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Author(s): Rhoda N. Ndanuko [sup.1] , Linda C. Tapsell [sup.1] , Karen E. Charlton [sup.1] , Elizabeth P. Neale [sup.1] , Marijka J. Batterham [sup.2] Author Affiliations: (1) School of [...], Background/objectives In addition to weight-loss, healthy dietary patterns and lower sodium intakes can help reduce blood pressure (BP), but individualised dietary advice may be necessary to achieve these effects. This study aimed to examine the impact of individualised dietary advice on BP in the intensive phase of a weight-loss trial. Subjects/methods Secondary analysis of baseline and 3-month data from the HealthTrack randomised controlled trial (n = 211). Participants were randomly assigned to one of three dietary advice groups: general advice (control), individualised advice (intervention group, I), or intervention group supplemented with 30 g walnuts/day (IW). Resting BP and 24-h urine sodium and potassium were measured. Dietary intake was evaluated through diet history interviews. Results Unadjusted SBP reduced significantly in all groups (IW and I groups P < 0.001; control group P = 0.002) and DBP in IW and I groups (P < 0.001). Compared to controls, the reductions in BP were 3-4 mmHg greater in the I and IW groups, but this only reached significance for DBP in the I group (-3.3 mmHg; P = 0.041). After controlling for age, sex, medication, weight-loss, physical activity and smoking, only the IW group showed a significant association between SBP reduction and increased urinary potassium ([beta] = -0.101, P = 0.044), decreased sodium:potassium ratio ([beta] = 2.446, P = 0.037) and increased consumption of seed and nut products and dishes ([beta] = -0.108, P = 0.034). Conclusions Dietary patterns with distinctive foods and lower sodium:potassium ratios may enhance the effects of weight-loss on BP. The patterns were best achieved with individualised dietary advice and food supplements.

ARTICLE INFO Keywords: Angelica dahurica Imperatorin (IMP) Oxidase stress NADPH oxidase 2K,1C hypertension ABSTRACT The 2-kidney, 1-clip (2K,1C) model of hypertension was used to investigate the potential antihypertensive and antioxidant [...]

INTRODUCTION Dietary factors affecting osteoporosis Although many factors that affect bone mineral density (BMD) are known, they account for only half of the variability among subjects when assessing risks for [...], BACKGROUND/OBJECTIVES: In vitro studies demonstrate that bone is degraded in an acidic environment due to chemical reactions and through effects on bone cells. Clinical evidence is insufficient to unequivocally resolve whether the diet net acid or base load bone affects breakdown in humans. Increasing dietary salt (sodium chloride, NaCl) mildly increases blood acidity in humans and in rats with increased sensitivity to the blood pressure effects of salt, whereas increased potassium (K) intake can decrease blood pressure. Blood pressure responses to NaCl or K may potentially be a marker for increased bone turnover or lower bone mineral density (BMD) in women at higher risk for osteoporosis and fracture. SUBJECTS/METHODS: We retrospectively analysed data from two data sets (California and NE Scotland) of postmenopausal women (n = 266) enrolled in long-term randomized, placebo-controlled studies of the effects of administration of low- or high-dose dietary K alkali supplementation on bone turnover in relation to sodium or chloride excretion (a marker of dietary salt intake). Mean arterial pressure (MAP) was calculated from blood pressure measures, MAP was divided into tertiles and its influence on the effect of dietary NaCl and K alkali supplementation on deoxypyridinoline markers of bone resorption and BMD by DEXA was tested. Data was analysed for each data set separately and then combined. RESULTS: Percentage change in BMD after 24 months was less for California compared with North East Scotland (hip: -0.6 ± 2.8% and -1.5 ± 2.4%, respectively (P = 0.027);spine: -0.5 ± 3.4% and -2.6 ± 3.5%, (P CONCLUSIONS: Blood pressure responses to Na, Cl or K intake did not help predict a BMD response to diet alkali therapy. European Journal of Clinical Nutrition (2012) 66, 1315-1322; doi: 10.1038/ejcn.2012.151; published online 24 October 2012 Keywords: osteoporosis; blood pressure; diet; potassium; sodium chloride

Caring for and managing an infant or a child with a chest drain may cause the children's nurse some anxiety because, although the management is relatively simple, there is potential [...]

A study was conducted to evaluate whether the addition of cardiac-resynchronization therapy (CRT) to an implantable cardioverter-defibrillator (ICD) was effective in reducing mortality and morbidity among patients with left ventricular systolic dysfunction and a wide QRS complex. Results indicated that in the case of such patients, the addition of CRT to ICD was quite effective in reducing the rates of mortality.

Dietary nitrate (N[O.sup.-.sub.3]) supplementation with beetroot juice (BR) over 4-6 days has been shown to reduce the [O.sub.2] cost of submaximal exercise and to improve exercise tolerance. However, it is not known whether shorter (or longer) periods of supplementation have similar (or greater) effects. We therefore investigated the effects of acute and chronic N[O.sup.-.sub.3] supplementation on resting blood pressure (BP) and the physiological responses to moderate-intensity exercise and ramp incremental cycle exercise in eight healthy subjects. Following baseline tests, the subjects were assigned in a balanced crossover design to receive BR (0.5 l/day; 5.2 mmol of N[O.sup.-.sub.3]/day) and placebo (PL; 0.5 l/day low-calorie juice cordial) treatments. The exercise protocol (two moderate-intensity step tests followed by a ramp test) was repeated 2.5 h following first ingestion (0.5 liter) and after 5 and 15 days of BR and PL. Plasma nitrite concentration (baseline: 454 [+ or -] 81 nM) was significantly elevated (+39% at 2.5 h postingestion; +25% at 5 days; +46% at 15 days; P < 0.05) and systolic and diastolic BP (baseline: 127 [+ or -] 6 and 72 [+ or -] 5 mmHg, respectively) were reduced by ~4% throughout the BR supplementation period (P < 0.05). Compared with PL, the steady-state [??][O.sub.2] during moderate exercise was reduced by ~4% after 2.5 h and remained similarly reduced after 5 and 15 days of BR (P < 0.05). The ramp test peak power and the work rate at the gas exchange threshold (baseline: 322 [+ or -] 67 W and 89 [+ or -] 15 W, respectively) were elevated after 15 days of BR (331 [+ or -] 68 W and 105 [+ or -] 28 W; P < 0.05) but not PL (323 [+ or -] 68 W and 84 [+ or -] 18 W). These results indicate that dietary N[O.sup.-.sub.3] supplementation acutely reduces BP and the [O.sub.2] cost of submaximal exercise and that these effects are maintained for at least 15 days if supplementation is continued. beetroot juice; [O.sub.2] uptake; ramp exercise; performance; nitric oxide doi: 10.1152/ajpregu.00206.2010.

The present study was designed to document changes in sympathetic nerve activity and cardiovascular function when conscious rats were challenged with a noise stressor to induce freezing behavior. The potential contribution of the arterial baroreceptors in regulating sympathetic nerve activity and cardiovascular adjustments during the freezing behavior was then examined. Wistar male rats were assigned to sham-operated (SO) and sinoaortic-denervated (SAD) groups and instrumented chronically with electrodes for measurements of renal (RSNA) and lumbar (LSNA) sympathetic nerve activity, electroencephalogram, electromyogram, and electrocardiogram and catheters for measurements of systemic arterial and central venous pressure. Both SO and SAD rats were exposed to 90 dB of white noise for l0 min, causing freezing behavior in both groups. In SO rats, freezing behavior was associated with an immediate and significant (P < 0.05) increase in RSNA, no changes in LSNA or mean arterial pressure, and a significant (P < 0.05) decrease in heart rate. SAD attenuated the magnitude of the immediate increase in RSNA and had no influence on the response in LSNA during freezing behavior compared with SO rats. Moreover, in SAD rats, mean arterial pressure increased significantly (P < 0.05) while heart rate did not change during the freezing behavior. These data indicate that freezing behavior evokes regionally different changes in sympathetic outflows, which may be involved in generating the patterned responses of cardiovascular function to stressful or threatening sensory stimulation. Moreover, it is suggested that the arterial baroreceptors are involved in generating the differential changes in RSNA and LSNA and thus the patterned changes in cardiovascular functions observed during freezing behavior in conscious rats. arterial pressure; baroreceptors; cardiovascular regulation doi: 10.1152/ajpregu.00831.2009.

The study aims to evaluate the association between intensive blood pressure control and a reduction in progression of African-American patients with hypertensive chronic kidney disease. The results indicate that such control had no effect on progression of the disease; however, there were differential effects.

Following sinoaortic denervation, which eliminates arterial baroreceptor input into the brain, there are slowly developing adaptations that abolish initial sympathetic activation and hypertension. In comparison, electrical stimulation of the carotid sinus for 1 wk produces sustained reductions in sympathetic activity and arterial pressure. However, whether compensations occur subsequently to diminish these responses is unclear. Therefore, we determined whether there are important central and/or peripheral adaptations that diminish the sympathoinhibitory and blood pressure-lowering effects of more sustained carotid sinus stimulation. To this end, we measured whole body plasma norepinephrine spillover and [[alpha].sub.1]-adrenergic vascular reactivity in six dogs over a 3-wk period of baroreflex activation. During the first week of baroreflex activation, there was an ~45% decrease in plasma norepinephrine spillover, along with reductions in mean arterial pressure and heart rate of ~20 mmHg and 15 beats/min, respectively; additionally, plasma renin activity did not increase. Most importantly, these responses during week 1 were largely sustained throughout the 3 wk of baroreflex activation. Acute pressor responses to [alpha]-adrenergic stimulation during ganglionic blockade were similar throughout the study, indicating no compensatory increases in adrenergic vascular reactivity. These findings indicate that the sympathoinhibition and lowering of blood pressure and heart rate induced by chronic activation of the carotid baroreflex are not diminished by adaptations in the brain and peripheral circulation. Furthermore, by providing evidence that baroreflexes have long-term effects on sympathetic activity and arterial pressure, they present a perspective that is opposite from studies of sinoaortic denervation. blood pressure: sympathetic nervous system; renin-angiotensin system doi: 10.1152/ajpheart.00372.2010.

Obesity is a risk factor for stroke, but the determinants of increased stroke risk in obesity are unknown. We have previously reported that obese Zucker rats (OZRs) have a worse stroke outcome and display evidence of remodeling of the middle cerebral artery (MCA), in parallel with hypertension, compared with lean controls. This study tested the hypothesis that hypertension is an essential determinant of cerebral vascular remodeling and increased stroke damage in OZRs. Blood pressure was measured by telemetery in lean and obese rats with and without hydrochlorthiazide (HCT; 2 mg x [kg.sup.-1] x [day.sup.-1]) from 8 to 15 wk of age. A separate group of rats was also chronically fed a low-sodium (LS) diet. Vessel structure was assessed in isolated, pressurized MCAs. Cerebral ischemia was induced for 60 rain using an intralumenal suture technique, followed by 24 h of reperfusion. HCT treatment effectively prevented the increase in blood pressure in obese rats; however, the LS diet did not lower pressure. Importantly, infarct size was normalized by HCT after ischemia-reperfusion injury. Additionally, HCT improved the changes in MCA structure observed in untreated OZRs. There were no benefits of the LS diet on stroke injury or vessel structure. These results indicate that increased pressure is essential for driving the changes in infarct size in OZRs. hypertension; vascular remodeling; hydrochlorothiazide doi: 10.1152/ajpheart.01111.2009.

Background. In contrast to middle age, higher body mass index (BMI), cholesterol levels, and blood pressures associate no longer with increased mortality in old age. With increasing age, these risk factors are prone to change over time. It is unclear whether dynamics of these traditional metabolic risk factors in late life associate with mortality and whether they occur in concert with each other. Methods. Within the Leiden 85-plus Study, a prospective population-based study of 599 participants aged 85 years, participants were annually assessed during a 5-year follow-up period and observed for mortality for 10 years. Results. BMI, total cholesterol levels, glucose levels, and blood pressures declined and HDL cholesterol levels increased between ages 85 and 90 years (all p < .005). Participants who died at age 90 years had stronger annual declines in BMI, total cholesterol levels, and diastolic blood pressure and weaker increases in HDL cholesterol levels than participants who survived until the end of follow-up (all p [less than or equal to] .001). In a principal component analysis, annual changes in total, LDL, and HDL cholesterol levels; blood pressures; and glucose, albumin, hemoglobin, leukocyte, and C-reactive protein levels grouped together in one component (all correlation r with component >.40), which associated with allcause and cancer mortality. Conclusions. In old age, larger declines in BMI, total cholesterol levels, and blood pressures and weaker increases in HDL cholesterol levels associate with mortality. We identified distinct clustering in the dynamics of these traditional metabolic risk factors and indicators of health and disease in a profile that is suggestive of underlying wasting disease. Key Words: Mortality--Risk factors--Longitudinal changes--Old age. doi: 10.1093/gerona/glq014

Renin, an aspartyl protease that catalyzes the rate-limiting step in the renin-angiotensin system (RAS), is proteolytically activated by a second protease [referred to as the prorenin processing enzyme (PPE)] before its secretion from the juxtaglomerular cells of the kidney. Although several enzymes are capable of activating renin in vitro, the leading candidate for the PPE in the kidney is cathepsin B (CTSB) due to is colocalization with the renin precursor (prorenin) in juxtaglomerular cell granules and because of its site-selective activation of human prorenin both in vitro and in transfected tissue culture cell models. To verify the role of CTSB in prorenin processing in vivo, we tested the ability of CTSB-deficient (CTSB-/-) mice to generate active renin. CTSB-/- mice do not exhibit any overt symptoms (renal malformation, preweaning mortality) typical of an RAS deficiency and have normal levels of circulating active renin, which, like those in control animals, rise more than 15-fold in response to pharmacologic inhibition of the RAS. The mature renin enzyme detected in kidney lysates of CTSB-/- mice migrates at the same apparent molecular weight as that in control mice, and the processing to active renin is not affected by chloroquine treatment of the animals. Finally, the distribution and morphology of renin-producing cells in the kidney is normal in CTSB-/- mice. In conclusion, CTSB-deficient mice exhibit no differences compared with controls in their ability to generate active renin, and our results do not support CTSB as the PPE in mice. blood pressure; renin-angiotensin system; renin; enzyme precursor; mouse knock out doi: 10.1152/ajpregu.00830.2009.

Respiratory sinus arrhythmia (RSA) is classically described as a vagally mediated increase and decrease in heart rate concurrent with inspiration and expiration, respectively. However, although breathing frequency is known to alter this temporal relationship, the precise nature of this phase dependency and its relationship to blood pressure remains unclear. In 16 subjects we systematically examined the temporal relationships between respiration, RSA, and blood pressure by graphically portraying cardiac interval (R-R) and systolic blood pressure (SBP) variations as a function of the respiratory cycle (pattern analysis), during incremental stepwise paced breathing. The principal findings were 1) the time interval between R-R maximum and expiration onset remained the same (~2.5-3.0 s) irrespective of breathing frequency (P = 0.10), whereas R-R minimum progressively shifted from expiratory onset into midinspiration with slower breathing (P < 0.0001); 2) there is a clear qualitative distinction between pre- versus postinspiratory cardiac acceleration during slow (0.10 Hz) but not fast (0.20 Hz) breathing; 3) the time interval from inspiration onset to SBP minimum (P = 0.16) and from expiration onset to SBP maximum (P = 0.26) remained unchanged across breathing frequencies; 4) SBP maximum and R-R maximum maintained an unchanged temporal alignment of ~1.1 s irrespective of breathing frequency (P = 0.84), whereas the alignment between SBP minimum and R-R minimum was inconstant (P > 0.0001); and 5) [beta].sub.1]-adrenergic blockade did not influence the respiration-RSA relationships or distinct RSA patterns observed during slow breathing, suggesting that temporal dependencies associated with alterations in breathing frequency are unrelated to cardiac sympathetic modulation. Collectively, these results illustrate nonlinear respiration-RSA-blood pressure relationships that may yield new insights to the fundamental mechanism of RSA in humans. autonomic nervous system; vagal; sympathetic; blood pressure doi: 10.1152/ajpheart.00036.2010.

Author(s): Alexander D. Cornet [sup.1], Jorrit J. Hofstra [sup.2] [sup.3], Eleonora L. Swart [sup.4], Armand R. J. Girbes [sup.1], Nicole P. Juffermans [sup.2] Author Affiliations: (1) grid.16872.3a, 000000040435165X, Department of [...], Objective Pulmonary hypertension is a characteristic feature of acute respiratory distress syndrome (ARDS) and contributes to mortality. Administration of sildenafil in ambulatory patients with pulmonary hypertension improves oxygenation and ameliorates pulmonary hypertension. Our aim was to determine whether sildenafil is beneficial for patients with ARDS. Design Prospective, open-label, multicenter, interventional cohort study. Setting Medical-surgical ICU of two university hospitals. Patients Ten consecutive patients meeting the NAECC criteria for ARDS. Interventions A single dose of 50 mg sildenafil citrate administered via a nasogastric tube. Main results Administration of sildenafil in patients with ARDS decreased mean pulmonary arterial pressure from 25 to 22 mmHg (P = 0.022) and pulmonary artery occlusion pressure from 16 to 13 mmHg (P = 0.049). Systemic mean arterial pressures were markedly decreased from 81 to 75 mmHg (P = 0.005). Sildenafil did not improve pulmonary arterial oxygen tension, but resulted in a further increase in the shunt fraction. Conclusion Although sildenafil reduced pulmonary arterial pressures during ARDS, the increased shunt fraction and decreased arterial oxygenation render it unsuitable for the treatment of patients with ARDS.

The study aims to investigate whether therapy for reducing normal systolic pressure i.e.

Author(s): Asthildur Erlingsdottir [sup.1] , Olafur S. Indridason [sup.2] , Olafur Thorvaldsson [sup.3] , Vidar O. Edvardsson [sup.1] [sup.4] Author Affiliations: (1) grid.14013.37, 0000000406400021, Faculty of Medicine, University of Iceland, [...], The aim of this study was to examine the association between blood pressure (BP) in children and adolescents and cardiovascular and renal disease in adulthood. This was a retrospective study on patients

The article reviews the use of thiazide diuretics, which are commonly indicated for long-term therapy for hypertension. It also examines the use of loop diuretics and potassium-sparing agents.

The study evaluates the long-term renoprotective effect of intensified blood-pressure control among children with chronic kidney disease receiving a fixed high dose of an angiotensin-converting-enzyme (ACE) inhibitor. Evidence indicates intensified blood-pressure control, with target 24-hour blood-pressure levels in the low range of normal, offers a significant benefit to renal function among children.

The sympathetic nervous system plays a key role in regulating arterial blood pressure in humans. This review provides an overview of sympathetic neural control of the circulation and discusses the [...]

Byline: Martin W. Dunser (1), Jukka Takala (1), Hanno Ulmer (2), Viktoria D. Mayr (3), Gunter Luckner (3), Stefan Jochberger (3), Fritz Daudel (1), Philipp Lepper (1), Walter R. Hasibeder (4), Stephan M. Jakob (1) Keywords: Hypotension; Mean arterial blood pressure; Mean perfusion pressure; Sepsis Abstract: Objective To evaluate the association between arterial blood pressure (ABP) during the first 24 h and mortality in sepsis. Design Retrospective cohort study. Setting Multidisciplinary intensive care unit (ICU). Patients and participants A total of 274 septic patients. Interventions None. Measurements and results Hemodynamic, and laboratory parameters were extracted from a PDMS database. The hourly time integral of ABP drops below clinically relevant systolic arterial pressure (SAP), mean arterial pressure (MAP), and mean perfusion pressure (MPP = MAP - central venous pressure) levels was calculated for the first 24 h after ICU admission and compared with 28-day-mortality. Binary and linear regression models (adjusted for SAPS II as a measure of disease severity), and a receiver operating characteristic (ROC) analysis were applied. The areas under the ROC curve were largest for the hourly time integrals of ABP drops below MAP 60 mmHg (0.779 vs. 0.764 for ABP drops below MAP 55 mmHg P a$? 0.01) and MPP 45 mmHg. No association between the hourly time integrals of ABP drops below certain SAP levels and mortality was detected. One or more episodes of MAP < 60 mmHg increased the risk of death by 2.96 (CI 95%, 1.06--10.36, P = 0.04). The area under the ROC curve to predict the need for renal replacement therapy was highest for the hourly time integral of ABP drops below MAP 75 mmHg. Conclusions A MAP level aY= 60 mmHg may be as safe as higher MAP levels during the first 24 h of ICU therapy in septic patients. A higher MAP may be required to maintain kidney function. Author Affiliation: (1) Department of Intensive Care Medicine, Inselspital, 3010, Bern, Switzerland (2) Institute of Medical Biostatistics, Innsbruck Medical University, Innsbruck, Austria (3) Department of Anesthesiology and Critical Care Medicine, Innsbruck Medical University, Innsbruck, Austria (4) Department of Anesthesiology and Critical Care Medicine, Krankenhaus Ried im Innkreis, Ried im Innkreis, Austria Article History: Registration Date: 22/01/2009 Received Date: 29/05/2008 Accepted Date: 19/01/2009 Online Date: 03/02/2009 Article note: Electronic supplementary material The online version of this article (doi: 10.1007/s00134-009-1427-2) contains supplementary material, which is available to authorized users.

Byline: B. L. Keulenaer (1), J. J. Waele (2), B. Powell (1), M. L. N. G. Malbrain (3) Keywords: Intra-abdominal hypertension; Abdominal compartment syndrome; Body positioning; Prone positioning; PEEP and ARDS Abstract: Purpose To describe what is defined as normal intra-abdominal pressure (IAP) and how body positioning, body mass index (BMI) and positive end-expiratory pressure (PEEP) affect IAP monitoring. Methods A review of different databases was made (Pubmed, MEDLINE (January 1966--June 2007) and EMBASE.com (January 1966--June 2007)) using the search terms of 'IAP', 'intra-abdominal hypertension' (IAH), 'abdominal compartment syndrome' (ACS), 'body positioning', 'prone positioning', 'PEEP' and 'acute respiratory distress syndrome' (ARDS). Prior to 1966, we selected older articles by looking at the reference lists displayed in the more recent papers. Results This review focuses on the concept that the abdomen truly behaves as a hydraulic system. The definitions of a normal IAP in the general patient population and morbidly obese patients are reviewed. Subsequently, factors that affect the accuracy of IAP monitoring, i.e., body position (head of bed elevation, lateral decubitus and prone position) and PEEP, are explored. Conclusion The abdomen behaves as a hydraulic system with a normal IAP of about 5--7 mmHg, and with higher baseline levels in morbidly obese patients of about 9--14 mmHg. Measuring IAP via the bladder in the supine position is still the accepted standard method, but in patients in the semi-recumbent position (head of the bed elevated to 30deg and 45deg), the IAP on average is 4 and 9 mmHg, respectively, higher. Future research should be focused on developing and validating predictive equations to correct for supine IAP towards the semi-recumbent position. Small increases in IAP in stable patients without IAH, turned prone, have no detrimental effects. The role of prone positioning in the unstable patient with or without IAH still needs to be established. Author Affiliation: (1) Intensive Care Unit, Fremantle Hospital, Alma Street, Fremantle, WA, 6160, Australia (2) Intensive Care Unit, Ghent University Hospital, Ghent, Belgium (3) Department of Intensive Care Medicine, Ziekenhuis Netwerk Antwerpen (ZNA), Stuivenberg, Antwerp, Belgium Article History: Registration Date: 10/02/2009 Received Date: 10/11/2008 Accepted Date: 06/02/2009 Online Date: 26/02/2009

This study tested the hypothesis that passive heating impairs cerebral autoregulation. Transfer function analyses of resting arterial blood pressure and middle cerebral artery blood velocity (MCA [V.sub.mean]), as well as MCA [V.sub.mean] and blood pressure responses to rapid deflation of previously inflated thigh cuffs, were examined in nine healthy subjects under normothermic and passive heat stress (increase core temperature 1.1 [+ or -] 0.2[degrees]C, P < 0.001) conditions. Passive heating reduced MCA [V.sub.mean] [change ([DELTA]) of 8 [+ or -] 8 cm/s, P = 0.01], while blood pressure was maintained ([DELTA] - 1 [+ or -] 4 mmHg, P = 0.36). Coherence was decreased in the very-low-frequency range during heat stress (0.57 [+ or -] 0.13 to 0.26 [+ or -] 0.10, P = 0.001), but was >0.5 and similar between normothermia and heat stress in the low- (0.07-0.20 Hz, P = 0.40) and high-frequency (0.20-0.35 Hz, P = 0.12) ranges. Transfer gain was reduced during heat stress in the very-low-frequency (0.88 [+ or -] 0.38 to 0.59 [+ or -] 0.19 cm x [s.sup.-1] x [mmHg.sup.-1], P = 0.02) range, but was unaffected in the low-and high-frequency ranges. The magnitude of the decrease in blood pressure (normothermia: 20 [+ or -] 4 mmHg, heat stress: 19 [+ or -] 6 mmHg, P = 0.88) and MCA [V.sub.mean] (13 [+ or -] 4 to 12 [+ or -] 6 cm/s, P = 0.59) in response to cuff deflation was not affected by the thermal condition. Similarly, the rate of regulation of cerebrovascular conductance (CBVC) after cuff release (0.44 [+ or -] 0.22 to 0.38 [+ or -] 0.13 [DELTA]CBVC units/s, P = 0.16) and the time for MCA [V.sub.mean] to recover to precuff deflation baseline (10.0 [+ or -] 7.9 to 8.7 [+ or -] 4.9 s, P = 0.77) were not affected by heat stress. Counter to the proposed hypothesis, similar rate of regulation responses suggests that heat stress does not impair the ability to control cerebral perfusion after a rapid reduction in perfusion pressure, while reduced transfer function gain and coherence in the very-low-frequency range during heat stress suggest that dynamic cerebral autoregulation is improved during spontaneous oscillations in blood pressure within this frequency range. brain blood flow; heating; transfer function; blood pressure

Background. To examine the association between sleep-disordered breathing (SDB) and 24-hour blood pressure (BP) pattern among community-dwelling older adults. Methods. A convenience sample of 70 community-dwelling older adults, recruited from senior housing, community centers, and learning centers, were admitted to General Clinical Research Center, Emory University Hospital, Atlanta, Ga. Information regarding demographic and clinical history was obtained using questionnaires. Twenty-four-hour BP monitoring in supine position was performed using Spacelabs model 20207. Breathing during sleep was monitored with the use of a modified sleep recording system (Embletta, PDS), which monitors nasal and oral airflow, chest and abdominal movements, and pulse oximetry. Night time-daytime (night-day) BP ratio (average night-time BP divided by daytime BP) was calculated both for systolic and diastolic BPs. Results. Sixty-nine participants, mean age 74.9 [+ or -] 6.4 years (41 [57%] women), completed the study. The mean apnea-hypopnea index (AHI) was 13 [+ or -] 13 per hour of sleep, and 20 participants (29%) had AHI [greater than or equal to] 15 per hour of sleep, indicating moderate to severe SDB. Moderate to severe SDB (AHI [greater than or equal to] 15 per hour of sleep) was significantly associated with nocturnal hypertension, whereas there was no statistically significant difference in wake-time BP between those with and without moderate to severe SDB. Stepwise multiple regressions showed that AHI independently predicted increased night-day systolic and night-day diastolic BP ratio, even after controlling for nocturia frequency. Conclusions. The results indicate increased BP load associated with increased AHI in this group of older adults. This increased BP load may contribute to increased hypertension-related morbidity and disease burden. Key Words: Sleep-Disordered breathing--24-hour BP pattern.

Byline: Manuel Ignacio Monge Garcia (1), Anselmo Gil Cano (1), Juan Carlos Diaz Monrove (1) Keywords: Valsalva maneuver; Fluid responsiveness; Arterial pressure; Cardiac output; Cardiac preload; Spontaneous breathing Abstract: Objective To evaluate whether arterial pressure response during a Valsalva maneuver could predict fluid responsiveness in spontaneously breathing patients. Design and setting Prospective clinical study in a 17-bed multidisciplinary intensive care unit. Patients Thirty patients without mechanical ventilation and equipped with a radial arterial catheter for whom the decision to give fluids was taken due to suspected hypovolemia. Intervention A 10-s Valsalva maneuver was performed before and after volume expansion (VE). Patients were classified as responders if stroke volume index (SVi) increased aY=15% after VE. Measurements and results Pulse pressure changes during the Valsalva maneuver (aVPP) were calculated as the difference between maximal pulse pressure during phase 1 and minimal pulse pressure during phase 2 of the Valsalva maneuver divided by the mean of the two values and expressed as a percentage. Valsalva changes in systolic pressure (aVSP) were calculated in similar way. SVi changes induced by VE was correlated with baseline values of aVPP and aVSP (r .sup.2 = 0.71 and r .sup.2 = 0.60 P < 0.0001, respectively), and with VE-induced changes in aVPP and aVSP (r .sup.2 = 0.56 and r .sup.2 = 0.44 P < 0.0001 and P < 0.001, respectively). A aVPP value of 52% and aVSP of 30% predicted fluid responsiveness with a sensitivity of 91% and 73% and a specificity of 95 and 90%, respectively. Conclusions Arterial response during the Valsalva maneuver is a feasible tool for predicting fluid responsiveness in patients without mechanical ventilatory support. Author Affiliation: (1) Servicio de Cuidados Criticos y Urgencias, Unidad de Investigacion Experimental, Hospital del SAS Jerez, C/ Circunvalacion s/n, 11407, Jerez de la Frontera, Spain Article History: Registration Date: 03/09/2008 Received Date: 18/04/2008 Accepted Date: 29/08/2008 Online Date: 02/10/2008 Article note: This article is discussed in the editorial available at: doi: 10.1007/s00134-008-1294-2. Electronic supplementary material The online version of this article (doi: 10.1007/s00134-008-1295-1) contains supplementary material, which is available to authorized users.

Introduction Cardiovascular disease (CVD) is a leading cause of death worldwide, contributing to 17.7 million deaths in 2015 (WHO 2017). Many epidemiological studies have shown that long-term exposure to particulate [...], Background: Long-term exposure to particulate matter (PM) air pollution may increase blood pressure and the risk of hypertension. However, epidemiological evidence is scarce and inconsistent. Objectives: We investigated the associations between long-term exposure to PM with an aerodynamic diameter Methods: We studied 361,560 adults [greater than or equal to]18 y old from a large cohort who participated in a standard medical examination program during 2001 to 2014. Among this group, 125,913 nonhypertensive participants were followed up. A satellite-based spatiotemporal model was used to estimate the 2-y average P[M.sub.2.5] concentrations at each participant&apos;s address. Multivariable linear regression was used in the cross-sectional data analysis with the 361,560 participants to investigate the associations between P[M.sub.2.5] and systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP), and Cox proportional hazard regression was used in the cohort data analysis with the 125,913 participants to investigate the associations between P[M.sub.2.5] and incident hypertension. Results: Each 10-[micro]g/[m.sup.3] increment in the 2-y average P[M.sub.2.5] concentration was associated with increases of 0.45 mmHg [95% confidence interval (CI): 0.40, 0.50], 0.07 mmHg (95% CI: 0.04, 0.11), and 0.38 mmHg (95% CI: 0.33, 0.42) in SBP, DBP, and PP, respectively, after adjusting for a wide range of covariates and possible confounders. Each 10-[micro]g/[m.sup.3] increment in the 2-y average P[M.sub.2.5] concentration was associated with an increase of 3% in the risk of developing hypertension [hazard ratio = 1.03 (95% CI: 1.01, 1.05)]. Stratified and sensitivity analyses yielded similar results. Conclusions: Long-term exposure to P[M.sub.2.5] air pollution is associated with higher blood pressure and an increased risk of hypertension. These findings reinforce the importance of air pollution mitigation strategies to reduce the risk of cardiovascular disease. https://doi.org/10.1289/EHP2466

Research on societal determinants of health suggests the existence of an 'inverse hazard law,' which we define as: 'The accumulation of health hazards tends to vary inversely with the power and resources of the populations affected.' Yet, little empirical research has systematically investigated this topic, including in relation to workplace exposures. We accordingly designed the United for Health study (Greater Boston Area, Massachusetts, 2003-2004) to investigate the joint distribution and health implications of workplace occupational hazards (dust, fumes, chemical, noise, ergonomic strain) and social hazards (racial discrimination, sexual harassment, workplace abuse). Focusing on blood pressure as our health outcome, we found that among the 1202 low-income multi-racial/ethnic working class participants in our cohort--of whom 40% lived below the US poverty line 79% reported exposure to at least one social hazard and 82% to at least one high- exposure occupational hazard. Only sexual harassment, the least common social hazard, was associated with elevated systolic blood pressure (SBP) among the women workers. By contrast, no statistically significant associations were detectable between the other additional highly prevalent social and occupational hazards and SBP; we did, however, find suggestive evidence of an association between SBP and response to unfair treatment, implying that in a context of high exposure, differential susceptibility to the exposure matters. These results interestingly contrast to our prior findings for this same cohort, in which we found associations between self-reported experiences of racial discrimination and two other health outcomes: psychological distress and cigarette smoking. Likely explanations for these contrasting findings include: (a) the differential etiologic periods and pathways involving somatic health, mental health, and health behaviors, and (b) the high prevalence of adverse exposures, limiting the ability to detect significant associations. As clarified by the 'inverse hazard law,' to understand health inequities, research is needed that contrasts exposures and health status population-wide, not just among those most inequitably exposed. Keywords: Blood pressure Health inequities Occupational health Racial discrimination Sexual harassment Workplace abuse USA

Byline: John A. Myburgh (1), Alisa Higgins (2), Alina Jovanovska (1), Jeffrey Lipman (3), Naresh Ramakrishnan (4), John Santamaria (5) Keywords: Epinephrine; Norepinephrine; Adrenaline; Noradrenaline; Shock; Sepsis Abstract: Objective To determine whether there was a difference between epinephrine and norepinephrine in achieving a mean arterial pressure (MAP) goal in intensive care (ICU) patients. Design Prospective, double-blind, randomised-controlled trial. Setting Four Australian university-affiliated multidisciplinary ICUs. Patients and participants Patients who required vasopressors for any cause at randomisation. Patients with septic shock and acute circulatory failure were analysed separately. Interventions Blinded infusions of epinephrine or norepinephrine to achieve a MAP aY=70 mmHg for the duration of ICU admission. Measurements Primary outcome was achievement of MAP goal >24 h without vasopressors. Secondary outcomes were 28 and 90-day mortality. Two hundred and eighty patients were randomised to receive either epinephrine or norepinephrine. Median time to achieve the MAP goal was 35.1 h (interquartile range (IQR) 13.8--70.4 h) with epinephrine compared to 40.0 h (IQR 14.5--120 h) with norepinephrine (relative risk (RR) 0.88 95% confidence interval (CI) 0.69--1.12 P = 0.26). There was no difference in the time to achieve MAP goals in the subgroups of patients with severe sepsis (n = 158 RR 0.81 95% CI 0.59--1.12 P = 0.18) or those with acute circulatory failure (n = 192 RR 0.89 95% CI 0.62--1.27 P = 0.49) between epinephrine and norepinephrine. Epinephrine was associated with the development of significant but transient metabolic effects that prompted the withdrawal of 18/139 (12.9%) patients from the study by attending clinicians. There was no difference in 28 and 90-day mortality. Conclusions Despite the development of potential drug-related effects with epinephrine, there was no difference in the achievement of a MAP goal between epinephrine and norepinephrine in a heterogenous population of ICU patients. Author Affiliation: (1) Department of Intensive Care Medicine, The St George Hospital, Gray Street, Kogarah, Sydney, 2217, Australia (2) Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, Australia (3) Department of Intensive Care Medicine, Royal Brisbane Hospital and University of Queensland, Brisbane, Australia (4) Intensive Therapy Unit, Royal North Shore Hospital, Sydney, Australia (5) Department of Intensive Care Medicine, St Vincent's Hospital, Melbourne, Australia Article History: Registration Date: 09/07/2008 Received Date: 01/01/2008 Accepted Date: 19/06/2008 Online Date: 25/07/2008 Article note: This study was presented at the Annual Congress of the European Society of Intensive Care Medicine in Berlin on October 10 2007. The presentation received the International Sepsis Forum prize for best abstract and paper. This study has been published in abstract form: Myburgh J.A., Higgins A., Jovanovska A., Lipman J., Ramakrishnan N., Santamaria J and the CAT Study Investigators. (2007). A comparison of epinephrine and norepinephrine on reversal of shock. Intensive Care Medicine 33 (Supplement 2): S197. Trial registration: The study was registered with Current Controlled Studies: ISRCTN number 92846592.

In this study, we examined the relationship between within-person blood pressure and cognitive functioning. We conducted an analysis on 36 community-dwelling elderly individuals (age range = 60-87 years). Participants measured their blood pressure and completed cognitive tasks (i.e., the Rey Auditory Verbal Learning Task, the Letter Series test, and the Number Comparison test) twice a day over 60 consecutive days. We observed a significant interaction between within-person change in blood pressure and average blood pressure for the Letter Series test. Individuals with high blood pressure tended to perform poorly, particularly on occasions when their blood pressure level was above their personal average. These results demonstrate that the relationship between blood pressure and cognition at the between-person level and the relationship within each individual should be further explored simultaneously. Key Words: Blood pressure--Cognition--Variability--Aging.

A study was conducted to monitor patients in the United Kingdom with Type 2 diabetes and blood pressure and determine whether tight blood pressure control reduced risks of microvascular and macrovascular disease. Results indicated that tight blood pressure control did help improve diabetes and quality of life if sustained for a long period.

The study examines if the low ankle brachial index (ABI) adequately predicts the risk of cardiovascular events and mortality independently of the Framingham risk score (FRS). Findings indicate that measurement of the ABI could improve the accuracy of cardiovascular prediction separately from the FRS.

It is well known that environmental stimulation is important for the proper development of sensory function. The vestibular system senses gravitational acceleration and then alters cardiovascular and motor functions through reflex path-ways. The development of vestibular-mediated cardiovascular and motor functions may depend on the gravitational environment present at birth and during subsequent growth. To examine this hypothesis, arterial pressure (AP) and renal sympathetic nerve activity (RSNA) were monitored during horizontal linear acceleration and performance in a motor coordination task in rats born and reared in 1-G or 2-G environments. Linear acceleration of [+ or -] 1 G increased AP and RSNA. These responses were attenuated in rats with a vestibular lesion, suggesting that the vestibular system mediated AP and RSNA responses. These responses were also attenuated in rats born in a 2-G environment. AP and RSNA responses were partially restored in these rats when the hypergravity load was removed, and the rats were maintained in a 1-G environment for 1 wk. The AP response to compressed air, which is mediated independently of the vestibular system, did not change in the 2-G environment. Motor coordination was also impaired in the 2-G environment and remained impaired even after 1 wk of unloading. These results indicate that hypergravity impaired both the vestibulo-cardiovascular reflex and motor coordination. The vestibulo-cardiovascular reflex was only impaired temporarily and partially recovered following 1 wk of unloading. In contrast, motor coordination did not return to normal in response to unloading. vestibular system; renal sympathetic nerve activity; arterial pressure; rotarod; linear acceleration