explicable on the basis of increasing systolic pressure with age, and is apparent even when the major reason for increased pulse pressure is a relative decrease of diastolic pressure. The finding challenges the conventional approach to arterial pressure where diastolic pressure is traditionally viewed as the most robust indicator of caridovascular risk. An explanation is available. This is based on the perception of Harriet Dustan that hypertension in the older popula-

  19. Exercise increases pressure pain tolerance but not pressure and heat pain thresholds in healthy young men

    DEFF Research Database (Denmark)

    Vaegter, H. B.; Bement, M. Hoeger; Madsen, A. B.

    2017-01-01

    BACKGROUND: Exercise causes an acute decrease in the pain sensitivity known as exercise-induced hypoalgesia (EIH), but the specificity to certain pain modalities remains unknown. This study aimed to compare the effect of isometric exercise on the heat and pressure pain sensitivity. METHODS: On th...

  20. Renal Denervation Normalizes Arterial Pressure With No Effect on Glucose Metabolism or Renal Inflammation in Obese Hypertensive Mice.

    Science.gov (United States)

    Asirvatham-Jeyaraj, Ninitha; Fiege, Jessica K; Han, Ruijun; Foss, Jason; Banek, Christopher T; Burbach, Brandon J; Razzoli, Maria; Bartolomucci, Alessandro; Shimizu, Yoji; Panoskaltsis-Mortari, Angela; Osborn, John W

    2016-10-01

    Hypertension often occurs in concurrence with obesity and diabetes mellitus, commonly referred to as metabolic syndrome. Renal denervation (RDNx) lowers arterial pressure (AP) and improves glucose metabolism in drug-resistant hypertensive patients with high body mass index. In addition, RDNx has been shown to reduce renal inflammation in the mouse model of angiotensin II hypertension. The present study tested the hypothesis that RDNx reduces AP and renal inflammation and improves glucose metabolism in obesity-induced hypertension. Eight-week-old C57BL/6J mice were fed either a low-fat diet (10 kcal%) or a high-fat diet (45 kcal%) for 10 weeks. Body weight, food intake, fasting blood glucose, and glucose metabolism (glucose tolerance test) were measured. In a parallel study, radiotelemeters were implanted in mice for AP measurement. High fat-fed C57BL/6J mice exhibited an inflammatory and metabolic syndrome phenotype, including increased fat mass, increased AP, and hyperglycemia compared with low-fat diet mice. RDNx, but not Sham surgery, normalized AP in high-fat diet mice (115.8±1.5 mm Hg in sham versus 96.6±6.7 mm Hg in RDNx). RDNx had no significant effect on AP in low-fat diet mice. Also, RDNx had no significant effect on glucose metabolism or renal inflammation as measured by the number of CD8, CD4, and T helper cells or levels of inflammatory cytokines in the kidneys. These results indicate that although renal nerves play a role in obesity-induced hypertension, they do not contribute to impaired glucose metabolism or renal inflammation in this model.

  1. Continuous flow augments reactivity of rabbit carotid artery by reducing bioavailability of NO despite an increase in release of EDHF

    DEFF Research Database (Denmark)

    Rasmussen, Lasse Enkebølle; Vanhoutte, Paul M. G.; Jensen, Boye L.

    2006-01-01

    of endothelial small- and intermediate-conductance calcium-activated potassium channels by apamin plus 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34). These experiments demonstrate that continuous flow increases the constriction evoked by alpha(1)-adrenergic activation in the rabbit carotid artery...

  2. Increased Contractile Response to Noradrenaline Induced By Factors Associated with the Metabolic Syndrome in Cultured Small Mesenteric Arteries

    DEFF Research Database (Denmark)

    Blædel, Martin; Sams, Anette; Boonen, Harrie C M

    2016-01-01

    UNLABELLED: This study investigated the effect of the metabolic syndrome associated risk factors hyperglycemia (glucose [Glc]), hyperinsulinemia (insulin [Ins]) and low-grade inflammation (tumor necrosis factor α [TNFα]) on the vasomotor responses of resistance arteries. Isolated small mesenteric...... arteries from 3-month-old Sprague-Dawley rats, were suspended for 21-23 h in tissue cultures containing either elevated Glc (30 mmol/l), Ins (100 nmol/l), TNFα (100 ng/ml) or combinations thereof. After incubation, the vascular response to noradrenaline (NA), phenylephrine, isoprenaline and NA...... in the presence of propranolol (10 µmol/l) was measured by wire myography. RESULTS: Arteries exposed only to combinations of the risk factors showed a significant 1.6-fold increase in the contractile NA sensitivity, which suggests that complex combinations of metabolic risk factors might lead to changes...

  3. Selectivity and Mass Transfer Limitations in Pressure-Retarded Osmosis at High Concentrations and Increased Operating Pressures.

    Science.gov (United States)

    Straub, Anthony P; Osuji, Chinedum O; Cath, Tzahi Y; Elimelech, Menachem

    2015-10-20

    Pressure-retarded osmosis (PRO) is a promising source of renewable energy when hypersaline brines and other high concentration solutions are used. However, membrane performance under conditions suitable for these solutions is poorly understood. In this work, we use a new method to characterize membranes under a variety of pressures and concentrations, including hydraulic pressures up to 48.3 bar and concentrations of up to 3 M NaCl. We find membrane selectivity decreases as the draw solution concentration is increased, with the salt permeability coefficient increasing by a factor of 2 when the draw concentration is changed from 0.6 to 3 M NaCl, even when the applied hydraulic pressure is maintained constant. Additionally, we find that significant pumping energy is required to overcome frictional pressure losses in the spacer-filled feed channel and achieve suitable mass transfer on the feed side of the membrane, especially at high operating pressures. For a meter-long module operating at 41 bar, we estimate feedwater will have to be pumped in at a pressure of at least 3 bar. Both the reduced selectivity and increased pumping energy requirements we observe in PRO will significantly diminish the obtainable net energy, highlighting important new challenges for development of systems utilizing hypersaline draw solutions.

  4. Correlation between 24-hour profile of blood pressure and ventricular arrhythmias and their prognostic significance in patients with arterial hypertension

    Directory of Open Access Journals (Sweden)

    Đorđević Dragan

    2008-01-01

    Full Text Available Background/Aim. Left ventricular hypertrophy (LVH, apart from arterial hypertension, is a risk factor for electrophysiologic heart condition disorder and sudden cardiac death. The aim of this study was to examine a relationship between complex ventricular arrhythmias and parameters of 24-hour ambulatory blood pressure monitoring in the patients with arterial hypertension and left ventricular hypertrophy (LVH, as well as their prognostic significance during a five-year follow-up. Methods. Ninety patients with arterial hypertension and LVH were included in this study (mean age 55.2±8.3 years. There were 35 healthy people in the control group (mean age 54.5±7.1 years. Left ventricular mass index was 171.9±32.4 g/m2 in the LVH group and 102.4±13.3 g/m2 in the control group. Clinical examination, echocardiogram, 24-hour ambulatory blood pressure monitoring and 24-hour holter monitoring were done in all of the examined persons. Ventricular arrhythmias were classified by the Lown classification. Results. In the LVH group there were 54 (60.0% of the patients with ≥ III Lown class. The best predictor of a Lown class were left ventricular mass index by using multivariate stepwise regression analyses (β = 0.212; p < 0.05 and small decrease of diastolic blood pressure during the night (β = -0.293; p < 0.01. The main predictor of bad prognosis was left ventricular mass index during a five year follow-up (β = 0.302; p < 0.01, for stepwise regression model: F = 8.828; p < 0.01, adjusted R2 = 0.091. Conclusion. Left ventricular arrhythmias are frequent in patients with lower decrease of blood pressure during the night. There was no correlation between the degree of ventricular arrhythmias and parameters from 24-hour blood pressure monitoring and a five-year prognosis in the patients with arterial hypertension and LVH. A bad five-year follow-up outcome of hypertensive disease depends on left ventricular mass index.

  5. Response of transonic diffuser flows to abrupt increases of back pressure: Wall pressure measurements

    Science.gov (United States)

    Bogar, T. J.; Sajben, M.

    1986-10-01

    The propagation of compression pulses in a supercritically operated transonic diffuser was investigated by use of pressure measurements along the top wall of the model. The pulses were generated at the downstream end of the diffuser by the abrupt injection of a secondary flow of air. Two types of waves were observed: (1) an upstream-traveling acoustic wave and (2) a downstream-traveling convective wave which resulted from the impingement of the acoustic wave on the shock. Wave speeds were determined for a range of diffuser pressure ratios including separated, strong-shock flows and fully attached, weak-shock flows. Streamwise distributions of initial and reflected pulse amplitudes were determined for one weak and one strong-shock case over a 3-to-1 range of initial pulse strengths.

  6. Minimal distal pressure rise after reconstructive arterial surgery in patients with multiple obstructive arteriosclerosis

    DEFF Research Database (Denmark)

    Noer, Ivan; Tønnesen, K H; Sager, P

    1980-01-01

    fifteen had ischemic ulcers. The preoperative median pressure index (per cent of arm systolic pressure) was 10% on the 1st toe. At the 10th postoperative day the median toe pressure rose to 25%. A further rise took place at the one month control to 30% which was unchanged throughout the study. All...... patients with a persistent postoperative toe pressure above 20% of arm systolic pressure were ultimately relieved from rest pain and chronic ulcers....

  7. Effect of continuous positive airway pressure treatment on pulmonary artery pressure in patients with isolated obstructive sleep apnea: a meta-analysis.

    Science.gov (United States)

    Imran, Tasnim F; Ghazipura, Marya; Liu, Spencer; Hossain, Tanzib; Ashtyani, Hormoz; Kim, Bernard; Michael Gaziano, J; Djoussé, Luc

    2016-09-01

    Pulmonary hypertension (PH) can occur in patients with obstructive sleep apnea (OSA) in the absence of cardiac or lung disease. Data on the development and severity of PH, and the effect of continuous positive airway pressure (CPAP) therapy on pulmonary artery (PA) pressures in these patients have been inconsistent in the literature. We sought to determine whether CPAP therapy affects PA pressures in patients with isolated OSA in this meta-analysis. We searched PubMed, Medline, EMBASE and other databases from January 1980 to August 2015. Studies of patients with OSA, defined as an apnea-hypopnea index >10 events/h, and PH, defined as PA pressure >25 mmHg were included. Two reviewers independently extracted data and assessed risk of bias. A total of 222 patients from seven studies (341.53 person-years) had reported PA pressures before and after treatment with CPAP therapy. 77 % of participants were men, with a mean age of 52.5 years, a mean apnea-hypopnea index of 58 events/h, and mean PA pressure of 39.3 ± 6.3 mmHg. CPAP treatment duration ranged from 3 to 70 months. Using fixed effects meta-analysis, CPAP therapy was associated with a decrease in PA pressure of 13.3 mmHg (95 % CI 12.7-14.0) in our study population. This meta-analysis found that CPAP therapy is associated with a significantly lower PA pressure in patients with isolated OSA and PH.

  8. Iron ion irradiation increases promotes adhesion of monocytic cells to arterial vascular endothelium

    Science.gov (United States)

    Kucik, Dennis; Khaled, Saman; Gupta, Kiran; Wu, Xing; Yu, Tao; Chang, Polly; Kabarowski, Janusz

    Radiation causes inflammation, and chronic, low-level vascular inflammation is a risk factor for atherosclerosis. Consistent with this, exposure to radiation from a variety of sources is associated with increased risk of heart disease and stroke. Part of the inflammatory response to radiation is a change in the adhesiveness of the endothelial cells that line the blood vessels, triggering inappropriate accumulation of leukocytes, leading to later, damaging effects of inflammation. Although some studies have been done on the effects of gamma irradiation on vascular endothelium, the response of endothelium to heavy ion radiation likely to be encountered in prolonged space flight has not been determined. We investigated how irradiation of aortic endothelial cells with iron ions affects adhesiveness of cultured aortic endothelial cells for monocytic cells and the consequences of this for development of atherosclerosis. Aortic endothelial cells were irradiated with 600 MeV iron ions at Brookhaven National Laboratory and adhesion-related changes were measured. Cells remained viable for at least 72 hours, and were even able to repair acute damage to cell junctions. We found that iron ion irradiation altered expression levels of specific endothelial cell adhesion molecules. Further, these changes had functional consequences. Using a flow chamber adhesion assay to measure adhesion of monocytic cells to endothelial cells under physiological shear stress, we found that adhesivity of vascular endothelium was enhanced in as little as 24 hours after irradiation. Further, the radiation dose dependence was not monotonic, suggesting that it was not simply the result of endothelial cell damage. We also irradiated aortic arches and carotid arteries of Apolipoprotein-E-deficient mice. Histologic analysis of these mice will be conducted to determine whether effects of radiation on endothelial adhesiveness result in consequences for development of atherosclerosis. (Supported by NSBRI

  9. Decreased adiponectin and increased inflammation expression in epicardial adipose tissue in coronary artery disease

    Directory of Open Access Journals (Sweden)

    Sun Zongquan

    2011-01-01

    Full Text Available Abstract Background Disorders of endocrine substances in epicardial adipose tissue are known causes of coronary artery disease (CAD. Adiponectin is associated with cardiovascular disease. However, expression of adiponectin in epicardial adipose tissue and its function in CAD pathogenesis is unclear. This study investigates adiponectin expression in epicardial adipose tissue in CAD patients. Methods Vessels or adipose tissue samples collected from CAD patients and non-CAD controls were examined after immunochemical staining. Adiponectin, cytokines of interleukin-6 (IL-6 and necrosis factor-α (TNF-α and toll-like receptor 4 (TLR4 expression level in adipose tissue were measured using real-time quantitative RT-PCR. Adiponectin concentrations in peripheral and coronary sinus vein plasma were measured with enzyme-linked immunosorbent assay. Peripheral vein plasma biochemistries were performed with routine laboratory techniques. Monocytes were collected from blood using lymphocyte separation medium. Expression level of cytokines and transcription factor NF-κB were measured to learn the effect of adiponectin on stearic acid-stimulated monocytes. Percentage of TLR4 positive monocytes was analyzed using flow cytometry. Results Histological examination revealed increased macrophage infiltration into epicardial adipose tissue of CAD patients. Decreased adiponectin displayed by real-time quantitative RT-PCR was associated with enhanced cytokines of IL-6 and TNF-α or TLR4 expression level in epicardial adipose tissue, suggesting decreased circulating adiponectin may be useful as a more sensitive predictor for coronary atherosclerosis than routine laboratory examinations. Adiponectin suppressed secretion of IL-6 and TNF-α in stimulated monocytes and TLR4 was expressed on cell surfaces. Conclusions Endocrine disorders in epicardial adipose tissue are strongly linked to CAD, and adiponectin has a protective effect by inhibiting macrophage

  10. Modelling of the dynamic relationship between arterial pressure, renal sympathetic nerve activity and renal blood flow in conscious rabbits.

    Science.gov (United States)

    Berger, C S; Malpas, S C

    1998-12-01

    A linear autoregressive/moving-average model was developed to describe the dynamic relationship between mean arterial pressure (MAP), renal sympathetic nerve activity (SNA) and renal blood flow (RBF) in conscious rabbits. The RBF and SNA to the same kidney were measured under resting conditions in a group of eight rabbits. Spectral analysis of the data sampled at 0.4 Hz showed that the low-pass bandwidth of the signal power for RBF was approximately 0. 05 Hz. An autoregressive/moving-average model with an exogenous input (ARMAX) was then derived (using the iterative Gauss-Newton algorithm provided by the MATLAB identification Toolbox), with MAP and SNA as inputs and RBF as output, to model the low-frequency fluctuations. The model step responses of RBF to changes in SNA and arterial pressure indicated an overdamped response with a settling time that was usually less than 2 s. Calculated residuals from the model indicated that 79 5 % (mean s.d., averaged over eight independent experiments) of the variation in RBF could be accounted for by the variations in arterial pressure and SNA. Two additional single-input models for each of the inputs were similarly obtained and showed conclusively that changes in RBF, in the conscious resting rabbit, are a function of both SNA and MAP and that the SNA signal has the predominant effect. These results indicate a strong reliance on SNA for the dynamic regulation of RBF. Such information is likely to be important in understanding the diminished renal function that occurs in a variety of disease conditions in which overactivity of the sympathetic nervous system occurs.

  11. Increased prevalence of coronary artery disease risk markers in patients with chronic hepatitis C

    DEFF Research Database (Denmark)

    Roed, Torsten; Kristoffersen, Ulrik Sloth; Knudsen, Andreas

    2014-01-01

    % confidence interval [CI] 0.9-2.7) and smoked more (53% versus 38%, PR 1.4; 95% CI 0.9-2.1). The two groups had similar body mass index (mean 25.0 versus 25.7 kg/m(2)), whereas those with chronic hepatitis C had less dyslipidemia (including significantly lower low-density lipoprotein and cholesterol...... of several coronary artery disease risk markers. These results may be important when evaluating the appropriateness of screening for coronary artery disease and its risk factors in chronic hepatitis C....

  12. L-Cysteine and L-AP4 microinjections in the rat caudal ventrolateral medulla decrease arterial blood pressure.

    Science.gov (United States)

    Takemoto, Yumi

    2014-12-01

    The thiol amino acid L-cysteine increases arterial blood pressure (ABP) when injected into the cerebrospinal fluid space in conscious rats, indicating a pressor response to centrally acting L-cysteine. A prior synaptic membrane binding assay suggests that L-cysteine has a strong affinity for the L-2-amino-4-phosphonobutyric acid (L-AP4) binding site. The central action of L-cysteine may be vial-AP4 sensitive receptors. The present study investigated cardiovascular responses to L-cysteine and L-ap4 microinjected into the autonomic area of the caudal ventrolateral medulla (CVLM) where inhibitory neurons regulate ABP via pre-sympathetic vasomotor neurons. Both the injection of L-cysteine and L-AP4 in the CVLM sites identified with L-glutamate produced the same depressor and bradycardic responses in urethane-anesthetized rats. Neither a prior antagonist microinjection of MK801 for the N-methyl-D-aspartate (NMDA) receptor nor CNQX for the non-NMDA receptor attenuated the responses to L-cysteine, but the combination of the two receptor blocking with an additional prior injection abolished the response. In contrast, either receptor blockade alone abolished the response to L-AP4, indicating distinct mechanisms between responses to L-cysteine and L-AP4 in the CVLM. The results indicate that the CVLM is a central active site for L-cysteine's cardiovascular response. Central L-cysteine's action could be independent of the L-AP4 sensitive receptors. Cardiovascular regulation may involve endogenous L-cysteine in the CVLM. Further multidisciplinary examinations are required to elaborate on L-cysteine's functional roles in the CVLM.

  13. Quadratic function between arterial partial oxygen pressure and mortality risk in sepsis patients: an interaction with simplified acute physiology score

    OpenAIRE

    Zhongheng Zhang; Xuqing Ji

    2016-01-01

    Oxygen therapy is widely used in emergency and critical care settings, while there is little evidence on its real therapeutic effect. The study aimed to explore the impact of arterial oxygen partial pressure (PaO2) on clinical outcomes in patients with sepsis. A large clinical database was employed for the study. Subjects meeting the diagnostic criteria of sepsis were eligible for the study. All measurements of PaO2 were extracted. The primary endpoint was death from any causes during hospita...

  14. Age, hypertension and arterial function.

    Science.gov (United States)

    McEniery, Carmel M; Wilkinson, Ian B; Avolio, Albert P

    2007-07-01

    1. Ageing exerts a marked effect on the cardiovascular system and, in particular, the large arteries. Using a variety of techniques to assess arterial stiffness, many cross-sectional studies have demonstrated a significant relationship between age and aortic stiffness, although the age-related changes observed in peripheral arteries appear to be less marked. 2. The relationship between arterial stiffness and hypertension is more complex. The distending, or mean arterial, pressure is an important confounder of measurements of arterial stiffness and, therefore, must be taken into consideration when assessing arterial stiffness in hypertensive subjects or investigating the effect of antihypertensive agents. Current methods for correcting for differences in distending pressure involve pharmacological manipulation, statistical correction or mathematical manipulation of stiffness indices. 3. Many studies have provided evidence that both peripheral (muscular) and central (elastic) arteries are stiffer in subjects with mixed (systolic/diastolic) hypertension compared with normotensive subjects. However, it is unclear to what extent differences in mean arterial pressure explain the observed differences in hypertensive subjects. In contrast, isolated systolic hypertension is associated with increased aortic, but not peripheral artery, stiffness, although the underlying mechanisms are somewhat unclear. 4. Traditional antihypertensive agents appear to reduce arterial stiffness, but mostly via an indirect effect of lowering mean pressure. Therefore, therapies that target the large arteries to reduce stiffness directly are urgently required. Agents such as nitric oxide donors and phosphodiesterase inhibitors may be useful in reducing stiffness via functional mechanisms. In addition, inhibitors or breakers of advanced glycation end-product cross-links between proteins, such as collagen and elastin, hold substantial promise.

  15. An acoustical pump capable of significantly increasing pressure ratio of thermoacoustic heat engines

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Pressure ratio is one of the important parameters for evaluating a thermoacoustic heat engine. A so-called acoustical pump, which is capable of significantly increasing pressure ratio of a thermoacoustic heat engine, is proposed. Its operating principle is given. Also, a verification experiment is done with nitrogen gas in the energy-focused thermoacoustic heat engine, showing that the pressure ratio increased from 1.25 to 1.47.

  16. Effect of stellate block on vasomotor factor, vascular endothelial nitricoxide synthase and pulmonary arterial pressure in rabbits with hypoxic pulmonary artery hypertension

    Institute of Scientific and Technical Information of China (English)

    Shunhou He; Qing Li; Sen Chen; Qingxiu Wang

    2007-01-01

    BACKGROUND: At present, inhalation of nitrogen monoxidum (NO) or other angiotenic is widely used to cure hypoxic pulmonary artery hypertension. In addition, recent researches demonstrate that postganglionic fiber of stellate ganglion can regulate contents of blood vessel endothelium-calcitonin gene-related peptide (BE-CGRP) and nitricoxide synthase (NOS) in lung tissue. Therefore, stellate ganglion which is blocked with the local anesthetic may cause therapeutic effects on hypoxic pulmonary artery hypertension.OBJECTIVE: To observe the effects of stellate block on calcitonin gene-related peptide (CGRP) of vasodilation factors, prostacyclin, endothelin-1 of vasoconstriction factors, thromboxan, blood vessel endothelium-nitricoxide synthase (BE-NOS) and mean arterial pressure of lung tissue in rabbits with hypoxic pulmonary artery hypertension.DESIGN: Randomly controlled animal study.SETTING: Neurological Institute of Taihe Hospital Affiliated to Yunyang Medical College.MATERIALS: A total of 24 adult Japanese rabbits of both genders and weighing 2.3 - 2.6 kg were provided by Animal Experimental Center of Hubei Academy of Medical Science. SP kit was provided by Beijing Zhongshan Biotechnology Co., Ltd.; moreover, kits of endothelin-1, CGRP, prostacyclin and thromboxan were provided by Radioimmunity Institute, Scientific and Technological Developing Center, General Hospital of Chinese PLA, and color image analytical system (Leica-Q500IW) was made in Germany.METHODS: The experiment was carried out in the Neurological Institute of Taihe Hospital affiliated to Yunyang Medical College from February to December 2002, ① Rabbits were performed with aseptic manipulation to exposure left stellate ganglion and then it was put in epidural catheter for 1 week. In addition,one end of epidural catheter was fixed near by stellate ganglion and the other end was fixed through dorsal neck. All rabbits were randomly divided into 4 groups, including normal control group, stellate block

  17. Increased anandamide induced relaxation in mesenteric arteries of cirrhotic rats: role of cannabinoid and vanilloid receptors

    Science.gov (United States)

    Domenicali, M; Ros, J; Fernández-Varo, G; Cejudo-Martín, P; Crespo, M; Morales-Ruiz, M; Briones, A M; Campistol, J-M; Arroyo, V; Vila, E; Rodés, J; Jiménez, W

    2005-01-01

    Background and aims: Anandamide is an endocannabinoid that evokes hypotension by interaction with peripheral cannabinoid CB1 receptors and with the perivascular transient receptor potential vanilloid type 1 protein (TRPV1). As anandamide has been implicated in the vasodilated state in advanced cirrhosis, the study investigated whether the mesenteric bed from cirrhotic rats has an altered and selective vasodilator response to anandamide. Methods: We assessed vascular sensitivity to anandamide, mRNA and protein expression of cannabinoid CB1 receptor and TRPV1 receptor, and the topographical distribution of cannabinoid CB1 receptors in resistance mesenteric arteries of cirrhotic and control rats. Results: Mesenteric vessels of cirrhotic animals displayed greater sensitivity to anandamide than control vessels. This vasodilator response was reverted by CB1 or TRPV1 receptor blockade, but not after endothelium denudation or nitric oxide inhibition. Anandamide had no effect on distal femoral arteries. CB1 and TRPV1 receptor protein was higher in cirrhotic than in control vessels. Neither CB1 mRNA nor protein was detected in femoral arteries. Immunochemistry showed that CB1 receptors were mainly in the adventitia and in the endothelial monolayer, with higher expression observed in vessels of cirrhotic rats than in controls. Conclusions: These results indicate that anandamide is a selective splanchnic vasodilator in cirrhosis which predominantly acts via interaction with two different types of receptors, CB1 and TRPV1 receptors, which are mainly located in perivascular sensory nerve terminals of the mesenteric resistance arteries of these animals. PMID:15753538

  18. Calcium intake is not associated with increased coronary artery calcification: The Framingham Study

    Science.gov (United States)

    Adequate calcium intake is known to protect the skeleton. However, studies that have reported adverse effects of calcium supplementation on vascular events have raised widespread concern. We assessed the association between calcium intake (from diet and supplements) and coronary artery calcification...

  19. Increased levels of endothelin ETB receptor mRNA in human omental arteries after organ culture

    DEFF Research Database (Denmark)

    Möller, S; Adner, M; Edvinsson, L

    1998-01-01

    1. Using competitive reverse transcription-polymerase chain reaction (RT-PCR) and in vitro pharmacology, smooth muscle endothelin ETB receptor expression was studied in segments of human omental artery, fresh and after organ culture for 1 and 5 days. 2. The competitive RT-PCR assay used in the pr...

  20. Increased alphaCGRP potency and CGRP-receptor antagonist affinity in isolated hypoxic porcine intramyocardial arteries

    DEFF Research Database (Denmark)

    Hasbak, Philip; Eskesen, Karen; Schifter, Søren

    2005-01-01

    receptor mRNA. 6. We conclude that hypoxic incubation increases the relaxation and cAMP production induced by alphaCGRP and AMY in rings of porcine coronary arteries in vitro. A concomitant release of adenosine, a cyclooxygenase product, an endothelium-derived substance, activation of vascular ATP...... effect in hypoxia. The Schild plot-derived pK(B) values revealed an increase in the apparent affinity of the antagonist for the CGRP(1) receptor from 7.0 to 7.2 under control conditions versus 8.0 in hypoxia. 5. Removal of endothelium, peptidase inhibitors, preincubation with the adenosine A(2A) receptor......1. This study describes the effects of hypoxia on relaxing responses and cAMP production induced by the known vasodilator peptides: alphaCGRP, amylin (AMY) and adrenomedullin (AM) on isolated pig coronary arteries in vitro. 2. Hypoxic incubation increased the vasorelaxant effect of alphaCGRP (four...

  1. 杀菌性/通透性增加蛋白模拟肽对内毒素休克模型家兔动脉血压影响的研究%Effects of bactericidal/permeability increasing protein modeling peptide on arterial blood pressure of endotoxin-shocked rabbits

    Institute of Scientific and Technical Information of China (English)

    卫国; 吕根法; 郭毅斌; 郑江

    2003-01-01

    杀菌性/通透性增加蛋白(Bactericidal/permeability increasing protein,BPI)是一种存在于人及哺乳动物中性粒细胞嗜天青颗粒中带正电荷的蛋白质,具有较强的杀灭革兰阴性菌(Gramnegative bacteria,GNB)及中和内毒素(Lipopolysaeeharide,LPS)的能力,对严重GNB感染具有一定疗效。通过多年的研究,本室采用计算机分子模拟技术设计合成了BP1模拟肽,本研究拟通过观察BP1模拟肽对平均动脉压、脉压的影响,以了解其抗内毒素休克功效。

  2. Fatores de risco associados à pressão arterial elevada em adolescentes Risk factors associated with high blood pressure in adolescents

    Directory of Open Access Journals (Sweden)

    Kelly Samara da Silva

    2007-08-01

    = 5.5; CI 95% = 1.11-27.53, and girls: OR = 4.8; CI 95% = 1.51-15.45. The other variables did not seem to be associated with high AP. In this study, among the various risk factors analyzed, body overweight acted out as the only potential risk factor increasing arterial blood pressure in adolescents, irrespective of their sex and age.

  3. The effect of siesta in parameters of cardiac structure and in interpretation of ambulatory arterial blood pressure monitoring

    Directory of Open Access Journals (Sweden)

    Marco A.M. Gomes

    2000-04-01

    Full Text Available OBJECTIVE: To evaluate the influence of the siesta in ambulatory blood pressure (BP monitoring and in cardiac structure parameters. METHODS: 1940 ambulatory arterial blood pressure monitoring tests were analyzed (Spacelabs 90207, 15/15 minutes from 7:00 to 22:00 hours and 20/20 minutes from 22:01 to 6.59hours and 21% of the records indicated that the person had taken a siesta (263 woman, 52±14 years. The average duration of the siesta was 118±58 minutes. RESULTS: (average ± standard deviation The average of systolic/diastolic pressures during wakefulness, including the napping period, was less than the average for the period not including the siesta (138±16/85±11 vs 139±16/86±11 mmHg, p5%. CONCLUSION: The siesta influenced the heart structure parameters and from a statistical point of view the average of systolic and diastolic pressures and the respective pressure loads of the wakeful period.

  4. Contribution of pH, diprotonated phosphate and potassium for the reflex increase in blood pressure during handgrip

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Madsen, P; Nielsen, H B

    1998-01-01

    The relative importance of pH, diprotonated phosphate (H2PO4-) and potassium (K+) for the reflex increase in mean arterial pressure (MAP) during exercise was evaluated in seven subjects during rhythmic handgrip at 15 and 30% maximal voluntary contraction (MVC), followed by post-exercise muscle...... ischaemia (PEMI). During 15% MVC, MAP rose from 92 +/- 1 to 103 +/- 2 mmHg, [K+] from 4.1 +/- 0.1 to 5.1 +/- 0.1 mmol L-1, while the intracellular (7.00 +/- 0.01 to 6.80 +/- 0.06) and venous pH fell (7.39 +/- 0.01 to 7.30 +/- 0.01) (P ... and the venous [H2PO4-] from 0.14 +/- 0.01 to 0.16 +/- 0.01 mmol L-1 (P MVC handgrip, MAP rose to 130 +/- 3 mm...

  5. Endotracheal tube cuff pressure increases significantly during anterior cervical fusion with the Caspar instrumentation system.

    Science.gov (United States)

    Sperry, R J; Johnson, J O; Apfelbaum, R I

    1993-06-01

    To determine whether endotracheal tube cuff pressure increases significantly with surgical retraction and cervical spine distraction during anterior cervical spine surgery with Caspar instrumentation, we prospectively studied 10 patients undergoing this procedure. The tracheas of all patients were intubated with a Mallinckrodt Hi-Lo endotracheal tube. Tracheal tube cuff pressures measured with a transducer system were 42.4 mm Hg +/- 7.0 mm Hg (SEM) after intubation and cuff inflation. Air was removed from the endotracheal tube cuff until the trachea was just barely sealed at a cuff pressure of 15.2 mm Hg +/- 1.6 mm Hg. The endotracheal tube cuff pressure was readjusted to "just-seal" pressure before the surgeons introduced the Caspar instrumentation. The cuff pressure with traction and distraction was 43.2 mm Hg +/- 5.0 mm Hg. This pressure was significantly increased from the "just-seal" pressure, and from the cuff pressure after instrumentation was discontinued (9.8 mm Hg +/- 2.3 mm Hg). We conclude that anterior cervical spine surgery with Caspar instrumentation is associated with a significant increase in endotracheal tube cuff pressure.

  6. Has blood pressure increased in children in response to the obesity epidemic?

    Science.gov (United States)

    Chiolero, Arnaud; Bovet, Pascal; Paradis, Gilles; Paccaud, Fred

    2007-03-01

    The associations between elevated blood pressure and overweight, on one hand, and the increasing prevalence over time of pediatric overweight, on the other hand, suggest that the prevalence of elevated blood pressure could have increased in children over the last few decades. In this article we review the epidemiologic evidence available on the prevalence of elevated blood pressure in children and trends over time. On the basis of the few large population-based surveys available, the prevalence of elevated blood pressure is fairly high in several populations, whereas there is little direct evidence that blood pressure has increased during the past few decades despite the concomitant epidemic of pediatric overweight. However, a definite conclusion cannot be drawn yet because of the paucity of epidemiologic studies that have assessed blood pressure trends in the same populations and the lack of standardized methods used for the measurement of blood pressure and the definition of elevated blood pressure in children. Additional studies should examine if favorable secular trends in other determinants of blood pressure (eg, dietary factors, birth weight, etc) may have attenuated the apparently limited impact of the epidemic of overweight on blood pressure in children.

  7. Benidipine has effects similar to losartan on the central blood pressure and arterial stiffness in mild to moderate essential hypertension

    Institute of Scientific and Technical Information of China (English)

    Sang-Hyun Ihm; Hui-Kyung Jeon; Shung Chull Chae; Do-Sun Lim; Kee-Sik Kim; Dong-Ju Choi; Jong-Won Ha

    2013-01-01

    Background Central blood pressure (BP) is pathophysiologically more important than peripheral BP for the pathogenesis of cardiovascular disease.Arterial stiffness is also a good predictor of cardiovascular morbidity and mortality.The effects of benidipine,a unique dual L-/T-type calcium channel blocker,on central BP have not been reported.This study aimed to compare the effect of benidipine and losartan on the central BP and arterial stiffness in mild to moderate essential hypertensives.Methods This 24 weeks,multi-center,open label,randomized,active drug comparative,parallel group study was designed as a non-inferiority study.The eligible patients (n=200) were randomly assigned to receive benidipine (n=101)or losartan (n=99).Radial artery applanation tonometry and pulse wave analysis were used to measure the central BP,pulse wave velocity (PWV) and augmentation index (Alx).We also measured the metabolic and inflammatory markers.Results After 24 weeks,the central BP decreased significantly from baseline by (16.8+14.0/10.5+9.2) mmHg (1mmHg =0.133 kPa) (systolic/diastolic BP; P <0.001) in benidipine group and (18.9+14.7/12.1+10.2) mmHg (P <0.001)in losartan group respectively.Both benidipine and losartan groups significantly lowered peripheral BP (P <0.001) and Alx (P <0.05),but there were no significant differences between the two groups.The mean aortic,brachial and femoral PWV did not change in both groups after 24-week treatment.There were no significant changes of the blood metabolic and inflammatory biomarkers in each group.Conclusion Benidipine is as effective as losartan in lowering the central and peripheral BP,and improving arterial stiffness.

  8. Positive association between increased popliteal artery vessel wall thickness and generalized osteoarthritis: is OA also part of the metabolic syndrome?

    Energy Technology Data Exchange (ETDEWEB)

    Kornaat, Peter R.; Sharma, Ruby; Geest, Rob J. van der; Lamb, Hildo J.; Bloem, Johan L.; Watt, Iain [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Kloppenburg, Margreet [Leiden University Medical Center, Department of Rheumatology, Leiden (Netherlands); Hellio le Graverand, Marie-Pierre [Pfizer Global Research and Development, New London, CT (United States)

    2009-12-15

    The purpose of the study was to determine if a positive association exists between arterial vessel wall thickness and generalized osteoarthritis (OA). Our hypothesis is that generalized OA is another facet of the metabolic syndrome. The medical ethical review board of our institution approved the study. Written informed consent was obtained from each patient prior to the study. Magnetic resonance (MR) images of the knee were obtained in 42 patients who had been diagnosed with generalized OA at multiple joint sites. Another 27 MR images of the knee were obtained from a matched normal (non-OA) reference population. Vessel wall thickness of the popliteal artery was quantitatively measured by dedicated software. Linear regression models were used to investigate the association between vessel wall thickness and generalized OA. Adjustments were made for age, sex, and body mass index (BMI). Confidence intervals (CI) were computed at the 95% level and a significance level of {alpha} = 0.05 was used. Patients in the generalized OA population had a significant higher average vessel wall thickness than persons from the normal reference population (p {<=} {alpha}), even when correction was made for sex, age, and BMI. The average vessel wall thickness of the popliteal artery was 1.09 mm in patients with generalized OA, and 0.96 mm in the matched normal reference population. The association found between increased popliteal artery vessel wall thickness and generalized osteoarthritis suggests that generalized OA might be another facet of the metabolic syndrome. (orig.)

  9. Increased regional epicardial fat volume associated with reversible myocardial ischemia in patients with suspected coronary artery disease.

    Science.gov (United States)

    Khawaja, Tuba; Greer, Christine; Thadani, Samir R; Kato, Tomoko S; Bhatia, Ketan; Shimbo, Daichi; Kontak, Andrew; Konkak, Andrew; Bokhari, Sabahat; Einstein, Andrew J; Schulze, P Christian

    2015-04-01

    Epicardial adipose tissue is a source of pro-inflammatory cytokines and has been linked to the development of coronary artery disease. No study has systematically assessed the relationship between local epicardial fat volume (EFV) and myocardial perfusion defects. We analyzed EFV in patients undergoing SPECT myocardial perfusion imaging combined with computed tomography (CT) for attenuation correction. Low-dose CT without contrast was performed in 396 consecutive patients undergoing SPECT imaging for evaluation of coronary artery disease. Regional thickness, cross-sectional areas, and total EFV were assessed. 295 patients had normal myocardial perfusion scans and 101 had abnormal perfusion scans. Mean EFVs in normal, ischemic, and infarcted hearts were 99.8 ± 82.3 cm(3), 156.4 ± 121.9 cm(3), and 96.3 ± 102.1 cm(3), respectively (P coronary artery (87.1 ± 76.4 vs 46.7 ± 40.6 cm(3); P = 0.005). Our results demonstrate increased regional epicardial fat in patients with active myocardial ischemia compared to patients with myocardial scar or normal perfusion on nuclear perfusion scans. Our results suggest a potential role for cardiac CT to improve risk stratification in patients with suspected coronary artery disease.

  10. Quantitative 3D pulmonary MR-perfusion in patients with pulmonary arterial hypertension: Correlation with invasive pressure measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ley, Sebastian [Department of Pediatric Radiology, Children' s Hospital University Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg (Germany) and Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)]. E-mail: ley@gmx.net; Mereles, Derliz [Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Risse, Frank [Medical Physics in Radiology (E020), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Gruenig, Ekkehard [Internal Medicine III, University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg (Germany); Ley-Zaporozhan, Julia [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Tecer, Zueleyha [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Puderbach, Michael [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Fink, Christian [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Department of Clinical Radiology, University Medical Center Grosshadern, Ludwigs-Maximilians-University, Munich (Germany); Kauczor, Hans-Ulrich [Department of Radiology (E010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)

    2007-02-15

    Purpose: Pathological changes of the peripheral pulmonary arteries induce pulmonary arterial hypertension (PAH). Aim of this study was to quantitatively assess the effect of PAH on pulmonary perfusion by 3D-MR-perfusion techniques and to compare findings to healthy controls. Furthermore, quantitative perfusion data were correlated with invasive pressure measurements. Material and methods: Five volunteers and 20 PAH patients (WHO class II or III) were examined using a 1.5 T MR scanner. Measurement of pulmonary perfusion was done in an inspiratory breathhold (FLASH3D; 3.5 mm x 1.9 mm x 4 mm; TA per 3D dataset 1.5 s). Injection of contrast media (0.1 mmol Gd-DTPA/kg BW) and image acquisition were started simultaneously. Evaluation of 3D perfusion was done using singular value decomposition. Lung borders were outlined manually. Each lung volume was divided into three regions (anterior, middle, posterior), and the following parameters were assessed: Time-to-Peak (TTP), blood flow (PBF), blood volume (PBV), and mean transit time (MTT). In 10 patients invasive pulmonary artery pressure measurements were available and correlated to the perfusion measurements. Results: In both, controls and patients, an anterior-to-posterior gradient with higher PBF and PBV posterior was observed. In the posterior lung region, a significant difference (p < 0.05) was found for TTP (12 s versus 16 s) and MTT (4 s versus 6 s) between volunteers and patients. PBF and PBV were lower in patients than in volunteers (i.e. dorsal regions: 124 versus 180 ml/100 ml/min and 10 versus 12 ml/100 ml), but the difference failed to be significant. The ratio of PBF and PBV between the posterior and the middle or ventral regions showed no difference between both groups. A moderate linear correlation between mean pulmonary arterial pressure (mPAP) and PBV (r = 0.51) and MTT (r = 0.56) was found. Conclusion: The only measurable effect of PAH on pulmonary perfusion is a prolonging of the MTT. There is only a

  11. A computational analysis of the long-term regulation of arterial pressure [v2; ref status: indexed, http://f1000r.es/2hm

    Directory of Open Access Journals (Sweden)

    Daniel A. Beard

    2013-12-01

    Full Text Available The asserted dominant role of the kidneys in the chronic regulation of blood pressure and in the etiology of hypertension has been debated since the 1970s. At the center of the theory is the observation that the acute relationships between arterial pressure and urine production—the acute pressure-diuresis and pressure-natriuresis curves—physiologically adapt to perturbations in pressure and/or changes in the rate of salt and volume intake. These adaptations, modulated by various interacting neurohumoral mechanisms, result in chronic relationships between water and salt excretion and pressure that are much steeper than the acute relationships. While the view that renal function is the dominant controller of arterial pressure has been supported by computer models of the cardiovascular system known as the “Guyton-Coleman model”, no unambiguous description of a computer model capturing chronic adaptation of acute renal function in blood pressure control has been presented. Here, such a model is developed with the goals of: 1. representing the relevant mechanisms in an identifiable mathematical model; 2. identifying model parameters using appropriate data; 3. validating model predictions in comparison to data; and 4. probing hypotheses regarding the long-term control of arterial pressure and the etiology of primary hypertension. The developed model reveals: long-term control of arterial blood pressure is primarily through the baroreflex arc and the renin-angiotensin system; and arterial stiffening provides a sufficient explanation for the etiology of primary hypertension associated with ageing. Furthermore, the model provides the first consistent explanation of the physiological response to chronic stimulation of the baroreflex.

  12. A computational analysis of the long-term regulation of arterial pressure [v1; ref status: indexed, http://f1000r.es/1xq

    Directory of Open Access Journals (Sweden)

    Daniel A. Beard

    2013-10-01

    Full Text Available The asserted dominant role of the kidneys in the chronic regulation of blood pressure and in the etiology of hypertension has been debated since the 1970s. At the center of the theory is the observation that the acute relationships between arterial pressure and urine production—the acute pressure-diuresis and pressure-natriuresis curves—physiologically adapt to perturbations in pressure and/or changes in the rate of salt and volume intake. These adaptations, modulated by various interacting neurohumoral mechanisms, result in chronic relationships between water and salt excretion and pressure that are much steeper than the acute relationships. While the view that renal function is the dominant controller of arterial pressure has been supported by computer models of the cardiovascular system known as the “Guyton-Coleman model”, no unambiguous description of a computer model capturing chronic adaptation of acute renal function in blood pressure control has been presented. Here, such a model is developed with the goals of: 1. capturing the relevant mechanisms in an identifiable mathematical model; 2. identifying model parameters using appropriate data; 3. validating model predictions in comparison to data; and 4. probing hypotheses regarding the long-term control of arterial pressure and the etiology of primary hypertension. The developed model reveals: long-term control of arterial blood pressure is primarily through the baroreflex arc and the renin-angiotensin system; and arterial stiffening provides a sufficient explanation for the etiology of primary hypertension associated with ageing. Furthermore, the model provides the first consistent explanation of the physiological response to chronic stimulation of the baroreflex.

  13. Clinical and psychological characteristics of patients with arterial hypertension, consuming an increased amount of salt

    OpenAIRE

    O. B. Poselyugina

    2015-01-01

    Objective: to Study the potential development of links between the formation of neurotic disorders personality and high salt intake (S) with food in patients with arterial hypertension (AH).Materials and methods: the study involved 229 patients with essential hypertension. We determined the threshold of taste sensitivity to salt (TTS), the daily excretion of sodium ions in urine, was assessed psychological status of the patients, the type of attitude to the disease (LOBI), the severity of dep...

  14. Growth and β-galactosidase activity in cultures of Kluyveromyces marxianus under increased air pressure

    OpenAIRE

    2003-01-01

    Aims: To investigate the effect of total air pressure raise on cell growth and intracellular β-galactosidase activity in batch cultures of Kluyveromyces marxianus CBS 7894. Methods and Results: A pressurized bioreactor was used for K. marxianus batch cultivation under increased air pressure from 1.2 to 6 bar. Under these conditions no inhibition of cell growth was observed. Moreover, the improvement of the oxygen transfer rate (OTR) from the gas to the culture medium by pressuriza...

  15. Excess pressure integral predicts cardiovascular events independent of other risk factors in the conduit artery functional evaluation substudy of Anglo-Scandinavian Cardiac Outcomes Trial.

    Science.gov (United States)

    Davies, Justin E; Lacy, Peter; Tillin, Therese; Collier, David; Cruickshank, J Kennedy; Francis, Darrel P; Malaweera, Anura; Mayet, Jamil; Stanton, Alice; Williams, Bryan; Parker, Kim H; McG Thom, Simon A; Hughes, Alun D

    2014-07-01

    Excess pressure integral (XSPI), a new index of surplus work performed by the left ventricle, can be calculated from blood pressure waveforms and may indicate circulatory dysfunction. We investigated whether XSPI predicted future cardiovascular events and target organ damage in treated hypertensive individuals. Radial blood pressure waveforms were acquired by tonometry in 2069 individuals (aged, 63±8 years) in the Conduit Artery Functional Evaluation (CAFE) substudy of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT). Measurements of left ventricular mass index (n=862) and common carotid artery intima media thickness (n=923) were also performed. XSPI and the integral of reservoir pressure were lower in people treated with amlodipine±perindopril than in those treated with atenolol±bendroflumethiazide, although brachial systolic blood pressure was similar. A total of 134 cardiovascular events accrued during a median 3.4 years of follow-up; XSPI was a significant predictor of cardiovascular events after adjustment for age and sex, and this relationship was unaffected by adjustment for conventional cardiovascular risk factors or Framingham risk score. XSPI, central systolic blood pressure, central augmentation pressure, central pulse pressure, and integral of reservoir pressure were correlated with left ventricular mass index, but only XSPI, augmentation pressure, and central pulse pressure were associated positively with carotid artery intima media thickness. Associations between left ventricular mass index, XSPI, and integral of reservoir pressure and carotid artery intima media thickness and XSPI were unaffected by multivariable adjustment for other covariates. XSPI is a novel indicator of cardiovascular dysfunction and independently predicts cardiovascular events and targets organ damage in a prospective clinical trial.

  16. Vital Signs – Presión arterial alta (High Blood Pressure)

    Centers for Disease Control (CDC) Podcasts

    2012-10-02

    En los EE. UU. casi un tercio de la población adulta tiene presión arterial alta, el principal factor de riesgo de enfermedades cardiacas y accidentes cerebrovasculares, dos de las principales causas de muerte en el país.  Created: 10/2/2012 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 10/17/2012.

  17. High-circulating leptin levels are associated with increased blood pressure in uncontrolled resistant hypertension.

    Science.gov (United States)

    de Haro Moraes, C; Figueiredo, V N; de Faria, A P C; Barbaro, N R; Sabbatini, A R; Quinaglia, T; Ferreira-Melo, S E; Martins, L C; Demacq, C; Júnior, H M

    2013-04-01

    Leptin and aldosterone have been associated with the pathophysiological mechanisms of hypertension. However, despite studies showing the association of leptin with intima-media thickness, arterial distensibility and sympathetic nerve activation, the relationship between leptin and blood pressure (BP) in resistant hypertension (RHTN) is unknown. We aimed to assess the correlation of plasma leptin and aldosterone levels with BP in uncontrolled controlled RHTN (UCRHTN) and CRHTN patients. Plasma leptin and aldosterone levels, office BP, ambulatory BP monitoring and heart rate were measured in 41 UCRHTN, 39 CRHTN and 31 well-controlled HTN patients. No differences were observed between the three groups regarding gender, body mass index and age. The UCRHTN group had increased leptin when compared with CRHTN and well-controlled HTN patients (38.2±21.4, 19.6±8.7 and 20.94±13.9 ng ml(-1), respectively; P<0.05). Aldosterone levels values were also statistically different when comparing RHTN, CRHTN and well-controlled HTN patients (9.6±3.8, 8.1±5.0 and 8.0±4.7 ng dl(-1), respectively; P<0.05). As expected, UCRHTN patients had higher heart rate values compared with CRHTN and well-controlled HTN patients (86.2±7.2, 83.5±6.7 and 83.4±8.5, respectively; P<0.05). Plasma leptin positively correlated with systolic (SBP) and diastolic BP (DBP), and aldosterone (r=0.43, 0.35 and 0.47, respectively; all P<0.05) in UCRHTN, but neither in the CRHTN nor in the HTN group. Simple linear regression showed that SBP, DBP and aldosterone may be predicted by leptin (r(2)=0.16, 0.15 and 0.19, respectively; all P<0.05) only in the UCRHTN subgroup. In conclusion, UCRHTN patients have higher circulating leptin levels associated with increased plasma aldosterone and BP levels when compared with CRHTN and HTN subjects.

  18. Oxygen tension and normalisation pressure modulate nifedipine-sensitive relaxation of human placental chorionic plate arteries.

    Science.gov (United States)

    Cooper, E J; Wareing, M; Greenwood, S L; Baker, P N

    2006-01-01

    Fetoplacental blood vessel constriction in response to reduced oxygenation has been demonstrated in placenta perfused in vitro. In pulmonary vessels, hypoxic vasoconstriction involves Ca2+ influx into smooth muscle through membrane ion channels including voltage-gated Ca2+ channels (VGCCs). We hypothesised that VGCCs are involved in agonist-induced constriction of fetoplacental resistance vessels and that their contribution is modulated by oxygen. Chorionic plate small arteries were studied using wire myography. Arteries were normalised at high (0.9 of L(13.3 kPa)) or low (0.9 of L(5.1 kPa)) stretch and experiments performed at 156, 38 or 15 mmHg oxygen. At low stretch, U46619 (thromboxane-mimetic) or KCl (smooth muscle depolarisation) constriction was greater at 38 than 156 or 15 mmHg oxygen. An L-type VGCC blocker nifedipine, inhibited KCl constriction by >85% but was less effective in U46619 constrictions (43-67%). At high stretch, nifedipine inhibition of KCl- and U46619-induced constriction was less at 15 than 38 or 156 mmHg oxygen. Oxygen did not affect constriction to U46619 or nifedipine-induced relaxation when vessels were normalised at high stretch. In conclusion, oxygen modulates chorionic plate arterial constriction at low stretch but regulation is lost at high stretch. U46619 constriction is underlain by VGCCs and nifedipine-insensitive processes; their relative contribution is influenced by oxygen.

  19. Skin perfusion pressure measured by isotope washout in legs with arterial occlusive disease. Evaluation of different tracers, comparison to segmental systolic pressure, angiography and transcutaneous oxygen tension and variations during changes in systemic blood pressure

    DEFF Research Database (Denmark)

    Holstein, P; Trap-Jensen, J; Bagger, H;

    1983-01-01

    digit (strain gauge technique). The two different methods correlated statistically significant at all four levels, but the systolic blood pressures were higher than the SPP in particular in diabetic legs; (3) Angiograms in 35 legs with AOD showed that the SPP on the ankle was only consistently decreased......The skin perfusion pressure (SPP) measured as the isotope washout cessation external pressure is valuable in selection of major amputation level. Five methodological investigations important to clinical use were carried out: (1) In five normal legs and 10 legs with arterial occlusive disease (AOD......Hg (range 18-98) (P less than 0.02). The average washout constant for the three different tracers were approximately equal and correlated statistically significant with the SPP; (2) In 59 legs with AOD, segmental SPP was compared to segmental systolic blood pressures on the thigh, calf, ankle and first...

  20. Study of the Effect of Hydro-Alcoholic Extract of Lactuca sativa on Arterial Blood Pressure and Heart Rate in Rats

    Directory of Open Access Journals (Sweden)

    R. Dehbooreh

    2013-04-01

    Full Text Available Introduction & Objective: Cardiovascular diseases are main causes of mortality and morbidity in the current world. Hypertension is one of the most important risk factors for the cardiovas-cular diseases. Herbal medicine is much regarded because of their natural source and less side effects. This study was done to evaluate the effects of hydro- alcoholic extract of Luc-tuca-Sativa (LS on blood pressure in rats. Materials & Methods: Hypertension was induced in the rats by Desoxycorticosterone (DOCA-Salt then the hypertension induction was confirmed by tail-cuff method before treatment. The effects of one week treatment by LS hydro-alcoholic extract (100 mg/kg/day on blood pressure; Heart Rate (HR and Plasma Renin Activity (PRA were investigated and compared with the control groups. Under anesthesia (urethane 1gr/kg Mean Arterial blood Pressure (MAP and HR were measured directly from Femoral Artery. In order to investigate the extract effects on MAP and HR, also possible mechanisms of these effects, intravenous injection of differ-ent concentrations of extract with and without pretreatment with histamine H1 receptor an-tagonist (Chlorpheniramine 10 mg/kg were performed. PRA was measured by radio-immuonoassay method. Urine volume was also measured during the treatment Results: The results of this study show that DOCA-Salt induced hypertension and decreased PRA in the rats. LS hydro- alcoholic extract treatment causes significant decrease of MAP in hypertension- treated group in comparison with non-treated group and also the level of PRA and urine volume increased by extract treatment. Our Findings showed that LS extract has no significant effect on HR. Conclusion: The results of this study indicated hat LS hydro- alcoholic extract due to interac-tion with kidney and diuretic effects decreased MAP and normalized PRA in the DOCA- Salt hypertensive. (Sci J Hamadan Univ Med Sci 2013; 20 (1:66-76

  1. Increased blood pressure in adult offspring of families with Balkan Endemic Nephropathy: a prospective study

    Directory of Open Access Journals (Sweden)

    Georgieva Rossitza B

    2006-08-01

    Full Text Available Abstract Background Previous studies have linked smaller kidney dimensions to increased blood pressure. However, patients with Balkan Endemic Nephropathy (BEN, whose kidneys shrink during the course of the disease, do not manifest increased blood pressure. The authors evaluated the relationship between kidney cortex width, kidney length, and blood pressure in the offspring of BEN patients and controls. Methods 102 offspring of BEN patients and 99 control offspring of non-BEN hospital patients in the Vratza District, Bulgaria, were enrolled in a prospective study and examined twice (2003/04 and 2004/05. Kidney dimensions were determined using ultrasound, blood pressure was measured, and medical information was collected. The parental disease of BEN was categorized into three groups: mother, father, or both parents. Repeated measurements were analyzed with mixed regression models. Results In all participants, a decrease in minimal kidney cortex width of 1 mm was related to an increase in systolic blood pressure of 1.4 mm Hg (p = 0.005. There was no association between kidney length and blood pressure. A maternal history of BEN was associated with an increase in systolic blood pressure of 6.7 mm Hg (p = 0.03; paternal BEN, +3.2 mm Hg (p = 0.35; or both parents affected, +9.9 mm Hg (p = 0.002. There was a similar relation of kidney cortex width and parental history of BEN with pulse pressure; however, no association with diastolic blood pressure was found. Conclusion In BEN and control offspring, a smaller kidney cortex width predisposed to higher blood pressure. Unexpectedly, a maternal history of BEN was associated with average increased systolic blood pressure in offspring.

  2. Increased diuresis, renal vascular reactivity, and blood pressure levels in young rats fed high sodium, moderately high fructose, or their association: a comparative evaluation.

    Science.gov (United States)

    Da Silva, Rita de Cássia Vilhena A F; de Souza, Priscila; da Silva-Santos, José Eduardo

    2016-12-01

    Excessive intakes of sodium or fructose have been described as risk factors for hypertension. We hypothesized that even a moderately high fructose diet (6% fructose), either alone or in combination with high sodium (4% NaCl), may impair diuresis and renal and systemic vascular reactivity, contributing to the onset of high blood pressure in rats. Male Wistar rats were fed chow containing 4% NaCl (HS), 6% fructose (MHF), or both 4% NaCl and 6% fructose (HSMHF) for 6 weeks and had their diuresis, plasma creatinine, vascular reactivity of perfused kidneys and systemic arterial pressure evaluated. We found no differences in augmented diuresis among animals given HS, MHF, or HSMHF diets. After 6 weeks both the HS and HSMHF groups had increased weight in their left kidneys, but only the HSMHF group showed augmented plasma creatinine. The effects of phenylephrine on renal vascular perfusion pressure were similarly enhanced in kidneys from the HS, MHF, and HSMHF groups, but not on the systemic arterial pressure. Although when evaluated in anesthetized rats, only the HSMHF group presented augmented blood pressure, evaluation in conscious animals revealed that both the MHF and HSMHF diets, but not the HS alone, were able to induce tachycardia and hypertension. In conclusion, a MHF diet containing 6% fructose was enough to render the renal vascular bed hyperreactive to phenylephrine and to induce both hypertension and tachycardia. The combination of 6% fructose with 4% NaCl led to plasma accumulation of creatinine and accelerated the development of tachycardia.

  3. Novel Approach for Ensuring Increased Validity in Home Blood Pressure Monitoring

    DEFF Research Database (Denmark)

    Wagner, Stefan Rahr; Toftegaard, Thomas Skjødeberg; Bertelsen, Olav Wedege

    This paper proposes a novel technique to increase the validity of home blood pressure monitoring by using various sensor technologies as part of an intelligent environment platform in the home of the user. A range of recommendations exists on how to obtain a valid blood pressure...

  4. Important role of PLC-γ1 in hypoxic increase in intracellular calcium in pulmonary arterial smooth muscle cells.

    Science.gov (United States)

    Yadav, Vishal R; Song, Tengyao; Joseph, Leroy; Mei, Lin; Zheng, Yun-Min; Wang, Yong-Xiao

    2013-02-01

    An increase in intracellular calcium concentration ([Ca(2+)](i)) in pulmonary arterial smooth muscle cells (PASMCs) induces hypoxic cellular responses in the lungs; however, the underlying molecular mechanisms remain incompletely understood. We report, for the first time, that acute hypoxia significantly enhances phospholipase C (PLC) activity in mouse resistance pulmonary arteries (PAs), but not in mesenteric arteries. Western blot analysis and immunofluorescence staining reveal the expression of PLC-γ1 protein in PAs and PASMCs, respectively. The activity of PLC-γ1 is also augmented in PASMCs following hypoxia. Lentiviral shRNA-mediated gene knockdown of mitochondrial complex III Rieske iron-sulfur protein (RISP) to inhibit reactive oxygen species (ROS) production prevents hypoxia from increasing PLC-γ1 activity in PASMCs. Myxothiazol, a mitochondrial complex III inhibitor, reduces the hypoxic response as well. The PLC inhibitor U73122, but not its inactive analog U73433, attenuates the hypoxic vasoconstriction in PAs and hypoxic increase in [Ca(2+)](i) in PASMCs. PLC-γ1 knockdown suppresses its protein expression and the hypoxic increase in [Ca(2+)](i). Hypoxia remarkably increases inositol 1,4,5-trisphosphate (IP(3)) production, which is blocked by U73122. The IP(3) receptor (IP(3)R) antagonist 2-aminoethoxydiphenyl borate (2-APB) or xestospongin-C inhibits the hypoxic increase in [Ca(2+)](i). PLC-γ1 knockdown or U73122 reduces H(2)O(2)-induced increase in [Ca(2+)](i) in PASMCs and contraction in PAs. 2-APB and xestospongin-C produce similar inhibitory effects. In conclusion, our findings provide novel evidence that hypoxia activates PLC-γ1 by increasing RISP-dependent mitochondrial ROS production in the complex III, which causes IP(3) production, IP(3)R opening, and Ca(2+) release, playing an important role in hypoxic Ca(2+) and contractile responses in PASMCs.

  5. Assessment of renal artery stenosis using both resting pressures ratio and fractional flow reserve: relationship to angiography and ultrasonography.

    Science.gov (United States)

    Kadziela, Jacek; Witkowski, Adam; Januszewicz, Andrzej; Cedro, Krzysztof; Michałowska, Ilona; Januszewicz, Magdalena; Kabat, Marek; Prejbisz, Aleksander; Kalińczuk, Lukasz; Zieleń, Piotr; Michel-Rowicka, Katarzyna; Warchoł, Ewa; Rużyłło, Witold

    2011-08-01

    BACKGROUND. Clinical benefit from renal artery revascularization remains controversial, probably because of inaccurate stenosis severity assessment. Objective. The aim of the study was to evaluate resting translesional pressures ratio and renal fractional flow reserve (rFFR) in relation to angiography and Doppler duplex ultrasonography in patients with at least moderate renal artery stenosis (RAS). METHODS. 44 hypertensive patients (48% of males, mean age 65 years) with at least moderate RAS were investigated. Translesional systolic pressure gradient (TSPG), resting Pd/Pa ratio (the ratio of mean distal to lesion and mean proximal pressures) and hyperemic rFFR - after intrarenal administration of papaverine - were evaluated. Quantitative angiographic analysis of stenosis severity was performed including minimal lumen diameter (MLD) and percent diameter stenosis (DS) assessment. Renal/aortic ratio (RAR), resistive index (RI) and deltaRI (side-to side difference) were obtained in Doppler-duplex ultrasonography. The predictive value of selected variables was calculated using receiver-operating characteristics curves. RESULTS. Mean Pd/Pa ratio was 0.86 ± 0.12 and decreased to 0.79 ± 0.13 after papaverine administration. Both Pd/Pa ratio and rFFR strongly correlated with TSPG (r = -0.92, p ratio and 0.80 for rFFR. CONCLUSIONS. Mean Pd/Pa ratio and rFFR strongly correlated with angiographic data and in less pronounced manner with ultrasound parameters reflecting intrarenal blood flow. The best accuracy cut-off points for severe RAS predicting were 0.93 and 0.80, respectively.

  6. Early increase in arterial lactate concentration under epinephrine infusion is associated with a better prognosis during shock.

    Science.gov (United States)

    Wutrich, Yann; Barraud, Damien; Conrad, Marie; Cravoisy-Popovic, Aurélie; Nace, Lionel; Bollaert, Pierre-Edouard; Levy, Bruno; Gibot, Sébastien

    2010-07-01

    To determine whether an epinephrine-induced early increase in arterial lactate concentration can prognosticate the outcome during shock state, we conducted a retrospective study in a 16-bed medical intensive care unit of a teaching hospital in France. One hundred consecutive patients admitted because of a shock state irrespective of etiology and treated with epinephrine were included. Patients were not enrolled if they received epinephrine administration before intensive care unit admission. Sequential arterial lactate measurements were performed at the time of epinephrine infusion (H0) and 4 h later (H4) in which Deltalactate was defined as (100 x [arterial lactate(H4)-arterial lactate(H0)]/arterial lactate(H0)) and expressed as a percentage. Etiology of shock was septic (82%), cardiogenic (10%), or hemorrhagic (8%). Twenty-eight-day mortality rate was 72%. At admission, arterial lactate concentration was elevated (4.96 +/- 3.8 mmol/L) and was further increased upon epinephrine administration, reaching a peak at H4 (8.22 +/- 3.66). When patients were stratified according to their outcome, nonsurvivors displayed the same pattern as survivors, although with a significant upward shift in values (ANOVA, P = 0.0003). The Sequential Organ Failure Assessment score and Deltalactate were the only variables associated with the 28-day risk of death, with an odds ratio of 1.32 (95% confidence interval [CI], 1.06-1.65; P = 0.01) and 0.99 (95% CI, 0.99-0.99; P = 0.03), respectively, in multivariate analysis. At a value of 100%, Deltalactate predicted death, with a 71% sensitivity (95% CI, 51%-87%) and a 67% specificity (95% CI, 43%-85%). Kaplan-Meier survival analysis confirmed this finding, with a 52.4% death rate among patients with Deltalactate greater than 100 comparatively to 84.7% when Deltalactate was less than 100 (log-rank test, P = 0.0002). An adapted response (lactate production) to a pharmacological trigger (epinephrine) is associated with better prognosis during

  7. Long-term excess fat and/or fructose ingestion causes changes in small artery K+ transporter expression and function with effects on blood pressure

    DEFF Research Database (Denmark)

    Olsen, A. K.; Salomonsson, M.; Sørensen, C. M.

    -fructose diet. HYPOTHESIS: A 28-week diet consisting of high-fat or high-fructose, or both, will lead to changes in K+ transporter expression and function, which will be linked with changes in blood pressure, arterial smooth muscle function, endothelial function and passive structural/mechanical properties....... METHODS: Male Sprague Dawley rats (4 weeks) were randomized into 4 diet groups receiving a diet with normal chow (CTR, N=19), high-fat chow (60% saturated fat, FAT, N=18), high-fructose (10% in drinking water; FRUC, N=15), or a combination of fat/fructose (FAT/FRUC, N=15) for 28 weeks. Systolic blood......M) in the FAT/FRUC group vs. CTR (PPressure myography showed no diet-induced differences in constrictions to high-KCl (75 mM), increasing phenylephrine (PE) concentrations, or the KV7 channel blocker XE-991 (10 µM). XE-991 reduced the Log(EC50) of PE...

  8. Low Physical Activity Is Associated With Increased Arterial Stiffness in Patients Recently Diagnosed With Type 2 Diabetes

    DEFF Research Database (Denmark)

    Funck, Kristian L; Laugesen, Esben; Høyem, Pernille;

    2015-01-01

    AIMS: Several studies have indicated that low physical activity is associated with increased risk of cardiovascular disease (CVD) and all-cause mortality among patients with diabetes. The association between physical activity and subclinical cardiovascular changes preceding clinical events remains...... to be elucidated. We investigated the relationship between physical activity and arterial stiffness, an independent predictor of CVD, in patients with type 2 diabetes and controls. METHODS: We included 100 patients with type 2 diabetes and 100 sex- and age-matched controls in a cross-sectional study. Arterial...... of physical activity was defined according to the median level of activity (cpm = 31). RESULTS: Sixty-five patients and 65 controls were included in the final analysis (median age 59 years, 55% men, median diabetes duration 1.9 years). Participants with low physical activity had higher cfPWV compared...

  9. Role of the medulla oblongata in normal and high arterial blood pressure regulation: the contribution of Escola Paulista de Medicina - UNIFESP.

    Science.gov (United States)

    Cravo, Sergio L; Campos, Ruy R; Colombari, Eduardo; Sato, Mônica A; Bergamaschi, Cássia M; Pedrino, Gustavo R; Ferreira-Neto, Marcos L; Lopes, Oswaldo U

    2009-09-01

    Several forms of experimental evidence gathered in the last 37 years have unequivocally established that the medulla oblongata harbors the main neural circuits responsible for generating the vasomotor tone and regulating arterial blood pressure. Our current understanding of this circuitry derives mainly from the studies of Pedro Guertzenstein, a former student who became Professor of Physiology at UNIFESP later, and his colleagues. In this review, we have summarized the main findings as well as our collaboration to a further understanding of the ventrolateral medulla and the control of arterial blood pressure under normal and pathological conditions.

  10. Opium addiction increases interleukin 1 receptor antagonist (IL-1Ra in the coronary artery disease patients.

    Directory of Open Access Journals (Sweden)

    Habibollah Saadat

    Full Text Available BACKGROUND: There is evidence that opium addiction has immunosuppressant effects. Coronary artery disease (CAD is a condition resulted from atherosclerosis which is dependent on the immune response. PURPOSE: To evaluate plasma levels of interleukin-6 and interleukin-1Ra in 30 patients with three-vessel coronary artery disease, ejection fraction of more than 35% and to evaluate their changes after prognostic treadmill test in 15 opium addicted and 15 non-addicted patients. METHODS: The participants underwent prognostic treadmill test and plasma levels of interleukin-6 (IL-6 and interleukin-1Ra (IL-1Ra were evaluated with ELISA method before, just after and 4 hours after the test. RESULTS: IL-1Ra (2183 pg/ml tended to decrease over time in the opium addicted group (1372 pg/ml after prognostic treadmill test and 1034 pg/ml 4 hours after that, although such decrease did not reach the statistical significance. IL-1Ra levels were significantly higher in opium addicted than in non addicted patients. Opium addiction had no significant effect on IL-6 changes. CONCLUSION: Consumption of opium in CAD patients is associated with higher IL-1Ra levels.

  11. Arginine methylation dysfunction increased risk of acute coronary syndrome in coronary artery disease population

    Science.gov (United States)

    Zhang, Shengyu; Zhang, Shuyang; Wang, Hongyun; Wu, Wei; Ye, Yicong

    2017-01-01

    Abstract The plasma levels of asymmetric dimethylarginine (ADMA) had been proved to be an independent cardiovascular risk factor. Few studies involved the entire arginine methylation dysfunction. This study was designed to investigate whether arginine methylation dysfunction is associated with acute coronary syndrome risk in coronary artery disease population. In total 298 patients undergoing coronary angiography because of chest pain with the diagnosis of stable angina pectoris or acute coronary syndrome from February 2013 to June 2014 were included. Plasma levels of free arginine, citrulline, ornithine, and the methylated form of arginine, ADMA, and symmetric dimethylarginine (SDMA) were measured with high-performance liquid chromatography coupled with tandem mass spectrometry. We examined the relationship between arginine metabolism-related amino acids or arginine methylation index (AMI, defined as ratio of [arginine + citrulline + ornithine]/[ADMA + SDMA]) and acute coronary events. We found that plasma ADMA levels were similar in the stable angina pectoris group and the acute coronary syndrome group (P = 0.88); the AMI differed significantly between 2 groups (P angina and acute coronary syndrome patients; AMI might be an independent risk factor of acute coronary events in coronary artery disease population. PMID:28207514

  12. DMPP-evoked increases in postganglionic sympathetic nerve activity and blood pressure occurs by two mechanisms in the rat.

    Science.gov (United States)

    Martin, J R

    1997-08-01

    1. Intravenous administration of the ganglionic nicotinic receptor agonist DMPP (1,1-dimethyl-4-phenylpiperazinium iodide) into urethane-anaesthetized rats evoked dose-dependent increases in mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA). 2. The ganglionic nicotinic receptor antagonists pentolinium and hexamethonium either alone or combined did not inhibit the increase in RSNA and MAP evoked by 50 to 200 micrograms kg-1 doses of DMPP. The increase in renal sympathetic nerve activity evoked by DMPP occurred as a brief burst in firing. 3. The increase in MAP, but not RSNA, evoked by DMPP in the presence of pentolinium was inhibited by the selective alpha 1-adrenergic receptor antagonist prazosin. 4. The non-selective alpha-adrenoceptor and NPY receptor antagonist benextramine also inhibited the increase in MAP without inhibiting the increase in RSNA. Surprisingly, the combination of benextramine and pentolinium, or benextramine and hexamethonium, completely blocked the DMPP-evoked increase in RSNA and thus the increase in MAP. 5. The uptake1 antagonist desipramine combined with pentolinium did not affect the DMPP-evoked increases in MAP or RSNA when compared to the responses evoked in the presence of pentolinium alone. 6. Adding the selective M1 muscarinic receptor antagonist telenzepine to pentolinium and prazosin did not inhibit the increase in RSNA evoked by a 100 micrograms kg-1 dose of DMPP. 7. While the DMPP-evoked increase in MAP in the presence of ganglionic nicotinic receptor antagonists is primarily dependent upon activation of alpha 1-adrenoceptors, the increase in RSNA occurs via activation of ganglionic nicotinic receptors and activation of a mechanism susceptible to blockade by benextramine.

  13. Avaliação das pressões venosa e arterial em cães submetidos a diferentes tipos de hipotensão Evaluation of venous and arterial blood pressures in dogs submitted to hypotension

    Directory of Open Access Journals (Sweden)

    R.C. Rabelo

    2005-12-01

    Full Text Available Estabeleceram-se a pressão venosa periférica (PVP, a pressão venosa central (PVC, a pressão arterial invasiva (PAI e a pressão arterial não invasiva (PANI em cães após diferentes eventos de hipotensão. Foram utilizados 15 cães adultos, distribuídos aleatoriamente em três grupos (G com cinco animais cada, submetidos aos seguintes eventos hipotensores: GI - cloridrato de xilazina a 2%, GII - choque hipovolêmico agudo e GIII - veneno da serpente Bothrops moojeni. Os animais, avaliados durante 30 minutos após o início do evento hipotensor, foram tratados com cloridrato de ioimbina (GI, amido hidroxietílico a 6% (GII e cetoprofeno (GIII e reavaliados por mais 30 minutos. Somente os animais do GII apresentaram redução da PVP após o evento hipotensor e aumento, 25 minutos após tratamento. Os cães dos grupos II e III mostraram redução da PVC após o evento hipotensor, e somente os animais do GII exibiram discreto aumento cinco minutos imediatamente após o tratamento. Houve diminuição da PAI e PANI nos dos grupos II e III após o evento hipotensor, com recuperação gradativa imediata, após o tratamento, somente da PAI.The peripheral venous pressure (PVP, the central venous pressure (CVP, the invasive (IAP and non-invasive blood pressure (NIAP in dogs submitted to different hypotensive events were studied. Fifteen adult mongrel dogs were randomly divided in three groups with five animals each, and submitted to hypotensive event as follow: GI - xylazine chloride 2%, GII - acute hypovolemic shock and GIII - snake venom (Bothrops moojeni. All animals were evaluated for 30 minutes after starting hypotensive event, treated with yoimbine chloride (GI, colloid hetastarch 6% (GII and ketoprofen (GIII and reevaluated for more 30 minutes. Only the group II dogs showed PVP decrease after hypotensive event, and increase 25 minutes after treatment. In animals of groups II and III, the CVP decreased after hypotensive event and only in GII

  14. Valores da pressão arterial em cães pelos métodos oscilométrico e Doppler vascular Arterial blood pressure in dogs by the oscilometric method and the Doppler ultrasonic

    Directory of Open Access Journals (Sweden)

    R.R. Cabral

    2010-02-01

    Full Text Available Foram comparados dois métodos não-invasivos de medida da pressão arterial, o Doppler vascular e o oscilométrico, com o objetivo de estabelecer parâmetros que possam auxiliar no diagnóstico seguro da hipertensão arterial. Para tal, foram utilizados 45 cães, machos e fêmeas, distribuídos em três grupos de acordo com o peso, pequeno, médio e grande porte. Em cada animal, procedeu-se a mensuração por meio do Doppler vascular e, em seguida, do oscilométrico. Na obtenção da pressão arterial sistólica, não houve diferença entre os métodos nos três grupos de animais, porém, na obtenção da pressão arterial diastólica, houve diferença estatística entre o Doppler vascular e o oscilométrico nos grupos de animais de pequeno e médio porte. Pôde-se concluir que valores confiáveis de pressão sistólica podem ser obtidos tanto por meio do Doppler vascular quanto do oscilométrico. Os valores da pressão arterial diastólica obtidos pelos dois métodos não se correlacionam, principalmente nos animais de pequeno e médio porte.Two noninvasive methods for blood pressure measurement, the oscilometric and the Doppler ultrasonic, were compaired aiming the establishment of parameters that can be helpful for the hypertension diagnosis. Forty-five dogs, males and females, were distributed in three groups, according to body weight: small, medium, and large sizes. In each animal, measurement of the blood pressure was performed, first by the Doppler ultrasonic, followed by the oscilometric method. No differences were observed in sistolic arterial pressure values obtained by both methods in none of the three animal groups. However, there was an important difference in diastolic arterial pressure values obtained by these methods, especially in small and medium size dogs. It was concluded that reliable results of sistolic blood pressure can be obtained both by the Doppler ultrasonic and the oscilometric method. Diastolic blood pressure

  15. Systolic blood pressure response after high-intensity interval exercise is independently related to decreased small arterial elasticity in normotensive African American women.

    Science.gov (United States)

    Carter, Stephen J; Goldsby, TaShauna U; Fisher, Gordon; Plaisance, Eric P; Gower, Barbara A; Glasser, Stephen P; Hunter, Gary R

    2016-05-01

    Aerobic exercise transiently lowers blood pressure. However, limited research has concurrently evaluated blood pressure and small arterial elasticity (SAE), an index of endothelial function, among African American (AA) and European American (EA) women the morning after (i.e., ≈22 h later) acute bouts of moderate-intensity continuous (MIC) and high-intensity interval (HII) exercise matched for total work. Because of greater gradients of shear stress, it was hypothesized that HII exercise would elicit a greater reduction in systolic blood pressure (SBP) compared to MIC exercise. After baseline, 22 AA and EA women initiated aerobic exercise training 3 times/week. Beginning at week 8, three follow-up assessments were conducted over the next 8 weeks at random to measure resting blood pressure and SAE. In total all participants completed 16 weeks of training. Follow-up evaluations were made: (i) in the trained state (TS; 8-16 weeks of aerobic training); (ii) ≈22 h after an acute bout of MIC exercise; and (iii) ≈22 h after an acute bout of HII exercise. Among AAs, the acute bout of HII exercise incited a significant increase in SBP (mm Hg) (TS, 121 ± 14 versus HII, 128 ± 14; p = 0.01) whereas responses (TS, 116 ± 12 versus HII, 113 ± 9; p = 0.34) did not differ in EAs. After adjusting for race, changes in SAE were associated (partial r = -0.533; p = 0.01) with changes in SBP following HII exercise. These data demonstrate an acute, unaccustomed bout of HII exercise produces physiological perturbations resulting in a significant increase in SBP that are independently associated with decreased SAE among AA women, but not EA women.

  16. Increased tea consumption is associated with decreased arterial stiffness in a Chinese population.

    Directory of Open Access Journals (Sweden)

    Chung-Hao Li

    Full Text Available BACKGROUND: Tea has attracted considerable attention for its potential cardioprotective effects. The primary chemical components of tea are thought to have a beneficial effect by reducing arterial stiffness. The objective of this study was to assess the association between tea consumption and brachial-ankle pulse wave velocity (baPWV in a relatively healthy Chinese population. METHODS: We enrolled 3,135 apparently healthy subjects from October 2006 to August 2009. Subjects taking medication for diabetes, hypertension, or hyperlipidemia, or with a history of cardiovascular disease, were excluded from the study. The subjects were categorized into three groups according to their tea-drinking habits: (1 none to low (n = 1615, defined as non-habitual tea drinkers, or drinking for 450 mL per day. Multiple logistic regression was used to determine whether different levels of consumption were independently associated with the highest quartile of baPWV values, defined as ≥1428.5 cm/s. RESULTS: Of the 3,135 subjects, 48.5% had drunk >150 mL of tea per day for at least 1 year. In multivariate regression analysis with adjustment for co-variables, including, age, sex, current smoking, alcohol use, habitual exercise, total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C ratio >5, obesity, newly diagnosed hypertension and diabetes, subjects with high tea consumption had a decreased risk of highest quartile of baPWV by 22% (odds ratio = 0.78, 95% confidence interval = 0.62-0.98, p = 0.032, while subjects with moderate tea consumption did not (p = 0.742, as compared subjects with none to low tea consumption. CONCLUSIONS: High, but not moderate, habitual tea consumption may decrease arterial stiffness.

  17. Exercise training prevents increased intraocular pressure and sympathetic vascular modulation in an experimental model of metabolic syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Castro, E.F.S. [Unidade de Hipertensão, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Mostarda, C.T. [Universidade Federal do Maranhão, São Luís, MA (Brazil); Rodrigues, B. [Laboratório do Movimento Humano, Universidade São Judas Tadeu, São Paulo, SP (Brazil); Moraes-Silva, I.C. [Unidade de Hipertensão, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Feriani, D.J. [Laboratório do Movimento Humano, Universidade São Judas Tadeu, São Paulo, SP (Brazil); De Angelis, K. [Laboratório de Fisiologia Translacional, Universidade Nove de Julho, São Paulo, SP (Brazil); Irigoyen, M.C. [Unidade de Hipertensão, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil)

    2015-02-13

    The present study aimed to study the effects of exercise training (ET) performed by rats on a 10-week high-fructose diet on metabolic, hemodynamic, and autonomic changes, as well as intraocular pressure (IOP). Male Wistar rats receiving fructose overload in drinking water (100 g/L) were concomitantly trained on a treadmill for 10 weeks (FT group) or kept sedentary (F group), and a control group (C) was kept in normal laboratory conditions. The metabolic evaluation comprised the Lee index, glycemia, and insulin tolerance test (KITT). Arterial pressure (AP) was measured directly, and systolic AP variability was performed to determine peripheral autonomic modulation. ET attenuated impaired metabolic parameters, AP, IOP, and ocular perfusion pressure (OPP) induced by fructose overload (FT vs F). The increase in peripheral sympathetic modulation in F rats, demonstrated by systolic AP variance and low frequency (LF) band (F: 37±2, 6.6±0.3 vs C: 26±3, 3.6±0.5 mmHg{sup 2}), was prevented by ET (FT: 29±3, 3.4±0.7 mmHg{sup 2}). Positive correlations were found between the LF band and right IOP (r=0.57, P=0.01) and left IOP (r=0.64, P=0.003). Negative correlations were noted between KITT values and right IOP (r=-0.55, P=0.01) and left IOP (r=-0.62, P=0.005). ET in rats effectively prevented metabolic abnormalities and AP and IOP increases promoted by a high-fructose diet. In addition, ocular benefits triggered by exercise training were associated with peripheral autonomic improvement.

  18. Exercise training prevents increased intraocular pressure and sympathetic vascular modulation in an experimental model of metabolic syndrome

    Directory of Open Access Journals (Sweden)

    E.F.S. Castro

    2015-04-01

    Full Text Available The present study aimed to study the effects of exercise training (ET performed by rats on a 10-week high-fructose diet on metabolic, hemodynamic, and autonomic changes, as well as intraocular pressure (IOP. Male Wistar rats receiving fructose overload in drinking water (100 g/L were concomitantly trained on a treadmill for 10 weeks (FT group or kept sedentary (F group, and a control group (C was kept in normal laboratory conditions. The metabolic evaluation comprised the Lee index, glycemia, and insulin tolerance test (KITT. Arterial pressure (AP was measured directly, and systolic AP variability was performed to determine peripheral autonomic modulation. ET attenuated impaired metabolic parameters, AP, IOP, and ocular perfusion pressure (OPP induced by fructose overload (FT vs F. The increase in peripheral sympathetic modulation in F rats, demonstrated by systolic AP variance and low frequency (LF band (F: 37±2, 6.6±0.3 vs C: 26±3, 3.6±0.5 mmHg2, was prevented by ET (FT: 29±3, 3.4±0.7 mmHg2. Positive correlations were found between the LF band and right IOP (r=0.57, P=0.01 and left IOP (r=0.64, P=0.003. Negative correlations were noted between KITT values and right IOP (r=-0.55, P=0.01 and left IOP (r=-0.62, P=0.005. ET in rats effectively prevented metabolic abnormalities and AP and IOP increases promoted by a high-fructose diet. In addition, ocular benefits triggered by exercise training were associated with peripheral autonomic improvement.

  19. Noninvasive assessment of pulmonary arterial pressure by krypton-81m right cardiac ventriculography in patients with chronic obstructive pulmonary disease

    Energy Technology Data Exchange (ETDEWEB)

    Yamaoka, Shimpachi; Kuriyama, Takanobu; Hirai, Masashi; Nishimura, Kouichi; Kuno, Kenshi; Yonekura, Yoshiharu

    1987-10-01

    In twenty patients with COPD, the following pulmonary function test values were obtained (mean +- SD): FEV/sub 1.0/ = 1070 +- 490 ml;FEV/sub 1.0/ % = 47.7 +- 8.9 %;PaO/sub 2/ = 65.8 +- 8.4 torr;PaCO/sub 2/ = 39.7 +- 4.4 torr. All patients underwent right heart catheterization and pulmonary arterial mean pressures (PAMP) were obtained. The PAMP value was 20.2 +- 4.1 torr (range 12 - 28), RVEF was 52.2 +- 8.4 % (range 31 - 63) and RVRFR was 25.5 +- 4.7 %100 msec (range 18 - 34). The PAMP negatively correlated with the RVEF (r = -0.69, p < 0.001) and RVRFR (r = -0.82, p < 0.001). In ten healthy male subjects, the RVEF was 56.6 +- 5.1 % (range 50 - 64) and RVRFR was 37.7 +- 3.0 %100 msec (range 33 - 42). The lower limit of normal for the RVEF was regarded as 46.4 % and that of the RVRFR as 31.7 %100 msec;these are the values two standard deviations below the means. Nine of the twenty patients has a PAMP value of more than 20 torr (the sine qua non of cor pulmonale). Five of these nine patients had RVEF values less than 46.4 % and all of them had RVRFR values of less than 31.7 %100 msec. On the other hand, all of the remaining eleven patients (PAMP 20 torr or less) had RVEF values within the normal range, but ten of the eleven had RVRFR values of less than 31.7 %100 msec. Therefore, the RVRFR value, which showed excellent correlation with the PAMP, provided a noninvasive assessment of pulmonary arterial pressure with good sensitivity in detecting elevated pressure. The RVEF value supplemented the RVRFR with good specificity for detection of elevation of pressure;that is, it eliminated false positive results. (J.P.N.)

  20. Effect of continuous positive airway pressure on arterial stiffness in patients with obstructive sleep apnea and hypertension: a meta-analysis.

    Science.gov (United States)

    Lin, Xin; Chen, Gongping; Qi, Jiachao; Chen, Xiaofang; Zhao, Jiangming; Lin, Qichang

    2016-12-01

    Arterial stiffness has been recognized as a predictor of cardiovascular and all-cause mortality in hypertensive patients. However, the impact of continuous positive airway pressure (CPAP) on arterial stiffness in patients with OSA and hypertension remains inconclusive. We performed a meta-analysis to determine whether effective CPAP therapy could decrease arterial stiffness. Two reviewers independently searched PubMed, Embase, Web of Science and Cochrane Library prior to March 5, 2015. Information on characteristics of subjects, study design and pre- and post-CPAP treatment of arterial stiffness was extracted for analysis. Standardized mean difference (SMD) was used to analyze the summary estimates for CPAP therapy. Three articles with 186 patients were included in this meta-analysis, including two observational studies and one randomized controlled study. The meta-analysis showed that CPAP was associated with a statistically significant decrease in arterial stiffness in patients with OSA and hypertension (SMD = -0.65, 95 % confidence interval (CI) = -1.14 to -0.16, z = 2.60, p = 0.009). Our meta-analysis suggested that CPAP among OSA and hypertensive patients was significantly associated with a decrease in arterial stiffness. Further prospective large-scale multicenter RCTs are needed to explore the precise impact of CPAP therapy on arterial stiffness in patients with OSA and hypertension.

  1. Daily liquorice consumption for two weeks increases augmentation index and central systolic and diastolic blood pressure.

    Directory of Open Access Journals (Sweden)

    Miia H Leskinen

    Full Text Available Liquorice ingestion often elevates blood pressure, but the detailed haemodynamic alterations are unknown. We studied haemodynamic changes induced by liquorice consumption in 20 subjects versus 30 controls with average blood pressures of 120/68 and 116/64 mmHg, respectively.Haemodynamic variables were measured in supine position before and after two weeks of liquorice consumption (daily glycyrrhizin dose 290-370 mg with tonometric recording of radial blood pressure, pulse wave analysis, and whole-body impedance cardiography. Thirty age-matched healthy subjects maintaining their normal diet were studied as controls.Two weeks of liquorice ingestion elevated peripheral and central systolic and diastolic blood pressure (by 7/4 and 8/4 mmHg, 95% confidence intervals [CI] 2-11/1-8 and 3-13/1-8, respectively, P<0.05, and increased extracellular volume by 0.5 litres (P<0.05 versus controls. Also augmentation index adjusted to heart rate 75/min (from 7% to 11%, 95% CI for change 0.3-7.5, P<0.05 and aortic pulse pressure (by 4 mmHg, 95% CI 1-7, P<0.05 were elevated indicating increased wave reflection from the periphery. In contrast, peripheral (-3/-0.3 mmHg and central blood pressure (-2/-0.5 mmHg, aortic pulse pressure (-1 mmHg, and augmentation index adjusted to heart rate 75/min (from 9% to 7% decreased numerically but not statistically significantly without changes in extracellular volume in the control group. Heart rate, systemic vascular resistance, cardiac output, and pulse wave velocity did not differ between the groups.Two weeks of daily liquorice consumption increased extracellular volume, amplified pressure wave reflection from the periphery, and elevated central systolic and diastolic blood pressure.EU Clinical Trials Register EudraCT 2006-002065-39 ClinicalTrials.gov NCT01742702.

  2. Presence of anomalous coronary seen on angiogram is not associated with increased risk of significant coronary artery disease.

    Science.gov (United States)

    Suryanarayana, Prakash; Kollampare, Shubha; Riaz, Irbaz Bin; Lee, Justin; Husnain, Muhammad; Luni, Faraz Khan; Movahed, Mohammad Reza

    2014-12-01

    It is unclear if anomalous coronary arteries are at higher risk for atherosclerosis. The link between anomalous coronary artery and early coronary artery disease has been suggested. The aim of this study is to determine whether the coronary artery anomaly predisposes to development of significant coronary disease. Using retrospective chart review, patients with documented anomalous coronary arteries recognized during coronary angiography between years 2000 to 2007 were analyzed. Prevalence of significant atherosclerotic coronary artery disease (defined as more than 50% luminal narrowing) was compared between normal and anomalous coronaries. A total of 147 patients with anomalous coronary arteries were found. Right coronary artery was the most common anomalous artery 128 of 148 (86.5%) in our dataset. There was no difference in the occurrence of atherosclerosis between anomalous and nonanomalous coronaries. Significant atherosclerosis was present in 59 of the 148 anomalous coronary arteries (37.8%), and 112 of the 293 nonanomalous coronary arteries (38.2%, p = 0.9). On the basis of our study, there is no evidence that anomalous coronary arteries predispose to significant coronary artery disease in comparison to normal coronary arteries.

  3. Increased brachial-ankle pulse wave velocity is associated with impaired endothelial function in patients with coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    LIU Dong-hong; TAO Jun; WANG Yan; LIAO Xin-xue; XU Ming-guo; WANG Jie-mei; YANG Zhen; CHEN Long; L(U) Ming-de; LU Kun

    2006-01-01

    Background Pulse wave velocity and flow-mediated vasodilation (FMD) are widely used as noninvasive modalities for evaluating atherosclerosis. However, it is not known whether pulse wave velocity is related to FMD in patients with coronary artery disease (CAD). Therefore, the present study was designed to investigate the alteration in brachial-ankle pulse wave velocity (baPWV) and endothelial function in CAD patients.Methods Thirty-three patients with CAD and thirty control subjects were recruited for this study. baPWV was measured non-invasively using a VP 1000 automated PWV/ABI analyzer (PWV/ABI, Colin Co. Ltd., Komaki,Japan). Endothelial function as reflected by FMD in the brachial artery was assessed with a high-resolution ultrasound device.Results baPWV was increased in CAD patients compared with control subjects [(1756.1±253.1) cm/s vs(1495.3 ± 202.3) cm/s, P<0.01]. FMD was significantly reduced in CAD patients compared with control subjects[(5.2±2.1) % vs (11.1 ±4.4) %, P<0.01]. baPWV correlated with FMD (r =-0.68, P<0.001). The endothelium-independent vasodilation induced by sublingual nitroglycerin in the brachial artery was similar in the CAD group compared with the control group.Conclusions CAD is associated with increased baPWV and endothelial dysfunction. Increased baPWV parallels diminished endothelial function. Our data therefore suggest that baPWV can be used as a noninvasive surrogate index in clinical evaluation of endothelial function.

  4. Genetic predisposition to higher blood pressure increases risk of incident hypertension and cardiovascular diseases in Chinese.

    Science.gov (United States)

    Lu, Xiangfeng; Huang, Jianfeng; Wang, Laiyuan; Chen, Shufeng; Yang, Xueli; Li, Jianxin; Cao, Jie; Chen, Jichun; Li, Ying; Zhao, Liancheng; Li, Hongfan; Liu, Fangcao; Huang, Chen; Shen, Chong; Shen, Jinjin; Yu, Ling; Xu, Lihua; Mu, Jianjun; Wu, Xianping; Ji, Xu; Guo, Dongshuang; Zhou, Zhengyuan; Yang, Zili; Wang, Renping; Yang, Jun; Yan, Weili; Gu, Dongfeng

    2015-10-01

    Although multiple genetic markers associated with blood pressure have been identified by genome-wide association studies, their aggregate effect on risk of incident hypertension and cardiovascular disease is uncertain, particularly among East Asian who may have different genetic and environmental exposures from Europeans. We aimed to examine the association between genetic predisposition to higher blood pressure and risk of incident hypertension and cardiovascular disease in 26 262 individuals in 2 Chinese population-based prospective cohorts. A genetic risk score was calculated based on 22 established variants for blood pressure in East Asian. We found the genetic risk score was significantly and independently associated with linear increases in blood pressure and risk of incident hypertension and cardiovascular disease (P range from 4.57×10(-3) to 3.10×10(-6)). In analyses adjusted for traditional risk factors including blood pressure, individuals carrying most blood pressure-related risk alleles (top quintile of genetic score distribution) had 40% (95% confidence interval, 18-66) and 26% (6-45) increased risk for incident hypertension and cardiovascular disease, respectively, when compared with individuals in the bottom quintile. The genetic risk score also significantly improved discrimination for incident hypertension and cardiovascular disease and led to modest improvements in risk reclassification for cardiovascular disease (all the Phypertension and cardiovascular disease and provides modest incremental information to cardiovascular disease risk prediction. The potential clinical use of this panel of blood pressure-associated polymorphisms remains to be determined.

  5. The lingering dilemma of arterial pressure in CKD : what do we know, where do we go?

    NARCIS (Netherlands)

    Agarwal, Rajiv; Martinez-Castelao, Alberto; Wiecek, Andrzej; Massy, Ziad; Suleymanlar, Gultekin; Ortiz, Alberto; Blankestijn, Peter J.; Covic, Adrian; Dekker, Friedo W.; Jager, Kitty J.; Lindholm, Bengt; Goldsmith, David; Fliser, Danilo; London, Gerard; Zoccali, Carmine

    2011-01-01

    Despite many advances in the management of hypertensive chronic kidney disease (CKD) patients, both on and off dialysis, there exist several gaps in our knowledge. Although the modern techniques to measure blood pressure (BP) indirectly have been available for a long time, among those with CKD, how

  6. [Method of continuous direct recording of arterial pressure from a mercury manometer].

    Science.gov (United States)

    Antelava, A L

    1978-01-01

    The article describes a transducer for continuous recording of the readings of a mercury manometer in which, to simplify the construction and calibration, the transducer of pressure changes to electric current changes is made of high-resistant (nichrome) wire passed through the tube of the mercury manometer and incorporated in the circuit of the measuring bridge.

  7. Small artery structure adapts to vasodilatation rather than to blood pressure during antihypertensive treatment

    DEFF Research Database (Denmark)

    2007-01-01

    . RESULTS: In group A, mean ambulatory blood pressure (ABP) fell from 119 +/- 2 (SE) to 103 +/- 2 mmHg (P 1 to 99 +/- 1 mmHg, P = NS). Both groups showed similar reductions in Rrest (-33.4 and -28.5%, respectively) and in Rmin (-15.4 and -15...

  8. Sex Comparisons in Muscle Sympathetic Nerve Activity and Arterial Pressure Oscillations During Progressive Central Hypovolemia

    Science.gov (United States)

    2015-01-01

    Baroreflex activity, blood Loss, gender , lower body negative pressure. Correspondence Robert Carter III, US Army Institute of Surgical Research, Fort...information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and...adrenoreceptor responsiveness, greater vasoconstriction under equal LBNP, lower levels of total circulating norepinephrine (NE) at presyncope, and lower

  9. THEORETICAL ANALYSIS ON HYDRAULIC TRANSIENT RESULTED BY SUDDEN INCREASE OF INLET PRESSURE FOR LAMINAR PIPELINE FLOW

    Institute of Scientific and Technical Information of China (English)

    邓松圣; 周绍骑; 廖振方; 邱正阳; 曾顺鹏

    2004-01-01

    Hydraulic transient,which is resulted from sudden increase of inlet pressure for laminar pipeline flow,is studied.The partial differential equation,initial and boundary conditions for transient pressure were constructed,and the theoretical solution was obtained by variable-separation method.The partial differential equation,initial and boundary conditions for flow rate were obtained in accordance with the constraint correlation between flow rate and pressure while the transient flow rate distribution was also solved by variable-separation method.The theoretical solution conforms to numerical solution obtained by method of characteristics(MOC)very well.

  10. Relations between a novel, reliable, and rapid index of arterial compliance (PP-HDI) and well-established inidices of arterial blood pressure (ABP) in a sample of hypertensive elderly subjects.

    Science.gov (United States)

    Bergamini, L; Finelli, M E; Bendini, C; Ferrari, E; Veschi, M; Neviani, F; Manni, B; Pelosi, A; Rioli, G; Neri, M

    2009-01-01

    Hypertension is a risk factor for a long-lasting arterial wall-remodelling leading to stiffness. The rapid method measuring the pulse pressure (PP) by means of the tool of Hypertension Diagnostic Instruments (HDI) called PP-HDI, overcomes some of the problems arising with more-time consuming methods, like ambulatory blood pressure monitoring (ABPM), and give information about the elasticity of the arterial walls. We studied the relationship between the PP-HDI, the large artery compliance (LA-C) and small artery compliance (SA-C) and few well-established indices of arterial blood pressure (ABP) in a sample of 75 hypertensive subjects, aged 65 years and over. Significant correlations between LA-C and heart rate (HR), PP-ABPM and PP-HDI were found. SA-C relates with HR and systolic blood pressure (SBP) measured in lying and standing positions. Applying a stepwise regression analysis, we found that LA-C variance stems from PP-HDI and HR, while SA-C variance stems from SBP in lying position. Receiver operator characteristic (ROC) curves for thresholds of PP showed that PP-HDI reached levels of sensitivity/specificity similar to PP-ABPM. In conclusion, surveillance of ABP through hemo-dynamic indices, in particular of SBP, is essential, nevertheless the advantage of this control is not known in an elderly population where the organ damage is already evident. PP needs necessarily an instrumental measurement. The PP-HDI result is similar in reliability with respect to PPABPM, but is more rapid and well applicable in an elderly population.

  11. The minor symptoms of increased intracranial pressure: 101 patients with benign intracranial hypertension.

    Science.gov (United States)

    Round, R; Keane, J R

    1988-09-01

    Of 101 patients with benign intracranial hypertension not related to vasculitis, neck stiffness occurred in 31, tinnitus in 27, distal extremity paresthesias in 22, joint pains in 13, low back pain in 5, and gait "ataxia" in 4. Symptoms resolved promptly upon lowering the intracranial pressure by lumbar puncture, and were probably directly caused by intracranial hypertension. Awareness of these "minor" symptoms of increased intracranial pressure can facilitate diagnosis and management.

  12. Pressão arterial de adolescentes de escolas particulares de Fortaleza-CE Presión arterial de adolescentes de escuelas particulares en Fortaleza-CE Blood pressure of adolescents in private schools in Fortaleza-CE

    Directory of Open Access Journals (Sweden)

    Polyana Carina Viana da Silva

    2010-01-01

    Full Text Available OBJETIVO: Identificar a pressão arterial de adolescentes de escolas particulares da cidade de Fortaleza-CE. MÉTODOS: Estudo do tipo quantitativo com delineamento transversal no qual foram investigados 794 adolescentes, entre 12-17 anos de idade de 14 escolas privadas dessa cidade no período de março a setembro de 2007, mediante aplicação de um formulário que abrangeu o registro das características sóciodemográficas, pressão arterial, Índice de Massa Corporal (IMC, prática de atividade física e glicemia capilar. RESULTADOS: Verificou-se que 19,7% dos jovens apresentavam pressão arterial elevada. Os adolescentes do sexo masculino apresentaram pressão arteial sistólica (PAS e pressão arterial diastólica (PAD maiores do que a do sexo feminino (p=0,0001. A pesquisa constatou valores maiores de PAS e PAD naqueles com excesso de peso (p=0,0001. CONCLUSÃO: A pressão arterial foi influenciada sobretudo pelo sexo e IMC.OBJETIVO: Identificar la presión arterial de adolescentes de escuelas particulares en la ciudad de Fortaleza-CE. MÉTODOS: Se trata de un estudio cuantitativo con delineamiento transversal en el cual fueron investigados 794 adolescentes - entre 12 y 17 años de edad - de 14 escuelas privadas de esa ciudad, en el período de marzo a septiembre de 2007. Se utilizó un formulario que contempló el registro de las siguientes características: socio-demográficas, presión arterial, Índice de Masa Corporal (IMC, práctica de actividad física y, glucemia capilar. RESULTADOS: Se verificó que 19,7% de los jóvenes presentaban presión arterial elevada. Los adolescentes del sexo masculino presentaron presión arterial sistólica (PAS y presión arterial diastólica (PAD mayores que las del sexo femenino (p=0,0001. La investigación constató valores mayores de PAS y PAD en aquellos con exceso de peso (p=0,0001. CONCLUSIÓN: La presión arterial fue influenciada, sobre todo, por el sexo y el IMC.OBJECTIVE: To identify the

  13. Calibrated versus uncalibrated arterial pressure waveform analysis in monitoring cardiac output with transpulmonary thermodilution in patients with severe sepsis and septic shock: an observational study

    NARCIS (Netherlands)

    Slagt, C.; Helmi, M.; Malagon, I.; Groeneveld, A.B.

    2015-01-01

    BACKGROUND: Cardiac output (CO) measurement is often required in critically ill patients. The performances of newer, less invasive techniques require evaluation in patients with severe sepsis and septic shock. OBJECTIVES: To compare calibrated arterial pressure waveform analysis-derived CO (COap, Vo

  14. Effect of Positive Airway Pressure on Cardiovascular Outcomes in Coronary Artery Disease Patients with Non-Sleepy Obstructive Sleep Apnea : The RICCADSA Randomized Controlled Trial

    NARCIS (Netherlands)

    Peker, Yüksel; Glantz, Helena; Eulenburg, Christine; Wegscheider, Karl; Herlitz, Johan; Thunström, Erik

    2016-01-01

    RATIONALE: Obstructive sleep apnea is common in patients with coronary artery disease, many of whom do not report daytime sleepiness. First-line treatment for symptomatic obstructive sleep apnea is continuous positive airway pressure, but its value in patients without daytime sleepiness is uncertain

  15. Pomegranate juice consumption for 3 years by patients with carotid artery stenosis reduces common carotid intima-media thickness, blood pressure and LDL oxidation.

    Science.gov (United States)

    Aviram, Michael; Rosenblat, Mira; Gaitini, Diana; Nitecki, Samy; Hoffman, Aaron; Dornfeld, Leslie; Volkova, Nina; Presser, Dita; Attias, Judith; Liker, Harley; Hayek, Tony

    2004-06-01

    Dietary supplementation with polyphenolic antioxidants to animals was shown to be associated with inhibition of LDL oxidation and macrophage foam cell formation, and attenuation of atherosclerosis development. We investigated the effects of pomegranate juice (PJ, which contains potent tannins and anthocyanins) consumption by atherosclerotic patients with carotid artery stenosis (CAS) on the progression of carotid lesions and changes in oxidative stress and blood pressure. Ten patients were supplemented with PJ for 1 year and five of them continued for up to 3 years. Blood samples were collected before treatment and during PJ consumption. In the control group that did not consume PJ, common carotid intima-media thickness (IMT) increased by 9% during 1 year, whereas, PJ consumption resulted in a significant IMT reduction, by up to 30%, after 1 year. The patients' serum paraoxonase 1 (PON 1) activity was increased by 83%, whereas serum LDL basal oxidative state and LDL susceptibility to copper ion-induced oxidation were both significantly reduced, by 90% and 59%, respectively, after 12 months of PJ consumption, compared to values obtained before PJ consumption. Furthermore, serum levels of antibodies against oxidized LDL were decreased by 19%, and in parallel serum total antioxidant status (TAS) was increased by 130% after 1 year of PJ consumption. Systolic blood pressure was reduced after 1 year of PJ consumption by 12% [corrected] and was not further reduced along 3 years of PJ consumption. For all studied parameters, the maximal effects were observed after 1 year of PJ consumption. Further consumption of PJ, for up to 3 years, had no additional beneficial effects on IMT and serum PON1 activity, whereas serum lipid peroxidation was further reduced by up to 16% after 3 years of PJ consumption. The results of the present study thus suggest that PJ consumption by patients with CAS decreases carotid IMT and systolic blood pressure and these effects could be related to

  16. The pharmacist and the management of arterial hypertension: the role of blood pressure monitoring and telemonitoring.

    Science.gov (United States)

    Omboni, Stefano; Sala, Elisa

    2015-02-01

    Randomized controlled trials have documented that a team of health care professionals which includes a physician, a nurse and a community pharmacist may improve the benefit and adherence of anti-hypertensive therapy. If such a health care model relies on blood pressure telemonitoring, it can promote a stronger relationship between health care professionals and patients, and further improve BP control of hypertension. The major benefit of this collaborative approach is to center the patient's management in a tailored way, providing comprehensive and preventive care based on health information technologies. In this review, the authors summarize recent clinical studies that evaluate the role of the community pharmacist in BP measurements, and in hypertension screening and control. The authors also describe the advantages of using blood pressure telemonitoring in home and ambulatory settings to evaluate potential alternatives to primary care in hypertension management.

  17. Technology and application of pressure relief and permeability increase by jointly drilling and slotting coal

    Institute of Scientific and Technical Information of China (English)

    Lin Baiquan; Zhang Jianguo; Shen Chunming; Zhang Qizhi; Sun Chen

    2012-01-01

    Difficulties with soft coal seams having a high gas content and high stress levels can be addressed by a technology of pressure relief and permeability increase.Slotting the seam by auxiliary drilling with a water jet that breaks the coal and slots the coal seam during the process of retreat drilling achieves pressure relief and permeability increase.Improved efficiency of gas extraction from a field test,high gas coal seam was observed.Investigating the theory of pressure relief and permeability increase required analyzing the characteristics of the double power slotting process and the effects of coal pressure relief and permeability increase.The influence of confining pressure on coal physical properties was examined by using FLAC3D software code to simulate changes of coal stress within the tool destruction area.The double power joint drilling method was modeled.Field experiments were performed and the effects are analyzed.This research shows that there is an "islanding effect" in front of the joint double power drill and slotting equipment.The failure strength of the coal seam is substantially reduced within the tool destruction area.Drilling depths are increased by 72% and the diameter of the borehole is increased by 30%.The amount of powdered coal extracted from the drill head increases by 17 times when using the new method.A 30 day total flow measurement from the double power drilled and slotted bores showed that gas extraction increased by 1.3 times compared to the standard drilled bores.Gas concentrations increased from 30% to 60% and were more stable so the overall extraction efficiency increased by a factor of two times.

  18. Noradrenaline-induced increases in calcium and tension in skeletal muscle conductance and resistance arteries from rats with post-infarction heart failure

    DEFF Research Database (Denmark)

    Trautner, Simon; Amtorp, Ole; Boesgaard, Soren

    2006-01-01

    -operated rats, skeletal muscle conductance and resistance arteries (mean lumen diameters: 514 and 186 microm) were isolated and mounted on wire myographs, and wall tension was recorded in response to cumulative application of acetylcholine and noradrenaline to the vessel segments. In a subset of experiments......, wall tension and cytosolic free calcium ion concentration [Ca(2+)](i) were recorded simultaneously during noradrenaline application, using wire myography and the FURA-2 technique. No significant differences were found in the arterial baseline levels of [Ca(2+)](i) or tension between CHF and sham rats....... In the resistance arteries of CHF rats, the noradrenaline-induced increases in [Ca(2+)](i) were significantly enhanced (P=0.003). Despite the augmented [Ca(2+)](i) levels, the tension responses to noradrenaline were unaltered in these arteries. In the conductance arteries, there were no significant differences...

  19. Hydrostatic Pressure Affects In Vitro Maturation of Oocytes and Follicles and Increases Granulosa Cell Death

    Directory of Open Access Journals (Sweden)

    Isac Karimi

    2013-01-01

    Full Text Available Objective: This study examines the effects of hydrostatic pressure on in vitro maturation (IVM of oocytes derived from in vitro grown follicles.Materials and Methods: In this experimental study, preantral follicles were isolated from 12-day-old female NMRI mice. Each follicle was cultured individually in Alpha Minimal Essential Medium (α-MEM under mineral oil for 12 days. Then, follicles were induced for IVM and divided into two groups, control and experiment. In the experiment group follicles were subjected to 20 mmHg pressure for 30 minutes and cultured for 24-48 hours. We assessed for viability and IVM of the oocytes. The percentage of apoptosis in cumulus cells was determined by the TUNEL assay. A comparison between groups was made using the student’s t test.Results: The percentage of metaphase II oocytes (MII increased in hydrostatic pressure-treated follicles compared to controls (p<0.05. Cumulus cell viability reduced in hydrostatic pressure-treated follicles compared to controls (p<0.05. Exposure of follicles to pressure increased apoptosis in cumulus cells compared to controls (p<0.05.Conclusion: Hydrostatic pressure, by inducing apoptosis in cumulus cells, participates in the cumulus oocyte coupled relationship with oocyte maturation.

  20. Prevalence and correlates of increased lung/heart ratio of thallium-201 during dipyridamole stress imaging for suspected coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Villanueva, F.S.; Kaul, S.; Smith, W.H.; Watson, D.D.; Varma, S.K.; Beller, G.A. (Univ. of Virginia School of Medicine, Charlottesville (USA))

    1990-12-01

    There is little information concerning the prevalence and clinical correlates of increased pulmonary thallium-201 uptake during dipyridamole thallium-201 stress imaging. Accordingly, the clinical characteristics and quantitative thallium-201 findings were correlated with quantitative lung/heart thallium-201 ratio in 87 patients undergoing dipyridamole thallium-201 stress testing. Nineteen patients (22%) had an elevated ratio (greater than 0.51). These patients were more likely to have had an infarction, to be taking beta blockers, and have a lower rate-pressure product after dipyridamole administration than those with a normal ratio (p less than 0.03). An elevated ratio was associated with a greater likelihood of initial, redistribution and persistent defects, as well as left ventricular cavity dilatation on thallium-201 imaging (p less than 0.05). In addition, the number of myocardial segments demonstrating initial, redistribution and persistent defects was also greater in patients with increased ratios (p less than 0.03). Multivariate analysis demonstrated that the presence of redistribution and left ventricular cavity dilatation were the most significant correlates of lung/heart thallium-201 ratio. It is concluded that the prevalence of increased lung/heart thallium-201 ratio with dipyridamole thallium-201 stress imaging is similar to that seen with exercise stress imaging. As with exercise thallium-201 imaging, increased pulmonary thallium-201 uptake may be a marker of functionally more significant coronary artery disease.

  1. Hydrogen peroxide increases nerve-evoked contractions in mouse tail artery by an endothelium-dependent mechanism.

    Science.gov (United States)

    Reardon, Trent F; Brock, James A

    2013-01-05

    Reactive oxygen species contribute to regulating the excitability of vascular smooth muscle. This study investigated the actions of the relatively stable reactive oxygen species, H(2)O(2), on nerve-evoked contractions of mouse distal tail artery. H(2)O(2) (10-100 μM) increased nerve-evoked contractions of isometrically mounted segments of tail artery. Endothelium denudation increased nerve-evoked contractions and abolished the facilitatory effect of H(2)O(2). Inhibition of nitric oxide synthase with L-nitroarginine methyl ester (0.1mM) also increased nerve-evoked contractions and reduced the late phase of H(2)O(2)-induced facilitation. H(2)O(2)-induced facilitation of nerve-evoked contractions depended, in part, on synthesis of prostanoids and was reduced by the cyclooxygenase inhibitor indomethacin (1 μM) and the thromboxane A(2) receptor antagonist SQ 29548 (1 μM). H(2)O(2) increased sensitivity of nerve-evoked contractions to the α(2)-adrenoceptor antagonist idazoxan (0.1 μM) but not to the α(1)-adrenoceptor antagonist prazosin (10nM). Idazoxan and the α(2C)-adrenoceptor antagonist JP 1302 (0.5-1 μM) reduced H(2)O(2)-induced facilitation. H(2)O(2) induced facilitation of nerve-evoked contractions was abolished by the non-selective cation channel blocker SKF-96365 (10 μM), suggesting it depends on Ca(2+) influx. In conclusion, H(2)O(2)-induced increases in nerve-evoked contractions depended on an intact endothelium and were mediated by activating thromboxane A(2) receptors and by increasing the contribution of α(2)-adrenoceptors to these responses.

  2. Prevalência de pressão arterial elevada em crianças e adolescentes: revisão sistemática The prevalence of high arterial blood pressure in children and adolescents: a systematic review

    Directory of Open Access Journals (Sweden)

    Diego Giulliano Destro Christofaro

    2011-12-01

    Full Text Available OBJETIVOS: identificar as prevalências de pressão arterial elevada em crianças e adolescentes em estudos publicados nos últimos 30 anos. MÉTODOS: foi realizada uma busca nas seguintesbases de dados: Medline/PubMed, Lilacs, Web ofScience, Embase e Scielo entre os anos de 1980 e 2009. Foram incluídos estudos originais de prevalência de pressão arterial elevada ou hipertensão com tamanho amostral superior a 500sujeitos. RESULTADOS: a prevalência de pressão arterial elevada em crianças e adolescentes de 4 a 20 anos variou de 0,46% a 20,6%. As menores prevalências de pressão arterial elevada foram detectadas nos estudos em que a maior parte da amostra foi composta por crianças de 4 a 7 anos. Os protocolos mais utilizados na avaliação da pressão arterial foram o da Task Force e o do National High Blood Pressure Education Program. Ao todo 52,4% dos estudos utilizaram o método auscultatório para verificar a medida de pressão arterial e 47,6%, o método oscilométrico. CONCLUSÕES: apesar da grande discrepância dos valores de prevalência encontrados, ressalta-se ocrescimento da prevalência de pressão arterial elevada na população de crianças e adolescentes de diversas partes do mundo.OBJECTIVES: to identify the prevalence of high blood pressure in children and adolescents in studiespublished in the past 30 years. METHODS: a search was carried out in the Medline/PubMed, Lilacs, Web of Science, Embase and Scielo databases for articles published between 1980 and 2009. Articles were included if they were original studies of the prevalence of high arterial blood pressure or hypertension in a sample of more than 500 subjects. RESULTS: the prevalence of high blood pressure (in individuals aged between 4 and 20 years varied from 0.46% to 20.6%. The lower prevalence of high blood pressure was found in studies where the majority ofthe sample was aged between 4 and 7 years. Theprotocols most commonly used for evaluation of blood pressure

  3. Association of Inter-arm Blood Pressure Difference with Asymptomatic Intracranial and Extracranial Arterial Stenosis in Hypertension Patients

    Science.gov (United States)

    Wang, Yan; Zhang, Jin; Qian, Yuesheng; Tang, Xiaofeng; Ling, Huawei; Chen, Kemin; Li, Yan; Gao, Pingjin; Zhu, Dingliang

    2016-01-01

    Inter-arm blood pressure (BP) difference has been associated with ischemic stroke. Local atherosclerosis of stroke differ among vulnerable individuals, whereas intracranial arterial stenosis (ICAS) is more frequently affected Asians, and extracranial arterial stenosis (ECAS) is more prevalent among whites. We hereby sought to explore the association of inter-arm BP difference with ICAS and ECAS in stroke-free hypertensive patients in Chinese population. All the 885 subjects were evaluated of ICAS and ECAS through computerized tomographic angiography. Both arm BP was measured simultaneously by Vascular Profiler-1000 device. In the continuous study, ICAS was significantly associated with age, male, average brachial SBP, diabetes, anti-hypertensive treatment and inter-arm DBP difference. ECAS was associated with age, inter-arm SBP and LDL. In the categorical study, subjects with the top quartile of inter-arm DBP difference (≥4 mmHg) showed significantly higher risk of ICAS (OR = 2.109; 95% CI, 1.24–3.587). And the participants with the top quartile of inter-arm SBP difference (≥6 mmHg) showed significantly higher risk of ECAS (OR = 2.288; 95% CI, 1.309–3.998). In conclusion, we reported a diverse association of inter-arm SBP/DBP difference with the ICAS/ECAS. Inter-arm DBP difference might be the early symbol of ICAS in Chinese population, which need further verification in long-term cohort study. PMID:27412818

  4. Increased oxidative stress and severe arterial remodeling induced by permanent high-flow challenge in experimental pulmonary hypertension

    Directory of Open Access Journals (Sweden)

    Fadel Elie

    2011-09-01

    Full Text Available Abstract Background Involvement of inflammation in pulmonary hypertension (PH has previously been demonstrated and recently, immune-modulating dendritic cells (DCs infiltrating arterial lesions in patients suffering from idiopathic pulmonary arterial hypertension (IPAH and in experimental monocrotaline-induced PH have been reported. Occurrence of perivascular inflammatory cells could be linked to local increase of oxidative stress (OS, as it has been shown for systemic atherosclerosis. The impact of OS on vascular remodeling in PH is still to be determined. We hypothesized, that augmented blood-flow could increase OS and might thereby contribute to DC/inflammatory cell-recruitment and smooth-muscle-cell-proliferation. Methods We applied a monocrotaline-induced PH-model and combined it with permanent flow-challenge. Thirty Sprague-Dawley rats were assigned to following groups: control, monocrotaline-exposure (MCT, monocrotaline-exposure/pneumonectomy (MCT/PE. Results Hemodynamic exploration demonstrated most severe effects in MCT/PE, corresponding in histology to exuberant medial and adventitial remodeling of pulmonary muscular arteries, and intimal remodeling of smaller arterioles; lung-tissue PCR evidenced increased expression of DCs-specific fascin, CD68, proinflammatory cytokines (IL-6, RANTES, fractalkine in MCT/PE and to a lesser extent in MCT. Major OS enzyme NOX-4 was maximal in MCT/PE. Antioxidative stress enzymes Mn-SOD and glutathion-peroxidase-1 were significantly elevated, while HO-1 showed maximal expression in MCT with significant decrease in MCT/PE. Catalase was decreased in MCT and MCT/PE. Expression of NOX-4, but also of MN-SOD in MCT/PE was mainly attributed to a highly increased number of interstitial and perivascular CXCR4/SDF1 pathway-recruited mast-cells. Stress markers malonedialdehyde and nitrotyrosine were produced in endothelial cells, medial smooth muscle and perivascular leucocytes of hypertensive vasculature

  5. Exposure to bisphenol A from drinking canned beverages increases blood pressure: randomized crossover trial.

    Science.gov (United States)

    Bae, Sanghyuk; Hong, Yun-Chul

    2015-02-01

    Bisphenol A (BPA) is a chemical used in plastic bottles and inner coating of beverage cans, and its exposure is almost ubiquitous. BPA has been associated with hypertension and decreased heart rate variability in the previous studies. The aim of the present study was to determine whether increased BPA exposure from consumption of canned beverage actually affects blood pressure and heart rate variability. We conducted a randomized crossover trial with noninstitutionalized adults, who were aged ≥60 years and recruited from a local community center. A total of 60 participants visited the study site 3 times, and they were provided the same beverage in 2 glass bottles, 2 cans, or 1 can and 1 glass bottle at a time. The sequence of the beverage was randomized. We then measured urinary BPA concentration, blood pressure, and heart rate variability 2 hours after the consumption of each beverage. The paired t test and mixed model were used to compare the differences. The urinary BPA concentration increased after consuming canned beverages by >1600% compared with that after consuming glass bottled beverages. Systolic blood pressure adjusted for daily variance increased by ≈4.5 mm Hg after consuming 2 canned beverages compared with that after consuming 2 glass bottled beverages, and the difference was statistically significant. The parameters of the heart rate variability did not show statistically significant differences.The present study demonstrated that consuming canned beverage and consequent increase of BPA exposure increase blood pressure acutely.

  6. Artificial reproduction of magnetic fields produced by a natural geomagnetic storm increases systolic blood pressure in rats

    Science.gov (United States)

    Martínez-Bretón, J. L.; Mendoza, B.; Miranda-Anaya, M.; Durán, P.; Flores-Chávez, P. L.

    2016-04-01

    The incidence of geomagnetic storms may be associated with changes in circulatory physiology. The way in which the natural variations of the geomagnetic field due to solar activity affects the blood pressure are poorly understood and require further study in controlled experimental designs in animal models. In the present study, we tested whether the systolic arterial pressure (AP) in adult rats is affected by simulated magnetic fields resembling the natural changes of a geomagnetic storm. We exposed adult rats to a linear magnetic profile that simulates the average changes associated to some well-known geomagnetic storm phases: the sudden commencement and principal phase. Magnetic stimulus was provided by a coil inductor and regulated by a microcontroller. The experiments were conducted in the electromagnetically isolated environment of a semi-anechoic chamber. After exposure, AP was determined with a non-invasive method through the pulse on the rat's tail. Animals were used as their own control. Our results indicate that there was no statistically significant effect in AP when the artificial profile was applied, neither in the sudden commencement nor in the principal phases. However, during the experimental period, a natural geomagnetic storm occurred, and we did observe statistically significant AP increase during the sudden commencement phase. Furthermore, when this storm phase was artificially replicated with a non-linear profile, we noticed a 7 to 9 % increase of the rats' AP in relation to a reference value. We suggested that the changes in the geomagnetic field associated with a geomagnetic storm in its first day could produce a measurable and reproducible physiological response in AP.

  7. Artificial reproduction of magnetic fields produced by a natural geomagnetic storm increases systolic blood pressure in rats

    Science.gov (United States)

    Martínez-Bretón, J. L.; Mendoza, B.; Miranda-Anaya, M.; Durán, P.; Flores-Chávez, P. L.

    2016-11-01

    The incidence of geomagnetic storms may be associated with changes in circulatory physiology. The way in which the natural variations of the geomagnetic field due to solar activity affects the blood pressure are poorly understood and require further study in controlled experimental designs in animal models. In the present study, we tested whether the systolic arterial pressure (AP) in adult rats is affected by simulated magnetic fields resembling the natural changes of a geomagnetic storm. We exposed adult rats to a linear magnetic profile that simulates the average changes associated to some well-known geomagnetic storm phases: the sudden commencement and principal phase. Magnetic stimulus was provided by a coil inductor and regulated by a microcontroller. The experiments were conducted in the electromagnetically isolated environment of a semi-anechoic chamber. After exposure, AP was determined with a non-invasive method through the pulse on the rat's tail. Animals were used as their own control. Our results indicate that there was no statistically significant effect in AP when the artificial profile was applied, neither in the sudden commencement nor in the principal phases. However, during the experimental period, a natural geomagnetic storm occurred, and we did observe statistically significant AP increase during the sudden commencement phase. Furthermore, when this storm phase was artificially replicated with a non-linear profile, we noticed a 7 to 9 % increase of the rats' AP in relation to a reference value. We suggested that the changes in the geomagnetic field associated with a geomagnetic storm in its first day could produce a measurable and reproducible physiological response in AP.

  8. Liver cirrhosis and arterial hypertension

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Møller, Søren

    2006-01-01

    blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension (essential, secondary) may become normotensive during the development...... of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most......Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counter-regulatory systems (renin-angiotensin-aldosterone system, sympathetic nervous system, release...

  9. A comparison of the indirect estimate of mean arterial pressure calculated by the conventional equation and calculated to compensate for a change in heart rate.

    Science.gov (United States)

    Rogers, G; Oosthuyse, T

    2000-02-01

    The standard equation used to calculate mean arterial pressure (MAP) assumes that diastole persists for 2/3 and systole for 1/3 of each cardiac cycle. This ratio is altered when heart rate increases, and therefore we investigated the efficacy of predicting MAP during exercise using non-invasive indirect methods. Eight subjects exercised on a cycle ergometer for 3 minute intervals to elicit heart rates between 100-110, 120-130, 140-150, 160-170, and 180-190 beats/min. In the last minute of each 3 min interval an ECG recording was taken and systolic (SP) and diastolic (DP) blood pressure was measured by manual auscultation. MAP was calculated for each heart rate interval by: MAP=DP+1/3(SP-DP) (method A), and MAP= DP + Fs(SP- DP) (method B), where Fs is the fraction of the cardiac cycle comprising systole, measured from the ECG. Fs increased from 0.35+/-0.049 at rest to 0.47+/-0.039 at a heart rate of 180-190 beats/min. MAP measured by method B was consistently greater than MAP calculated by method A at all heart rates greater than resting heart rate (pequation (method A) to derive MAP during exercise (measured as the percentage difference between method A and B) increased linearly with heart rate (r=0.98). The standard MAP equation should not be applied during exercise, as it does not account for the change in the systolic: diastolic period ratio as heart rate increases.

  10. Transient pool boiling heat transfer due to increasing heat inputs in subcooled water at high pressures

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, K. [Kobe Univ. of Mercantile Marine (Japan); Shiotsu, M.; Sakurai, A. [Kyoto Univ. (Japan)

    1995-09-01

    Understanding of transient boiling phenomenon caused by increasing heat inputs in subcooled water at high pressures is necessary to predict correctly a severe accident due to a power burst in a water-cooled nuclear reactor. Transient maximum heat fluxes, q{sub max}, on a 1.2 mm diameter horizontal cylinder in a pool of saturated and subcooled water for exponential heat inputs, q{sub o}e{sup t/T}, with periods, {tau}, ranging from about 2 ms to 20 s at pressures from atmospheric up to 2063 kPa for water subcoolings from 0 to about 80 K were measured to obtain the extended data base to investigate the effect of high subcoolings on steady-state and transient maximum heat fluxes, q{sub max}. Two main mechanisms of q{sub max} exist depending on the exponential periods at low subcoolings. One is due to the time lag of the hydrodynamic instability which starts at steady-state maximum heat flux on fully developed nucleate boiling (FDNB), and the other is due to the heterogenous spontaneous nucleations (HSN) in flooded cavities which coexist with vapor bubbles growing up from active cavities. The shortest period corresponding to the maximum q{sub max} for long period range belonging to the former mechanism becomes longer and the q{sub max}mechanism for long period range shifts to that due the HSN on FDNB with the increase of subcooling and pressure. The longest period corresponding to the minimum q{sub max} for the short period range belonging to the latter mechanism becomes shorter with the increase in saturated pressure. On the contrary, the longest period becomes longer with the increase in subcooling at high pressures. Correlations for steady-state and transient maximum heat fluxes were presented for a wide range of pressure and subcooling.

  11. Reduced blood pressure of CFTR-F508del carriers correlates with diminished arterial reactivity rather than circulating blood volume in mice.

    Directory of Open Access Journals (Sweden)

    Veronica A Peotta

    Full Text Available The F508del mutation of the cystic fibrosis transmembrane conductance regulator (CFTR is the most common cause of cystic fibrosis (CF. Both CF patients and F508del carriers have de