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  1. Oscillometric measurement of systolic and diastolic blood pressures validated in a physiologic mathematical model

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    Babbs Charles F

    2012-08-01

    Full Text Available Abstract Background The oscillometric method of measuring blood pressure with an automated cuff yields valid estimates of mean pressure but questionable estimates of systolic and diastolic pressures. Existing algorithms are sensitive to differences in pulse pressure and artery stiffness. Some are closely guarded trade secrets. Accurate extraction of systolic and diastolic pressures from the envelope of cuff pressure oscillations remains an open problem in biomedical engineering. Methods A new analysis of relevant anatomy, physiology and physics reveals the mechanisms underlying the production of cuff pressure oscillations as well as a way to extract systolic and diastolic pressures from the envelope of oscillations in any individual subject. Stiffness characteristics of the compressed artery segment can be extracted from the envelope shape to create an individualized mathematical model. The model is tested with a matrix of possible systolic and diastolic pressure values, and the minimum least squares difference between observed and predicted envelope functions indicates the best fit choices of systolic and diastolic pressure within the test matrix. Results The model reproduces realistic cuff pressure oscillations. The regression procedure extracts systolic and diastolic pressures accurately in the face of varying pulse pressure and arterial stiffness. The root mean squared error in extracted systolic and diastolic pressures over a range of challenging test scenarios is 0.3 mmHg. Conclusions A new algorithm based on physics and physiology allows accurate extraction of systolic and diastolic pressures from cuff pressure oscillations in a way that can be validated, criticized, and updated in the public domain.

  2. Multivariate Modeling of Body Mass Index, Pulse Pressure, Systolic and Diastolic Blood Pressure in Chinese Twins

    DEFF Research Database (Denmark)

    Wu, Yili; Zhang, Dongfeng; Pang, Zengchang;

    2015-01-01

    Systolic and diastolic blood pressure, pulse pressure (PP), and body mass index (BMI) are heritable traits in human metabolic health but their common genetic and environmental backgrounds are not well investigated. The aim of this article was to explore the phenotypic and genetic associations among...... PP, systolic blood pressure (SBP), diastolic blood pressure (DBP), and BMI. The studied sample contained 615 twin pairs (17-84 years) collected in the Qingdao municipality. Univariate and multivariate structural equation models were fitted for assessing the genetic and environmental contributions...... model estimated (1) high genetic correlations for DBP with SBP (0.87), PP with SBP (0.75); (2) low-moderate genetic correlations between PP and DBP (0.32), each BP component and BMI (0.24-0.37); (3) moderate unique environmental correlation for PP with SBP (0.68) and SBP with DBP (0.63); (4...

  3. Detrended Fluctuation Analysis of Systolic Blood Pressure Control Loop

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    Galhardo, C E C; de Menezes, M Argollo; Soares, P P S

    2009-01-01

    We use detrended fluctuation analysis (DFA) to study the dynamics of blood pressure oscillations and its feedback control in rats by analyzing systolic pressure time series before and after a surgical procedure that interrupts its control loop. We found, for each situation, a crossover between two scaling regions characterized by exponents that reflect the nature of the feedback control and its range of operation. In addition, we found evidences of adaptation in the dynamics of blood pressure regulation a few days after surgical disruption of its main feedback circuit. Based on the paradigm of antagonistic, bipartite (vagal and sympathetic) action of the central nerve system, we propose a simple model for pressure homeostasis as the balance between two nonlinear opposing forces, successfully reproducing the crossover observed in the DFA of actual pressure signals.

  4. Systolic Blood Pressure Intervention Trial (SPRINT) and Target Systolic Blood Pressure in Future Hypertension Guidelines.

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    Egan, Brent M; Li, Jiexiang; Wagner, C Shaun

    2016-08-01

    The Systolic Blood Pressure (SBP, mm Hg) Intervention Trial (SPRINT) showed that targeting SBP SPRINT has 2 implicit assumptions that could impact future US hypertension guidelines: (1) standard therapy controlled SBP similarly to that in adults with treated hypertension and (2) intensive therapy produced a lower mean SBP than in adults with treated hypertension and SBP SPRINT-like participants aged ≥50 years; group 2 consisted of participants all aged ≥18 years; and group 3 consisted of participants aged ≥18 years excluding group 1 but otherwise similar to SPRINT-like participants except high cardiovascular risk. Mean SBPs in groups 1, 2, and 3 were 133.0, 130.1, and 124.6, with 66.2%, 72.2%, and 81.9%, respectively, controlled to SBP SPRINT-like group had higher mean SBP than comparison groups, yet lower than SPRINT standard treatment group and (2) among groups 1 to 3 with SBP SPRINT intensive treatment. SPRINT results suggest that treatment should be continued and not reduced when treated SBP is SPRINT-like subset. Furthermore, increasing the percentage of treated adults with SBP SPRINT intensive treatment SBP without lowering treatment goals.

  5. Automatic noninvasive measurement of systolic blood pressure using photoplethysmography

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    Glik Zehava

    2009-10-01

    Full Text Available Abstract Background Automatic measurement of arterial blood pressure is important, but the available commercial automatic blood pressure meters, mostly based on oscillometry, are of low accuracy. Methods In this study, we present a cuff-based technique for automatic measurement of systolic blood pressure, based on photoplethysmographic signals measured simultaneously in fingers of both hands. After inflating the pressure cuff to a level above systolic blood pressure in a relatively slow rate, it is slowly deflated. The cuff pressure for which the photoplethysmographic signal reappeared during the deflation of the pressure-cuff was taken as the systolic blood pressure. The algorithm for the detection of the photoplethysmographic signal involves: (1 determination of the time-segments in which the photoplethysmographic signal distal to the cuff is expected to appear, utilizing the photoplethysmographic signal in the free hand, and (2 discrimination between random fluctuations and photoplethysmographic pattern. The detected pulses in the time-segments were identified as photoplethysmographic pulses if they met two criteria, based on the pulse waveform and on the correlation between the signal in each segment and the signal in the two neighboring segments. Results Comparison of the photoplethysmographic-based automatic technique to sphygmomanometry, the reference standard, shows that the standard deviation of their differences was 3.7 mmHg. For subjects with systolic blood pressure above 130 mmHg the standard deviation was even lower, 2.9 mmHg. These values are much lower than the 8 mmHg value imposed by AAMI standard for automatic blood pressure meters. Conclusion The photoplethysmographic-based technique for automatic measurement of systolic blood pressure, and the algorithm which was presented in this study, seems to be accurate.

  6. Women, Hypertension, and the Systolic Blood Pressure Intervention Trial.

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    Wenger, Nanette K; Ferdinand, Keith C; Bairey Merz, C Noel; Walsh, Mary Norine; Gulati, Martha; Pepine, Carl J

    2016-10-01

    Hypertension accounts for approximately 1 in 5 deaths in American women and is the major contributor to many comorbid conditions. Although blood pressure lowering reduces cardiovascular disease outcomes, considerable uncertainty remains on best management in women. Specifically, female blood pressure treatment goals have not been established, particularly among older and African American and Hispanic women, for whom hypertension prevalence, related adverse outcomes, and poor control rates are high. The Systolic Blood Pressure Intervention Trial (SPRINT) planned to clarify optimal blood pressure management in both sexes. Although confirming that a lower blood pressure goal is generally better, because female enrollment and event rates were low and follow-up shortened, outcomes differences in women were not statistically significant. Thus optimal blood pressure goals for women have not been established with the highest evidence. This review addresses SPRINT's significance and key remaining knowledge gaps in optimal blood pressure management to improve women's health.

  7. Decreasing systolic blood pressure with isometric muscle training: a CAT

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    Alexis Espinoza Salinas

    2014-09-01

    Full Text Available INTRODUCTION Hypertension is a major risk factor for cardiovascular diseases such as coronary heart disease or heart failure. One of the interventions for the management of this disorder is isometric muscle training on upper and lower limbs. PURPOSE To prove the validity and applicability of results regarding the effectiveness of isometric training in hypertensive subjects. We also attempt to answer the following question: what is the effectiveness of isometric muscle training on the decrease of systolic blood pressure in hypertensive patients? METHODS Critical appraisal of the systematic review and meta-analysis “Isometric exercise training for blood pressure management”. RESULTS Isometric training reduces systolic blood pressure in normotensive and medicated hypertensive subjects, with a standardized mean difference of 6.77 mm Hg (95% confidence interval: 7.93-5.62. CONCLUSION It is reasonable to recommend isometric muscle training with the aim of lowering systolic blood pressure, considering the impact of the results of the articles analyzed and the applicability of this type of training.

  8. Birth weight and systolic blood pressure in adolescence and adulthood

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    Gamborg, Michael; Byberg, Liisa; Rasmussen, Finn

    2007-01-01

    The authors investigated the shape, sex- and age-dependency, and possible confounding of the association between birth weight and systolic blood pressure (SBP) in 197,954 adults from 20 Nordic cohorts (birth years 1910-1987), one of which included 166,249 Swedish male conscripts. Random-effects m......The authors investigated the shape, sex- and age-dependency, and possible confounding of the association between birth weight and systolic blood pressure (SBP) in 197,954 adults from 20 Nordic cohorts (birth years 1910-1987), one of which included 166,249 Swedish male conscripts. Random...... with a birth weight greater than 4 kg, SBP increased with birth weight (p groups (p

  9. Euglycemic clamp insulin sensitivity and longitudinal systolic blood pressure

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    Petrie, John R; Malik, Muhammad Omar; Balkau, Beverley

    2013-01-01

    Insulin resistance may be an independent risk factor for the development of hypertension, but change in blood pressure (BP) over time has not been adequately studied in healthy individuals fully characterized for insulin sensitivity. In the Relationship between Insulin Sensitivity...... and Cardiovascular disease (RISC) study, we measured insulin sensitivity (M/I) using the euglycemic clamp technique in 1073 healthy European adults (587 women, 486 men) aged 30 to 60 years followed up 3 years later. Systolic BP (SBP) at baseline was higher in insulin-resistant women (ie, those in the low sex...

  10. Efficacy of combination therapy for systolic blood pressure in patients with severe systolic hypertension: the Systolic Evaluation of Lotrel Efficacy and Comparative Therapies (SELECT) study.

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    Neutel, Joel M; Smith, David H G; Weber, Michael A; Schofield, Lesley; Purkayastha, Das; Gatlin, Marjorie

    2005-11-01

    Systolic hypertension is predominant among patients over 50 years of age, is a more important cardiovascular risk factor than diastolic blood pressure, and is more difficult to control than diastolic blood pressure. Consequently, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) recommends combination therapy as first-line treatment for patients with stage 2 hypertension. In the Systolic Evaluation of Lotrel Efficacy and Comparative Therapies (SELECT) study, 24-hour ambulatory blood pressure monitoring was used to identify patients with systolic hypertension and to determine the impact of 8 weeks of treatment with either amlodipine besylate/benazepril HCl 5/20 mg combination therapy (n=149), amlodipine besylate 5 mg (n=146), or benazepril HCl 20 mg (n=148). Combination therapy was significantly more effective in reducing systolic blood pressure and pulse pressure than either monotherapy (pamlodipine-treated group. The combination of amlodipine besylate/benazepril HCl given to patients with stage 2 systolic hypertension resulted in significantly greater reductions in blood pressure and pulse pressure than those seen with monotherapy and was at least as well tolerated as the separate components. This data supports the recommendation of the JNC 7 for the use of combination therapy in patients with stage 2 hypertension.

  11. Systolic blood pressure and (cardiac) mortality over 15 years after venous coronary bypass surgery.

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    Voors, A A; van Brussel, B L; Kelder, J C; Plokker, H W

    1997-10-01

    The aim of the present study was to determine the influence of pre-operative systolic blood pressure and systolic blood pressure 1 and 5 years after venous coronary bypass surgery on subsequent cardiac and non-cardiac mortality. A prospective 15 years follow-up study. A series of 446 consecutive coronary bypass surgery patients, operated on between April 1976 and April 1977. According to their systolic blood pressure, patients were divided into five groups. Systolic blood pressure 5 years after surgery, but not pre-operative systolic blood pressure, was an independent predictor of cardiac mortality. Multivariate Cox proportional hazards analysis revealed that pre-operative systolic blood pressure was not associated with cardiac mortality, while higher systolic blood pressure 1 year after surgery showed a trend towards increased cardiac mortality. Systolic blood pressure 5 years after surgery appeared to be a strong independent predictor of cardiac mortality during the subsequent follow-up period. Patients with a systolic blood pressure of 130-139 mmHg had the lowest risk. Compared to this group, the cardiac mortality risk in patients with a systolic blood pressure 5 years after surgery of 140-149 mmHg, 150-159 mmHg and > or = 160 mmHg, was 2.3 (1.2 to 4.6), 3.4 (1.6 to 7.1) and 3.1 (1.4 to 6.5) times higher. Systolic blood pressure < 130 mmHg 5 years after surgery was also associated with a 2.3 times (1.1 to 4.7) times increased risk for cardiac mortality, compared to patients with a systolic blood pressure of 130-139 mmHg. These findings underline the importance of systolic blood pressure control in the initial years after coronary bypass surgery.

  12. The TRINITY Study: distribution of systolic blood pressure reductions

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    Sugimoto DH

    2013-07-01

    Full Text Available Danny H Sugimoto,1 Steven G Chrysant,2 Michael Melino,3 James Lee,3 Victor Fernandez,3 Reinilde Heyrman41Cedar-Crosse Research Center and Rush Medical College, Chicago, IL, USA; 2Oklahoma Cardiovascular and Hypertension Center and Department of Cardiology, University of Oklahoma College of Medicine, Oklahoma City, OK, USA; 3Department of Clinical Development, Daiichi Sankyo, Inc, Parsippany, NJ, USA; 4Formerly of the Department of Clinical Development, Daiichi Sankyo, Inc, Parsippany, NJ, USABackground: Elevated systolic blood pressure is more difficult to control than elevated diastolic blood pressure. The objective of this prespecified analysis of the Triple Therapy with Olmesartan Medoxomil, Amlodipine, and Hydrochlorothiazide in Hypertensive Patients Study (TRINITY was to compare the efficacy of olmesartan medoxomil (OM 40 mg, amlodipine besylate (AML 10 mg, and hydrochlorothiazide (HCTZ 25 mg triple-combination treatment with the component dual-combination treatments in reducing elevated seated systolic blood pressure (SeSBP.Methods: The 12-week TRINITY study randomized participants to either one of the three component dual-combination treatments (OM 40 mg/AML 10 mg, OM 40 mg/HCTZ 25 mg, or AML 10 mg/HCTZ 25 mg or the triple-combination treatment. The primary outcome of this analysis was the categorical distribution of SeSBP reductions at week 12 from baseline with OM 40 mg/AML 10 mg/HCTZ 25 mg versus the dual-combination treatments.Results: SeSBP reductions >50 mmHg were seen in 24.4% of participants receiving triple-combination treatment versus 8.1%–15.8% receiving dual-combination treatment. More participants receiving triple-combination treatment achieved the SeSBP target of <140 mmHg (73.6% versus 51.3%–58.8%; P < 0.001 and the seated blood pressure target of <140/90 mmHg (69.9% versus 41.1%–53.4%; P < 0.001. Prevalence and severity of adverse events were similar in all treatment groups.Conclusion: Treatment with OM 40 mg/AML 10

  13. [Twenty-four hour time and frequency domain variability of systolic blood pressure and heart rate in an experimental model of arterial hypertension plus obesity].

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    Pelat, M; Verwaerde, P; Lazartiques, E; Cabrol, P; Galitzky, J; Berlan, M; Montastruc, J L; Senard, J M

    1998-08-01

    Modifications of heart rate (HR) and systolic blood pressure (SBP) variabilities (V) have been reported in the human syndrome arterial hypertension plus insulin-resistance. The aim of this study was to characterize the 24 h SBPV and HRV in both time and frequency domains during weight increase in dogs fed ad libitum with a high fat diet. Implantable transmitter units for measurement of blood pressure and heart rate were surgically implanted in five beagle male dogs. BP and HR were continuously recorded using telemetric measurements during 24 hours, before and after 6 and 9 weeks of hypercaloric diet in quiet animals submitted to a 12h light-dark cycle. To study nychtemeral cycle of SBP and HR, two periods were chosen: day (from 6.00 h to 19.00 h) and night (from 23.00 h to 6.00 h). Spontaneous baroreflex efficiency was measured using the sequence method. Spectral variability of HR and SBP was analyzed using a fast Fourier transformation on 512 consecutive values and normalized units of low (LF: 50-150 mHz, reflecting sympathetic activity) and high (HF: respiratory rate +/- 50 mHz, reflecting parasympathetic activity) frequency bands were calculated. The energy of total spectrum (from 0.004 to 1 Hz) was also studied. Body weight (12.4 +/- 0.9 vs 14.9 +/- 0.9 kg, p < 0.05). SBP (132 +/- 1 vs 147 +/- 1 mmHg, p < 0.05) significantly increased after 9 weeks of hypercaloric diet. A nycthemeral HR rhythm was present at baseline (day: 79 +/- 1 vs night: 71 +/- 1 bpm) but not after 9 weeks (day: 91 +/- 4 bpm ; night: 86 +/- 2 bpm). Concomitantly, the efficiency of spontaneous baroreflex decreased at 6 weeks (36 +/- 1 vs 42 +/- 2 mmHg/ms, p < 0.05). A significant decrease in HF energy of HRV was found after 6 but not after 9 weeks. LF energy of SBPV was increased at 6 but not at 9 weeks (table). [table: see text] In conclusion, this study shows that an hyperlipidic and hypercaloric diet induces transient variations in autonomic nervous system activity which could be the

  14. Target blood pressure for treatment of isolated systolic hypertension in the elderly: valsartan in elderly isolated systolic hypertension study.

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    Ogihara, Toshio; Saruta, Takao; Rakugi, Hiromi; Matsuoka, Hiroaki; Shimamoto, Kazuaki; Shimada, Kazuyuki; Imai, Yutaka; Kikuchi, Kenjiro; Ito, Sadayoshi; Eto, Tanenao; Kimura, Genjiro; Imaizumi, Tsutomu; Takishita, Shuichi; Ueshima, Hirotsugu

    2010-08-01

    In this prospective, randomized, open-label, blinded end point study, we aimed to establish whether strict blood pressure control (blood pressure control (> or =140 mm Hg to hypertension. We divided 3260 patients aged 70 to 84 years with isolated systolic hypertension (sitting blood pressure 160 to 199 mm Hg) into 2 groups, according to strict or moderate blood pressure treatment. A composite of cardiovascular events was evaluated for > or =2 years. The strict control (1545 patients) and moderate control (1534 patients) groups were well matched (mean age: 76.1 years; mean blood pressure: 169.5/81.5 mm Hg). Median follow-up was 3.07 years. At 3 years, blood pressure reached 136.6/74.8 mm Hg and 142.0/76.5 mm Hg, respectively. The blood pressure difference between the 2 groups was 5.4/1.7 mm Hg. The overall rate of the primary composite end point was 10.6 per 1000 patient-years in the strict control group and 12.0 per 1000 patient-years in the moderate control group (hazard ratio: 0.89; [95% CI: 0.60 to 1.34]; P=0.38). In summary, blood pressure targets of or = 70 years of age with isolated systolic hypertension, although our trial was underpowered to definitively determine whether strict control was superior to less stringent blood pressure targets.

  15. Clinical usefulness of the second peak of radial systolic blood pressure for estimation of aortic systolic blood pressure.

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    Kohara, K; Tabara, Y; Tomita, H; Nagai, T; Igase, M; Miki, T

    2009-08-01

    Central aortic blood pressure (BP), obtained from radial arterial waveform using the transfer function method (TFM), has been shown to have prognostic value independently of brachial BP. In this study, the relationship between peripheral systolic BP (SBP) and aortic SBP was evaluated. We further investigated whether TFM-derived aortic SBP can be estimated by information obtained from the radial waveform. The radial waveform was analysed to obtain the first peak of radial SBP (SBP1), second peak of radial SBP (SBP2), radial augmentation index (AI) (radial (SBP2-DBP)/(SBP1-DBP) x 100 and aortic SBP and AI using TFM in 233 subjects in the supine position. Measurements were repeated after changing position to the prone position. The constructed equation was validated in 149 community residents with different backgrounds. Radial SBP2 was closer to TFM-derived aortic SBP compared with brachial SBP. TFM-derived aortic SBP was approximated by the equation: aortic SBP=18.9-radial SBP2-0.03 x HR-0.214 x radial AI (r2=0.992). The equation was also applicable to predicting aortic SBP in the prone position as well as in different populations (mean difference between predicted aortic SBP and TFM-derived aortic SBP: -0.01+/-1.34 and 1.05+/-1.47 mm Hg, respectively). Radial arterial waveform analysis can be used for estimation of TFM-derived aortic SBP.

  16. [Development of an automatic pneumatic tourniquet system that determines pressures in synchrony with systolic blood pressure].

    Science.gov (United States)

    Liu, Hongyun; Li, Kaiyuan; Zhang, Zhengbo; Guo, Junyan; Wang, Weidong

    2012-11-01

    The correlation coefficients between arterial occlusion pressure and systolic blood pressure, diastolic blood pressure, limb circumference, body mass etc were obtained through healthy volunteer experiments, in which tourniquet were applied on upper/lower extremities. The prediction equations were derived from the data of experiments by multiple regression analysis. Based on the microprocessor C8051F340, a new pneumatic tourniquet system that can determine tourniquet pressure in synchrony with systolic blood pressure was developed and verified the function and stability of designed system. Results showed that the pneumatic tourniquet which automatically adjusts occlusion pressure in accordance with systolic blood pressure could stop the flow of blood to get a bloodless field.

  17. Systolic blood pressure and short-term mortality in the emergency department and prehospital setting

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    Kristensen, Anders Kasper Bruun; Holler, Jon Gitz; Mikkelsen, Søren;

    2015-01-01

    staffed mobile emergency care unit in Odense between 2007 and 2013. We used the first recorded systolic blood pressure and the main outcome was 7-day mortality. Best performing thresholds were identified with methods based on receiver operating characteristics (ROC) and multivariate regression......INTRODUCTION: Systolic blood pressure is a widely used tool to assess circulatory function in acutely ill patients. The systolic blood pressure limit where a given patient should be considered hypotensive is the subject of debate and recent studies have advocated higher systolic blood pressure...... thresholds than the traditional 90 mmHg. The aim of this study was to identify the best performing systolic blood pressure thresholds with regards to predicting 7-day mortality and to evaluate the applicability of these in the emergency department as well as in the prehospital setting. METHODS...

  18. Valuation of Normal Range of Ankle Systolic Blood Pressure in Subjects with Normal Arm Systolic Blood Pressure.

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    Yi Gong

    Full Text Available This study aimed to establish a normal range for ankle systolic blood pressure (SBP.A total of 948 subjects who had normal brachial SBP (90-139 mmHg at investigation were enrolled. Supine BP of four limbs was simultaneously measured using four automatic BP measurement devices. The ankle-arm difference (An-a on SBP of both sides was calculated. Two methods were used for establishing normal range of ankle SBP: the 99% method was decided on the 99% reference range of actual ankle BP, and the An-a method was the sum of An-a and the low or up limits of normal arm SBP (90-139 mmHg.Whether in the right or left side, the ankle SBP was significantly higher than the arm SBP (right: 137.1 ± 16.9 vs 119.7 ± 11.4 mmHg, P<0.05. Based on the 99% method, the normal range of ankle SBP was 94~181 mmHg for the total population, 84~166 mmHg for the young (18-44 y, 107~176 mmHg for the middle-aged(45-59 y and 113~179 mmHg for the elderly (≥ 60 y group. As the An-a on SBP was 13 mmHg in the young group and 20 mmHg in both middle-aged and elderly groups, the normal range of ankle SBP on the An-a method was 103-153 mmHg for young and 110-160 mmHg for middle-elderly subjects.A primary reference for normal ankle SBP was suggested as 100-165 mmHg in the young and 110-170 mmHg in the middle-elderly subjects.

  19. Comparison of 2 models for gene-environment interactions: an example of simulated gene-medication interactions on systolic blood pressure in family-based data.

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    Fernández-Rhodes, Lindsay; Hodonsky, Chani J; Graff, Mariaelisa; Love, Shelly-Ann M; Howard, Annie Green; Seyerle, Amanda A; Avery, Christy L; Chittoor, Geetha; Franceschini, Nora; Voruganti, V Saroja; Young, Kristin; O'Connell, Jeffrey R; North, Kari E; Justice, Anne E

    2016-01-01

    Nearly half of adults in the United States who are diagnosed with hypertension use blood-pressure-lowering medications. Yet there is a large interindividual variability in the response to these medications. Two complementary gene-environment interaction methods have been published and incorporated into publicly available software packages to examine interaction effects, including whether genetic variants modify the association between medication use and blood pressure. The first approach uses a gene-environment interaction term to measure the change in outcome when both the genetic marker and medication are present (the "interaction model"). The second approach tests for effect-size differences between strata of an environmental exposure (the "med-diff" approach). However, no studies have quantitatively compared how these methods perform with respect to 1 or 2 degree of freedom (DF) tests or in family-based data sets. We evaluated these 2 approaches using simulated genotype-medication response interactions at 3 single nucleotide polymorphisms (SNPs) across a range of minor allele frequencies (MAFs 0.1-5.4 %) using the Genetic Analysis Workshop 19 family sample. The estimated interaction effect sizes were on average larger in the interaction model approach compared to the med-diff approach. The true positive proportion was higher for the med-diff approach for SNPs less than 1 % MAF, but higher for the interaction model when common variants were evaluated (MAF >5 %). The interaction model produced lower false-positive proportions than expected (5 %) across a range of MAFs for both the 1DF and 2DF tests. In contrast, the med-diff approach produced higher but stable false-positive proportions around 5 % across MAFs for both tests. Although the 1DF tests both performed similarly for common variants, the interaction model estimated true interaction effects with less bias and higher true positive proportions than the med-diff approach. However, if rare variation (MAF

  20. Inter arm systolic blood pressure difference is associated with a high prevalence of cardio vascular diseases

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    Narsingh Verma

    2016-04-01

    Results: The systolic blood pressure on right arm was 118.8+/-11.5 mmHg and 11.7+/-7.72 mmHg left arm. Result significantly showed higher mean systolic blood pressure on right arm. There were 54, 17 and 29 participants with inter-arm systolic blood pressure difference of 30. Out of 100 subjects, 11 subject having inter-arm systolic blood pressure difference and #8805;10 mmHg was associated with a family history of diabetes or hypertension. Conclusions: Presence of inter-arm blood pressure difference with having family history of hypertension or diabetes is more susceptible to develop cardiovascular disorder in future. [Int J Res Med Sci 2016; 4(4.000: 1177-1180

  1. Familial and genomic analyses of postural changes in systolic and diastolic blood pressure.

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    Harrap, Stephen B; Cui, Jisheng S; Wong, Zilla Y H; Hopper, John L

    2004-03-01

    The physiological adaptation to the erect posture involves integrated neural and cardiovascular responses that might be determined by genetic factors. We examined the familial- and individual-specific components of variance for postural changes in systolic and diastolic blood pressure in 767 volunteer nuclear adult families from the Victorian Family Heart Study. In 274 adult sibling pairs, we made a genome-wide scan using 400 markers for quantitative trait loci linked with the postural changes in systolic and diastolic pressures. Overall, systolic pressure did not change on standing, but there was considerable variation in this phenotype (SD=8.1 mm Hg). Familial analyses revealed that 25% of the variance of change in systolic pressure was attributable to genetic factors. In contrast, diastolic pressure increased by 6.3 mm Hg (SD=7.0 mm Hg) on standing and there was no evidence of contributory genetic factors. Multipoint quantitative genome linkage mapping suggested evidence (Z=3.2) of linkage of the postural change in systolic pressure to chromosome 12 but found no genome-wide evidence of linkage for the change in diastolic pressure. These findings suggest that genetic factors determine whether systolic pressure decreases or increases when one stands, possibly as the result of unidentified alleles on chromosome 12. The genetics of postural changes in systolic blood pressure might reflect the general buffering function of the baroreflex; thereby, the predisposition to sudden decreases or increases in systolic pressure might cause postural hypotension or vessel wall disruption, respectively.

  2. Invasively Measured Aortic Systolic Blood Pressure and Office Systolic Blood Pressure in Cardiovascular Risk Assessment: A Prospective Cohort Study

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    Laugesen, Esben; Knudsen, Søren T; Hansen, Klavs W

    2016-01-01

    myocardial infarction, stroke, and death. Discrimination and reclassification were assessed using Harrell's C and the Continuous Net Reclassification Index. Data were analyzed with and without stratification by diabetes mellitus status. During a median follow-up period of 3.7 years (range: 0.1-10.8 years......), 422 strokes, 511 myocardial infarctions, and 1530 deaths occurred. Both office and aortic systolic BP were associated with stroke in patients with diabetes mellitus (hazard ratio per 10 mm Hg, 1.18 [95% confidence interval, 1.07-1.30] and 1.14 [95% confidence interval, 1.05-1.24], respectively...

  3. Effects of Atorvastatin on Warfarin-induced Aortic Medial Calcification and Systolic Blood Pressure in Rats

    Institute of Scientific and Technical Information of China (English)

    Chengyun LIU; Jingjing WAN; Qunfang YANG; Benling QI; Wen PENG; Xuelin CHEN

    2008-01-01

    Summary: The effect of atorvastatin on warfarin-induced aortic medial calcification and systolic blood pressure (SBP) of rats induced by warfarin was studied. Thirty healthy and adult rats were randomly divided into Warfarin group (n=10), Atorvastatin group (n=10) and normal control group (n=10). Caudal arterial pressure of rats was measured once a week, and 4 weeks later, aorta was obtained. Elastic fiber, collagen fiber and calcium accumulation in tunica media of cells were measured by Von Kossa staining. The results showed that warfarin treatment led to elevation of systolic blood pressure and aortic medial calcification. The chronic treatment also increased collagen, but decreased elastin in the aorta. However, the atorvastatin treatment had adverse effects. It was concluded that treatment with atorvastatin presented evidence of blood pressure lowing and calcification reducing. These data demonstrate that atorvastatin protected aortic media from warfarin-induced calcification and elevation of systolic blood pressure.

  4. Effects of parental smoking on exercise systolic blood pressure in adolescents.

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    Hacke, Claudia; Weisser, Burkhard

    2015-05-11

    In adults, exercise blood pressure seems to be more closely related to cardiovascular risk than resting blood pressure; however, few data are available on the effects of familial risk factors, including smoking habits, on exercise blood pressure in adolescents. Blood pressure at rest and during exercise, parental smoking, and other familial risk factors were investigated in 532 adolescents aged 12 to 17 years (14.6±1.5 years) in the Kiel EX.PRESS. (EXercise PRESSure) Study. Exercise blood pressure was determined at 1.5 W/kg body weight using a standardized submaximal cycle ergometer test. Mean resting blood pressure was 113.1±12.8/57.2±7.1 mm Hg, and exercise blood pressure was 149.9±19.8/54.2±8.6 mm Hg. Parental smoking increased exercise systolic blood pressure (+4.0 mm Hg, 3.1 to 4.9; P=0.03) but not resting blood pressure of the subjects (adjusted for age, sex, height, body mass index percentile, fitness). Parental overweight and familial hypertension were related to both higher resting and exercise systolic blood pressure values, whereas associations with an inactive lifestyle and a low educational level of the parents were found only with adolescents' blood pressure during exercise. The cumulative effect of familial risk factors on exercise systolic blood pressure was more pronounced than on blood pressure at rest. Parental smoking might be a novel risk factor for higher blood pressure, especially during exercise. In addition, systolic blood pressure during a submaximal exercise test was more closely associated with familial risk factors than was resting blood pressure, even in adolescents. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  5. Systematic review and meta-analysis of preterm birth and later systolic blood pressure.

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    de Jong, Femke; Monuteaux, Michael C; van Elburg, Ruurd M; Gillman, Matthew W; Belfort, Mandy B

    2012-02-01

    Lower birth weight because of fetal growth restriction is associated with higher blood pressure later in life, but the extent to which preterm birth (blood pressure is less clear. We performed a systematic review of 27 observational studies that compared the resting or ambulatory systolic blood pressure or diagnosis of hypertension among children, adolescents, and adults born preterm or very low birth weight with those born at term. We performed a meta-analysis with the subset of 10 studies that reported the resting systolic blood pressure difference in millimeters of mercury with 95% CIs or SEs. We assessed methodologic quality with a modified Newcastle-Ottawa Scale. The 10 studies were composed of 1342 preterm or very low birth weight and 1738 term participants from 8 countries. The mean gestational age at birth of the preterm participants was 30.2 weeks (range: 28.8-34.1 weeks), birth weight was 1280 g (range: 1098-1958 g), and age at systolic blood pressure measurement was 17.8 years (range: 6.3-22.4 years). Former preterm or very low birth weight infants had higher systolic blood pressure than term infants (pooled estimate: 2.5 mm Hg [95% CI: 1.7-3.3 mm Hg]). For the 5 highest quality studies, the systolic blood pressure difference was slightly greater, at 3.8 mm Hg (95% CI: 2.6-5.0 mm Hg). We conclude that infants who are born preterm or very low birth weight have modestly higher systolic blood pressure later in life and may be at increased risk for developing hypertension and its sequelae.

  6. On-Treatment Blood Pressure and Cardiovascular Outcomes in Older Adults With Isolated Systolic Hypertension.

    Science.gov (United States)

    Yano, Yuichiro; Rakugi, Hiromi; Bakris, George L; Lloyd-Jones, Donald M; Oparil, Suzanne; Saruta, Takao; Shimada, Kazuyuki; Matsuoka, Hiroaki; Imai, Yutaka; Ogihara, Toshio

    2017-02-01

    Our aim was to assess optimal on-treatment blood pressure (BP) at which cardiovascular disease (CVD) and all-cause mortality risks are minimized in Japanese older adults with isolated systolic hypertension. We used data from the VALISH study (Valsartan in Elderly Isolated Systolic Hypertension) that recruited older adults (n=3035; mean age, 76 years) with systolic BP (SBP) of ≥160 mm Hg and diastolic BP of adults with isolated systolic hypertension, SBP in the range between 130 and 144 mm Hg was associated with minimal adverse outcomes and a reduction in CVD and all-cause mortality. The BP range will need to be confirmed in randomized controlled trials. URL: https://www.clinicaltrials.gov. Unique identifier: NCT00151229. © 2017 American Heart Association, Inc.

  7. Decreasing systolic blood pressure and declining mortality rates in an untreated population

    DEFF Research Database (Denmark)

    Andersen, Ulla O; Marott, Jacob L; Jensen, Gorm B

    2011-01-01

    The aim of the present study was to evaluate developments in 30 years mortality risk that may be associated with developments in population systolic blood pressure (SBP) and to evaluate possible secular trends in BP-associated mortality risk in the untreated population.......The aim of the present study was to evaluate developments in 30 years mortality risk that may be associated with developments in population systolic blood pressure (SBP) and to evaluate possible secular trends in BP-associated mortality risk in the untreated population....

  8. Impact of systolic blood pressure on visit-to-visit blood pressure variability in middle-aged and elderly people

    Institute of Scientific and Technical Information of China (English)

    陈朔华

    2013-01-01

    Objective To observe the impact of systolic blood pressure(SBP)on visit-to-visit blood pressure variability(BPV) in middle-aged and elderly people.Methods Visit-to-visit BPV was determined in 5440 workers in the

  9. Impact of Age on the Importance of Systolic and Diastolic Blood Pressures for Stroke Risk

    DEFF Research Database (Denmark)

    Vishram, Julie K K; Borglykke, Anders; Andreasen, Anne H;

    2012-01-01

    This study investigates age-related shifts in the relative importance of systolic (SBP) and diastolic (DBP) blood pressures as predictors of stroke and whether these relations are influenced by other cardiovascular risk factors. Using 34 European cohorts from the MOnica, Risk, Genetics, Archiving...

  10. Systolic blood pressure reactivity during submaximal exercise and acute psychological stress in youth

    Science.gov (United States)

    Background: Studies in youth show an association between systolic blood-pressure (SBP) reactivity to acute psychological stress and carotid artery intima-media thickness (CIMT). However, it has not yet been determined whether SBP reactivity during submaximal exercise is also associated with CIMT i...

  11. Interarm differences in systolic blood pressure and mortality among US army veterans

    DEFF Research Database (Denmark)

    White, James; Mortensen, Laust Hvas; Kivimäki, Mika

    2014-01-01

    BACKGROUND: Differences between the arms in systolic blood pressure (SBP) of ≥10 mmHg have been associated with an increased risk of mortality in patients with hypertensive and chronic renal disease. For the first time, we examined these relationships in a non-clinical population. DESIGN: Cohort ...

  12. Dairy consumption, systolic blood pressure, and risk of hypertension: Mendelian randomization study

    Science.gov (United States)

    This study examined whether previous observed inverse associations of dairy intake with systolic blood pressure and risk of hypertension were causal. A Mendelian randomization study was employed, using the single nucleotide polymorphism rs4988235 related to lactase persistence as an instrumental var...

  13. The measurement of digital systolic blood pressure by strain gauge technique

    DEFF Research Database (Denmark)

    Nielsen, P E; Bell, G; Lassen, N A

    1972-01-01

    The systolic blood pressure on the finger, toe, and ankle has been measured by a strain gauge technique in 10 normal subjects aged 17-31 years and 14 normal subjects aged 43-57 years. The standard deviation in repeated measurements lies between 2 and 6 mm Hg. The finger pressure in the younger...

  14. Total flying hours and risk of high systolic blood pressure in the civilian pilot in Indonesia

    Directory of Open Access Journals (Sweden)

    Ferdi Afian

    2016-07-01

    Full Text Available Abstrak Latar belakang: Tekanan darah sistolik tinggi di antara pilot sipil antara lain akan menyebabkan gangguan kardiovaskular sehingga akan mengganggu kelancaran penerbangan. Tujuan penelitian ini ialah untuk mengetahui faktor-faktor dominan terhadap tekanan darah sistolik tinggi pada pilot sipil. Metode: Penelitian potong lintang dengan metode sampling purposif pada pilot yang melakukan pemeriksaan kesehatan berkala di Balai Kesehatan Penerbangan pada tanggal 18-29 Mei 2015. Data yang dikumpulkan adalah karakteristik demografi dan pekerjaan, klinis, kebiasaan olahraga, kebiasaan makan, indeks massa tubuh dan riwayat penyakit. Tekanan darah sistolik tinggi ialah tekanan darah sistolik140 mmHg atau lebih. Hasil: Dari 690 pilot yang melakukan pemeriksaan kesehatan berkala, 428 pilot laki-laki bersedia berpartisipasi mengikuti penelitian ini. Usia dan riwayat penyakit hipertensi merupakan faktor risiko dominan yang berhubungan dengan tekanan darah sistolik tinggi. Jika dibandingkan dengan pilot usia 19-39 tahun, yang berusia 40-65 tahun mempunyai 15,1 kali lipat lebih besar risiko terkena tekanan darah sistolik tinggi [rasio odds suaian (ORa= 15,12; p= 0,001]. Pilot dengan riwayat penyakit hipertensi dibandingkan dengan yang tidak ada riwayat memiliki risiko tekanan darah sistolik tinggi 93,2 kali lipat lebih besar (ORa= 93,21; p= 0,001 Kesimpulan: Usia 40-65 tahun dan memiliki riwayat hipertensi meningkatkan risiko tekanan darah sistolik tinggi di antara pilot sipil di Indonesia. Kata kunci: tekanan darah sistolik, total jam terbang, pilot sipil, Indonesia.  Abstract Background: Systolic high blood pressure among civilian pilots among others will cause cardiovascular disease and this condition will disrupt the flight.The purpose of this study was to identified the dominant factors related to high systolic blood pressure in the civilian pilots. Methods: A cross-sectional study with a purposive sampling method on a pilot who performed periodic

  15. Total flying hours and risk of high systolic blood pressure in the civilian pilot in Indonesia

    Directory of Open Access Journals (Sweden)

    Ferdi Afian

    2016-07-01

    Full Text Available Abstrak Latar belakang: Tekanan darah sistolik tinggi di antara pilot sipil antara lain akan menyebabkan gangguan kardiovaskular sehingga akan mengganggu kelancaran penerbangan. Tujuan penelitian ini ialah untuk mengetahui faktor-faktor dominan terhadap tekanan darah sistolik tinggi pada pilot sipil. Metode: Penelitian potong lintang dengan metode sampling purposif pada pilot yang melakukan pemeriksaan kesehatan berkala di Balai Kesehatan Penerbangan pada tanggal 18-29 Mei 2015. Data yang dikumpulkan adalah karakteristik demografi dan pekerjaan, klinis, kebiasaan olahraga, kebiasaan makan, indeks massa tubuh dan riwayat penyakit. Tekanan darah sistolik tinggi ialah tekanan darah sistolik140 mmHg atau lebih. Hasil: Dari 690 pilot yang melakukan pemeriksaan kesehatan berkala, 428 pilot laki-laki bersedia berpartisipasi mengikuti penelitian ini. Usia dan riwayat penyakit hipertensi merupakan faktor risiko dominan yang berhubungan dengan tekanan darah sistolik tinggi. Jika dibandingkan dengan pilot usia 19-39 tahun, yang berusia 40-65 tahun mempunyai 15,1 kali lipat lebih besar risiko terkena tekanan darah sistolik tinggi [rasio odds suaian (ORa= 15,12; p= 0,001]. Pilot dengan riwayat penyakit hipertensi dibandingkan dengan yang tidak ada riwayat memiliki risiko tekanan darah sistolik tinggi 93,2 kali lipat lebih besar (ORa= 93,21; p= 0,001 Kesimpulan: Usia 40-65 tahun dan memiliki riwayat hipertensi meningkatkan risiko tekanan darah sistolik tinggi di antara pilot sipil di Indonesia. Kata kunci: tekanan darah sistolik, total jam terbang, pilot sipil, Indonesia.  Abstract Background: Systolic high blood pressure among civilian pilots among others will cause cardiovascular disease and this condition will disrupt the flight.The purpose of this study was to identified the dominant factors related to high systolic blood pressure in the civilian pilots. Methods: A cross-sectional study with a purposive sampling method on a pilot who performed periodic

  16. Dairy consumption, systolic blood pressure, and risk of hypertension: Mendelian randomization study.

    Science.gov (United States)

    Ding, Ming; Huang, Tao; Bergholdt, Helle Km; Nordestgaard, Børge G; Ellervik, Christina; Qi, Lu

    2017-03-16

    Objective To examine whether previous observed inverse associations of dairy intake with systolic blood pressure and risk of hypertension were causal.Design Mendelian randomization study using the single nucleotide polymorphism rs4988235 related to lactase persistence as an instrumental variable.Setting CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) Consortium.Participants Data from 22 studies with 171 213 participants, and an additional 10 published prospective studies with 26 119 participants included in the observational analysis.Main outcome measures The instrumental variable estimation was conducted using the ratio of coefficients approach. Using meta-analysis, an additional eight published randomized clinical trials on the association of dairy consumption with systolic blood pressure were summarized.Results Compared with the CC genotype (CC is associated with complete lactase deficiency), the CT/TT genotype (TT is associated with lactose persistence, and CT is associated with certain lactase deficiency) of LCT-13910 (lactase persistence gene) rs4988235 was associated with higher dairy consumption (0.23 (about 55 g/day), 95% confidence interval 0.17 to 0.29) serving/day; Pdairy consumption was not associated with systolic blood pressure (β=1.35, 95% confidence interval -0.28 to 2.97 mm Hg for each serving/day) or risk of hypertension (odds ratio 1.04, 0.88 to 1.24). Moreover, meta-analysis of the published clinical trials showed that higher dairy intake has no significant effect on change in systolic blood pressure for interventions over one month to 12 months (intervention compared with control groups: β=-0.21, 95% confidence interval -0.98 to 0.57 mm Hg). In observational analysis, each serving/day increase in dairy consumption was associated with -0.11 (95% confidence interval -0.20 to -0.02 mm Hg; P=0.02) lower systolic blood pressure but not risk of hypertension (odds ratio 0.98, 0.97 to 1.00; P=0.11).Conclusion

  17. Microalbuminuria in patients with non-insulin-dependent diabetes mellitus relates to nocturnal systolic blood pressure.

    LENUS (Irish Health Repository)

    Mitchell, T H

    2012-02-03

    PURPOSE: Microalbuminuria predicts early mortality in non-insulin-dependent-diabetes mellitus patients (NIDDM). Our objective in the present study was to compare and assess the relationship between 24-hour, day and nocturnal ambulatory blood pressure (BP) and urinary albumin excretion rate (UAE) in microalbuminuric and normoalbuminuric NIDDM and in normal control subjects. PATIENTS AND METHODS: In the present cross-sectional study, 24 hour ambulatory BP (daytime BP and nocturnal BP) and HbA1c were compared in microalbuminuric (n = 10) and nonmicroalbuminuric NIDDM patients (n = 10) and in nondiabetic controls (n = 9). None of the patients were taking antihypertensive agents. RESULTS: In the microlbuminuric group, whereas 24 hour and daytime systolic BP differed significantly from control values (P < 0.025 and P < 0.05 respectively), there was no difference between diabetic groups. However, nocturnal systolic BP in the microalbuminuric group was significantly higher than in the normoalbuminuric diabetic patients (139 vs. 125) (P < 0.05) and a significant difference was also found between the NIDDM patients and the control group (139, 125 vs. 114) (P < 0.025). In multiple regression analysis, only nocturnal systolic BP showed a significant relationship with UAE (P < 0.05). CONCLUSIONS: We suggest that the higher nocturnal systolic blood pressure seen in our microalbuminuric NIDDM patients may contribute to the increased morbidity in this group.

  18. Association of target organ damage with 24-hour systolic and diastolic blood pressure levels and hypertension subtypes in untreated Chinese.

    Science.gov (United States)

    Wei, Fang-Fei; Li, Yan; Zhang, Lu; Xu, Ting-Yan; Ding, Feng-Hua; Staessen, Jan A; Wang, Ji-Guang

    2014-02-01

    The association of target organ damage with 24-hour systolic and diastolic blood pressure levels and ambulatory hypertension subtypes has not yet been examined in untreated Chinese patients. We measured left ventricular mass index by echocardiography (n=619), the urinary albumin:creatinine ratio (n=1047), and aortic pulse wave velocity by tonometry (n=1013) in 1047 untreated subjects (mean age, 50.6 years; 48.9% women). Normotension was a 24-hour systolic/diastolic blood pressure Hypertension subtypes were isolated diastolic hypertension and mixed systolic plus diastolic hypertension. We assessed associations of interest by multivariable-adjusted linear models. Using normotension as reference, mixed hypertension was associated with higher (P≤0.003) left ventricular mass index (+4.31 g/m(2)), urinary albumin:creatinine ratio (+1.63 mg/mmol), and pulse wave velocity (+0.76 m/s); and isolated diastolic hypertension was associated with similar left ventricular mass index and pulse wave velocity (P≥0.39), but higher urinary albumin:creatinine ratio (+1.24 mg/mmol; P=0.002). In younger participants (hypertension are major determinants of target organ damage irrespective of age and target organ, whereas 24-hour diastolic blood pressure and isolated diastolic hypertension only relate to the urinary albumin:creatinine ratio below middle age.

  19. Prognostic utility of blood pressure-adjusted global and basal systolic longitudinal strain

    Directory of Open Access Journals (Sweden)

    Isaac B Rhea

    2016-05-01

    Full Text Available Assessment of global longitudinal systolic strain (GLS and longitudinal systolic strain of the basal segments (BLS has shown prognostic value in cardiac disorders. However, strain is reduced with increased afterload. We assessed the prognostic value of GLS and BLS adjusted for afterload. GLS and BLS were determined in 272 subjects with normal ejection fraction and no known coronary disease, or significant valve disease. Systolic blood pressure (SP and diastolic blood pressure (DP obtained at the time of echocardiography were used to adjust GLS and BLS as follows: strain × SP (mmHg/120 mmHg and strain × DP (mmHg/80 mmHg. Patients were followed for cardiac events and mortality. The mean age was 53 ± 15 years and 53% had hypertension. There were 19 cardiac events and 70 deaths over a mean follow-up of 26 ± 14 months. Cox analysis showed that left ventricular mass index (P = 0.001, BLS (P < 0.001, and DP-adjusted BLS (P < 0.001 were independent predictors of cardiac events. DP-adjusted BLS added incremental value (P < 0.001 to the other two predictors and had an area under the curve of 0.838 for events. DP (P = 0.001, age (P = 0.001, ACE inhibitor use (P = 0.017, and SP-adjusted BLS (P = 0.012 were independent predictors of mortality. SP-adjusted BLS added incremental value (P = 0.014 to the other independent predictors. In conclusion, DP-adjusted BLS and SP-adjusted BLS were independent predictors of cardiac events and mortality, respectively. Blood pressure-adjusted strain added incremental prognostic value to other predictors of outcome. Introduction Assessment of global longitudinal systolic strain (GLS and basal longitudinal systolic strain (BLS have shown utility for prediction of prognosis in various cardiac disorders (1, 2, 3, 4. In some studies, longitudinal strain has been shown to be a more sensitive indicator of left ventricular (LV systolic dysfunction than traditional measures of function (5, 6. The detection of early

  20. Systolic blood pressure contributes to intracerebral haemorrhage after thrombolysis for ischemic stroke.

    Science.gov (United States)

    Perini, Francesco; De Boni, Antonella; Marcon, Michela; Bolgan, Irene; Pellizzari, Michele; Dionisio, Laura Di

    2010-10-15

    The frequency and risk factors for intracerebral haemorrhage (ICH) after ischemic stroke are well-known. ICH frequency is increased by the use of antithrombotic or thrombolytic drugs. Several experimental studies have demonstrated a relationship between ICH and hypertension after fibrinolysis, but the optimal blood pressure levels in patients treated with recombinant tissue plasminogen activator (rTPA) are as yet unknown. We evaluated the role of blood pressure in patients with ischemic stroke treated with rTPA within 3h of symptom onset. We treated 86 consecutive patients admitted to our stroke unit between 2002 and 2008 and prospectively recorded the clinical and instrumental data in our stroke registry. We evaluated haemorrhagic complications by reviewing imaging findings. Blood pressure was recorded before rTPA and at 6, 12, 18, and 32h. Total cerebral haemorrhage occurred in eleven (12.7%) patients, and symptomatic intracerebral haemorrhage occurred in seven (8.1%). We failed to find a correlation between blood pressure levels and stroke severity at admission. High blood pressure levels correlated with a worse outcome. Systolic blood pressure was significantly higher in ICH patients relative to rTPA-treated patients without haemorrhagic complications (p<0.03). This study indicates that rTPA-induced haemorrhage is influenced by systolic blood pressure. More aggressive pharmacological reduction of hypertension during fibrinolysis and the subsequent 32h may reduce this complication. Copyright 2010 Elsevier B.V. All rights reserved.

  1. Reduced effect of percutaneous renal denervation on blood pressure in patients with isolated systolic hypertension.

    Science.gov (United States)

    Ewen, Sebastian; Ukena, Christian; Linz, Dominik; Kindermann, Ingrid; Cremers, Bodo; Laufs, Ulrich; Wagenpfeil, Stefan; Schmieder, Roland E; Böhm, Michael; Mahfoud, Felix

    2015-01-01

    Renal denervation can reduce blood pressure in certain patients with resistant hypertension. The effect in patients with isolated systolic hypertension (ISH, ≥140/hypertension (CH, ≥140/≥90 mm Hg) defined as baseline office systolic blood pressure (SBP) ≥140 mm Hg despite treatment with ≥3 antihypertensive agents. Renal denervation significantly reduced office SBP and diastolic blood pressure (DBP) at 3, 6, and 12 months by 17/18/17 and 5/4/4 mm Hg in ISH and by 28/27/30 and 13/16/18 mm Hg in CH, respectively. The reduction in SBP and DBP in ISH was lower compared with patients with CH at all observed time points (P<0.05 for SBP/DBP intergroup comparison). The nonresponder rate (change in office SBP <10 mm Hg) after 6 months was 37% in ISH and 21% in CH (P<0.001). Mean 24-hour ambulatory SBP and DBP after 3, 6, and 12 months were significantly reduced by 10/13/15 and 6/6/9 mm Hg in CH, respectively. In patients with ISH the reduction in systolic ambulatory blood pressure was 4/8/7 mm Hg (P=0.032/P<0.001/P=0.009) and 3/4/2 mm Hg (P=0.08/P<0.001/P=0.130) in diastolic ambulatory blood pressure after 3, 6, and 12 months, respectively. The ambulatory blood pressure reduction was significantly lower after 3 and 12 months in SBP and after 12 months in ambulatory DBP, respectively. In conclusion, renal denervation reduces office and ambulatory blood pressure in patients with ISH. However, this reduction is less pronounced compared with patients with CH.

  2. Exposure to fipronil elevates systolic blood pressure and disturbs related biomarkers in plasma of rats.

    Science.gov (United States)

    Chaguri, Joao Leandro; Godinho, Antonio Francisco; Horta, Daniel França; Gonçalves-Rizzi, Victor Hugo; Possomato-Vieira, Jose Sergio; Nascimento, Regina Aparecida; Dias-Junior, Carlos Alan

    2016-03-01

    Recent reports show that fipronil affects non-target organisms, including environmental species populations and potentially humans. We aimed to examine if fipronil exposure affects the systolic blood pressure and related biomarkers. Thus, fipronil was orally administered to rats (30 mg/kg/day) during 15 days (Fipronil group) or physiological solution (Control group). While fipronil increased significantly the systolic blood pressure (158±13 mmHg), no significant changes were observed in Control group (127±3 mmHg). Significantly, higher levels of fipronil in plasma were observed in Fipronil group (0.46±0.09 μg/mL versus 0.17±0.11 μg/mL in Control group). Fipronil group showed lower weight gain compared with Control group. While fipronil resulted in higher concentrations of endothelin-1, reduced antioxidant capacity and lower levels of circulating matrix metalloproteinase 2 (MMP-2) and nitric oxide (NO) metabolites compared to Control group, no alteration was observed in serum biomarkers of renal and hepatic/biliary functional abilities. Therefore, this study suggests that fipronil causes hypertension and endothelin-1 plays a key role. Also, these findings suggest that reductions of both MMP-2 and NO may contribute with the elevation of systolic blood pressure observed with fipronil.

  3. Impact of Baseline Systolic Blood Pressure and Long-Term Outcomes in Patients with Advanced Chronic Systolic Heart Failure (Insights from the BEST Trial)

    OpenAIRE

    2010-01-01

    The impact of baseline systolic blood pressure (SBP) on outcomes in advanced chronic systolic heart failure (HF) patients has not been studied using propensity-matched design. Of the 2706 Beta-Blocker Evaluation of Survival Trial (BEST) participants with chronic HF, New York Heart Association class III–IV symptoms and left ventricular ejection fraction ≤35%, 1751 had SBP ≤120 (median, 108; range, 70–120) mm Hg and 955 had SBP >120 (median, 134; range 121–192) mm Hg. Propensity scores for SBP ...

  4. 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.

  5. Effect of Visit‐to‐Visit Variation of Heart Rate and Systolic Blood Pressure on Outcomes in Chronic Systolic Heart Failure: Results From the Systolic Heart Failure Treatment With the I f Inhibitor Ivabradine Trial (SHIFT) Trial

    OpenAIRE

    Böhm, Michael; Robertson, Michele; Borer, Jeffrey; Ford, Ian; Komajda, Michel; Mahfoud, Felix; Ewen, Sebastian; Swedberg, Karl; Tavazzi, Luigi

    2016-01-01

    Background Elevated resting heart rate (HR) and low systolic blood pressure (SBP) are related to poor outcomes in heart failure (HF). The association between visit‐to‐visit variation in SBP and HR and risk in HF is unknown. Methods and Results In Systolic Heart Failure Treatment with the I f inhibitor ivabradine Trial (SHIFT) patients, we evaluated relationships between mean HR, mean SBP, and visit‐to‐visit variations (coefficient of variation [CV]=SD/mean×100%) in SBP and HR (SBP‐CV and HR‐C...

  6. 数学模型模拟高血压患者对降压药物收缩压反应的探索研究%Modeling of systolic blood pressure reaction to antihypertensive agents in people with hypertension

    Institute of Scientific and Technical Information of China (English)

    吴瑛; 李一石; Bejan-Angoulvant Theodora; Gueyffier Francois

    2011-01-01

    Objective We used the individual patient data from clinical trials, pooled in the INDANA data set, to explore whether blood pressure reduction was related to the baseline individual characteristics, and quantify the potential associations. Methods We used the data from 31 140 patients with essential hypertension recruited in four randomized placebo-controlled clinical trials, MRC35-64,MRC65-74, STEP and SYST-EU. Thiazide diuretics, β-blocker, and calcium channel blocker, three of six major BP lowering drugs were analyzed. Patients were all with the same first dosage of the drug in each trial.Age, body weight, height, level of total cholesterin (TC), systolic blood pressure (SBP) and diastolic blood pressure (DBP) when initialed and at first visit of follow-up, pharmacological treatment, gender,status of smoking, history of myocardium infarction were factors taken into model. Data were managed by software SAS(R). Statistical analyses were performed with SAS(R) and R. Model was developed to evaluate the relationship between decrease of SBP and characteristics of patients. Results Initial SBP is the only modifier of treatment effect on SBP response in the 3 BP lowering drug classes (β = 0.09, 0.37 and 0. 18,respectively). Age and initial DBP were factors significantly correlated with SBP fall for diuretic (β =0. 17and 0. 14), and age was one of factors significantly correlated with SBP fall for β-blocker ( β = -0. 17).Smokers would receive less SBP fall compare to non-smokers in β-blocker active treated group (β =-2. 07). There is converse effect of age between the diuretic and β-blocker; older people seem sensitive to diuretic, while young people are sensitive to β-blocker. As to calcium channel antagonist class, body weight is another modifier ( β = 0. 06) ( All P value are 0. 000 except 0. 050 for body weight in calcium channel antagonist class). Conclusion We identified 5 significant modifiers (baseline SBP and DBP, age, smoking status and body weight

  7. Effect of Intensive Versus Standard Clinic-Based Hypertension Management on Ambulatory Blood Pressure: Results From the SPRINT (Systolic Blood Pressure Intervention Trial) Ambulatory Blood Pressure Study.

    Science.gov (United States)

    Drawz, Paul E; Pajewski, Nicholas M; Bates, Jeffrey T; Bello, Natalie A; Cushman, William C; Dwyer, Jamie P; Fine, Lawrence J; Goff, David C; Haley, William E; Krousel-Wood, Marie; McWilliams, Andrew; Rifkin, Dena E; Slinin, Yelena; Taylor, Addison; Townsend, Raymond; Wall, Barry; Wright, Jackson T; Rahman, Mahboob

    2017-01-01

    The effect of clinic-based intensive hypertension treatment on ambulatory blood pressure (BP) is unknown. The goal of the SPRINT (Systolic Blood Pressure Intervention Trial) ambulatory BP ancillary study was to evaluate the effect of intensive versus standard clinic-based BP targets on ambulatory BP. Ambulatory BP was obtained within 3 weeks of the 27-month study visit in 897 SPRINT participants. Intensive treatment resulted in lower clinic systolic BP (mean difference between groups=16.0 mm Hg; 95% confidence interval, 14.1-17.8 mm Hg), nighttime systolic BP (mean difference=9.6 mm Hg; 95% confidence interval, 7.7-11.5 mm Hg), daytime systolic BP (mean difference=12.3 mm Hg; 95% confidence interval, 10.6-13.9 mm Hg), and 24-hour systolic BP (mean difference=11.2 mm Hg; 95% confidence interval, 9.7-12.8 mm Hg). The night/day systolic BP ratio was similar between the intensive (0.92±0.09) and standard-treatment groups (0.91±0.09). There was considerable lack of agreement within participants between clinic systolic BP and daytime ambulatory systolic BP with wide limits of agreement on Bland-Altman plots. In conclusion, targeting a systolic BP of hypertension therapy on out of office BP. Further studies are needed to assess whether targeting hypertension therapy based on ambulatory BP improves clinical outcomes. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01835249. © 2016 American Heart Association, Inc.

  8. 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.

  9. Correlation between the trajectory of systolic blood pressure and new renal damage in a nonhypertensive population.

    Science.gov (United States)

    Wang, Zhi-Jun; Jia, Dao; Tian, Jun; Liu, Jie; Li, Li-Jie; Huang, Yu-Ling; Cao, Xin-Ying; Ning, Chun-Hong; Zhao, Quan-Hui; Yu, Jun-Xing; Zhang, Rui-Ying; Zhang, Ya-Jing; Gao, Jing-Sheng; Wu, Shou-Ling

    2017-10-01

    This study aims to investigate the correlation between the trajectory of systolic blood pressure (SBP) and new renal damage in a nonhypertensive population. This prospective cohort study included a total of 14 382 nonhypertensive individuals, employees of Kailuan Group of Companies, who took part in five healthy examinations in 2006-2007, 2008-2009, 2010-2011, 2012-2013, and 2014-2015, and had complete data. These individuals were divided into four groups according to the different trajectories of SBP: low-low, low-stable, middle-high, and high-high groups. The correlation between the trajectory of SBP and new renal damage in a nonhypertensive population was analyzed using a multivariate Cox's proportional hazard regression model. (a) A total of 14 382 individuals had complete data and the average age of these individuals was 44.6±10.8 years. Among these, 10 888 (75.7%) individuals were men and 3494 (24.3%) individuals were women. (b) These individuals were divided into four groups according to different trajectories of blood pressure: low-low group, accounting for 13.15% (blood pressure was low-stable group, accounting for 53.91% (blood pressure was between 115 and 116 mmHg); middle-high group, accounting for 28.77% (blood pressure was between 125 and 131 mmHg); and high-high group, accounting for 4.6% (blood pressure was between 126 and 151 mmHg). (c) With the increase in the trajectory of SBP, the detection rate of renal damage increased gradually. From the low-low group to the high-high group, the detection rates of estimated glomerular filtration rate (eGFR) less than 60 ml/min/1.73 m were 2.3, 2.4, 3.6, and 4.3%, respectively; the positive rates of urinary protein were 1.7, 2.9, 3.8, and 5.5%, respectively; and the detection rates of eGFR less than 60 ml/min/1.73 m or positive urinary protein were 4, 5.2, 7.3, and 9.3%, respectively (Plow-low group, the risk of eGFR less than 60 ml/min/1.73 m increased by nearly 1.5 times in the high

  10. An acute bout of aerobic exercise alters interarm systolic blood pressure difference.

    Science.gov (United States)

    Holmstrup, Michael E; Clarke, Melanie M; Conner, Cailin R; Jensen, Brock T

    2017-04-01

    Clinically, when a difference of at least 10 mmHg in systolic blood pressure (SBP) between arms exists, it is identified as an interarm systolic blood pressure difference (ISBPD). At rest, ISBPD is linked with hypertension, peripheral vascular disease, and increased premature mortality. Exercise may reveal underlying cardiovascular pathologies otherwise absent at rest. However, there have been no investigations to examine the effect of exercise on ISBPD. The aim of this investigation was to determine whether exercise may alter ISBPD when detected at rest or reveal ISBPD when it was not observed in the resting condition. An experienced investigator sequentially measured SBP using standard auscultation in each arm (alternating order) in 85 normotensive individuals (22±6 years, 39 male, 46 female). ISBPD was quantified before exercise (PRE). Participants then completed a three-stage protocol on a cycle ergometer. A cadence of 50 rpm was maintained at a workload of 3 (EX-3; light) and 6 (EX-6; moderate) METS and during an active recovery (REC). At each stage, SBP was measured upon achieving steady-state heart rate. A logistic regression analysis was used to determine the change in odds ratio of ISBPD when exposed to exercise. Thirteen percent (n=11) of patients presented with ISBPD during PRE and the degree of ISBPD was lower (3.81 mmHg; Pexercise attenuated the difference between interarm SBP. Moderate-intensity exercise resulted in ISBPD not otherwise present at rest.

  11. Derivation of a measure of systolic blood pressure mutability: a novel information theory-based metric from ambulatory blood pressure tests.

    Science.gov (United States)

    Contreras, Danitza J; Vogel, Eugenio E; Saravia, Gonzalo; Stockins, Benjamin

    2016-03-01

    We provide ambulatory blood pressure (BP) exams with tools based on information theory to quantify fluctuations thus increasing the capture of dynamic test components. Data from 515 ambulatory 24-hour BP exams were considered. Average age was 54 years, 54% were women, and 53% were under BP treatment. The average systolic pressure (SP) was 127 ± 8 mm Hg. A data compressor (wlzip) designed to recognize meaningful information is invoked to measure mutability which is a form of dynamical variability. For patients with the same average SP, different mutability values are obtained which reflects the differences in dynamical variability. In unadjusted linear regression models, mutability had low association with the mean systolic BP (R(2) = 0.056; P information toward diagnosis.

  12. Life course path analysis of birth weight, childhood growth, and adult systolic blood pressure

    DEFF Research Database (Denmark)

    Gamborg, Michael; Andersen, Per Kragh; Baker, Jennifer L

    2009-01-01

    regression methods. Path analysis produced easily interpretable results, and compared with standard regression methods it produced a noteworthy gain in statistical power. The effect of change in relative body size on adult blood pressure was more pronounced after age 11 years than in earlier childhood......The inverse associations between birth weight and later adverse health outcomes and the positive associations between adult body size and poor health imply that increases in relative body size between birth and adulthood may be undesirable. In this paper, the authors describe life course path...... body size, and thereby the total effect, of size and changes in size on later outcomes. Using data on childhood body size and adult systolic blood pressure from a sample of 1,284 Danish men born between 1936 and 1970, the authors compared results from path analysis with results from 3 standard...

  13. Environmental lead exposure is associated with visit-to-visit systolic blood pressure variability in the US adults.

    Science.gov (United States)

    Faramawi, Mohammed F; Delongchamp, Robert; Lin, Yu-Sheng; Liu, Youcheng; Abouelenien, Saly; Fischbach, Lori; Jadhav, Supriya

    2015-04-01

    The association between environmental lead exposure and blood pressure variability, an important risk factor for cardiovascular disease, is unexplored and unknown. The objective of the study was to test the hypothesis that lead exposure is associated with blood pressure variability. American participants 17 years of age or older from National Health and Nutrition Examination Survey III were included in the analysis. Participants' blood lead concentrations expressed as micrograms per deciliter were determined. The standard deviations of visit-to-visit systolic and diastolic blood pressure were calculated to determine blood pressure variability. Multivariable regression analyses adjusted for age, gender, race, smoking and socioeconomic status were employed. The participants' mean age and mean blood lead concentration were 42.72 years and 3.44 mcg/dl, respectively. Systolic blood pressure variability was significantly associated with environmental lead exposure after adjusting for the effect of the confounders. The unadjusted and adjusted means of visit-to-visit systolic blood pressure variability and the β coefficient of lead exposure were 3.44, 3.33 mcg/dl, β coefficient = 0.07, P environmental lead exposure and systolic blood pressure variability. Screening adults with fluctuating blood pressure for lead exposure could be warranted.

  14. Chlorthalidone Plus Amiloride Reduces the Central Systolic Blood Pressure in Stage 1 Hypertension Patients

    Science.gov (United States)

    Fernandes, Leticia Aparecida Barufi; Cestario, Elizabeth do Espirito Santo; Cosenso-Martin, Luciana Neves; Vilela-Martin, Jose Fernando; Yugar-Toledo, Juan Carlos; Fuchs, Flavio Danni

    2016-01-01

    Background Hypertension reduction strategies use blood pressure in the brachial artery as the primary endpoint. Individuals who achieve the target blood pressure reduction with antihypertensive treatment have residual cardiovascular risk attributed to the difference in pressure between the aorta and brachial artery. Antihypertensive treatment affects the intrinsic properties of the vascular wall and arterial stiffness markers and consequently the central pressure. Recent publications stress the importance of adequate control of the central compared to peripheral blood pressure. Related clinical implications suggest that individuals with normal peripheral but high central blood pressure should not receive antihypertensive drugs that act on the central pressure. Therefore, they are at greater cardiovascular risk. The aim of the study was to evaluate the effect of treatment with a thiazide diuretic versus losartan on the central blood pressure in stage 1 hypertensive patients. Methods Twenty-five patients were randomized to the chlorthalidone 25 mg/amiloride 5 mg group (q.d.) and 25 patients received losartan 50 mg (b.i.d). The central systolic blood pressure (CSBP) and augmentation index (AIx 75) were assessed using applanation tonometry. The paired t-test was used to compare the systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), pulse pressure (PP), CSBP and AIx 75 between the thiazide and losartan groups at baseline and after 6 months of treatment. Results Significant reductions in CSBP (123.3 ± 14.2 vs. 113.4 ± 111.4, P = 0.0103) and AIx 75 (87.7 ± 9.6 vs. 83.8 ± 8.9, P = 0.0289) were observed after 6 months of drug treatment with chlorthalidone 25 mg/amiloride 5 mg (q.d.). The administration of losartan 50 mg (b.i.d) did not reduce the CSBP and there were insignificant changes in the AIx 75. Conclusions Six-month treatment of chlorthalidone/amiloride but not losartan reduces the CSBP and AIx 75 in adults with stage 1

  15. Pre-dialysis systolic blood pressure-variability is independently associated with all-cause mortality in incident haemodialysis patients.

    Directory of Open Access Journals (Sweden)

    Viknesh Selvarajah

    Full Text Available Systolic blood pressure variability is an independent risk factor for mortality and cardiovascular events. Standard measures of blood pressure predict outcome poorly in haemodialysis patients. We investigated whether systolic blood pressure variability was associated with mortality in incident haemodialysis patients. We performed a longitudinal observational study of patients commencing haemodialysis between 2005 and 2011 in East Anglia, UK, excluding patients with cardiovascular events within 6 months of starting haemodialysis. The main exposure was variability independent of the mean (VIM of systolic blood pressure from short-gap, pre-dialysis blood pressure readings between 3 and 6 months after commencing haemodialysis, and the outcome was all-cause mortality. Of 203 patients, 37 (18.2% patients died during a mean follow-up of 2.0 (SD 1.3 years. The age and sex-adjusted hazard ratio (HR for mortality was 1.09 (95% confidence interval (CI 1.02-1.17 for a one-unit increase of VIM. This was not altered by adjustment for diabetes, prior cardiovascular disease and mean systolic blood pressure (HR 1.09, 95% CI 1.02-1.16. Patients with VIM of systolic blood pressure above the median were 2.4 (95% CI 1.17-4.74 times more likely to die during follow-up than those below the median. Results were similar for all measures of blood pressure variability and further adjustment for type of dialysis access, use of antihypertensives and absolute or variability of fluid intake did not alter these findings. Diastolic blood pressure variability showed no association with all cause mortality. Our study shows that variability of systolic blood pressure is a strong and independent predictor of all-cause mortality in incident haemodialysis patients. Further research is needed to understand the mechanism as this may form a therapeutic target or focus for management.

  16. Birth characteristics and risk of high systolic blood pressure in early adulthood: socioeconomic factors and familial effects.

    Science.gov (United States)

    Bergvall, Niklas; Iliadou, Anastasia; Tuvemo, Torsten; Cnattingius, Sven

    2005-09-01

    Although an inverse association between size at birth and blood pressure has been found in several studies, few studies have adjusted for the influence of socioeconomic and familial effects. We investigated whether the association between birth weight and systolic blood pressure in young men is confounded by socioeconomic factors in adolescence or familial factors (ie, common genes and shared environment). Our population-based cohort study comprised 330,768 Swedish men born between 1973 and 1981, and conscripted for military service between 1991 and 2000. The analyses of family effects were restricted to 89,856 siblings from the initial cohort. A high systolic blood pressure at conscription was defined as a systolic blood pressure >/=140 mm Hg. Birth weight for gestational age pressure (odds ratio = 1.14; 95% confidence interval = 1.07-1.22), even after adjustment for important confounders such as socioeconomic status. The increase in risk of high systolic blood pressure related to 1 standard deviation score decrease in birth weight for gestational age was similar within families (1.08; 1.04-1.12) and between families (1.05; 1.03-1.08). This study suggests that low birth weight for gestational age slightly increases the risk of high systolic blood pressure, and that the association appears not to be confounded by socioeconomic or familial effects.

  17. Validity of Some Anthropometric Indicators in the Prediction of High Systolic Blood Pressure among Indian Adolescents

    Directory of Open Access Journals (Sweden)

    Shobha Rao

    2008-01-01

    Full Text Available Background In view of the increasing prevalence of obesity in children, it is necessary to investigate the relative performance of different indicators used for its assessment and health consequences. Objectives To examine concordance between various indicators used for assessing obesity among adolescents and to examine their ability to predict risk of high systolic blood pressure. Design Cross-sectional study, from two schools catering to affluent class. Subjects Children in age 9–16 yr (n = 1146 boys and 1036 girls. Measurements Body weight, height, skinfold thickness at triceps (TSFT and body fat percent by trained investigators and blood pressure measurement by a pediatrician using sphygmomanometer. Results Prevalence of overweight was lowest with criterion of TSFT (11.7% in boys; 7.6% in girls and was highest using criterion of body fat percent (53.7% in boys and 28.4% in girls. Body mass index (BMI had high significant correlation with each of the indicator and with systolic blood pressure (SBP as well, in both sexes. All the indicators with conventional cut offs showed poor sensitivity for predicting high SBP. However, receiver operating characteristics (ROC cut-offs improved sensitivity considerably, but the values were much lower compared to conventional cut-offs. Conclusions There is considerable disparity in the estimates of overweight children obtained by different indicators. Lower values of ROC cut-offs highlights the need for population specific customized classification systems for assessing obesity in view of the probable population differences in relative risks of non-communicable adult diseases.

  18. Validity of Some Anthropometric Indicators in the Prediction of High Systolic Blood Pressure Among Indian Adolescents

    Directory of Open Access Journals (Sweden)

    Shobha Rao

    2008-01-01

    Full Text Available Background: In view of the increasing prevalence of obesity in children, it is necessary to investigate the relative performance of different indicators used for its assessment and health consequences.Objectives: To examine concordance between various indicators used for assessing obesity among adolescents and to examine their ability to predict risk of high systolic blood pressure.Design: Cross-sectional study, from two schools catering to affluent class.Subjects: Children in age 9–16 yr (n = 1146 boys and 1036 girls.Measurements: Body weight, height, skinfold thickness at triceps (TSFT and body fat percent by trained investigators and blood pressure measurement by a pediatrician using sphygmomanometer.Results: Prevalence of overweight was lowest with criterion of TSFT (11.7% in boys; 7.6% in girls and was highest using criterion of body fat percent (53.7% in boys and 28.4% in girls. Body mass index (BMI had high significant correlation with each of the indicator and with systolic blood pressure (SBP as well, in both sexes. All the indicators with conventional cut offs showed poor sensitivity for predicting high SBP. However, receiver operating characteristics (ROC cut-offs improved sensitivity considerably, but the values were much lower compared to conventional cut-offs.Conclusions: There is considerable disparity in the estimates of overweight children obtained by different indicators. Lower values of ROC cut-offs highlights the need for population specific customized classification systems for assessing obesity in view of the probable population differences in relative risks of non-communicable adult diseases.

  19. Optimal Systolic Blood Pressure Target After SPRINT: Insights from a Network Meta-Analysis of Randomized Trials.

    Science.gov (United States)

    Bangalore, Sripal; Toklu, Bora; Gianos, Eugenia; Schwartzbard, Arthur; Weintraub, Howard; Ogedegbe, Gbenga; Messerli, Franz H

    2017-06-01

    The optimal on-treatment blood pressure (BP) target has been a matter of debate. The recent SPRINT trial showed significant benefits of a BP target of targets. Trial arms were grouped into 5 systolic BP target categories: 1) targets. However, the point estimate favored lower BP targets (targets (targets of target. There was a significant increase in serious adverse effects with systolic BP targets of target for the outcome of serious adverse effects. Cluster plots for combined efficacy and safety showed that a systolic BP target of target of <130 mm Hg achieved optimal balance between efficacy and safety. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Systolic and diastolic changes in human coronary blood flow during Valsalva manoeuvre.

    Science.gov (United States)

    Federici, A; Ciccone, M; Gattullo, D; Losano, G

    2000-01-01

    Valsalva manoeuvre is reported to be sometimes successful for the relief of angina pectoris. The present study investigated how haemodynamic changes produced by Valsalva manoeuvre can interact to improve the relationship between cardiac work and coronary blood flow. Ten male subjects aged 53 +/- 12 years (SD) were considered. Blood velocity in the internal mammary artery, previously anastomosed to the left descending coronary artery, was studied with Doppler technique. The subjects performed Valsalva manoeuvres by expiring into a tube connected to a mercury manometer, to develop a pressure of 40 mmHg. The arterial blood pressure curve was continuously monitored with a Finapres device from a finger of the left hand. During expiratory effort, an increase in heart rate and a decrease in arterial pulse pressure were followed by a more delayed and progressive increase in mean and diastolic pressures. Systolic blood velocity markedly decreased along with the reduction in pulse pressure and increase in heart rate. By contrast, diastolic and mean coronary blood velocities did not show any significant change. Since it is known that the Valsalva manoeuvre strongly reduces stroke volume and cardiac output, it is likely that a reduction in cardiac work also takes place. Since in diastole, i.e. when the myocardial wall is better perfused, coronary blood velocity did not show any significant reduction, it is likely that unchanged perfusion in the presence of reduced cardiac work is responsible for the relief from angina sometimes observed during Valsalva manoeuvre. It is also likely that the increase in heart rate prevents the diastolic and mean blood coronary velocity from decreasing during the expiratory strain, when an increased sympathetic discharge could cause vasoconstriction through the stimulation of the coronary alpha-receptors.

  1. NSAID-antihypertensive drug interactions: which outpatients are at risk for a rise in systolic blood pressure?

    NARCIS (Netherlands)

    Floor-Schreudering, A.; Smet, P.A.G.M. de; Buurma, H.; Kramers, C.; Tromp, P.C.; Belitser, S.V.; Bouvy, M.L.

    2015-01-01

    BACKGROUND: Management guidelines for drug-drug interactions between non-steroidal anti-inflammatory drugs (NSAIDs) and antihypertensives recommend blood pressure monitoring in hypertensive patients. We measured the short-term effect of initiating NSAIDs on systolic blood pressure (SBP) in users of

  2. NSAID-antihypertensive drug interactions: Which outpatients are at risk for a rise in systolic blood pressure?

    NARCIS (Netherlands)

    Floor-Schreudering, Annemieke; De Smet, Peter Agm; Buurma, Henk; Kramers, Cornelis; Tromp, P. Chris; Belitser, Svetlana V.; Bouvy, Marcel L.

    2015-01-01

    Background: Management guidelines for drug-drug interactions between non-steroidal anti-inflammatory drugs (NSAIDs) and antihypertensives recommend blood pressure monitoring in hypertensive patients. We measured the short-term effect of initiating NSAIDs on systolic blood pressure (SBP) in users of

  3. NSAID-antihypertensive drug interactions: Which outpatients are at risk for a rise in systolic blood pressure?

    NARCIS (Netherlands)

    Floor-Schreudering, Annemieke; De Smet, Peter Agm; Buurma, Henk; Kramers, Cornelis; Tromp, P. Chris; Belitser, Svetlana V.; Bouvy, Marcel L.

    2015-01-01

    Background: Management guidelines for drug-drug interactions between non-steroidal anti-inflammatory drugs (NSAIDs) and antihypertensives recommend blood pressure monitoring in hypertensive patients. We measured the short-term effect of initiating NSAIDs on systolic blood pressure (SBP) in users of

  4. NSAID-antihypertensive drug interactions: which outpatients are at risk for a rise in systolic blood pressure?

    NARCIS (Netherlands)

    Floor-Schreudering, A.; Smet, P.A.G.M. de; Buurma, H.; Kramers, C.; Tromp, P.C.; Belitser, S.V.; Bouvy, M.L.

    2015-01-01

    BACKGROUND: Management guidelines for drug-drug interactions between non-steroidal anti-inflammatory drugs (NSAIDs) and antihypertensives recommend blood pressure monitoring in hypertensive patients. We measured the short-term effect of initiating NSAIDs on systolic blood pressure (SBP) in users of

  5. Serum proatrial natriuretic peptide does not increase with higher systolic blood pressure in obese men

    DEFF Research Database (Denmark)

    Asferg, Camilla L; Andersen, Ulrik B; Linneberg, Allan;

    2017-01-01

    OBJECTIVE: Obese persons have low circulating natriuretic peptide (NP) concentrations. It has been proposed that this 'natriuretic handicap' could play a role in obesity-related hypertension. The normal physiological response of the NP system to an increase in blood pressure (BP) is an increase...... vs 149.0±7.7 mm Hg in fourth quartile, pnegatively associated with systolic ABP (ß=-0.32, p=0.004) and with diastolic ABP (ß=-0.45, p...: Contrary to known physiological BP responses, MR-proANP was negatively associated with ABP in our study. This suggests that a low amount of circulating NPs could play a role in the early stage of obesity-related hypertension....

  6. Effect of Visit-to-Visit Variation of Heart Rate and Systolic Blood Pressure on Outcomes in Chronic Systolic Heart Failure: Results From the Systolic Heart Failure Treatment With the If Inhibitor Ivabradine Trial (SHIFT) Trial.

    Science.gov (United States)

    Böhm, Michael; Robertson, Michele; Borer, Jeffrey; Ford, Ian; Komajda, Michel; Mahfoud, Felix; Ewen, Sebastian; Swedberg, Karl; Tavazzi, Luigi

    2016-02-12

    Elevated resting heart rate (HR) and low systolic blood pressure (SBP) are related to poor outcomes in heart failure (HF). The association between visit-to-visit variation in SBP and HR and risk in HF is unknown. In Systolic Heart Failure Treatment with the If inhibitor ivabradine Trial (SHIFT) patients, we evaluated relationships between mean HR, mean SBP, and visit-to-visit variations (coefficient of variation [CV]=SD/mean×100%) in SBP and HR (SBP-CV and HR-CV, respectively) and primary composite endpoint (cardiovascular mortality or HF hospitalization), its components, all-cause mortality, and all-cause hospitalization. High HR and low SBP were closely associated with risk for primary endpoint, all-cause mortality, and HF hospitalization. The highest number of primary endpoint events occurred in the highest HR tertile (38.8% vs 16.4% lowest tertile; PHeart Association, Inc., by Wiley Blackwell.

  7. Systolic Blood Pressure Variability is a Novel Risk Factor for Rebleeding in Acute Subarachnoid Hemorrhage

    Science.gov (United States)

    Lin, Qing-Song; Ping-Chen; Lin, Yuan-Xiang; Lin, Zhang-Ya; Yu, Liang-Hong; Dai, Lin-Sun; Kang, De-Zhi

    2016-01-01

    Abstract Rebleeding of an aneurysm is a major cause of morbidity and mortality after subarachnoid hemorrhage (SAH). Whereas numerous studies have demonstrated predictors of rebleeding and effect of systolic blood pressure variability (SBPV) on stroke, few data on the association between SBPV and rebleeding. Here, we sought to identify the effect of SBPV on rebleeding in acute aneurysmal SAH. Case–control study. From January 2010 to June 2015, 612 patients with aneurysmal SAH were enrolled in our tertiary care medical center. Main outcome measures: Consecutive patients with acute (<3 days from ictus) aneurismal rebleeding or repair or death were retrospectively included. Antihypertensive therapy based on a predefined standardized protocol was prescribed to lower and maintain SBP between 120 and 160 mm Hg. SBP was measured hourly until a censoring event occurred. SBPV was determined as standard deviation (SD) and successive variation (SV). Binary logistic regression was used to assess the association between SBPV and rebleeding. Rebleeding occurred in 61 (10.0%) of the 612 patients. We identified 47 acute rebleeding as cases and 382 early repair or early death as controls. On binary logistic regression analysis, rebleeding was associated with the SD of SBP (odds ratio [OR], 1.254; 95% confidence interval [CI], 1.131–1.391; P < 0.001) and the SV of SBP (OR, 1.131; 95% CI, 1.039–1.231; P = 0.004). No significant difference was seen between rebleeding and mean systolic blood pressure (MSBP). SBPV is associated with increased rates of acute aneurysmal rebleeding. Further prospective research is warranted to confirm that SBP stability prevents acute aneurysm rebleeding. PMID:26986118

  8. 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.

  9. More accurate systolic blood pressure measurement is required for improved hypertension management: a perspective

    Directory of Open Access Journals (Sweden)

    Nitzan M

    2017-07-01

    Full Text Available Meir Nitzan,1 Itzchak Slotki,2 Linda Shavit2 1Department of Applied Physics/Electro-Optics, Jerusalem College of Technology, 2Department of Nephrology, Shaare Zedek Medical Center, Jerusalem, Israel Abstract: The commonly used techniques for systolic blood pressure (SBP and diastolic blood pressure (DBP measurement are the auscultatory Korotkoff-based sphygmomanometry and oscillometry. The former technique is relatively accurate but is limited to a physician’s office because its automatic variant is subject to noise artifacts. Consequently, the Korotkoff-based measurement overestimates the blood pressure in some patients due to white coat effect, and because it is a single measurement, it cannot properly represent the variable blood pressure. Automatic oscillometry can be used at home by the patient and is preferred even in clinics. However, the technique’s accuracy is low and errors of 10–15 mmHg are common. Recently, we have developed an automatic technique for SBP measurement, based on an arm pressure cuff and a finger photoplethysmographic probe. The technique was found to be significantly more accurate than oscillometry, and comparable to the Korotkoff-based technique, the reference-standard for non-invasive blood pressure measurements. The measurement of SBP is a mainstay for the diagnosis and follow-up of hypertension, which is a major risk factor for several adverse events, mainly cardiovascular. Lowering blood pressure evidently reduces the risk, but excessive lowering can result in hypotension and consequently hypoperfusion to vital organs, since blood pressure is the driving force for blood flow. Erroneous measurement by 10 mmHg can lead to a similar unintended reduction of SBP and may adversely affect patients treated to an SBP of 120–130 mmHg. In particular, in elderly patients, unintended excessive reduction of blood pressure due to inaccurate SBP measurement can result in cerebral hypoperfusion and consequent cognitive

  10. Systolic blood pressure, arterial rigidity, and risk of stroke. The Framingham study.

    Science.gov (United States)

    Kannel, W B; Wolf, P A; McGee, D L; Dawber, T R; McNamara, P; Castelli, W P

    1981-03-27

    Based on prospective data from the Framingham study relating systolic pressure, diastolic pressure, age, and pulse-wave configuration to future stroke incidence, it would appear that isolated systolic hypertension predisposes to stroke independent of arterial rigidity. The prevalence of isolated systolic hypertension increased with age and with the degree of blunting of the dicrotic notch in the pulse wave. Subjects with isolated systolic hypertension experienced two to four times as many strokes as did normotensive persons. While diastolic pressure is related to stroke incidence, in the subject with systolic hypertension, the diastolic component adds little to risk assessment and in men, in this subgroup, appears unrelated to stroke incidence.

  11. Efficacy of combination therapy with amlodipine besylate/benazepril hydrochloride for lowering systolic blood pressure in stage 2 hypertension.

    Science.gov (United States)

    Neutel, Joel M; Smith, David H G; Weber, Michael A; Schofield, Lesley; Purkayastha, Das; Gatlin, Marjorie

    2006-01-01

    The Systolic Evaluation of Lotrel Efficacy and Comparative Therapies (SELECT) study compared daily treatment with combination amlodipine besylate/benazepril hydrochloride 5/20 mg, amlodipine besylate 5 mg, and benazepril hydrochloride 20 mg in 505 patients aged 55 years of age or older with stage 2 hypertension (systolic blood pressure [BP] > or =160 and or =60 and < or =100 mm Hg). BP and pulse pressure were assessed by conventional office BP measurements and 24-hour ambulatory BP monitoring. In this analysis, combination therapy was associated with significantly greater reductions in mean 24-hour BP, pulse pressure, and mean ambulatory BP during various time intervals compared with either monotherapy in the intent-to-treat population, in those with isolated and predominantly systolic hypertension, and in dippers and nondippers. Adverse event rates were low and similar in all treatment groups. This study demonstrated that combination therapy is superior to monotherapy in older patients with stage 2 systolic hypertension and is well tolerated.

  12. Prediction of systolic blood pressure using peripheral pulse palpation in cats.

    Science.gov (United States)

    Reineke, Erica L; Rees, Colleen; Drobatz, Kenneth J

    2016-01-01

    To evaluate the ability of peripheral pulse palpation to predict systolic blood pressure (SBP) in cats presenting as emergencies. Prospective observational study performed over an 8-month period. University veterinary teaching hospital. One hundred two cats presenting to the emergency service. Eligibility for inclusion in the study included a physical examination and a SBP via Doppler technique performed prior to treatment. None. Femoral and metatarsal pulses were digitally palpated and the quality of the pulses was assessed as either strong, moderate, poor, or absent. A concurrent SBP was also recorded. The median SBP for all cats was 92.5 mm Hg (range, 30-240 mm Hg). Femoral pulse quality was found to strongly correlate with the admission SBP (P cats with either absent or strong pulses was significantly different (P Cats with absent metatarsal and femoral pulses had a median SBP of 30 mm Hg (range, 30-105 mm Hg), whereas cats with strong metatarsal pulses had a median SBP of 135 mm Hg (range, 58-210 mm Hg). Absent metatarsal pulses correctly identified cats with a blood pressure of 75 mm Hg or less 84% the time (area under the curve: 0.89, confidence interval 0.81, 0.97). In cats, peripheral pulse quality assessment by emergency room veterinarians correlates with SBP. With progressive decreases in blood pressure, metatarsal pulses will disappear and it is only with severe hypotension that femoral pulses are absent. An assessment of both dorsal metatarsal pulse and femoral pulse quality during triage may be useful in identifying abnormalities in blood pressure. © Veterinary Emergency and Critical Care Society 2015.

  13. Heart Rate and Systolic Blood Pressure Variability on Recently Diagnosed Diabetics

    Directory of Open Access Journals (Sweden)

    Anaclara Michel-Chávez

    2015-01-01

    Full Text Available Background: Diabetes affects approximately 250 million people in the world. Cardiovascular autonomic neuropathy is a common complication of diabetes that leads to severe postural hypotension, exercise intolerance, and increased incidence of silent myocardial infarction. Objective: To determine the variability of heart rate (HR and systolic blood pressure (SBP in recently diagnosed diabetic patients. Methods: The study included 30 patients with a diagnosis of type 2 diabetes of less than 2 years and 30 healthy controls. We used a Finapres® device to measure during five minutes beat-to-beat HR and blood pressure in three experimental conditions: supine position, standing position, and rhythmic breathing at 0.1 Hz. The results were analyzed in the time and frequency domains. Results: In the HR analysis, statistically significant differences were found in the time domain, specifically on short-term values such as standard deviation of NN intervals (SDNN, root mean square of successive differences (RMSSD, and number of pairs of successive NNs that differ by more than 50 ms (pNN50. In the BP analysis, there were no significant differences, but there was a sympathetic dominance in all three conditions. The baroreflex sensitivity (BRS decreased in patients with early diabetes compared with healthy subjects during the standing maneuver. Conclusions: There is a decrease in HR variability in patients with early type 2 diabetes. No changes were observed in the BP analysis in the supine position, but there were changes in BRS with the standing maneuver, probably due to sympathetic hyperactivity.

  14. Efficacy and duration of benazepril plus amlodipine or hydrochlorothiazide on 24-hour ambulatory systolic blood pressure control.

    Science.gov (United States)

    Jamerson, Kenneth A; Devereux, Richard; Bakris, George L; Dahlöf, Björn; Pitt, Bertram; Velazquez, Eric J; Weir, Matthew; Kelly, Roxzana Y; Hua, Tsushung A; Hester, Allen; Weber, Michael A

    2011-02-01

    The combination of benazepril plus amlodipine was shown to be more effective than benazepril plus hydrochlorothiazide in reducing cardiovascular events in the Avoiding Cardiovascular Events through Combination Therapy in Patients Living with Systolic Hypertension (ACCOMPLISH) trial. There was a small difference in clinic systolic blood pressure between the treatment arms favoring benazepril plus amlodipine. Ambulatory blood pressure monitoring provides a more rigorous estimate of blood pressure effects. A subset of 573 subjects underwent ambulatory blood pressure monitoring during year 2. Readings were obtained every 20 minutes during a 24-hour period. Between-treatment differences (benazepril plus amlodipine versus benazepril plus hydrochlorothiazide) in mean values were analyzed using ANOVA. Treatment comparisons with respect to categorical variables were made using Pearson's χ². At year 2, the treatment groups did not differ significantly in 24-hour mean daytime or nighttime blood pressures (values of 123.9, 125.9, and 118.1 mm Hg for benazepril plus amlodipine group versus 122.3, 124.1, and 116.9 for the benazepril plus hydrochlorothiazide group), with mean between-group differences of 1.6, 1.8, and 1.2 mm Hg, respectively. Blood pressure control rates (24-hour mean systolic blood pressure amlodipine rather than hydrochlorothiazide shown in the ACCOMPLISH trial was not caused by differences in blood pressure, but instead intrinsic properties (metabolic or hemodynamic) of the combination therapies.

  15. Effect of home blood pressure telemonitoring with self-care support on uncontrolled systolic hypertension in diabetics.

    Science.gov (United States)

    Logan, Alexander G; Irvine, M Jane; McIsaac, Warren J; Tisler, Andras; Rossos, Peter G; Easty, Anthony; Feig, Denice S; Cafazzo, Joseph A

    2012-07-01

    Lowering blood pressure reduces cardiovascular risk, yet hypertension is poorly controlled in diabetic patients. In a pilot study we demonstrated that a home blood pressure telemonitoring system, which provided self-care messages on the smartphone of hypertensive diabetic patients immediately after each reading, improved blood pressure control. Messages were based on care paths defined by running averages of transmitted readings. The present study tests the system's effectiveness in a randomized, controlled trial in diabetic patients with uncontrolled systolic hypertension. Of 244 subjects screened for eligibility, 110 (45%) were randomly allocated to the intervention (n = 55) or control (n = 55) group, and 105 (95.5%) completed the 1-year outcome visit. In the intention-to-treat analysis, mean daytime ambulatory systolic blood pressure, the primary end point, decreased significantly only in the intervention group by 9.1 ± 15.6 mmHg (SD; P blood pressure telemonitoring combined with automated self-care support reduced the blood pressure of diabetic patients with uncontrolled systolic hypertension and improved hypertension control. Home blood pressure monitoring alone had no effect on blood pressure. Promoting patient self-care may have negative psychological effects.

  16. Predictors of high central blood pressure in young with isolated systolic hypertension

    Directory of Open Access Journals (Sweden)

    Radchenko GD

    2016-08-01

    Full Text Available G D Radchenko, O O Torbas, Yu M Sirenko State Institute National Scientific Center, M.D. Strazhesko Institute of Cardiology, National Academy of Medical Science, Kyiv, Ukraine Objective: According to the European Society of Cardiology/European Society of Hypertension 2013 guidelines, evaluation of aortic blood pressure (BP is needed in young with isolated systolic hypertension (ISH, but using special devices is not common, especially in Ukraine, where only a few centers have these devices. The purpose of our study was to identify the simple clinical predictors for differentiation (with or without elevated aortic systolic BP [SBP] of the young with ISH without the need for further extensive work-up. Patients and methods: The study included 44 young men (mean age: 32.2±1.3 years with office SBP ≥140 mmHg and office diastolic BP (DBP <90 mmHg (average: 153.4±2.1 mmHg and 83.4±1.7 mmHg, respectively. The following procedures were performed in all the subjects: body weight and height evaluation; measurement of office SBP, DBP, and heart rate; ambulatory BP monitoring; measurement of pulse wave velocity in arteries of elastic and muscle types and central SBP (cSBP; biochemical blood tests; electrocardiography; echocardiography; and carotid ultrasound investigations. Step-by-step multifactor regression analyses were used for finding the predictors of high cSBP. Results: Depending on the cSBP level, all the patients were divided into two groups: first group (n=17, subjects with normal cSBP, and second group (n=27, subjects with elevated cSBP. Patients in the second group were significantly older, with less height and higher body mass index; they had significantly higher levels of office SBP and DBP. Characteristics of target organ damage were within normal limits in both groups and did not differ significantly. Only pulse wave velocity in arteries of elastic type was significantly higher in the second group. The independent predictors of

  17. Effect of tender coconut water on systolic and diastolic blood pressure in prehypertensive women

    Directory of Open Access Journals (Sweden)

    Farapti Farapti

    2014-02-01

    . Dietary intakes of high potassium will decrease blood pressure (BP. Tender coconut water (TCW is a typical drink high in potassium. This study aimed to investigate the effect of TCW on BP in female teachers and employees prehypertension. Methods: The research was a parallel single blind randomized clinical trial. A total of 32 female prehypertension subjects aged 25-44 years. The subjects were selected using certain criteria and randomly allocated to one of two groups using block randomized, 16 subjects each. The treatment group received TCW 300 ml twice daily for 14 days and nutritional counseling, and the control group received water 300 ml twice daily for 14 days and nutritional counseling. Assessment of BP was done on day 0, day 8, and day 15. Statistical analysis were done using t-test and Mann-Whitney test. Results: Mean dietary intakes of potassium were 1420.28±405.54 mg/day or 30.22±8.63% compared to Recommended Dietary Allowance (RDA. During treatment period, potassium intake increased significantly in the treatment group. There were decreased BP in both groups, which were greater in the treatment group, but not statistically significant different (P > 0.05. The mean decrease of systolic BP was significant in treatment group (P = 0.031, meanwhile the mean decrease of diastolic BP was not significant (P=0.134. Conclusion: Tender coconut water 300 ml twice daily for 14 consecutive days has tendency to decrease systolic BP, but not diastolic blood pressure. (Health Science Indones 2013;2: 64-8Key words: coconut water, systolic and diastolic blood pressure

  18. Effect of tender coconut water on systolic and diastolic blood pressure in prehypertensive women

    Directory of Open Access Journals (Sweden)

    Farapti Farapti

    2014-02-01

    . Dietary intakes of high potassium will decrease blood pressure (BP. Tender coconut water (TCW is a typical drink high in potassium. This study aimed to investigate the effect of TCW on BP in female teachers and employees prehypertension. Methods: The research was a parallel single blind randomized clinical trial. A total of 32 female prehypertension subjects aged 25-44 years. The subjects were selected using certain criteria and randomly allocated to one of two groups using block randomized, 16 subjects each. The treatment group received TCW 300 ml twice daily for 14 days and nutritional counseling, and the control group received water 300 ml twice daily for 14 days and nutritional counseling. Assessment of BP was done on day 0, day 8, and day 15. Statistical analysis were done using t-test and Mann-Whitney test. Results: Mean dietary intakes of potassium were 1420.28±405.54 mg/day or 30.22±8.63% compared to Recommended Dietary Allowance (RDA. During treatment period, potassium intake increased significantly in the treatment group. There were decreased BP in both groups, which were greater in the treatment group, but not statistically significant different (P > 0.05. The mean decrease of systolic BP was significant in treatment group (P = 0.031, meanwhile the mean decrease of diastolic BP was not significant (P=0.134. Conclusion: Tender coconut water 300 ml twice daily for 14 consecutive days has tendency to decrease systolic BP, but not diastolic blood pressure. (Health Science Indones 2013;2: 64-8Key words: coconut water, systolic and diastolic blood pressure

  19. Phenomenon of declining blood pressure in elderly - high systolic levels are undervalued with Korotkoff method

    Directory of Open Access Journals (Sweden)

    Elmståhl Sölve

    2011-10-01

    Full Text Available Abstract Background Systolic blood pressure (SBP decline has been reported in octogenarians. The aim was to study if it could be observed while measuring SBP with two methods: Korotkoff (K-BP and Strain-Gauge-Finger-Pletysmography (SG-BP, and which of them were more reliable in expressing vascular burden. Methods A cohort of 703 men from a population of Malmö, Sweden, were included in "Men born in 1914-study" and followed-up at ages: 68 and 81 years. 176 survivors were examined with K-BP and SG-BP at both ages, and 104 of them with Ambulatory Blood Pressure at age 81/82. Ankle Brachial Index (ABI was measured on both occasions, and Carotid Ultrasound at age 81. Results From age 68 to 81, mean K-BP decreased in the cohort with mean 8.3 mmHg, while SG-BP increased with 13.4 mmHg. K-BP decreased in 55% and SG-BP in 31% of the subjects. At age 81, K-BP was lower than SG-BP in 72% of subjects, and correlated to high K-BP at age 68 (r = --.22; p Conclusion In contrast to K-BP, values of SG-BP in octogenarians strongly correlated with Ambulatory Blood Pressure. The SG-BP decline in the last decade was rare, and increasing SG-BP better than K-BP reflected advanced atherosclerosis. It should be aware, that K-BP underdetected 46% of subjects with SG-BP equal/higher than 140 mmHg at age 81, which may lead to biased associations with risk factors due to differential misclassification by age.

  20. Mozart, but not the Beatles, reduces systolic blood pressure in patients with myocardial infarction.

    Science.gov (United States)

    Gruhlke, Luiza Carolina; Patrício, Marcelo Coelho; Moreira, Daniel Medeiros

    2015-12-01

    Music reduces systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) in various clinical situations, but it is unclear whether these changes occur in post-infarction patients. The aim is to evaluate the effects of music on patients with acute myocardial infarction (MI). We evaluated patients with MI and we measured SBP, DBP, HR and double product (DP) two times before the intervention and one time every fifteen minutes with an ambulatory blood pressure monitor. We divided the patients into 3 groups: a group listening to music by Mozart; another listening to a Beatles collection and a third one listening to the radio news. Outcomes were the change in mean SBP, DBP, HR and DP with intervention. We enrolled 60 patients (20 in each group). SBP was significantly reduced in the Mozart group (variation of –7.2 ± 8.5 mmHg) compared to the Beatles group (–1.3 ± 6.2 mmHg) (P = 0.021) and the radio news group (0.6 ± 8.7 mmHg) (P = 0.003). DP was significantly reduced in the Mozart group compared with the News group (–668.5 ± 773.2 vs 31.6 ± 722.1 mmHg) (P = 0.006). There were no differences in DBP and HR. Patients with MI who listened Mozart had a reduction in SBP and DP compared to those who listened to the Beatles or the news.

  1. Excess heart rate and systolic blood pressure during psychological stress in relation to metabolic demand in adolescents

    Science.gov (United States)

    Cardiovascular responses during exercise are matched to the increased metabolic demand, but this may not be the case during psychological stress. No studies to date have tested this hypothesis in youth. Fifty-four youth, ages 13-16 years completed two visits. Heart rate (HR), systolic blood pressu...

  2. Safety and Feasibility of Achieving Lower Systolic Blood Pressure Goals in Persons With Type 2 Diabetes: The SANDS Trial

    Science.gov (United States)

    Weir, Matthew R.; Yeh, Fawn; Silverman, Angela; Devereux, Richard B.; Galloway, James M.; Henderson, Jeffrey A.; Howard, William J.; Russell, Marie; Wilson, Charlton; Ratner, Robert; Sorkin, John; Umans, Jason; Fleg, Jerome L.; Stylianou, Mario; Lee, Elisa; Howard, Barbara V.

    2009-01-01

    The Stop Atherosclerosis in Native Diabetics Study (SANDS) was a randomized open-label clinical trial in type 2 diabetics designed to examine the effects of intensive reduction of blood pressure, aggressive vs standard goals (≤115 / 75 mm Hg vs ≤130 / 80 mm Hg), and low-density lipoprotein (LDL) cholesterol on the composite outcome of change in carotid intimal-medial thickness and cardiovascular events. The study demonstrated that in conjunction with a lower LDL cholesterol target of 70 mg/ dL, aggressive systolic blood pressure–lowering resulted in a reduction in carotid intimal-medial thickness and left ventricular mass without measurable differences in cardiovascular events. The blood pressure treatment algorithm included renin-angiotensin system blockade, with other agents added if necessary. The authors conclude that both standard and more aggressive systolic blood pressure reduction can be achieved with excellent safety and good tolerability in patients with type 2 diabetes mellitus. PMID:19817934

  3. Indexes of hemodynamics in a dosage of physical activity in girls against the background of low systolic blood pressure

    OpenAIRE

    Levchenko V. A.

    2015-01-01

    Purpose: to examine the state of hemodynamics, blood oxygenation levels in girls with hypotensive type neurodystonia in a dosed physical load. Material : The study involved 59 women with hypotensive type neurodystonia aged 18-19 years and 14 healthy women the same age. Results : It was found that the girls on the background of low systolic blood pressure observed early hemodynamic response from the very first steps (25-50 W) bicycle stress test in the form of increased heart rate, stroke volu...

  4. 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.

  5. Systolic blood pressure and mortality after stroke: too low, no go?

    Science.gov (United States)

    Lin, Michelle P; Ovbiagele, Bruce; Markovic, Daniela; Towfighi, Amytis

    2015-05-01

    Recent studies suggest a J-shaped association between systolic blood pressure (SBP) and cardiovascular events. The optimal SBP target after stroke remains unknown. We assessed the link between SBP and mortality after stroke. We included adults (≥20 years) with self-reported stroke who participated in the National Health and Nutrition Examination Surveys 1998 to 2004, with mortality assessment in 2006. Baseline SBP was categorized as low to normal (low to normal, 31% had normal, and 50% had high SBP. Two years after assessment, the low to normal SBP group tended to have the highest cumulative all-cause mortality (11.5%), compared with mortality rates of 8.5% and 7.5% in the normal and high SBP groups, respectively. Similar patterns were seen with vascular mortality. After adjusting for covariates, compared with the high SBP group, the low to normal group had higher all-cause mortality (adjusted hazard ratio, 1.96; 95% confidence interval, 1.13-3.39; P=0.017) and trended toward higher vascular mortality (adjusted hazard ratio, 2.08; 95% confidence interval, 0.93-4.68; P=0.075). Compared with the normal BP group, the risk of all-cause and vascular mortality trended higher in low to normal BP group but did not achieve statistical significance. After stroke, compared with SBP in the high range, low to normal SBP is associated with poorer mortality outcomes. © 2015 American Heart Association, Inc.

  6. Fluctuation in systolic blood pressure is a major systemic risk factor for development of primary open-angle glaucoma

    Science.gov (United States)

    Lee, Na Young; Jung, Younhea; Han, Kyungdo; Park, Chan Kee

    2017-01-01

    We evaluated the risk of development of primary open-angle glaucoma (POAG) in terms of variability in BP using a nationwide, population-based, 11-year longitudinal study using the Korean National Health Insurance Research Database. We included patients who underwent health care examinations more than twice between January 2002 and December 2006. We divided all subjects by the quartiles of variability in systolic blood pressure (SBP), diastolic blood pressure (DBP), and the difference between SBP and DBP. Of the total of 80,021 included subjects, 910 were diagnosed with POAG between January 2007 and December 2013. Both the Kaplan-Meier survival curves and log-rank test data indicated that patients with higher-level BP variability developed POAG significantly more frequently than did patients with lower-level variability (P < 0.001). On multivariate Cox’s regression modeling including gender, age, sex, household income, smoking status, level of alcohol intake, extent of exercise, diabetes mellitus status, dyslipidemia status, SBP, and DBP; the hazard ratios among the highest and lowest quartiles of SD SBP and CV SBP were 1.256 and 1.238, respectively. Our findings suggest that subjects in the highest quartile of SBP variability were significantly more likely to develop POAG in our population-based sample of Korean adults. PMID:28262703

  7. Pre-Dialysis Systolic Blood Pressure-Variability Is Independently Associated with All-Cause Mortality in Incident Haemodialysis Patients: e86514

    National Research Council Canada - National Science Library

    Viknesh Selvarajah; Laura Pasea; Sanjay Ojha; Ian B Wilkinson; Laurie A Tomlinson

    2014-01-01

    .... The main exposure was variability independent of the mean (VIM) of systolic blood pressure from short-gap, pre-dialysis blood pressure readings between 3 and 6 months after commencing haemodialysis, and the outcome was all-cause mortality...

  8. Effect of ascorbic acid supplementation on nitric oxide metabolites and systolic blood pressure in rats exposed to lead.

    Science.gov (United States)

    Mohammad, Amani; Ali, Noroozzadeh; Reza, Badalzadeh; Ali, Khoshbaten

    2010-04-01

    Extended exposure to low levels of lead causes high blood pressure in human and laboratory animals. The mechanism is not completely recognized, but it is relatively implicated with generation of free radicals, oxidant agents such as ROS, and decrease of available nitric oxide (NO). In this study, we have demonstrated the effect of ascorbic acid as an antioxidant on nitric oxide metabolites and systolic blood pressure in rats exposed to low levels of lead. The adult male Wistar rats weighing 200-250 g were divided into four groups: control, lead acetate (receiving 100 ppm lead acetate in drinking water), lead acetate plus ascorbic acid (receiving 100 ppm lead acetate and 1 g/l ascorbic acid in drinking water), and ascorbic acid (receiving 1 g/l ascorbic acid in drinking water) groups. The animals were anesthetized with ketamin/xylazine (50 and 7 mg/kg, respectively, ip) and systolic blood pressure was then measured from the tail of the animals by a sphygmomanometer. Nitric oxide levels in serum were measured indirectly by evaluation of its stable metabolites (total nitrite and nitrate (NOchi)). After 8 and 12 weeks, systolic blood pressure in the lead acetate group was significantly elevated compared to the control group. Ascorbic acid supplementation could prevent the systolic blood pressure rise in the lead acetate plus ascorbic acid group and there was no significant difference relative to the control group. The serum NOchi levels in lead acetate group significantly decreased in relation to the control group, but this reduction was not significantly different between the lead acetate plus ascorbic acid group and the control group. Results of this study suggest that ascorbic acid as an antioxidant prevents the lead induced hypertension. This effect may be mediated by inhibition of NOchi oxidation and thereby increasing availability of NO.

  9. Effect of ascorbic acid supplementation on nitric oxide metabolites and systolic blood pressure in rats exposed to lead

    Directory of Open Access Journals (Sweden)

    Mohammad Amani

    2010-01-01

    Full Text Available Background: Extended exposure to low levels of lead causes high blood pressure in human and laboratory animals. The mechanism is not completely recognized, but it is relatively implicated with generation of free radicals, oxidant agents such as ROS, and decrease of available nitric oxide (NO. In this study, we have demonstrated the effect of ascorbic acid as an antioxidant on nitric oxide metabolites and systolic blood pressure in rats exposed to low levels of lead. Materials and Methods: The adult male Wistar rats weighing 200-250 g were divided into four groups: control, lead acetate (receiving 100 ppm lead acetate in drinking water, lead acetate plus ascorbic acid (receiving 100 ppm lead acetate and 1 g/l ascorbic acid in drinking water, and ascorbic acid (receiving 1 g/l ascorbic acid in drinking water groups. The animals were anesthetized with ketamin/xylazine (50 and 7 mg/kg, respectively, ip and systolic blood pressure was then measured from the tail of the animals by a sphygmomanometer. Nitric oxide levels in serum were measured indirectly by evaluation of its stable metabolites (total nitrite and nitrate (NOc. Results: After 8 and 12 weeks, systolic blood pressure in the lead acetate group was significantly elevated compared to the control group. Ascorbic acid supplementation could prevent the systolic blood pressure rise in the lead acetate plus ascorbic acid group and there was no significant difference relative to the control group. The serum NOc levels in lead acetate group significantly decreased in relation to the control group, but this reduction was not significantly different between the lead acetate plus ascorbic acid group and the control group. Conclusion: Results of this study suggest that ascorbic acid as an antioxidant prevents the lead induced hypertension. This effect may be mediated by inhibition of NOc oxidation and thereby increasing availability of NO.

  10. Genome-wide meta-analysis of systolic blood pressure in children with sickle cell disease.

    Directory of Open Access Journals (Sweden)

    Pallav Bhatnagar

    Full Text Available In pediatric sickle cell disease (SCD patients, it has been reported that higher systolic blood pressure (SBP is associated with increased risk of a silent cerebral infarction (SCI. SCI is a major cause of neurologic morbidity in children with SCD, and blood pressure is a potential modulator of clinical manifestations of SCD; however, the risk factors underlying these complications are not well characterized. The aim of this study was to identify genetic variants that influence SBP in an African American population in the setting of SCD, and explore the use of SBP as an endo-phenotype for SCI. We conducted a genome-wide meta-analysis for SBP using two SCD cohorts, as well as a candidate screen based on published SBP loci. A total of 1,617 patients were analyzed, and while no SNP reached genome-wide significance (P-value<5.0 x 10(-8, a number of suggestive candidate loci were identified. The most significant SNP, rs7952106 (P-value=8.57 x 10(-7, was in the DRD2 locus on chromosome 11. In a gene-based association analysis, MIR4301 (micro-RNA4301, which resides in an intron of DRD2, was the most significant gene (P-value=5.2 x 10(-5. Examining 27 of the previously reported SBP associated SNPs, 4 SNPs were nominally significant. A genetic risk score was constructed to assess the aggregated genetic effect of the published SBP variants, demonstrating a significant association (P=0.05. In addition, we also assessed whether these variants are associated with SCI, validating the use of SBP as an endo-phenotype for SCI. Three SNPs were nominally associated, and only rs2357790 (5' CACNB2 was significant for both SBP and SCI. None of these SNPs retained significance after Bonferroni correction. Taken together, our results suggest the importance of DRD2 genetic variation in the modulation of SBP, and extend the aggregated importance of previously reported SNPs in the modulation of SBP in an African American cohort, more specifically in children with SCD.

  11. 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

  12. 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...

  13. 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...

  14. Effect of lower on-treatment systolic blood pressure on the risk of atrial fibrillation in hypertensive patients

    DEFF Research Database (Denmark)

    Okin, Peter M; Hille, Darcy A; Larstorp, Anne Cecilie K

    2015-01-01

    UNLABELLED: There is a well-established association between hypertension and atrial fibrillation (AF); indeed, even upper normal systolic blood pressures (SBP) are long-term predictors of incident AF. These findings suggest that more aggressive BP control may reduce the risk of new AF. However, w...... whether targeting hypertensive patients without AF to lower SBP goals can reduce the burden of new AF in this high-risk population. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov. Unique identifier: NCT00338260....

  15. Analysis of Systolic Backflow and Secondary Helical Blood Flow in the Ascending Aorta Using Vector Flow Imaging

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Lindskov; Møller-Sørensen, Hasse; Kjaergaard, Jesper

    2016-01-01

    Secondary rotational flow and systolic backflow are seen in the ascending aorta and, in this study, were analyzed with the vector velocity method transverse oscillation. Twenty-five patients were scanned intra-operatively, and the vector velocities were related to estimates of transesophageal...... that backflow is injurious and that secondary flow is a normal flow phenomenon. The study also shows that transverse oscillation can provide new information on blood flow in the ascending aorta....

  16. An association between systolic blood pressure and stroke among patients with impaired consciousness in out-of-hospital emergency settings

    OpenAIRE

    Irisawa, Taro; Iwami, Taku; Kitamura, Tetsuhisa; Nishiyama, Chika; Sakai, Tomohiko; Tanigawa-Sugihara, Kayo; Hayashida, Sumito; Nishiuchi, Tatsuya; Shiozaki, Tadahiko; Tasaki, Osamu; Kawamura, Takashi; Hiraide, Atsushi; Shimazu, Takeshi

    2013-01-01

    Background: Stroke is difficult to diagnose when consciousness is disturbed. However few reports have discussed the clinical predictors of stroke in out-of-hospital emergency settings. This study aims to evaluate the association between initial systolic blood pressure (SBP) value measured by emergency medical service (EMS) and diagnosis of stroke among impaired consciousness patients. Methods: We included all patients aged 18 years or older who were treated and transported by EMS, and had imp...

  17. Baseline Systolic Blood Pressure Response to Exercise Stress Test Can Predict Exercise Indices following Cardiac Rehabilitation Program

    Directory of Open Access Journals (Sweden)

    Akram Sardari

    2010-11-01

    Full Text Available Background: Systolic blood pressure recovery (rSBP is of prognostic value for predicting the survival and co-morbidity rate in patients with coronary artery disease (CAD. This study investigated the association between rSBP and exercise indices after complete cardiac rehabilitation program (CR in a population-based sample of patients undergoing coronary artery bypass grafting (CABG.Methods: The sample population consisted of 352 patients who underwent pure CABG. The patients underwent standard symptom-limited exercise testing immediately before and also after the completion of the CR sessions. rSBP was defined as the ratio of the systolic blood pressure at 3 minutes in recovery to the systolic blood pressure at peak exercise.Results: An abnormal baseline rSBP after exercise was a strong predictor of exercise parameters in the last session, including metabolic equivalents (β = -0.617, SE = 0.127, p value < 0.001 and peak O2 consumption (β = -1.950, SE = 0.363, p value < 0.001 measured in the last session adjusted for baseline exercise characteristics, demographics, function class, and left ventricular ejection fraction.Conclusion: The current study strongly emphasizes the predictive role of baseline rSBP after exercise in evaluating exercise parameters following CR. This baseline index can predict abnormal METs value, peak O2 consumption, post-exercise heart rate, and heart rate recovery after a 24-session CR program.

  18. Isolated systolic hypertension in an elderly Danish population. Prevalence and daytime ambulatory blood pressure

    DEFF Research Database (Denmark)

    Talleruphuus, Ulrik; Bang, Lia Evi; Wiinberg, Niels;

    2006-01-01

    Isolated systolic hypertension (ISH) is a major risk factor for cardiovascular complications. Nevertheless, data on the prevalence in a representative population do not seem to be available. The prevalence of ISH and the white coat effect was thus studied in a cross-sectional survey of 2806 inhab...

  19. White matter disease in midlife is heritable, related to hypertension, and shares some genetic influence with systolic blood pressure

    Directory of Open Access Journals (Sweden)

    Christine Fennema-Notestine, PhD

    2016-01-01

    Full Text Available White matter disease in the brain increases with age and cardiovascular disease, emerging in midlife, and these associations may be influenced by both genetic and environmental factors. We examined the frequency, distribution, and heritability of abnormal white matter and its association with hypertension in 395 middle-aged male twins (61.9 ± 2.6 years from the Vietnam Era Twin Study of Aging, 67% of whom were hypertensive. A multi-channel segmentation approach estimated abnormal regions within the white matter. Using multivariable regression models, we characterized the frequency distribution of abnormal white matter in midlife and investigated associations with hypertension and Apolipoprotein E-ε4 status and the impact of duration and control of hypertension. Then, using the classical twin design, we estimated abnormal white matter heritability and the extent of shared genetic overlap with blood pressure. Abnormal white matter was predominantly located in periventricular and deep parietal and frontal regions; associated with age (t = 1.9, p = 0.05 and hypertension (t = 2.9, p = 0.004, but not Apolipoprotein ε4 status; and was greater in those with uncontrolled hypertension relative to controlled (t = 3.0, p = 0.003 and normotensive (t = 4.0, p = 0.0001 groups, suggesting that abnormal white matter may reflect currently active cerebrovascular effects. Abnormal white matter was highly heritable (a2 = 0.81 and shared some genetic influences with systolic blood pressure (rA = 0.26, although there was evidence for distinct genetic contributions and unique environmental influences. Future longitudinal research will shed light on factors impacting white matter disease presentation, progression, and potential recovery.

  20. Systolic blood pressure reactions to acute stress are associated with future hypertension status in the Dutch Famine Birth Cohort Study.

    Science.gov (United States)

    Carroll, Douglas; Ginty, Annie T; Painter, Rebecca C; Roseboom, Tessa J; Phillips, Anna C; de Rooij, Susanne R

    2012-08-01

    These analyses examined the association between blood pressure reactions to acute psychological stress and subsequent hypertension status in a substantial Dutch cohort. Blood pressure was recorded during a resting baseline and during three acute stress tasks, Stroop colour word, mirror tracing and speech. Five years later, diagnosed hypertension status was determined by questionnaire. Participants were 453 (237 women) members of the Dutch Famine Birth Cohort. In analysis adjusting for a number of potential confounders, systolic blood pressure reactivity was positively related to future hypertension. This was the case irrespective of whether reactivity was calculated as the peak or the average response to the stress tasks. The association was strongest for reactions to the speech and Stroop tasks. Diastolic blood pressure reactivity was not significantly associated with hypertension. The results provide support for the reactivity hypothesis.

  1. Resistance training alone reduces systolic and diastolic blood pressure in prehypertensive and hypertensive individuals: meta-analysis.

    Science.gov (United States)

    de Sousa, Evitom Corrêa; Abrahin, Odilon; Ferreira, Ana Lorena Lima; Rodrigues, Rejane Pequeno; Alves, Erik Artur Cortinhas; Vieira, Rodolfo Paula

    2017-08-03

    The purpose of this study was to evaluate the effects of resistance training alone on the systolic and diastolic blood pressure in prehypertensive and hypertensive individuals. Our meta-analysis, followed the guidelines of PRISMA. The search for articles was realized by November 2016 using the following electronic databases: BIREME, PubMed, Cochrane Library, LILACS and SciELO and a search strategy that included the combination of titles of medical affairs and terms of free text to the key concepts: 'hypertension' 'hypertensive', 'prehypertensive', 'resistance training', 'strength training', and 'weight-lifting'. These terms were combined with a search strategy to identify randomized controlled trials (RCTs) and identified a total of 1608 articles: 644 articles BIREME, 53 SciELO, 722 PubMed, 122 Cochrane Library and 67 LILACS. Of these, five RCTs met the inclusion criteria and provided data on 201 individuals. The results showed significant reductions for systolic blood pressure (-8.2 mm Hg CI -10.9 to -5.5;I(2): 22.5% P valor for heterogeneity=0.271 and effect size=-0.97) and diastolic blood pressure (-4.1 mm Hg CI -6.3 to -1.9; I(2): 46.5% P valor for heterogeneity=0.113 and effect size=-0.60) when compared to group control. In conclusion, resistance training alone reduces systolic and diastolic blood pressure in prehypertensive and hypertensive subjects. The RCTs studies that investigated the effects of resistance training alone in prehypertensive and hypertensive patients support the recommendation of resistance training as a tool for management of systemic hypertension.Hypertension Research advance online publication, 3 August 2017; doi:10.1038/hr.2017.69.

  2. Comparison of multilevel modeling and the family-based association test for identifying genetic variants associated with systolic and diastolic blood pressure using Genetic Analysis Workshop 18 simulated data.

    Science.gov (United States)

    Wang, Jian; Yu, Robert; Shete, Sanjay

    2014-01-01

    Identifying genetic variants associated with complex diseases is an important task in genetic research. Although association studies based on unrelated individuals (ie, case-control genome-wide association studies) have successfully identified common single-nucleotide polymorphisms for many complex diseases, these studies are not so likely to identify rare genetic variants. In contrast, family-based association studies are particularly useful for identifying rare-variant associations. Recently, there has been some interest in employing multilevel models in family-based genetic association studies. However, the performance of such models in these studies, especially for longitudinal family-based sequence data, has not been fully investigated. Therefore, in this study, we investigated the performance of the multilevel model in the family-based genetic association analysis and compared it with the conventional family-based association test, by examining the powers and type I error rates of the 2 approaches using 3 data sets from the Genetic Analysis Workshop 18 simulated data: genome-wide association single-nucleotide polymorphism data, sequence data, and rare-variants-only data. Compared with the univariate family-based association test, the multilevel model had slightly higher power to identify most of the causal genetic variants using the genome-wide association single-nucleotide polymorphism data and sequence data. However, both approaches had low power to identify most of the causal single-nucleotide polymorphisms, especially those among the relatively rare genetic variants. Therefore, we suggest a unified method that combines both approaches and incorporates collapsing strategy, which may be more powerful than either approach alone for studying genetic associations using family-based data.

  3. Clinical outcomes with a systolic blood pressure lower than 120 mmHg in older patients with high disease burden.

    Science.gov (United States)

    Franco Palacios, Carlos R; Haugen, Eric N; Thompson, Amanda M; Rasmussen, Richard W; Goracke, Nathan; Goyal, Pankaj

    2016-10-01

    The target blood pressure in older patients is controversial. Recent studies provided clinical evidence supporting a target systolic blood pressure 50 years at high risk of cardiovascular events. Retrospective study of 380 consecutive patients ≥60 years with stages 1-5 pre-dialysis chronic kidney disease seen between January 2013 and November 2015. The outcomes of a systolic blood pressure blood pressure blood pressure ≥120 mmHg. Forty-three patients died during the follow up (11.3%). Patients with a systolic blood pressure risk of death: 21 (30.9%) vs 22 (7%). Primary cause of death: Cardiovascular: 11 (25.6%), infectious 9 (20.9%), cancer 5 (11.6%), renal failure 6 (13.9%), COPD/pulmonary fibrosis 2 (4.6%), end stage liver disease 3 (6.9%), traumatic brain injury 1 (2.3%), gastrointestinal hemorrhage 4 (9.3%), complications of diabetes 1 (2.3%), unknown 1 (2.3%). After adjusting for confounding factors, a systolic blood pressure blood pressure. A systolic blood pressure below 120 mmHg in older patients with high disease burden was associated with adverse outcomes. Individualization of blood pressure therapy to each specific patient is warranted.

  4. Left ventricular hypertrophy in relation to systolic blood pressure and the angiotensin converting enzyme I/D polymorphism in Chinese

    Institute of Scientific and Technical Information of China (English)

    Alexander P. Headley; Yan Li; Yi Zhang; Ji-Yong Ge; Qi-Fang Huang; Ji-Guang Wang

    2009-01-01

    Objective There is little population-based data on the prevalence and the environmental or genetic determinants of left ventricular hypertrophy (LVH) in China. The purpose of this paper is to study LVH in relation to systolic blood pressure and the angiotensin converting enzyme (ACE) insertion/deletion(I/D) polymorphism in Chinese. Methods We recorded 12-lead ECG (CardioSoft, v4.2) in 1365 residents in the Jingning County, Zhejiang Province, China. LVH was defined according to the gender-specific Sokolow-Lyon and Comell product ECG criteria. Results Regardless of whether the Sokolow-Lyon or Comell product ECG criteria was used, the prevalence of LVH (20.7% and 4.8%, respectively) significantly (P<0.0001) increased with male gender (odds ratio [OR] 2.33 and 7.15) and systolic blood pressure (per 10 mm Hg increase, OR 1.46 and 1.33). If the Sokolow-Lyon criteria was used, the prevalence of LVH was also influenced by alcohol intake (OR 1.44, P=0.03) and body mass index (OR 0.83, P=0.0005). The association between the Sokolow-Lyon voltage amplitude and the ACE I/D polymorphism was dependent on antihypertensive therapy (P=0.01). In 1262 untreated subjects, but not 103 patients on antihypertensive medication, the ACE DD compared with Ⅱ subjects had significantly higher Sokolow-Lyon voltage amplitudes (29.8±0.6 vs. 28.0±20.5 mV, P=0.02) and higher risk of LVH (OR 1.74, 95% CI: 1. 12-2.69, P=0.01). Conclusion LVH is prevalent in Chinese, and is associated with systolic blood pressure and the ACE D allele. The genetic association might be modulated by antihypertensive therapy.

  5. Randomised double-blind comparison of placebo and active drugs for effects on risks associated with blood pressure variability in the Systolic Hypertension in Europe trial.

    Directory of Open Access Journals (Sweden)

    Azusa Hara

    Full Text Available BACKGROUND: In the Systolic Hypertension in Europe trial (NCT02088450, we investigated whether systolic blood pressure variability determines prognosis over and beyond level. METHODS: Using a computerised random function and a double-blind design, we randomly allocated 4695 patients (≥60 years with isolated systolic hypertension (160-219/<95 mm Hg to active treatment or matching placebo. Active treatment consisted of nitrendipine (10-40 mg/day with possible addition of enalapril (5-20 mg/day and/or hydrochlorothiazide (12.5-25.0 mg/day. We assessed whether on-treatment systolic blood pressure level (SBP, visit-to-visit variability independent of the mean (VIM or within-visit variability (WVV predicted total (n = 286 or cardiovascular (n = 150 mortality or cardiovascular (n = 347, cerebrovascular (n = 133 or cardiac (n = 217 endpoints. FINDINGS: At 2 years, mean between-group differences were 10.5 mm Hg (p<0.0001 for SBP, 0.29 units (p = 0.20 for VIM, and 0.07 mm Hg (p = 0.47 for WVV. Active treatment reduced (p≤0.048 cardiovascular (-28%, cerebrovascular (-40% and cardiac (-24% endpoints. In analyses dichotomised by the median, patients with low vs. high VIM had similar event rates (p≥0.14. Low vs. high WVV was not associated with event rates (p≥0.095, except for total and cardiovascular mortality on active treatment, which were higher with low WVV (p≤0.0003. In multivariable-adjusted Cox models, SBP predicted all endpoints (p≤0.0043, whereas VIM did not predict any (p≥0.058. Except for an inverse association with total mortality (p = 0.042, WVV was not predictive (p≥0.15. Sensitivity analyses, from which we excluded blood pressure readings within 6 months after randomisation, 6 months prior to an event or both were confirmatory. CONCLUSIONS: The double-blind placebo-controlled Syst-Eur trial demonstrated that blood-pressure lowering treatment reduces cardiovascular complications by decreasing

  6. Association Between Short-Term Systolic Blood Pressure Variability and Carotid Intima-Media Thickness in ELSA-Brasil Baseline.

    Science.gov (United States)

    Ribeiro, Adèle H; Lotufo, Paulo A; Fujita, André; Goulart, Alessandra C; Chor, Dora; Mill, José G; Bensenor, Isabela M; Santos, Itamar S

    2017-05-05

    Blood pressure (BP) is associated with carotid intima-media thickness (CIMT), but few studies have explored the association between BP variability and CIMT. We aimed to investigate this association in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline. We analyzed data from 7,215 participants (56.0% women) without overt cardiovascular disease (CVD) or antihypertensive use. We included 10 BP readings in varying positions during a 6-hour visit. We defined BP variability as the SD of these readings. We performed a 2-step analysis. We first linearly regressed the CIMT values on main and all-order interaction effects of the variables age, sex, body mass index, race, diabetes diagnosis, dyslipidemia diagnosis, family history of premature CVD, smoking status, and ELSA-Brasil site, and calculated the residuals (residual CIMT). We used partial least square path analysis to investigate whether residual CIMT was associated with BP central tendency and BP variability. Systolic BP (SBP) variability was significantly associated with residual CIMT in models including the entire sample (path coefficient [PC]: 0.046; P < 0.001), and in women (PC: 0.046; P = 0.007) but not in men (PC: 0.037; P = 0.09). This loss of significance was probably due to the smaller subsample size, as PCs were not significantly different according to sex. We found a small but significant association between SBP variability and CIMT values. This was additive to the association between SBP central tendency and CIMT values, supporting a role for high short-term SBP variability in atherosclerosis.

  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.

    2016-04-01

    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.

  8. Antihypertensive medications and sexual function in women: Baseline data from the Systolic Blood Pressure Intervention Trial (SPRINT)

    Science.gov (United States)

    Thomas, Holly N.; Evans, Gregory W.; Berlowtiz, Dan R.; Chertow, Glenn M.; Conroy, Molly B.; Foy, Capri G.; Glasser, Stephen P.; Lewis, Cora E.; Riley, William T.; Russell, Laurie; Williams, Olubunmi; Hess, Rachel

    2016-01-01

    Objectives Hypertension is a risk factor for the development of cardiovascular and kidney disease, but treatment can substantially reduce risks. Many patients avoid antihypertensive medications due to fear of side effects. While associations between antihypertensives and sexual dysfunction in men have been documented, it remains unclear whether antihypertensives are associated with sexual dysfunction in women. We conducted a cross-sectional analysis of baseline data from women in the Systolic Blood Pressure Intervention Trial (SPRINT) to evaluate the relations among class of antihypertensive medication and the outcomes (a) sexual activity and (b) sexual function. Methods SPRINT enrolled individuals 50 and older with hypertension at high risk for cardiovascular disease. A subset of participants completed questionnaires regarding quality of life (QoL), including sexual function. Antihypertensive class was determined by medications taken at baseline. Results Of 690 women in the QoL subset of SPRINT, 183 (26.5%) were sexually active. There were no significant differences in sexual activity among women taking one or more antihypertensives and women not taking any. Women taking an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker (ACEI/ARB) had higher odds of sexual activity [OR 1.66 (1.12-4.27), p=0.011]. Among sexually active women, the prevalence of sexual dysfunction was high (52.5%). No class of medication was associated with sexual dysfunction in the multivariable model. Conclusions ACEI/ARB use was associated with higher odds of sexual activity. While prevalence of sexual dysfunction was high, no single class of antihypertensive medication was associated with sexual dysfunction. PMID:27032074

  9. 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.

  10. Azilsartan medoxomil plus chlorthalidone reduces blood pressure more effectively than olmesartan plus hydrochlorothiazide in stage 2 systolic hypertension.

    Science.gov (United States)

    Cushman, William C; Bakris, George L; White, William B; Weber, Michael A; Sica, Domenic; Roberts, Andrew; Lloyd, Eric; Kupfer, Stuart

    2012-08-01

    Azilsartan medoxomil, an effective, long-acting angiotensin II receptor blocker, is a new treatment for hypertension that is also being developed in fixed-dose combinations with chlorthalidone, a potent, long-acting thiazide-like diuretic. We compared once-daily fixed-dose combinations of azilsartan medoxomil/chlorthalidone force titrated to a high dose of either 40/25 mg or 80/25 mg with a fixed-dose combination of the angiotensin II receptor blocker olmesartan medoxomil plus the thiazide diuretic hydrochlorothiazide force titrated to 40/25 mg. The design was a randomized, 3-arm, double-blind, 12-week study of 1071 participants with baseline clinic systolic blood pressure 160 to 190 mm Hg and diastolic blood pressure ≤119 mm Hg. Patients had a mean age of 57 years; 59% were men, 73% were white, and 22% were black. At baseline, mean clinic blood pressure was 165/96 mm Hg and 24-hour mean blood pressure was 150/88 mm Hg. Changes in clinic (primary end point) and ambulatory systolic blood pressures at week 12 were significantly greater in both azilsartan medoxomil/chlorthalidone arms than in the olmesartan/hydrochlorothiazide arm (Pblood pressure (mean±SE) were -42.5±0.8, -44.0±0.8, and -37.1±0.8 mm Hg, respectively. Changes in 24-hour ambulatory systolic blood pressure were -33.9±0.8, -36.3±0.8, and -27.5±0.8 mm Hg, respectively. Adverse events leading to permanent drug discontinuation occurred in 7.9%, 14.5%, and 7.1% of the groups given azilsartan medoxomil/chlorthalidone 40/25 mg, azilsartan medoxomil/chlorthalidone 80/25 mg, and olmesartan/hydrochlorothiazide 40/25 mg, respectively. This large, forced-titration study has demonstrated superior antihypertensive efficacy of azilsartan medoxomil/chlorthalidone fixed-dose combinations compared with the maximum approved dose of olmesartan/hydrochlorothiazide.

  11. Nesfatin-1 and Vitamin D levels may be associated with systolic and diastolic blood pressure values and hearth rate in polycystic ovary syndrome

    Directory of Open Access Journals (Sweden)

    Figen Kir Sahin

    2015-07-01

    Full Text Available Obesity, insulin resistance (IR, inflammation, and hyperandrogenism may lead to polycystic ovary syndrome (PCOS and hypertension. Nesfatin-1 (N1 may be related to IR, obesity, and hypertension. Furthermore, a vitamin D (VD deficiency is associated with hypertension and PCOS. We aimed to investigate N1 and VD levels in PCOS that have an effect on systolic and diastolic blood pressure (BP and heart rate (HR.This study included 54 patients with PCOS and 48 age-body mass index (BMI-matched healthy controls. PCOS was diagnosed according to clinical practice guidelines. Ferriman-Gallwey scores (FGS were calculated, while N1, VD, and other hormonal and biochemical parameters were measured for all subjects. Systolic and diastolic BP was measured as well. HR was calculated using an electrocardiogram.The levels of N1 (p < 0.001, high-sensitivity C-reactive protein (hs-CRP (p = 0.036, homeostasis model assessment as an index of insulin resistance (HOMA-IR (p < 0.001, systolic (p < 0.001 and diastolic (p < 0.001 BP and HR (p < 0.001 in the PCOS group were significantly higher than in the control group. However, the VD levels of the PCOS group were lower than the control group (p = 0.004. N1 had a strong positive correlation with BMI, HOMA-IR, hs-CRP, luteinizing hormone, systolic and diastolic BP, and HR. VD levels were negatively correlated with HOMA-IR and luteinizing hormone.Elevated N1 and decreased VD levels may be related to the presence of high-normal BP or hypertension in PCOS subjects.  N1 level may be associated with an increased BP due to its relation to inflammation and IR.

  12. Nesfatin-1 and Vitamin D levels may be associated with systolic and diastolic blood pressure values and hearth rate in polycystic ovary syndrome.

    Science.gov (United States)

    Sahin, Figen Kir; Sahin, Serap Baydur; Ural, Ulku Mete; Cure, Medine Cumhur; Senturk, Senol; Tekin, Yesim Bayoglu; Balik, Gulsah; Cure, Erkan; Yuce, Suleyman; Kirbas, Aynur

    2015-07-09

    Obesity, insulin resistance (IR), inflammation, and hyperandrogenism may lead to polycystic ovary syndrome (PCOS) and hypertension. Nesfatin-1 (N1) may be related to IR, obesity, and hypertension. Furthermore, a vitamin D (VD) deficiency is associated with hypertension and PCOS. We aimed to investigate N1 and VD levels in PCOS that have an effect on systolic and diastolic blood pressure (BP) and heart rate (HR).This study included 54 patients with PCOS and 48 age-body mass index (BMI)-matched healthy controls. PCOS was diagnosed according to clinical practice guidelines. Ferriman-Gallwey scores (FGS) were calculated, while N1, VD, and other hormonal and biochemical parameters were measured for all subjects. Systolic and diastolic BP was measured as well. HR was calculated using an electrocardiogram.The levels of N1 (p < 0.001), high-sensitivity C-reactive protein (hs-CRP) (p = 0.036), homeostasis model assessment as an index of insulin resistance (HOMA-IR) (p < 0.001), systolic (p < 0.001) and diastolic (p < 0.001) BP and HR (p < 0.001) in the PCOS group were significantly higher than in the control group. However, the VD levels of the PCOS group were lower than the control group (p = 0.004). N1 had a strong positive correlation with BMI, HOMA-IR, hs-CRP, luteinizing hormone, systolic and diastolic BP, and HR. VD levels were negatively correlated with HOMA-IR and luteinizing hormone.Elevated N1 and decreased VD levels may be related to the presence of high-normal BP or hypertension in PCOS subjects.  N1 level may be associated with an increased BP due to its relation to inflammation and IR.

  13. Peritoneal dialysis impairs nitric oxide homeostasis and may predispose infants with low systolic blood pressure to cerebral ischemia.

    Science.gov (United States)

    Carlström, Mattias; Cananau, Carmen; Checa, Antonio; Wide, Katarina; Sartz, Lisa; Svensson, Anders; Wheelock, Craig E; Westphal, Susanne; Békássy, Zivile; Bárány, Peter; Lundberg, Jon O; Hansson, Sverker; Weitzberg, Eddie; Krmar, Rafael T

    2016-08-31

    Infants on chronic peritoneal dialysis (PD) have an increased risk of developing neurological morbidities; however, the underlying biological mechanisms are poorly understood. In this clinical study, we investigated whether PD-mediated impairment of nitric oxide (NO) bioavailability and signaling, in patients with persistently low systolic blood pressure (SBP), can explain the occurrence of cerebral ischemia. Repeated blood pressure measurements, serial neuroimaging studies, and investigations of systemic nitrate and nitrite levels, as well as NO signaling, were performed in ten pediatric patients on PD. We consistently observed the loss of both inorganic nitrate (-17 ± 3%, P low SBP developed ischemic cerebral complications. Our data suggests that PD impairs NO homeostasis and predisposes infants with persistently low SBP to cerebral ischemia. These findings improve current understanding of the pathogenesis of infantile cerebral ischemia induced by PD and may lead to the new treatment strategies to reduce neurological morbidities. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Effects of Parental Smoking on Exercise Systolic Blood Pressure in Adolescents

    OpenAIRE

    Hacke, Claudia; Weisser, Burkhard

    2015-01-01

    Background In adults, exercise blood pressure seems to be more closely related to cardiovascular risk than resting blood pressure; however, few data are available on the effects of familial risk factors, including smoking habits, on exercise blood pressure in adolescents. Methods and Results Blood pressure at rest and during exercise, parental smoking, and other familial risk factors were investigated in 532 adolescents aged 12 to 17 years (14.6±1.5 years) in the Kiel EX.PRESS. (EXercise PRES...

  15. Effects of Parental Smoking on Exercise Systolic Blood Pressure in Adolescents

    OpenAIRE

    Hacke, Claudia; Weisser, Burkhard

    2015-01-01

    Background In adults, exercise blood pressure seems to be more closely related to cardiovascular risk than resting blood pressure; however, few data are available on the effects of familial risk factors, including smoking habits, on exercise blood pressure in adolescents. Methods and Results Blood pressure at rest and during exercise, parental smoking, and other familial risk factors were investigated in 532 adolescents aged 12 to 17 years (14.6±1.5 years) in the Kiel EX.PRESS. (EXercise PRES...

  16. Long-term impact of systolic blood pressure and glycemia on the development of microalbuminuria in essential hypertension.

    Science.gov (United States)

    Pascual, Jose Maria; Rodilla, Enrique; Gonzalez, Carmen; Pérez-Hoyos, Santiago; Redon, Josep

    2005-06-01

    The objective was to assess the temporal impact of factors related to the development of microalbuminuria during the follow-up of young adult normoalbuminurics with high-normal blood pressure or at stage 1 of essential hypertension. Prospective follow-up was conducted on 245 normoalbuminuric hypertensive subjects (mean age 40.9 years; 134 men; blood pressure 139.7/88.6 mm Hg; body mass index 28.5 kg/m2) never treated previously with antihypertensive drugs, with yearly urinary albumin excretion measurements, until the development of microalbuminuria. After enrollment, patients were placed on usual care including nonpharmacological treatment or with an antihypertensive drug regime to achieve a blood pressure of 15 mg per 24-hour systolic blood pressure >139 mm Hg and a positive trend in fasting glucose were observed in the univariate analyses. However, in the multivariate analysis, only the baseline urinary albumin excretion and the trend of fasting glucose were independently related to the risk of developing microalbuminuria. In mild hypertensives, the development of microalbuminuria was linked to insufficient blood pressure control and to a progressive increment of glucose values.

  17. EVALUATION OF THE EFFECT OF “WAKOUBA '' ON THE LIPID PROFILE, SYSTOLIC BLOOD PRESSURE (SBP DIASTOLIC (DBP AND BLOOD GLUCOSE IN HYPERTENSIVE RABBITS

    Directory of Open Access Journals (Sweden)

    Tiekpa Wawa J

    2014-11-01

    Full Text Available This study aims at evaluating the effects of Wakouba, an extract of the fronds of oil palm tree Elaeis guineensis (Jacq traditionally used in the treatment of high blood pressure, on lipid profile, urea, creatinine, blood glucose, systolic blood pressure (SBP, diastolic (DBP and heart rate (HR in hypertensive rabbits. Methods: Twenty four rabbits (24 divided into six (06 groups of four rabbits each weighing between 1.5 ±3.0 to 2± 1.5 kg were used. Group 1 served as witness, group 2 sick and untreated control, groups 3, 4, 5, and 6 were used as experimental groups (sick+treatment. Throughout the experiment the witness group received distilled water; adrenaline was administered to the sick control group. After 10 days of adrenaline injection, hypertension has been stabilized in sick groups (group 2 to 6 and blood was taken for the determination of urea, creatinine, and lipids. Four (04 of the five (05 groups of hypertensive rabbits were treated with two (2 doses of " Wakouba " 950 and 2500 mg / kg bw and two ( 02 doses of ténordate 10 and 20 mg / kg BW, two(2 group by two(2 group . After ten (10 days of treatment, the SBP and DBP and HR were measured, blood was collected for determination of the same biochemical parameters. Results: The study of the effect of Wakouba and ternodate on the changes in systolic blood pressure SBP, DBP and heart rate (HR showed a significant decrease (P up to normalization of these parameters after 10 days of treatment. Similarly, the measurement of serum lipid profile in hypertensive rabbits treated with Wakouba (950mg / kg bw and tenordate (20 mg / kg bw showed a significant reduction in (P values of total cholesterol, LDL cholesterol and triglycerides in contrast to HDL cholesterol which has increased significantly compared to the control group. Same doses also normalize serum glucose, urea and creatinine. Histological sections performed on the kidney and the heart of hypertensive rabbit showed congestion of

  18. Impaired systolic blood pressure recovery and heart rate recovery after graded exercise in patients with metabolic syndrome.

    Science.gov (United States)

    Alihanoglu, Yusuf I; Yildiz, Bekir S; Kilic, I Dogu; Uludag, Burcu; Demirci, Emre E; Zungur, Mustafa; Evrengul, Harun; Kaftan, Asuman H

    2015-01-01

    The aim of this study was to evaluate and compare systolic blood pressure recovery and heart rate recovery (HRR) values obtained at various time intervals after maximal graded exercise treadmill testing between patients with metabolic syndrome (MS) and the controls without MS. To our knowledge, this is the first study indicating systolic blood pressure recovery (SBPR) impairment and its relations to HRR and other variables in this group of patients. The study population included 110 patients with MS (67 men, 43 women; mean age: 46 ± 9 years) and 110 control subjects who did not meet the criteria for MS (58 men, 52 women; mean age: 44 ± 10 years). All patients were selected from nonobese, apparently healthy sedentary individuals who had the ability to perform maximum exercise testing. SBPR was assessed by calculating the ratio of systolic blood pressure (SBP) obtained in the third minute of the recovery period to either the peak-exercise SBP or the SBP in the first minute of the recovery period after graded exercise testing. HRR values were calculated by subtracting the HR at the first, second, third, fourth, and fifth minutes of the recovery period from the HR reached at peak exercise. There was no significant difference found between the 2 groups with respect to age and sex distribution. As expected, patients with MS had higher waist circumference, fasting plasma glucose and serum triglyceride, and lower high-density lipoprotein cholesterol compared with control subjects. All HRR values calculated in the first, second, third, fourth, and fifth minutes were significantly detected lower in the MS group compared with the control group (HRR 1st: 32 ± 10 vs 36 ± 11; P = 0.009; HRR 2nd: 47 ± 10 vs 51 ± 11; P = 0.02; HRR 3rd: 53 ± 11 vs 58 ± 12; P = 0.001; HRR 4th: 57 ± 11 vs 64 ± 12; P 1 in patients with MS (1.01 ± 0.2 vs 0.91 ± 0.1 and 1.01 ± 0.1 vs 0.94 ± 0.1) and these were statistically significant compared with the control group (P exercise

  19. High-sensitivity troponin T and cardiovascular events in systolic blood pressure categories: atherosclerosis risk in communities study.

    Science.gov (United States)

    Pokharel, Yashashwi; Sun, Wensheng; de Lemos, James A; Taffet, George E; Virani, Salim S; Ndumele, Chiadi E; Mosley, Thomas H; Hoogeveen, Ron C; Coresh, Josef; Wright, Jacqueline D; Heiss, Gerardo; Boerwinkle, Eric A; Bozkurt, Biykem; Solomon, Scott D; Ballantyne, Christie M; Nambi, Vijay

    2015-01-01

    Based on observational studies, there is a linear increase in cardiovascular risk with higher systolic blood pressure (SBP), yet clinical trials have not shown benefit across all SBP categories. We assessed whether troponin T measured using high-sensitivity assay was associated with cardiovascular disease within SBP categories in 11 191 Atherosclerosis Risk in Communities study participants. Rested sitting SBP by 10-mm Hg increments and troponin categories were identified. Incident heart failure hospitalization, coronary heart disease, and stroke were ascertained for a median of 12 years after excluding individuals with corresponding disease. Approximately 53% of each type of cardiovascular event occurred in individuals with SBPrisk compared with those with troponin T risk, particularly for heart failure. Individuals with lower SBP but measurable troponin T had greater cardiovascular risk compared with those with suboptimal SBP but undetectable troponin T. Future trials of systolic hypertension may benefit by using high-sensitivity troponin T to target high-risk patients. © 2014 American Heart Association, Inc.

  20. Associations of gestational age and intrauterine growth with systolic blood pressure in a family-based study of 386,485 men in 331,089 families.

    Science.gov (United States)

    Lawlor, Debbie A; Hübinette, Anna; Tynelius, Per; Leon, David A; Smith, George Davey; Rasmussen, Finn

    2007-02-06

    We conducted a family-based study to explore mechanisms underlying the associations of birth weight and gestational age with systolic blood pressure measured at 17 to 19 years of age. A record linkage study of 386,485 singleton-born men from 331,089 families was undertaken. Birth weight was inversely associated with systolic blood pressure within siblings, with a mean difference (adjusted for age at examination, examination center, and year of examination) within siblings per 1-SD difference in birth weight of -0.21 mm Hg (95% CI, -0.33 to -0.08) and between nonsiblings of -0.12 (95% CI, -0.16 to -0.08). Gestational age was inversely associated with systolic blood pressure within siblings (-0.18 mm Hg; 95% CI, -0.25 to -0.11, per week of gestational age) and between nonsiblings (-0.26 mm Hg; 95% CI, -0.29 to -0.24). Adjustment for socioeconomic position and maternal characteristics did not alter these within- or between-family associations. Furthermore, the associations were not affected by adjustment for paternal height, body mass index, or systolic blood pressure. Our present findings suggest that the inverse associations of birth weight and gestational age with systolic blood pressure are not explained by confounding resulting from family socioeconomic position or other factors that are shared by siblings. Variations in maternal metabolic or vascular health during pregnancy or placental implantation and function may explain these associations.

  1. Increased systolic ambulatory blood pressure and microalbuminuria in treated and non-treated hypertensive smokers

    DEFF Research Database (Denmark)

    Sørensen, Kaspar; Kristensen, Kjeld S; Bang, Lia E

    2004-01-01

    The primary aim of the present study was to evaluate the impact of smoking status on both clinic and ambulatory blood pressure (BP) and heart rate (HR) by using 24-h ambulatory BP monitoring in treated and non-treated hypertensive smokers and non-smokers. A secondary aim was to evaluate the inter......The primary aim of the present study was to evaluate the impact of smoking status on both clinic and ambulatory blood pressure (BP) and heart rate (HR) by using 24-h ambulatory BP monitoring in treated and non-treated hypertensive smokers and non-smokers. A secondary aim was to evaluate...

  2. Effects of parental smoking on exercise systolic blood pressure in adolescents

    National Research Council Canada - National Science Library

    Hacke, Claudia; Weisser, Burkhard

    2015-01-01

    .... Blood pressure at rest and during exercise, parental smoking, and other familial risk factors were investigated in 532 adolescents aged 12 to 17 years (14.6±1.5 years) in the Kiel EX.PRESS. (EXercise PRESSure) Study...

  3. Differentiation of Overweight from Normal Weight Young Adults by Postprandial Heart Rate Variability and Systolic Blood Pressure

    Science.gov (United States)

    Taffe, Lauren; Stancil, Kimani; Bond, Vernon; Pemminati, Sudhakar; Gorantla, Vasavi Rakesh; Kadur, Kishan

    2016-01-01

    Introduction Obesity and cardiovascular disease are inextricably linked and the health community’s response to the current epidemic of adolescent obesity may be improved by the ability to target adolescents at highest risk for developing cardiovascular disease in the future. Overweight manifests early as autonomic dysregulation and current methods do not permit differentiation of overweight adolescents or young adults at highest risk for developing cardiovascular disease. Aim This study was designed to test the hypothesis that scaling exponents motivated by nonlinear fractal analyses of Heart Rate Variability (HRV) differentiate overweight, otherwise healthy adolescent/young adult subjects at risk for developing prehypertension, the primary forerunner of cardiovascular disease. Materials and Methods The subjects were 18-20year old males with Body Mass Index (BMI) 20.1-42.5kg/m2. Electrocardiographic inter-beat (RR) intervals were measured during 3h periods of bed rest after overnight fasting and ingestion of 900Cal high-carbohydrate and high-fat test beverages on separate days. Detrended Fluctuation Analysis (DFA), k-means cluster and ANOVA analyses of scaling coefficients α, α1, and α2, showed dependencies on hourly measurements of systolic blood pressure and on premeasured BMI. Results It was observed that α value increased during the caloric challenge, appears to represent metabolically-induced changes in HRV across the participants. An ancillary analysis was performed to determine the dependency on BMI without BMI as a parameter. Cluster analysis of the high-carbohydrate test beverage treatment and the high-fat treatment produced grouping with very little overlap. ANOVA on both clusters demonstrated significance at p<0.001. We were able to demonstrate increased sympathetic modulation of our study group during ingestion and metabolism of isocaloric high-carbohydrate and high-fat test beverages. Conclusion These findings demonstrate significantly different

  4. Isolated systolic hypertension in an elderly Danish population. Prevalence and daytime ambulatory blood pressure

    DEFF Research Database (Denmark)

    Talleruphuus, Ulrik; Bang, Lia Evi; Wiinberg, Niels;

    2006-01-01

    inhabitants aged 70-80 years. In untreated subjects, the prevalence of ISH was 17.4% (95% CI 14.9-20.2) in women and 13.5% (95% CI 11.3-15.9) in men using clinic blood pressure at first visit. The prevalence increased significantly with age. The prevalence was reduced to 10.4% when using the average of all...

  5. Increased Systolic and Diastolic Blood Pressure Is Associated With Altered Gut Microbiota Composition and Butyrate Production in Early Pregnancy.

    Science.gov (United States)

    Gomez-Arango, Luisa F; Barrett, Helen L; McIntyre, H David; Callaway, Leonie K; Morrison, Mark; Dekker Nitert, Marloes

    2016-10-01

    The risk of developing pregnancy-induced hypertension and preeclampsia is higher in obese pregnant women. In obesity, the composition of the gut microbiota is altered. Obesity is also associated with low-grade inflammation. Metabolites from the gut microbiota may contribute to both hypertension and inflammation. The aim of this study is to investigate whether the composition of the gut microbiota in overweight and obese pregnant women is associated with blood pressure and levels of plasminogen activator inhibitor-1. The composition of the gut microbiota was determined with 16S ribosomal RNA sequencing in 205 women at 16 weeks gestation from the SPRING study (the Study of Probiotics in Gestational Diabetes). Expression of butyrate-producing genes in the gut microbiota was assessed by real-time polymerase chain reaction. Plasminogen activator inhibitor-1 levels were measured in fasting serum of a subset of 70 women. Blood pressure was slightly but significantly higher in obese compared with overweight women. The abundance of the butyrate-producing genus Odoribacter was inversely correlated with systolic blood pressure. Butyrate production capacity was decreased, but plasminogen activator inhibitor-1 concentrations increased in obese pregnant women. Plasminogen activator inhibitor-1 levels were inversely correlated with expression of butyrate kinase and Odoribacter abundance. This study shows that in overweight and obese pregnant women at 16 weeks gestation, the abundance of butyrate-producing bacteria and butyrate production in the gut microbiota is significantly negatively associated with blood pressure and with plasminogen activator inhibitor-1 levels. Increasing butyrate-producing capacity may contribute to maintenance of normal blood pressure in obese pregnant women.

  6. Systolic Blood Pressure Control Among Individuals With Type 2 Diabetes: A Comparative Effectiveness Analysis of Three Interventions.

    Science.gov (United States)

    Espeland, Mark A; Probstfield, Jeffery; Hire, Donald; Redmon, J Bruce; Evans, Gregory W; Coday, Mace; Lewis, Cora E; Johnson, Karen C; Wilmoth, Sharon; Bahnson, Judy; Dulin, Michael F; Green, Jennifer B; Knowler, William C; Kitabchi, Abbas; Murillo, Anne L; Osei, Kwame; Rehman, Shakaib U; Cushman, William C

    2015-08-01

    The relative effectiveness of 3 approaches to blood pressure control-(i) an intensive lifestyle intervention (ILI) focused on weight loss, (ii) frequent goal-based monitoring of blood pressure with pharmacological management, and (iii) education and support-has not been established among overweight and obese adults with type 2 diabetes who are appropriate for each intervention. Participants from the Action for Health in Diabetes (Look AHEAD) and the Action to Control Cardiovascular Risk in Diabetes (ACCORD) cohorts who met criteria for both clinical trials were identified. The proportions of these individuals with systolic blood pressure (SBP) Look AHEAD and 1,129 ACCORD participants with baseline SBPs between 130 and 159 mm Hg, ILI (OR = 1.46; 95% CI = [1.18-1.81]) and frequent goal-based monitoring with pharmacotherapy (OR = 1.51; 95% CI = [1.16-1.97]) yielded higher rates of blood pressure control compared to education and support. The intensive behavioral-based intervention may have been more effective among individuals with body mass index >30 kg/m2, while frequent goal-based monitoring with medication management may be more effective among individuals with lower body mass index (interaction P = 0.047). Among overweight and obese adults with type 2 diabetes, both ILI and frequent goal-based monitoring with pharmacological management can be successful strategies for blood pressure control. clinicaltrials.gov identifiers NCT00017953 (Look AHEAD) and NCT00000620 (ACCORD). © American Journal of Hypertension, Ltd 2015. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Lower Protein-to-Carbohydrate Ratio in Maternal Diet is Associated with Higher Childhood Systolic Blood Pressure up to Age Four Years

    Directory of Open Access Journals (Sweden)

    Michelle L. Blumfield

    2015-04-01

    Full Text Available The prenatal environment can influence development of offspring blood pressure (BP, which tracks into adulthood. This prospective longitudinal study investigated whether maternal pregnancy dietary intake is associated with the development of child BP up to age four years. Data are from 129 mother-child dyads enrolled in the Women and Their Children’s Health study. Maternal diet was assessed using a validated 74-item food frequency questionnaire at 18 to 24 weeks and 36 to 40 weeks, with a reference period of the previous three months. Child systolic and diastolic BP were measured at 3, 6, 9, 12, 24, 36 and 48 months, using an automated BP monitor. Using mixed-model regression analyses adjusted for childhood growth indices, pregnancy intakes of percentage of energy (E% polyunsaturated fat (β coefficient 0.73; 95% CI 0.003, 1.45; p = 0.045, E% omega-6 fatty acids (β coefficient 0.89; 95% CI 0.09, 1.69; p = 0.03 and protein-to-carbohydrate (P:C ratio (β coefficient −14.14; 95% CI −27.68, −0.60; p = 0.04 were associated with child systolic BP trajectory up to 4 years. Child systolic BP was greatest at low proportions of dietary protein (<16% of energy and high carbohydrate (>40% of energy intakes. There may be an ideal maternal macronutrient ratio associated with optimal infant BP. Maternal diet, which is potentially modifiable, may play an important role in influencing offspring risk of future hypertension.

  8. Gender difference and economic gradients in the secular trend of population systolic blood pressure

    DEFF Research Database (Denmark)

    Andersen, Ulla; Jensen, Gorm B

    2013-01-01

    To a large extent population blood pressure (PBP) affects morbidity and mortality in the society. Reports indicated that PBP decreased in many western countries. The associations between the main cardiovascular risk factors and the changing PBP have been described. The aim of this study....... In addition, there was a trend towards a lowering of risk-factor adjusted SBP in the high income women with time. The mechanism that lies behind the associations between trend in SBP and income is not known but data suggest that poor lifestyle may explain some of the differences. The treated hypertensives...... was to investigate association between income factors and trends in population BP and hypertension. Copenhagen City Heart Study is a prospective longitudinal epidemiological study on almost 20000 individuals through four surveys from 1976 to 2003. The BP measurement was fully standardised. Questionnaires...

  9. Evaluation of prehospital and emergency department systolic blood pressure as a predictor of in-hospital mortality.

    Science.gov (United States)

    Lalezarzadeh, Fariborz; Wisniewski, Paul; Huynh, Katie; Loza, Maria; Gnanadev, Dev

    2009-10-01

    Hypotension is a trauma activation criterion validated by multiple studies. However, field systolic blood pressures (SBP) are still met with skepticism. How significant is the role of prehospital (PH) and emergency department (ED) SBP in the patient's overall condition? A review of the trauma registry over a 5-year period was conducted. PH SBPs were stratified into four categories: severe (SBP 80 mmHg or less), moderate (81-100 mmHg), mild hypotension (101-120 mmHg), and normotension (greater than 120 mmHg). These four groups were further subcategorized into the patients who were hypotensive, SBP 90 mmHg or less in the ED, versus those that were not (SBP greater than 90 mmHg). Data for 6964 patients were analyzed. Patients with PH SBP of 80 mmHg or less compared with patients who had PH SBP of greater than 80 mmHg had higher mortality (OR, 9; 95% CI, 6.45-12.84). Patients with both PH SBP 80 mmHg or less and ED SBP 90 mmHg or less had the highest risk of mortality (50%) and highest need for emergent operative intervention (54%). PH and ED hypotension is a strong predictor of in-hospital mortality and need for emergent surgical intervention in trauma patients. Field or ED blood pressures should serve as a significant marker of the patient's condition.

  10. Clinical effect of naturally random allocation to lower systolic blood pressure beginning before the development of hypertension.

    Science.gov (United States)

    Ference, Brian A; Julius, Stevo; Mahajan, Nitin; Levy, Phillip D; Williams, Kim Allan; Flack, John M

    2014-06-01

    Systolic blood pressure (SBP) rises approximately linearly with age in most societies. The cause of this rise is unclear. We tested the hypothesis that SBP is causally associated with the rate of rise in SBP with age by evaluating the effect of 12 polymorphisms associated with lower SBP on the age-related rate of rise in SBP in a series of meta-regression analyses involving ≤199 477 participants in 63 studies. We then evaluated the effect of these polymorphisms on the odds of coronary heart disease in 22,223 case and 64,762 control subjects and compared it with the effect of lower SBP observed in both prospective cohort studies and blood pressure-lowering randomized trials. All 12 polymorphisms were associated with both lower SBP and a slower age-related rise in SBP. The weighted mean effect of these 12 polymorphisms was associated with a 0.32-mm Hg lower SBP (P=1.79×10(-7)) and a 0.093-mm Hg/decade slower age-related rise in SBP (P=3.05×10(-5)). The effect of long-term exposure to lower SBP on coronary heart disease mediated by these polymorphisms was 2-fold greater than that observed in prospective cohort studies (P=0.006) and 3-fold greater than that observed in short-term blood pressure treatment trials (P=0.001). We conclude therefore that SBP seems to be causally associated with the rate of rise in SBP with age and has a cumulative effect on the risk of coronary heart disease.

  11. [Systolic blood pressure and functional outcome in patients with acute stroke: a Mexican registry of acute cerebrovascular disease (RENAMEVASC)].

    Science.gov (United States)

    Baños-González, Manuel; Cantú-Brito, Carlos; Chiquete, Erwin; Arauz, Antonio; Ruiz-Sandoval, José Luís; Villarreal-Careaga, Jorge; Barinagarrementeria, Fernando; Lozano, José Juan

    2011-01-01

    To analyze the association between the admission systolic blood pressure (SBP) and 30-day outcome in patients with acute cerebrovascular disease. The REgistro NAcional Mexicano de Enfermedad VAScular Cerebral (RENAMEVASC) is a hospital-based multicenter registry performed between November 2002 and October 2004. A total of 2000 patients with clinical syndromes of acute cerebrovascular disease confirmed by neuroimaging were registered. The modified Rankin scale was used for outcome stratification. We analyzed 1721 patients who had registered their SBP: 78 (4.5%) had transient ischemic attack, 894 (51.9%) brain infarction, 534 (30.9%) intracerebral hemorrhage, 165 (9.6%) subarachnoid hemorrhage and 50 (2.9%) cerebral venous thrombosis. Among 1036 (60.2%) patients with the antecedent of hypertension, only 32.4% had regular treatment. The 30-day case fatality rate presented a J pattern with respect to SBP, so that the risk of death was highest in 65 years (RR: 2.16, IC 95%: 1.74 - 2.67). Both hypotension and significant arterial hypertension at hospital admission are associated with an adverse outcome after acute cerebrovascular disease. Nevertheless, a good functional outcome can be attained in a wide range of SBP.

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

    Institute of Scientific and Technical Information of China (English)

    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.

  13. Oral supplementation with glycine reduces oxidative stress in patients with metabolic syndrome, improving their systolic blood pressure.

    Science.gov (United States)

    Díaz-Flores, Margarita; Cruz, Miguel; Duran-Reyes, Genoveva; Munguia-Miranda, Catarina; Loza-Rodríguez, Hilda; Pulido-Casas, Evelyn; Torres-Ramírez, Nayeli; Gaja-Rodriguez, Olga; Kumate, Jesus; Baiza-Gutman, Luis Arturo; Hernández-Saavedra, Daniel

    2013-10-01

    Reactive oxygen species derived from abdominal fat and uncontrolled glucose metabolism are contributing factors to both oxidative stress and the development of metabolic syndrome (MetS). This study was designed to evaluate the effects of daily administration of an oral glycine supplement on antioxidant enzymes and lipid peroxidation in MetS patients. The study included 60 volunteers: 30 individuals that were supplemented with glycine (15 g/day) and 30 that were given a placebo for 3 months. We analysed thiobarbituric acid reactive substances (TBARS) and S-nitrosohemoglobin (SNO-Hb) in plasma; the enzymatic activities of glucose-6-phosphate dehydrogenase (G6PD), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) in erythrocytes; and the expression of CAT, GPX, and SOD2 in leukocytes. Individuals treated with glycine showed a 25% decrease in TBARS compared with the placebo-treated group. Furthermore, there was a 20% reduction in SOD-specific activity in the glycine-treated group, which correlated with SOD2 expression. G6PD activity and SNO-Hb levels increased in the glycine-treated male group. Systolic blood pressure (SBP) also showed a significant decrease in the glycine-treated men (p = 0.043). Glycine plays an important role in balancing the redox reactions in the human body, thus protecting against oxidative damage in MetS patients.

  14. Management of acute heart failure and the effect of systolic blood pressure on the use of intravenous therapies

    Science.gov (United States)

    Harjola, Veli-Pekka; Tolonen, Jukka; Siirilä-Waris, Krista; Nieminen, Markku S; Lassus, Johan

    2013-01-01

    Aims: To examine the use of the treatments for acute heart failure (AHF) recommended by ESC guidelines in different clinical presentations and blood pressure groups. Methods: The use of intravenous diuretics, nitrates, opioids, inotropes, and vasopressors as well as non-invasive ventilation (NIV) was analysed in 620 patients hospitalized due to AHF. The relation between AHF therapies and clinical presentation, especially systolic blood pressure (SBP) on admission, was also assessed. Results: Overall, 76% of patients received i.v. furosemide, 42% nitrates, 29% opioids, 5% inotropes and 7% vasopressors, and 24% of patients were treated with NIV. Furosemide was the most common treatment in all clinical classes and irrespective of SBP on admission. Nitrates were given most often in pulmonary oedema and hypertensive AHF. Overall, only SBP differed significantly between patients with and without the studied treatments. SBP was higher in patients treated with nitrates than in those who were not (156 vs. 141 mmHg, p<0.001). Still, only one-third of patients presenting acute decompensated heart failure and SBP over 120 mmHg were given nitrates. Inotropes and vasopressors were given most frequently in cardiogenic shock and pulmonary oedema, and their use was inversely related to initial SBP (p<0.001). NIV was used only in half of the cardiogenic shock and pulmonary oedema patients. Conclusions: The management of AHF differs between ESC clinical classes and the use of i.v. vasoactive therapies is related to the initial SBP. However, there seems to be room for improvement in administration of vasodilators and NIV. PMID:24222833

  15. Comparison between waist and mid-upper arm circumferences in influencing systolic blood pressure in adolescence: the SHARP (Sardinian Hypertensive Adolescent Research Programme study

    Directory of Open Access Journals (Sweden)

    Pier Paolo Bassareo

    2013-06-01

    Full Text Available Background: The correlation between high blood pressure (BP and overweight in children is widely acknowledged, although the role of body fat distribution in this association remains to be fully elucidated. The aim of this study was to investigate the role of abdominal (central and mid-upper arm (peripheral adiposity in association with BP. Methods: 839 adolescents of both genders took part in the SHARP (Sardinian Hypertensive Adolescent Research Programme study. BP, waist circumference (WC, mid-upper arm circumference (MUAC, body mass index (BMI and heart rate were measured. Results: 89 out of 839 subjects were hypertensive (10.6%: 44 males and 45 females. Isolated systolic hypertension: 4.2%; isolated diastolic hypertension: 4.9%; combined systolic and diastolic hypertension: 1.5%. In univariate analysis, WC and MUAC correlated with systolic (p < 0.0001 and p < 0.0007, respectively, but not with diastolic BP. In multiple longitudinal regression analysis, WC and MUAC were the strongest independent predictors of systolic BP over time. Furthermore, a significant increase of systolic BP was observed throughout all age-adjusted quintiles of WC (p < 0.001, while a similar increase was revealed only for the first four quintiles of MUAC (p < 0.001. Higher quintiles of central adiposity were associated with a higher prevalence of elevated systolic BP (p < 0.001, while no similar relationship was detected for MUAC. Conclusions: in adolescence, central and periph- eral distribution of body fat is associated with normal systolic BP, irrespective of BMI, with WC alone being correlated to hypertension. Proceedings of the 9th International Workshop on Neonatology · Cagliari (Italy · October 23rd-26th, 2013 · Learned lessons, changing practice and cutting-edge research

  16. Low thyroid function leads to cardiac atrophy with chamber dilatation, impaired myocardial blood flow, loss of arterioles, and severe systolic dysfunction.

    Science.gov (United States)

    Tang, Yi-Da; Kuzman, James A; Said, Suleman; Anderson, Brent E; Wang, Xuejun; Gerdes, A Martin

    2005-11-15

    Although thyroid dysfunction has been linked to heart failure, it is not clear whether hypothyroidism alone can cause heart failure. Hypothyroidism was induced in adult rats by treatment with 0.025% propylthiouracil (PTU) for 6 weeks (PTU-S) and 1 year (PTU-L). Echocardiographic measurements, left ventricular (LV) hemodynamics, isolated myocyte length (KOH method), myocardial blood flow (fluorescent microspheres), arteriolar morphometry, and gene expression (Western blot) were determined. Heart weight, heart rate, LV systolic blood pressure, LV ejection fraction, LV fractional shortening, and systolic wall thickness were reduced in PTU-S and PTU-L rats. LV internal diameter in systole increased by 40% in PTU-S and 86% in PTU-L. LV internal dimension in diastole was increased in PTU-S and PTU-L rats, but only PTU-L rats showed a significant increase in myocyte length due to series sarcomere addition. Resting and maximum (adenosine) myocardial blood flow were reduced in both PTU-S and PTU-L rats. Impaired blood flow was due to a large reduction in arteriolar length density and small arterioles in PTU-S and PTU-L (Pcardiac mass. Chamber dilatation in PTU-L rats was due to series sarcomere addition, typical of heart failure. Hypothyroidism resulted in impaired myocardial blood flow due to a dramatic loss of arterioles. Thus, we have identified 2 important new mechanisms by which low thyroid function may lead to heart failure.

  17. Absence of sex differences in systolic blood pressure and heart rate responses to exercise in healthy young adults.

    Science.gov (United States)

    Maruf, F A; Ogochukwu, U N; Dim, P A; Alada, A Ra

    2012-06-07

    The influence of sex on systolic blood pressure (SBP) and heart rate (HR) responses associated with cardiovascular morbidity, in healthy young adults was determined in ninety healthy young adults (47 females and 43 males) exercised using Bruce protocol. SBP and HR were measured pre- and post-exercise, and during recovery. SBPresponse (peak minus pre-exercise SBP), %SBPresponse [(peak minus pre-exercise SBP)÷pre-exercise SBP]x100, SBP3 (SBP 3 minutes into recovery), SBP4 (SBP 4 minutes into recovery), SBP3:peak (SBP3÷peak SBP), %SBPd3 [(peak SBP minus SBP 3 minutes into recovery)x peak SBP]x100, %SBPd4 [(peak SBP minus SBP 4 minutes into recovery)x peak SBP]X100, HRresponse (Peak HR minus pre-exercise HR), %HRresponse [(peak HR minus pre-exercise HR)÷pre-exercise HR]x 100, HR3 (HR 3 minutes into recovery), HR4 (HR 4 minutes into recovery), %HRd3 [(peak HR minus HR 3 minutes into recovery)÷peak HR]x100, %HRd4 [(peak HR minus HR 4 minutes into recovery)÷peak HR]X100, and HR50-70 (HR between 50th and 70th seconds into recovery) were derived from SBP and HR measurements. SBPpeak, HRresponse and %HRresponse were higher in males than in females whereas, SBPresponse, %SBPresponse and HRpeak were not different. There were no significant differences in the post-exercise SBP and HR responses of males and females except for SBP3, SBP4, HR3 and HR4. After adjusting for exercise duration, body mass index (BMI), and resting SBP and HR, these variables became similar. Sex differences in some SBP and HR responses to exercise, become nonexistent after adjusting for BMI, exercise duration, and resting SBP and HR.

  18. Casein-Derived Lactotripeptides Reduce Systolic and Diastolic Blood Pressure in a Meta-Analysis of Randomised Clinical Trials

    Directory of Open Access Journals (Sweden)

    Ágnes A. Fekete

    2015-01-01

    Full Text Available There is an urgent need to treat individuals with high blood pressure (BP with effective dietary strategies. Previous studies suggest a small, but significant decrease in BP after lactotripeptides (LTP ingestion, although the data are inconsistent. The study aim was to perform a comprehensive meta-analysis of data from all relevant randomised controlled trials (RCT. Medline, Cochrane library, EMBASE and Web of Science were searched until May 2014. Eligibility criteria were RCT that examined the effects of LTP on BP in adults, with systolic BP (SBP and diastolic BP (DBP as outcome measures. Thirty RCT met the inclusion criteria, which resulted in 33 sets of data. The pooled treatment effect for SBP was −2.95 mmHg (95% CI: −4.17, −1.73; p < 0.001, and for DBP was −1.51 mmHg (95% CI: −2.21, −0.80; p < 0.001. Sub-group analyses revealed that reduction of BP in Japanese studies was significantly greater, compared with European studies (p = 0.002 for SBP and p < 0.001 for DBP. The 24-h ambulatory BP (AMBP response to LTP supplementation was statistically non-significant (p = 0.101 for SBP and p = 0.166 for DBP. Both publication bias and “small-study effect” were identified, which shifted the treatment effect towards less significant SBP and non-significant DBP reduction after LTP consumption. LTP may be effective in BP reduction, especially in Japanese individuals; however sub-group, meta-regression analyses and statistically significant publication biases suggest inconsistencies.

  19. Relation of Body's Lean Mass, Fat Mass, and Body Mass Index With Submaximal Systolic Blood Pressure in Young Adult Men.

    Science.gov (United States)

    Prasad, Vivek K; Drenowatz, Clemens; Hand, Gregory A; Lavie, Carl J; Sui, Xuemei; Demello, Madison; Blair, Steven N

    2016-02-01

    We examined the association of body composition and body mass index (BMI) with submaximal systolic blood pressure (SSBP) among young adult men. The analysis included 211 men with BMI between 20 and 35 kg/m(2). Total lean mass and fat mass were measured using dual x-ray absorptiometry and lean mass percentage was calculated from the total lean mass. Fat mass index (FMI) and BMI were calculated using height and weight (total fat mass and total weight, respectively) measurements. SSBP was measured at each stage of a graded exercise test. Quintiles of lean mass percentage, FMI, and BMI were created with quintile 1 the lowest and quintile 5 the highest lean mass percentage, FMI, and BMI. Compared with men in lean mass percentage quintile 1, those in quintiles 2, 3, and 4 had significantly lower SSBP, whereas there was no significant difference in SSBP between quintile 1 and 5 at 6, 8, and 10 minutes. Compared with men in FMI quintile 5, those in quintiles 2, 3, and 4 had significantly lower SSBP, whereas there was no significant difference in SSBP between quintile 1 and 5. SSBP among men in lean mass percentage quintile 5 and FMI quintile 1 were still less than lean mass percentage quintile 1 and FMI quintile 5, respectively. There were no significant differences in SSBP across BMI quintiles 1 to 4 but a significantly higher SSBP in quintile 5 compared with quintiles 1 to 4. In conclusion, there was a J-curve pattern between SSBP and components of body composition, whereas, a linear relation between SSBP and BMI.

  20. Habitual exercise decreases systolic blood pressure during low-intensity resistance exercise in healthy middle-aged and older individuals.

    Science.gov (United States)

    Otsuki, Takeshi; Kotato, Takahiro; Zempo-Miyaki, Asako

    2016-10-01

    Since aerobic exercise (e.g., walking) and resistance exercise (e.g., lifting objects and mopping) are both parts of the activities of daily living, an exaggerated elevation in systolic blood pressure (SBP) during aerobic and resistance exercise is an early marker of cardiovascular disease. This study investigated the effects of habitual exercise on SBP during low-intensity resistance exercise using both cross-sectional and interventional approaches. First, in 57 normotensive women (61.9 ± 1.0 yr of age), daily physical activity level, as assessed by triaxial accelerometry, was correlated with SBP during resistance exercise at 20 and 40% of the 1 repetition maximum (r = -0.408 and r = -0.348, respectively). Maximal oxygen uptake was correlated with SBP during exercise at 20% (r = -0.385) and 40% (r = -0.457). Physical activity level or maximal oxygen uptake was identified as a predictor of SBP during the exercise in stepwise regression analysis, independent of SBP at rest and other factors (R(2) = 0.729-0.781). Second, 66 men and women (64.6 ± 0.9 yr of age) participated in a 6-wk intervention as a part of the training (walking, 4.3 ± 0.3 days/wk, 55.6 ± 4.1 min/day, 70.7 ± 1.2% of maximal heart rate) or control group. SBP during resistance exercise in the training group decreased after the intervention (before vs. after: 20%, 143 ± 4 vs. 128 ± 4 mmHg; and 40%, 148 ± 5 vs. 134 ± 4 mmHg). In the control group, there were no significant differences in SBP before and after the intervention. SBP during resistance exercise after the intervention was lower in the training group relative to the control group. These results suggest that habitual exercise decreases SBP during low-intensity resistance exercise. Copyright © 2016 the American Physiological Society.

  1. Elevation in systolic blood pressure during heart failure hospitalization is associated with increased short and long-term mortality

    Science.gov (United States)

    Segal, Omer; Segal, Gad; Leibowitz, Avshalom; Goldenberg, Ilan; Grossman, Ehud; Klempfner, Robert

    2017-01-01

    Abstract The relationship between systolic blood pressure (SBP) change during hospitalization of patients with heart failure (HF) and clinical outcomes has never been thoroughly investigated. A total of 3393 patients hospitalized with HF, from 25 hospitals in Israel, were enrolled. The SBP change was calculated by subtracting the discharge SBP values from the admission values and then divided into quartiles of SBP change. We compared the group with upper quartile SBP change to the lower 3 quartiles of change. Both groups had largely similar demographics and clinical characteristics. All-cause mortality rate was 24% at 1-year and 82.6% at 10-years, whereas patients in the upper SBP change group had significantly higher cumulative mortality probability at 1-year (30% vs 22%; log-rank P <0.001), and at 10-years (86% vs 82%; log-rank P <0.001). Multivariate Cox proportional hazard analysis adjusted for comorbidities demonstrated that patients in the upper SBP change quartile have an independent 17% higher mortality risk at 10-years [hazard ratio (HR) 1.17; 95% confidence interval (CI) 1.08–1.28]. Subgroup analysis demonstrated that mortality risk was more pronounced in patients with preserved ejection fraction and in the subgroup with admission SBP ≥140 mm Hg. SBP change is significantly associated with 1- and 10-year all-cause mortality, as an increased SBP change is associated with worse prognosis. We believe that this readily available marker might facilitate risk stratification of patients and possibly improve care. PMID:28151864

  2. Effect of room temperature on tests for diagnosing vibration-induced white finger: finger rewarming times and finger systolic blood pressures.

    Science.gov (United States)

    Ye, Ying; Griffin, Michael J

    2017-08-01

    This study investigates the effects of room temperature on two standard tests used to assist the diagnosis of vibration-induced white finger (VWF): finger rewarming times and finger systolic blood pressures. Twelve healthy males and twelve healthy females participated in four sessions to obtain either finger skin temperatures (FSTs) during cooling and rewarming of the hand or finger systolic blood pressures (FSBPs) after local cooling of the fingers to 15 and 10 °C. The measures were obtained with the room temperature at either 20 or 28 °C. There were lower baseline finger skin temperatures, longer finger rewarming times, and lower finger systolic blood pressures with the room temperature at 20 than 28 °C. However, percentage reductions in FSBP at 15 and 10 °C relative to 30 °C (i.e. %FSBP) did not differ between the two room temperatures. Females had lower baseline FSTs, longer rewarming times, and lower FSBPs than males, but %FSBPs were similar in males and females. Finger rewarming times after cold provocation are heavily influenced by room temperature and gender. For evaluating peripheral circulatory function using finger rewarming times, the room temperature must be strictly controlled, and a different diagnostic criterion is required for females. The calculation of percentage changes in finger systolic blood pressure at 15 and 10 °C relative to 30 °C reduces effects of both room temperature and gender, and the test may be used in conditions where the ±1 °C tolerance on room temperature required by the current standard cannot be achieved.

  3. Low Systolic Blood Pressure and Mortality From All-Cause and Vascular Diseases Among the Rural Elderly in Korea; Kangwha Cohort Study

    OpenAIRE

    Yi, Sang-Wook; Hong, Seri; Ohrr, Heechoul

    2015-01-01

    Abstract The association between low systolic blood pressure (SBP) and vascular diseases is unclear. The aim of this study was to prospectively examine the association between SBP, especially low SBP, and mortality from all causes and vascular diseases among the elderly in Korea. Six thousand two hundred ninety four residents in a rural community were followed-up for deaths from 1985 to 2008. The adjusted hazard ratios (aHR) and 95% confidence intervals were calculated by Cox proportional haz...

  4. Clinical characteristics and short-term outcomes in patients with elevated admission systolic blood pressure after acute ST-elevation myocardial infarction: a population-based study

    OpenAIRE

    Huang, Bi; Yang, Yanmin; Zhu, Jun; Liang,Yan; Tan, Huiqiong

    2014-01-01

    Objective Prognostic value of lower admission systolic blood pressure (SBP) in patients with acute myocardial infarction has been confirmed, but the impact of elevated admission SBP on short-term outcomes has been evaluated only by a limited number of studies and they have reported conflicting results. The aim of our study was to investigate the characteristics and short-term outcomes in patients with elevated admission SBP after ST-elevation myocardial infarction (STEMI). Design A population...

  5. Functional epistatic interaction between rs6046G>A in F7 and rs5355C>T in SELE modifies systolic blood pressure levels.

    Science.gov (United States)

    El Shamieh, Said; Ndiaye, Ndeye Coumba; Stathopoulou, Maria G; Murray, Helena A; Masson, Christine; Lamont, John V; Fitzgerald, Peter; Benetos, Athanase; Visvikis-Siest, Sophie

    2012-01-01

    Although numerous genetic studies have been performed, only 0.9% of blood pressure phenotypic variance has been elucidated. This phenomenon could be partially due to epistatic interactions. Our aim was to identify epistatic interaction(s) associated with blood pressure levels in a pre-planned two-phase approach. In a discovery cohort composed of 3,600 French individuals, we found rs6046A allele in F7 associated with decreased blood pressure levels (P≤3.7×10(-3)) and rs5355T allele in SELE associated with decreased diastolic blood pressure levels (P = 5×10(-3)). Both variants interacted in order to influence blood pressure levels (P≤0.048). This interaction was replicated with systolic blood pressure in 4,620 additional European individuals (P = 0.03). Similarly, in this replication cohort, rs6046A was associated with decreased blood pressure levels (P≤8.5×10(-4)). Furthermore, in peripheral blood mononuclear cells of a subsample of 90 supposed healthy individuals, we found rs6046A positively associated with NAMPT mRNA levels (P≤9.1×10(-5)), suggesting an eventual involvement of NAMPT expression in blood pressure regulation. Confirming this hypothesis, further transcriptomic analyses showed that increased NAMPT mRNA levels were positively correlated with ICAM1, SELL, FPR1, DEFA1-3, and LL-37 genes expression (P≤5×10(-3)). The last two mRNA levels were positively associated with systolic blood pressure levels (P≤0.01) and explained 4% of its phenotypic variation. These findings reveal the importance of epistatic interactions in blood pressure genetics and give new insights for the role of inflammation in its complex regulation.

  6. Ambulatory Hypertension Subtypes and 24-Hour Systolic and Diastolic Blood Pressure as Distinct Outcome Predictors in 8341 Untreated People Recruited From 12 Populations

    DEFF Research Database (Denmark)

    Li, Yan; Wei, Fang-Fei; Thijs, Lutgarde

    2014-01-01

    BACKGROUND: Data on risk associated with 24-hour ambulatory diastolic (DBP24) versus systolic (SBP24) blood pressure are scarce. METHODS AND RESULTS: We recorded 24-hour blood pressure and health outcomes in 8341 untreated people (mean age, 50.8 years; 46.6% women) randomly recruited from 12...... populations. We computed hazard ratios (HRs) using multivariable-adjusted Cox regression. Over 11.2 years (median), 927 (11.1%) participants died, 356 (4.3%) from cardiovascular causes, and 744 (8.9%) experienced a fatal or nonfatal cardiovascular event. Isolated diastolic hypertension (DBP24≥80 mm Hg) did...

  7. Low systolic blood pressure and mortality from all-cause and vascular diseases among the rural elderly in Korea; Kangwha cohort study.

    Science.gov (United States)

    Yi, Sang-Wook; Hong, Seri; Ohrr, Heechoul

    2015-01-01

    The association between low systolic blood pressure (SBP) and vascular diseases is unclear. The aim of this study was to prospectively examine the association between SBP, especially low SBP, and mortality from all causes and vascular diseases among the elderly in Korea. Six thousand two hundred ninety four residents in a rural community were followed-up for deaths from 1985 to 2008. The adjusted hazard ratios (aHR) and 95% confidence intervals were calculated by Cox proportional hazard model. A stratified analysis was conducted by age at enrollment. Among the elderly aged 65 and above, the lowest SBP (100 mm Hg) group had an elevated aHR for mortality from vascular diseases (aHR = 2.1, 95% CI = 1.2-3.9) including stroke (aHR = 2.4, 95% CI = 0.9-6.3) and ischemic heart diseases (aHR = 5.1, 95% CI = 1.0-26.0) compared to those with SBP of 100-119 mm Hg, while higher SBP was associated with higher mortality. This J-curve association was generally maintained when analysis was restricted to those with fair or good self-rated health, or those with no known vascular diseases. In people below 65, increasing SBP nearly monotonically increased the mortality from all-cause and vascular diseases. Our results suggest that elderly persons with low SBP should be treated with caution, since low SBP may increase vascular mortality.

  8. Low systolic blood pressure and mortality from all causes and vascular diseases among older middle-aged men: Korean Veterans Health Study.

    Science.gov (United States)

    Yi, Sang-Wook; Ohrr, Heechoul

    2015-03-01

    Recently, low systolic blood pressure (SBP) was found to be associated with an increased risk of death from vascular diseases in a rural elderly population in Korea. However, evidence on the association between low SBP and vascular diseases is scarce. The aim of this study was to prospectively examine the association between low SBP and mortality from all causes and vascular diseases in older middle-aged Korean men. From 2004 to 2010, 94 085 Korean Vietnam War veterans were followed-up for deaths. The adjusted hazard ratios (aHR) were calculated using the Cox proportional hazard model. A stratified analysis was conducted by age at enrollment. SBP was self-reported by a postal survey in 2004. Among the participants aged 60 and older, the lowest SBP (low SBP was weaker than that in those aged 60 years or older. Our findings suggest that low SBP (<90 mmHg) may increase vascular mortality in Korean men aged 60 years or older.

  9. Effects of aliskiren- and ramipril-based treatment on central aortic blood pressure in elderly with systolic hypertension: a substudy of AGELESS

    Directory of Open Access Journals (Sweden)

    Baschiera F

    2014-06-01

    Full Text Available Fabio Baschiera,1 William Chang,2 Patrick Brunel1 On behalf of the AGELESS Study Group 1Novartis Pharma AG, Basel, Switzerland; 2Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA Background: Systolic hypertension is the most common form of hypertension in elderly patients. There is increasing evidence that measurement of central aortic pressure (CAP better accounts for cardiovascular risk than brachial blood pressure (BP. The Aliskiren for GEriatric LowEring of SyStolic hypertension (AGELESS study in elderly patients with systolic hypertension showed that aliskiren-based therapy provided greater reductions in peripheral BP than ramipril-based therapy over 12 and 36 weeks of treatment. Here, we present CAP results in a substudy of elderly patients from the AGELESS study. Methods: This was a post hoc analysis of a 36-week, randomized, double-blind, parallel-group, active-controlled, optional-titration study in patients ≥65 years of age with systolic BP ≥140 mmHg. Changes in both central and peripheral BP and pulse pressure (PP and changes in systolic and PP amplification ratios from baseline to the week 36 end point with aliskiren-based versus ramipril-based therapy were analyzed. Results: Of the 901 patients randomized in the overall study, 154 patients (aliskiren, n=78; ramipril, n=76 had CAP data. Numerically comparable reductions were seen for central aortic systolic pressure (CASP in aliskiren-based therapy (baseline: 143.7±15.0; week 36: −20.3±16.2 compared with ramipril-based therapy (baseline: 147.9±11.9; week 36: −20.7±14.6. However, for the change in central aortic diastolic pressure, the least squares mean between-treatment difference (−3.6 mmHg [95% confidence interval, −6.76, −0.43; P=0.0263] was in favor of aliskiren, while the other changes were comparable between the two groups with a trend in favor of aliskiren for CASP as well (−2.6 mmHg [95% confidence interval, −7.38, 2.19; P=0

  10. Hemodynamic variables during exercise in childhood and resting systolic blood pressure levels 6 years later in adolescence: the European Youth Heart Study

    DEFF Research Database (Denmark)

    Grøntved, Anders; Andresen, Brage Storstein; Møller, N C

    2011-01-01

    The aim of this study was to analyze whether systolic blood pressure (SBP), heart rate (HR) and rate pressure product (RPP) during exercise in childhood can predict resting SBP levels in adolescence independent of resting SBP and conventional cardiovascular risk factors. We studied this in a samp...... the prediction of future SBP levels during rest in adolescence independent of resting SBP and conventional cardiovascular risk factors.Journal of Human Hypertension advance online publication, 11 November 2010; doi:10.1038/jhh.2010.103....

  11. National, regional, and global trends in systolic blood pressure since 1980: systematic analysis of health examination surveys and epidemiological studies with 786 country-years and 5·4 million participants

    DEFF Research Database (Denmark)

    Danaei, Goodarz; Finucane, Mariel M; Lin, John K;

    2011-01-01

    Data for trends in blood pressure are needed to understand the effects of its dietary, lifestyle, and pharmacological determinants; set intervention priorities; and evaluate national programmes. However, few worldwide analyses of trends in blood pressure have been done. We estimated worldwide tre...... trends in population mean systolic blood pressure (SBP)....

  12. An Empirical Comparison of Joint and Stratified Frameworks for Studying G × E Interactions: Systolic Blood Pressure and Smoking in the CHARGE Gene-Lifestyle Interactions Working Group.

    Science.gov (United States)

    Sung, Yun Ju; Winkler, Thomas W; Manning, Alisa K; Aschard, Hugues; Gudnason, Vilmundur; Harris, Tamara B; Smith, Albert V; Boerwinkle, Eric; Brown, Michael R; Morrison, Alanna C; Fornage, Myriam; Lin, Li-An; Richard, Melissa; Bartz, Traci M; Psaty, Bruce M; Hayward, Caroline; Polasek, Ozren; Marten, Jonathan; Rudan, Igor; Feitosa, Mary F; Kraja, Aldi T; Province, Michael A; Deng, Xuan; Fisher, Virginia A; Zhou, Yanhua; Bielak, Lawrence F; Smith, Jennifer; Huffman, Jennifer E; Padmanabhan, Sandosh; Smith, Blair H; Ding, Jingzhong; Liu, Yongmei; Lohman, Kurt; Bouchard, Claude; Rankinen, Tuomo; Rice, Treva K; Arnett, Donna; Schwander, Karen; Guo, Xiuqing; Palmas, Walter; Rotter, Jerome I; Alfred, Tamuno; Bottinger, Erwin P; Loos, Ruth J F; Amin, Najaf; Franco, Oscar H; van Duijn, Cornelia M; Vojinovic, Dina; Chasman, Daniel I; Ridker, Paul M; Rose, Lynda M; Kardia, Sharon; Zhu, Xiaofeng; Rice, Kenneth; Borecki, Ingrid B; Rao, Dabeeru C; Gauderman, W James; Cupples, L Adrienne

    2016-07-01

    Studying gene-environment (G × E) interactions is important, as they extend our knowledge of the genetic architecture of complex traits and may help to identify novel variants not detected via analysis of main effects alone. The main statistical framework for studying G × E interactions uses a single regression model that includes both the genetic main and G × E interaction effects (the "joint" framework). The alternative "stratified" framework combines results from genetic main-effect analyses carried out separately within the exposed and unexposed groups. Although there have been several investigations using theory and simulation, an empirical comparison of the two frameworks is lacking. Here, we compare the two frameworks using results from genome-wide association studies of systolic blood pressure for 3.2 million low frequency and 6.5 million common variants across 20 cohorts of European ancestry, comprising 79,731 individuals. Our cohorts have sample sizes ranging from 456 to 22,983 and include both family-based and population-based samples. In cohort-specific analyses, the two frameworks provided similar inference for population-based cohorts. The agreement was reduced for family-based cohorts. In meta-analyses, agreement between the two frameworks was less than that observed in cohort-specific analyses, despite the increased sample size. In meta-analyses, agreement depended on (1) the minor allele frequency, (2) inclusion of family-based cohorts in meta-analysis, and (3) filtering scheme. The stratified framework appears to approximate the joint framework well only for common variants in population-based cohorts. We conclude that the joint framework is the preferred approach and should be used to control false positives when dealing with low-frequency variants and/or family-based cohorts.

  13. The effects of increasing levels of dietary garlic bulb on growth performance, systolic blood pressure, hematology, and ascites syndrome in broiler chickens.

    Science.gov (United States)

    Varmaghany, Saifali; Karimi Torshizi, Mohammad Amir; Rahimi, Shaban; Lotfollahian, Houshang; Hassanzadeh, Mohammad

    2015-08-01

    The effects of dietary garlic bulb were studied separately on hematological parameters, ascites incidence, and growth performance of an ascites susceptible broiler hybrid under both standard temperature conditions ( STC: ) and cold temperature conditions ( CTC: ). A total of 336 one-day-old male broiler chickens were allocated to 4 experimental groups with 4 replicates of 21 birds each under STC. In addition, the same grouping with another 336 birds was used for CTC. Under CTC, the birds were exposed to cold temperatures for induction of ascites. Experimental groups were defined by the inclusion of 0 (control), 5, 10 or 15 g/kg garlic bulbs in the diets under both STC and CTC. Growth performance, systolic blood pressure (as a measure of systemic arterial blood pressure), physiological and biochemical parameters, as well as ascites indices (right ventricle [ RV: ], total ventricle [ TV: ] weights, and RV/TV: ) were evaluated. Systolic blood pressure was determined using an indirect method with a sphygmomanometer, a pediatric cuff, and a Doppler device. The final body weight decreased quadratically (P = 0.003), with increasing garlic bulb levels in the diets under STC. The feed conversion ratio showed no significant differences among all groups under both STC and CTC. No significant differences were observed in total mortality and ascites-related mortality in all groups under STC, although total mortality (L: P = 0.01; Q: P = 0.001) and ascites-related mortality (L: P = 0.007; Q: P = 0.001) were significantly different among the diets under CTC. Under STC, the systolic blood pressure, packed cell volume, hemoglobin, RV, TV, and RV/TV did not vary significantly among the diets. However, red blood cell count and erythrocyte osmotic fragility decreased linearly (P pressure, packed cell volume, red blood cell count, and erythrocyte osmotic fragility decreased (P < 0.05) with increasing garlic levels. It is concluded that the inclusion of 5 g/kg garlic

  14. Interdialytic weight gain, systolic blood pressure, serum albumin, and C-reactive protein levels change in chronic dialysis patients prior to death.

    Science.gov (United States)

    Usvyat, Len A; Barth, Claudia; Bayh, Inga; Etter, Michael; von Gersdorff, Gero D; Grassmann, Aileen; Guinsburg, Adrian M; Lam, Maggie; Marcelli, Daniele; Marelli, Cristina; Scatizzi, Laura; Schaller, Mathias; Tashman, Adam; Toffelmire, Ted; Thijssen, Stephan; Kooman, Jeroen P; van der Sande, Frank M; Levin, Nathan W; Wang, Yuedong; Kotanko, Peter

    2013-07-01

    Reports from a United States cohort of chronic hemodialysis patients suggested that weight loss, a decline in pre-dialysis systolic blood pressure, and decreased serum albumin may precede death. However, no comparative studies have been reported in such patients from other countries. Here we analyzed dynamic changes in these parameters in hemodialysis patients and included 3593 individuals from 5 Asian countries; 35,146 from 18 European countries; 8649 from Argentina; and 4742 from the United States. In surviving prevalent patients, these variables appeared to have notably different dynamics than in patients who died. While in all populations the interdialytic weight gain, systolic blood pressure, and serum albumin levels were stable in surviving patients, these indicators declined starting more than a year ahead in those who died with the dynamics similar irrespective of gender and geographic region. In European patients, C-reactive protein levels were available on a routine basis and indicated that levels of this acute-phase protein were low and stable in surviving patients but rose sharply before death. Thus, relevant fundamental biological processes start many months before death in the majority of chronic hemodialysis patients. Longitudinal monitoring of these dynamics may help to identify patients at risk and aid the development of an alert system to initiate timely interventions to improve outcomes.

  15. Efficacy of a classical antiobesity Unani pharmacopial formulation (Safoof-e-Muhazzil in systolic and diastolic blood pressure: A randomized, open-labeled, controlled clinical study

    Directory of Open Access Journals (Sweden)

    Asim Ali Khan

    2013-01-01

    Full Text Available The aim of this study is to evaluate the efficacy of a Unani formulation in hypertension. A total of 90 patients with total cholesterol level of more than 220 mg/dl with associated conditions were included in this study. A total of 30 patients having a mean systolic blood pressure (BP of 133.86 mmHg comprising Group A received Unani formulation Safoof-e-Muhazzil (SM in its classical powder form in the dose of 5 g twice a day orally. Group B comprising of 30 patients with a mean systolic BP of 133.13 mmHg received same drug, but in compressed tablet form in the same dosage, whereas, 30 patients comprising Group C with a mean systolic BP of 129.45 mmHg, received Atorvastatin 10 mg as a standard control. Patients were evaluated on each follow-up at 2 nd , 4 th and 6 th week. The mean systolic BP in Group A and B before treatment was 133.86 ± 3.028 mmHg and 133.13 ± 2.852 mmHg, which significantly decreased to 119.33 ± 1.922 mmHg (P < 0.001 and 119 ± 1.760 mmHg (P < 0.001 respectively. In the control Group C before treatment BP was 129.45 ± 2.499 mmHg and after treatment it significantly decreased to 124.34 ± 1.794 mmHg (P < 0.01. The percentage change after treatment was 10.85%, 10.61% and 3.94% respectively in each group. Mean diastolic BP in Group A and B before treatment was 85.06 ± 2.11 mmHg and 84.56 ± 1.5 mmHg, which significantly decreased to 79.06 ± 1.56 mmHg (P < 0.001 and 79.96 ± 1.15 mmHg (P < 0.001 respectively, BP before treatment in Group C was 83.23 ± 1.588 mmHg, which was decreased to 124.34 ± 1.794 mmHg (P < 0.01. The study results indicate that the test drug was quite effective in reducing both systolic as well as diastolic BP.

  16. Mediation and Moderation of the Association between Cynical Hostility and Systolic Blood Pressure in Low-Income Women

    Science.gov (United States)

    Versey, H. Shellae; Kaplan, George A.

    2012-01-01

    Hostility may be related to risk factors for cardiovascular disease (CVD), such as blood pressure. However, the process by which hostility affects blood pressure is not fully understood. The current study sought to evaluate abdominal obesity (waist-to-hip ratio [WHR]) as a potential mediator and modifier of the relationship between cynical…

  17. Very preterm birth is a risk factor for increased systolic blood pressure at a young adult age

    NARCIS (Netherlands)

    M.G. Keijzer-Veen (Mandy); A. Dülger (Arzu); F.W. Dekker (Friedo); J. Nauta (Jeroen); A.J. van der Heijden (Bert)

    2010-01-01

    textabstractChildren born very prematurely who show intrauterine growth retardation (IUGR) are suggested to be at risk of developing high blood pressure as adults. Renal function may already be impaired by young adult age. To study whether very preterm birth affects blood pressure in young adults, w

  18. Mediation and Moderation of the Association between Cynical Hostility and Systolic Blood Pressure in Low-Income Women

    Science.gov (United States)

    Versey, H. Shellae; Kaplan, George A.

    2012-01-01

    Hostility may be related to risk factors for cardiovascular disease (CVD), such as blood pressure. However, the process by which hostility affects blood pressure is not fully understood. The current study sought to evaluate abdominal obesity (waist-to-hip ratio [WHR]) as a potential mediator and modifier of the relationship between cynical…

  19. Systolic blood pressure control among individuals with Type 2 Diabetes: A comparative effectiveness analysis of three interventions

    Science.gov (United States)

    Intensive lifestyle management or frequent goal-based monitoring with pharmacological management can be successful strategies for blood pressure control in overweight and obese adults with type 2 diabetes....

  20. Systolic blood pressure reactions to acute stress are associated with future hypertension status in the Dutch Famine Birth Cohort Study

    OpenAIRE

    Carroll, Douglas; Ginty, Annie T; Painter, Rebecca C; Tessa J Roseboom; Phillips, Anna C.; de Rooij, Susanne R.

    2012-01-01

    These analyses examined the association between blood pressure reactions to acute psychological stress and subsequent hypertension status in a substantial Dutch cohort. Blood pressure was recorded during a resting baseline and during three acute stress tasks, Stroop colour word, mirror tracing and speech. Five years later, diagnosed hypertension status was determined by questionnaire. Participants were 453 (237 women) members of the Dutch Famine Birth Cohort. In analysis adjusting for a n...

  1. EXERCISE-INDUCED ACUTE CHANGES IN SYSTOLIC BLOOD PRESSURE DO NOT ALTER CHOROIDAL THICKNESS AS MEASURED BY A PORTABLE SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY DEVICE

    Science.gov (United States)

    ALWASSIA, AHMAD A.; ADHI, MEHREEN; ZHANG, JASON Y.; REGATIERI, CAIO V.; AL-QUTHAMI, ADEEB; SALEM, DEEB; FUJIMOTO, JAMES G.; DUKER, JAY S.

    2013-01-01

    Purpose To measure choroidal thickness in patients manifesting an acute change in systemic arterial blood pressure using a portable spectral-domain optical coherence tomography device (iVue). Methods Fifteen patients (15 eyes) undergoing cardiac exercise stress testing were scanned using a portable spectral-domain optical coherence tomography system (iVue). Two scan protocols were used: cross line scan for measuring choroidal thickness and the retina map scan to measure retinal thickness. Each patient was scanned before and within 3 minutes after the stress test. Blood pressure was measured at the same time as the acquisition of the scans. Choroidal thickness was measured from the posterior edge of the retinal pigment epithelium to the choroid–sclera junction at 500-μm intervals up to 1,000 μm temporal and nasal to the fovea. Retinal thickness was measured by an automated software. All choroidal thickness measurements were performed by two independent observers. Results Fifteen patients (15 eyes) with a mean age of 60.6 (±10.4 years) were scanned. There was a significant increase in systolic but not diastolic pressure after stress testing (P choroidal thickness measurements showed no significant difference before and after exercise stress testing (P > 0.05). In addition, there was no significant difference in retinal thickness before and after stress testing measurements (P > 0.05). Conclusion There was no change in choroidal thickness or retinal thickness, despite an acute change in the systemic systolic blood pressure induced by exercise. PMID:22869027

  2. Clock Genes Explain a Large Proportion of Phenotypic Variance in Systolic Blood Pressure and This Control Is Not Modified by Environmental Temperature.

    Science.gov (United States)

    Dashti, Hassan S; Aslibekyan, Stella; Scheer, Frank A J L; Smith, Caren E; Lamon-Fava, Stefania; Jacques, Paul; Lai, Chao-Qiang; Tucker, Katherine L; Arnett, Donna K; Ordovás, José M

    2016-01-01

    Diurnal variation in blood pressure (BP) is regulated, in part, by an endogenous circadian clock; however, few human studies have identified associations between clock genes and BP. Accounting for environmental temperature may be necessary to correct for seasonal bias. We examined whether environmental temperature on the day of participants' assessment was associated with BP, using adjusted linear regression models in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) (n = 819) and the Boston Puerto Rican Health Study (BPRHS) (n = 1,248) cohorts. We estimated phenotypic variance in BP by 18 clock genes and examined individual single-nucleotide polymorphism (SNP) associations with BP using an additive genetic model, with further consideration of environmental temperature. In GOLDN, each additional 1 °C increase in environmental temperature was associated with 0.18 mm Hg lower systolic BP [SBP; β ± SE = -0.18 ± 0.05 mm Hg; P = 0.0001] and 0.10mm Hg lower diastolic BP [DBP; -0.10 ± 0.03 mm Hg; P = 0.001]. Similar results were seen in the BPRHS for SBP only. Clock genes explained a statistically significant proportion of the variance in SBP [V G/V P ± SE = 0.071 ± 0.03; P = 0.001] in GOLDN, but not in the BPRHS, and we did not observe associations between individual SNPs and BP. Environmental temperature did not influence the identified genetic associations. We identified clock genes that explained a statistically significant proportion of the phenotypic variance in SBP, supporting the importance of the circadian pathway underlying cardiac physiology. Although temperature was associated with BP, it did not affect results with genetic markers in either study. Therefore, it does not appear that temperature measures are necessary for interpreting associations between clock genes and BP. Trials related to this study were registered at clinicaltrials.gov as NCT00083369 (Genetic and Environmental Determinants of Triglycerides) and NCT01231958 (Boston Puerto

  3. Time-updated systolic blood pressure and the progression of chronic kidney disease: Findings from the Chronic Renal Insufficiency Cohort (CRIC) Study

    Science.gov (United States)

    Anderson, Amanda H; Yang, Wei; Townsend, Raymond R; Pan, Qiang; Chertow, Glenn M; Kusek, John W; Charleston, Jeanne; He, Jiang; Kallem, RadhaKrishna; Lash, James P; Miller, Edgar R; Rahman, Mahboob; Steigerwalt, Susan; Weir, Matthew; Wright, Jackson T; Feldman, Harold I

    2015-01-01

    Background Blood pressure (BP) is often inadequately controlled in patients with chronic kidney disease (CKD). Previous reports of the longitudinal association between achieved level of BP and end-stage renal disease (ESRD) have not incorporated time-updated BP with appropriate adjustment for known confounders. Objective To assess the association between baseline and time-updated systolic BP (SBP) with the progression of CKD. Design Observational, prospective cohort study (ClinicalTrials.gov identifier: NCT00304148) Setting Seven US clinical centers Patients Participants of the Chronic Renal Insufficiency Cohort (CRIC) Study (N=3,708) followed for a median (25th, 75th percentiles) of 5.7 (4.6, 6.7) years Measurements The mean of three seated SBP measurements were used as the visit-specific SBP. SBP was time-updated as the mean of that visit and all prior visits. Outcomes were ESRD and the composite renal endpoint of ESRD (dialysis or transplantation) or halving of the estimated glomerular filtration rate (eGFR). Analyses investigating baseline and time-updated SBP utilized traditional Cox proportional hazards models and marginal structural models, respectively. Results SBP was ≥130 mmHg at all study visits in 19.2% of participants, and ≥140 mmHg in 10.6%. The hazard ratio (95% confidence interval) for ESRD among participants with SBP 130–139 mmHg, compared to SBP <120 mmHg, was 1.46 (1.13–1.88) using only baseline data, and was 2.37 (1.48–3.80) using all available time-updated data. Among those with SBP ≥140 mmHg, corresponding hazard ratios were 1.46 (1.18–1.88) and 3.37 (2.26–5.03), respectively. Limitations SBP was measured once annually, and the CRIC Study cohort is not a random sample. Conclusions Among participants in the CRIC Study, time-updated SBP over 130 mmHg was more strongly associated with progression of CKD than analyses based on baseline SBP. Funding The CRIC Study is funded under cooperative agreements from the National Institute of

  4. Regular cocaine use is associated with increased systolic blood pressure, aortic stiffness and left ventricular mass in young otherwise healthy individuals.

    Directory of Open Access Journals (Sweden)

    Rebecca Kozor

    Full Text Available BACKGROUND: The cardiovascular impact of cocaine use in otherwise healthy individuals who consider themselves 'social' users is not well established. METHODS/RESULTS: Twenty regular cocaine users and 20 control subjects were recruited by word-of-mouth. Cardiovascular magnetic resonance was performed to assess cardiac and vascular structure and function. Cocaine users had higher systolic blood pressure compared to non-users (134±11 vs 126±11 mmHg, p = 0.036, a finding independent of age, body surface area, smoking and alcohol consumption. Cocaine use was associated with increased arterial stiffness - reflected by reduced aortic compliance (1.3±0.2 vs 1.7±0.5 cm2×10-2.mmHg-1, p = 0.004, decreased distensibility (3.8±0.9 vs 5.1±1.4 mmHg-1.10-3, p = 0.001, increased stiffness index (2.6±0.6 vs 2.1±0.6, p = 0.005, and higher pulse wave velocity (5.1±0.6 vs 4.4±0.6 m.s-1, p = 0.001. This change in aortic stiffness was independent of vessel wall thickness. Left ventricular mass was 18% higher in cocaine users (124±25 vs 105±16 g, p = 0.01, a finding that was independent of body surface area, and left atrial diameter was larger in the user group than controls (3.8±0.6 vs 3.5±0.3 cm, p = 0.04. The increased left ventricular mass, systolic blood pressure and vascular stiffness measures were all associated with duration and/or frequency of cocaine use. No late gadolinium enhancement or segmental wall motion abnormalities were seen in any of the subjects. CONCLUSIONS: Compared with the non-user control cohort, cocaine users had increased aortic stiffness and systolic blood pressure, associated with greater left ventricular mass. These measures are all well known risk factors for premature cardiovascular events, highlighting the dangers of cocaine use, even in a 'social' setting, and have important public health implications.

  5. Right Heart End-Systolic Remodeling Index Strongly Predicts Outcomes in Pulmonary Arterial Hypertension: Comparison With Validated Models.

    Science.gov (United States)

    Amsallem, Myriam; Sweatt, Andrew J; Aymami, Marie C; Kuznetsova, Tatiana; Selej, Mona; Lu, HongQuan; Mercier, Olaf; Fadel, Elie; Schnittger, Ingela; McConnell, Michael V; Rabinovitch, Marlene; Zamanian, Roham T; Haddad, Francois

    2017-06-01

    Right ventricular (RV) end-systolic dimensions provide information on both size and function. We investigated whether an internally scaled index of end-systolic dimension is incremental to well-validated prognostic scores in pulmonary arterial hypertension. From 2005 to 2014, 228 patients with pulmonary arterial hypertension were prospectively enrolled. RV end-systolic remodeling index (RVESRI) was defined by lateral length divided by septal height. The incremental values of RV free wall longitudinal strain and RVESRI to risk scores were determined. Mean age was 49±14 years, 78% were female, 33% had connective tissue disease, 52% were in New York Heart Association class ≥III, and mean pulmonary vascular resistance was 11.2±6.4 WU. RVESRI and right atrial area were strongly connected to the other right heart metrics. Three zones of adaptation (adapted, maladapted, and severely maladapted) were identified based on the RVESRI to RV systolic pressure relationship. During a mean follow-up of 3.9±2.4 years, the primary end point of death, transplant, or admission for heart failure was reached in 88 patients. RVESRI was incremental to risk prediction scores in pulmonary arterial hypertension, including the Registry to Evaluate Early and Long-Term PAH Disease Management score, the Pulmonary Hypertension Connection equation, and the Mayo Clinic model. Using multivariable analysis, New York Heart Association class III/IV, RVESRI, and log NT-proBNP (N-Terminal Pro-B-Type Natriuretic Peptide) were retained (χ(2), 62.2; Pright heart metrics, RVESRI demonstrated the best test-retest characteristics. RVESRI is a simple reproducible prognostic marker in patients with pulmonary arterial hypertension. © 2017 American Heart Association, Inc.

  6. Relationships of the systolic blood pressure response during exercise with insulin resistance, obesity, and endurance fitness in men with type 2 diabetes mellitus.

    Science.gov (United States)

    Kumagai, S; Kai, Y; Hanada, H; Uezono, K; Sasaki, H

    2002-10-01

    The purpose of the present study was to investigate the relationships among the resting systolic (SBP) and diastolic blood pressure (DBP) or SBP response during exercise with insulin resistance evaluated by a homeostasis model (HOMA-IR), abdominal fat accumulation (visceral fat area [VFA], subcutaneous fat area [SFA]) by computed tomography (CT), and an estimation of the maximal oxygen uptake (V*O2max) in 63 Japanese middle-aged male patients with type 2 diabetes mellitus (type 2 DM). Body mass index (BMI) and waist-to-hip ratio (WHR) in type 2 DM subjects were significantly higher than in age-matched healthy male control subjects (n = 135) with normal glucose tolerance. Resting SBP (127.7 +/- 16.2 mm Hg v 119.4 +/- 13.0 mm Hg) and DBP (82.2 +/- 11.9mmHg v 76.8 +/- 9.4 mm Hg) levels, and the percentage of hypertension (20.6% v 1.5%) in type 2 DM subjects were significantly higher than in the control subjects (P cycle ergometer in 54 patients with type 2 DM only. The SBP was measured at 15-second intervals during exercise. The exercise intensity at the double product breaking point (DPBP), which strongly correlated with the exercise intensity at the lactate threshold, was used as an index for the SBP response to standardized exercise intensity. The SBP corresponding to exercise intensity at DPBP (SBP@DPBP) was evaluated as an index of the SBP response to standardized exercise intensity. The change in SBP (deltaSBP = SBP@DPBP - resting SBP) was significantly and positively associated with log area under the curve for glucose (log AUCPG) during a 75-g oral glucose tolerance test (OGTT). In addition, deltaSBP significantly and negatively correlated with the log area under the curve for insulin (log AUCIRI) and log AUCIRI/log AUCPG. Based on these results, insulin resistance was suggested to be independently associated with the resting DBP and SBP response to standardized exercise intensity in type 2 DM patients.

  7. Probing genetic overlap in the regulation of systolic and diastolic blood pressure in Danish and Chinese twins

    DEFF Research Database (Denmark)

    Li, Shuxia; Pang, Zengchang; Zhang, Dongfeng

    2014-01-01

    with Danish twins. The estimated contribution from unique environmental factors suggests that promoting healthy lifestyles may provide an efficient way of controlling high blood pressure, particularly in the Chinese population.Hypertension Research advance online publication, 15 May 2014; doi:10.1038/hr.2014.95....

  8. Association of genetic variation with systolic and diastolic blood pressure among African Americans : the Candidate Gene Association Resource study

    NARCIS (Netherlands)

    Fox, Ervin R.; Young, J. Hunter; Li, Yali; Dreisbach, Albert W.; Keating, Brendan J.; Musani, Solomon K.; Liu, Kiang; Morrison, Alanna C.; Ganesh, Santhi; Kutlar, Abdullah; Ramachandran, Vasan S.; Polak, Josef F.; Fabsitz, Richard R.; Dries, Daniel L.; Farlow, Deborah N.; Redline, Susan; Adeyemo, Adebowale; Hirschorn, Joel N.; Sun, Yan V.; Wyatt, Sharon B.; Penman, Alan D.; Palmas, Walter; Rotter, Jerome I.; Townsend, Raymond R.; Doumatey, Ayo P.; Tayo, Bamidele O.; Mosley, Thomas H.; Lyon, Helen N.; Kang, Sun J.; Rotimi, Charles N.; Cooper, Richard S.; Franceschini, Nora; Curb, J. David; Martin, Lisa W.; Eaton, Charles B.; Kardia, Sharon L. R.; Taylor, Herman A.; Caulfield, Mark J.; Ehret, Georg B.; Johnson, Toby; Chakravarti, Aravinda; Zhu, Xiaofeng; Levy, Daniel

    2011-01-01

    The prevalence of hypertension in African Americans (AAs) is higher than in other US groups; yet, few have performed genome-wide association studies (GWASs) in AA. Among people of European descent, GWASs have identified genetic variants at 13 loci that are associated with blood pressure. It is unkno

  9. Meta-analysis of the comparative effects of different classes of antihypertensive agents on brachial and central systolic blood pressure, and augmentation index.

    Science.gov (United States)

    Manisty, Charlotte H; Hughes, Alun D

    2013-01-01

    Brachial systolic blood pressure (bSBP) exceeds aortic pressure by a variable amount, and estimated central systolic blood pressure (cSBP) may be a better indicator of cardiovascular risk than bSBP. We undertook a systematic review and meta-analysis to compare the effect of single and multiple antihypertensive agents on bSBP, cSBP and augmentation index (AIx). A random effects meta-analysis was performed on 24 randomized controlled trials of antihypertensives with measurements of bSBP, cSBP and/or AIx. Separate analyses were performed for drug comparisons with or without placebo, and drug combinations. In the placebo vs. drug meta-analysis, antihypertensive therapy reduced bSBP more than cSBP and there was no statistically significant evidence of heterogeneity by drug class, although the number of individual studies was small. In placebo-adjusted drug vs. drug comparison, treatment with β-blockers, omapatrilat and thiazide diuretics lowered cSBP significantly less than bSBP (i.e. central to brachial amplification decreased), whereas other monotherapies lowered cSBP and bSBP to similar extents. Sample sizes were too small and effect estimates insufficiently precise to allow firm conclusions to be made regarding comparisons between individual drug classes. Antihypertensive combinations that included β-blockers decreased central to brachial amplification. β-Blockers increased AIx, whereas all other antihypertensive agents reduced AIx to similar extents. A reduction in central to brachial amplification by some classes of antihypertensive drug will result in lesser reductions in cSBP despite achievement of target bSBP. This effect could contribute to differences in outcomes in randomized clinical trials when β-blocker- and/or diuretic-based antihypertensive therapy are compared with other regimens. © 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.

  10. Prognostic value of the increase in systolic blood pressure with exercise in patients with hypertension and known or suspected coronary artery disease.

    Science.gov (United States)

    Bouzas-Mosquera, Carmen; Bouzas-Mosquera, Alberto; Peteiro, Jesús

    2017-01-20

    The association of an exaggerated systolic blood pressure increase with exercise (EBPIE) with cardiovascular events remains controversial. Our aim was to determine the possible association of an EBPIE with survival and risk of serious cardiac events in patients with hypertension and known or suspected coronary artery disease (CAD). This is a retrospective observational study based on a sample of 5226 patients with a history of arterial hypertension and known or suspected CAD referred for exercise echocardiography. The EBPIE was defined as an increase in systolic blood pressure with exercise greater than or equal to the 95th percentile of this population (80mmHg). The end points were all-cause mortality, cardiac death and myocardial infarction (MI). During a mean follow-up of 4.7 years, there were 978 deaths (including 371 cardiac) and 798 MI. Annual rates of all-cause mortality, cardiac mortality and MI were 2.73, 0.83 and 2.63% in patients with EBPIE and 4.4, 1.58 and 3.98% in those without EBPIE (P<.001, P=.012, and P=.014, respectively). After multivariate analysis, an EBPIE remained independently associated with a lower risk of all-cause mortality (HR: 0.70, 95% CI: 0.52-0.95; P=.023) and MI (HR: 0.69, 95% CI: 0.50-0.95; P=.022) but was not significantly associated with cardiac mortality (HR: 0.72, 95% CI: 0.43-1.20; P=.2). EBPIE was associated with an increased likelihood of survival and lower rate of MI in hypertensive patients with known or suspected CAD. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  11. Heart Rate and Systolic Blood Pressure Variability in the Time Domain in Patients with Recent and Long-Standing Diabetes Mellitus.

    Directory of Open Access Journals (Sweden)

    Ana Leonor Rivera

    Full Text Available Diabetes Mellitus (DM affects the cardiovascular response of patients. To study this effect, interbeat intervals (IBI and beat-to-beat systolic blood pressure (SBP variability of patients during supine, standing and controlled breathing tests were analyzed in the time domain. Simultaneous noninvasive measurements of IBI and SBP for 30 recently diagnosed and 15 long-standing DM patients were compared with the results for 30 rigorously screened healthy subjects (control. A statistically significant distinction between control and diabetic subjects was provided by the standard deviation and the higher moments of the distributions (skewness, and kurtosis with respect to the median. To compare IBI and SBP for different populations, we define a parameter, α, that combines the variability of the heart rate and the blood pressure, as the ratio of the radius of the moments for IBI and the same radius for SBP. As diabetes evolves, α decreases, standard deviation of the IBI detrended signal diminishes (heart rate signal becomes more "rigid", skewness with respect to the median approaches zero (signal fluctuations gain symmetry, and kurtosis increases (fluctuations concentrate around the median. Diabetes produces not only a rigid heart rate, but also increases symmetry and has leptokurtic distributions. SBP time series exhibit the most variable behavior for recently diagnosed DM with platykurtic distributions. Under controlled breathing, SBP has symmetric distributions for DM patients, while control subjects have non-zero skewness. This may be due to a progressive decrease of parasympathetic and sympathetic activity to the heart and blood vessels as diabetes evolves.

  12. Effect of eprosartan-based therapy on systolic blood pressure and total cardiovascular risk in a large international population: preliminary report of the observational POWER study.

    Science.gov (United States)

    Goudev, Assen; Berrou, Jean-Pascal; Pathak, Atul

    2012-01-01

    Estimation of total cardiovascular risk is useful for developing preventive strategies for individual patients. The POWER (Physicians' Observational Work on Patient Education According to their Vascular Risk) survey, a 6-month, open-label, multinational, post-marketing observational evaluation of eprosartan, an angiotensin II receptor blocker, was undertaken to assess the efficacy and safety of eprosartan-based therapy in the treatment of high arterial blood pressure in a large population recruited from 16 countries with varying degrees of baseline cardiovascular risk, and the effect of eprosartan-based therapy on total cardiovascular risk, as represented by the SCORE (Systematic Coronary Risk Assessment) or Framingham risk equations. Participating physicians recruited > 29,000 hypertensive patients whom they considered to be candidates (according to specified criteria) for treatment with eprosartan 600 mg/day, with other drugs added at the discretion of the physician. During treatment, systolic blood pressure decreased by 25.8 ± 14.4 mmHg to 134.6 ± 11.4 mmHg (P blood pressure fell by 12.6 ± 9.5 mmHg to 81.1 ± 7.6 mmHg, and pulse pressure fell by 13.2 ± 13.5 mmHg to 53.6 ± 11.4 mmHg (both P risk declined in parallel with the reduction in blood pressure. The POWER study has demonstrated, in a large and nonselected population, the feasibility and practicability of reducing total cardiovascular risk through systematic management of high blood pressure.

  13. Comparing systolic and diastolic Blood pressure changes and heartbeat rate following administration of anesthetics containing epinephrine and felypressin

    Directory of Open Access Journals (Sweden)

    M. Jafari

    1998-05-01

    Full Text Available   Complex mechanisms have been known for keeping blood pressure in normal level. In fact, these mechanisms have inter-related functions and can be dysregulated by both internal and external stimuli while cardiovascular system functions to minimize these changes. Vasoconstrictors can cause clinical and hemodynamical changes as 1-2 cartridges of epinephrine containing lidocaine can has no considerable effects in a normal individual ( unless administered IV but 3 cartridges can bring about some clinical symptoms, according to a number of investigations. In current study, epinephrine’s effect on heartbeat rate was found more potent than felypressin which is considered as a disadvantage. on the other hand, epinephrine acts on arteries and can cause less bleeding, less drug toxicity and deeper and longer anesthesia. Therefore, it is preferred to felypressin due to its better action. It should be noted that the changes resulted by epinephrine and felypressin are of no significant importance in healthy individuals.

  14. 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.

  15. Associated risk factors for silent cerebral infarcts in sickle cell anemia: low baseline hemoglobin, sex, and relative high systolic blood pressure.

    Science.gov (United States)

    DeBaun, Michael R; Sarnaik, Sharada A; Rodeghier, Mark J; Minniti, Caterina P; Howard, Thomas H; Iyer, Rathi V; Inusa, Baba; Telfer, Paul T; Kirby-Allen, Melanie; Quinn, Charles T; Bernaudin, Françoise; Airewele, Gladstone; Woods, Gerald M; Panepinto, Julie Ann; Fuh, Beng; Kwiatkowski, Janet K; King, Allison A; Rhodes, Melissa M; Thompson, Alexis A; Heiny, Mark E; Redding-Lallinger, Rupa C; Kirkham, Fenella J; Sabio, Hernan; Gonzalez, Corina E; Saccente, Suzanne L; Kalinyak, Karen A; Strouse, John J; Fixler, Jason M; Gordon, Mae O; Miller, J Phillip; Noetzel, Michael J; Ichord, Rebecca N; Casella, James F

    2012-04-19

    The most common form of neurologic injury in sickle cell anemia (SCA) is silent cerebral infarction (SCI). In the Silent Cerebral Infarct Multi-Center Clinical Trial, we sought to identify risk factors associated with SCI. In this cross-sectional study, we evaluated the clinical history and baseline laboratory values and performed magnetic resonance imaging of the brain in participants with SCA (HbSS or HbSβ° thalassemia) between the ages of 5 and 15 years with no history of overt stroke or seizures. Neuroradiology and neurology committees adjudicated the presence of SCI. SCIs were diagnosed in 30.8% (251 of 814) participants who completed all evaluations and had valid data on all prespecified demographic and clinical covariates. The mean age of the participants was 9.1 years, with 413 males (50.7%). In a multivariable logistic regression analysis, lower baseline hemoglobin concentration (P blood pressure (P = .018), and male sex (P = .030) were statistically significantly associated with an increased risk of an SCI. Hemoglobin concentration and systolic blood pressure are risk factors for SCI in children with SCA and may be therapeutic targets for decreasing the risk of SCI. This study is registered at www.clinicaltrials.gov as #NCT00072761.

  16. Association of the D8S282 marker near the lipoprotein lipase gene locus with systolic blood pressure in healthy Chinese subjects.

    Science.gov (United States)

    Ma, Yan-Qing; Thomas, G Neil; Critchley, Julian A J H; Lee, Zoe S K; Chan, Juliana C N; Tomlinson, Brian

    2002-11-01

    To investigate the association between the marker D8S282 near the lipoprotein lipase (LPL) gene locus, and blood pressure, anthropometric and biochemical parameters in 229 healthy Chinese subjects. METHOD Genotyping was performed using an automated DNA sequencer and the Base ImageIR software. Eight different alleles were identified (272-286 bp) resulting in 15 genotypes in our population. We investigated the association between the common (28.8%) 278 bp allele and the anthropometric and biochemical parameters. In a tertile analysis, the frequency of the 278 bp allele increased linearly ( P = 0.003) with increasing systolic blood pressure (SBP). The relationship was most evident in the females ( n = 141); SBP was higher in homozygotes for the 278 bp allele (117 +/- 10 mmHg, = 12) than those without this allele (109 +/- 9 mmHg, = 77, 0.05) and was gene-dose dependent, and this difference was more significant after adjusting for age (P = 0.004). No relationship between the locus and the anthropometric or biochemical parameters investigated was observed. The D8S282 marker near the LPL gene locus contributes to the variance of SBP in healthy Hong Kong Chinese subjects, particularly in females.

  17. Influence of pretreatment systolic blood pressure on the effect of carvedilol in patients with severe chronic heart failure: the Carvedilol Prospective Randomized Cumulative Survival (COPERNICUS) study.

    Science.gov (United States)

    Rouleau, Jean L; Roecker, Ellen B; Tendera, Michal; Mohacsi, Paul; Krum, Henry; Katus, Hugo A; Fowler, Michael B; Coats, Andrew J S; Castaigne, Alain; Scherhag, Armin; Holcslaw, Terry L; Packer, Milton

    2004-04-21

    We sought to evaluate the influence of pretreatment systolic blood pressure (SBP) on the efficacy and safety of carvedilol in patients with chronic heart failure (CHF). Although beta-blockers reduce the risk of death in CHF, there is little reported experience with these drugs in patients with a low pretreatment SBP, who may respond poorly to beta-blockade. We studied 2,289 patients with severe CHF who participated in the Carvedilol Prospective Randomized Cumulative Survival (COPERNICUS) trial. Compared with placebo, carvedilol improved the clinical status and reduced the risk of death and the combined risk of death or hospitalization for any reason, for a cardiovascular reason, or for worsening heart failure (p 0.10). However, because patients with the lowest SBP were at highest risk of an event, they experienced the greatest absolute benefit from treatment with carvedilol. The lower the pretreatment SBP, the more likely that patients would report an adverse event, be intolerant of high doses of the study drug, or require permanent withdrawal of treatment (p < 0.001 for all). However, these risks were primarily related to the severity of the underlying illness and not to treatment with carvedilol. The current study provides little support for concerns about using beta-blockers (particularly those with vasodilatory actions) in patients with severe CHF who have a low SBP. Pretreatment blood pressure can identify patients who have the greatest need for risk reduction with carvedilol.

  18. Development and validation of optimal cut-off value in inter-arm systolic blood pressure difference for prediction of cardiovascular events.

    Science.gov (United States)

    Hirono, Akira; Kusunose, Kenya; Kageyama, Norihito; Sumitomo, Masayuki; Abe, Masahiro; Fujinaga, Hiroyuki; Sata, Masataka

    2017-08-19

    An inter-arm systolic blood pressure difference (IAD) is associated with cardiovascular disease. The aim of this study was to develop and validate the optimal cut-off value of IAD as a predictor of major adverse cardiac events in patients with arteriosclerosis risk factors. From 2009 to 2014, 1076 patients who had at least one cardiovascular risk factor were included in the analysis. We defined 700 randomly selected patients as a development cohort to confirm that IAD was the predictor of cardiovascular events and to determine optimal cut-off value of IAD. Next, we validated outcomes in the remaining 376 patients as a validation cohort. The blood pressure (BP) of both arms measurements were done simultaneously using the ankle-brachial blood pressure index (ABI) form of automatic device. The primary endpoint was the cardiovascular event and secondary endpoint was the all-cause mortality. During a median period of 2.8 years, 143 patients reached the primary endpoint in the development cohort. In the multivariate Cox proportional hazards analysis, IAD was the strong predictor of cardiovascular events (hazard ratio: 1.03, 95% confidence interval: 1.01-1.05, p=0.005). The receiver operating characteristic curve revealed that 5mmHg was the optimal cut-off point of IAD to predict cardiovascular events (p<0.001). In the validation cohort, the presence of a large IAD (IAD ≥5mmHg) was significantly associated with the primary endpoint (p=0.021). IAD is significantly associated with future cardiovascular events in patients with arteriosclerosis risk factors. The optimal cut-off value of IAD is 5mmHg. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  19. Cocoa extract intake for 4 weeks reduces postprandial systolic blood pressure response of obese subjects, even after following an energy-restricted diet

    Directory of Open Access Journals (Sweden)

    Idoia Ibero-Baraibar

    2016-03-01

    Full Text Available Background: Cardiometabolic profile is usually altered in obesity. Interestingly, the consumption of flavanol-rich foods might be protective against those metabolic alterations. Objective: To evaluate the postprandial cardiometabolic effects after the acute consumption of cocoa extract before and after 4 weeks of its daily intake. Furthermore, the bioavailability of cocoa extract was investigated. Design: Twenty-four overweight/obese middle-aged subjects participated in a 4-week intervention study. Half of the volunteers consumed a test meal enriched with 1.4 g of cocoa extract (415 mg flavanols, while the rest of the volunteers consumed the same meal without the cocoa extract (control group. Glucose and lipid profile, as well as blood pressure and cocoa metabolites in plasma, were assessed before and at 60, 120, and 180 min post-consumption, at the beginning of the study (Postprandial 1 and after following a 4-week 15% energy-restricted diet including meals containing or not containing the cocoa extract (Postprandial 2. Results: In the Postprandial 1 test, the area under the curve (AUC of systolic blood pressure (SBP was significantly higher in the cocoa group compared with the control group (p=0.007, showing significant differences after 120 min of intake. However, no differences between groups were observed at Postprandial 2. Interestingly, the reduction of postprandial AUC of SBP (AUC_Postprandial 2-AUC_Postprandial 1 was higher in the cocoa group (p=0.016. Furthermore, cocoa-derived metabolites were detected in plasma of the cocoa group, while the absence or significantly lower amounts of metabolites were found in the control group. Conclusions: The daily consumption of cocoa extract within an energy-restricted diet for 4 weeks resulted in a greater reduction of postprandial AUC of SBP compared with the effect of energy-restricted diet alone and independently of body weight loss. These results suggest the role of cocoa flavanols on

  20. Heart Rate and Systolic Blood Pressure Variability in the Time Domain in Patients with Recent and Long-Standing Diabetes Mellitus

    Science.gov (United States)

    Rivera, Ana Leonor; Estañol, Bruno; Sentíes-Madrid, Horacio; Fossion, Ruben; Toledo-Roy, Juan C.; Mendoza-Temis, Joel; Morales, Irving O.; Landa, Emmanuel; Robles-Cabrera, Adriana; Moreno, Rene; Frank, Alejandro

    2016-01-01

    Diabetes Mellitus (DM) affects the cardiovascular response of patients. To study this effect, interbeat intervals (IBI) and beat-to-beat systolic blood pressure (SBP) variability of patients during supine, standing and controlled breathing tests were analyzed in the time domain. Simultaneous noninvasive measurements of IBI and SBP for 30 recently diagnosed and 15 long-standing DM patients were compared with the results for 30 rigorously screened healthy subjects (control). A statistically significant distinction between control and diabetic subjects was provided by the standard deviation and the higher moments of the distributions (skewness, and kurtosis) with respect to the median. To compare IBI and SBP for different populations, we define a parameter, α, that combines the variability of the heart rate and the blood pressure, as the ratio of the radius of the moments for IBI and the same radius for SBP. As diabetes evolves, α decreases, standard deviation of the IBI detrended signal diminishes (heart rate signal becomes more “rigid”), skewness with respect to the median approaches zero (signal fluctuations gain symmetry), and kurtosis increases (fluctuations concentrate around the median). Diabetes produces not only a rigid heart rate, but also increases symmetry and has leptokurtic distributions. SBP time series exhibit the most variable behavior for recently diagnosed DM with platykurtic distributions. Under controlled breathing, SBP has symmetric distributions for DM patients, while control subjects have non-zero skewness. This may be due to a progressive decrease of parasympathetic and sympathetic activity to the heart and blood vessels as diabetes evolves. PMID:26849653

  1. Elevated systolic blood pressure of children in the United States is associated with low serum 25-hydroxyvitamin D concentrations related to body mass index: National Health and Examination Survey 2007-2010.

    Science.gov (United States)

    Moore, Carolyn E; Liu, Yan

    2017-02-01

    A negative association between serum 25-hydroxyvitamn D (25[OH]D) concentrations and blood pressure has been found in adults; whether a similar relationship exists in children remains unclear. We hypothesized that serum 25(OH)D concentrations of children would negatively correlate with blood pressure. Using a nationally representative sample of children aged 8 to 18years from the National Health and Nutrition Examination Survey 2007-2010 (n=2908), we compared serum 25(OH)D levels with diastolic and systolic blood pressure by vitamin D nutritional status categories. A high percentage of children were either vitamin D deficient (28.8%) or vitamin D insufficient (48.8%). Prehypertension was defined as blood pressure as ≥90th to blood pressure percentile norms for children. Vitamin D-deficient children aged 8 to 13years had higher systolic blood pressure (104.8±0.7mm Hg) than did vitamin D-sufficient children (102.3±0.6mmHg; Pblood pressure was inversely associated with serum 25(OH)D concentrations (Plow serum 25(OH)D concentrations with elevated systolic blood pressure in children is likely related to body weight and markers of adiposity. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Effect of eprosartan-based therapy on systolic blood pressure and total cardiovascular risk in a large international population: preliminary report of the observational POWER study

    Directory of Open Access Journals (Sweden)

    Goudev A

    2012-09-01

    Full Text Available Assen Goudev,1 Jean-Pascal Berrou,2 Atul Pathak3 On behalf of the POWER Investigators1Department of Cardiology, Queen Giovanna University Hospital, Sofia, Bulgaria; 2Strategic Medical Affairs, CardioMetabolic Established Products, Abbott Products Operations AG, Allschwil, Switzerland; 3Faculte´ de Médecine et CHU Toulouse, Unité de Pharmacologie Cardiovasculaire et Autonome, Service de Pharmacologie et Cardiologie, INSERM U 1048, Université Paul Sabatier, Toulouse, FranceBackground: Estimation of total cardiovascular risk is useful for developing preventive strategies for individual patients. The POWER (Physicians' Observational Work on Patient Education According to their Vascular Risk survey, a 6-month, open-label, multinational, post-marketing observational evaluation of eprosartan, an angiotensin II receptor blocker, was undertaken to assess the efficacy and safety of eprosartan-based therapy in the treatment of high arterial blood pressure in a large population recruited from 16 countries with varying degrees of baseline cardiovascular risk, and the effect of eprosartan-based therapy on total cardiovascular risk, as represented by the SCORE® (Systematic Coronary Risk Assessment or Framingham risk equations.Methods: Participating physicians recruited > 29,000 hypertensive patients whom they considered to be candidates (according to specified criteria for treatment with eprosartan 600 mg/day, with other drugs added at the discretion of the physician.Results: During treatment, systolic blood pressure decreased by 25.8 ± 14.4 mmHg to 134.6 ± 11.4 mmHg (P < 0.001, mean diastolic blood pressure fell by 12.6 ± 9.5 mmHg to 81.1 ± 7.6 mmHg, and pulse pressure fell by 13.2 ± 13.5 mmHg to 53.6 ± 11.4 mmHg (both P < 0.01. Calculated total cardiovascular risk declined in parallel with the reduction in blood pressure.Conclusion: The POWER study has demonstrated, in a large and nonselected population, the feasibility and practicability of

  3. Impact of Stimulant Medication Use on Heart Rate and Systolic Blood Pressure During Submaximal Exercise Treadmill Testing in Adolescents.

    Science.gov (United States)

    Westover, Arthur N; Nakonezny, Paul A; Adinoff, Bryon; Brown, Edson Sherwood; Halm, Ethan A

    2016-12-01

    Inappropriately decreased heart rate (HR) during peak exercise and delayed heart rate recovery (HRR) has been observed in adult users of stimulant medications who underwent exercise testing, suggesting autonomic adaptation to chronic stimulant exposure. In the general population, this pattern of hemodynamic changes is associated with increased mortality risk. Whether the same pattern of hemodynamic changes might be observed in adolescent stimulant medication users undergoing exercise testing is unknown. Among adolescents (aged 12 to 20 years) that underwent submaximal exercise treadmill testing from 1999 to 2004 in the National Health and Nutrition Examination Survey, propensity score matching of stimulant medication users (n = 89) to matched nonusers (n = 267) was conducted. Testing consisted of a 3-minute warm-up period, two 3-minute exercise stages, and three 1-minute recovery periods, with the goal of reaching 75% of the predicted HR maximum. A linear mixed model analysis was used to evaluate the effect of stimulant exposure on each of the exercise outcomes. Stimulant medication users compared to matched nonusers had a lower peak HR in Stage 2 (154.9 vs. 158.3 beats/minute [bpm], p = 0.055) and lower HR at 1-minute recovery (142.2 vs. 146.4 bpm, p = 0.030). However, submaximal HRR at 1 minute did not differ between stimulant users and matched nonusers (13.0 vs. 12.1 bpm, p = 0.38). Duration of stimulant use was not related to these outcomes. Adolescent stimulant medication users compared to matched nonusers demonstrated a trend toward decreased HR during submaximal exercise, which is potential evidence of chronic adaptation with stimulant exposure. There was no evidence for delayed HRR in this study, and thus, no evidence for decreased parasympathetic activity during initial exercise recovery. Exercise testing outcomes may have utility in future research as a method to assess stimulant-associated autonomic nervous system adaptations.

  4. Submaximal Exercise Systolic Blood Pressure and Heart Rate at 20 Years of Follow-up: Correlates in the Framingham Heart Study.

    Science.gov (United States)

    Spartano, Nicole L; Lyass, Asya; Larson, Martin G; Lewis, Gregory D; Vasan, Ramachandran S

    2016-05-27

    Beyond their resting values, exercise responses in blood pressure (BP) and heart rate (HR) may add prognostic information for cardiovascular disease (CVD). In cross-sectional studies, exercise BP and HR responses correlate with CVD risk factors; however, it is unclear which factors influence longitudinal changes in exercise responses over time, which is important for our understanding of the development of CVD. We assessed BP and HR responses to low-level exercise tests (6-minute Bruce protocol) in 1231 Framingham Offspring participants (55% women) who underwent a routine treadmill test in 1979-1983 (baseline; mean age 39±8 years) that was repeated in 1998-2001 (follow-up; mean age 58±8 years). Adjusting for baseline exercise responses, we related the follow-up exercise responses to baseline CVD risk factors and to their changes between examinations. Compared with men, women had greater rise in exercise systolic (S)BP and HR at 20-year follow-up (both Pblood lipid levels, resting SBP and HR, and smoking status were associated with greater exercise SBP at follow-up (all Pexercise SBP and HR at follow-up (both Pexercise SBP (≥180 mm Hg) at follow-up (Pexercise in midlife. Maintaining or adopting a healthy risk factor profile may favorably impact the exercise responses over time. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  5. Familial resemblance on the Thurstone Activity Scale, systolic blood pressure, and total cholesterol among first degree relatives of subjects with and without coronary heart disease.

    Science.gov (United States)

    Carmelli, D; Rosenman, R

    1985-01-01

    An investigation of the pattern of familial resemblance of three different risk factors assessed in families of coronary heart disease (CHD) patients and controls is presented. The fathers of these families participated in the Western Collaborative Group Study that first established the type A/B behavior pattern as an independent risk factor for CHD. A recently developed methodology, the Structured Exploratory Data Analysis (SEDA), was implemented to examine parental interaction, parent-offspring closeness, asymmetries in transmission, and other differences in the pattern of familial similarities among family members of case and control subjects. The analysis performed revealed pronounced parent-child similarity for total serum cholesterol values in both case and control families; spouse closeness and parent-child resemblance for systolic blood pressure measurements only in control families; and sex asymmetries in the parent-child closeness on pace of activity, which also differed between case and control families. The results of this investigation underscore the value of examining the joint pattern of familial resemblance of a number of risk factors as a means for differentiating between cultural and biological factors affecting familial aggregation of CHD.

  6. Impact of an Early Decrease in Systolic Blood Pressure on The Risk of Contrast-Induced Nephropathy after Percutaneous Coronary Intervention.

    Science.gov (United States)

    Li, Hualong; Huang, Shuijin; He, Yiting; Liu, Yong; Liu, Yuanhui; Chen, Jiyan; Zhou, Yingling; Tan, Ning; Duan, Chongyang; Chen, Pingyan

    2016-02-01

    The early postprocedural period was thought to be the rush hour of contrast media excretion, causing rapid and prolonged renal hypoperfusion, which was the critical time window for contrast-induced nephropathy (CIN). 349 consecutive patients were enrolled into the study. The relation between an early postprocedural decrease in systolic blood pressure (SBP) and the risk of CIN was assessed using multivariate logistic regression. A postprocedural decrease in SBP was observed in 63% of patients and CIN developed in 28 (8.0%) patients. The CIN group had a lower postprocedural SBP (114.5±13.5 vs. 123.7±15.6mmHg, P=0.003) and a greater postprocedural decrease in SBP (16.2±19.1 vs. 5.9±18.7mmHg, P=0.005) than the no-CIN group. ROC analysis revealed that the optimum cutoff value for the SBP decrease in detecting CIN was >10mmHg (sensitivity 60.7%, specificity 59.5%, AUC=0.66). Multivariate logistic regression analysis found that a postprocedural decrease in SBP >10mmHg was a significant independent predictor of CIN (OR 2.368, 95%CI: 1.043-5.379, P=0.039), after adjustment for other risk factors. An early moderate postprocedural decrease in SBP may increase the risk of CIN in patients undergoing PCI. Copyright © 2015. Published by Elsevier B.V.

  7. Combining heart rate and systolic blood pressure to improve risk stratification in older patients with heart failure: Findings from the RICA Registry.

    Science.gov (United States)

    Sánchez-Gil, Justo; Manzano, Luis; Flather, Marcus; Formiga, Francesc; Martel, Alicia Conde; Molinero, Alberto Muela; López, Raul Quirós; Jiménez, Jose Luis Arias; Iborra, Pau Llácer; Perez-Calvo, Juan Ignacio; Montero-Pérez-Barquero, Manuel

    2017-03-01

    Heart rate (HR) and systolic blood pressure (SBP) are independent prognostic variables in patients with heart failure (HF). We evaluated if combining HR and SBP could improve prognostic assessment in older patients. Variables associated with all-cause mortality and readmission for HF during 9months of follow-up were analyzed from the Spanish Heart Failure Registry (RICA). HR and SBP values were stratified in three combined groups. We evaluated 1551 patients, 82years and 56% women. Using HR strata of rates of 9.8 and 13.6%, respectively (hazard ratio 1.0 and 1.35). For SBP≥140, 120-140 and rates were 8.2, 10.4 and 20.3%. respectively (hazard ratio 1.0, 1.34 and 2.76). Using combined strata of HRrates of 4.5%, 11.0% and 24.0%, respectively. Multivariate Cox regression for all-cause mortality shows for low-, middle- and high-risk groups was 1 (reference), 1.93 (95% CI: 0.93-3.99, p=0.077) and 4.32 (95% CI: 2.04-9.14, p<0.001). BMI, NYHA, MDRD, hypertension and sodium were also independent prognostic factors. The combination provides better risk discrimination than use of HR and SBP alone and may provide a simple and reliable tool for risk assessment for older HF patients in clinical practice. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Evaluation of the effect of systolic blood pressure and pulse pressure on cognitive function: the Women's Health and Aging Study II.

    Directory of Open Access Journals (Sweden)

    Sevil Yasar

    Full Text Available BACKGROUND: Evidence suggests that elevated systolic blood pressure (SBP and pulse pressure (PP in midlife is associated with increased risk for cognitive impairment later in life. There is mixed evidence regarding the effects of late life elevated SBP or PP on cognitive function, and limited information on the role of female gender. METHODS/PRINCIPAL FINDINGS: Effects of SBPand PPon cognitive abilities at baseline and over a 9-year period were evaluated in 337 non-demented community-dwelling female participants over age 70 in the Women's Health and Aging Study II using logistic and Cox proportional hazards regression analyses. Participants aged 76-80 years with SBP≥160 mmHg or PP≥84 mmHg showed increased incidence of impairment on Trail Making Test-Part B (TMT, Part B, a measure of executive function, over time when compared to the control group that included participants with normal and pre-hypertensive SBP (<120 and 120-139 mmHg or participants with low PP (<68 mmHg (HR = 5.05 [95%CI = 1.42, 18.04], [HR = 5.12 [95%CI = 1.11; 23.62], respectively. Participants aged 70-75 years with PP≥71 mmHg had at least a two-fold higher incidence of impairment on HVLT-I, a measure of verbal learning, over time when compared to participants with low PP (<68 mmHg (HR = 2.44 [95%CI = 1.11, 5.39]. CONCLUSIONS/SIGNIFICANCE: Our data suggest that elevated SBP or PP in older non-demented women increases risk for late-life cognitive impairment and that PP could be used when assessing the risk for impairment in cognitive abilities. These results warrant further, larger studies to evaluate possible effects of elevated blood pressure in normal cognitive aging.

  9. Association of early systolic blood pressure response to exercise with future cardiovascular events in patients with uncomplicated mild-to-moderate hypertension.

    Science.gov (United States)

    Cho, Min Soo; Jang, Sun-Joo; Lee, Chang Hoon; Park, Chong-Hun

    2012-09-01

    The relationship between blood pressure (BP) response during exercise and future cardiovascular events remains unclear. We assessed the association between an increase in early systolic BP (SBP) during exercise tests and future cardiovascular events in patients with sustained hypertension (sHT). Between 2002 and 2005, we enrolled 300 patients newly diagnosed with mild-to-moderate sHT without complications from the Asan Ambulatory Blood Pressure Monitoring registry. All the patients successfully performed treadmill tests, achieving target heart rate according to the Naughton/Balke protocol. The patients were divided into quartiles according to their SBP at 8 min (7.4 metabolic equivalent tasks). The primary outcome was the composite of all-cause death, new-onset ischemic heart disease and stroke. The 5-year survival rates did not differ significantly among quartiles 1-4 (100% vs. 96.6% vs. 94.4% vs. 98.3%, P=0.211). Relative to quartile 1, the 5-year event-free survival rates were significantly lower in patients in quartiles 3 (86.9% vs. 98.3%, P=0.023) and 4 (88.2% vs. 98.3%, P=0.023). After multivariable adjustment for covariates, the risk for the composite end point was higher for patients in quartiles 3 (Hazard ratio (HR) 4.69, 95% confidence interval (CI) 1.28-17.13, P=0.020) and 4 (HR 3.65, 95% CI 0.92-14.50, P=0.065) than in quartiles 1 and 2. Cardiovascular risk was significantly higher in patients with stage 4 SBP (>180 mm Hg) even after adjustment (HR 4.00, 95% CI 1.19-13.44, P=0.025). Increased submaximal SBP response to exercise may be a predictor of future cardiovascular events in patients with mild-to-moderate sHT.

  10. Mineralocorticoid receptors, inflammation and sympathetic drive in a rat model of systolic heart failure.

    Science.gov (United States)

    Felder, Robert B

    2010-01-01

    Appreciation for the role of aldosterone and mineralocorticoid receptors in cardiovascular disease is accelerating rapidly. Recent experimental work has unveiled a strong relationship between brain mineralocorticoid receptors and sympathetic drive, an important determinant of outcome in heart failure and hypertension. Two putative mechanisms are explored in this manuscript. First, brain mineralocorticoid receptors may influence sympathetic discharge by regulating the release of pro-inflammatory cytokines into the circulation. Blood-borne pro-inflammatory cytokines act upon receptors in the microvasculature of the brain to induce cyclooxygenase-2 activity and the production of prostaglandin E(2), which penetrates the blood-brain barrier to activate the sympathetic nervous system. Second, brain mineralocorticoid receptors may influence sympathetic drive by upregulating the activity of the brain renin-angiotensin system, resulting in NAD(P)H oxidase-dependent superoxide production. A potential role for superoxide-dependent mitogen-activated protein kinase signalling pathways in the regulation of sympathetic nerve activity is also considered. Other potential downstream signalling mechanisms contributing to mineralocorticoid receptor-mediated sympathetic excitation are under investigation.

  11. Lower systolic blood pressure at age 7 y in low-birth-weight children who received iron supplements in infancy: results from a randomized controlled trial.

    Science.gov (United States)

    Lindberg, Josefine; Norman, Mikael; Westrup, Björn; Domellöf, Magnus; Berglund, Staffan K

    2017-08-01

    Background: Low birth weight (LBW) (≤2500 g) is associated with iron deficiency in infancy and high blood pressure (BP) later in life.Objective: We investigated the effect of iron supplementation that was given to LBW infants on midchildhood BP.Design: The study was a randomized, double-blind, controlled trial that included 285 marginally LBW (2000-2500-g) infants at 2 Swedish centers between May 2004 and November 2007. The infants were randomly assigned to receive a placebo or 1 or 2 mg Fe · kg(-1) · d(-1) from 6 wk to 6 mo of age. In secondary analyses at the age of 7 y, systolic blood pressure (SBP), diastolic blood pressure (DBP), and the prevalence of children with BP within the hypertensive range (>90th percentile) were compared between the groups.Results: BP was analyzed via intention to treat in 189 children (66%). The mean ± SD SBP was 103 ± 8.1, 101 ± 7.5, and 101 ± 7.8 mm Hg in children who had received the placebo (n = 70), 1 mg Fe · kg(-1) · d(-1) (n = 54), or 2 mg Fe · kg(-1) · d(-1) (n = 65), respectively. When the iron-supplemented groups were combined in covariate-adjusted analyses, the mean SBP in LBW children who had received iron supplementation in infancy was 2.2 mm Hg (95% CI: 0.3, 4.2 mm Hg) lower than in those who were unsupplemented (P = 0.026). Multivariate logistic regression showed that iron supplementation in infancy reduced the odds of having an SBP within the hypertensive range at 7 y of age (OR: 0.32; 95% CI: 0.11, 0.96). For DBP, there were no significant differences between the intervention groups.Conclusions: LBW children who receive iron supplementation (1 or 2 mg Fe · kg(-1) · d(-1)) in infancy have lower SBP at 7 y. This (to our knowledge) novel observation suggests that the increased risk of hypertension that is observed in children and adults who are born small might be reduced with early micronutrient interventions. This trial was registered at clinicaltrials.gov as NCT00558454. © 2017 American Society for

  12. Path modelling of antecedent of diabetes mellitus on blood glucose measurements

    Science.gov (United States)

    Latif, Humaira'Abdul; Hamid, Mohd Rashid Ab; Azizan, Nor Azlinna; Jemain, Abdul Aziz

    2017-05-01

    Diabetes Mellitus (DM) is one of the non-communicable diseases and public health problems facing the worldwide population that includes Malaysia. Hitherto, the prevalence of DM becomes worsening with an estimated of 3.4 million Malaysians are diabetes sufferers and expectedly increasing year by year. Thus, this study is of great importance by regressing the medical factors that affect the blood glucose level using structural equation modelling (SEM). The SEM with partial least squares (PLS) estimation was applied to a secondary data of 644 respondents, aged ≥ 18 years in Malaysia. The data were collected in 2011 by Ministry of Health Malaysia (MOH). The variables under study are blood glucose level, cholesterol level (CL), systolic blood pressure (SBP), diastolic blood pressure (DBP), waist circumference (WC) and body mass index (BMI). From the modelling analysis, it showed that the cholesterol level (CL), systolic blood pressure (SBP) and waist circumference (WC) showed a positive significant relationship p diabetes mellitus among adults.

  13. A relative difference in systolic blood pressure between arms by synchronal measurement and conventional cardiovascular risk factors are associated with the severity of coronary atherosclerosis.

    Science.gov (United States)

    Yamamoto, Tomohiko; Miura, Shin-Ichiro; Suematsu, Yasunori; Kuwano, Takashi; Sugihara, Makoto; Ike, Amane; Iwata, Atsushi; Nishikawa, Hiroaki; Saku, Keijiro

    2016-06-01

    It is not known the relationships between a difference in systolic blood pressure (SBP) or diastolic BP (DBP) between arms by synchronal measurement and the presence of coronary artery disease (CAD), and between a difference in BP between arms and the severity of coronary atherosclerosis. We enrolled 425 consecutive patients (M/F = 286/139, 67 ± 13 year) who were admitted to our University Hospital and in whom we could measure the absolute (|rt. BP - lt. BP|) and relative (rt. BP - lt. BP) differences in SBP and DBP using a nico PS-501(®) (Parama-Tech). We divided all patients into those who did and did not have CAD. The relative differences in SBP between arms in patients with CAD were significantly lower than those in patients without CAD. However, the relative difference in SBP between arms was not a predictor of the presence of CAD. We also divided 267 patients who underwent coronary angiography into tertiles according to the Gensini score (low, middle, and high score groups). Interestingly, the middle + high score groups showed significantly lower relative differences in SBP between arms than the low score group. The mean Korotkoff sound graph in the middle + high Gensini score group was significantly higher than that in the low Gensini score group. Among conventional cardiovascular risk factors and nico parameters, the relative difference in SBP between arms in addition to the risk factors (age, gender, body mass index, hypertension, dyslipidemia, and diabetes mellitus) was associated with the score by a logistic regression analysis. In conclusion, the relative difference in SBP between arms as well as conventional risk factors may be associated with the severity of coronary arteriosclerosis.

  14. Impact of age on the importance of systolic and diastolic blood pressures for stroke risk: the MOnica, Risk, Genetics, Archiving, and Monograph (MORGAM) Project.

    Science.gov (United States)

    Vishram, Julie K K; Borglykke, Anders; Andreasen, Anne H; Jeppesen, Jørgen; Ibsen, Hans; Jørgensen, Torben; Broda, Grazyna; Palmieri, Luigi; Giampaoli, Simona; Donfrancesco, Chiara; Kee, Frank; Mancia, Giuseppe; Cesana, Giancarlo; Kuulasmaa, Kari; Sans, Susana; Olsen, Michael H

    2012-11-01

    This study investigates age-related shifts in the relative importance of systolic (SBP) and diastolic (DBP) blood pressures as predictors of stroke and whether these relations are influenced by other cardiovascular risk factors. Using 34 European cohorts from the MOnica, Risk, Genetics, Archiving, and Monograph (MORGAM) Project with baseline between 1982 and 1997, 68 551 subjects aged 19 to 78 years, without cardiovascular disease and not receiving antihypertensive treatment, were included. During a mean of 13.2 years of follow-up, stroke incidence was 2.8%. Stroke risk was analyzed using hazard ratios per 10-mm Hg/5-mm Hg increase in SBP/DBP by multivariate-adjusted Cox regressions, including SBP and DBP simultaneously. Because of nonlinearity, DBP was analyzed separately for DBP ≥ 71 mm Hg and DBP <71 mm Hg. Stroke risk was associated positively with SBP and DBP ≥ 71 mm Hg (SBP/DBP ≥ 71 mm Hg; hazard ratios: 1.15/1.06 [95% CI: 1.12-1.18/1.03-1.09]) and negatively with DBP <71 mm Hg (0.88[0.79-0.98]). The hazard ratio for DBP decreased with age (P<0.001) and was not influenced by other cardiovascular risk factors. Taking into account the age × DBP interaction, both SBP and DBP ≥ 71 mm Hg were significantly associated with stroke risk until age 62 years, but in subjects older than 46 years the superiority of SBP for stroke risk exceeded that of DBP ≥ 71 mm Hg and remained significant until age 78 years. DBP <71 mm Hg became significant at age 50 years with an inverse relation to stroke risk. In Europeans, stroke risk should be assessed by both SBP and DBP until age 62 years with increased focus on SBP from age 47 years. From age 62 years, emphasis should be on SBP without neglecting the potential harm of very low DBP.

  15. An alternative approach to approximate entropy threshold value (r) selection: application to heart rate variability and systolic blood pressure variability under postural challenge.

    Science.gov (United States)

    Singh, A; Saini, B S; Singh, D

    2016-05-01

    This study presents an alternative approach to approximate entropy (ApEn) threshold value (r) selection. There are two limitations of traditional ApEn algorithm: (1) the occurrence of undefined conditional probability (CPu) where no template match is found and (2) use of a crisp tolerance (radius) threshold 'r'. To overcome these limitations, CPu is substituted with optimum bias setting ɛ opt which is found by varying ɛ from (1/N - m) to 1 in the increments of 0.05, where N is the length of the series and m is the embedding dimension. Furthermore, an alternative approach for selection of r based on binning the distance values obtained by template matching to calculate ApEnbin is presented. It is observed that ApEnmax, ApEnchon and ApEnbin converge for ɛ opt = 0.6 in 50 realizations (n = 50) of random number series of N = 300. Similar analysis suggests ɛ opt = 0.65 and ɛ opt = 0.45 for 50 realizations each of fractional Brownian motion and MIX(P) series (Lu et al. in J Clin Monit Comput 22(1):23-29, 2008). ɛ opt = 0.5 is suggested for heart rate variability (HRV) and systolic blood pressure variability (SBPV) signals obtained from 50 young healthy subjects under supine and upright position. It is observed that (1) ApEnbin of HRV is lower than SBPV, (2) ApEnbin of HRV increases from supine to upright due to vagal inhibition and (3) ApEnbin of BPV decreases from supine to upright due to sympathetic activation. Moreover, merit of ApEnbin is that it provides an alternative to the cumbersome ApEnmax procedure.

  16. Design, Implementation, and Test of a Multi-Model Systolic Neural-Network Accelerator

    Directory of Open Access Journals (Sweden)

    Thierry Cornu

    1996-01-01

    Full Text Available A multi-model neural-network computer has been designed and built. A compute-intensive application in the field of power-system monitoring, using the Kohonen neural network, has then been ported onto this machine. After a short description of the system, this article focuses on the programming paradigm adopted. The performance of the machine is also evaluated and discussed.

  17. A pilot study on the effects of magnesium supplementation with high and low habitual dietary magnesium intake on resting and recovery from aerobic and resistance exercise and systolic blood pressure.

    Science.gov (United States)

    Kass, Lindsy S; Skinner, Philip; Poeira, Filipe

    2013-01-01

    The effects of magnesium supplementation on blood pressure (BP) have been studied for over 25 years and results have been inconsistent. Blood pressure reductions in randomized studies have varied from 12 mmHg reductions to no reduction. The objective of this pilot intervention was to investigate the effect of magnesium supplementation on systolic blood pressure whilst resting and during recovery from aerobic and resistance exercise and on performance. A further objective was to see whether the effect of a high vs low habitual dietary magnesium intake affected these results. Sixteen male volunteers were randomly assigned to either a 300 mg·d(-1) magnesium oxide supplementation (MO) or a control group (CG) for 14 days. Resting blood pressure (BP) and heart rate (HR) were measured before subjects performed a maximal 30 minute cycle, immediately followed by three x 5 second isometric bench press, both at baseline and after the intervention. Blood pressure and heart rate were recorded immediately post exercise and after five minutes recovery. A 3 day food diary was recorded for all subjects to measure dietary magnesium intake. At the end of the intervention, the supplemented group, had a reduction in mean resting systolic BP by 8.9 mmHg (115.125 ± 9.46 mmHg, p = 0.01) and post exercise by 13 mmHg (122.625 ± 9. 88 mmHg, p = 0.01). Recovery BP was 11.9 mmHg lower in the intervention group compared to control (p = 0.006) and HR decreased by 7 beats per minute in the experimental group (69.0 ± 11.6 bpm, p = 0. 02). Performance indicators did not change within and between the groups. Habitual dietary magnesium intake affected both resting and post exercise systolic BP and the subsequent effect of the magnesium supplementation. These results have an implication in a health setting and for health and exercise but not performance. Key pointsMagnesium supplementation will have an effect on resting and recovery systolic blood pressure with aerobic exercise

  18. 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...

  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. All-cause mortality in patients with type 2 diabetes in association with achieved hemoglobin A(1c, systolic blood pressure, and low-density lipoprotein cholesterol levels.

    Directory of Open Access Journals (Sweden)

    Hou-Hsien Chiang

    Full Text Available BACKGROUND: To identify the ranges of hemoglobin A(1c (HbA1c, systolic blood pressure (SBP, and low-density lipoprotein cholesterol (LDL-C levels which are associated with the lowest all-cause mortality. METHODS: A retrospective cohort of 12,643 type 2 diabetic patients (aged ≥18 years were generated from 2002 to 2010, in Far-Eastern Memorial Hospital, New Taipei city, Taiwan. Patients were identified to include any outpatient diabetes diagnosis (ICD-9: 250, and drug prescriptions that included any oral hypoglycemic agents or insulin prescribed during the 6 months following their first outpatient visit for diabetes. HbA1c, SBP, and LDL-C levels were assessed by the mean value of all available data, from index date to death or censor date. Deaths were ascertained by matching patient records with the Taiwan National Register of Deaths. RESULTS: Our results showed general U-shaped associations, where the lowest hazard ratios occurred at HbA1c 7.0-8.0%, SBP 130-140 mmHg, and LDL-C 100-130 mg/dL. The risk of mortality gradually increases if the patient's mean HbA1c, SBP, or LDL-C during the follow-up period was higher or lower than these ranges. In comparison to the whole population, the adjusted hazard ratio (95% CI for patients with HbA1c 7.0-8.0%, SBP 130-140 mmHg, and LDL-C 100-130 mg/dL were 0.69 (0.62-0.77, 0.80 (0.72-0.90, and 0.68 (0.61-0.75, respectively. CONCLUSIONS: In our type 2 diabetic cohort, the patients with HbA1c 7.0-8.0%, SBP 130-140 mmHg, or LDL-C 100-130 mg/dL had the lowest all-cause mortality. Additional research is needed to confirm these associations and to further investigate their detailed mechanisms.

  1. Effect of antihypertensive agents on blood pressure variability: the Natrilix SR versus candesartan and amlodipine in the reduction of systolic blood pressure in hypertensive patients (X-CELLENT) study.

    Science.gov (United States)

    Zhang, Yi; Agnoletti, Davide; Safar, Michel E; Blacher, Jacques

    2011-08-01

    To investigate the effect of different antihypertensive agents on blood pressure (BP) variability (BPV) and the underlying mechanism, we analyzed the ambulatory BP monitoring data of 577 patients before and after 3-month antihypertensive treatment, in the Natrilix SR Versus Candesartan and Amlodipine in the Reduction of Systolic Blood Pressure in Hypertensive Patients (X-CELLENT) Study, a multicenter, multinational, randomized, double-blind, placebo-controlled study with 4 parallel treatment arms (placebo, candesartan, indapamide sustained release, and amlodipine). Within-subject mean and SD of 24-hour BP, weighted by time interval between consecutive readings, were calculated in 3 time frames (daytime, nighttime, and 24 hours) to evaluate BP and BPV. The mean 24-hour heart rate (HR) and HR variability were calculated with the same algorithms. We found that the 3 antihypertensive drugs had a similar BP-lowering effect (Ptreatment. On the other hand, the major determinants of BPV at baseline were age, mean BP, and the corresponding HR variability. However, the reduction in BPV by amlodipine was significantly associated with the reduction in BP (Ptreatment was associated with a significant reduction in BPV, and the mechanism of those reductions was possibly attributable to lowering BP or ameliorating the autonomic nervous system regulation or both. The combination of the 2 agents might help to optimize such properties.

  2. Systolic blood pressure variability and morning blood pressure surge in metabolic syndrome patients with high blood pressure%代谢综合征的高血压患者收缩压变异性及血压晨峰的研究

    Institute of Scientific and Technical Information of China (English)

    张雨; 许邦龙

    2016-01-01

    目的:探讨代谢综合征的高血压患者收缩压变异性、血压晨峰的临床特征,并分析其与代谢综合征的心血管危险因素之间的相关性。方法收集门诊高血压患者68例,分成合并有代谢综合征组(A 组,n =33)和单纯高血压组(B 组,n =35),对两组患者进行24 h 动态血压监测(ABPM),连续记录24 h、白天及夜间每半个小时收缩压数值,通过 SPSS 软件计算24 h、白天及夜间每半小时收缩压均值的标准差,即为24 h 收缩压变异性(24 h SBPV),白天收缩压变异性(白天 SBPV),夜间收缩压变异性(夜间 SBPV);计算起床后2 h 内收缩压平均值与夜间睡眠时的收缩压最低值(包括最低值在内的1 h 的平均值)的差值即为血压晨峰值。结果通过对 A、B 两组收缩压变异性、血压晨峰值进行对比分析,了解合并代谢综合征的高血压患者收缩压变异性、血压晨峰值与单纯高血压患者的区别。同时将代谢综合征定义中包括的多个心血管危险因素与24 h SBPV,白天 SBPV,夜间 SBPV 及血压晨峰值进行相关性分析,探讨与收缩压变异性、血压晨峰相关的影响因素。结论合并有代谢综合征的高血压患者血压变异性增加。%Objective To explore systolic blood pressure variability and the clinical characteristics of morning blood pressure surge in metabolic syndrome patients with high blood pressure,clinical features ,and to analyze the relationship between cardiovascular risk fac-tors and metabolic syndrome.Methods We collected 68 cases of hypertension treated in The Second Affiliated Hospital of Anhui Med-ical University from December 2013 to December 2015,which were assigned into two groups,metabolic syndrome combination group (group A,n =33)and simple hypertension group (group B,n =35).The two groups of patients received 24 hour ambulatory blood pressure monitoring (ABPM)and systolic blood

  3. Seven-year increase in exercise systolic blood pressure at moderate workload predicts long-term risk of coronary heart disease and mortality in healthy middle-aged men.

    Science.gov (United States)

    Skretteberg, Per Torger; Grundvold, Irene; Kjeldsen, Sverre E; Engeseth, Kristian; Liestøl, Knut; Erikssen, Gunnar; Erikssen, Jan; Gjesdal, Knut; Bodegard, Johan

    2013-05-01

    Exercise systolic blood pressure (SBP) predicts coronary heart disease (CHD) in the general population. We tested whether changes in exercise SBP during 7 years predict CHD (including angina pectoris, nonfatal myocardial infarction, and fatal CHD) and mortality over the following 28 years. Peak SBP at 100 W workload (=5.5 METS [metabolic equivalents]; completed by all participants) was measured among 1392 apparently healthy men in 1972-75 and repeated in 1979-82. The men were divided into quartiles (Q1-Q4) of exercise SBP change. Relative risks were calculated using Cox proportional hazard regression adjusting for family history of CHD, age, smoking status, resting SBP, peak SBP at 100 W, total cholesterol at first examination (model 1), and further for physical fitness and change in physical fitness (model 2). The highest quartile, Q4, was associated with a 1.55-fold (95% confidence interval, 1.17-2.03) adjusted (model 1) risk of CHD and a 1.93-fold (1.24-3.02) risk of coronary heart death compared with the lowest, Q1. Q4 had a 1.40-fold (1.06-1.85) risk of CHD and a 1.70-fold (1.08-2.68) risk of coronary heart death using model 2. Q4 was associated with increased risk of cardiovascular death and all-cause death compared with Q1 in model 1, but not in model 2. Our results indicate that an increase in exercise SBP at 100 W over 7 years is independently associated with increased long-term risk of CHD and substantiate our previous finding that high exercise SBP is an important risk factor for CHD in healthy men.

  4. In vivo adaptive response of the peripheral conduit artery in patients with borderline systolic hypertension

    Institute of Scientific and Technical Information of China (English)

    陶军; 靳亚非; 王礼春; 唐安丽; 廖新学; 杨震; 马虹

    2003-01-01

    Objective To investigate elastic changes of the radial artery, a medium-sized muscular peripheral conduit artery, in patients with borderline systolic hypertension. Methods Using a non-invasive high-resolution echo-tracking device coupled to a photoplethysmography (Finapres system) allowing simultaneous arterial diameter and finger blood pressure monitoring, we measured radial artery elastic parameters of 20 patients with borderline systolic hypertension and 20 normal subjects according to Langewouters model.Results The diameter of the radial artery of control subjects and those with borderline systolic hypertension at the isobaric level of 100 mmHg and mean arterial pressure was similar, but the compliance and distensibility at similar conditions in patients with borderline systolic hypertension did not further reduced and even increased. Conclusion In patients with borderline systolic hypertension, the adaptive responses of the radial artery compliance and distensibility to increased pressure were directed to maintain its elasticity, contributing to the homeostasis of the cardiovascular system.

  5. Effect of self-monitoring and medication self-titration on systolic blood pressure in hypertensive patients at high risk of cardiovascular disease: the TASMIN-SR randomized clinical trial.

    Science.gov (United States)

    McManus, Richard J; Mant, Jonathan; Haque, M Sayeed; Bray, Emma P; Bryan, Stirling; Greenfield, Sheila M; Jones, Miren I; Jowett, Sue; Little, Paul; Penaloza, Cristina; Schwartz, Claire; Shackleford, Helen; Shovelton, Claire; Varghese, Jinu; Williams, Bryan; Hobbs, F D Richard; Gooding, Trevor; Morrey, Ian; Fisher, Crispin; Buckley, David

    2014-08-27

    Self-monitoring of blood pressure with self-titration of antihypertensives (self-management) results in lower blood pressure in patients with hypertension, but there are no data about patients in high-risk groups. To determine the effect of self-monitoring with self-titration of antihypertensive medication compared with usual care on systolic blood pressure among patients with cardiovascular disease, diabetes, or chronic kidney disease. A primary care, unblinded, randomized clinical trial involving 552 patients who were aged at least 35 years with a history of stroke, coronary heart disease, diabetes, or chronic kidney disease and with baseline blood pressure of at least 130/80 mm Hg being treated at 59 UK primary care practices was conducted between March 2011 and January 2013. Self-monitoring of blood pressure combined with an individualized self-titration algorithm. During the study period, the office visit blood pressure measurement target was 130/80 mm Hg and the home measurement target was 120/75 mm Hg. Control patients received usual care consisting of seeing their health care clinician for routine blood pressure measurement and adjustment of medication if necessary. The primary outcome was the difference in systolic blood pressure between intervention and control groups at the 12-month office visit. Primary outcome data were available from 450 patients (81%). The mean baseline blood pressure was 143.1/80.5 mm Hg in the intervention group and 143.6/79.5 mm Hg in the control group. After 12 months, the mean blood pressure had decreased to 128.2/73.8 mm Hg in the intervention group and to 137.8/76.3 mm Hg in the control group, a difference of 9.2 mm Hg (95% CI, 5.7-12.7) in systolic and 3.4 mm Hg (95% CI, 1.8-5.0) in diastolic blood pressure following correction for baseline blood pressure. Multiple imputation for missing values gave similar results: the mean baseline was 143.5/80.2 mm Hg in the intervention group vs 144.2/79.9 mm Hg in the control group, and

  6. Systolic hypertension: an increasing clinical challenge in Asia

    Science.gov (United States)

    Park, Jeong Bae; Kario, Kazuomi; Wang, Ji-Guang

    2015-01-01

    Systolic hypertension, the predominant form of hypertension in patients aged over 50–60 years, is a growing health issue as the Asian population ages. Elevated systolic blood pressure is mainly caused by arterial stiffening, resulting from age-related vascular changes. Elevated systolic pressure increases the risk of cardiovascular disease, mortality and renal function decline, and this risk may increase at lower systolic pressure levels in Asian than Western subjects. Hence, effective systolic pressure lowering is particularly important in Asians yet blood pressure control remains inadequate despite the availability of numerous antihypertensive medications. Reasons for poor blood pressure control include low awareness of hypertension among health-care professionals and patients, under-treatment, and tolerability problems with antihypertensive drugs. Current antihypertensive treatments also lack effects on the underlying vascular pathology of systolic hypertension, so novel drugs that address the pathophysiology of arterial stiffening are needed for optimal management of systolic hypertension and its cardiovascular complications. PMID:25503845

  7. An adaptive technique for multiscale approximate entropy (MAEbin) threshold (r) selection: application to heart rate variability (HRV) and systolic blood pressure variability (SBPV) under postural stress.

    Science.gov (United States)

    Singh, Amritpal; Saini, Barjinder Singh; Singh, Dilbag

    2016-06-01

    Multiscale approximate entropy (MAE) is used to quantify the complexity of a time series as a function of time scale τ. Approximate entropy (ApEn) tolerance threshold selection 'r' is based on either: (1) arbitrary selection in the recommended range (0.1-0.25) times standard deviation of time series (2) or finding maximum ApEn (ApEnmax) i.e., the point where self-matches start to prevail over other matches and choosing the corresponding 'r' (rmax) as threshold (3) or computing rchon by empirically finding the relation between rmax, SD1/SD2 ratio and N using curve fitting, where, SD1 and SD2 are short-term and long-term variability of a time series respectively. None of these methods is gold standard for selection of 'r'. In our previous study [1], an adaptive procedure for selection of 'r' is proposed for approximate entropy (ApEn). In this paper, this is extended to multiple time scales using MAEbin and multiscale cross-MAEbin (XMAEbin). We applied this to simulations i.e. 50 realizations (n = 50) of random number series, fractional Brownian motion (fBm) and MIX (P) [1] series of data length of N = 300 and short term recordings of HRV and SBPV performed under postural stress from supine to standing. MAEbin and XMAEbin analysis was performed on laboratory recorded data of 50 healthy young subjects experiencing postural stress from supine to upright. The study showed that (i) ApEnbin of HRV is more than SBPV in supine position but is lower than SBPV in upright position (ii) ApEnbin of HRV decreases from supine i.e. 1.7324 ± 0.112 (mean ± SD) to upright 1.4916 ± 0.108 due to vagal inhibition (iii) ApEnbin of SBPV increases from supine i.e. 1.5535 ± 0.098 to upright i.e. 1.6241 ± 0.101 due sympathetic activation (iv) individual and cross complexities of RRi and systolic blood pressure (SBP) series depend on time scale under consideration (v) XMAEbin calculated using ApEnmax is correlated with cross-MAE calculated using ApEn (0.1-0.26) in steps of 0

  8. The evolution of systolic blood pressure as a strong predictor of cardiovascular risk and the effectiveness of fixed-dose ARB/CCB combinations in lowering levels of this preferential target

    Directory of Open Access Journals (Sweden)

    Jean-Jacques Mourad

    2008-12-01

    Full Text Available Jean-Jacques MouradHypertension Unit, Avicenne Hospital – AP-HP and Paris XIII University Bobigny, FranceAbstract: Elevated blood pressure is an important cardiovascular risk factor. Although targets for both diastolic blood pressure (DBP and systolic blood pressure (SBP are defined by current guidelines, DBP has historically taken precedence in hypertension management. However, there is strong evidence that SBP is superior to DBP as a predictor of cardiovascular events. Moreover, achieving control of SBP is assuming greater importance amongst an aging population. In spite of the growing recognition of the importance of SBP in reducing cardiovascular risk and the emphasis by current guidelines on SBP control, a substantial proportion of patients still fail to achieve SBP targets, and SBP control is achieved much less frequently than DBP control. Thus, new approaches to the management of hypertension are required in order to control SBP and minimize cardiovascular risk. Fixed-dose combination (FDC therapy is an approach that offers the advantages of multiple drug administration and a reduction in regimen complexity that favors compliance. We have reviewed the latest evidence demonstrating the efficacy in targeting SBP of the most recent FDC products; combinations of the calcium channel blocker (CCB, amlodipine, with angiotensin receptor blockers (ARBs, valsartan or olmesartan. In addition, results from studies with new classes of agent are outlined.Keywords: hypertension, systolic blood pressure, angiotensin receptor blocker, calcium channel blocker, combination therapy

  9. Influence of the Lactotripeptides Isoleucine-Proline-Proline and Valine-Proline-Proline on Systolic Blood Pressure in Japanese Subjects: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    Directory of Open Access Journals (Sweden)

    Aurelie Chanson-Rolle

    Full Text Available The lactotripeptides isoleucine-proline-proline (IPP and valine-proline-proline (VPP have been shown to decrease systolic blood pressure (SBP in several populations, but the size of the effect varies among studies. We performed a meta-analysis including all published studies to evaluate the SBP-lowering effect of IPP/VPP in Japanese subjects more comprehensively.Eligible randomized controlled trials were searched for within four bibliographic databases, including two Japanese ones. Eighteen studies (including a total of 1194 subjects were included in the meta-analysis. A random effect model using the restricted maximum likelihood (REML estimator was used for the analysis. The analysis showed that consumption of IPP/VPP induced a significant reduction in SBP as compared with placebo in Japanese subjects, with an estimated effect of -5.63 mm Hg (95% CI, -6.87 to -4.39, P<0.0001 and no evidence of publication bias. A significant heterogeneity between series was evident, which could be explained by a significant influence of the baseline blood pressure status of the subjects, the effect of IPP/VPP on SBP being stronger in hypertensive subjects (-8.35 mm Hg, P<0.0001 than in non-hypertensive subjects (-3.42mm Hg, P<0.0001. Furthermore, the effect of IPP/VPP on SBP remained significant when limiting the analysis to series that tested the usual doses of IPP/VPP consumed daily (below 5 mg/d, with estimated effects of -6.01 mm Hg in the overall population and -3.32 mm Hg in non-hypertensive subjects.Results from this meta-analysis show that IPP/VPP lactotripeptides can significantly reduce office SBP in Japanese subjects with or without overt hypertension, and for doses that can potentially be consumed as an everyday supplement. This suggests that these peptides could play a role in controlling blood pressure in Japanese subjects. The systematic review protocol was published on the PROSPERO register (CRD42014014322.

  10. A PILOT STUDY ON THE EFFECTS OF MAGNESIUM SUPPLEMENTATION WITH HIGH AND LOW HABITUAL DIETARY MAGNESIUM INTAKE ON RESTING AND RECOVERY FROM AEROBIC AND RESISTANCE EXERCISE AND SYSTOLIC BLOOD PRESSURE

    Directory of Open Access Journals (Sweden)

    Lindsy S. Kass

    2013-03-01

    Full Text Available The effects of magnesium supplementation on blood pressure (BP have been studied for over 25 years and results have been inconsistent. Blood pressure reductions in randomized studies have varied from 12 mmHg reductions to no reduction. The objective of this pilot intervention was to investigate the effect of magnesium supplementation on systolic blood pressure whilst resting and during recovery from aerobic and resistance exercise and on performance. A further objective was to see whether the effect of a high vs low habitual dietary magnesium intake affected these results. Sixteen male volunteers were randomly assigned to either a 300 mg·d-1 magnesium oxide supplementation (MO or a control group (CG for 14 days. Resting blood pressure (BP and heart rate (HR were measured before subjects performed a maximal 30 minute cycle, immediately followed by three x 5 second isometric bench press, both at baseline and after the intervention. Blood pressure and heart rate were recorded immediately post exercise and after five minutes recovery. A 3 day food diary was recorded for all subjects to measure dietary magnesium intake. At the end of the intervention, the supplemented group, had a reduction in mean resting systolic BP by 8.9 mmHg (115.125 ± 9.46 mmHg, p = 0.01 and post exercise by 13 mmHg (122.625 ± 9. 88 mmHg, p = 0.01. Recovery BP was 11.9 mmHg lower in the intervention group compared to control (p = 0.006 and HR decreased by 7 beats per minute in the experimental group (69.0 ± 11.6 bpm, p = 0. 02. Performance indicators did not change within and between the groups. Habitual dietary magnesium intake affected both resting and post exercise systolic BP and the subsequent effect of the magnesium supplementation. These results have an implication in a health setting and for health and exercise but not performance.

  11. 收缩压和LDL-C对颈动脉斑块的影响%Effects of systolic blood pressure and low density lipoprotein on carotid plaques

    Institute of Scientific and Technical Information of China (English)

    姚涛; 李雯; 张晓辉; 孙静; 王德胜; 赵永猛; 王张锋; 赵性泉; 吴寿岭

    2012-01-01

    Objective To explore the different effects of systolic blood pressure(SBP) and low density lipoprotein on carotid plaques(LDL-C).Methods A total of 101 510 serving and retired workers of a company who participated in the health examination in 2006-2009,5852 participants were selected as study subjects by stratified random sampling according to the age and sex ratio.These subjects took their health examination in 2010-2011 including the carotid ultrasound.Finally,5361 eligible participants with complete data were included in the analysis.The detection and weighted rates of carotid plaques were calculated for four groups:normal SBP and LDL-C group (3524 subjects),normal SBP and high LDL-C group (356 subjects),elevated SBP and normal LDL-C group (1308 subjects) and elevated SBP and high LDL-C group (173 subjects).The effects of different baseline SBP and LDL-C on detection rates of the carotid artery plaques were analyzed by logistic regression.Results The detection rate of carotid plaques in normal SBP and LDL-C group,normal SBP and high LDL-C group,elevated SBP and normal LDL-C group,elevated SBP and high LDL-C group was 33.7% (1186/3524),41.3% (147/356),64.8% (847/1308),68.8% (119/173) (x2 =425.75,P < 0.05) and the weighted detection rate was 36.0%,42.0%,64.5%and 68.3 % respectively.For men,the detection rate was 44.2% (877/1985),51.1% (97/190),70.6%(657/930),71.3% (82/1 15) (x2 =194.02,P < 0.05) and the weighted detection rate was 31.2%,36.1%,49.8% and 50.3% respectively.For women,the detection rate was 20.1% (309/1539),30.1%(50/166),50.3% (190/378),63.8% (37/58) (x2 =180.17,P < 0.05) and the weighted detection rate was 30.9%,46.3%,70.3%,and 88.1% respectively.After adjusted for other risk factors,the OR (95 % CI) value was 1.37 (1.05-1.78),2.05 (1.74-2.43) and 2.12 (1.45-3.12) for normal SBP and high LDL-C group,elevated SBP and normal LDL-C group and elevated SBP and high LDL-C group respectively compared

  12. Real-time stereo matching architecture based on 2D MRF model: a memory-efficient systolic array

    Directory of Open Access Journals (Sweden)

    Park Sungchan

    2011-01-01

    Full Text Available Abstract There is a growing need in computer vision applications for stereopsis, requiring not only accurate distance but also fast and compact physical implementation. Global energy minimization techniques provide remarkably precise results. But they suffer from huge computational complexity. One of the main challenges is to parallelize the iterative computation, solving the memory access problem between the big external memory and the massive processors. Remarkable memory saving can be obtained with our memory reduction scheme, and our new architecture is a systolic array. If we expand it into N's multiple chips in a cascaded manner, we can cope with various ranges of image resolutions. We have realized it using the FPGA technology. Our architecture records 19 times smaller memory than the global minimization technique, which is a principal step toward real-time chip implementation of the various iterative image processing algorithms with tiny and distributed memory resources like optical flow, image restoration, etc.

  13. 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

    models which reflect the disease process. Material and Results: We randomly allocated 45 newborn pigs, at the age of 48 hrs, to groups in which there was either construction of a 3 mm central aorto-pulmonary shunt, undertaken in 9, or ligation of the left pulmonary artery, achieved in 13. Controls...... 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....... 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...

  14. AVR单片机下脉搏传导时间与收缩压的关系%Research on pulse transit time and systolic blood pressure with AVR microcontroller

    Institute of Scientific and Technical Information of China (English)

    王帅; 刘力夫; 沙宪政

    2015-01-01

    Objective The relationship between pulse transit time ( PTT) and invasive systolic blood pressure is analyzed with the data in MIMIC Database� A signal acquisition system which can obtain real time ECG and pulse signal is developed with AVR microcontroller and PC to analyze the relationship between the noninvasive systolic pressure and PTT� Methods Signals of 5 persons in the MIMIC Database are handled with Matlab software� The correlation coefficient between PTT and invasive systolic pressure is obtained� Six recruited normotensive male subjects ( aged 27 to 31 years) are tested with the system� Data of ECG signals and PPG signals are sent to PC via blue tooth� Then a two⁃month repeatability test is conducted on 4 subjects to test if there is a big change in the same subject� Results PPT has good linear relation with both invasive and noninvasive systolic pressure� Better linear relation can be achieved when the trough of the pulse wave is used as the characteristic point� Conclusions AVR data acquisition system is compact, portable, and can be applied in home care.%目的:利用MIMIC Datebase( mimicdb)数据分析有创收缩压和脉搏传导时间( pulse transit time, PTT)的关系。制作AVR信号采集系统,并在PC下采集心电和脉搏的实时信号,分析无创收缩压和PTT的关系。方法利用Matlab软件分析MIMIC数据库内5个个体的数据,得出PTT和有创收缩压的相关系数。利用AVR单片机采集用6名正常血压的男性(年龄27~31周岁)的心电和脉搏信号,用蓝牙发送至计算机。通过两个月对比试验,比较PTT和收缩压之间的关系是否发生很大的变化。结果PTT同有创和无创收缩压都有较好的线性相关性,波谷作为PTT特征点和收缩压有更好的线性关系。结论 AVR数据采集系统小巧、便携,可应用于家用监护。

  15. Bone mass loss is associated with systolic blood pressure in postmenopausal women with type 2 diabetes in Tibet: a retrospective cross-sectional study.

    Science.gov (United States)

    Zhou, L; Song, J; Yang, S; Meng, S; Lv, X; Yue, J; Mina, A; Puchi, B; Geng, Y; Yang, L

    2017-02-02

    We conducted an observational cross-section study to investigate the status of bone mineral mass of Tibetan postmenopausal women with type 2 diabetes and the possible predictors for osteoporosis. We found that prevalence of osteoporosis was 27.0% and blood pressure was an independent risk factor for bone mass loss.

  16. The risk of diabetic renal function impairment in the first decade after diagnosed of diabetes mellitus is correlated with high variability of visit-to-visit systolic and diastolic blood pressure: a case control study.

    Science.gov (United States)

    Yeh, Chi-Hsiao; Yu, Hsiu-Chin; Huang, Tzu-Yen; Huang, Pin-Fu; Wang, Yao-Chang; Chen, Tzu-Ping; Yin, Shun-Ying

    2017-03-22

    The variability of visit-to-visit (VVV) in systolic blood pressure (SBP) and diastolic blood pressure (DBP) is proved as a predictor of renal function deterioration in patients with non-diabetic chronic kidney disease. The purpose of this study was to investigate the relationship of the variability in SBP and the magnitude of renal function impairment for normal renal function patients in the first 10-years diagnosed with type II diabetes mellitus (DM). We retrospectively reviewed the electronic medical records of 789 patients who were first diagnosed with diabetes mellitus during 2000-2002 and regularly followed for 10 years with a total of 53,284 clinic visits. The stages of Chronic Kidney Disease (CKD) of every patient were determined using estimated glomerular filtration rate. The occurrence of nephropathy was defined in those patients whose CKD stages elevated equal or larger than three. Patients were categorized according to the VVV of systolic and diastolic BP into three groups. Patients with high VVV of both SBP and DBP had a 2.44 fold (95% CI: 1.88-3.17, p risk of renal function impairment compared with patients with low VVV of both SBP and DBP. Risk of renal function impairment for patients with high VVV of either SBP or DBP had a 1.43-fold increase (95% CI: 1.08-1.89, p = 0.012) compared with patients with low VVV of both SBP and DBP. Cox regression analysis also demonstrated that every 1-year increase of DM diagnosed age significantly raised the risk of renal function impairment with a hazard ration of 1.05 (95% CI: 1.04-1.06, p < 0.001). Not only VVV of SBP but also VVV in DBP is correlated with diabetic nephropathy in the first decade for patients diagnosed with type 2 DM.

  17. Inverse-model-based cuffless blood pressure estimation using a single photoplethysmography sensor.

    Science.gov (United States)

    Suzuki, Arata

    2015-07-01

    This paper proposes an inverse-model-based cuffless method for estimating blood pressure using a single photoplethysmography sensor. The proposed method, which is based on the relationship between blood pressure and the features of pulse waves, employs an inverse estimation and uses the blood pressure as the explanatory variable. Using this method, the blood pressure can be estimated with high accuracy even in situations where the pulse wave features are scattered, as the method uses the dynamic signal-to-noise ratio of the Taguchi method. In order to verify the effectiveness of the proposed method, we employed it to measure the systolic blood pressure. It could be confirmed that the estimation accuracy of the proposed method is higher than that of similar methods.

  18. Association of Hypothyroidism with Body Mass Index, Systolic Blood Pressure and Proteinuria in Diabetic Patients: Does treated Hypothyroidism with Thyroxine Replacement Therapy Prevent Nephropathy/Chronic Renal Disease?

    Science.gov (United States)

    Aziz, Kamran M A

    2016-01-01

    Untreated or sub-clinical hypothyroidism is associated with insulin resistance, obesity, adverse effects on cardiovascular system, hypertension and in turn risk of nephropathy. However, these changes are reversible with thyroxine replacement therapy (TRT). Current research studied 4235 diabetic patients, divided into two groups, those with clinical hypothyroidism /on TRT, compared to those without thyroid disease or undiagnosed. BMI, blood pressure, creatinine, urine microalbumin and spot urine protein levels were compared between these two groups. Study finding demonstrated that for hypothyroid cases, BMI was higher (32.2 ± 7.44 versus 29.4 ± 5.7; p hypothyroidism (on TRT) was strongly associated with obesity (p hypothyroidism.

  19. A blood circulation model for reference man

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, R.W.; Eckerman, K.F. [Oak Ridge National Lab., TN (United States). Health Sciences Research Div.; Williams, L.R. [Indiana Univ., South Bend, IN (United States). Div. of Liberal Arts and Sciences

    1999-01-01

    This paper describes a dynamic blood circulation model that predicts the movement and gradual dispersal of a bolus of material in the circulation after its intravascular injection into an adult human. The main purpose of the model is to improve the dosimetry of internally deposited radionuclides that decay in the circulation to a significant extent. The total blood volume is partitioned into the blood contents of 24 separate organs or tissues, right heart chambers, left heart chambers, pulmonary circulation, arterial outflow to the systemic tissues (aorta and large arteries), and venous return from the systemic tissues (large veins). As a compromise between physical reality and computational simplicity, the circulation of blood is viewed as a system of first-order transfers between blood pools, with the delay time depending on the mean transit time across the pool. The model allows consideration of incomplete, tissue-dependent extraction of material during passage through the circulation and return of material from tissues to plasma.

  20. Systolic and diastolic short-term blood pressure variability and its determinants in patients with controlled and uncontrolled hypertension: a retrospective cohort study.

    Science.gov (United States)

    Pengo, Martino F; Rossitto, Giacomo; Bisogni, Valeria; Piazza, Daniele; Frigo, Anna Chiara; Seccia, Teresa Maria; Maiolino, Giuseppe; Rossi, Gian Paolo; Pessina, Achille C; Calò, Lorenzo A

    2015-04-01

    Absolute blood pressure (BP) values are not the only causes of adverse cardiovascular consequences. BP variability (BPV) has also been demonstrated to be a predictor of mortality for cardiovascular events; however, its determinants are still unknown. This study considers 426 subjects with ambulatory BP monitoring (ABPM) measuring 24-h, diurnal and nocturnal absolute BP values and their standard deviations of the mean, along with nocturnal fall, age, sex and current treatment. Patients were divided in two subgroups, controlled and uncontrolled BP, and BPV of patients with "true" and "false" resistant hypertension was also analyzed. Nocturnal and 24-h BPV were higher in the group with uncontrolled hypertension. Multiple regression analysis showed that absolute BP, age, nocturnal fall, but not sex predicted BPV. Patients with "true" resistant hypertension had greater BPV than "false" resistant hypertension patients. Absolute BP resulted as the main determinant of 24-h and nocturnal BPV but not daytime BPV. Also nocturnal BP fall and age resulted as predictors of BPV in treated and untreated patients. Patients with "true" resistant hypertension have a higher BPV, suggesting a higher sympathetic activation. Evidence is still limited regarding the importance of short-term BPV as a prognostic factor and assessment of BPV cannot yet represent a parameter for routine use in clinical practice. Future prospective trials are necessary to define which targets of BPV can be achieved with antihypertensive drugs and whether treatment-induced reduction in BPV is accompanied by a corresponding reduction in cardiovascular events.

  1. Impaired systolic blood dipping and nocturnal hypertension: an independent predictor of carotid intima-media thickness in type 1 diabetic patients.

    Science.gov (United States)

    Atabek, Mehmet Emre; Akyürek, Nesibe; Eklioglu, Beray Selver; Alp, Hayrullah

    2014-01-01

    Type 1 diabetes in children predicts a broad range of later health problems including an increased risk of cardiovascular morbidity and mortality. This study aimed to evaluate whether nocturnal hypertension and impaired nocturnal dipping affect atherosclerosis in children and adolescents with type 1 diabetes and to investigate the relationship between atherogenic risk factors and carotid intima-media thickness (CIMT). One hundred fifty-nine type 1 diabetic patients and 100 healthy controls were included in the study. We investigated metabolic and anthropometric parameters such as body mass index (BMI), waist circumference, fasting glucose and insulin, serum lipids, 24h ambulatory blood pressure monitoring (ABPM), and CIMT and compared these with those in control subjects (CS). No difference was found between type 1 diabetic patients and CS in age, weight, waist/hip ratio, triglyceride, HDL-cholesterol level. However in children with type 1 diabetes, total cholesterol (p=0.016),and LDL-cholesterol (p=0.002) levels and CIMT (Pimportant to note that our findings reveal significant relationships between HBA1c cardiovascular changes and underline the importance of glucose control to predict CVD. © 2014.

  2. Effects of self breathing exercise on heart rate and systolic blood pressure in adults:a Meta-analysis%自主呼吸锻炼对成人心率、收缩压影响的 Meta 分析

    Institute of Scientific and Technical Information of China (English)

    黄慧; 张艳云; 陈燕; 汪小华; 李月琴

    2016-01-01

    Objective To review the effects of self breathing exercise (SBE)on heart rate and systolic blood pressure in adults.Methods We electronically searched databases including CENTRAL (Cochrane Central Register of Controlled Trials),MEDLINE,EMbase,PEDro,OVID,CNKI,VIP,WanFang Data and CBMfrom the establishment of database to November 2014 to identify randomized controlled trials (RCTs)of VBE and references.Two researchers assessed data according to PEDro,and the effective data was used by Meta analysis which met the including criteria.The statistical analysis used RevMan 5.0 software.Results A total of 5 RCTs were included.The results of meta-analysis showed that the effects of VBE on heart rate and systolic blood pressure in adults was statistically significant compared with control group (P <0.05).Conclusions The self breathing excise can decline adult heart rate and systolic blood pressure with low adverse effects,and it is easy to operate and is a favorable physical therapy method,which can be recommended to self health care and disease rehabilitation nursing.%目的:评价自主呼吸锻炼对成年人心率、收缩压的影响。方法计算机检索 CENTRAL (Cochrane Central Register of Controlled Trials)、MEDLINE、EMbase、PEDro、OVID、中国知网(CNKI)、维普数据库(VlP)、万方数据库(Wanfang Data)和中国生物医学文献数据库(CBM)。所有关于自主呼吸锻炼的随机对照试验,检索时限均为从建库至2014年11月,同时追索纳入文献的参考文献。由2名研究者根据 PEDro 量表进行评价,对符合纳入标准的 RCT 提取有效数据进行 Meta 分析。统计学分析采用RevMan 5.0软件。结果共纳入5项随机对照试验(RCT)。Meta 分析结果显示与对照组相比,自主呼吸锻炼对成年人心率、收缩压影响的差异均有统计学意义(P <0.05)。结论自主呼吸锻炼能够降低成年人的心率、收缩压,且不良反应甚小,操

  3. 沙格列汀对改善2型糖尿病患者血压的效果及其作用机制%Saxagliptin decreases systolic blood pressure in patients with type 2 diabetes

    Institute of Scientific and Technical Information of China (English)

    曾建; 陈晓军

    2015-01-01

    Objective To investigate the blood pressure-lowing effects of saxagliptin in patients with type 2 diabetes, to study the mechanisms of the beneficial effects of saxagliptin on heart and blood vessels .Methods 78 patients with type 2 diabetes mellitus failing in blood glucose control but with stabilized blood pressure or not having their hypotensive drugs changed over the previous three months were randomly divided into study group (43) and control group(35).The study group was treated with saxagliptin while the control group received increased original dose or added with other hypoglycemic agents for three months .Then the levels of fasting and postprandial blood glucose,glycosylated hemoglobin(HbA1c),body mass index(BMI),and blood pressure were measured after thera-py.Results The fasting plasma glucose (FPG), postprandial glucose (PPG) and HbA1c significantly decreased after treatment in the two groups (P<0.05);while the systolic blood pressure (SBP) [ (133.9 ±16.5) mmHg vs (125.2 ±13.4) mmHg),P<0.01], 24 h mean systolic blood pressure [ (125.2 ±11.7) mmHg vs (116.6 ±8.6) mmHg,P<0.01] decreased significantly in treatment group after treatment , but no significant change in the control group .However , the degree of the decrease in HbA 1 c、FPG and PPG levels was not significantly correlated with that of SBP by Spearman rank correlation .Conclusions Saxagliptin decreases not only blood glucose but also systolic pressure in patients with type 2 diabetes mellitus .%目的:观察沙格列汀改善2型糖尿病(type 2 diabetes mellitus,T2DM)患者血压的效果,并探讨其心血管保护作用的机制。方法选取血糖控制不佳而血压控制平稳的T2DM 78例,随机分为治疗组43例和对照组35例,两组在原有口服药物基础上,治疗组加用沙格列汀,对照组增加原有药物剂量或加用其他降糖药。治疗3个月后,观察两组治疗前后血糖、糖化血红蛋白( HbA1 c)、体重指数( BMI)及

  4. Multilevel analysis of systolic blood pressure and ACE gene I/D polymorphism in 438 Swedish families – a public health perspective

    Directory of Open Access Journals (Sweden)

    Råstam Lennart

    2006-03-01

    Full Text Available Abstract Background Individuals belonging to the same family share a number of genetic as well as environmental circumstances that may condition a common SBP level. Among the genetic factors, the angiotensin converting enzyme (ACE gene I/D polymorphism appears as a possible candidate as it might influence both SBP and the pharmacological effect of ACE inhibitors. We aimed to combine genetic epidemiology with public health ideas concerning life-course and multilevel epidemiology in order to understand the role of familial factors regarding individual SBP. Methods We applied multilevel regression analysis on 1926 individuals nested within 438 families from South Sweden. Modelling familial SBP variance as a function of age and use of ACE inhibitors we calculates a variance partition coefficient and the proportional change in familial SBP variance attributable to differences in ACE gene I/D polymorphism Results Our results suggest the existence of genetic or environmental circumstances that produce a considerable familial clustering of SBP, especially among individuals using ACE-inhibitors. However, ACE gene I/D polymorphism seems to play a minor role in this context. In addition, familial factors – genetic, environmental or their interaction – shape SBP among non-users of ACE inhibitors but their effect is expressed later in the life-course. Conclusion Strategies directed to prevent hypertension should be launched in younger rather than in older ages and both prevention of hypertension and its treatment with ACE inhibitors should be focused on families rather than on individuals.

  5. Effects of parental hypertension on longitudinal trends in blood pressure and plasma metabolic profile: mixed-effects model analysis.

    Science.gov (United States)

    Mitsumata, Kaneto; Saitoh, Shigeyuki; Ohnishi, Hirofumi; Akasaka, Hiroshi; Miura, Tetsuji

    2012-11-01

    The mechanism underlying the association of parental hypertension with cardiovascular events in offspring remains unclear. In this study, the effects of parental hypertension on longitudinal trends of blood pressure and metabolic parameters were examined by mixed-effects model analysis. From 1977 to 2006, 5198 subjects participated in the Tanno-Sobetsu Study, and we selected 2607 subjects (1095 men and 1512 women) for whom data on parental history of hypertension were available. In both men and women with and without parental hypertension, systolic blood pressure and fasting blood glucose levels consistently increased from the third to eighth decades of life, whereas diastolic blood pressure and serum triglyceride levels followed biphasic (inverted U shape) time courses during that period. However, the relationships between the parameters and age were significantly shifted upward (by ≈5.3 mm Hg in systolic blood pressure, 2.8 mm Hg in diastolic blood pressure, 0.30 mmol/L in blood glucose, and 0.09 mmol/L in triglyceride) in the group with parental hypertension compared with those in the group without parental hypertension. Both paternal and maternal histories of hypertension were determinants of systolic blood pressure and diastolic blood pressure, and there was no significant interaction between the sides of parental history. There were no significant effects of parental hypertension on age-dependent or body mass index-dependent changes in serum low-density lipoprotein cholesterol or high-density lipoprotein cholesterol level. The present results indicate that parental hypertension has an age-independent impact on elevation of blood pressure, plasma glucose, and triglyceride levels, which may underlie the reported increase in cardiovascular events by family history of hypertension.

  6. THE INFLUENCE OF BIOFEEDBACK SESSIONS IN CLOSED LOOP OF HEART RATE VARIABILITY AND PACED BREATHING ON SYSTOLIC BLOOD PRESSURE CONTROL DURING STANDARD DRUG THERAPY IN PATIENTS WITH ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    S. A. S. Belal

    2015-06-01

    Full Text Available Changes of systolic blood pressure (SBP in biofeedback (BFB sessions with closed loop of paced breathing (PB and heart rate variability (HRV during standard drug therapy of arterial hypertension (AH was studied. 275 patients with 1-3 degree of AH (143 men and 132 women, mean age 58,55 ± 7,99 years was divided into two comparable groups: 1 - BFB (139 patients in investigated PB loop, 2 - control group (136 patients with BFB without PB. In both groups was performed 10 sessions of BFB. Changes of SBP depending on the stage and degree of AH, gender and age was assessed. BP was measured by the method of Korotkov’s with monometer Microlife BP AG1-20 in same conditions. Data were processed by parametric and nonparametric statistics. It is proved that the use of biofeedback in the loop of PB and HRV significantly (p < 0.01 exceeds in efficiency an isolated drug therapy in control of SBP at any stage and degree of AH in patients of both sexes in all age groups. Extent of the effect increases with the stage and degree of the disease and not related to the sex and age of the patient. Findings allow to recommend this technique in clinical practice.

  7. Effect of magnesium supplementation on blood rheology in NOS inhibition-induced hypertension model.

    Science.gov (United States)

    Cengiz, Melike; Ülker, Pinar; Üyüklü, Mehmet; Yaraş, Nazmi; Özen, Nur; Aslan, Mutay; Özyurt, Dilek; Basralı, Filiz

    2016-01-27

    This study investigated the effects of magnesium on blood rheological properties and blood pressure in nitric oxide synthase (NOS) inhibition-induced hypertension model. Hypertension was induced by oral administration of the nonselective NOS inhibitor N-nitro-L-arginine methyl ester (L-NAME, 25 mg/kg/day) for 6 weeks and systolic blood pressure was measured by the tail-cuff method. The groups receiving magnesium supplementation were fed with rat chow containing 0.8% magnesium oxide during the experiment. At the end of experiment, blood samples were obtained from abdominal aorta, using ether anesthesia. Plasma and erythrocyte magnesium levels were determined by the atomic absorption spectrometer. RBC deformability and aggregation were determined by rotational ektacytometry. Plasma fibrinogen concentration was evaluated by ELISA. Whole blood and plasma viscosities were determined by viscometer and intracellular free Ca++ level was measured by using spectroflurometric method. Blood pressure was elevated in hypertensive groups and suppressed by magnesium therapy. Plasma viscosity and RBC aggregation were found to be higher in hypertensive rats than control animals and these parameters significantly decreased in magnesium supplemented hypertensive animals. Other measurements were not different between experimental groups. These results confirm that blood pressure, plasma viscosity and RBC aggregation increased in NOS inhibition-induced hypertension model and oral magnesium supplementation improved these parameters.

  8. Both high and low plasma levels of 25-hydroxy vitamin D increase blood pressure in a normal rat model.

    Science.gov (United States)

    Mirhosseini, Naghmeh Z; Knaus, Steven J; Bohaychuk, Kaylee; Singh, Jaswant; Vatanparast, Hassan A; Weber, Lynn P

    2016-12-01

    The lower threshold plasma 25-hydroxy vitamin D (25(OH)D) level for optimal cardiovascular health is unclear, whereas the toxicity threshold is less clear. The aim of this study was to examine the cardiovascular-vitamin D dose-response curve in a normal rat model. Doses of cholecalciferol ranged from deficiency to toxic levels (equivalent to human doses of 0, 0·015, 0·25 and 3·75mg/d) for 4 weeks, and then cardiovascular health was examined using blood pressure telemetry and high-resolution ultrasound in normal male rats (n 16/group, 64 rats total). After 1 month, only the 0·25mg/d group had plasma 25(OH)D that was within current recommended range (100-125 nmol/l), and all groups failed to change plasma Ca or phosphate. Systolic blood pressure increased significantly (10-15 mmHg) in the rat groups with plasma 25(OH)D levels at both 30 and 561 nmol/l (groups fed 0 and 3·75mg/d) compared with the group fed the equivalent to 0·015mg/d (43 nmol/l 25(OH)D). Although not significant, the group fed the equivalent to 0·25mg/d (108 nmol/l 25(OH)D) also showed a 10 mmHg increase in systolic blood pressure. Carotid artery diameter was significantly smaller and wall thickness was larger, leading to higher peak carotid systolic blood velocity in these two groups. Despite these vascular changes, cardiac function did not differ among treatment groups. The key finding in this study is that arterial stiffness and systolic blood pressure both showed a U-shaped dose-response for vitamin D, with lowest values (best cardiovascular health) observed when plasma 25(OH)D levels were 43 nmol/l in normal male rats.

  9. ATLS Hypovolemic Shock Classification by Prediction of Blood Loss in Rats Using Regression Models.

    Science.gov (United States)

    Choi, Soo Beom; Choi, Joon Yul; Park, Jee Soo; Kim, Deok Won

    2016-07-01

    In our previous study, our input data set consisted of 78 rats, the blood loss in percent as a dependent variable, and 11 independent variables (heart rate, systolic blood pressure, diastolic blood pressure, mean arterial pressure, pulse pressure, respiration rate, temperature, perfusion index, lactate concentration, shock index, and new index (lactate concentration/perfusion)). The machine learning methods for multicategory classification were applied to a rat model in acute hemorrhage to predict the four Advanced Trauma Life Support (ATLS) hypovolemic shock classes for triage in our previous study. However, multicategory classification is much more difficult and complicated than binary classification. We introduce a simple approach for classifying ATLS hypovolaemic shock class by predicting blood loss in percent using support vector regression and multivariate linear regression (MLR). We also compared the performance of the classification models using absolute and relative vital signs. The accuracies of support vector regression and MLR models with relative values by predicting blood loss in percent were 88.5% and 84.6%, respectively. These were better than the best accuracy of 80.8% of the direct multicategory classification using the support vector machine one-versus-one model in our previous study for the same validation data set. Moreover, the simple MLR models with both absolute and relative values could provide possibility of the future clinical decision support system for ATLS classification. The perfusion index and new index were more appropriate with relative changes than absolute values.

  10. 不同收缩压水平对臂踝脉搏波传导速度影响的研究%Effect of different levels of systolic blood pressure on brachial-ankle pulse wave velocity

    Institute of Scientific and Technical Information of China (English)

    王义; 陶杰; 董岩; 陈朔华; 高新颖; 季春鹏; 杨光; 郑瑶; 吴寿岭

    2014-01-01

    Objective To investigate the impact of different levels of systolic blood pressure on brachial-ankle pulse wave velocity(baPWV). Methods A total of 5 852 participants was selected with stratified random sampling from the 101 510 workers of Tangshan Kaiuan Company who had undergone a physical check-up program. 5 222 of them with integral data were recruited into this survey. According to SBP collected during the 2010-2011 health examination program,the population under observation was divided into four groups:optimal SBP(SBP<120 mmHg),high-normal blood pressure Ⅰ period(120 mmHg≤SBP<130 mmHg),high-normal blood pressure Ⅱ period (130 mmHg≤SBP<140 mmHg)and hypertension(SBP≥140 mmHg or SBP<140 mmHg but antihypertensive drug user). Multivariate logistic regression analysis was used to analyze the influence of different levels of systolic blood pressure on baPWV. Results 1)There were 3 132 males and 2 090 females in all the 5 222 participants with an average age of 55.1 years old. Their mean of baPWV was(1 587.57±400.71)cm/s,with the detection rates as 62%(baPWV≥1 400 cm/s). 2)The means of baPWV for the above groups of SBP were 1 322.19,1 456.27,1 544.78 and 1 827.77 cm/s, respectively,with detection rates of baPWV≥1 400 cm/s as 26.4%,49.3%,64.2% and 88.3%, respectively. 3)Results from the Multiple linear regression analysis revealed that β of SBP was 0.40,only ranking second,on age(0.48). 4)Data from the Multiple logistic regression analysis showed that after adjusting for age,gender and other risk factors,when compared to optimal SBP,factors as high-normal blood pressure Ⅰ period、high-normal blood pressure Ⅱ period and hypertension were risk factors for increasing baPWV,with OR values as 2.70(95%CI:2.20-3.32),4.56(95%CI:3.67-5.67)and 13.51(95%CI:10.87-16.78),respectively. Conclusion Higher SBP seemed an independent risk factor for the increase of baPWV.%目的:探讨不同收缩压(SBP)水平对臂踝脉搏波传导速度

  11. Blood pressure measurement

    Science.gov (United States)

    Diastolic blood pressure; Systolic blood pressure; Blood pressure reading; Measuring blood pressure ... or your health care provider will wrap the blood pressure cuff snugly around your upper arm. The lower ...

  12. Systolic implementation of neural networks

    Energy Technology Data Exchange (ETDEWEB)

    De Groot, A.J.; Parker, S.R.

    1989-01-01

    The backpropagation algorithm for error gradient calculations in multilayer, feed-forward neural networks is derived in matrix form involving inner and outer products. It is demonstrated that these calculations can be carried out efficiently using systolic processing techniques, particularly using the SPRINT, a 64-element systolic processor developed at Lawrence Livermore National Laboratory. This machine contains one million synapses, and forward-propagates 12 million connections per second, using 100 watts of power. When executing the algorithm, each SPRINT processor performs useful work 97% of the time. The theory and applications are confirmed by some nontrivial examples involving seismic signal recognition. 4 refs., 7 figs.

  13. Hyper-systolic matrix multiplication

    NARCIS (Netherlands)

    Lippert, Th.; Petkov, N.; Palazzari, P.; Schilling, K.

    2001-01-01

    A novel parallel algorithm for matrix multiplication is presented. It is based on a 1-D hyper-systolic processor abstraction. The procedure can be implemented on all types of parallel systems. (C) 2001 Elsevier Science B,V. All rights reserved.

  14. Effects of Heme Oxygenase-1 Upregulation on Blood Pressure and Cardiac Function in an Animal Model of Hypertensive Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Lin Liu

    2013-01-01

    Full Text Available In this study, we evaluate the effect of HO-1 upregulation on blood pressure and cardiac function in the new model of infarct spontaneous hypertensive rats (ISHR. Male spontaneous hypertensive rats (SHR at 13 weeks (n = 40 and age-matched male Wistar (WT rats (n = 20 were divided into six groups: WT (sham + normal saline (NS, WT (sham + Co(III Protoporphyrin IX Chloride (CoPP, SHR (myocardial infarction (MI + NS, SHR (MI + CoPP, SHR (MI + CoPP + Tin Mesoporphyrin IX Dichloride (SnMP, SHR (sham + NS; CoPP 4.5 mg/kg, SnMP 15 mg/kg, for six weeks, one/week, i.p., n = 10/group. At the sixth week, echocardiography (UCG and hemodynamics were performed. Then, blood samples and heart tissue were collected. Copp treatment in the SHR (MI + CoPP group lowered blood pressure, decreased infarcted area, restored cardiac function (left ventricular ejection fraction (LVEF, left ventricular fraction shortening (LVFS, +dp/dtmax, (−dp/dtmax/left ventricular systolic pressure (LVSP, inhibited cardiac hypertrophy and ventricular enlargement (downregulating left ventricular end-systolic diameter (LVEDD, left ventricular end-systolic diameter (LVESD and heart weight/body weight (HW/BW, lowered serum CRP, IL-6 and Glu levels and increased serum TB, NO and PGI2 levels. Western blot and immunohistochemistry showed that HO-1 expression was elevated in the SHR (MI + CoPP group, while co-administration with SnMP suppressed the benefit functions mentioned above. In conclusion, HO-1 upregulation can lower blood pressure and improve post-infarct cardiac function in the ISHR model. These functions may be involved in the inhibition of inflammation and the ventricular remodeling process and in the amelioration of glucose metabolism and endothelial dysfunction.

  15. A Systolic Array RLS Processor

    OpenAIRE

    Asai, T.; Matsumoto, T.

    2000-01-01

    This paper presents the outline of the systolic array recursive least-squares (RLS) processor prototyped primarily with the aim of broadband mobile communication applications. To execute the RLS algorithm effectively, this processor uses an orthogonal triangularization technique known in matrix algebra as QR decomposition for parallel pipelined processing. The processor board comprises 19 application-specific integrated circuit chips, each with approximately one million gates. Thirty-two bit ...

  16. Preparation of Blood-Deficient Model and Research of Angelica Polysaccharide on Enriching Blood in Chickens

    OpenAIRE

    Haifeng Hou; Yongzhan Bao; Qian Li; Wanyu Shi

    2012-01-01

    In this study cyclophosphamide was used to prepare the blood-deficient model. The red blood cell count and hemoglobin content were measured. The experimental chickens presented the symptoms of blood-deficient syndrome, dullness, shrinkinginto oneself, broken winded, loose feather, waxy eyelid, and pale tongue. At the same time, red blood cell count and hemoglobin content decreased significantly. Angelica polysaccharide as the effective component of Angelica Sinensis could significantly increa...

  17. Modeling study of the failing heart and its interaction with an implantable rotary blood pump.

    Science.gov (United States)

    Ramachandran, Deepa P; Luo, Chuan; Ma, Tony S; Clark, John W

    2011-01-01

    The effectiveness of clinical diagnosis and treatment of heart failure is a direct function of clinical signs that can be measured in a patient within cost and safety constraints. Large-scale mathematical modeling can be a key tool in revealing important, measurable clinical signs of heart failure, furthering medical understanding and development of treatment. In the first part of this study we have created two models of left heart failure--diastolic and systolic, using our human cardiovascular-respiratory system (H-CRS) model, and we present a comparison of the two types with emphasis on novel and differentiating clinical signs, such as tricuspid flow and septal motion. In the event of compromised left ventricular performance, mechanical left ventricular assist devices (LVAD) are often implanted to augment or completely replace the pumping action of the left ventricle (LV). One such type is the implantable rotary blood pump (iRBP). Several design issues related to the iRBP are difficult to study experimentally due to procedure complexity and limitations in animal models of heart failure [2]. Therefore, modeling has become a key tool in iRBP development. In the second part of this study, we have introduced an iRBP model based on [1]-[2] in the systolic failing heart to study the interactions. We consider optimal motor settings for different levels of LV assistance, the effects of the iRBP on the right heart, septum, and pulmonary circulation. Our model results align with those reported in [1]-[2]. Improvement in cardiac output, pulmonary congestion, and heart work are seen with the iRBP. We observe lowered septal assistance to RV and LV ejection with increasing pump speeds, elevating right ventricular (RV) work, reducing LVET, and causing ventricular mechanical dyssynchrony in ejection. These results suggest right heart compromise via the septum's reduced role with the introduction of an iRBP. This work emphasizes the critical role of modeling in heart failure and

  18. Physiological Responses Associated with Nordic-Walking Training in Systolic Hypertensive Postmenopausal Women

    Directory of Open Access Journals (Sweden)

    Latosik Ewelina

    2014-12-01

    Full Text Available Loss of physical strength and hypertension are among the most pronounced detrimental factors accompanying aging. The aim of this study was to evaluate the influence of a supervised 8-week Nordic-walking training program on systolic blood pressure in systolic-hypertensive postmenopausal women. This study was a randomized control trial on a sample of 24 subjects who did not take any hypertension medications. There was a statistically significant decrease in systolic blood pressure and an increase in lower and upper-body strength in the group following Nordic-walking training. There was a decrease in serum levels of total cholesterol, triglycerides, and low-density cholesterol. The obtained results indicate that an 8-week Nordic-walking program may be efficiently employed for counteracting systolic hypertension through a direct abatement of systolic blood pressure and an increase of maximal aerobic capacity.

  19. Structural equation modeling with latent variables for longitudinal blood pressure traits using general pedigrees.

    Science.gov (United States)

    Song, Yeunjoo E; Morris, Nathan J; Stein, Catherine M

    2016-01-01

    Structural equation modeling (SEM) has been used in a wide range of applied sciences including genetic analysis. The recently developed R package, strum, implements a framework for SEM for general pedigree data. We explored different SEM techniques using strum to analyze the multivariate longitudinal data and to ultimately test the association of genotypes on blood pressure traits. The quantitative blood pressure (BP) traits, systolic BP (SBP) and diastolic BP (DBP) were analyzed as the main traits of interest with age, sex, and smoking status as covariates. The single nucleotide polymorphism (SNP) genotype information from genome-wide association studies (GWAS) data was used for the test of association. The adjustment for hypertension treatment effect was done by the censored regression approach. Two different longitudinal data models, autoregressive model and latent growth curve model, were used to fit the longitudinal BP traits. The test of association for SNP was done using a novel score test within the SEM framework of strum. We found the 10 SNPs within the GWAS suggestive P value level, and among those 10, the most significant top 3 SNPs agreed in rank in both analysis models. The general SEM framework in strum is very useful to model and test for the association with massive genotype data and complex systems of multiple phenotypes with general pedigree data.

  20. Multiscale modeling of blood flow: from single cells to blood rheology.

    Science.gov (United States)

    Fedosov, Dmitry A; Noguchi, Hiroshi; Gompper, Gerhard

    2014-04-01

    Mesoscale simulations of blood flow, where the red blood cells are described as deformable closed shells with a membrane characterized by bending rigidity and stretching elasticity, have made much progress in recent years to predict the flow behavior of blood cells and other components in various flows. To numerically investigate blood flow and blood-related processes in complex geometries, a highly efficient simulation technique for the plasma and solutes is essential. In this review, we focus on the behavior of single and several cells in shear and microcapillary flows, the shear-thinning behavior of blood and its relation to the blood cell structure and interactions, margination of white blood cells and platelets, and modeling hematologic diseases and disorders. Comparisons of the simulation predictions with existing experimental results are made whenever possible, and generally very satisfactory agreement is obtained.

  1. Numerical analysis of bypass model geometrical parameters influence on pulsatile blood flow

    Directory of Open Access Journals (Sweden)

    Jonášová A.

    2011-06-01

    Full Text Available The present study is focused on the analysis of pulsatile blood flow in complete idealized 3D bypass models in dependence on three main geometrical parameters (stenosis degree, junction angle and diameter ratio. Assuming the blood to be an incompressible Newtonian fluid, the non-linear system of Navier-Stokes equations is integrated in time by a fully implicit second-order accurate fractional-step method. The space discretization is performed with the help of the cell-centred finite volume method formulated for unstructured tetrahedral grids. In order to model a realistic coronary blood flow, a time-dependent flow rate taken from corresponding literature is considered. For the analysis of obtained numerical results, special emphasis is placed on their comparison in the form of velocity isolines at several selected cross-sections during systolic and diastolic phases. The remainder of this paper is devoted to discussion of walls shear stress distribution and its oscillatory character described by the oscillatory shear index with regard to areas prone to development of intimal hyperplasia or to thrombus formation.

  2. Mathematical Model of Extrinsic Blood Coagulation Cascade Dynamic System

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The blood coagulation system is very important to life. This paper presents a mathematical blood coagulation model for the extrinsic pathway. This model simulates clotting factor VIII, which plays an important role in the coagulation mechanism. The mathematical model is used to study the equilibrium stability, orbit structure, attractors and global stability behavior, with conclusions in accordance with the physiological phenomena. Moreover, the results provide information about blood related illnesses, which can be used for further study of the coagulation mechanism.

  3. Double product reflects the predictive power of systolic pressure in the general population

    DEFF Research Database (Denmark)

    Schutte, Rudolph; Thijs, Lutgarde; Asayama, Kei

    2013-01-01

    The double product (DP), consisting of the systolic blood pressure (SBP) multiplied by the pulse rate (PR), is an index of myocardial oxygen consumption, but its prognostic value in the general population remains unknown.......The double product (DP), consisting of the systolic blood pressure (SBP) multiplied by the pulse rate (PR), is an index of myocardial oxygen consumption, but its prognostic value in the general population remains unknown....

  4. A model for red blood cells in simulations of large-scale blood flows

    CERN Document Server

    Melchionna, Simone

    2011-01-01

    Red blood cells (RBCs) are an essential component of blood. A method to include the particulate nature of blood is introduced here with the goal of studying circulation in large-scale realistic vessels. The method uses a combination of the Lattice Boltzmann method (LBM) to account for the plasma motion, and a modified Molecular Dynamics scheme for the cellular motion. Numerical results illustrate the quality of the model in reproducing known rheological properties of blood as much as revealing the effect of RBC structuring on the wall shear stress, with consequences on the development of cardiovascular diseases.

  5. Infinite systolic groups are not torsion

    OpenAIRE

    Prytuła, Tomasz

    2014-01-01

    We study k-systolic complexes introduced by T. Januszkiewicz and J. \\'Swi\\k{a}tkowski, which are simply connected simplicial complexes of simplicial nonpositive curvature. Using techniques of filling diagrams we prove that for k > 6 the 1-skeleton of a k-systolic complex is Gromov hyperbolic. We give an elementary proof of so-called Projection Lemma, which implies contractibility of 6-systolic complexes. We also prove that an infinite group acting geometrically on a 6-systolic complex is not ...

  6. Numerical simulations of a reduced model for blood coagulation

    Science.gov (United States)

    Pavlova, Jevgenija; Fasano, Antonio; Sequeira, Adélia

    2016-04-01

    In this work, the three-dimensional numerical resolution of a complex mathematical model for the blood coagulation process is presented. The model was illustrated in Fasano et al. (Clin Hemorheol Microcirc 51:1-14, 2012), Pavlova et al. (Theor Biol 380:367-379, 2015). It incorporates the action of the biochemical and cellular components of blood as well as the effects of the flow. The model is characterized by a reduction in the biochemical network and considers the impact of the blood slip at the vessel wall. Numerical results showing the capacity of the model to predict different perturbations in the hemostatic system are discussed.

  7. 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.

  8. Natriuretic peptide vs. clinical information for diagnosis of left ventricular systolic dysfunction in primary care

    Directory of Open Access Journals (Sweden)

    Wachter Rolf

    2008-02-01

    Full Text Available Abstract Background Screening of primary care patients at risk for left ventricular systolic dysfunction by a simple blood-test might reduce referral rates for echocardiography. Whether or not natriuretic peptide testing is a useful and cost-effective diagnostic instrument in primary care settings, however, is still a matter of debate. Methods N-terminal pro-brain natriuretic peptide (NT-proBNP levels, clinical information, and echocardiographic data of left ventricular systolic function were collected in 542 family practice patients with at least one cardiovascular risk factor. We determined the diagnostic power of the NT-proBNP assessment in ruling out left ventricular systolic dysfunction and compared it to a risk score derived from a logistic regression model of easily acquired clinical information. Results 23 of 542 patients showed left ventricular systolic dysfunction. Both NT-proBNP and the clinical risk score consisting of dyspnea at exertion and ankle swelling, coronary artery disease and diuretic treatment showed excellent diagnostic power for ruling out left ventricular systolic dysfunction. AUC of NT-proBNP was 0.83 (95% CI, 0.75 to 0.92 with a sensitivity of 0.91 (95% CI, 0.71 to 0.98 and a specificity of 0.46 (95% CI, 0.41 to 0.50. AUC of the clinical risk score was 0.85 (95% CI, 0.79 to 0.91 with a sensitivity of 0.91 (95% CI, 0.71 to 0.98 and a specificity of 0.64 (95% CI, 0.59 to 0.67. 148 misclassifications using NT-proBNP and 55 using the clinical risk score revealed a significant difference (McNemar test; p Conclusion The evaluation of clinical information is at least as effective as NT-proBNP testing in ruling out left ventricular systolic dysfunction in family practice patients at risk. If these results are confirmed in larger cohorts and in different samples, family physicians should be encouraged to rely on the diagnostic power of the clinical information from their patients.

  9. Optical systolic solutions of linear algebraic equations

    Science.gov (United States)

    Neuman, C. P.; Casasent, D.

    1984-01-01

    The philosophy and data encoding possible in systolic array optical processor (SAOP) were reviewed. The multitude of linear algebraic operations achievable on this architecture is examined. These operations include such linear algebraic algorithms as: matrix-decomposition, direct and indirect solutions, implicit and explicit methods for partial differential equations, eigenvalue and eigenvector calculations, and singular value decomposition. This architecture can be utilized to realize general techniques for solving matrix linear and nonlinear algebraic equations, least mean square error solutions, FIR filters, and nested-loop algorithms for control engineering applications. The data flow and pipelining of operations, design of parallel algorithms and flexible architectures, application of these architectures to computationally intensive physical problems, error source modeling of optical processors, and matching of the computational needs of practical engineering problems to the capabilities of optical processors are emphasized.

  10. Real-Time Statistical Modeling of Blood Sugar.

    Science.gov (United States)

    Otoom, Mwaffaq; Alshraideh, Hussam; Almasaeid, Hisham M; López-de-Ipiña, Diego; Bravo, José

    2015-10-01

    Diabetes is considered a chronic disease that incurs various types of cost to the world. One major challenge in the control of Diabetes is the real time determination of the proper insulin dose. In this paper, we develop a prototype for real time blood sugar control, integrated with the cloud. Our system controls blood sugar by observing the blood sugar level and accordingly determining the appropriate insulin dose based on patient's historical data, all in real time and automatically. To determine the appropriate insulin dose, we propose two statistical models for modeling blood sugar profiles, namely ARIMA and Markov-based model. Our experiment used to evaluate the performance of the two models shows that the ARIMA model outperforms the Markov-based model in terms of prediction accuracy.

  11. PERFORMANCE MODELING AND ANALYSIS OF BLOOD FLOW IN ELASTIC ARTERIES

    Institute of Scientific and Technical Information of China (English)

    Anil Kumar; C.L. Varshney; G.C. Sharma

    2005-01-01

    Two different non-Newtonian models for blood flow are considered, first a simple power law model displaying shear thinning viscosity, and second a generalized Maxwell model displaying both shear thinning viscosity and oscillating flow viscous-elasticity. These models are used along with a Newtonian model to study sinusoidal flow of blood in rigid and elastic straight arteries in the presence of magnetic field. The elasticity of blood does not appear to influence its flow behavior under physiological conditions in the large arteries,purely viscous shear thinning model should be quite realistic for simulating blood flow under these conditions. On using the power law model with high shear rate for sinusoidal flow simulation in elastic arteries, the mean and amplitude of the flow rate were found to be lower for a power law fluid compared to Newtonian fluid for the same pressure gradient. The governing equations have been solved by Crank-Niclson scheme. The results are interpreted in the context of blood in the elastic arteries keeping the magnetic effects in view. For physiological flow simulation in the aorta, an increase in mean wall shear stress, but a reduction in peak wall shear stress were observed for power law model compared to a Newtonian fluid model for matched flow rate wave form. Blood flow in the presence of transverse magnetic field in an elastic artery is investigated and the influence of factors such as morphology and surface irregularity is evaluated.

  12. Rapid MR assessment of left ventricular systolic function after acute myocardial infarction using single breath-hold cine imaging with the temporal parallel acquisition technique (TPAT) and 4D guide-point modelling analysis of left ventricular function

    Energy Technology Data Exchange (ETDEWEB)

    Eberle, Holger C.; Jensen, Christoph J.; Sabin, Georg V.; Naber, Christoph K.; Bruder, Oliver [Elisabeth Hospital, Department of Cardiology and Angiology, Essen (Germany); Nassenstein, Kai; Schlosser, Thomas [University of Duisburg-Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen (Germany)

    2010-01-15

    We compared four-dimensional guide-point modelling left ventricular function analysis (4DVF) results of cine images in four short-axis and two long-axis slices acquired in a single breath-hold, obtained with the temporal parallel acquisition technique (TPAT), with standard left ventricular function (LVF) analysis results determined by the summation of discs method, in patients who had recently suffered myocardial infarction. Despite wall motion abnormalities, 4DVF yields results for left ventricular ejection fractions and end-diastolic and end-systolic volumes that are in excellent agreement with standard LVF analysis results in these patients. A shortened cardiac magnetic resonance (CMR) protocol using single breath-hold cine image acquisition could facilitate the assessment of left ventricular function soon after myocardial infarction in critically ill patients who are unable to comply with the multiple breath-holds required for standard LVF analysis. (orig.)

  13. Investigating the impact of non-Newtonian blood models within a heart pump.

    Science.gov (United States)

    Al-Azawy, Mohammed G; Turan, A; Revell, A

    2017-01-01

    A detailed computational fluid dynamics (CFD) study of transient, turbulent blood flow through a positive displacement left ventricular assist device is performed. Two common models for non-Newtonian blood flow are compared to the Newtonian model to investigate their impact on predicted levels of shear rate and wall shear stress. Given that both parameters are directly relevant to the evaluation of risk from thrombus and haemolysis, there is a need to assess the sensitivity to modelling non-Newtonian flow effects within a pulsatile turbulent flow, in order to identify levels of uncertainly in CFD. To capture the effects of turbulence, the elliptic blending Reynolds stress model is used in the present study, on account of superior performance of second moment closure schemes previously identified by the present authors. The CFD configuration includes two cyclically rotating valves and a moving pusher plate to periodically vary the chamber volume. An overset mesh algorithm is used for each instance of mesh motion, and a zero gap technique was employed to ensure full valve closure. The left ventricular assist device was operated at a pumping rate of 86 BPM (beats per minute) and a systolic duration of 40% of the pumping cycle, in line with existing experimental data to which comparisons are made. The sensitivity of the variable viscosity models is investigated in terms of mean flow field, levels of turbulence and global shear rate, and a non-dimensional index is used to directly evaluate the impact of non-Newtonian effects. The clinical relevance of the results is reported along with a discussion of modelling uncertainties, observing that the turbulent kinetic energy is generally predicted to be higher in non-Newtonian flow than that observed in Newtonian flow. Copyright © 2016 John Wiley & Sons, Ltd.

  14. Effect of Elevated Blood Pressure Treatment on Outcome of Acute Watershed Infarction ;with High Systolic Blood Pressure Levels%高收缩压水平脑分水岭梗死急性期升压治疗对预后影响的前瞻性研究

    Institute of Scientific and Technical Information of China (English)

    聂志余; 陈玉辉; 李艳成; 封亮; 潘有贵; 管强; 郭艳; 舒豪; 靳令经

    2015-01-01

    Objective To investigate the effect of elevated blood pressure(BP) on outcome of patients with acute cerebral watershed infarction(CWI) with systolic blood pressure(SBP) range from 140 to 160 mmHg. Methods Sixty-four successive patients with ifrst onset acute CWI with SBP range from 140 to 160 mmHg were enrolled in this prospective analysis, which was from department of neurology, Tongji hospital, Tongji University between January 2011 and November 2014. Patients were randomly divided into elevated BP treatment group(treatment group, 29 cases) and routine treatment group(routine group, 35 cases), Dopamine was given to elevate SBP about 20 mmHg in the treatment group besides routine ischemic stroke therapy including Aspirin and Atorvastatin etc. in the ifrst three days after admission. National Institutes of Health Stroke Scale(NIHSS) were recorded at admission and 2 weeks after admission or at discharge, modiifed Rankin Score(mRS) was collected for assessment of neurological function defect at 6 months after stroke. More than 46%decrease of NIHSS was deifned as effectivity of elevated BP treatment 2 weeks after admission or at discharge, and mRS≤2 was deifned as good outcome. Results There was no difference in baseline data including age, sex, disease time and NIHSS, etc. between two groups. The effective rate was 27.6%in treatment group and 28.6%in routine group 2 weeks after admission or at discharge. There was no statistic significance between two groups(P=0.930). The proportion of good outcome was higher in treatment group(65.5%) than in routine group(48.6%) at six months after stroke, but there was no statistic signiifcance(P=0.174). Conclusion Elevated BP treatment had no effect on obvious outcome in the patients with acute CWI with SBP ranged from 140 to 160 mmHg.%目的探讨升压治疗对收缩压(systolic blood pressure,SBP)在140~160 mmHg的急性脑分水岭梗死患者预后的影响。  方法本研究为

  15. Fluid responsiveness is predicted by analysis of extra systoles

    DEFF Research Database (Denmark)

    Vistisen, Simon Tilma

    INTRODUCTION. Fluid responsiveness prediction is an unsettled matter for intensive care patients. Preload variables are not reliable and ventilator settings for the vast majority of patients (if at all ventilated) do not accommodate the criteria for otherwise useful dynamic variables [1] (e.......g. pulse pressure variation). Yet, the idea of a varying preload utilised in dynamic variable monitoring may be useful: The extra systolic post-ectopic beat is associated with increased preload, and I hypothesised that systolic blood pressure (SBP) at the post-ectopic beat could be analysed in relation...... to surrounding sinus beats and that the magnitude of the SBP change (DSBP) could predict fluid responsiveness. OBJECTIVES. To study the hypothesis in post-cardiac surgery patients. METHODS. Patients scheduled for a 500 ml volume expansion were observed. In the time frame, 0-30 min prior to volume expansion, ECG...

  16. SLAPP: A systolic linear algebra parallel processor

    Energy Technology Data Exchange (ETDEWEB)

    Drake, B.L.; Luk, F.T.; Speiser, J.M.; Symanski, J.J. (Naval Ocean Systems Center and Cornell Univ.)

    1987-07-01

    Systolic array computer architectures provide a means for fast computation of the linear algebra algorithms that form the building blocks of many signal-processing algorithms, facilitating their real-time computation. For applications to signal processing, the systolic array operates on matrices, an inherently parallel view of the data, using numerical linear algebra algorithms that have been suitably parallelized to efficiently utilize the available hardware. This article describes work currently underway at the Naval Ocean Systems Center, San Diego, California, to build a two-dimensional systolic array, SLAPP, demonstrating efficient and modular parallelization of key matric computations for real-time signal- and image-processing problems.

  17. Hemodynamic Correlates of Late Systolic Flow Velocity Augmentation in the Carotid Artery

    OpenAIRE

    Heffernan, Kevin S.; Lefferts, Wesley K; Augustine, Jacqueline A.

    2013-01-01

    Background. The contour of the common carotid artery (CCA) blood flow velocity waveform changes with age; CCA flow velocity increases during late systole, and this may contribute to cerebrovascular disease. Late systolic flow velocity augmentation can be quantified using the flow augmentation index (FAIx). We examined hemodynamic correlates of FAIx to gain insight into determinants of CCA flow patterns. Methods. CCA Doppler ultrasound and wave intensity analysis (WIA) were used to assess regi...

  18. Systolic heart failure: A prothrombotic state

    NARCIS (Netherlands)

    De Peuter, Olav R.; Kok, Wouter E. M; Torp-Pedersen, Christian; Büller, Harry R.; Kamphuisen, Pieter W.

    2009-01-01

    Systolic heart failure is a common syndrome whose incidence is expected to increase. Several treatment modalities, such as -blockers and angiotensin-converting enzyme inhibitors, improve survival. Whether antithrombotic treatment is effective remains to be elucidated, although observations suggest a

  19. The changes of state-trait anxiety and blood plasma cortisol as well systolic pressure of armymen turned to sea training%部队转场海训后军人状态-特质焦虑与其收缩压和血皮质醇的变化

    Institute of Scientific and Technical Information of China (English)

    朱媛; 吴志颖; 付晓丽; 王丽杰

    2014-01-01

    Through investigating the state-trait anxiety of mental characteristics change of armymen in military activity,to provide the basis for early warning prevention. Methods Transition to sea training for the 15th day,state-trait anxiety based on a questionnaire of 420 people,and blood pressure,pulse rate and blood cortisol (08:00am-09:00am) were investigated and detected whose results were compared to the norm or the normal value. Results State anxiety was 2 values in 185 persons higher than the standard deviation of the norm, accounting for 44% of the total person-number. Trait anxiety values was 2 votes in 113 higher than the standard deviation of the norm (high trait anxiety), accounting for 26.9% of the total person-number, value of trait-anxiety was less than the standard deviation of the norm 2 votes(low trait anxiety) in 85 persons, accounting for 20.2% of the total number. Systolic blood pressure and cortisol changed significantly (P<0.01). State anxiety and serum cortisol and systolic blood pressure changed at the same time significantly in total person-number of 30.2%,but changes in diastolic blood pressure was not evident. Higher trait anxiety anxiety , blood cortisol and elevated systolic blood pressure in high trait anxiety persons were of 61.9%(70/113);state anxiety,elevated blood cortisol and systolic blood pressure were in 23.7% of the total number of non-higher trait anxiety persons (79/334),low trait anxiety of trait-anxiety were of 15% of total person-number(13/85). Conclusion Sea training is a stress event, trait anxiety refers to the relative stability,as personality trait anxiety tendency has individual differences. So coping anxiety active has military significance to physical and mental health and enhancing fighting capacity.%目的:通过调查状态-特质焦虑心理特质在军事活动中的变化,为预警预防提供依据。方法转场海训的第15天时,对420人进行状态-特质焦虑问卷、血

  20. Computational modeling of red blood cells: A symplectic integration algorithm

    Science.gov (United States)

    Schiller, Ulf D.; Ladd, Anthony J. C.

    2010-03-01

    Red blood cells can undergo shape transformations that impact the rheological properties of blood. Computational models have to account for the deformability and red blood cells are often modeled as elastically deformable objects. We present a symplectic integration algorithm for deformable objects. The surface is represented by a set of marker points obtained by surface triangulation, along with a set of fiber vectors that describe the orientation of the material plane. The various elastic energies are formulated in terms of these variables and the equations of motion are obtained by exact differentiation of a discretized Hamiltonian. The integration algorithm preserves the Hamiltonian structure and leads to highly accurate energy conservation, hence he method is expected to be more stable than conventional finite element methods. We apply the algorithm to simulate the shape dynamics of red blood cells.

  1. Mathematical modelling in blood coagulation : simulation and parameter estimation

    NARCIS (Netherlands)

    W.J.H. Stortelder (Walter); P.W. Hemker (Piet); H.C. Hemker

    1997-01-01

    textabstractThis paper describes the mathematical modelling of a part of the blood coagulation mechanism. The model includes the activation of factor X by a purified enzyme from Russel's Viper Venom (RVV), factor V and prothrombin, and also comprises the inactivation of the products formed. In this

  2. A VARIATIONAL MODEL FOR 2-D MICROPOLAR BLOOD FLOW

    Institute of Scientific and Technical Information of China (English)

    He Ji-huan

    2003-01-01

    The micropolar fluid model is an essential generalization of the well-established Navier-Stokes model in the sense that it takes into account the microstructure of the fluid.This paper is devolted to establishing a variational principle for 2-D incompressible micropolar blood flow.

  3. 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.

  4. Effect of Tamarindus indica fruits on blood pressure and lipid-profile in human model: an in vivo approach.

    Science.gov (United States)

    Iftekhar, A S M Maruf; Rayhan, Israt; Quadir, Mohiuddin Abdul; Akhteruzzaman, Sharif; Hasnat, Abul

    2006-04-01

    Fruits of Tamarindus indica were evaluated for their effects on lipid profile, systolic and diastolic blood pressure and body weight in human subjects. Dried and pulverized pulp of T. indica fruits, at a dose of 15 mg/kg body weight, was found to reduce total cholesterol level (p = 0.031) and LDL-cholesterol level (p = 0.004) to a significant extent. Though the fruits exerted no conspicuous effect on body weight and systolic blood pressure, it significantly reduced the diastolic pressure as confirmed by independent sample t-test at 5% significance level.

  5. Effects of Lead on Systolic and Diastolic Cardiac Functions

    Institute of Scientific and Technical Information of China (English)

    ZOUHE-JIAN; DINGYUE; 等

    1995-01-01

    In this paper,both systolic and diastolic cardiac functions were evaluated in 54 lead exposed and 24 non-exposed workers by Doppler echocardiography.With regard to systolic cardiac function,the results suggested that cardiac systolic function increased in exposed groups as a compensatory response for the effect of lead on myocardium.To study left ventricular diastolic function,2.5MHz pulsed Doppler analyses of transmitral flow velocity were performed from apical four-chamber view.The results showed that timerelated parameters were comparable among all groups,but blood flow velocity through the mitral valve and Doppler area fractions changed significantly in lead-exposed groups as evidenced by increased value A,decreased value E and E/A ratio.The decrease of diastolic cardiac function was more significant in lead intoxication group.It was also observed in this study that the activity in serum of the MB isoenzyme of creatine phosphokinase(CPK-MB),one of the indices of myocardial damage,was significantly higher in exposed group than that in control(P<0.05),and a positive correlation was found between CPK-MB activity and Pb-B.It denoted that the increasing of lead burden leads to more relase of CPK-MB from the myocardial cells and suggested the existence of slight myocardial damage,which conceivably,might cause harm to diastolic cardiac function.

  6. Contractility is the main determinant of coronary systolic flow impediment.

    Science.gov (United States)

    Krams, R; Sipkema, P; Zegers, J; Westerhof, N

    1989-12-01

    We measured the relation between coronary flow amplitude (delta F = Fd-Fs; where d is diastolic and s is systolic) and developed left ventricular pressure (delta PLV = Ps-Pd) at a constant perfusion pressure of 75 mmHg (10 kPa) in the maximally vasodilated blood-perfused isolated cat heart for different steady-state levels of contractility (protocol A) and during transients in contractility (protocol B). Contractility was defined as the slope of the end-systolic pressure-volume relation (Emax). From protocol A it appeared that the coronary flow amplitude was only weakly related to left ventricular pressure at each steady-state level of contractility studied. However, the coronary flow amplitude was strongly related to the different levels of contractility. In protocol B, contractility was changed over a wide range of values (0-100%) but developed pressure and contractility changed simultaneously. Using multiple linear regression analysis, we found that contractility has approximately 10 times (range: 2.8-57.3) stronger effect than left ventricular pressure on coronary flow amplitude (n = 10 experiments). These data and our earlier observations suggest that it is the difference in stiffness of cardiac muscle between systole and diastole that determines coronary flow amplitude.

  7. Spring-network-based model of a red blood cell for simulating mesoscopic blood flow.

    Science.gov (United States)

    Nakamura, Masanori; Bessho, Sadao; Wada, Shigeo

    2013-01-01

    We developed a mechanical model of a red blood cell (RBC) that is capable of expressing its characteristic behaviors in shear flows. The RBC was modeled as a closed shell membrane consisting of spring networks in the framework of the energy minimum concept. The fluid forces acting on RBCs were modeled from Newton's viscosity law and the conservation of momentum. In a steady shear flow, the RBC model exhibited various behaviors, depending on the shear rate; it tumbled, tank-treaded, or both. The transition from tumbling to tank-treading occurred at a shear rate of 20 s( - 1). The simulation of an RBC in steady and unsteady parallel shear flows (Couette flows) showed that the deformation parameters of the RBC were consistent with experimental results. The RBC in Poiseuille flow migrated radially towards the central axis of the flow channel. Axial migration became faster with an increase in the viscosity of the media, qualitatively consistent with experimental results. These results demonstrate that the proposed model satisfies the essential conditions for simulating RBC behavior in blood flow. Finally, a large-scale RBC flow simulation was implemented to show the capability of the proposed model for analyzing the mesoscopic nature of blood flow.

  8. Stochastic modeling for magnetic resonance quantification of myocardial blood flow

    Science.gov (United States)

    Seethamraju, Ravi T.; Muehling, Olaf; Panse, Prasad M.; Wilke, Norbert M.; Jerosch-Herold, Michael

    2000-10-01

    Quantification of myocardial blood flow is useful for determining the functional severity of coronary artery lesions. With advances in MR imaging it has become possible to assess myocardial perfusion and blood flow in a non-invasive manner by rapid serial imaging following injection of contrast agent. To date most approaches reported in the literature relied mostly on deriving relative indices of myocardial perfusion directly from the measured signal intensity curves. The central volume principle on the other hand states that it is possible to derive absolute myocardial blood flow from the tissue impulse response. Because of the sensitivity involved in deconvolution due to noise in measured data, conventional methods are sub-optimal, hence, we propose to use stochastic time series modeling techniques like ARMA to obtain a robust impulse response estimate. It is shown that these methods when applied for the optical estimation of the transfer function give accurate estimates of myocardial blood flow. The most significant advantage of this approach, compared with compartmental tracer kinetic models, is the use of a minimum set of prior assumptions on data. The bottleneck in assessing myocardial blood flow, does not lie in the MRI acquisition, but rather in the effort or time for post processing. It is anticipated that the very limited requirements for user input and interaction will be of significant advantage for the clinical application of these methods. The proposed methods are validated by comparison with mean blood flow measurements obtained from radio-isotope labeled microspheres.

  9. A novel transgenic zebrafish model for blood-brain and blood-retinal barrier development

    Directory of Open Access Journals (Sweden)

    Sugimoto Masahiko

    2010-07-01

    Full Text Available Abstract Background Development and maintenance of the blood-brain and blood-retinal barrier is critical for the homeostasis of brain and retinal tissue. Despite decades of research our knowledge of the formation and maintenance of the blood-brain (BBB and blood-retinal (BRB barrier is very limited. We have established an in vivo model to study the development and maintenance of these barriers by generating a transgenic zebrafish line that expresses a vitamin D-binding protein fused with enhanced green fluorescent protein (DBP-EGFP in blood plasma, as an endogenous tracer. Results The temporal establishment of the BBB and BRB was examined using this transgenic line and the results were compared with that obtained by injection of fluorescent dyes into the sinus venosus of embryos at various stages of development. We also examined the expression of claudin-5, a component of tight junctions during the first 4 days of development. We observed that the BBB of zebrafish starts to develop by 3 dpf, with expression of claudin-5 in the central arteries preceding it at 2 dpf. The hyaloid vasculature in the zebrafish retina develops a barrier function at 3 dpf, which endows the zebrafish with unique advantages for studying the BRB. Conclusion Zebrafish embryos develop BBB and BRB function simultaneously by 3 dpf, which is regulated by tight junction proteins. The Tg(l-fabp:DBP-EGFP zebrafish will have great advantages in studying development and maintenance of the blood-neural barrier, which is a new application for the widely used vertebrate model.

  10. Normalization effect of sports training on blood pressure in hypertensives.

    Science.gov (United States)

    Chen, Yi-Liang; Liu, Yuh-Feng; Huang, Chih-Yang; Lee, Shin-Da; Chan, Yi-Sheng; Chen, Chiu-Chou; Harris, Brennan; Kuo, Chia-Hua

    2010-02-01

    Exercise is recommended as a lifestyle intervention in preventing hypertension based on epidemiological findings. However, previous intervention studies have presented mixed results. This discrepancy could be associated with shortcomings related to sample sizes or the inclusion of normotensive participants. The aim of this prospective cohort study (N = 463) was to compare the chronic effect of increasing sports training time on resting blood pressure for normotensives and hypertensives. We assessed systolic blood pressure, diastolic blood pressure, body mass index (BMI), and homeostasis model assessment for insulin resistance (HOMA-IR) for 69 untreated hypertensive patients (age 20.6 +/- 0.1 years, systolic blood pressure >140 mmHg) and 394 normotensive controls (age 20.6 +/- 0.1 years) before training and at follow-up visits at 12 months. All participants enrolled in various sports training lessons for 8 hours a week. The baseline BMI and HOMA-IR in the hypertensive group were significantly higher than those in the control group. For the normotensive control group, no significant changes in systolic and diastolic blood pressure were observed after training. However, for the hypertensives, systolic and diastolic blood pressure were significantly reduced after training by approximately 15 mmHg and approximately 4 mmHg, respectively, and HOMA-IR was reduced by approximately 25%. In conclusion, the effect of sports training to lower blood pressure was confined to the group of hypertensives, which may account for the overall minimal reduction in blood pressure observed in previous intervention studies.

  11. A memory-based model for blood viscosity

    Science.gov (United States)

    Ionescu, Clara M.

    2017-04-01

    This paper presents a comparison between existing models for non-Newtonian fluid viscosity as a function of shear rate variations. A novel model is introduced whose parameters are linked to physiological phenomena in the blood. The end use of such models is to predict changes in viscosity to adapt the speed of a nanorobot device for targeted drug delivery purposes. Simulation results show the agreement between the proposed model and available models from literature. A laboratory scale validation of the proposed model for a fluid mimicking non-Newtonian properties has been performed. Conceptual perspectives are also given in this work.

  12. Blood

    Science.gov (United States)

    ... Also, blood is either Rh-positive or Rh-negative. So if you have type A blood, it's either A positive or A negative. Which type you are is important if you need a blood transfusion. And your Rh factor could be important ...

  13. Blood pressure, renal biochemical parameters and histopathology in an original rat model of essential hypertension (SHRSP/Kpo strain).

    Science.gov (United States)

    Kato, Takashi; Mizuguchi, Nobuyuki; Ito, Akihiko

    2015-01-01

    Hypertensive nephropathy, a consequence of chronic high blood pressure, is increasingly a cause of end-stage renal diseases and its correct management is very important for clinical outcome. Spontaneously hypertensive rat (SHR/Kpo) and stroke-prone SHR (SHRSP/Kpo) strains represent models of human essential hypertension. However, the kidney injuries in SHR/Kpo and SHRSP/Kpo are not well defined. We therefore characterized the renal pathophysiology of SHR/Kpo and SHRSP/Kpo compared with normotensive control (WKY/Kpo) rats. The SHRSP/Kpo exhibited increased systolic blood pressure at 10 weeks of age, and proteinuria and increased blood urea nitrogen (BUN) and serum creatinine levels at 20 weeks. We simultaneously detected mononuclear cell infiltration, tubular injuries, accumulation of extracellular matrix and marked expression of α-SMA in the tubulointerstitium. Additionally, TGF-β1 and CTGF were up-regulated in the kidney of SHRSP/Kpo. We lastly focused on changes in glomerular cells of SHRSP/Kpo. Nestin, a podocyte marker, was detected but decreased slightly in 20-week-old SHRSP/Kpo. PECAM-1 expression was increased in SHRSP/Kpo glomeruli, indicating the thickening of glomerular endothelial cells. Moreover, we found that α-SMA, a myofibroblast marker, was also upregulated in the glomeruli of SHRSP/Kpo at 20 weeks. These findings suggest that SHRSP/Kpo could be a valuable animal model for human hypertensive nephropathy.

  14. [Cardiovascular risk stratification. Systolic, diastolic or pulse pressure?].

    Science.gov (United States)

    Pede, S; Lombardo, M

    2001-04-01

    It is well known that hypertension is a highly prevalent condition in the population, carries a significant risk of adverse cardiovascular events and is therapeutically difficult to control. These factors render it "a major unsolved - but soluble - mass public health problem". One of the present-day aspects of the complexity of managing patients with high blood pressure (BP) derives from clinical and epidemiological data that have emerged over the past 10 years: the growing importance of the clinical significance of systolic and pulse BP. The pathophysiological basis of these data is based, on the one hand, on a better articulated definition of the components of BP, and on the other, on precise information concerning age-related modifications. The common definition of BP does not take into account pressure fluctuations occurring during the cardiac cycle; in fact, systolic and diastolic BP denote the extreme values of continuous variations in differential pressure. Diastolic BP reflects, to a greater extent, the trend of arterial resistances and mean BP (usually calculated as diastolic BP plus one third of the differential BP, and considered the "stable component" of the arterial sphygmogram) and has long been used as a diagnostic and therapeutic target. Systolic BP is more closely linked to variations in pulse BP (given from the difference between systolic and diastolic BP and considered the "dynamic component" of the arterial sphygmogram) and is produced by a group of factors including left ventricular ejection and the reflection of the sphygmic wave. As age increases, the walls of the aorta and the large elastic arteries progressively harden due to senile degenerative phenomena and the loss of elasticity as well as the progressive diffusion of atherosdclerotic lesions. This leads to the reduced capacity of the arterial wall to distend during the systole with a consequent increase in both systolic and pulse BP. These pathophysiological data have important clinical

  15. A data driven nonlinear stochastic model for blood glucose dynamics.

    Science.gov (United States)

    Zhang, Yan; Holt, Tim A; Khovanova, Natalia

    2016-03-01

    The development of adequate mathematical models for blood glucose dynamics may improve early diagnosis and control of diabetes mellitus (DM). We have developed a stochastic nonlinear second order differential equation to describe the response of blood glucose concentration to food intake using continuous glucose monitoring (CGM) data. A variational Bayesian learning scheme was applied to define the number and values of the system's parameters by iterative optimisation of free energy. The model has the minimal order and number of parameters to successfully describe blood glucose dynamics in people with and without DM. The model accounts for the nonlinearity and stochasticity of the underlying glucose-insulin dynamic process. Being data-driven, it takes full advantage of available CGM data and, at the same time, reflects the intrinsic characteristics of the glucose-insulin system without detailed knowledge of the physiological mechanisms. We have shown that the dynamics of some postprandial blood glucose excursions can be described by a reduced (linear) model, previously seen in the literature. A comprehensive analysis demonstrates that deterministic system parameters belong to different ranges for diabetes and controls. Implications for clinical practice are discussed. This is the first study introducing a continuous data-driven nonlinear stochastic model capable of describing both DM and non-DM profiles.

  16. Using extra systoles to predict fluid responsiveness in cardiothoracic critical care patients.

    Science.gov (United States)

    Vistisen, Simon Tilma

    2017-08-01

    Fluid responsiveness prediction is an unsettled matter for most critical care patients and new methods relying only on the continuous basic monitoring are desired. It was hypothesized that the post-ectopic beat, which is associated with increased preload, could be analyzed in relation to preceding sinus beats and that the change in cardiac performance (e.g. systolic blood pressure) at the post-ectopic beat could predict fluid responsiveness. Cardiothoracic critical care patients scheduled for a 500 ml volume expansion were observed. In the 30 min prior to volume expansion, the ECG was analyzed for occurrence of extra systoles preceded by at least 10 sinus beats. Classification variables, were defined as the change in a variable (e.g. systolic blood pressure or pre-ejection period) from the median of 10 preceding sinus beats to extra systolic post-ectopic beat. A stroke volume increase >15 % following volume expansion defined fluid responsiveness. Thirty patients were included. The change in systolic blood pressure predicted fluid responsiveness in 24 patients correctly with 83 % specificity and 75 % sensitivity (optimal threshold: 5 % systolic blood pressure increase), receiver operating characteristic (ROC) area: 0.81 (CI [0.64;0.98]). The change in pre-ejection period predicted fluid responsiveness in 22 patients correctly with 67 % specificity and 83 % sensitivity (optimal threshold: 19 ms pre-ejection period decrease), ROC area: 0.81 (CI [0.66;0.96]). Pulse pressure variation had ROC area of 0.57 (CI [0.39;0.75]). Based on standard critical care monitoring, analysis of the extra systolic post-ectopic beat predicts fluid responsiveness in cardiothoracic critical care patients with good accuracy.

  17. Seamless particle-based modeling of blood clotting

    Science.gov (United States)

    Yazdani, Alireza; Karniadakis, George

    2016-11-01

    We propose a new multiscale framework that seamlessly integrate four key components of blood clotting namely, blood rheology, cell mechanics, coagulation kinetics and transport of species and platelet adhesive dynamics. We use transport dissipative particle dynamics (tDPD) which is an extended form of original DPD as the base solver to model both blood flow and the reactive transport of chemical species in the coagulation cascade. Further, we use a coarse-grained representation of blood cell's membrane that accounts for its mechanics; both red blood cells and platelets are resolved at sub-cellular resolution, and stochastic bond formation/dissociation are included to account for platelet adhesive dynamics at the site of injury. Our results show good qualitative agreement with in vivo experiments. The numerical framework allows us to perform systematic analysis on different mechanisms of blood clotting. In addition, this new multiscale particle-based methodology can open new directions in addressing different biological processes from sub-cellular to macroscopic scales. NIH Grant No. U01HL116323.

  18. [A Nude Mouse Model for Human Umbilical Cord Blood Transplantation

    Science.gov (United States)

    Lan, Jiongcai; Liu, Hongyu; Chen, Qiang; Yang, Chongli; Zhang, Zhimei

    2000-03-01

    To evaluate the hematopoietic potentiality and the migration and homing routine of separated as well as cryopreserved umbilical cord blood hematopoietic cells, the BALB/cnu(+) mice were used to establish a murine model. This can prepare for the clinical transplantation and the establishment of a large-scale cord blood bank. The result indicated that the hydroxyethyl starch (HES) sedimentation and DMSO step-by-step cryopreservation procedure resulted in only less losses of hematopoietic progenitor cells and also unharmful to the hematopietic potentiality. We can found evidence for successful transplantation in each mouse which received (1.0 - 2.0) x 10(7) separated or cryopresered hematopoietic cells from cord blood, which lasted for about fifty days. The results demonstrated that (1) HES sedimentation and DMSO cryopreservation procedure can keep the hematopoietic potentiality of cord blood, and so can be used to clinical transplantation or establishment of a cord blood bank; (2) Rich hematopoietic stem cells in human cord blood can cross the xenogenetic barriers and successfully engraft mice; (3) The hematopoietic cells migrated among bone marrow, liver, spleen, lung and kidney in the mice and homed to bone marrow by the end. Cryopreservation may influence the adhesion molecule on the hematopoietic cells and the homing behaviour, but not influence their hematopoietic potentiality.

  19. QSAR model for blood-brain barrier permeation.

    Science.gov (United States)

    Toropov, Andrey A; Toropova, Alla P; Beeg, Marten; Gobbi, Marco; Salmona, Mario

    2017-05-02

    Predicting blood-brain barrier permeability for novel compounds is an important goal for neurotherapeutics-focused drug discovery. It is impossible to determine experimentally the blood-brain barrier partitioning of all possible candidates. Consequently, alternative evaluation methods based on computational models are desirable or even necessary. The CORAL software (http://www.insilico.eu/coral) has been checked up as a tool to build up quantitative structure - activity relationships for blood-brain barrier permeation. The Monte Carlo technique gives possibility to build up predictive model of an endpoint by means of selection of so-called correlation weights of various molecular features. Descriptors calculated with these weights are basis for correlations "structure-endpoint". The approach gives good models for three random splits into the training and validation sets. The best model characterized by the following statistics for the external validation set: the number of compounds is 41, determination coefficient is equal to 0.896, root mean squared error is equal to 0.175. The suggested approach can be applied as a tool for prediction of blood-brain barrier permeation. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Multiscale modeling of red blood cell mechanics and blood flow in malaria.

    Directory of Open Access Journals (Sweden)

    Dmitry A Fedosov

    2011-12-01

    Full Text Available Red blood cells (RBCs infected by a Plasmodium parasite in malaria may lose their membrane deformability with a relative membrane stiffening more than ten-fold in comparison with healthy RBCs leading to potential capillary occlusions. Moreover, infected RBCs are able to adhere to other healthy and parasitized cells and to the vascular endothelium resulting in a substantial disruption of normal blood circulation. In the present work, we simulate infected RBCs in malaria using a multiscale RBC model based on the dissipative particle dynamics method, coupling scales at the sub-cellular level with scales at the vessel size. Our objective is to conduct a full validation of the RBC model with a diverse set of experimental data, including temperature dependence, and to identify the limitations of this purely mechanistic model. The simulated elastic deformations of parasitized RBCs match those obtained in optical-tweezers experiments for different stages of intra-erythrocytic parasite development. The rheological properties of RBCs in malaria are compared with those obtained by optical magnetic twisting cytometry and by monitoring membrane fluctuations at room, physiological, and febrile temperatures. We also study the dynamics of infected RBCs in Poiseuille flow in comparison with healthy cells and present validated bulk viscosity predictions of malaria-infected blood for a wide range of parasitemia levels (percentage of infected RBCs with respect to the total number of cells in a unit volume.

  1. 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.

  2. Evaluation of a murine single-blood-injection SAH model.

    Directory of Open Access Journals (Sweden)

    Marcel A Kamp

    Full Text Available The molecular pathways underlying the pathogenesis after subarachnoid haemorrhage (SAH are poorly understood and continue to be a matter of debate. A valid murine SAH injection model is not yet available but would be the prerequisite for further transgenic studies assessing the mechanisms following SAH. Using the murine single injection model, we examined the effects of SAH on regional cerebral blood flow (rCBF in the somatosensory (S1 and cerebellar cortex, neuro-behavioural and morphological integrity and changes in quantitative electrocorticographic and electrocardiographic parameters. Micro CT imaging verified successful blood delivery into the cisterna magna. An acute impairment of rCBF was observed immediately after injection in the SAH and after 6, 12 and 24 hours in the S1 and 6 and 12 hours after SAH in the cerebellum. Injection of blood into the foramen magnum reduced telemetric recorded total ECoG power by an average of 65%. Spectral analysis of ECoGs revealed significantly increased absolute delta power, i.e., slowing, cortical depolarisations and changes in ripples and fast ripple oscillations 12 hours and 24 hours after SAH. Therefore, murine single-blood-injection SAH model is suitable for pathophysiological and further molecular analysis following SAH.

  3. Wafer-Scale Integration of Systolic Arrays,

    Science.gov (United States)

    1985-10-01

    wafer-scale system, however, all the nearest neighbors of a processor may be dead, and thus the prime advantage of adopting a systolic array...work, however. To the best of our knowledge, the only result of a similar nature is due to Erdos and Renyi 15] who showed that most graphs with N

  4. Lack of reproducibility of linkage results in serially measured blood pressure data

    NARCIS (Netherlands)

    Patel, [No Value; Celedon, JC; Weiss, ST; Palmer, LJ

    2003-01-01

    Background: Using the longitudinal Framingham Heart Study data on blood pressure, we analyzed the reproducibility of linkage measures from serial cross-sectional surveys of a defined population by performing genome-wide model-free linkage analyses to systolic blood pressure (SBP) and history of hype

  5. Blood pressure and blood flow variation during postural change from sitting to standing: model development and validation

    DEFF Research Database (Denmark)

    Olufsen, M.S.; Ottesen, Johnny T.; Tran, H.T.

    2005-01-01

    dynamic changes in beat-to-beat arterial blood pressure and middle cerebral artery blood flow velocity during postural change from sitting to standing. Our cardiovascular model utilizes 11 compartments to describe blood pressure, blood flow, compliance, and resistance in the heart and systemic circulation....... To include dynamics due to the pulsatile nature of blood pressure and blood flow, resistances in the large systemic arteries are modeled using nonlinear functions of pressure. A physiologically based submodel is used to describe effects of gravity on venous blood pooling during postural change. Two types...... of control mechanisms are included: 1) autonomic regulation mediated by sympathetic and parasympathetic responses, which affect heart rate, cardiac contractility, resistance, and compliance, and 2) autoregulation mediated by responses to local changes in myogenic tone, metabolic demand, and CO2 concentration...

  6. General coarse-grained red blood cell models: I. Mechanics

    OpenAIRE

    FEDOSOV, DMITRY A.; Caswell, Bruce; Karniadakis, George E.

    2009-01-01

    We present a rigorous procedure to derive coarse-grained red blood cell (RBC) models, which lead to accurate mechanical properties of realistic RBCs. Based on a semi-analytic theory linear and non-linear elastic properties of the RBC membrane can be matched with those obtained in optical tweezers stretching experiments. In addition, we develop a nearly stress-free model which avoids a number of pitfalls of existing RBC models, such as non-biconcave equilibrium shape and dependence of RBC mech...

  7. Associations of ambulatory blood pressure with urinary caffeine and caffeine metabolite excretions.

    Science.gov (United States)

    Guessous, Idris; Pruijm, Menno; Ponte, Belén; Ackermann, Daniel; Ehret, Georg; Ansermot, Nicolas; Vuistiner, Philippe; Staessen, Jan; Gu, Yumei; Paccaud, Fred; Mohaupt, Markus; Vogt, Bruno; Pechère-Bertschi, Antoinette; Pechère-Berstchi, Antoinette; Martin, Pierre-Yves; Burnier, Michel; Eap, Chin B; Bochud, Murielle

    2015-03-01

    Intake of caffeinated beverages might be associated with reduced cardiovascular mortality possibly via the lowering of blood pressure. We estimated the association of ambulatory blood pressure with urinary caffeine and caffeine metabolites in a population-based sample. Families were randomly selected from the general population of Swiss cities. Ambulatory blood pressure monitoring was conducted using validated devices. Urinary caffeine, paraxanthine, theophylline, and theobromine excretions were measured in 24 hours urine using ultrahigh performance liquid chromatography tandem mass spectrometry. We used mixed models to explore the associations of urinary excretions with blood pressure although adjusting for major confounders. The 836 participants (48.9% men) included in this analysis had mean age of 47.8 and mean 24-hour systolic and diastolic blood pressure of 120.1 and 78.0 mm Hg. For each doubling of caffeine excretion, 24-hour and night-time systolic blood pressure decreased by 0.642 and 1.107 mm Hg (both P values theobromine excretion was not associated with blood pressure. Anti-hypertensive therapy, diabetes mellitus, and alcohol consumption modify the association of caffeine urinary excretion with systolic blood pressure. Ambulatory systolic blood pressure was inversely associated with urinary excretions of caffeine and other caffeine metabolites. Our results are compatible with a potential protective effect of caffeine on blood pressure.

  8. A dynamic model of renal blood flow autoregulation

    DEFF Research Database (Denmark)

    Holstein-Rathlou, N H; Marsh, D J

    1994-01-01

    To test whether a mathematical model combining dynamic models of the tubuloglomerular feedback (TGF) mechanism and the myogenic mechanism was sufficient to explain dynamic autoregulation of renal blood flow, we compared model simulations with experimental data. To assess the dynamic characteristics...... nephrons act in parallel, each simulation was performed with 125 parallel versions of the model. The key parameters of the 125 versions of the model were chosen randomly within the physiological range. None of the constituent models, i.e., the TGF and the myogenic, could alone reproduce the experimental...... observations. However, in combination they reproduced most of hte features of the various transfer functions calculated from the experimental data. The major discrepancy was the presence of a bimodal distribution of the admittance phase in the simulations. This is not consistent with most of the experimental...

  9. Novel models for studying the blood-brain and blood-eye barriers in Drosophila.

    Science.gov (United States)

    Pinsonneault, Robert L; Mayer, Nasima; Mayer, Fahima; Tegegn, Nebiyu; Bainton, Roland J

    2011-01-01

    In species as varied as humans and flies, humoral/central nervous system barrier structures are a major obstacle to the passive penetration of small molecules including endogenous compounds, environmental toxins, and drugs. In vivo measurement of blood-brain physiologic function in vertebrate animal models is difficult and current ex vivo models for more rapid experimentation using, for example, cultured brain endothelial cells, only partially reconstitute the anatomy and physiology of a fully intact blood-brain barrier (BBB). To address these problems, we and others continue to develop in vivo assays for studying the complex physiologic function of central nervous system (CNS) barriers using the fruit fly Drosophila melanogaster (Dm). These methods involve the introduction of small molecule reporters of BBB physiology into the fly humoral compartment by direct injection. Since these reporters must cross the Dm BBB in order to be visible in the eye, we can directly assess genetic or chemical modulators of BBB function by monitoring retinal fluorescence. This assay has the advantage of utilizing a physiologically intact BBB in a model organism that is economical and highly amenable to genetic manipulation. In combination with other approaches outlined here, such as brain dissection and behavioral assessment, one can produce a fuller picture of BBB biology and physiology. In this chapter, we provide detailed methods for examining BBB biology in the fly, including a Dm visual assay to screen for novel modulators of the BBB.

  10. 2-D Model for Normal and Sickle Cell Blood Microcirculation

    Science.gov (United States)

    Tekleab, Yonatan; Harris, Wesley

    2011-11-01

    Sickle cell disease (SCD) is a genetic disorder that alters the red blood cell (RBC) structure and function such that hemoglobin (Hb) cannot effectively bind and release oxygen. Previous computational models have been designed to study the microcirculation for insight into blood disorders such as SCD. Our novel 2-D computational model represents a fast, time efficient method developed to analyze flow dynamics, O2 diffusion, and cell deformation in the microcirculation. The model uses a finite difference, Crank-Nicholson scheme to compute the flow and O2 concentration, and the level set computational method to advect the RBC membrane on a staggered grid. Several sets of initial and boundary conditions were tested. Simulation data indicate a few parameters to be significant in the perturbation of the blood flow and O2 concentration profiles. Specifically, the Hill coefficient, arterial O2 partial pressure, O2 partial pressure at 50% Hb saturation, and cell membrane stiffness are significant factors. Results were found to be consistent with those of Le Floch [2010] and Secomb [2006].

  11. Dynamic characteristics and mechatronics model for maglev blood pump

    Science.gov (United States)

    Sun, Kun; Chen, Chen

    2017-01-01

    Magnetic bearing system(MBs) has been developed in the new-generation blood pump due to its low power consumption, low blood trauma and high durability. However, MBs for a blood pump were almost influenced by a series of factors such as hemodynamics, rotation speeds and actuator response in working fluids, compared with those applied in other industrial fields. In this study, the dynamic characteristics of MBs in fluid environments, including the influence of the pumping fluid and rotation of the impeller on the radial dynamic model were investigated by measuring the frequency response to sinusoidal excitation upon coils, and the response of radial displacement during a raise in the speed. The excitation tests were conducted under conditions in which the blood pump was levitated in air and water and with or without rotation. The experimental and simulated results indicate that rotations of the impeller affected the characteristics of MBs in water apparently, and the vibration in water was decreased, compared with that in air due to the hydraulic force. During the start-up and rotation, the actuator failed to operate fully and timely, and the voltage supplied can be chosen under the consideration of the rotor displacement and consumption.

  12. Effects of age and gender on the circadian rhythm of systolic blood pressure and endothelial vasoactive substances in the rat%年龄与性别对大鼠收缩压和内皮源性血管活性物质昼夜节律的影响

    Institute of Scientific and Technical Information of China (English)

    尹广利; 郭艺芳; 刘梅; 赵晓云; 姚丽霞; 国雪; 王智华

    2012-01-01

    ) is unknown. Objective To investigate the circadian rhythm of systolic blood pressure and endothelial vasoactive substances in the rats of different age and gender. Methods One hundred and twenty-eight SD rats were divided into four groups: 1Adult male rats (10 weeks old), 2Adult female rats (10 weeks old). 3Older male rats (96 weeks old). 4Older female rats(96 weeks old). Rats were killed every 6 hours (at 2:00, 8:00, 14 :00 and 20:00, respectively) by decapitation after systolic blood pressures(SBP) were measured. Plasma NO was measured by nitrate reductasc technique. The level of plasma ET-1 was measured by radioimmunoassay. Results (D SBP were markedly higher in older rats than in audit rats(P 0. 05), but the levels of plasma ET 1 and NO were lower(P<0. 05). (DSBP and endothclial vasoactive substances of four groups all showed the chronobiological features. There exists a difference in SBP peak phase between adult and older rats, also between adult male and female rats. However there was no difference between older male and female rats. The peak phase of endothelial vasoactive substances in every group showed significant shift. Conclusion Age and gender have impact on the chronobiological indices of systolic blood pressures and plasma ET-1 and NO.

  13. Hyperellipticity and Systoles of Klein Surfaces

    CERN Document Server

    Katz, Mikhail G

    2012-01-01

    Given a hyperelliptic Klein surface, we construct companion Klein bottles, extending our technique of companion tori already exploited by the authors in the genus 2 case. Bavard's short loops on such companion surfaces are studied in relation to the original surface so to improve a systolic inequality of Gromov's. A basic idea is to use length bounds for loops on a companion Klein bottle, and then analyze how curves transplant to the original nonorientable surface. We exploit the real structure on the orientable double cover by applying the coarea inequality to the distance function from the real locus. Of particular interest is the case of Dyck's surface. We also exploit an optimal systolic bound for the M\\"obius band, due to Blatter.

  14. Multiscale Modeling of Red Blood Cells Squeezing through Submicron Slits

    Science.gov (United States)

    Peng, Zhangli; Lu, Huijie

    2016-11-01

    A multiscale model is applied to study the dynamics of healthy red blood cells (RBCs), RBCs in hereditary spherocytosis, and sickle cell disease squeezing through submicron slits. This study is motivated by the mechanical filtration of RBCs by inter-endothelial slits in the spleen. First, the model is validated by comparing the simulation results with experiments. Secondly, the deformation of the cytoskeleton in healthy RBCs is investigated. Thirdly, the mechanisms of damage in hereditary spherocytosis are investigated. Finally, the effects of cytoplasm and membrane viscosities, especially in sickle cell disease, are examined. The simulations results provided guidance for future experiments to explore the dynamics of RBCs under extreme deformation.

  15. Systolic heart failure: a prothrombotic state

    DEFF Research Database (Denmark)

    de Peuter, Olav R; Kok, Wouter E M; Torp-Pedersen, Christian

    2009-01-01

    Systolic heart failure is a common syndrome whose incidence is expected to increase. Several treatment modalities, such as beta-blockers and angiotensin-converting enzyme inhibitors, improve survival. Whether antithrombotic treatment is effective remains to be elucidated, although observations...... suggest a prothrombotic state in heart failure. This article focuses on this prothrombotic state and discusses the risk of thromboembolic events, pathophysiological mechanisms, and the potential role of anticoagulant treatment....

  16. Systolic Time Intervals and New Measurement Methods.

    Science.gov (United States)

    Tavakolian, Kouhyar

    2016-06-01

    Systolic time intervals have been used to detect and quantify the directional changes of left ventricular function. New methods of recording these cardiac timings, which are less cumbersome, have been recently developed and this has created a renewed interest and novel applications for these cardiac timings. This manuscript reviews these new methods and addresses the potential for the application of these cardiac timings for the diagnosis and prognosis of different cardiac diseases.

  17. The effect of regular aquatic exercise on blood pressure: A meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Igarashi, Yutaka; Nogami, Yoshie

    2017-01-01

    Background No meta-analysis has examined the effect of regular aquatic exercise on blood pressure. The purpose of this study was to perform a meta-analysis to evaluate the effects of regular aquatic exercise on blood pressure. Design A meta-analysis of randomized controlled trials. Methods Databases were searched for literature published up to April 2017. The randomized controlled trials analysed involved healthy adults, an intervention group that only performed aquatic exercise and a control group that did not exercise, no other intervention, and trials indicated mean systolic blood pressure or diastolic blood pressure. The net change in blood pressure was calculated from each trial, and the changes in blood pressure were pooled by a random effects model, and the risk of heterogeneity was evaluated. Subgroup analysis of subjects with hypertension, subjects who performed endurance exercise (or not), and subjects who only swam (or not) was performed, and the net changes in blood pressure were pooled. Results The meta-analysis examined 14 trials involving 452 subjects. Pooled net changes in blood pressure improved significantly (systolic blood pressure -8.4 mmHg; diastolic blood pressure -3.3 mmHg) and the changes in systolic blood pressure contained significant heterogeneity. When subjects were limited to those with hypertension, those who performed endurance exercise and subjects who did not swim, pooled net changes in systolic and diastolic blood pressure decreased significantly, but the heterogeneity of systolic blood pressure did not improve. Conclusion Like exercise on land, aquatic exercise should have a beneficial effect by lowering blood pressure. In addition, aquatic exercise should lower the blood pressure of subjects with hypertension, and other forms of aquatic exercise besides swimming should also lower blood pressure.

  18. A model of blood flow in the mesenteric arterial system

    Directory of Open Access Journals (Sweden)

    Cheng Leo K

    2007-05-01

    Full Text Available Abstract Background There are some early clinical indicators of cardiac ischemia, most notably a change in a person's electrocardiogram. Less well understood, but potentially just as dangerous, is ischemia that develops in the gastrointestinal system. Such ischemia is difficult to diagnose without angiography (an invasive and time-consuming procedure mainly due to the highly unspecific nature of the disease. Understanding how perfusion is affected during ischemic conditions can be a useful clinical tool which can help clinicians during the diagnosis process. As a first step towards this final goal, a computational model of the gastrointestinal system has been developed and used to simulate realistic blood flow during normal conditions. Methods An anatomically and biophysically based model of the major mesenteric arteries has been developed to be used to simulate normal blood flows. The computational mesh used for the simulations has been generated using data from the Visible Human project. The 3D Navier-Stokes equations that govern flow within this mesh have been simplified to an efficient 1D scheme. This scheme, together with a constitutive pressure-radius relationship, has been solved numerically for pressure, vessel radius and velocity for the entire mesenteric arterial network. Results The computational model developed shows close agreement with physiologically realistic geometries other researchers have recorded in vivo. Using this model as a framework, results were analyzed for the four distinct phases of the cardiac cycle – diastole, isovolumic contraction, ejection and isovolumic relaxation. Profiles showing the temporally varying pressure and velocity for a periodic input varying between 10.2 kPa (77 mmHg and 14.6 kPa (110 mmHg at the abdominal aorta are presented. An analytical solution has been developed to model blood flow in tapering vessels and when compared with the numerical solution, showed excellent agreement. Conclusion An

  19. Blood flow in the cerebral venous system: modeling and simulation.

    Science.gov (United States)

    Miraucourt, Olivia; Salmon, Stéphanie; Szopos, Marcela; Thiriet, Marc

    2017-04-01

    The development of a software platform incorporating all aspects, from medical imaging data, through three-dimensional reconstruction and suitable meshing, up to simulation of blood flow in patient-specific geometries, is a crucial challenge in biomedical engineering. In the present study, a fully three-dimensional blood flow simulation is carried out through a complete rigid macrovascular circuit, namely the intracranial venous network, instead of a reduced order simulation and partial vascular network. The biomechanical modeling step is carefully analyzed and leads to the description of the flow governed by the dimensionless Navier-Stokes equations for an incompressible viscous fluid. The equations are then numerically solved with a free finite element software using five meshes of a realistic geometry obtained from medical images to prove the feasibility of the pipeline. Some features of the intracranial venous circuit in the supine position such as asymmetric behavior in merging regions are discussed.

  20. Mathematical modelling of blood-brain barrier failure and edema

    Science.gov (United States)

    Waters, Sarah; Lang, Georgina; Vella, Dominic; Goriely, Alain

    2015-11-01

    Injuries such as traumatic brain injury and stroke can result in increased blood-brain barrier permeability. This increase may lead to water accumulation in the brain tissue resulting in vasogenic edema. Although the initial injury may be localised, the resulting edema causes mechanical damage and compression of the vasculature beyond the original injury site. We employ a biphasic mixture model to investigate the consequences of blood-brain barrier permeability changes within a region of brain tissue and the onset of vasogenic edema. We find that such localised changes can indeed result in brain tissue swelling and that the type of damage that results (stress damage or strain damage) depends on the ability of the brain to clear edema fluid.

  1. Significance of white-coat hypertension in older persons with isolated systolic hypertension

    DEFF Research Database (Denmark)

    Franklin, Stanley S; Thijs, Lutgarde; Hansen, Tine W;

    2012-01-01

    The significance of white-coat hypertension in older persons with isolated systolic hypertension remains poorly understood. We analyzed subjects from the population-based 11-country International Database on Ambulatory Blood Pressure Monitoring in Relation to Cardiovascular Outcomes database who...... had daytime ambulatory blood pressure (BP; ABP) and conventional BP (CBP) measurements. After excluding persons with diastolic hypertension by CBP (=90 mm Hg) or by daytime ABP (=85 mm Hg), a history of cardiovascular disease, and persons...

  2. A robust optimization model for blood supply chain in emergency situations

    OpenAIRE

    Meysam Fereiduni; Kamran Shahanaghi

    2016-01-01

    In this paper, a multi-period model for blood supply chain in emergency situation is presented to optimize decisions related to locate blood facilities and distribute blood products after natural disasters. In disastrous situations, uncertainty is an inseparable part of humanitarian logistics and blood supply chain as well. This paper proposes a robust network to capture the uncertain nature of blood supply chain during and after disasters. This study considers donor points, blood facilities,...

  3. Multiscale modeling and simulation of brain blood flow

    Energy Technology Data Exchange (ETDEWEB)

    Perdikaris, Paris, E-mail: parisp@mit.edu [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Grinberg, Leopold, E-mail: leopoldgrinberg@us.ibm.com [IBM T.J Watson Research Center, 1 Rogers St, Cambridge, Massachusetts 02142 (United States); Karniadakis, George Em, E-mail: george-karniadakis@brown.edu [Division of Applied Mathematics, Brown University, Providence, Rhode Island 02912 (United States)

    2016-02-15

    The aim of this work is to present an overview of recent advances in multi-scale modeling of brain blood flow. In particular, we present some approaches that enable the in silico study of multi-scale and multi-physics phenomena in the cerebral vasculature. We discuss the formulation of continuum and atomistic modeling approaches, present a consistent framework for their concurrent coupling, and list some of the challenges that one needs to overcome in achieving a seamless and scalable integration of heterogeneous numerical solvers. The effectiveness of the proposed framework is demonstrated in a realistic case involving modeling the thrombus formation process taking place on the wall of a patient-specific cerebral aneurysm. This highlights the ability of multi-scale algorithms to resolve important biophysical processes that span several spatial and temporal scales, potentially yielding new insight into the key aspects of brain blood flow in health and disease. Finally, we discuss open questions in multi-scale modeling and emerging topics of future research.

  4. Life course structural equation model of the effects of prenatal and postnatal growth on adult blood pressure.

    Science.gov (United States)

    Kaakinen, Marika; Sovio, Ulla; Hartikainen, Anna-Liisa; Pouta, Anneli; Savolainen, Markku J; Herzig, Karl-Heinz; Elliott, Paul; De Stavola, Bianca; Läärä, Esa; Järvelin, Marjo-Riitta

    2014-12-01

    Fetal and postnatal growth have been associated with adult blood pressure (BP), but findings about the relative importance of growth at different stages of life on BP are inconsistent. The study population comprised 5198 participants from the Northern Finland Birth Cohort 1966 with data on birth weight, height and weight measurements until adolescence, systolic and diastolic BP at 31 years and several covariates. Structural equation modelling was used in the analysis. Negative direct effects of birth weight on adult systolic BP were observed (standardised regression coefficients: -0.08 (-0.14 to -0.03) in males and -0.04 (-0.09 to 0.01) in females, equalling -1.99 (-3.32 to -0.65) and -1.01 (-2.33 to 0.32) mm Hg/kg, respectively). Immediate postnatal growth was associated with adult BP only indirectly via growth later in life. In contrast, growth from adiposity rebound onwards had large direct, indirect and total effects on adult BP. Current body mass index was the strongest growth-related predictor of adult BP (0.36 (0.30 to 0.41) in males and 0.31 (0.24, 0.37) in females, equalling 1.29 (1.09 to 1.48) and 0.81 (0.63 to 0.99) mm Hg/(kg/m(2)), respectively). Our path analytical approach provides evidence for the importance of both fetal growth and postnatal growth, especially from adiposity rebound onwards, in determining adult BP, together with genetic predisposition and behavioural factors. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  5. Eplerenone in Patients with Systolic Heart Failure and Mild Symptoms.

    NARCIS (Netherlands)

    Zannad, Faiez; McMurray, John J. V.; Krum, Henry; van Veldhuisen, Dirk J.; Swedberg, Karl; Shi, Harry; Vincent, John; Pocock, Stuart J.; Pitt, Bertram

    2011-01-01

    Background: Mineralocorticoid antagonists improve survival among patients with chronic, severe systolic heart failure and heart failure after myocardial infarction. We evaluated the effects of eplerenone in patients with chronic systolic heart failure and mild symptoms. Methods: In this randomized,

  6. Mitral annular systolic velocity as a marker of preclinical systolic dysfunction among patients with arterial hypertension

    Directory of Open Access Journals (Sweden)

    Daskalov Ivaylo Rilkov

    2012-11-01

    Full Text Available Abstract Background The aim of this study was to investigate early changes in left ventricular longitudinal systolic function in patients with hypertension (HTN with and without concomitant diastolic dysfunction (DD and the clinical implications of these findings. Method We enrolled 299 patients with HTN and 297 age-matched patients with HTN and DD and compared both groups with an age-matched control group consisting of 100 healthy subjects. The long axis systolic function was investigated by determining the average peak systolic velocity of the septal and lateral mitral sites (Smavg using spectral pulsed wave tissue Doppler imaging (TDI. Results We found a strong negative trend toward the reduction of velocity, which is dependent on the grade of HTN, on the magnitude of DD, and also on the gender and age of the subjects (r=−0.891/-0.580; p Conclusion The strength of the study is the analysis of incremental changes in longitudinal contraction in patients with different stage of HTN but not so many the classification of the degree of systolic dysfunction. The importance of our results lies in the fact that these initial changes in systolic contraction could be used as an early sign that should prompt optimization of the treatment of HTN.

  7. Treatment of anemia with darbepoetin alfa in systolic heart failure

    DEFF Research Database (Denmark)

    Swedberg, Karl; Young, James B; Anand, Inder S

    2013-01-01

    Patients with systolic heart failure and anemia have worse symptoms, functional capacity, and outcomes than those without anemia. We evaluated the effects of darbepoetin alfa on clinical outcomes in patients with systolic heart failure and anemia.......Patients with systolic heart failure and anemia have worse symptoms, functional capacity, and outcomes than those without anemia. We evaluated the effects of darbepoetin alfa on clinical outcomes in patients with systolic heart failure and anemia....

  8. Influence of irbesartan combined with low dose urokinase on treatment effect and serologic indexes in elderlyisolated systolic hypertension patients

    Institute of Scientific and Technical Information of China (English)

    Gui-Peng Wang; Xiao-Mei Luo

    2017-01-01

    To study the influence of irbesartan combined with low dose urokinase on treatment effect and serologic indexes in elderly isolated systolic hypertension patients. Methods: One hundred and ten cases of elderly isolated systolic hypertension patients in our hospital during January 2013–January 2016 were randomly divided into observation group with 55 cases and control group with 55 cases. Patients in observation group received irbesartan combined with low dose hydrochlorothiazide treatment and those in control group received amlodipine combined with low dose hydrochlorothiazide treatment, each lasted for 4 weeks. After 4 weeks treatment, non-invasive blood pressure and blood pressure variability indexes were measured, serum endothelial function, inflammatory factors and oxidative stress indexes were measured. Results: After 4 weeks treatment, patients systolic blood pressure (SBP), 24 h mean systolic blood pressure (24 h SBP), 24 h systolic blood pressure standard deviation (24 h SSD) were significantly lower in observation group than in control group (P<0.05); serum endothelial function index EF-1 was lower in observation group than in control group, while NO and endothelial nitric oxide synthase (eNOS) were higher in observation group than in control group (P<0.05); serum high sensitivity C-reactive protein (hs-CRP), interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α (TNF-α) contents were lower in observation group than in control group (P<0.05); serum oxidation index such as malondialdehyde (MDA) was lower in observation group than in control group, while antioxidant indexes such as total anti-oxidative capacity (TAC), superoxide dismutase (SOD), GSH were higher in observation group than in control group (P<0.05). Conclusions: Irbesartan combined with low dose hydrochlorothiazide can effectively reduce systolic hypertension and blood pressure variability in elderly isolated systolic hypertension patients, while optimizing the systemic inflammation and

  9. Changes in electrocardiographic left ventricular hypertrophy and risk of major cardiovascular events in isolated systolic hypertension: the LIFE study

    DEFF Research Database (Denmark)

    Larstorp, A C K; Okin, P M; Devereux, R B;

    2011-01-01

    The predictive value of changes in the severity of electrocardiographic left ventricular hypertrophy (ECG-LVH) during antihypertensive therapy remains unclear in isolated systolic hypertension (ISH). In a Losartan Intervention For Endpoint reduction in hypertension substudy, we included 1320...... patients aged 54–83 years with systolic blood pressure (BP) of 160–200¿mm¿Hg, diastolic BP losartan- or atenolol-based treatment with a mean follow-up of 4.8 years. The composite end point...

  10. Vascular calcification is not associated with increased ambulatory central aortic systolic pressure in prevalent dialysis patients

    Science.gov (United States)

    Freercks, Robert J; Swanepoel, Charles R; Turest-Swartz, Kristy L; Rayner, Brian L; Carrara, Henri RO; Moosa, Sulaiman EI; Lachman, Anthony S

    2014-01-01

    Summary Introduction Central aortic systolic pressure (CASP) strongly predicts cardiovascular outcomes. We undertook to measure ambulatory CASP in 74 prevalent dialysis patients using the BPro (HealthStats, Singapore) device. We also determined whether coronary or abdominal aortic calcification was associated with changes in CASP and whether interdialytic CASP predicted ambulatory measurement. Methods All patients underwent computed tomography for coronary calcium score, lateral abdominal radiography for aortic calcium score, echocardiography for left ventricular mass index and ambulatory blood pressure measurement using BPro calibrated to brachial blood pressure. HealthStats was able to convert standard BPro SOFT® data into ambulatory CASP. Results Ambulatory CASP was not different in those without and with coronary (137.6 vs 141.8 mmHg, respectively, p = 0.6) or aortic (136.6 vs 145.6 mmHg, respectively, p = 0.2) calcification. Furthermore, when expressed as a percentage of brachial systolic blood pressure to control for peripheral blood pressure, any difference in CASP was abolished: CASP: brachial systolic blood pressure ratio = 0.9 across all categories regardless of the presence of coronary or aortic calcification (p = 0.2 and 0.4, respectively). Supporting this finding, left ventricular mass index was also not different in those with or without vascular calcification (p = 0.7 and 0.8 for coronary and aortic calcification). Inter-dialytic office blood pressure and CASP correlated excellently with ambulatory measurements (r = 0.9 for both). Conclusion Vascular calcification was not associated with changes in ambulatory central aortic systolic pressure in this cohort of prevalent dialysis patients. Inter-dialytic blood pressure and CASP correlated very well with ambulatory measurement. PMID:24626513

  11. Relationship between Peripheral Blood T Lymphocyte Subsets and Pulse Pressure in Elderly Patients with Isolated Systolic Hypertension%老年单纯收缩期高血压患者外周血T淋巴细胞亚群和脉压的关系

    Institute of Scientific and Technical Information of China (English)

    尹绢; 寇光; 邱元芝; 陈发秀; 彭乐; 魏群; 胡坚

    2014-01-01

    Objective To investigate the relationship between peripheral blood T lymphocyte subsets and pulse pressure(PP)in elderly patients with isolated systolic hypertension(ISH). Methods Seventy elderly ISH patients(ISH group)and 32 health elderly subjects(control group) were enrolled in this study.In addition,ISH patients were divided into PP0.05).The percentage of CD8+ T cells was positively correlated with PP (r2=0.508,P<0.05).However,the percentages of CD3 and CD4+ T cells were negatively corre-lated with PP(r2=-0.443,P<0.05).Conclusion The increase in PP is associated with immune dysfunction in elderly ISH patients.The increased PP and impaired immune function are impor-tant influence factors in the process of atherosclerosis in elderly patients with ISH.%目的:探讨老年单纯收缩期高血压患者(isolated systolic hypertension,ISH)外周血T淋巴细胞亚群和脉压(pulse pressure,PP)的关系。方法选取70例老年 ISH患者(ISH组)及32例健康老年人(对照组)为研究对象,其中 ISH组按PP水平分为PP<60 mmHg(1 mmHg=0.133 kPa)组(n=33)和PP≥60 mmHg组(n=37)。比较对照组与 ISH组、PP<60 mmHg组和PP≥60 mmHg组患者的 CD3、CD4+、CD8+T细胞百分率和 CD4+/CD8+比值;分析 ISH组PP≥60 mmHg 组 T 淋巴细胞亚群与 PP 水平的关系。结果与对照组比较,ISH 组 CD3、CD4+、CD8+百分率降低、CD4+/CD8+比值增高(P<0.05或P<0.01)。与 PP<60 mmHg组比较,PP≥60 mm-Hg组CD8+T细胞百分率降低、CD4+/CD8+比值增高(均P<0.05);2组 CD3、CD4+百分率差异无统计学意义(P>0.05)。CD8+细胞水平与 PP 水平呈正相关(r2=0.508,P<0.05),CD4+/CD8+比值与 PP 水平呈负相关(r2=-0.443,P<0.05)。结论老年 ISH患者PP增大与免疫功能受损有关,PP及免疫功能紊乱是老年 ISH 患者动脉粥样硬化过程中的重要影响因子。

  12. Modeling of patient's blood pressure variation during ambulance transportation

    Science.gov (United States)

    Sakatani, Kenji; Ono, Takahiko; Kobayasi, Yasuhide; Hikita, Shinichi; Saito, Mitsuyuki

    2007-12-01

    In an emergency transportation by ambulance, a patient is transported in a supine position. In this position, a patient's blood pressure (BP) variation depending on an inertial force which occurs when an ambulance accelerates or decelerates. This BP variation causes a critical damage for a patent with brain disorder. In order to keep a patient stable during transportation, it is required to maintain small BP variation. To analyze the BP variation during transportation, a model of the BP variation has so far been made. But, it can estimate the BP variation only in braking. The purpose of this paper is to make a dynamical model of the BP variation which can simulate it in both braking and accelerating. First, to obtain the data to construct the model, we used a tilting bed to measure a head-to-foot acceleration and BP of fingertip. Based on this data, we build a mathematical model whose input is the head-to-foot acceleration and output is the Mean BP variation. It is a switched model which switches two models depending on the jerk. We add baroreceptor reflex to the model as a offset value.

  13. Low-complexity systolic architecture for inversion

    Institute of Scientific and Technical Information of China (English)

    Yuan Danshou; Rong Mengtian

    2006-01-01

    A modified extended binary Euclid's algorithm which is more regularly iterative for computing an inversion in GF(2m) is presented. Based on above modified algorithm, a serial-in serial-out architecture is proposed. It has area complexity of O(m), latency of 5m-2, and throughput of 1/m. Compared with other serial systolic architectures, the proposed one has the smallest area complexity, shorter latency. It is highly regular, modular, and thus well suited for high-speed VLSI design.

  14. A neurovascular blood-brain barrier in vitro model.

    Science.gov (United States)

    Zehendner, Christoph M; White, Robin; Hedrich, Jana; Luhmann, Heiko J

    2014-01-01

    The cerebral microvasculature possesses certain cellular features that constitute the blood-brain barrier (BBB) (Abbott et al., Neurobiol Dis 37:13-25, 2010). This dynamic barrier separates the brain parenchyma from peripheral blood flow and is of tremendous clinical importance: for example, BBB breakdown as in stroke is associated with the development of brain edema (Rosenberg and Yang, Neurosurg Focus 22:E4, 2007), inflammation (Kuhlmann et al., Neurosci Lett 449:168-172, 2009; Coisne and Engelhardt, Antioxid Redox Signal 15:1285-1303, 2011), and increased mortality. In vivo, the BBB consists of brain endothelial cells (BEC) that are embedded within a precisely regulated environment containing astrocytes, pericytes, smooth muscle cells, and glial cells. These cells experience modulation by various pathways of intercellular communication and by pathophysiological processes, e.g., through neurovascular coupling (Attwell et al., Nature 468:232-243, 2010), cortical spreading depression (Gursoy-Ozdemir et al., J Clin Invest 113:1447-1455, 2004), or formation of oxidative stress (Yemisci et al., Nat Med 15:1031-1037, 2009). Hence, this interdependent assembly of cells is referred to as the neurovascular unit (NVU) (Zlokovic, Nat Med 16:1370-1371, 2010; Zlokovic, Neuron 57:178-201, 2008). Experimental approaches to investigate the BBB in vitro are highly desirable to study the cerebral endothelium in health and disease. However, due to the complex interactions taking place within the NVU in vivo, it is difficult to mimic this interplay in vitro.Here, we describe a murine blood-brain barrier coculture model consisting of cortical organotypic slice cultures and brain endothelial cells that includes most of the cellular components of the NVU including neurons, astrocytes, and brain endothelial cells. This model allows the experimental analysis of several crucial BBB parameters such as transendothelial electrical resistance or tight junction protein localization by

  15. Mesoscopic Modeling of Blood Clotting: Coagulation Cascade and Platelets Adhesion

    Science.gov (United States)

    Yazdani, Alireza; Li, Zhen; Karniadakis, George

    2015-11-01

    The process of clot formation and growth at a site on a blood vessel wall involve a number of multi-scale simultaneous processes including: multiple chemical reactions in the coagulation cascade, species transport and flow. To model these processes we have incorporated advection-diffusion-reaction (ADR) of multiple species into an extended version of Dissipative Particle Dynamics (DPD) method which is considered as a coarse-grained Molecular Dynamics method. At the continuum level this is equivalent to the Navier-Stokes equation plus one advection-diffusion equation for each specie. The chemistry of clot formation is now understood to be determined by mechanisms involving reactions among many species in dilute solution, where reaction rate constants and species diffusion coefficients in plasma are known. The role of blood particulates, i.e. red cells and platelets, in the clotting process is studied by including them separately and together in the simulations. An agonist-induced platelet activation mechanism is presented, while platelets adhesive dynamics based on a stochastic bond formation/dissociation process is included in the model.

  16. A multiscale model for red blood cell mechanics.

    Science.gov (United States)

    Hartmann, Dirk

    2010-02-01

    The objective of this article is the derivation of a continuum model for mechanics of red blood cells via multiscale analysis. On the microscopic level, we consider realistic discrete models in terms of energy functionals defined on networks/lattices. Using concepts of Gamma-convergence, convergence results as well as explicit homogenisation formulae are derived. Based on a characterisation via energy functionals, appropriate macroscopic stress-strain relationships (constitutive equations) can be determined. Further, mechanical moduli of the derived macroscopic continuum model are directly related to microscopic moduli. As a test case we consider optical tweezers experiments, one of the most common experiments to study mechanical properties of cells. Our simulations of the derived continuum model are based on finite element methods and account explicitly for membrane mechanics and its coupling with bulk mechanics. Since the discretisation of the continuum model can be chosen freely, rather than it is given by the topology of the microscopic cytoskeletal network, the approach allows a significant reduction of computational efforts. Our approach is highly flexible and can be generalised to many other cell models, also including biochemical control.

  17. The reliability of toe systolic pressure and the toe brachial index in patients with diabetes

    Directory of Open Access Journals (Sweden)

    Perrin Byron M

    2010-12-01

    Full Text Available Abstract Background The Ankle Brachial Index is a useful clinical test for establishing blood supply to the foot. However, there are limitations to this method when conducted on people with diabetes. As an alternative to the Ankle Brachial Index, measuring Toe Systolic Pressures and the Toe Brachial Index have been recommended to assess the arterial blood supply to the foot. This study aimed to determine the intra and inter-rater reliability of the measurement of Toe Systolic Pressure and the Toe Brachial Index in patients with diabetes using a manual measurement system. Methods This was a repeated measures, reliability study. Three raters measured Toe Systolic Pressure and the Toe Brachial Index in thirty participants with diabetes. Measurement sessions occurred on two occasions, one week apart, using a manual photoplethysmography unit (Hadeco Smartdop 45 and a standardised measurement protocol. Results The mean intra-class correlation for intra-rater reliability for toe systolic pressures was 0.87 (95% LOA: -25.97 to 26.06 mmHg and the mean intra-class correlation for Toe Brachial Indices was 0.75 (95% LOA: -0.22 to 0.28. The intra-class correlation for inter-rater reliability was 0.88 for toe systolic pressures (95% LOA: -22.91 to 29.17.mmHg and 0.77 for Toe Brachial Indices (95% LOA: -0.21 to 0.22. Conclusion Despite the reasonable intra-class correlation results, the range of error (95% LOA was broad. This raises questions regarding the reliability of using a manual sphygmomanometer and PPG for the Toe Systolic Pressure and Toe Brachial Indice.

  18. Performance of enlarged blood pump models with five different impellers.

    Science.gov (United States)

    Chua, L P; Yu, S C; Leo, H L

    2000-01-01

    In earlier studies, a 5:1 enlarged pump model of the Kyoto-NTN Magnetically Suspended Centrifugal Blood Pump had been constructed and the flow characteristics investigated. Although the results obtained were satisfactory, the medium used was air. A 5:1 enlarged pump model using water as the medium thus was designed and constructed. Five different impeller blade profile designs were used in the present study. By varying (1) the blade profile design: forward, radial, and backward, (2) the number of blades used, and (3) the rotating speed, the flow characteristics of the pump were investigated. It was found that the impeller with the higher number of blades, used in the forward and straight blade profiles, have the best performance.

  19. Blood components and OCT reflectivity evaluated in animal model.

    Science.gov (United States)

    Sonoda, Shozo; Sakamoto, Taiji; Shirasawa, Makoto; Yamashita, Takehiro; Uchino, Eisuke; Terasaki, Hiroto

    2014-12-01

    To see the relationship between blood components and optical coherence tomography (OCT) reflectivity using an animal model in which the aqueous humor was substituted by different experimental solutions without changing the integrity of the retina. The aqueous humor of an enucleated swine eye was replaced with plasma obtained from healthy volunteers. The OCT reflectivity of the anterior chamber filled with each plasma was calculated from individual OCT images, and was expressed by an arbitrary unit (AU). The concentration of blood components such as cholesterol, hemoglobin (Hb) and bilirubin of each individual was measured, and the correlation between each of them and the OCT reflectivity of aqueous humor in an enucleated swine eye was analyzed. Using the same model, the effects of the single plasma component on OCT reflectivity were examined. Blood samples were obtained from 24 individuals. OCT reflectivity was 30.68 ± 14.8 AU (average ± SD), ranging from 11.11 to 60.31 AU. OCT reflectivity correlated significantly with the concentration of triglycerides (R = 0.634, p = 0.001) and total cholesterol (R = 0.488, p = 0.015) using Spearman's rank correlation coefficient. While a partial correlation analysis showed that it correlated significantly with triglyceride (R = 0.60, p = 0.003), but not total cholesterol. OCT reflectivity was highest in a balanced salt solution (BSS) with Hb (average 42.05 AU), followed by fibrinogen (8.08 AU), bilirubin (6.12 AU) and γ-globulin (2.85 AU). Albumin did not increase the reflectivity of the BSS with a normal concentration (1.11 AU) compared to the control BSS alone (0.73 AU). OCT reflectivity was most strongly affected by the presence of triglycerides among the blood components. Some molecules such as Hb and fibrinogen significantly increase the OCT reflectivity. This information should be helpful for interpreting the OCT findings correctly.

  20. PIV validation of blood-heart valve leaflet interaction modelling.

    Science.gov (United States)

    Kaminsky, R; Dumont, K; Weber, H; Schroll, M; Verdonck, P

    2007-07-01

    The aim of this study was to validate the 2D computational fluid dynamics (CFD) results of a moving heart valve based on a fluid-structure interaction (FSI) algorithm with experimental measurements. Firstly, a pulsatile laminar flow through a monoleaflet valve model with a stiff leaflet was visualized by means of Particle Image Velocimetry (PIV). The inflow data sets were applied to a CFD simulation including blood-leaflet interaction. The measurement section with a fixed leaflet was enclosed into a standard mock loop in series with a Harvard Apparatus Pulsatile Blood Pump, a compliance chamber and a reservoir. Standard 2D PIV measurements were made at a frequency of 60 bpm. Average velocity magnitude results of 36 phase-locked measurements were evaluated at every 10 degrees of the pump cycle. For the CFD flow simulation, a commercially available package from Fluent Inc. was used in combination with inhouse developed FSI code based on the Arbitrary Lagrangian-Eulerian (ALE) method. Then the CFD code was applied to the leaflet to quantify the shear stress on it. Generally, the CFD results are in agreement with the PIV evaluated data in major flow regions, thereby validating the FSI simulation of a monoleaflet valve with a flexible leaflet. The applicability of the new CFD code for quantifying the shear stress on a flexible leaflet is thus demonstrated.

  1. Theoretical model of blood flow measurement by diffuse correlation spectroscopy

    Science.gov (United States)

    Sakadžić, Sava; Boas, David A.; Carp, Stefan

    2017-02-01

    Diffuse correlation spectroscopy (DCS) is a noninvasive method to quantify tissue perfusion from measurements of the intensity temporal autocorrelation function of diffusely scattered light. However, DCS autocorrelation function measurements in tissue better match theoretical predictions based on the diffusive motion of the scatterers than those based on a model where the advective nature of blood flow dominates the stochastic properties of the scattered light. We have recently shown using Monte Carlo (MC) simulations and assuming a simplistic vascular geometry and laminar flow profile that the diffusive nature of the DCS autocorrelation function decay is likely a result of the shear-induced diffusion of the red blood cells. Here, we provide theoretical derivations supporting and generalizing the previous MC results. Based on the theory of diffusing-wave spectroscopy, we derive an expression for the autocorrelation function along the photon path through a vessel that takes into account both diffusive and advective scatterer motion, and we provide the solution for the DCS autocorrelation function in a semi-infinite geometry. We also derive the correlation diffusion and correlation transfer equation, which can be applied for an arbitrary sample geometry. Further, we propose a method to take into account realistic vascular morphology and flow profile.

  2. Cost-effectiveness of Intensive Blood Pressure Management

    DEFF Research Database (Denmark)

    Richman, Ilana B; Fairley, Michael; Jørgensen, Mads Emil

    2016-01-01

    . Objective: To evaluate the incremental cost-effectiveness of intensive blood pressure management compared with standard management. Design, Setting, and Participants: This cost-effectiveness analysis conducted from September 2015 to August 2016 used a Markov cohort model to estimate cost-effectiveness...... of intensive blood pressure management among 68-year-old high-risk adults with hypertension but not diabetes. We used the Systolic Blood Pressure Intervention Trial (SPRINT) to estimate treatment effects and adverse event rates. We used Centers for Disease Control and Prevention Life Tables to project age....... Interventions: Treatment of hypertension to a systolic blood pressure goal of 120 mm Hg (intensive management) or 140 mm Hg (standard management). Main Outcomes and Measures: Lifetime costs and quality-adjusted life-years (QALYs), discounted at 3% annually. Results: Standard management yielded 9.6 QALYs...

  3. Systolic and diastolic dysfunction of the right heart ventricle in patients with chronic obstructive pulmonary disease in extremely cold climate.

    Science.gov (United States)

    Sivtseva, Anna Innokentievna; Strutynsky, Andrew Vladislavovich; Krivoshapkin, Vadim Grigorievich; Sivtseva, Elena Nikolaevna; Ivanova, Marianna Adolfovna; Timofeev, Leonid Fedorovich

    2014-11-30

    The paper describes echocardiographic values of systolic and diastolic dysfunction the right heart ventricle in 229 patients with chronic obstructive pulmonary disease. In our patients the values AvPAP (?25 mmHg while resting), FDDrv and FSDrv (>26 and 20 mm respectively), the thickness of front wall the RV (>5 mm), the dimension of AD (>35 mm), as well as the reduction the vestibular-distal shortening of RV (<23%), maximum blood velocity and the blood evacuation time from reflect indirectly the progressive reduction the contractive capacity RV myocardium and the occurrence of systolic dysfunction. In patients with severe de-compensation a restrictive type diastolic function is more characteristic - acceleration of early diastolic filling and blood velocity decrease during the auricular systole.

  4. Measurements of enlarged blood pump models using Laser Doppler Anemometer.

    Science.gov (United States)

    Chua, L P; Yu, S C; Leo, H L

    2000-01-01

    In an earlier study (Chua et al., 1998, 1999a), a 5:1 enlarged model of the Kyoto-NTN Magnetically Suspended Centrifugal Blood Pump (Akamatsu et al., 1995) with five different impeller blade profiles was designed and constructed. Their respective flow characteristics with respect to (1) the three different blade profile designs: forward, radial, and backward, (2) the number of blades used, and (3) the rotating speed were investigated. Among the five impeller designs, the results obtained suggested that impellers A and C designs should be adopted if higher head is required. Impellers A and C therefore were selected for the flow in between their blades to be measured using Laser Doppler Anemometer (LDA), so as to have a better understanding of the flow physics with respect to the design parameters.

  5. 入院收缩压对急性ST段抬高心肌梗死预后的研究%Research of systolic blood pressure at admission on in-hospital outcomes in patients with ST elevated acute myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    金帅; 桑真真; 贾冬; 许云; 张鹏思; 赵敏

    2014-01-01

    Objective To investigate the impact of systolic blood pressure (SBP) at admission on in-hospital outcomes in patients with ST elevated acute myocardial infarction (STEMI).Methods Data of 336 STEMI patients admitted from September 2008 to May 2011 were retrospectively analyzed.Total of 336 STEMI patients were classified into 4 groups as per the level of SBP at admission:group A (< 101 mmHg,n =59) ; group B (101-120 mmHg,n =109) ; group C (121-140 mmHg,n =98) and group D (> 140 mmHg,n =69).And clinical features,coronary angiography (CAG) findings,the strategy of treatment,complications and hospital mortality were compared among 4 groups with SPSS version 18.0 software.Results The mortality rates of the four groups were 18.64%,1.83%,4.08%,1.45%,respectively.The patients with SBP < 106 mmHg were in greater risk of in-hospital mortality,Killip class ≥ 3 at admission,shock and refractory arrhythmias,and more patients in this group needed pacemaker and intraaortic balloon pump (IABP) treatment than patients in other 3 groups.While there was no significant difference in mortality rate between other three groups.Multivariate logistic regression analysis demonstrated SBP < 101 mmHg (OR =6.368,P =0.002) and peak value of troponin Ⅰ (OR =3.781,P =0.008) were independent risk factors of in-hospital death in STEMI patients.Conclusions The STEMI patients with SBP < 101 mmHg at admission had higher mortality rate and low SBP at admission had great prognostic value in short-term outcomes of STEMI.%目的 研究入院时收缩压(systolic blood pressure-SBP)水平对急性ST段抬高心肌梗死(STEMI)在院期间预后的影响.方法 回顾性分析中国医科大学附属盛京医院2008年9月至2011年6月收治入院的335例STEMI患者,根据入院时SBP水平将335例STEMI患者分为4组,分别是:<101 mmHg(1 mmHg=0.133 kPa) (n=59),101~120 mmHg (n=109),121 ~140mmHg(n=98),>140 mmHg (n =69).比较各组的基本临床资料

  6. Dietary phosphorus and blood pressure: international study of macro- and micro-nutrients and blood pressure.

    Science.gov (United States)

    Elliott, Paul; Kesteloot, Hugo; Appel, Lawrence J; Dyer, Alan R; Ueshima, Hirotsugu; Chan, Queenie; Brown, Ian J; Zhao, Liancheng; Stamler, Jeremiah

    2008-03-01

    Raised blood pressure is a leading cause of morbidity and mortality worldwide; improved nutritional approaches to population-wide prevention are required. Few data are available on dietary phosphorus and blood pressure and none are available on possible combined effects of phosphorus, magnesium, and calcium on blood pressure. The International Study of Macro- and Micro-Nutrients and Blood Pressure is a cross-sectional epidemiologic study of 4680 men and women ages 40 to 59 from 17 population samples in Japan, China, United Kingdom, and United States. Blood pressure was measured 8 times at 4 visits. Dietary intakes were obtained from four 24-hour recalls plus data on supplement use. Dietary phosphorus was inversely associated with blood pressure in a series of predefined multiple regression models, with the successive addition of potential confounders, both nondietary and dietary. Estimated blood pressure differences per 232 mg/1000 kcal (2 SD) of higher dietary phosphorus were -1.1 to -2.3 mm Hg systolic/-0.6 to -1.5 mm Hg diastolic (n=4680) and -1.6 to -3.5 mm Hg systolic/-0.8 to -1.8 mm Hg diastolic for 2238 "nonintervened" individuals, ie, those without special diet/nutritional supplements or diagnosis/treatment for cardiovascular disease or diabetes. Dietary calcium and magnesium, correlated with phosphorus (partial r=0.71 and r=0.68), were inversely associated with blood pressure. Blood pressures were lower by 1.9 to 4.2 mm Hg systolic/1.2 to 2.4 mm Hg diastolic for people with intakes above versus below country-specific medians for all 3 of the minerals. These results indicate the potential for increased phosphorus/mineral intake to lower blood pressure as part of the recommendations for healthier eating patterns for the prevention and control of prehypertension and hypertension.

  7. Modelling of the Blood Coagulation Cascade in an In Vitro Flow System

    DEFF Research Database (Denmark)

    Andersen, Nina Marianne; Sørensen, Mads Peter; Efendiev, Messoud A.;

    2010-01-01

    We derive a mathematical model of a part of the blood coagulation cascade set up in a perfusion experiment. Our purpose is to simulate the influence of blood flow and diffusion on the blood coagulation pathway. The resulting model consists of a system of partial differential equations taking into...... and flow equations, which guarantee non negative concentrations at all times. The criteria is applied to the model of the blood coagulation cascade.......We derive a mathematical model of a part of the blood coagulation cascade set up in a perfusion experiment. Our purpose is to simulate the influence of blood flow and diffusion on the blood coagulation pathway. The resulting model consists of a system of partial differential equations taking...

  8. Assessment of left ventricular systolic and diastolic function in juvenile rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Bharti Bishwa Bhushan

    2004-10-01

    Full Text Available Background and Aims: Recognizing the paucity of data regarding echocardiographic studies of Left ventricular (LV systolic and diastolic function in patients with juvenile rheumatoid arthritis (JRA, a study was carried out to study these parameters in these subjects. Settings, Design and Methods: Thirty-five patients with JRA and an equal number of age- and sex-matched controls were studied by two-dimensional and Doppler echocardiography. Results: Patients with JRA had higher systolic and diastolic blood pressures, resting heart rates, LV systolic (26.9±4.3 vs. 22.4 ± 4.1 mm, p=0.001 and diastolic size (42.3±4.6 vs. 35.4±3.8 mm, p<0.001 and volumes. Though ejection fraction (EF and fractional shortening (FS were normal, they were lower in those with JRA as compared to controls (EF: 62.9±4.47 vs. 67.5±3.63 %, p<0.001; FS: 36.4±4.5 vs. 38.5 ± 6.87, p=0.2. On Doppler analysis the JRA group had lower peak E velocity, higher peak A velocity, higher A VTI and more prolonged IVRT. Male patients had higher A VTI and IVRT as compared to females. Those with longer duration of disease had larger LV systolic (r=0.517, p=0.01 and diastolic dimension (r=0.40, p=0.05 and lower FS (r=-0.506, p=0.01. Patients with polyarticular JRA had higher E and A VTI as compared to those with systemic or oligoarticular types. Conclusion: Despite an asymptomatic cardiac status, significant systolic and diastolic functional abnormalities exist in patients with JRA. The duration of the disease, mode of presentation, patient's age and gender have a significant impact on the left ventricular systolic and diastolic functions in patients with JRA.

  9. Familial aggregation of seven-year changes in blood pressure in Canada.

    Science.gov (United States)

    Katzmarzyk, P T; Pérusse, L; Rice, T; Rao, D C; Bouchard, C

    2001-12-01

    To determine the familial resemblance for baseline and seven-year changes in blood pressure in the Canadian population. The study participants were 857 people from 348 families in the 1988 Campbell's Survey, which was a seven-year follow-up of the Canada Fitness Survey. Systolic and diastolic blood pressures were measured at baseline and at follow-up, and were adjusted for age and body mass index by using regression analysis. Familial correlation models were fit to the data by using path analysis, and maximal heritabilities were calculated from the most parsimonious models. There was significant familial resemblance for baseline blood pressure and changes in blood pressure. In general, all classes of familial correlations (spousal, parent-offspring and sibling) were significant and were of comparable magnitude. The maximal heritabilities, which are influenced to an unknown degree by genes and shared environmental factors, were 50% and 70% for diastolic and systolic blood pressures, respectively, and 66% and 41% for seven-year changes in diastolic and systolic blood pressures, respectively. There is significant familial aggregation for blood pressure and for natural changes in blood pressure in the Canadian population. Genes may be important in explaining the familial resemblance for blood pressure; however, the presence of significant spousal correlations suggests that shared lifestyle and family environments are also important factors in the familial aggregation.

  10. Echocardiographic quantification of systolic function during atrial fibrillation

    DEFF Research Database (Denmark)

    Olsen, Flemming Javier; Jørgensen, Peter Godsk; Dons, Maria;

    2016-01-01

    It is often difficult to provide an exact echocardiographic measure of left ventricular systolic function in patients with atrial fibrillation, partly because of the varying cycle length affecting pre and afterload and partly because of the increased heart rate often accompanying this arrhythmia....... We sought to elucidate two points: whether it would be possible to correct for the cyclic variance in systolic output, and if global longitudinal strain is preferable to the left ventricular ejection fraction at evaluating systolic function during atrial fibrillation....

  11. Coronary artery ectasia and systolic flow cessation in a patient with hypertrophic cardiomyopathy: a case report.

    Science.gov (United States)

    Zografos, Theodoros; Kokladi, Maria; Katritsis, Demosthenes

    2010-12-01

    Coronary artery ectasia (CAE) is characterized by diffuse or localized inappropriate dilation of coronary arteries and is often associated with slow coronary blood flow. Although CAE has been described to coexist with several clinical entities there are only three reports of CAE in the presence of hypertrophic cardiomyopathy (HCM). We report a case of CAE and slow coronary flow with systolic flow cessation in a 61-year old male with coronary artery disease and HCM.

  12. Evaluation of Prehospital Blood Products to Attenuate Acute Coagulopathy of Trauma in a Model of Severe Injury and Shock in Anesthetized Pigs.

    Science.gov (United States)

    Watts, Sarah; Nordmann, Giles; Brohi, Karim; Midwinter, Mark; Woolley, Tom; Gwyther, Robert; Wilson, Callie; Poon, Henrietta; Kirkman, Emrys

    2015-08-01

    Acute trauma coagulopathy (ATC) is seen in 30% to 40% of severely injured casualties. Early use of blood products attenuates ATC, but the timing for optimal effect is unknown. Emergent clinical practice has started prehospital deployment of blood products (combined packed red blood cells and fresh frozen plasma [PRBCs:FFP], and alternatively PRBCs alone), but this is associated with significant logistical burden and some clinical risk. It is therefore imperative to establish whether prehospital use of blood products is likely to confer benefit. This study compared the potential impact of prehospital resuscitation with (PRBCs:FFP 1:1 ratio) versus PRBCs alone versus 0.9% saline (standard of care) in a model of severe injury. Twenty-four terminally anesthetised Large White pigs received controlled soft tissue injury and controlled hemorrhage (35% blood volume) followed by a 30-min shock phase. The animals were allocated randomly to one of three treatment groups during a 60-min prehospital evacuation phase: hypotensive resuscitation (target systolic arterial pressure 80 mmHg) using either 0.9% saline (group 1, n = 9), PRBCs:FFP (group 2, n = 9), or PRBCs alone (group 3, n = 6). Following this phase, an in-hospital phase involving resuscitation to a normotensive target (110 mmHg systolic arterial blood pressure) using PRBCs:FFP was performed in all groups. There was no mortality in any group. A coagulopathy developed in group 1 (significant increase in clot initiation and dynamics shown by TEG [thromboelastography] R and K times) that persisted for 60 to 90 min into the in-hospital phase. The coagulopathy was significantly attenuated in groups 2 and 3 (P = 0.025 R time and P = 0.035 K time), which were not significantly different from each other. Finally, the volumes of resuscitation fluid required was significantly greater in group 1 compared with groups 2 and 3 (P = 0.0067) (2.8 ± 0.3 vs. 1.9 ± 0.2 and 1.8 ± 0.3 L, respectively). This difference was principally

  13. CHANGES IN CARDIAC STATUS DUE TO ISOLATED SYSTOLIC HYPERTENSION BY NON - INVASIVE STUDIES

    Directory of Open Access Journals (Sweden)

    Sourangsu

    2014-01-01

    Full Text Available AIM : It was thought previously that morbidity and mortality are directly related to both Systolic and Diastolic blood pressure . However evidences from different studies suggest that systolic hypertension deserves more importance especially due to its profound effect on cardiovascular disease progression. Isolated systolic hypertension (ISH has now increased amongst the elderly population due to inc reased longevity. METHOD : Total 240 patients of 65 – 89 years age group were taken as study group at the out - patient and in - door department of CNMC Kolkata and NBMC , Siliguri. All patients were divided into three groups based on systolic blood pressure : Gr A=SBP - 140 — 159 mmHg , Gr B=SBP - 160 - 179 mmHg & Gr C=SBP>180 mmHg with each group having age and sex matched 100 healthy normotensive control subjects. History , Clinical examination , ECG and Echocardiographic studies were done in the selected patients . Sop histicated tests were not done due to nonavailability. RESULTS : Major Electrocardiogram changes are left atrial enlargement , left ventricular hypertrophy with systolic strain , Inferior wall ischemia , both bundle branch blocks , bifascicular block , left axis deviation. Other minor changes were : antero - septal ischemia , septal wall ischemia , lateral wallischemia , right axis deviation , arrhythmia , and low voltage were also noted. Echocardiography in 2 - D and M - ModeandEcho - Doppler assessment showed incre ased Intraventricular septal thickness (IVST , Left ventricular posterior wall Thickness (LVPWT and Left ventricular mass index were the major changes. Left ventricular functional abnormality like diastolic dysfunction was another significant abnormality. CONCLUSION : Different anatomical & functional changes in ISH are more prevalent in higher SBP group , and strong risk factor for future catastrophic cardiac events. It is an independent risk factor for CVS morbidity and mortality. Early therapeutic interve ntion

  14. Real-Time Blood Donor Management Using Dashboards Based on Data Mining Models

    Directory of Open Access Journals (Sweden)

    Santhanam T

    2011-09-01

    Full Text Available This study uses data mining modeling techniques to examine the blood donor classification and extending this to facilitate the development of realtime blood donor management using dashboards with blood profile and geo-location data. This enables decision makers the ability to manage and plan the blood donation activities based on key metrics. This capability provides the ability to plan effective targeted blood donation campaigns. The scoring algorithm implemented for the dashboard also helps in the optimized deployment of budget resources and budget allocation determination for blood donation campaigns.

  15. ABO/Rh Blood-Typing Model: A Problem-Solving Activity

    Science.gov (United States)

    Wake, Carol

    2005-01-01

    An ARO/Rh Blood-Typing kit useful for students to visualize blood-typing activities and practice problem-solving skills with transfusion reactions is presented. The model also enables students to identify relationships between A, B, and Rh antigens and antibodies in blood and to understand molecular mechanisms involved in transfusion agglutination…

  16. Dynamic Modeling of Renal Blood Flow in Dahl Hypertensive and Normotensive Rats

    DEFF Research Database (Denmark)

    Knudsen, Torben; Elmer, H.; Knudsen, Morten;

    2004-01-01

    A method is proposed in this paper which allows characterisation of renal autoregulatory dynamics and efficiency using quantitative mathematical methods. Based on data from rat experiments, where arterial blood pressure and renal blood flow are measured, a quantitative model for renal blood flow ...

  17. ABO/Rh Blood-Typing Model: A Problem-Solving Activity

    Science.gov (United States)

    Wake, Carol

    2005-01-01

    An ARO/Rh Blood-Typing kit useful for students to visualize blood-typing activities and practice problem-solving skills with transfusion reactions is presented. The model also enables students to identify relationships between A, B, and Rh antigens and antibodies in blood and to understand molecular mechanisms involved in transfusion agglutination…

  18. Associations of blood pressure change in pregnancy with fetal growth and gestational age at delivery: findings from a prospective cohort.

    Science.gov (United States)

    Macdonald-Wallis, Corrie; Tilling, Kate; Fraser, Abigail; Nelson, Scott M; Lawlor, Debbie A

    2014-07-01

    Hypertensive disorders of pregnancy are associated with intrauterine growth restriction and preterm birth. However, the associations of patterns of blood pressure change during pregnancy with these outcomes have not been studied in detail. We studied repeat antenatal blood pressure measurements of 9697 women in the Avon Longitudinal Study of Parents and Children (median [interquartile range], 10 [9-11] measurements per woman). Bivariate linear spline models were used to relate blood pressure changes to perinatal outcomes. Higher systolic, but not diastolic, blood pressure at baseline (8 weeks of gestation) and a greater increase in systolic and diastolic blood pressure between 18 and 36 weeks of gestation were associated with lower offspring birth weight and being smaller for gestational age in confounder-adjusted models. For example, the mean difference (95% confidence interval) in birth weight per 1 mm Hg/wk greater increase in systolic blood pressure between 18 and 30 weeks was -71 g (-134 to -14) and between 30 and 36 weeks was -175 g (-208 to -145). A smaller decrease in systolic and diastolic blood pressure before 18 weeks and a greater increase between 18 and 36 weeks were associated with a shorter gestation (percentage difference in gestational duration per 1 mm Hg/wk greater increase in systolic blood pressure between 18 and 30 weeks was -0.60% [-1.01 to -0.18] and between 30 and 36 weeks was -1.01% [-1.36 to -0.74]). Associations remained strong when restricting to normotensive women. We conclude that greater increases in blood pressure, from the 18-week nadir, are related to reduced fetal growth and shorter gestation even in women whose blood pressure does not cross the threshold for hypertensive disorders of pregnancy. © 2014 American Heart Association, Inc.

  19. Prediction models for hemoglobin deferral in whole blood donors

    NARCIS (Netherlands)

    Baart, A.M.

    2013-01-01

    Each year, a relevant proportion of the invited blood donors is eventually deferred from donation because of low hemoglobin (Hb) levels. Deferrals are meant to protect donors from developing iron deficiency anemia after a blood donation, however, they may increase the risk of donor lapse, even thoug

  20. Modelling Cerebral Blood Flow and Temperature Using a Vascular Porous Model

    Science.gov (United States)

    Blowers, Stephen; Thrippleton, Michael; Marshall, Ian; Harris, Bridget; Andrews, Peter; Valluri, Prashant

    2016-11-01

    Macro-modelling of cerebral blood flow can assist in determining the impact of temperature intervention to reduce permanent tissue damage during instances of brain trauma. Here we present a 3D two phase fluid-porous model for simulating blood flow through the capillary region linked to intersecting 1D arterial and venous vessel trees. This combined vasculature porous (VaPor) model simulates both flow and energy balances, including heat from metabolism, using a vasculature extracted from MRI data which are expanded upon using a tree generation algorithm. Validation of temperature balance has been achieved using rodent brain data. Direct flow validation is not as straight forward due to the method used in determining regional cerebral blood flow (rCBF). In-vivo measurements are achieved using a tracer, which disagree with direct measurements of simulated flow. However, by modelling a virtual tracer, rCBF values are obtained that agree with those found in literature. Temperature profiles generated with the VaPor model show a reduction in core brain temperature after cooling the scalp not seen previously in other models.

  1. Assessment of right ventricular systolic function by tissue Doppler echocardiography

    DEFF Research Database (Denmark)

    Kjærgaard, Jesper

    2012-01-01

    myocardial velocities, but no changes in SR, strain or isovolumic acceleration could be observed [II and III]. Tissue Doppler echocardiography of the RV free wall in non-massive pulmonary embolism quantifies degree of RV dysfunction, and supports the existence of the McConnell sign of mid-ventricular RV...... structure including significant dilatation, but is well tolerated with only mild reduction in measures of global RV systolic function as estimated by 2D echocardiography in an experimental animal model. Regional RV myocardial function is also only mildly reduced. Also no differences in global or regional RV......This thesis summarizes a series of studies performed in order to assess the clinical usefulness of a novel echocardiographic technology that allows non-invasive assessment of regional right ventricular myocardial velocities and deformation: tissue Doppler echocardiography. While the technology...

  2. An artificial blood vessel implanted three-dimensional microsystem for modeling transvascular migration of tumor cells.

    Science.gov (United States)

    Wang, Xue-Ying; Pei, Ying; Xie, Min; Jin, Zi-He; Xiao, Ya-Shi; Wang, Yang; Zhang, Li-Na; Li, Yan; Huang, Wei-Hua

    2015-02-21

    Reproducing a tumor microenvironment consisting of blood vessels and tumor cells for modeling tumor invasion in vitro is particularly challenging. Here, we report an artificial blood vessel implanted 3D microfluidic system for reproducing transvascular migration of tumor cells. The transparent, porous and elastic artificial blood vessels are obtained by constructing polysaccharide cellulose-based microtubes using a chitosan sacrificial template, and possess excellent cytocompatibility, permeability, and mechanical characteristics. The artificial blood vessels are then fully implanted into the collagen matrix to reconstruct the 3D microsystem for modeling transvascular migration of tumor cells. Well-defined simulated vascular lumens were obtained by proliferation of the human umbilical vein endothelial cells (HUVECs) lining the artificial blood vessels, which enables us to reproduce structures and functions of blood vessels and replicate various hemodynamic parameters. Based on this model, the adhesion and transvascular migration of tumor cells across the artificial blood vessel have been well reproduced.

  3. [Experimental modeling of the blood vessels magnetic embolization].

    Science.gov (United States)

    Iacob, Gh; Ciochină, Al D; Bredeţean, O

    2005-01-01

    The embolization of blood vessels is used on a large scale: the method is applied in different diseases, in the ablation of organs, but especially in tumor necrosis. The embolization can be also magnetic, if the embolus is obtained through the deposit in the vessel of magnetic nano or microparticles in the presence of an external magnetic field. The objective of our study was the modeling of the magnetic embolization using amorphous magnetic microspheres that have strong magnetic properties and are biocompatible. Experimental tests were made in order to observe the building of the magnetic embolus inside a thin spiral tube and to determine the influence of some parameters on the efficiency of occlusions: the dimensions of magnetic microspheres (1-300 mm), the debit of the liquid (4.66 - 16.5 ml/min), the viscosity of the carrier liquid (1.007 - 7.34 cSt), the direction and the intensity of the external magnetic field (340 - 600 Gs), the shape of the tube and the linear length of the deposit (5 - 50 mm). Under pre-established experimental conditions the efficiencies of occlusions were between 67% and 100%.

  4. Hemodynamic and Mechanical Properties of the Proximal Aorta in Young and Middle-Aged Adults With Isolated Systolic Hypertension: The Dallas Heart Study.

    Science.gov (United States)

    Yano, Yuichiro; Neeland, Ian J; Ayers, Colby; Peshock, Ronald; Berry, Jarett D; Lloyd-Jones, Donald M; Greenland, Philip; Mitchell, Gary F; Vongpatanasin, Wanpen

    2017-07-01

    The aim of this study was to assess characteristic impedance (Zc) of the proximal aorta in young and middle-aged individuals with isolated systolic hypertension (ISH). Zc is an index of aortic stiffness relative to aortic size. In the Dallas Heart Study, 2001 untreated participants 18 to 64 years of age (mean age: 42.3 years; 44% black race) were divided into the following groups based on office blood pressure (BP) measurements: (1) optimal BP (systolic BP [SBP] hypertension (SBP hypertension (SBP ≥140 mm Hg and DBP ≥90 mm Hg; n=178). Zc, aortic arch pulse wave velocity, and minimum ascending aortic size were quantified using cardiovascular magnetic resonance. In multivariable-adjusted linear models, Zc was highest in the ISH group compared with the optimal BP, isolated diastolic hypertension, or systolic-diastolic hypertension groups (103.2±4.0 versus 68.3±2.1, 75.4±6.0, and 88.9±4.8 dyne*seconds/cm(5), respectively; all Phypertension, or systolic-diastolic hypertension groups (6.3±0.3 versus 4.3±0.1, 4.4±0.4 and 5.5±0.3 m/s, respectively; all P0.2). Results were similar in a subgroup of 1551 participants 18 to 49 years of age. In a multiracial population-based sample, we found evidence of a mismatch between proximal aortic stiffness and diameter in young and middle-aged adults with ISH. © 2017 American Heart Association, Inc.

  5. Computational Modeling of Blood Flow and Valve Dynamics in Hearts with Hypertrophic Cardiomyopathy

    Science.gov (United States)

    Zheng, Xudong; Mittal, Rajat; Abraham, Theodore; Pinheiro, Aurelio

    2010-11-01

    Hypertrophic Cardiomyopathy (HCM) is a cardiovascular disease manifested by the thickening of the ventricular wall and often leads to a partial obstruction to the blood flow out of the left ventricle. HCM is recognized as one of the most common causes of sudden cardiac death in athletes. In a heart with HCM, the hypertrophy usually narrows the blood flow pathway to the aorta and produces a low pressure zone between the mitral valve and the hypertrophy during systole. This low pressure can suck the mitral valve leaflet back and completely block the blood flow into the aorta. In the current study, a sharp interface immersed boundary method flow solver is employed to study the hemodynamics and valve dynamics inside a heart with HCM. The three-dimensional motion and configuration of the left ventricle including mitral valve leaflets and aortic valves are reconstructed based on echo-cardio data sets. The mechanisms of aortic obstruction associated with HCM are investigated. The long term objective of this study is to develop a computational tool to aid in the assessment and surgical management of HCM.

  6. Effects of green tea supplementation on inflammation markers, antioxidant status and blood pressure in NaCl-induced hypertensive rat model

    Science.gov (United States)

    Szulińska, Monika; Stępień, Marta; Kręgielska-Narożna, Matylda; Suliburska, Joanna; Skrypnik, Damian; Bąk-Sosnowska, Monika; Kujawska-Łuczak, Magdalena; Grzymisławska, Małgorzata; Bogdański, Paweł

    2017-01-01

    ABSTRACT Background: Recent studies indicate the important role of chronic inflammation and oxidative stress in the pathogenesis of hypertension. Green tea, due to the high content of catechins, shows high antioxidant activity. Objective: To determine the effect of supplementation with green tea extract on the blood pressure, on the concentration of selected parameters of inflammation and antioxidant status in the model of high-sodium-diet induced hypertension. Design: The study lasted 42 days. The experimental population consisted of 30 rats. The rats were divided into three groups. The rats in the control group were fed a standard diet with 35 g of NaCl per kg of diet, in the second group hypertensive rats were fed a standard diet with NaCl (35 g/kg diet) and with an extract of green tea (2 g/kg diet). The third group consisted of hypertensive rats fed a standard diet with NaCl (35 g/kg diet), and 4 g of green tea extract/kg diet. Results: Supplementation with green tea had no effect on body mass of rats on a high-sodium diet. At the end of the experiment systolic blood pressures in SH2 and SH4 groups were significantly lower than in the control group SK. The SH4 group was characterized by a significantly lower diastolic blood pressure value and concentration of TNF-α in comparison to the SK group. The rats from both SH2 and SH4 groups were characterized by higher total antioxidant status values compared to the control group. Discussion: The mechanism of the beneficial effects of green tea on blood pressure is not clear, but it is believed that it is related to its omnidirectional properties. Conclusions: Supplementation of green tea has a beneficial effect on blood pressure, markers of inflammation and antioxidant status in an experimental model of hypertension. PMID:28326006

  7. Defibrillator Implantation in Patients with Nonischemic Systolic Heart Failure

    DEFF Research Database (Denmark)

    Køber, Lars; Thune, Jens J; Nielsen, Jens C

    2016-01-01

    BACKGROUND: The benefit of an implantable cardioverter-defibrillator (ICD) in patients with symptomatic systolic heart failure caused by coronary artery disease has been well documented. However, the evidence for a benefit of prophylactic ICDs in patients with systolic heart failure that is not d...... by Medtronic and others; DANISH ClinicalTrials.gov number, NCT00542945 .)....

  8. Exercise training in older patients with systolic heart failure

    DEFF Research Database (Denmark)

    Prescott, Eva; Hjardem-Hansen, Rasmus; Dela, Flemming

    2009-01-01

    Training improves exercise capacity in patients with heart failure (CHF) but most evidence is on selected younger patients with systolic CHF.......Training improves exercise capacity in patients with heart failure (CHF) but most evidence is on selected younger patients with systolic CHF....

  9. Central Systolic Hypertension in Patients with Well-Controlled Hypertension

    Science.gov (United States)

    Potočárová, Mária; Murín, Ján; Kozlíková, Katarína; Luha, Ján; Čaprnda, Martin

    2017-01-01

    Background. Central systolic blood pressure (CSBP) has prognostic significance and simplified devices for its estimation have been introduced recently. The aim of this study was to assess the achievement of the target CSBP in treated hypertensive patients. Subjects and Methods. One hundred patients with well-controlled hypertension were analysed. For CSBP estimation, we used the Arteriograph (TensioMed Ltd.), which uses one cuff for all measurements, the “single-point measurement” approach. Results. We found that 62% of patients had CSBP ≥ 130 mmHg, the suggested cut-off value for hypertension. When sex-specific classification was employed (CSBP ≥ 137 mmHg for female and CSBP ≥ 133 mmHg for male), only 13% of patients (mainly women) remained in the hypertensive range. We also found that 55% of patients had a CSBP higher than brachial pressure. Multiple analyses showed that CSBP was significantly associated with sex, height, and return time. Conclusions. A high proportion of treated hypertensive patients had CSBP levels that exceeded their brachial BP. CSBP positively correlated with lower height and shorter return time of the reflected pressure wave and was significantly higher in females compared to males. These findings suggest that, for CSBP classification, it is important to take height and sex-specific differences into account. PMID:28127560

  10. 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.

  11. Methyl mercury, but not inorganic mercury, associated with higher blood pressure during pregnancy.

    Science.gov (United States)

    Wells, Ellen M; Herbstman, Julie B; Lin, Yu Hong; Hibbeln, Joseph R; Halden, Rolf U; Witter, Frank R; Goldman, Lynn R

    2017-04-01

    Prior studies addressing associations between mercury and blood pressure have produced inconsistent findings; some of this may result from measuring total instead of speciated mercury. This cross-sectional study of 263 pregnant women assessed total mercury, speciated mercury, selenium, and n-3 polyunsaturated fatty acids in umbilical cord blood and blood pressure during labor and delivery. Models with a) total mercury or b) methyl and inorganic mercury were evaluated. Regression models adjusted for maternal age, race/ethnicity, prepregnancy body mass index, neighborhood income, parity, smoking, n-3 fatty acids and selenium. Geometric mean total, methyl, and inorganic mercury concentrations were 1.40µg/L (95% confidence interval: 1.29, 1.52); 0.95µg/L (0.84, 1.07); and 0.13µg/L (0.10, 0.17), respectively. Elevated systolic BP, diastolic BP, and pulse pressure were found, respectively, in 11.4%, 6.8%, and 19.8% of mothers. In adjusted multivariable models, a one-tertile increase of methyl mercury was associated with 2.83mmHg (0.17, 5.50) higher systolic blood pressure and 2.99mmHg (0.91, 5.08) higher pulse pressure. In the same models, an increase of one tertile of inorganic mercury was associated with -1.18mmHg (-3.72, 1.35) lower systolic blood pressure and -2.51mmHg (-4.49, -0.53) lower pulse pressure. No associations were observed with diastolic pressure. There was a non-significant trend of higher total mercury with higher systolic blood pressure. We observed a significant association of higher methyl mercury with higher systolic and pulse pressure, yet higher inorganic mercury was significantly associated with lower pulse pressure. These results should be confirmed with larger, longitudinal studies.

  12. [Analysis on establishment and affecting factors of qi stagnation and blood stasis rat model].

    Science.gov (United States)

    Wang, Tingting; Jia, Cheng; Chen, Yu; Li, Xin; Cheng, Jiayi

    2012-06-01

    To study on the method for establishing the Qi stagnation and blood stasis rat model and analyze the affecting factors. The orthogonal design was adopted to study the influences of joint stimulations including noise, light, electricity, ice water bath, tail-clamping on model rats. The 'flying spot' method was used to dynamically simulate blood flow velocity in microcirculation. the pressure sensing technology of MOTO was adopted to detect hemorheology-related indicators. And the coagulation method was used to detect blood coagulation-related indicators. Compared with the negative control group, all model groups showed significant reduction in the blood flow velocity in mesenteric microcirculation and increase in the whole blood viscosity at high, medium and low shear rate, the plasma viscosity and the fibrinogen content in four blood coagulation indicators. Noise, light, electricity, tail-clamping, bondage and icewater-bath make significant impact on model rats.

  13. Biological consequences of stress: conflicting findings on the association between job strain and blood pressure.

    Science.gov (United States)

    Fornari, C; Ferrario, M; Menni, C; Sega, R; Facchetti, R; Cesana, G C

    2007-11-01

    The primary objective is to verify the relation between job strain and clinic blood pressure in a working population from the Milan municipality (1,909 men, 3,786 women) enrolled from 1992 to 1996. Job strain was investigated through the Karasek model. Clinic blood pressure was evaluated using standard procedures from the MONICA project. The association between the two was calculated controlling for age, education, smoking, body mass index, total and high-density lipoprotein (HDL) cholesterol. Significantly, associations were found for systolic blood pressure in men and for both systolic and diastolic blood pressure in women. However, these results do not reflect biological plausibility. The relationship between job strain and blood pressure is an unfinished business: sample characteristics and measurement methods should be carefully considered.

  14. Systolic array IC for genetic computation

    Science.gov (United States)

    Anderson, D.

    1991-01-01

    Measuring similarities between large sequences of genetic information is a formidable task requiring enormous amounts of computer time. Geneticists claim that nearly two months of CRAY-2 time are required to run a single comparison of the known database against the new bases that will be found this year, and more than a CRAY-2 year for next year's genetic discoveries, and so on. The DNA IC, designed at HP-ICBD in cooperation with the California Institute of Technology and the Jet Propulsion Laboratory, is being implemented in order to move the task of genetic comparison onto workstations and personal computers, while vastly improving performance. The chip is a systolic (pumped) array comprised of 16 processors, control logic, and global RAM, totaling 400,000 FETS. At 12 MHz, each chip performs 2.7 billion 16 bit operations per second. Using 35 of these chips in series on one PC board (performing nearly 100 billion operations per second), a sequence of 560 bases can be compared against the eventual total genome of 3 billion bases, in minutes--on a personal computer. While the designed purpose of the DNA chip is for genetic research, other disciplines requiring similarity measurements between strings of 7 bit encoded data could make use of this chip as well. Cryptography and speech recognition are two examples. A mix of full custom design and standard cells, in CMOS34, were used to achieve these goals. Innovative test methods were developed to enhance controllability and observability in the array. This paper describes these techniques as well as the chip's functionality. This chip was designed in the 1989-90 timeframe.

  15. A Computational Model Predicting Disruption of Blood Vessel Development

    Science.gov (United States)

    Vascular development is a complex process regulated by dynamic biological networks that vary in topology and state across different tissues and developmental stages. Signals regulating de novo blood vessel formation (vasculogenesis) and remodeling (angiogenesis) come from a varie...

  16. Modeling Blood Pressure:Comparative Study Of Seemingly ...

    African Journals Online (AJOL)

    persons engaged in occupations involving little physical activity than those who are more active (Mial, 1959;. Idahosa, 1987). ..... prevalence and biosocial determinants of high blood pressure in a group of urban Nigerians. J. Hum Hypertens.

  17. THE BLOOD PRESSURE AMONG HIGH RISK PILGRIMS OF KLOTER 30 BEKASI, YEAR 2003 BEFORE DEPARTURE IN INDONESIA AND AFTER UMRAH IN MECCA

    Directory of Open Access Journals (Sweden)

    Betty Roosihermiatie

    2012-11-01

    Full Text Available The main cause of mortality among Indonesian pilgrims was circulatory diseases. The death was common among old pilgrims, especially due to heart failure. It is known that hypertension is one of the causes of heart failure The study aimed to determine blood pressures among high risk pilgrims after umrah in Mecca, Saudi Arabia and blood pressure in Indonesia with influencing factors: sex, body mass index, accommodation room density, and number of condition/diseases.It was an observational study. Twenty eight high risk pilgrims of kelompok terbang (kloter or flight group 30 JKS year 2003 were voluntarily participated in the study. The blood pressure of the respondents was measured at sitting position. Mean differences of systolic and diastolic blood pressure in Indonesia and after umrah was compared by paired t-test. Systolic blood pressure in Indonesia after umrah, by controlling confounding variables was analyzed by linear regression model. The systolic blood pressure of respondents after umrah tended to decrease to 0.43 mm Hg in comparison to 1 mmHg increase on examination in Indonesia, at number of conditions/diseases to be constant. It is likely that the psychological sincerity (ikhlas has influenced the decrease of sympathetic intervations system in brainstem for blood pressure to lower of systolic blood pressure. Meanwhile, the systolic blood pressure after umrah tended to increase to 11.94 mmHg for a number of conditions/diseases to be constant. The pilgrimage activities is hard, especially in surrounding higher climate at the average of 39• C. So pilgrims with the condition as old people or having diseases influenced the systolic blood pressure. The peripheral vasoconstriction possibly caused increase systolic blood pressure. Pilgrimage is a hard physical activity, more over for high risk pilgrims. Hence, monitoring pilgrim health conditions, especially the high risk pilgnms, should be conducted by kloter health workers, like to control

  18. Statistical analysis of simulation-generated time series : Systolic vs. semi-systolic correlation on the Connection Machine

    NARCIS (Netherlands)

    Dontje, T.; Lippert, Th.; Petkov, N.; Schilling, K.

    1992-01-01

    Autocorrelation becomes an increasingly important tool to verify improvements in the state of the simulational art in Latice Gauge Theory. Semi-systolic and full-systolic algorithms are presented which are intensively used for correlation computations on the Connection Machine CM-2. The semi-systoli

  19. Statistical analysis of simulation-generated time series : Systolic vs. semi-systolic correlation on the Connection Machine

    NARCIS (Netherlands)

    Dontje, T.; Lippert, Th.; Petkov, N.; Schilling, K.

    1992-01-01

    Autocorrelation becomes an increasingly important tool to verify improvements in the state of the simulational art in Latice Gauge Theory. Semi-systolic and full-systolic algorithms are presented which are intensively used for correlation computations on the Connection Machine CM-2. The

  20. Worldwide trends in blood pressure from 1975 to 2015

    NARCIS (Netherlands)

    Ezzati, Majid; Geleijnse, J.M.

    2017-01-01

    Background

    Raised blood pressure is an important risk factor for cardiovascular diseases and chronic kidney disease. We estimated worldwide trends in mean systolic and mean diastolic blood pressure, and the prevalence of, and number of people with, raised blood pressure, defined as systolic

  1. Significance of White-Coat Hypertension in Older Persons With Isolated Systolic Hypertension

    Science.gov (United States)

    Franklin, Stanley S.; Thijs, Lutgarde; Hansen, Tine W.; Li, Yan; Boggia, José; Kikuya, Masahiro; Björklund-Bodegård, Kristina; Ohkubo, Takayoshi; Jeppesen, Jørgen; Torp-Pedersen, Christian; Dolan, Eamon; Kuznetsova, Tatiana; Stolarz-Skrzypek, Katarzyna; Tikhonoff, Valérie; Malyutina, Sofia; Casiglia, Edoardo; Nikitin, Yuri; Lind, Lars; Sandoya, Edgardo; Kawecka-Jaszcz, Kalina; Imai, Yutaka; Wang, Jiguang; Ibsen, Hans; O’Brien, Eoin; Staessen, Jan A.

    2013-01-01

    The significance of white-coat hypertension in older persons with isolated systolic hypertension remains poorly understood. We analyzed subjects from the population-based 11-country International Database on Ambulatory Blood Pressure Monitoring in Relation to Cardiovascular Outcomes database who had daytime ambulatory blood pressure (BP; ABP) and conventional BP (CBP) measurements. After excluding persons with diastolic hypertension by CBP (≥90 mm Hg) or by daytime ABP (≥85 mm Hg), a history of cardiovascular disease, and persons hypertension. During a median follow-up of 10.6 years, there was a total of 655 fatal and nonfatal cardiovascular events. The analyses were stratified by treatment status. In untreated subjects, those with white-coat hypertension (CBP ≥140/hypertension, the cardiovascular risk was similar in elevated conventional and normal daytime systolic BP as compared with those with normal conventional and normal daytime BPs (adjusted hazard rate: 1.10 [95% CI: 0.79–1.53]; P=0.57). However, both treated isolated systolic hypertension subjects with white-coat hypertension (adjusted hazard rate: 2.00; [95% CI: 1.43–2.79]; Phypertension who have their ABP normalized on antihypertensive therapy but with residual white-coat effect by CBP measurement have an entity that we have termed, “treated normalized hypertension.” Therefore, one should be cautious in applying the term “white-coat hypertension” to persons receiving antihypertensive treatment. PMID:22252396

  2. Saving the leftovers: models for banking cord blood stem cells.

    Science.gov (United States)

    Cogdell, Kimberly J

    2009-01-01

    Each year there are over four million live births in the United States. Each birth produces umbilical cord blood stem cells, which are usually discarded. The author argues that rather than discarding the umbilical cord, this valuable resource of cord blood should be banked and used for research and therapeutic purposes. Umbilical cord blood could provide a solution to the critical need to find matching donors for hematopoietic transplants in patients who have no matching bone marrow donors. Creating a system of universal donation to a public bank will greatlyincrease the number of donors and therefore, the number of matches for patients. Such a system will facilitate the development and use of new technologies and transplant procedures, while providing an opportunity for treatment to individuals who would otherwise not be able to find suitable donors.

  3. AN ANALYSIS MODEL OF PULSATILE BLOOD FLOW IN ARTERIES

    Institute of Scientific and Technical Information of China (English)

    LIUZhao-rong; XUGang; CHENYong; TENGZhong0=zhao; QINKai-rong

    2003-01-01

    Blood flow in artery was treated as the flow under equilibriums state(the steady flow under mean pressure)combined with the periodically small pulsatile flow.Using vascular strain energy function advanced by Fung,the vascular stress-strain relationship under equilibrium state was analyzed and the circumferential and axial elastic moduli were deduced that are expressed while the arterial strains around the equilibrium state are relatively small,so that the equations of vesse wall motion under the pulsatile pressure could be established here.Through solving both the vessel equations and the linear Navier-Stokes equations,the analytic expressions of the blood flow velocities and the vascular displacements were obtained.The influence of the difference between vascular circumferentia and axial elasticities on pulsatile blood flow and vascular motion was discussed in details.

  4. AN ANALYSIS MODEL OF PULSATILE BLOOD FLOW IN ARTERIES

    Institute of Scientific and Technical Information of China (English)

    柳兆荣; 徐刚; 陈泳; 滕忠照; 覃开蓉

    2003-01-01

    Blood flow in artery was treated as the flow under equilibrium state ( the steady flow under mean pressure ) combined with the periodically small pulsatile flow. Using vascular strain energy function advanced by Fung, the vascular stress-strain relationship under equilibrium state was analyzed and the circumferential and axial elastic moduli were deduced that are expressed while the arterial strains around the equilibrium state are relatively small, so that the equations of vessel wall motion under the pulsatile pressure could be established here. Through solving both the vessel equations and the linear NavierStokes equations, the analytic expressions of the blood flow velocities and the vascular displacements were obtained. The influence of the difference between vascular circumferential and axial elasticities on pulsatile blood flow and vascular motion was discussed in details.

  5. Effect of magnesium supplementation on blood pressure and vascular reactivity in nitric oxide synthase inhibition-induced hypertension model.

    Science.gov (United States)

    Basralı, Filiz; Koçer, Günnur; Ülker Karadamar, Pınar; Nasırcılar Ülker, Seher; Satı, Leyla; Özen, Nur; Özyurt, Dilek; Şentürk, Ümit Kemal

    2015-01-01

    The aim of this study was to assess the effect of oral magnesium supplementation (Mg-supp) on blood pressure (BP) and possible mechanism in nitric oxide synthase (NOS) inhibition-induced hypertension model. Hypertension and/or Mg-supp were created by N-nitro-l-arginine methyl ester (25 mg/kg/day by drinking water) and magnesium-oxide (0.8% by diet) for 6 weeks. Systolic BP was measured weekly by tail-cuff method. The effects of hypertension and/or Mg-supp in thoracic aorta and third branch of mesenteric artery constriction and relaxation responses were evaluated. NOS-inhibition produced a gradually developing hypertension and the magnitude of the BP was significantly attenuated after five weeks of Mg-supp. The increased phenylephrine-induced contractile and decreased acetylcholine (ACh)-induced dilation responses were found in both artery segments of hypertensive groups. Mg-supp was restored ACh-relaxation response in both arterial segments and also Phe-constriction response in thoracic aorta but not in mesenteric arteries. The contributions of NO, prostaglandins and K(+) channels to the dilator response of ACh were similar in the aorta of all the groups. The contribution of the NO to the ACh-mediated relaxation response of mesenteric arteries was suppressed in hypertensive rats, whereas this was corrected by Mg-supp. The flow-mediated dilation response of mesenteric arteries in hypertensive rats failed and could not be corrected by Mg-supp. Whereas, vascular eNOS protein and magnesium levels were not changed and plasma nitrite levels were reduced in hypertensive rats. The results of this study showed that Mg-supp lowered the arterial BP in NOS-inhibition induced hypertension model by restoring the agonist-induced relaxation response of the arteries.

  6. Modeling cerebral blood flow during posture change from sitting to standing

    DEFF Research Database (Denmark)

    Ottesen, Johnny T.; Olufsen, M.; Tran, H.T.

    2004-01-01

    extremities, the brain, and the heart. We use physiologically based control mechanisms to describe the regulation of cerebral blood flow velocity and arterial pressure in response to orthostatic hypotension resulting from postural change. To justify the fidelity of our mathematical model and control......Abstract Hypertension, decreased cerebral blood flow, and diminished cerebral blood flow velocity regulation, are among the first signs indicating the presence of cerebral vascular disease. In this paper, we will present a mathematical model that can predict blood flow and pressure during posture...

  7. Magnetic field effect on blood flow of Casson fluid in axisymmetric cylindrical tube: A fractional model

    Science.gov (United States)

    Ali, Farhad; Sheikh, Nadeem Ahmad; Khan, Ilyas; Saqib, Muhammad

    2017-02-01

    The effects of magnetohydrodynamics on the blood flow when blood is represented as a Casson fluid, along with magnetic particles in a horizontal cylinder is studied. The flow is due to an oscillating pressure gradient. The Laplace and finite Hankel transforms are used to obtain the closed form solutions of the fractional partial differential equations. Effects of various parameters on the flow of both blood and magnetic particles are shown graphically. The analysis shows that, the model with fractional order derivatives bring a remarkable changes as compared to the ordinary model. The study highlights that applied magnetic field reduces the velocities of both the blood and magnetic particles.

  8. Walking speed and high blood pressure mortality risk in a Spanish elderly population.

    Science.gov (United States)

    Gutiérrez-Misis, A; Sánchez-Santos, M T; Banegas, J R; Castell, M V; González-Montalvo, J I; Otero, A

    2015-09-01

    This study analyzed the relationship between blood pressure and all-cause mortality according to objectively measured walking speed in a Mediterranean population-based sample of older persons. We used data from the longitudinal 'Peñagrande' Cohort Study, initiated in 2008 in a sex- and age-stratified random sample of 1250 people aged ⩾65 years living in Madrid (Spain). A total of 814 individuals participated in the first study wave. The average of two standardized blood pressure readings was used. Walking speed was measured over a 3-m walk and classified as faster (⩾0.8 m s(-1)) or slower. A total of 314 individuals were slower walkers, 475 were faster walkers and 25 did not complete the walk test. Cox proportional hazards models stratified by walking speed were used to assess the association between blood pressure and all-cause death. Non-linear relationship between BP and mortality was explored by a restricted cubic spline analysis. There were 171 deaths from study entry through 31 March 2013. Systolic blood pressure blood pressure blood pressure values above 140 and 90 mm Hg, respectively, but this association reached statistical significance only for systolic blood pressure and only in the slower walkers. In conclusion, systolic blood pressure levels risk of total mortality among slower walkers in an old Spaniard population cohort.

  9. Isolated systolic hypertension in young and middle-aged adults and 31-year risk for cardiovascular mortality: the Chicago Heart Association Detection Project in Industry study.

    Science.gov (United States)

    Yano, Yuichiro; Stamler, Jeremiah; Garside, Daniel B; Daviglus, Martha L; Franklin, Stanley S; Carnethon, Mercedes R; Liu, Kiang; Greenland, Philip; Lloyd-Jones, Donald M

    2015-02-03

    Isolated systolic hypertension (ISH), defined as systolic blood pressure (SBP) ≥140 mm Hg and diastolic blood pressure (DBP) adults is increasing in prevalence. The aim of this study was to assess the risk for cardiovascular disease (CVD) with ISH in younger and middle-aged adults. CVD risks were explored in 15,868 men and 11,213 women 18 to 49 years of age (mean age 34 years) at baseline, 85% non-Hispanic white, free of coronary heart disease (CHD) and antihypertensive therapy, from the Chicago Heart Association Detection Project in Industry study. Participant classifications were as follows: 1) optimal-normal blood pressure (BP) (SBP hypertension (SBP hypertension (SBP ≥140 mm Hg and DBP ≥90 mm Hg). During a 31-year average follow-up period (842,600 person-years), there were 1,728 deaths from CVD, 1,168 from CHD, and 223 from stroke. Cox proportional hazards models were adjusted for age, race, education, body mass index, current smoking, total cholesterol, and diabetes. In men, with optimal-normal BP as the reference stratum, hazard ratios for CVD and CHD mortality risk for those with ISH were 1.23 (95% confidence interval [CI]: 1.03 to 1.46) and 1.28 (95% CI: 1.04 to 1.58), respectively. ISH risks were similar to those with high-normal BP and less than those associated with isolated diastolic hypertension and systolic diastolic hypertension. In women with ISH, hazard ratios for CVD and CHD mortality risk were 1.55 (95% CI: 1.18 to 2.05) and 2.12 (95% CI: 1.49 to 3.01), respectively. ISH risks were higher than in those with high-normal BP or isolated diastolic hypertension and less than those associated with systolic diastolic hypertension. Over long-term follow-up, younger and middle-aged adults with ISH had higher relative risk for CVD and CHD mortality than those with optimal-normal BP. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. A robust optimization model for blood supply chain in emergency situations

    Directory of Open Access Journals (Sweden)

    Meysam Fereiduni

    2016-09-01

    Full Text Available In this paper, a multi-period model for blood supply chain in emergency situation is presented to optimize decisions related to locate blood facilities and distribute blood products after natural disasters. In disastrous situations, uncertainty is an inseparable part of humanitarian logistics and blood supply chain as well. This paper proposes a robust network to capture the uncertain nature of blood supply chain during and after disasters. This study considers donor points, blood facilities, processing and testing labs, and hospitals as the components of blood supply chain. In addition, this paper makes location and allocation decisions for multiple post disaster periods through real data. The study compares the performances of “p-robust optimization” approach and “robust optimization” approach and the results are discussed.

  11. Theoretical models for near forward light scattering by a Plasmodium falciparum infected red blood cell

    Science.gov (United States)

    Sharma, S. K.

    2012-12-01

    A number of experimental elastic light scattering studies have been performed in the past few years with the aim of developing automated in vivo tools for differentiating a healthy red blood cell from a Plasmodium falciparum infected cell. This paper examines some theoretical aspects of the problem. An attempt has been made to simulate the scattering patterns of healthy as well as infected individual red blood cells. Two models, namely, a homogeneous sphere model and a coated sphere model have been considered. The scattering patterns predicted by these models are examined. A possible method for discriminating infected red blood cells from healthy ones has been suggested.

  12. Blood Vessel Normalization in the Hamster Oral Cancer Model for Experimental Cancer Therapy Studies

    Energy Technology Data Exchange (ETDEWEB)

    Ana J. Molinari; Romina F. Aromando; Maria E. Itoiz; Marcela A. Garabalino; Andrea Monti Hughes; Elisa M. Heber; Emiliano C. C. Pozzi; David W. Nigg; Veronica A. Trivillin; Amanda E. Schwint

    2012-07-01

    Normalization of tumor blood vessels improves drug and oxygen delivery to cancer cells. The aim of this study was to develop a technique to normalize blood vessels in the hamster cheek pouch model of oral cancer. Materials and Methods: Tumor-bearing hamsters were treated with thalidomide and were compared with controls. Results: Twenty eight hours after treatment with thalidomide, the blood vessels of premalignant tissue observable in vivo became narrower and less tortuous than those of controls; Evans Blue Dye extravasation in tumor was significantly reduced (indicating a reduction in aberrant tumor vascular hyperpermeability that compromises blood flow), and tumor blood vessel morphology in histological sections, labeled for Factor VIII, revealed a significant reduction in compressive forces. These findings indicated blood vessel normalization with a window of 48 h. Conclusion: The technique developed herein has rendered the hamster oral cancer model amenable to research, with the potential benefit of vascular normalization in head and neck cancer therapy.

  13. Comparison of reduced models for blood flow using Runge-Kutta discontinuous Galerkin methods

    CERN Document Server

    Puelz, Charles; Canic, Suncica; Rusin, Craig G

    2015-01-01

    Reduced, or one-dimensional blood flow models take the general form of nonlinear hyperbolic systems, but differ greatly in their formulation. One class of models considers the physically conserved quantities of mass and momentum, while another class describes mass and velocity. Further, the averaging process employed in the model derivation requires the specification of the axial velocity profile; this choice differentiates models within each class. Discrepancies among differing models have yet to be investigated. In this paper, we systematically compare several reduced models of blood flow for physiologically relevant vessel parameters, network topology, and boundary data. The models are discretized by a class of Runge-Kutta discontinuous Galerkin methods.

  14. Defibrillator Implantation in Patients with Nonischemic Systolic Heart Failure

    DEFF Research Database (Denmark)

    Køber, Lars; Thune, Jens J; Nielsen, Jens C

    2016-01-01

    BACKGROUND: The benefit of an implantable cardioverter-defibrillator (ICD) in patients with symptomatic systolic heart failure caused by coronary artery disease has been well documented. However, the evidence for a benefit of prophylactic ICDs in patients with systolic heart failure that is not due.......6%) in the control group (P=0.29). CONCLUSIONS: In this trial, prophylactic ICD implantation in patients with symptomatic systolic heart failure not caused by coronary artery disease was not associated with a significantly lower long-term rate of death from any cause than was usual clinical care. (Funded...... to coronary artery disease has been based primarily on subgroup analyses. The management of heart failure has improved since the landmark ICD trials, and many patients now receive cardiac resynchronization therapy (CRT). METHODS: In a randomized, controlled trial, 556 patients with symptomatic systolic heart...

  15. A Comprehensive Fluid Dynamic-Diffusion Model of Blood Microcirculation with Focus on Sickle Cell Disease

    Science.gov (United States)

    Le Floch, Francois; Harris, Wesley L.

    2009-11-01

    A novel methodology has been developed to address sickle cell disease, based on highly descriptive mathematical models for blood flow in the capillaries. Our investigations focus on the coupling between oxygen delivery and red blood cell dynamics, which is crucial to understanding sickle cell crises and is unique to this blood disease. The main part of our work is an extensive study of blood dynamics through simulations of red cells deforming within the capillary vessels, and relies on the use of a large mathematical system of equations describing oxygen transfer, blood plasma dynamics and red cell membrane mechanics. This model is expected to lead to the development of new research strategies for sickle cell disease. Our simulation model could be used not only to assess current researched remedies, but also to spur innovative research initiatives, based on our study of the physical properties coupled in sickle cell disease.

  16. Severe systolic hypertension and the search for safer motherhood.

    Science.gov (United States)

    Martin, James N

    2016-03-01

    Timely and appropriate response to severe hypertension during gestation is an important component of quality, safe care for pregnant or puerperal mothers regardless of causation. The reduction of severe maternal morbidity and maternal mortality in the hypertensive mother is clearly enhanced by the addition of standard protocols for provider response to severe hypertension, particularly severe systolic hypertension. The program developed in New York State via the Safe Motherhood Initiative promotes the implementation of unit-specific safety bundles, especially one that is focused upon a standardized approach to handling the obstetric emergency of severe hypertension usually associated with preeclampsia/eclampsia. The comprehensive preeclampsia/eclampsia safety bundle as summarized by Drs. Moroz and colleagues is reviewed especially from the perspective of its focus on the timely and specific responses for health care providers to make when severe hypertension is detected in the pregnant patient. Evidence-based guidance to practice considerations and clinical care of patients with preeclampsia/eclampsia is embedded within the program outlined for New York State by Moroz and her District II ACOG colleagues. There is a central focus on timely and appropriate antepartum/postpartum management of severe hypertension, a core concept to lessen maternal risk for cerebral hemorrhage. Ten considerations for further integration into the New York program are suggested. Beyond blood pressure control, there is a need for systematic review of interventions and outcomes over time, attention to possible future variations of the protocol for racial/ethnic patient groups at highest risk for maternal morbidity and mortality, and the identification of biomarker(s) that further specify and quantify risk to the maternal brain and other organ systems when severe hypertension develops. Safer motherhood will happen when evidence for best practice is integrated into systems of care for all

  17. A novel, minimally invasive rat model of normothermic cardiopulmonary bypass model without blood priming

    Institute of Scientific and Technical Information of China (English)

    Zhu Yaobin; Liu Donghai; Li Xiaofeng; Liu Aijun; Wang Qiang; Qiao Chenhui; Zhang Jing

    2014-01-01

    Background Cardiopulmonary bypass (CPB) has been shown to be associated with systemic inflammatory response leading to postoperative organ dysfunction.Elucidating the underlying mechanisms and developing protective strategies for the pathophysiological consequences of CPB have been hampered due to the absence of a satisfactory recovery animal model.The purpose of this study was to establish a novel,minimally invasive rat model of normothermic CPB model without blood priming.Methods Twenty adult male Sprague-Dawley rats weighing 450-560 g were randomly divided into CPB group (n=10) and control group (n=10).All rats were anaesthetized and mechanically ventilated.The carotid artery and jugular vein were cannulated.The blood was drained from the right atrium via the right jugular and further transferred by a miniaturized roller pump to a hollow fiber oxygenator and back to the rat via the left carotid artery.The volume of the priming solution,composed of 6% HES130/0.4 and 125 IU heparin,was less than 12 ml.The surface of the hollow fiber oxygenator was 0.075 m2.CPB was conducted for 60 minutes at a flow rat of 100-120 ml· kg-1· min-1 in CPB group.Oxygen flow/perfusion flow was 0.8 to 1.0,and the mean arterial pressure remained 60-80 mmHg.Results All CPB processes were successfully achieved.Blood gas analysis and hemodynamic parameters of each time point were in accordance with normal ranges.The vital signs of all rats were stable.Conclusions The establishment of CPB without blood priming in rats can be achieved successfully.The nontransthoracic model should facilitate the investigation of pathophysiological processes concerning CPB-related multiple organ dysfunction and possible protective interventions.This novel,recovery,and reproducible minimally invasive CPB model may open the field for various studies on the pathophysiological process of CPB and systemic ischemia-reperfusion injury in vivo.

  18. Computational Fluid Dynamics Analysis of Pulsatile Blood Flow Behavior in Modelled Stenosed Vessels with Different Severities

    Directory of Open Access Journals (Sweden)

    Mohsen Mehrabi

    2012-01-01

    Full Text Available This study focuses on the behavior of blood flow in the stenosed vessels. Blood is modelled as an incompressible non-Newtonian fluid which is based on the power law viscosity model. A numerical technique based on the finite difference method is developed to simulate the blood flow taking into account the transient periodic behaviour of the blood flow in cardiac cycles. Also, pulsatile blood flow in the stenosed vessel is based on the Womersley model, and fluid flow in the lumen region is governed by the continuity equation and the Navier-Stokes equations. In this study, the stenosis shape is cosine by using Tu and Devil model. Comparing the results obtained from three stenosed vessels with 30%, 50%, and 75% area severity, we find that higher percent-area severity of stenosis leads to higher extrapressure jumps and higher blood speeds around the stenosis site. Also, we observe that the size of the stenosis in stenosed vessels does influence the blood flow. A little change on the cross-sectional value makes vast change on the blood flow rate. This simulation helps the people working in the field of physiological fluid dynamics as well as the medical practitioners.

  19. Differences in iron concentration in whole blood of animal models using NAA

    Science.gov (United States)

    Bahovschi, V.; Zamboni, C. B.; Lopes Silva, L. F. F.; Metairon, S.; Medeiros, I. M. M. A.

    2015-07-01

    In this study Neutron Activation Analysis technique (NAA) was applied to determine Fe concentration in whole blood samples of several animal models such as: mice (Mus musculus), Golden Hamster (Mesocricetus auratus), Wistar rats, Albinic Rabbits of New Zealand, Golden Retriever dogs and Crioulabreed horses. These results were compared with human whole blood estimation to check their similarities.

  20. Viscoelastic behaviour of human blood and polyacrylamide model fluids for heart valve testing

    Science.gov (United States)

    Lerche, Dietmar; Vlastos, Georgios; Koch, Brigitte; Pohl, Manfred; Affeld, Klaus

    1993-06-01

    New heart valves and other cardiovascular assist systems have to be tested for hydrodynamic performance. In place of human blood simple model fluids like glycerol solutions are employed often due to ethical and practical reasons. But blood exhibits complex non-Newtonian and viscoelastic behaviour. Rheological blood properties are reviewed based on literature and own experimental results. Furthermore we studied polymer solutions with respect to blood-like flow behaviour. Rheology was assessed by means of the low shear rotational viscometer (LS 40, Mettler-Toledo, Switzerland) under stationary and dynamic shear conditions (variation of frequency and angular displacement).

  1. Exploring the Impact of Students' Learning Approach on Collaborative Group Modeling of Blood Circulation

    Science.gov (United States)

    Lee, Shinyoung; Kang, Eunhee; Kim, Heui-Baik

    2015-01-01

    This study aimed to explore the effect on group dynamics of statements associated with deep learning approaches (DLA) and their contribution to cognitive collaboration and model development during group modeling of blood circulation. A group was selected for an in-depth analysis of collaborative group modeling. This group constructed a model in a…

  2. A comprehensive compartmental model of blood glucose regulation for healthy and type 2 diabetic subjects

    DEFF Research Database (Denmark)

    Vahidi, O; Kwok, K E; Gopaluni, R B

    2016-01-01

    We have expanded a former compartmental model of blood glucose regulation for healthy and type 2 diabetic subjects. The former model was a detailed physiological model which considered the interactions of three substances, glucose, insulin and glucagon on regulating the blood sugar. The main...... drawback of the former model was its restriction on the route of glucose entrance to the body which was limited to the intravenous glucose injection. To handle the oral glucose intake, we have added a model of glucose absorption in the gastrointestinal tract to the former model to address the resultant...... variations of blood glucose concentrations following an oral glucose intake. Another model representing the incretins production in the gastrointestinal tract along with their hormonal effects on boosting pancreatic insulin production is also added to the former model. We have used two sets of clinical data...

  3. Parameterizing the Morse potential for coarse-grained modeling of blood plasma

    Science.gov (United States)

    Zhang, Na; Zhang, Peng; Kang, Wei; Bluestein, Danny; Deng, Yuefan

    2014-01-01

    Multiscale simulations of fluids such as blood represent a major computational challenge of coupling the disparate spatiotemporal scales between molecular and macroscopic transport phenomena characterizing such complex fluids. In this paper, a coarse-grained (CG) particle model is developed for simulating blood flow by modifying the Morse potential, traditionally used in Molecular Dynamics for modeling vibrating structures. The modified Morse potential is parameterized with effective mass scales for reproducing blood viscous flow properties, including density, pressure, viscosity, compressibility and characteristic flow dynamics of human blood plasma fluid. The parameterization follows a standard inverse-problem approach in which the optimal micro parameters are systematically searched, by gradually decoupling loosely correlated parameter spaces, to match the macro physical quantities of viscous blood flow. The predictions of this particle based multiscale model compare favorably to classic viscous flow solutions such as Counter-Poiseuille and Couette flows. It demonstrates that such coarse grained particle model can be applied to replicate the dynamics of viscous blood flow, with the advantage of bridging the gap between macroscopic flow scales and the cellular scales characterizing blood flow that continuum based models fail to handle adequately.

  4. Parameterizing the Morse potential for coarse-grained modeling of blood plasma

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Na [Department of Applied Mathematics and Statistics, Stony Brook University, NY 11794 (United States); Zhang, Peng [Department of Biomedical Engineering, Stony Brook University, NY 11790 (United States); Kang, Wei [Center for Applied Physics and Technology, College of Engineering, Peking University, Beijing 100871 (China); Bluestein, Danny [Department of Biomedical Engineering, Stony Brook University, NY 11790 (United States); Deng, Yuefan, E-mail: Yuefan.Deng@StonyBrook.edu [Department of Applied Mathematics and Statistics, Stony Brook University, NY 11794 (United States)

    2014-01-15

    Multiscale simulations of fluids such as blood represent a major computational challenge of coupling the disparate spatiotemporal scales between molecular and macroscopic transport phenomena characterizing such complex fluids. In this paper, a coarse-grained (CG) particle model is developed for simulating blood flow by modifying the Morse potential, traditionally used in Molecular Dynamics for modeling vibrating structures. The modified Morse potential is parameterized with effective mass scales for reproducing blood viscous flow properties, including density, pressure, viscosity, compressibility and characteristic flow dynamics of human blood plasma fluid. The parameterization follows a standard inverse-problem approach in which the optimal micro parameters are systematically searched, by gradually decoupling loosely correlated parameter spaces, to match the macro physical quantities of viscous blood flow. The predictions of this particle based multiscale model compare favorably to classic viscous flow solutions such as Counter-Poiseuille and Couette flows. It demonstrates that such coarse grained particle model can be applied to replicate the dynamics of viscous blood flow, with the advantage of bridging the gap between macroscopic flow scales and the cellular scales characterizing blood flow that continuum based models fail to handle adequately.

  5. Repeated heart rate measurement and cardiovascular outcomes in left ventricular systolic dysfunction.

    Science.gov (United States)

    Hamill, Victoria; Ford, Ian; Fox, Kim; Böhm, Michael; Borer, Jeffrey S; Ferrari, Roberto; Komajda, Michel; Steg, Philippe Gabriel; Tavazzi, Luigi; Tendera, Michal; Swedberg, Karl

    2015-10-01

    Elevated resting heart rate is associated with increased cardiovascular risk, particularly in patients with left ventricular systolic dysfunction. Heart rate is not monitored routinely in these patients. We hypothesized that routine monitoring of heart rate would increase its prognostic value in patients with left ventricular systolic dysfunction. We analyzed the relationship between heart rate measurements and a range of adverse cardiovascular outcomes, including hospitalization for worsening heart failure, in the pooled placebo-treated patients from the morBidity-mortality EvAlUaTion of the If inhibitor ivabradine in patients with coronary disease and left ventricULar dysfunction (BEAUTIFUL) trial and Systolic Heart failure treatment with the If inhibitor ivabradine (SHIFT) Trial, using standard and time-varying covariate Cox proportional hazards models. By adjusting for other prognostic factors, models were fitted for baseline heart rate alone or for time-updated heart rate (latest heart rate) alone or corrected for baseline heart rate or for immediate previous time-updated heart rate. Baseline heart rate was strongly associated with all outcomes apart from hospitalization for myocardial infarction. Time-updated heart rate increased the strengths of associations for all outcomes. Adjustment for baseline heart rate or immediate previous time-updated heart rate modestly reduced the prognostic importance of time-updated heart rate. For hospitalization for worsening heart failure, each 5 beats/min increase in baseline heart rate and time-updated heart rate was associated with a 15% (95% confidence interval, 12-18) and 22% (confidence interval, 19-40) increase in risk, respectively. Even after correction, the prognostic value of time-updated heart rate remained greater. In patients with left ventricular systolic dysfunction, time-updated heart rate is more strongly related with adverse cardiovascular outcomes than baseline heart rate. Heart rate should be measured to

  6. An artificial pancreas provided a novel model of blood glucose level variability in beagles.

    Science.gov (United States)

    Munekage, Masaya; Yatabe, Tomoaki; Kitagawa, Hiroyuki; Takezaki, Yuka; Tamura, Takahiko; Namikawa, Tsutomu; Hanazaki, Kazuhiro

    2015-12-01

    Although the effects on prognosis of blood glucose level variability have gained increasing attention, it is unclear whether blood glucose level variability itself or the manifestation of pathological conditions that worsen prognosis. Then, previous reports have not been published on variability models of perioperative blood glucose levels. The aim of this study is to establish a novel variability model of blood glucose concentration using an artificial pancreas. We maintained six healthy, male beagles. After anesthesia induction, a 20-G venous catheter was inserted in the right femoral vein and an artificial pancreas (STG-22, Nikkiso Co. Ltd., Tokyo, Japan) was connected for continuous blood glucose monitoring and glucose management. After achieving muscle relaxation, total pancreatectomy was performed. After 1 h of stabilization, automatic blood glucose control was initiated using the artificial pancreas. Blood glucose level varied for 8 h, alternating between the target blood glucose values of 170 and 70 mg/dL. Eight hours later, the experiment was concluded. Total pancreatectomy was performed for 62 ± 13 min. Blood glucose swings were achieved 9.8 ± 2.3 times. The average blood glucose level was 128.1 ± 5.1 mg/dL with an SD of 44.6 ± 3.9 mg/dL. The potassium levels after stabilization and at the end of the experiment were 3.5 ± 0.3 and 3.1 ± 0.5 mmol/L, respectively. In conclusion, the results of the present study demonstrated that an artificial pancreas contributed to the establishment of a novel variability model of blood glucose levels in beagles.

  7. Immortalized endothelial cell lines for in vitro blood-brain barrier models: A systematic review.

    Science.gov (United States)

    Rahman, Nurul Adhwa; Rasil, Alifah Nur'ain Haji Mat; Meyding-Lamade, Uta; Craemer, Eva Maria; Diah, Suwarni; Tuah, Ani Afiqah; Muharram, Siti Hanna

    2016-07-01

    Endothelial cells play the most important role in construction of the blood-brain barrier. Many studies have opted to use commercially available, easily transfected or immortalized endothelial cell lines as in vitro blood-brain barrier models. Numerous endothelial cell lines are available, but we do not currently have strong evidence for which cell lines are optimal for establishment of such models. This review aimed to investigate the application of immortalized endothelial cell lines as in vitro blood-brain barrier models. The databases used for this review were PubMed, OVID MEDLINE, ProQuest, ScienceDirect, and SpringerLink. A narrative systematic review was conducted and identified 155 studies. As a result, 36 immortalized endothelial cell lines of human, mouse, rat, porcine and bovine origins were found for the establishment of in vitro blood-brain barrier and brain endothelium models. This review provides a summary of immortalized endothelial cell lines as a guideline for future studies and improvements in the establishment of in vitro blood-brain barrier models. It is important to establish a good and reproducible model that has the potential for multiple applications, in particular a model of such a complex compartment such as the blood-brain barrier.

  8. Mathematical modelling of cerebral blood circulation and cerebral autoregulation: towards preventing intracranial hemorrhages in preterm newborns.

    Science.gov (United States)

    Lampe, Renée; Botkin, Nikolai; Turova, Varvara; Blumenstein, Tobias; Alves-Pinto, Ana

    2014-01-01

    Impaired cerebral autoregulation leads to fluctuations in cerebral blood flow, which can be especially dangerous for immature brain of preterm newborns. In this paper, two mathematical models of cerebral autoregulation are discussed. The first one is an enhancement of a vascular model proposed by Piechnik et al. We extend this model by adding a polynomial dependence of the vascular radius on the arterial blood pressure and adjusting the polynomial coefficients to experimental data to gain the autoregulation behavior. Moreover, the inclusion of a Preisach hysteresis operator, simulating a hysteretic dependence of the cerebral blood flow on the arterial pressure, is tested. The second model couples the blood vessel system model by Piechnik et al. with an ordinary differential equation model of cerebral autoregulation by Ursino and Lodi. An optimal control setting is proposed for a simplified variant of this coupled model. The objective of the control is the maintenance of the autoregulatory function for a wider range of the arterial pressure. The control can be interpreted as the effect of a medicament changing the cerebral blood flow by, for example, dilation of blood vessels. Advanced numerical methods developed by the authors are applied for the numerical treatment of the control problem.

  9. Mathematical Modelling of Cerebral Blood Circulation and Cerebral Autoregulation: Towards Preventing Intracranial Hemorrhages in Preterm Newborns

    Directory of Open Access Journals (Sweden)

    Renée Lampe

    2014-01-01

    Full Text Available Impaired cerebral autoregulation leads to fluctuations in cerebral blood flow, which can be especially dangerous for immature brain of preterm newborns. In this paper, two mathematical models of cerebral autoregulation are discussed. The first one is an enhancement of a vascular model proposed by Piechnik et al. We extend this model by adding a polynomial dependence of the vascular radius on the arterial blood pressure and adjusting the polynomial coefficients to experimental data to gain the autoregulation behavior. Moreover, the inclusion of a Preisach hysteresis operator, simulating a hysteretic dependence of the cerebral blood flow on the arterial pressure, is tested. The second model couples the blood vessel system model by Piechnik et al. with an ordinary differential equation model of cerebral autoregulation by Ursino and Lodi. An optimal control setting is proposed for a simplified variant of this coupled model. The objective of the control is the maintenance of the autoregulatory function for a wider range of the arterial pressure. The control can be interpreted as the effect of a medicament changing the cerebral blood flow by, for example, dilation of blood vessels. Advanced numerical methods developed by the authors are applied for the numerical treatment of the control problem.

  10. Modeling Cerebral Blood Flow Control During Posture Change from Sitting to Standing

    DEFF Research Database (Denmark)

    Olufsen, Mette; Tran, Hien; Ottesen, Johnny T.

    2004-01-01

    , the heart, and venous valves. We use physiologically based control mechanisms to describe the regulation of cerebral blood velocity and arterial pressure in response to orthostatic hypotension resulting from postural change. Beyond active control mechanisms we also have to include certain passive non......Hypertension, decreased cerebral blood flow, and diminished cerebral blood flow regulation, are among the first signs indicating the presence of cerebral vascular disease. In this paper, we will present a mathematical model that can predict blood flow and pressure during posture change from sitting......-linearities in some of the compliance-pressure and resistance-pressure relationships. Futhermore, an acurate and physiologically based submodel, describing the dynamics of how gravity effects the blood distribution during suspine changes, is included. To justify the fidelity of our mathematical model and control...

  11. A behavior model for blood donors and marketing strategies to retain and attract them

    Directory of Open Access Journals (Sweden)

    Covadonga Aldamiz-echevarria

    2014-06-01

    Full Text Available OBJECTIVE: analyze and propose a theoretical model that describes blood donor decisions to help staff working in blood banks (nurses and others in their efforts to capture and retain donors.METHODS: analysis of several studies on the motivations to give blood in Spain over the last six years, as well as past literature on the topic, the authors' experiences in the last 25 years in over 15 Non Governmental Organizations with different levels of responsibilities, their experiences as blood donors and the informal interviews developed during those 25 years.RESULTS: a model is proposed with different internal and external factors that influence blood donation, as well as the different stages of the decision-making process.CONCLUSION: the knowledge of the donation process permits the development of marketing strategies that help to increase donors and donations.

  12. The application of extended modified Lambert Beer model for measurement of blood carboxyhemoglobin and oxyhemoglobin saturation

    National Research Council Canada - National Science Library

    Huong, Audrey; Ngu, Xavier

    2014-01-01

    This work presents the use of extended Modified Lambert Beer (MLB) model for accurate and continuous monitoring of percent blood carboxyhemoglobin (COHb) (SCO) and oxyhemoglobin (OxyHb) saturation (SO2...

  13. Clinical usefulness of carotid arterial wave intensity in assessing left ventricular systolic and early diastolic performance.

    Science.gov (United States)

    Ohte, Nobuyuki; Narita, Hitomi; Sugawara, Motoaki; Niki, Kiyomi; Okada, Takashi; Harada, Akimitsu; Hayano, Junichiro; Kimura, Genjiro

    2003-07-01

    Wave intensity (WI) is a novel hemodynamic index, which is defined as (d P/d t) x (d U/d t) at any site of the circulation, where d P/d t and d U/d t are the derivatives of blood pressure and velocity with respect to time, respectively. However, the pathophysiological meanings of this index have not been fully elucidated in the clinical setting. Accordingly, we investigated this issue in 64 patients who underwent invasive evaluation of left ventricular (LV) function. WI was obtained at the right carotid artery using a color Doppler system for blood velocity measurement combined with an echo-tracking method for detecting vessel diameter changes. The vessel diameter changes were automatically converted to pressure waveforms by calibrating its peak and minimum values by systolic and diastolic brachial blood pressures. The WI of the patients showed two sharp positive peaks. The first peak was found at the very early phase of LV ejection, while the second peak was observed near end-ejection. The magnitude of the first peak of WI significantly correlated with the maximum rate of LV pressure rise (LV max. d P/d t) (r = 0.74, P WI significantly correlated with the time constant of LV relaxation (r = -0.77, P WI reflects LV contractile performance, and the amplitude of the second peak of WI is determined by LV behavior during the period from late systole to isovolumic relaxation. WI is a noninvasively obtained, clinically useful parameter for the evaluation of LV systolic and early diastolic performance at the same time.

  14. Multiscale Modeling of Blood Flow: Coupling Finite Elements with Smoothed Dissipative Particle Dynamics

    KAUST Repository

    Moreno Chaparro, Nicolas

    2013-06-01

    A variational multi scale approach to model blood flow through arteries is proposed. A finite element discretization to represent the coarse scales (macro size), is coupled to smoothed dissipative particle dynamics that captures the fine scale features (micro scale). Blood is assumed to be incompressible, and flow is described through the Navier Stokes equation. The proposed cou- pling is tested with two benchmark problems, in fully coupled systems. Further refinements of the model can be incorporated in order to explicitly include blood constituents and non-Newtonian behavior. The suggested algorithm can be used with any particle-based method able to solve the Navier-Stokes equation.

  15. Nicholas Metropolis Award Talk for Outstanding Doctoral Thesis Work in Computational Physics: Computational biophysics and multiscale modeling of blood cells and blood flow in health and disease

    Science.gov (United States)

    Fedosov, Dmitry

    2011-03-01

    Computational biophysics is a large and rapidly growing area of computational physics. In this talk, we will focus on a number of biophysical problems related to blood cells and blood flow in health and disease. Blood flow plays a fundamental role in a wide range of physiological processes and pathologies in the organism. To understand and, if necessary, manipulate the course of these processes it is essential to investigate blood flow under realistic conditions including deformability of blood cells, their interactions, and behavior in the complex microvascular network. Using a multiscale cell model we are able to accurately capture red blood cell mechanics, rheology, and dynamics in agreement with a number of single cell experiments. Further, this validated model yields accurate predictions of the blood rheological properties, cell migration, cell-free layer, and hemodynamic resistance in microvessels. In addition, we investigate blood related changes in malaria, which include a considerable stiffening of red blood cells and their cytoadherence to endothelium. For these biophysical problems computational modeling is able to provide new physical insights and capabilities for quantitative predictions of blood flow in health and disease.

  16. Effects of far infrared rays irradiated from ceramic material (BIOCERAMIC) on psychological stress-conditioned elevated heart rate, blood pressure, and oxidative stress-suppressed cardiac contractility.

    Science.gov (United States)

    Leung, Ting-Kai; Chen, Chien-Ho; Tsai, Shih-Ying; Hsiao, George; Lee, Chi-Ming

    2012-10-31

    The present study examined the effects of BIOCERAMIC on psychological stress-conditioned elevated heart rate, blood pressure and oxidative stress-suppressed cardiac contractility using in vivo and in vitro animal models. We investigated the effects of BIOCERAMIC on the in vivo cardiovascular hemodynamic parameters of rats by monitoring their heart rates, systolic blood pressure, mean blood pressure and diastolic blood pressure. Thereafter, we assayed its effects on the heart rate in an isolated frog heart with and without adrenaline stimulation, and on cardiac contractility under oxidative stress. BIOCERAMIC caused significant decreases in heart rates and systolic and mean blood pressure in the stress-conditioned heart rate rat models (P heart with and without adrenaline stimulation (P < 0.05), and normalized cardiac contractility under oxidative stress (P < 0.05). BIOCERAMIC may, therefore, normalize the effects of psychological stress and oxidative stress conditions.

  17. Crossover comparison of atenolol, enalapril, hydrochlorothiazide and isradipine for isolated systolic systemic hypertension.

    Science.gov (United States)

    Silagy, C A; McNeil, J J; McGrath, B P

    1992-11-15

    The benefit of antihypertensive therapy in reducing cardiovascular morbidity and mortality associated with isolated systolic hypertension has now been established by the Systolic Hypertension in the Elderly Program. However, there is little information about the relative effectiveness of different drug regimens in this condition. This study compared the efficacy and tolerability of 50 mg of atenolol, 10 mg of enalapril, 25 mg of hydrochlorothiazide and 2.5 mg of isradipine in the treatment of isolated systolic hypertension. After a 3-week placebo run-in phase, 24 subjects were randomized into a 4-period double-blind crossover study by use of an orthogonal latin square design. Treatment periods were of 6 weeks' duration with titration to a higher dose after 4 weeks in those not reaching goal blood pressure (BP). Each active treatment was followed by a 3-week placebo washout. Casual clinic and 24-hour ambulatory BP (Accutracker II) were measured at the end of each treatment phase. Routine biochemistry was also performed after the placebo run-in, at the end of each active treatment phase, and after the placebo run-out. Of the 24 subjects entered (mean age 72.3 years, 38% men) 20 completed the whole study. Mean +/- standard deviation of supine clinic and daytime ambulatory BP on entry were 181/79 +/- 21/9 mm Hg and 165/82 +/- 23/15 mm Hg, respectively. All drugs reduced mean casual and ambulatory BP significantly relative to placebo but only hydrochlorothiazide and enalapril produced a consistent hypotensive effect throughout the entire 24-hour period. Isradipine and enalapril exhibited a relatively greater effect on reducing systolic BP than either hydrochlorothiazide or atenolol.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Effects of Sacubitril/Valsartan Versus Olmesartan on Central Hemodynamics in the Elderly With Systolic Hypertension: The PARAMETER Study.

    Science.gov (United States)

    Williams, Bryan; Cockcroft, John R; Kario, Kazuomi; Zappe, Dion H; Brunel, Patrick C; Wang, Qian; Guo, Weinong

    2017-03-01

    Effective treatment of systolic hypertension in elderly patients remains a major therapeutic challenge. A multicenter, double-blind, randomized controlled trial with sacubitril/valsartan (LCZ696), a first-in-class angiotensin receptor neprilysin inhibitor, was conducted to determine its effects versus olmesartan (angiotensin receptor blocker) on central aortic pressures, in elderly patients (aged ≥60 years) with systolic hypertension and pulse pressure >60 mm Hg, indicative of arterial stiffness. Patients (n=454; mean age, 67.7 years; mean seated systolic blood pressure, 158.6 mm Hg; mean seated pulse pressure, 69.7 mm Hg) were randomized to receive once-daily sacubitril/valsartan 200 mg or olmesartan 20 mg, force titrated to double the initial doses after 4 weeks, before primary assessment at 12 weeks. The study extended double-blind treatment for 12 to 52 weeks, during which amlodipine (2.5-5 mg) and subsequently hydrochlorothiazide (6.25-25 mg) were added-on for patients not achieving blood pressure target (olmesartan by -3.7 mm Hg (P=0.010), further corroborated by secondary assessments at week 12 (central aortic pulse pressure, -2.4 mm Hg, Polmesartan (47%) versus sacubitril/valsartan (32%; Polmesartan in reducing clinic and ambulatory central aortic and brachial pressures in elderly patients with systolic hypertension and stiff arteries. © 2017 American Heart Association, Inc.

  19. Design guidelines for an umbilical cord blood stem cell therapy quality assessment model

    Science.gov (United States)

    Januszewski, Witold S.; Michałek, Krzysztof; Yagensky, Oleksandr; Wardzińska, Marta

    The paper enlists the pivotal guidelines for producing an empirical umbilical cord blood stem cell therapy quality assessment model. The methodology adapted was single equation linear model with domain knowledge derived from MEDAFAR classification. The resulting model is ready for therapeutical application.

  20. Visit-to-Visit Variability in Blood Pressure and Kidney and Cardiovascular Outcomes in Patients With Type 2 Diabetes and Nephropathy : A Post Hoc Analysis From the RENAAL Study and the Irbesartan Diabetic Nephropathy Trial

    NARCIS (Netherlands)

    McMullan, Ciaran J.; Lambers Heerspink, Hiddo J.; Parving, Hans-Henrik; Dwyer, Jamie P.; Forman, John P.; de Zeeuw, Dick

    2014-01-01

    Background: Increased systolic blood pressure variability between outpatient visits is associated with increased incidence of cardiovascular end points. However, few studies have examined the association of visit-to-visit variability in systolic blood pressure with clinically relevant kidney disease

  1. Impact of home blood pressure telemonitoring and blood pressure control: a meta-analysis of randomized controlled studies.

    Science.gov (United States)

    Omboni, Stefano; Guarda, Alessia

    2011-09-01

    Home blood pressure telemonitoring figures among the possible solutions that could help improve blood pressure control of hypertensive patients. To summarize the effectiveness of home blood pressure telemonitoring on blood pressure control from randomized, controlled studies. Electronic databases were searched for publications in English, reporting on randomized trials of home blood pressure telemonitoring vs. usual care. Outcome measures were office or ambulatory blood pressure changes, rate of blood pressure control, and number of antihypertensive drugs used by patients. A random effects model was applied. Twelve studies met inclusion criteria. A high level of heterogeneity was found among studies for all the variables explored. Office blood pressure was reduced significantly more in patients randomized to home telemonitoring (systolic: 5.64 (95% confidence interval: 7.92, 3.36) mm Hg; diastolic: 2.78 (3.93, 1.62) mm Hg; 11 comparisons, n = 4,389). The effect on ambulatory blood pressure was smaller than on office blood pressure (systolic: 2.28 (4.32, 0.24); diastolic: 1.38 (3.55, +0.79) mm Hg; 3 comparisons, n = 655). The relative risk of blood pressure normalization (telemonitoring vs. the usual care group was 1.31 (1.06, 1.62) (5 comparisons, n = 2,432 subjects). Use of telemonitoring was associated with a significantly increased use of antihypertensive medications (+0.22 (+0.02, +0.43), 5 comparisons, n = 1,991). Home blood pressure telemonitoring may represent a useful tool to improve blood pressure control. However, heterogeneity of published studies suggests that well designed, large-scale, randomized, controlled studies are still needed to demonstrate the clinical usefulness of this technique.

  2. Modeling Superparamagnetic Particles in Blood Flow for Applications in Magnetic Drug Targeting

    Directory of Open Access Journals (Sweden)

    Iris Rukshin

    2017-06-01

    Full Text Available Magnetic drug targeting is a technique that involves the binding of medicine to magnetizable particles to allow for more specific transport to the target location. This has recently come to light as a method of drug delivery that reduces the disadvantages of conventional, systemic treatments. This study developed a mathematical model for tracking individual superparamagnetic nanoparticles in blood flow in the presence of an externally applied magnetic field. The model considers the magnetic attraction between the particles and the external magnet, influence of power law flow, diffusive interaction between the particles and blood, and random collisions with red blood cells. A stochastic system of differential equations is presented and solved numerically to simulate the paths taken by particles in a blood vessel. This study specifically focused on localized cancer treatment, in which a surface tumor is accessed through smaller blood vessels, which are more conducive to this delivery method due to slower flow velocities and smaller diameters. The probability of the particles reaching the tumor location is found to be directly dependent on ambient factors; thus, diffusion through Brownian motion and red blood cell collisions, different magnetic field and force models, blood viscosities, and release points are considered.

  3. EFFECT OF LEFT VENTRICULAR SYSTOLIC DYSFUNCTION ON CEREBRAL HEMODYNAMICS IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION (THE RESULTS OF OBSERVATIONAL STUDIES

    Directory of Open Access Journals (Sweden)

    V. E. Kulikov

    2015-12-01

    Full Text Available Aim. To study the effect of left ventricular (LV systolic dysfunction on cerebral hemodynamic in patients with ST segment elevation myocardial infarction (STEMI during acute period. Material and methods. Cerebral hemodynamics ultrasound assessment was performed in the extra-and intracranial vessels in 118 patients with STEMI. Results. Significant changes in cerebral hemodynamics were found in LV systolic dysfunction with ejection fraction (LVEF ≤40% due to hemispheric blood flow asymmetry in the middle cerebral artery (MCA as large as 45.1±6.7% with correlation coefficient r=-0.87. Compensation of cerebral blood flow was manifested in vasoconstriction or vasodilation (resistive index 0.63-0.76 and 0.49-0.43 c.u., respectively. Conclusion. A strong relationship between LV systolic dysfunction and cerebral hemodynamic was found in patients with STEMI. It was manifested in significant contralateral hemispheric blood flow asymmetry in MCA in patients with LVEF ≤40%. Reduction in cerebral blood flow velocity activated autoregulation mechanism in the form of vasoconstriction or vasodilation.

  4. [A five-element lumped-parameter model for cerebral blood flow autoregulation].

    Science.gov (United States)

    Wang, Shengzhang; Yao, Wei; Ding, Guanghong

    2009-10-01

    Utilizing the third-order polynomial curve fitted to the experimental data, which represents the relationship between cerebral blood flow (CBF) and mean artery blood pressure (MABP), we constructed a lumped-parameter dynamic model with 5 elements. In this model; the resistance is not constants it is determined by the fitted curve. We simulated the process of CBF autoregulation numerically by solving the govern equation of this model and got quite accurate results. Furthermore, we studied the influence of hemodynamic parameters on the CBF autoregulation by this model and proved that the characteristic resistance is the most important factor.

  5. Left ventricular diastolic dysfunction limits use of maximum systolic elastance as an index of contractile function.

    Science.gov (United States)

    Zile, M R; Izzi, G; Gaasch, W H

    1991-02-01

    We tested the hypothesis that maximum systolic elastance (Emax) fails to detect a decline in left ventricular (LV) contractile function when diastolic dysfunction is present. Canine hearts were studied in an isolated blood-perfused heart apparatus (isovolumic LV); contractile dysfunction was produced by 60 or 90 minutes of global ischemia, followed by 90 minutes of reperfusion. Nine normal hearts underwent 60 minutes of ischemia, and five underwent 90 minutes of ischemia. After the ischemia-reperfusion sequence, developed pressure, pressure-volume area, and myocardial ATP level were significantly less than those at baseline in all 14 hearts. In the group undergoing 60 minutes of ischemia, LV diastolic pressure did not increase, whereas Emax decreased from 5.2 +/- 2.5 to 2.9 +/- 1.4 mm Hg/ml (p less than 0.05). In the group undergoing 90 minutes of ischemia, diastolic pressure increased (from 10 +/- 2 to 37 +/- 20 mm Hg, p less than 0.05), and Emax did not change significantly (from 5.1 +/- 4.3 to 4.3 +/- 2.5 mm Hg/ml). A second series of experiments was performed in 13 hearts with pressure-overload hypertrophy (aortic-band model with echocardiography and catheterization studies before the ischemia-reperfusion protocol). Five had evidence for pump failure, whereas eight remained compensated. After 60 minutes of ischemia and 90 minutes of reperfusion, developed pressure, pressure-volume area, and myocardial ATP level were significantly less than those at baseline in all 13 hearts. In the group with compensated LV hypertrophy, LV diastolic pressure did not change, whereas Emax decreased from 6.9 +/- 3.0 to 3.1 +/- 2.3 mm Hg/ml (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Cardiac contractility, central haemodynamics and blood pressure regulation during semistarvation

    DEFF Research Database (Denmark)

    Stokholm, K H; Breum, L; Astrup, A

    1991-01-01

    , the peak ejection rate and changes in end-systolic volume. Also the diastolic function evaluated by the peak filling rate remained normal. Furthermore, no sign of backward failure could be demonstrated since the central blood volume was not significantly increased. Both systolic and diastolic blood...

  7. Biological correlates of blood pressure variability in elderly at high risk of cardiovascular disease.

    Science.gov (United States)

    Poortvliet, Rosalinde K E; Lloyd, Suzanne M; Ford, Ian; Sattar, Naveed; de Craen, Anton J M; Wijsman, Liselotte W; Mooijaart, Simon P; Westendorp, Rudi G J; Jukema, J Wouter; de Ruijter, Wouter; Gussekloo, Jacobijn; Stott, David J

    2015-04-01

    Visit-to-visit variability in blood pressure is an independent predictor of cardiovascular disease. This study investigates biological correlates of intra-individual variability in blood pressure in older persons. Nested observational study within the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) among 3,794 male and female participants (range 70-82 years) with a history of, or risk factors for cardiovascular disease. Individual visit-to-visit variability in systolic and diastolic blood pressure and pulse pressure (expressed as 1 SD in mm Hg) was assessed using nine measurements over 2 years. Correlates of higher visit-to-visit variability were examined at baseline, including markers of inflammation, endothelial function, renal function and glucose homeostasis. Over the first 2 years, the mean intra-individual variability (1 SD) was 14.4mm Hg for systolic blood pressure, 7.7mm Hg for diastolic blood pressure, and 12.6mm Hg for pulse pressure. After multivariate adjustment a higher level of interleukin-6 at baseline was consistently associated with higher intra-individual variability of blood pressure, including systolic, diastolic, and pulse pressure. Markers of endothelial function (Von Willebrand factor, tissue plasminogen activator), renal function (glomerular filtration rate) and glucose homeostasis (blood glucose, homeostatic model assessment index) were not or to a minor extent associated with blood pressure variability. In an elderly population at risk of cardiovascular disease, inflammation (as evidenced by higher levels of interleukin-6) is associated with higher intra-individual variability in systolic, diastolic, and pulse pressure. © American Journal of Hypertension, Ltd 2014. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. High blood pressure and cerebral white matter lesion progression in the general population.

    Science.gov (United States)

    Verhaaren, Benjamin F J; Vernooij, Meike W; de Boer, Renske; Hofman, Albert; Niessen, Wiro J; van der Lugt, Aad; Ikram, M Arfan

    2013-06-01

    High blood pressure is considered an important risk factor for cerebral white matter lesions (WMLs) in the aging population. In a longitudinal population-based study of 665 nondemented persons, we investigated the longitudinal relationship of systolic blood pressure, diastolic blood pressure, and pulse pressure with annual progression of WMLs. Means of blood pressure were calculated over a 5-year period before longitudinal MRI scanning. WML progression was subsequently measured on 2 scans 3.5 years apart. We performed analyses with linear regression models and evaluated adjustments for age, sex, cardiovascular risk factors, and baseline WML volume. In addition, we evaluated whether treatment of hypertension is related to less WML progression. Both systolic and diastolic blood pressures were significantly associated with annual WML progression (regression coefficient [95% confidence interval], 0.08 [0.03; 0.14] mL/y and 0.09 [0.03; 0.15] mL/y per SD increase in systolic and diastolic blood pressure, respectively). Pulse pressure was also significantly associated with WML progression, but not independent from hypertension. After adjustment for baseline WML volume, only systolic blood pressure remained significantly associated: 0.05 (0.00; 0.09) mL/y per SD increase. People with uncontrolled untreated hypertension had significantly more WML progression than people with uncontrolled treated hypertension (difference [95% confidence interval], 0.12 [0.00; 0.23] mL/y). The present study further establishes high blood pressure to precede WMLs and implies that hypertension treatment could reduce WML progression in the general population.

  9. Improving the clinical management of traumatic brain injury through the pharmacokinetic modeling of peripheral blood biomarkers.

    Science.gov (United States)

    Dadas, Aaron; Washington, Jolewis; Marchi, Nicola; Janigro, Damir

    2016-11-30

    Blood biomarkers of neurovascular damage are used clinically to diagnose the presence severity or absence of neurological diseases, but data interpretation is confounded by a limited understanding of their dependence on variables other than the disease condition itself. These include half-life in blood, molecular weight, and marker-specific biophysical properties, as well as the effects of glomerular filtration, age, gender, and ethnicity. To study these factors, and to provide a method for markers' analyses, we developed a kinetic model that allows the integrated interpretation of these properties. The pharmacokinetic behaviors of S100B (monomer and homodimer), Glial Fibrillary Acidic Protein and Ubiquitin C-Terminal Hydrolase L1 were modeled using relevant chemical and physical properties; modeling results were validated by comparison with data obtained from healthy subjects or individuals affected by neurological diseases. Brain imaging data were used to model passage of biomarkers across the blood-brain barrier. Our results show the following: (1) changes in biomarker serum levels due to age or disease progression are accounted for by differences in kidney filtration; (2) a significant change in the brain-to-blood volumetric ratio, which is characteristic of infant and adult development, contributes to variation in blood concentration of biomarkers; (3) the effects of extracranial contribution at steady-state are predicted in our model to be less important than suspected, while the contribution of blood-brain barrier disruption is confirmed as a significant factor in controlling markers' appearance in blood, where the biomarkers are typically detected; (4) the contribution of skin to the marker S100B blood levels depends on a direct correlation with pigmentation and not ethnicity; the contribution of extracranial sources for other markers requires further investigation. We developed a multi-compartment, pharmacokinetic model that integrates the biophysical

  10. A theoretical computerized study for the electrical conductivity of arterial pulsatile blood flow by an elastic tube model.

    Science.gov (United States)

    Shen, Hua; Zhu, Yong; Qin, Kai-Rong

    2016-12-01

    The electrical conductivity of pulsatile blood flow in arteries is an important factor for the application of the electrical impedance measurement system in clinical settings. The electrical conductivity of pulsatile blood flow depends not only on blood-flow-induced red blood cell (RBC) orientation and deformation but also on artery wall motion. Numerous studies have investigated the conductivity of pulsatile blood based on a rigid tube model, in which the effects of wall motion on blood conductivity are not considered. In this study, integrating Ling and Atabek's local flow theory and Maxwell-Fricke theory, we develop an elastic tube model to explore the effects of wall motion as well as blood flow velocity on blood conductivity. The simulation results suggest that wall motion, rather than blood flow velocity, is the primary factor that affects the conductivity of flowing blood in arteries.

  11. Systolic multipliers for finite fields GF(2 exp m)

    Science.gov (United States)

    Yeh, C.-S.; Reed, I. S.; Truong, T. K.

    1984-01-01

    Two systolic architectures are developed for performing the product-sum computation AB + C in the finite field GF(2 exp m) of 2 exp m elements, where A, B, and C are arbitrary elements of GF(2 exp m). The first multiplier is a serial-in, serial-out one-dimensional systolic array, while the second multiplier is a parallel-in, parallel-out two-dimensional systolic array. The first multiplier requires a smaller number of basic cells than the second multiplier. The second multiplier needs less average time per computation than the first multiplier, if a number of computations are performed consecutively. To perform single computations both multipliers require the same computational time. In both cases the architectures are simple and regular and possess the properties of concurrency and modularity. As a consequence, they are well suited for use in VLSI systems.

  12. One dimensional and multiscale models for blood flow circulation

    OpenAIRE

    Lamponi, Daniele

    2004-01-01

    The aim of this work is to provide mathematically sound and computationally effective tools for the numerical simulation of the interaction between fluid and structures as occurring, for instance, in the simulation of the human cardiovascular system. This problem is global, in the sense that local changes can modify the solution far away. From the point of view of computing and modelling this calls for the use of multiscale methods, where simplified models are used to treat the global problem...

  13. A model for oxygen-dependent backscattering spectroscopic contrast from single red blood cells (Conference Presentation)

    Science.gov (United States)

    Liu, Rongrong; Yi, Ji; Chen, Siyu; Zhang, Hao F.; Backman, Vadim

    2016-03-01

    The oxygen-dependent absorption of hemoglobin provides the fundamental contrast for all label-free techniques measuring blood oxygenation. When hemoglobin is packaged into red blood cells (RBCs), the structure of the cells creates light scattering which also depends on the absorption based on the Kramers-Kronig relationship. Thus a proper characterization of the optical behaviors of blood has been a key to any accurate measurement of blood oxygenation, particularly at the capillary level where RBCs are dispersed individually in contrast to a densely packed whole blood. Here we provided a theoretical model under Born Approximation to characterize the oxygen dependent backscattering spectroscopic contrast from single RBCs. Using this theoretical model, we conducted simulations on both oxygenated and deoxygenated single RBCs with different sizes for standard and possible deformed cell geometries in blood flow, all which suggested similar backscattering spectroscopic contrast and were confirmed by Mie Theory and experiments using visible Optical Coherence Tomography (visOCT). As long as the cell size satisfies Gaussian distribution with a coefficient variance (C.V.) large enough, there is clear absorption contrast between the backscattering spectra of oxygenated and deoxygenated single RBCs calculated by this model, so oxygen saturation can then be characterized. Thus, this theoretical model can be extended to extract absorption features of other scattering particles as long as they satisfy Born Approximation.

  14. A Mixed Approach for Modeling Blood Flow in Brain Microcirculation

    Science.gov (United States)

    Peyrounette, M.; Sylvie, L.; Davit, Y.; Quintard, M.

    2014-12-01

    We have previously demonstrated [1] that the vascular system of the healthy human brain cortex is a superposition of two structural components, each corresponding to a different spatial scale. At small-scale, the vascular network has a capillary structure, which is homogeneous and space-filling over a cut-off length. At larger scale, veins and arteries conform to a quasi-fractal branched structure. This structural duality is consistent with the functional duality of the vasculature, i.e. distribution and exchange. From a modeling perspective, this can be viewed as the superposition of: (a) a continuum model describing slow transport in the small-scale capillary network, characterized by a representative elementary volume and effective properties; and (b) a discrete network approach [2] describing fast transport in the arterial and venous network, which cannot be homogenized because of its fractal nature. This problematic is analogous to modeling problems encountered in geological media, e.g, in petroleum engineering, where fast conducting channels (wells or fractures) are embedded in a porous medium (reservoir rock). An efficient method to reduce the computational cost of fractures/continuum simulations is to use relatively large grid blocks for the continuum model. However, this also makes it difficult to accurately couple both structural components. In this work, we solve this issue by adapting the "well model" concept used in petroleum engineering [3] to brain specific 3-D situations. We obtain a unique linear system of equations describing the discrete network, the continuum and the well model coupling. Results are presented for realistic geometries and compared with a non-homogenized small-scale network model of an idealized periodic capillary network of known permeability. [1] Lorthois & Cassot, J. Theor. Biol. 262, 614-633, 2010. [2] Lorthois et al., Neuroimage 54 : 1031-1042, 2011. [3] Peaceman, SPE J. 18, 183-194, 1978.

  15. Low Power Systolic Array Based Digital Filter for DSP Applications

    Directory of Open Access Journals (Sweden)

    S. Karthick

    2015-01-01

    Full Text Available Main concepts in DSP include filtering, averaging, modulating, and correlating the signals in digital form to estimate characteristic parameter of a signal into a desirable form. This paper presents a brief concept of low power datapath impact for Digital Signal Processing (DSP based biomedical application. Systolic array based digital filter used in signal processing of electrocardiogram analysis is presented with datapath architectural innovations in low power consumption perspective. Implementation was done with ASIC design methodology using TSMC 65 nm technological library node. The proposed systolic array filter has reduced leakage power up to 8.5% than the existing filter architectures.

  16. Low Power Systolic Array Based Digital Filter for DSP Applications.

    Science.gov (United States)

    Karthick, S; Valarmathy, S; Prabhu, E

    2015-01-01

    Main concepts in DSP include filtering, averaging, modulating, and correlating the signals in digital form to estimate characteristic parameter of a signal into a desirable form. This paper presents a brief concept of low power datapath impact for Digital Signal Processing (DSP) based biomedical application. Systolic array based digital filter used in signal processing of electrocardiogram analysis is presented with datapath architectural innovations in low power consumption perspective. Implementation was done with ASIC design methodology using TSMC 65 nm technological library node. The proposed systolic array filter has reduced leakage power up to 8.5% than the existing filter architectures.

  17. Anti—inflammatory effect of cerivastatin in vascular injury independent of serum cholesterol and blood pressure lowering effects in mouse model

    Institute of Scientific and Technical Information of China (English)

    陈小东; 李震; 等

    2002-01-01

    Objective:To observe the anti-inflammatory effect of cerivastatin in a mouse model of vascular injury and its cholesterol-lowering effect.Methods:We developed a mouse model of vascular remodeling induced by polyethylene cuff placement and determined the anti-inflannatory effects of cerivastatin in wild mice.Cerivastatin was given by Alzet micro-osmotic minipumps implanted intraperitoneally at the same time as cuff placement at doses of 0.1mg/kg,0.5mg/kgand1mg/kgper day,respectively for 2weeks after cuff placement.The insufficient doses of Cerivastatin to lower serum cholesterol and systolic blood pressue through the neointimal formation and BrdUindex were investigated in mouse formation and BrdUindex were investigated in the 1mg/kg cerivastatin,but not in the 0.1mg/kgand0.5mg/kg cerivastatin,Furthermore,1mg/kg of cerivastatin significantly inhibited the expression of tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)without lowering serum cholesterol.Conclusions:These results suggest that cerivastatin can inhitit vascular inflammation and ahe proliferation of vascular smooth muscle cells(VSMCs)through its lipid-lowering independent action.Such effects of cerivastatin may be an important mechanism,by which it prevents the development of atherosclerotic lesions.

  18. Multiscale modeling of sickle anemia blood blow by Dissipative Partice Dynamics

    Science.gov (United States)

    Lei, Huan; Caswell, Bruce; Karniadakis, George

    2011-11-01

    A multi-scale model for sickle red blood cell is developed based on Dissipative Particle Dynamics (DPD). Different cell morphologies (sickle, granular, elongated shapes) typically observed in in vitro and in vivo are constructed and the deviations from the biconcave shape is quantified by the Asphericity and Elliptical shape factors. The rheology of sickle blood is studied in both shear and pipe flow systems. The flow resistance obtained from both systems exhibits a larger value than the healthy blood flow due to the abnormal cell properties. However, the vaso-occulusion phenomenon, reported in a recent microfluid experiment, is not observed in the pipe flow system unless the adhesive interactions between sickle blood cells and endothelium properly introduced into the model.

  19. Margination of white blood cells - a computational approach by a hydrodynamic phase field model

    CERN Document Server

    Marth, Wieland

    2015-01-01

    We numerically investigate margination of white blood cells and demonstrate the dependency on a number of conditions including hematocrit, the deformability of the cells and the Reynolds number. A detailed mesoscopic hydrodynamic Helfrich-type model is derived, validated and used for the simulations to provides a quantitative description of the margination of white blood cells. Previous simulation results, obtained with less detailed models, could be confirmed, e.g. the largest probability of margination of white blood cells at an intermediate range of hematocrit values and a decreasing tendency with increasing deformability. The consideration of inertia effects, which become of relevance in small vessels, also shows a dependency and leads to less pronounced margination of white blood cells with increasing Reynolds number.

  20. Association between calcium intake, parathormone levels and blood pressure during pregnancy

    Directory of Open Access Journals (Sweden)

    Anibal Nieto

    2009-06-01

    Full Text Available Purpose: To evaluate the association between calcium intake from diet, calciotropic hormones (PTH, PTH-rp, vasoactive regulators (endothelin, nitric oxide and blood pressure levels during pregnancy, birth and puerperium.Method: In a prospective study 149 healthy normotensive primigravidas were followed-up from 15 weeks of gestation to puerperium. Daily calcium intake, calciuria, PTH, PTH-rp, endothelin, nitrite-nitrate, and Holter Test were assessed. Linear regression models were performed to evaluate the association between calcium intake, blood pressure levels and the laboratory tests. Multivariate regression models were performed to control potential confounders.Results: A significant increase of calcium intake during pregnancy was observed (931±301 mg/day to 1,195±467 mg/day, p<0.001. Plasma PTH-rp, endothelin, and nitrite-nitrate levels did not change during pregnancy. Among the women 38 (25.4% had low calcium intake (<800 mg/day with a larger increase of systolic and diastolic blood pressure during pregnancy (p=0.04 birth (p=0.006 and puerperium (p=0.01. After adjusting for other factors the multivariate analyses showed statistical association between low calcium intake, high parathormone levels and high systolic blood pressure levels during pregnancy (p=0.002.Conclusion: Low calcium intake during pregnancy is associated with a larger increase of systolic blood pressure and high parathormone levels.

  1. Non-Newtonian model study for blood flow through a tapered artery with a stenosis

    Directory of Open Access Journals (Sweden)

    Noreen Sher Akbar

    2016-03-01

    Full Text Available The blood flow through a tapered artery with a stenosis is analyzed, assuming the blood as tangent hyperbolic fluid model. The resulting nonlinear implicit system of partial differential equations is solved analytically with the help of perturbation method. The expressions for shear stress, velocity, flow rate, wall shear stress and longitudinal impedance are obtained. The variations of power law index m, Weissenberg number We, shape of stenosis n and stenosis size δ are discussed different type of tapered arteries.

  2. Longer Breastfeeding in Infancy Decreases Systolic Hypertension Risk in Young Adults

    Directory of Open Access Journals (Sweden)

    Rak Karolina

    2016-07-01

    Full Text Available Many studies show that breastfeeding is associated with numerous direct and indirect health benefits for children in later life, although the relationship between breastfeeding and cardiovascular risk is still equivocal. The aim of this study was to investigate the relationship between duration of breastfeeding and cardiovascular risk in young adults. The cross-sectional study was conducted on a group of 128 volunteers (71 women and 57 men at the age of 19 years. It consisted of a questionnaire, together with anthropometric and blood pressure measurements. It was demonstrated that 90.3% of the participants had been breastfed and the mean duration of breastfeeding was 8.8±7.6 months. Participants who were breastfed for longer than six months had a significantly lower systolic blood pressure than those breastfed for less than six months. Results of analyses were consistent for the female group, the male group and the combined group. The results suggest that breastfeeding for longer than six months decreases systolic hypertension risk in young adults. The promotion of breastfeeding may decrease the rate of cardiovascular disease and thus improve health status of the population.

  3. Study of light scattering by a granulated coated sphere - a model of granulated blood cells

    NARCIS (Netherlands)

    M.A. Yurkin; D. de Kanter; A.G. Hoekstra

    2008-01-01

    We performed extensive simulations of light scattering by granulated coated sphere model using the discrete dipole approximation and varying model parameters in the ranges of sizes and refractive indices of granulated blood cells. We compared these results with predictions of Maxwell-Garnett effecti

  4. Mathematical model of the chromatin structure of the nuclei of blood cells

    Science.gov (United States)

    Nikitaev, V. G.; Nagornov, O. V.; Pronichev, A. N.; Dmitrieva, V. V.; Polyakov, E. V.

    2017-01-01

    This paper describes the model of images of the nuclei of blood cells for research informative texture features in the diagnostics of acute leukemias on the basis of computer microscopy. The proposed model allows to simulate the structure of chromatin and factors distorting the signal in the formation of image.

  5. MATHEMATICAL MODELING OF WELDING BLOOD VESSELS BY ELECTROSURGERY FORCEPS

    Directory of Open Access Journals (Sweden)

    Yarova S.O.

    2016-02-01

    Full Text Available Electrosurgical instruments for the coagulation of biological tissue is used in almost all surgical operations. SolidWorks modeling allows to obtain the distribution of the mechanical stresses, displacements and strains. The design of all types of forceps are made so that the electrodes were positioned at an angle. This improves the grip of the tissue, but leads to uneven compression. Bending the jaws of the forceps improves the uniformity of the stress distribution

  6. Influence of renal impairment on myocardial function in outpatients with systolic heart failure

    DEFF Research Database (Denmark)

    Bosselmann, Helle; Tønder, Niels; Sölétormos, György

    2014-01-01

    BACKGROUND: Renal dysfunction (RD) is associated with poor outcome in systolic heart failure (HF). Left ventricular ejection fraction (LVEF) is not depressed to a greater extent in patients with RD compared to patients with normal renal function, but it is relatively unknown whether other measures...... of myocardial function are impaired by RD. The objective of the present study is to evaluate whether RD in systolic HF is associated with excessive impairment of myocardial function, evaluated by strain analysis and cardiac biomarkers. METHODS: Patients with LVEF ... models were developed to evaluate the associations between eGFR groups, echocardiographic measures and cardiac biomarkers. RESULTS: A total of 149 patients participated in the study. Median age was 69 years, 26% were female; LVEF was 33%. Patients with a low eGFR were older (P

  7. Blood pressure in young adulthood and residential greenness in the early-life environment of twins.

    Science.gov (United States)

    Bijnens, Esmée M; Nawrot, Tim S; Loos, Ruth Jf; Gielen, Marij; Vlietinck, Robert; Derom, Catherine; Zeegers, Maurice P

    2017-06-05

    Previous research shows that, besides risk factors in adult life, the early-life environment can influence blood pressure and hypertension in adults. However, the effects of residential traffic exposure and residential greenness in the early-life on blood pressure in young adulthood are currently unknown. Ambulatory (24-h) blood pressures of 278 twins (132 pairs) of the East Flanders Prospective Twins Study were obtained at the age of 18 to 25 years. Prenatal and adulthood residential addresses were geocoded and used to assign prenatal and postnatal traffic and greenness indicators. Mixed modelling was performed to investigate blood pressure in association with greenness while adjusting for potential confounding factors. Night-time systolic blood pressure was inversely associated with greenness at the residential address in twins living at the same address their entire life (non-movers, n = 97, 34.9%). An interquartile increase in residential greenness exposure (1000 m radius) was associated with a 3.59 mmHg (95% CI: -6.0 to -1.23; p = 0.005) lower adult night systolic blood pressure. Among twins who were living at a different address than their birth address at time of the measurement (n = 181, 65.1%), night-time blood pressure was inversely associated with residential surrounding greenness at adult age as well as with residential greenness in early-life. However after additional adjustment for residential greenness exposure in adulthood, only residential greenness exposure in early-life was significantly associated with night systolic blood pressure. While no significant effect of adult residential greenness with adult blood pressure was observed, while accounting for the early-life greenness exposure. Lower residential greenness in the early-life environment was independently associated with a higher adult blood pressure. This indicates that residential greenness has persistent effects on blood pressure.

  8. Association Between Early Life Growth and Blood Pressure Trajectories in Black South African Children.

    Science.gov (United States)

    Kagura, Juliana; Adair, Linda S; Munthali, Richard J; Pettifor, John M; Norris, Shane A

    2016-11-01

    Early growth is associated with blood pressure measured on one occasion, but whether early life growth patterns are associated with longitudinal blood pressure trajectories is under-researched. Therefore, we sought to examine the association between early growth and blood pressure trajectories from childhood to adulthood. Blood pressure was measured on 7 occasions between ages 5 and 18 years in the Birth to Twenty cohort study, and conditional variables for growth in infancy and mid-childhood were computed from anthropometric measures (n=1937, 52% girls). We used a group-based trajectory modeling approach to identify distinct height-adjusted blood pressure trajectories and then tested their association with growth between birth and mid-childhood adjusting for several covariates. Three trajectory groups were identified for systolic and diastolic blood pressure: lower, middle, and upper in boys and girls, separately. In boys, predictors of the middle or upper systolic blood pressure trajectories versus the lower trajectory were in birth weight (odds ratio 0.75 [95% confidence interval 0.58-0.96] per SD) and relative weight gain in infancy (4.11 [1.25-13.51] per SD). In girls, greater relative weight gain and linear growth in both infancy and mid-childhood were consistently associated with an almost 2-fold higher likelihood of being in the upper versus lower systolic blood pressure trajectory. The associations for the diastolic blood pressure trajectories were inconsistent. These findings emphasize the importance of identifying children at risk of progression to high blood pressure. Accelerated growth in infancy and mid-childhood may be a key target for early life intervention in prevention of elevated blood pressure progression. © 2016 American Heart Association, Inc.

  9. Predicting future blood supply and demand in Japan with a Markov model: application to the sex- and age-specific probability of blood donation.

    Science.gov (United States)

    Akita, Tomoyuki; Tanaka, Junko; Ohisa, Masayuki; Sugiyama, Aya; Nishida, Kazuo; Inoue, Shingo; Shirasaka, Takuma

    2016-11-01

    Simulation studies were performed to predict the future supply and demand for blood donations, and future shortfalls. Using data from all donations in 2006 to 2009, the Markov model was applied to estimate future blood donations until 2050. Based on data concerning the actual use of blood products, the number of blood products needed was estimated based on future population projections. We estimated that the number of blood donations increased from 5,020,000 in 2008 to 5,260,000 in 2012, but will decrease to 4,770,000 units by 2025. In particular, the number of donors in their 20s and 30s decreased every year. Moreover, the number of donations required to supply blood products would have been increased from 5,390,000 in 2012 to 5,660,000 units in 2025. Thus, the estimated shortfall of blood donations is expected to increase each year from 140,000 in 2012 to 890,000 in 2025 and then more than double to 1,670,000 in 2050. If the current blood donation behaviors continue, a shortfall of blood availability is likely to occur in Japan. Insufficient blood donations are mainly related to a projected reduction in population of 20 to 30 year olds, a significant group of donors. Thus, it is crucial to recruit and retain new donors and to develop recommendations for proper use of blood products to minimize unnecessary use. This study provides useful information that can be used by governments to help ensure the adequacy of the blood supply through promoting donations and conserving blood resources. © 2016 AABB.

  10. A study of systolic time intervals in lepra reaction.

    Science.gov (United States)

    Zawar, P B; Chawhan, R N; Mahajani, V V

    1983-10-01

    Systolic time intervals (STI) were measured in 20 control subjects and 20 cases of lepromatous leprosy in lepra reaction. Significant differences in the pre-ejection period (PEP), PEP/LVET and isovolumic contraction (IVCT) were observed between the groups. The abnormalities of STI observed in patients of lepra reaction are characteristic of left ventricular dysfunction in patients of lepra reaction.

  11. Modeling of the blood rheology in steady-state shear flows

    Energy Technology Data Exchange (ETDEWEB)

    Apostolidis, Alex J.; Beris, Antony N., E-mail: beris@udel.edu [Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716 (United States)

    2014-05-15

    We undertake here a systematic study of the rheology of blood in steady-state shear flows. As blood is a complex fluid, the first question that we try to answer is whether, even in steady-state shear flows, we can model it as a rheologically simple fluid, i.e., we can describe its behavior through a constitutive model that involves only local kinematic quantities. Having answered that question positively, we then probe as to which non-Newtonian model best fits available shear stress vs shear-rate literature data. We show that under physiological conditions blood is typically viscoplastic, i.e., it exhibits a yield stress that acts as a minimum threshold for flow. We further show that the Casson model emerges naturally as the best approximation, at least for low and moderate shear-rates. We then develop systematically a parametric dependence of the rheological parameters entering the Casson model on key physiological quantities, such as the red blood cell volume fraction (hematocrit). For the yield stress, we base our description on its critical, percolation-originated nature. Thus, we first determine onset conditions, i.e., the critical threshold value that the hematocrit has to have in order for yield stress to appear. It is shown that this is a function of the concentration of a key red blood cell binding protein, fibrinogen. Then, we establish a parametric dependence as a function of the fibrinogen and the square of the difference of the hematocrit from its critical onset value. Similarly, we provide an expression for the Casson viscosity, in terms of the hematocrit and the temperature. A successful validation of the proposed formula is performed against additional experimental literature data. The proposed expression is anticipated to be useful not only for steady-state blood flow modeling but also as providing the starting point for transient shear, or more general flow modeling.

  12. Pregnancy hypertension and umbilical cord blood lead levels

    Energy Technology Data Exchange (ETDEWEB)

    Rabinowitz, M.; Bellinger, D.; Leviton, A. (Children' s Hospital, Boston, MA (USA)); Needleman, H. (Children' s Hospital, Pittsburgh, PA (USA)); Schoenbaum, S. (Harvard Community Health Plan, Brookline Village, MA (USA))

    Pregnancy hypertension, blood pressure during labor, and the umbilical cord blood lead concentration were assessed in 3,851 women for whom additional demographic, medical, and personal information was available. Lead levels correlated with both systolic and diastolic blood pressure during labor. The incidence of clinically defined pregnancy hypertension, nearly 11% overall, increased with lead level. A series of multivariate models of pregnancy hypertension and of systolic blood pressure as a function of maternal age, parity, hematocrit, ponderal index, race, season, and diabetes were improved by including lead as a predictor variable. These other risk factors are not affected by the lead term. The relative risk for pregnancy hypertension doubles when lead increases from 2 to 15 {mu}g/dl. The effect is statistically strong, with a magnitude of about 3 mm for a 10 {mu}g/dl range, about the same magnitude associated with diabetes. At these observed levels (mean blood lead = 6.0 {mu}g/dl, SD = 3.3, range 0 > 35), not currently recognized as overtly toxic, lead has a small but demonstrable association with pregnancy hypertension and blood pressure at the time of delivery, but not with pre-eclampsia nor toxemia. Although this association is not likely to influence the clinical management of hypertension, it indicates that lead at typical contemporary urban levels, does effect multiple physiological functions.

  13. Blood pressure and falls in community-dwelling people aged 60 years and older in the VHM&PP cohort

    Science.gov (United States)

    2013-01-01

    Background Falls are one of the major health problems in old people. Different risk factors were identified but only few epidemiological studies analysed the influence of conventionally measured blood pressure on falls. The objective of our study was to investigate the relationship between systolic and diastolic blood pressure and falls. Methods In 3,544 community-dwelling Austrian women and men aged 60 years and older, data on falls within the previous three months were collected by questionnaire. Blood pressure was measured by general practitioners within the Vorarlberg Health Monitoring and Prevention Programme (VHM&PP) 90 to 1095 days before the fall assessment. A multiple logistic regression analysis was conducted. The models were stratified by gender and adjusted by age, number of medical conditions and subjective feeling of illness. Results In total, 257 falls in 3,544 persons were reported. In women, high systolic and diastolic blood pressure was associated with a decreased risk of falls. An increase of systolic blood pressure by 10 mmHg and of diastolic blood pressure by 5 mmHg reduced the risk of falling by 9% (OR 0.91, 95% Cl 0.84-0.98) and 8% (OR 0.92, 95% Cl 0.85-0.99), respectively. In men, an increased risk of falls was observed in participants with low systolic or low diastolic blood pressure. Conclusions Blood pressure was associated with the risk of falls. Hypertensive values decreased the risk in women and low blood pressure increased the risk in men. PMID:23692779

  14. Paving the way towards complex blood-brain barrier models using pluripotent stem cells

    DEFF Research Database (Denmark)

    Lauschke, Karin; Frederiksen, Lise; Hall, Vanessa Jane

    2017-01-01

    to the unique tightness and selective permeability of the BBB and has been shown to be disrupted in many diseases and brain disorders, such as, vascular dementia, stroke, multiple sclerosis and Alzheimer's disease. Given the progress that pluripotent stem cells (PSCs) have made in the last two decades......A tissue with great need to be modelled in vitro is the blood-brain barrier (BBB). The BBB is a tight barrier that covers all blood vessels in the brain and separates the brain microenvironment from the blood system. It consists of three cell types (neurovascular unit (NVU)) that contribute......, it is now possible to produce many cell types from the BBB and even partially recapitulate this complex tissue in vitro. In this review, we summarize the most recent developments in PSC differentiation and modelling of the BBB. We also suggest how patient-specific human induced PSCs could be used to model...

  15. Polymer-based blood vessel models with micro-temperature sensors in EVE

    Science.gov (United States)

    Mizoshiri, Mizue; Ito, Yasuaki; Hayakawa, Takeshi; Maruyama, Hisataka; Sakurai, Junpei; Ikeda, Seiichi; Arai, Fumihito; Hata, Seiichi

    2017-04-01

    Cu-based micro-temperature sensors were directly fabricated on poly(dimethylsiloxane) (PDMS) blood vessel models in EVE using a combined process of spray coating and femtosecond laser reduction of CuO nanoparticles. CuO nanoparticle solution coated on a PDMS blood vessel model are thermally reduced and sintered by focused femtosecond laser pulses in atmosphere to write the sensors. After removing the non-irradiated CuO nanoparticles, Cu-based microtemperature sensors are formed. The sensors are thermistor-type ones whose temperature dependences of the resistance are used for measuring temperature inside the blood vessel model. This fabrication technique is useful for direct-writing of Cu-based microsensors and actuators on arbitrary nonplanar substrates.

  16. Simulation-optimization model for production planning in the blood supply chain.

    Science.gov (United States)

    Osorio, Andres F; Brailsford, Sally C; Smith, Honora K; Forero-Matiz, Sonia P; Camacho-Rodríguez, Bernardo A

    2016-06-04

    Production planning in the blood supply chain is a challenging task. Many complex factors such as uncertain supply and demand, blood group proportions, shelf life constraints and different collection and production methods have to be taken into account, and thus advanced methodologies are required for decision making. This paper presents an integrated simulation-optimization model to support both strategic and operational decisions in production planning. Discrete-event simulation is used to represent the flows through the supply chain, incorporating collection, production, storing and distribution. On the other hand, an integer linear optimization model running over a rolling planning horizon is used to support daily decisions, such as the required number of donors, collection methods and production planning. This approach is evaluated using real data from a blood center in Colombia. The results show that, using the proposed model, key indicators such as shortages, outdated units, donors required and cost are improved.

  17. A computational model of the fetal circulation to quantify blood redistribution in intrauterine growth restriction.

    Directory of Open Access Journals (Sweden)

    Patricia Garcia-Canadilla

    2014-06-01

    Full Text Available Intrauterine growth restriction (IUGR due to placental insufficiency is associated with blood flow redistribution in order to maintain delivery of oxygenated blood to the brain. Given that, in the fetus the aortic isthmus (AoI is a key arterial connection between the cerebral and placental circulations, quantifying AoI blood flow has been proposed to assess this brain sparing effect in clinical practice. While numerous clinical studies have studied this parameter, fundamental understanding of its determinant factors and its quantitative relation with other aspects of haemodynamic remodeling has been limited. Computational models of the cardiovascular circulation have been proposed for exactly this purpose since they allow both for studying the contributions from isolated parameters as well as estimating properties that cannot be directly assessed from clinical measurements. Therefore, a computational model of the fetal circulation was developed, including the key elements related to fetal blood redistribution and using measured cardiac outflow profiles to allow personalization. The model was first calibrated using patient-specific Doppler data from a healthy fetus. Next, in order to understand the contributions of the main parameters determining blood redistribution, AoI and middle cerebral artery (MCA flow changes were studied by variation of cerebral and peripheral-placental resistances. Finally, to study how this affects an individual fetus, the model was fitted to three IUGR cases with different degrees of severity. In conclusion, the proposed computational model provides a good approximation to assess blood flow changes in the fetal circulation. The results support that while MCA flow is mainly determined by a fall in brain resistance, the AoI is influenced by a balance between increased peripheral-placental and decreased cerebral resistances. Personalizing the model allows for quantifying the balance between cerebral and peripheral

  18. A computational model of the fetal circulation to quantify blood redistribution in intrauterine growth restriction.

    Science.gov (United States)

    Garcia-Canadilla, Patricia; Rudenick, Paula A; Crispi, Fatima; Cruz-Lemini, Monica; Palau, Georgina; Camara, Oscar; Gratacos, Eduard; Bijnens, Bart H; Bijens, Bart H

    2014-06-01

    Intrauterine growth restriction (IUGR) due to placental insufficiency is associated with blood flow redistribution in order to maintain delivery of oxygenated blood to the brain. Given that, in the fetus the aortic isthmus (AoI) is a key arterial connection between the cerebral and placental circulations, quantifying AoI blood flow has been proposed to assess this brain sparing effect in clinical practice. While numerous clinical studies have studied this parameter, fundamental understanding of its determinant factors and its quantitative relation with other aspects of haemodynamic remodeling has been limited. Computational models of the cardiovascular circulation have been proposed for exactly this purpose since they allow both for studying the contributions from isolated parameters as well as estimating properties that cannot be directly assessed from clinical measurements. Therefore, a computational model of the fetal circulation was developed, including the key elements related to fetal blood redistribution and using measured cardiac outflow profiles to allow personalization. The model was first calibrated using patient-specific Doppler data from a healthy fetus. Next, in order to understand the contributions of the main parameters determining blood redistribution, AoI and middle cerebral artery (MCA) flow changes were studied by variation of cerebral and peripheral-placental resistances. Finally, to study how this affects an individual fetus, the model was fitted to three IUGR cases with different degrees of severity. In conclusion, the proposed computational model provides a good approximation to assess blood flow changes in the fetal circulation. The results support that while MCA flow is mainly determined by a fall in brain resistance, the AoI is influenced by a balance between increased peripheral-placental and decreased cerebral resistances. Personalizing the model allows for quantifying the balance between cerebral and peripheral-placental remodeling

  19. Consequences of Transfusing Blood Components in Patients With Trauma: A Conceptual Model.

    Science.gov (United States)

    Jones, Allison R; Frazier, Susan K

    2017-04-01

    Transfusion of blood components is often required in resuscitation of patients with major trauma. Packed red blood cells and platelets break down and undergo chemical changes during storage (known as the storage lesion) that lead to an inflammatory response once the blood components are transfused to patients. Although some evidence supports a detrimental association between transfusion and a patient's outcome, the mechanisms connecting transfusion of stored components to outcomes remain unclear. The purpose of this review is to provide critical care nurses with a conceptual model to facilitate understanding of the relationship between the storage lesion and patients' outcomes after trauma; outcomes related to trauma, hemorrhage, and blood component transfusion are grouped according to those occurring in the short-term (≤30 days) and the long-term (>30 days). Complete understanding of these clinical implications is critical for practitioners in evaluating and treating patients given transfusions after traumatic injury.

  20. Development of class model based on blood biochemical parameters as a diagnostic tool of PSE meat.

    Science.gov (United States)

    Qu, Daofeng; Zhou, Xu; Yang, Feng; Tian, Shiyi; Zhang, Xiaojun; Ma, Lin; Han, Jianzhong

    2017-06-01

    A fast, sensitive and effective method based on the blood biochemical parameters for the detection of PSE meat was developed in this study. A total of 200 pigs were slaughtered in the same slaughterhouse. Meat quality was evaluated by measuring pH, electrical conductivity and color at 45min, 2h and 24h after slaughtering in M. longissimus thoracis et lumborum (LD). Blood biochemical parameters were determined in blood samples collected during carcass bleeding. Principal component analysis (PCA) biplot showed that high levels of exsanguination Creatine Kinase, Lactate Dehydrogenase, Aspertate aminotransferase, blood glucose and lactate were associated with the PSE meat, and the five biochemical parameters were found to be good indicators of PSE meat Discriminant function analysis (DFA) was able to clearly identify PSE meat using the five biochemical parameters as input data, and the class model is an effective diagnostic tool in pigs which can be used to detect the PSE meat and reduce economic loss for the company.

  1. Low Reynolds number turbulence modeling of blood flow in arterial stenoses.

    Science.gov (United States)

    Ghalichi, F; Deng, X; De Champlain, A; Douville, Y; King, M; Guidoin, R

    1998-01-01

    Moderate and severe arterial stenoses can produce highly disturbed flow regions with transitional and or turbulent flow characteristics. Neither laminar flow modeling nor standard two-equation models such as the kappa-epsilon turbulence ones are suitable for this kind of blood flow. In order to analyze the transitional or turbulent flow distal to an arterial stenosis, authors of this study have used the Wilcox low-Re turbulence model. Flow simulations were carried out on stenoses with 50, 75 and 86% reductions in cross-sectional area over a range of physiologically relevant Reynolds numbers. The results obtained with this low-Re turbulence model were compared with experimental measurements and with the results obtained by the standard kappa-epsilon model in terms of velocity profile, vortex length, wall shear stress, wall static pressure, and turbulence intensity. The comparisons show that results predicted by the low-Re model are in good agreement with the experimental measurements. This model accurately predicts the critical Reynolds number at which blood flow becomes transitional or turbulent distal an arterial stenosis. Most interestingly, over the Re range of laminar flow, the vortex length calculated with the low-Re model also closely matches the vortex length predicted by laminar flow modeling. In conclusion, the study strongly suggests that the proposed model is suitable for blood flow studies in certain areas of the arterial tree where both laminar and transitional/turbulent flows coexist.

  2. Testing a capacity-load model for hypertension: disentangling early and late growth effects on childhood blood pressure in a prospective birth cohort.

    Science.gov (United States)

    Grijalva-Eternod, Carlos S; Lawlor, Debbie A; Wells, Jonathan C K

    2013-01-01

    In 2005, it was estimated that hypertension affected 26.4% of the adult population worldwide. By 2025, it is predicted that it will affect about 60% of adults, a total of 1.56 billion. Both pre- and postnatal growth patterns have been associated with later blood pressure (BP), but in contrasting directions. These inconsistent associations of growth during different developmental periods merit elucidation. We tested a theoretical model treating birth weight as a marker of homeostatic metabolic capacity, and childhood height, lean mass and fat mass as independent indices of metabolic load. We predicted that decreased capacity and increased load would be independently associated with increased BP. Data from the ALSPAC cohort on growth from birth to 7 years, and body composition by dual-energy X-ray absorptiometry and BP at 9 years, were analysed (n = 6579). Data were expressed as standard deviation scores (SDS) or standardised regression residuals (SRR). BP was independently and positively associated with each of height, lean mass and fat mass. In a joint model systolic BP was positively associated with conditional weight velocity [males 0.40 (95%CI: 0.37-0.44) & females 0.44 (95%CI: 0.40-0.47) SDS/SRR], but not birth weight [0.00 (95%CI: -0.03-0.04) & 0.03 (95%CI: -0.01-0.07) SDS/SDS]. Adjusting for height, lean mass and fat mass, the association of systolic BP and conditional weight velocity attenuated [0.00(95%CI: -0.09-0.08) & -0.06(95%CI: -0.14-0.03) SDS/SRR], whereas that with birth weight became negative [-0.10 (95%CI: -0.14-0.06) & -0.09 (95%CI: -0.13-0.05) SDS/SDS]. Similar results were obtained for diastolic BP and pulse pressure. Consistent with our theoretical model, high metabolic load relative to metabolic capacity is associated with increased BP. Our data demonstrate the contribution of different growth and body composition components to BP variance, and clarify the developmental aetiology of hypertension.

  3. Testing a capacity-load model for hypertension: disentangling early and late growth effects on childhood blood pressure in a prospective birth cohort.

    Directory of Open Access Journals (Sweden)

    Carlos S Grijalva-Eternod

    Full Text Available In 2005, it was estimated that hypertension affected 26.4% of the adult population worldwide. By 2025, it is predicted that it will affect about 60% of adults, a total of 1.56 billion. Both pre- and postnatal growth patterns have been associated with later blood pressure (BP, but in contrasting directions. These inconsistent associations of growth during different developmental periods merit elucidation. We tested a theoretical model treating birth weight as a marker of homeostatic metabolic capacity, and childhood height, lean mass and fat mass as independent indices of metabolic load. We predicted that decreased capacity and increased load would be independently associated with increased BP.Data from the ALSPAC cohort on growth from birth to 7 years, and body composition by dual-energy X-ray absorptiometry and BP at 9 years, were analysed (n = 6579. Data were expressed as standard deviation scores (SDS or standardised regression residuals (SRR. BP was independently and positively associated with each of height, lean mass and fat mass. In a joint model systolic BP was positively associated with conditional weight velocity [males 0.40 (95%CI: 0.37-0.44 & females 0.44 (95%CI: 0.40-0.47 SDS/SRR], but not birth weight [0.00 (95%CI: -0.03-0.04 & 0.03 (95%CI: -0.01-0.07 SDS/SDS]. Adjusting for height, lean mass and fat mass, the association of systolic BP and conditional weight velocity attenuated [0.00(95%CI: -0.09-0.08 & -0.06(95%CI: -0.14-0.03 SDS/SRR], whereas that with birth weight became negative [-0.10 (95%CI: -0.14-0.06 & -0.09 (95%CI: -0.13-0.05 SDS/SDS]. Similar results were obtained for diastolic BP and pulse pressure.Consistent with our theoretical model, high metabolic load relative to metabolic capacity is associated with increased BP. Our data demonstrate the contribution of different growth and body composition components to BP variance, and clarify the developmental aetiology of hypertension.

  4. Numerical Investigation of Pulsatile Blood Flow in a Bifurcation Model with a Non-Planar Branch: The Effect of Different Bifurcation Angles and Non-Planar Branch

    Directory of Open Access Journals (Sweden)

    Omid Arjmandi-Tash

    2012-12-01

    Full Text Available Introduction: Atherosclerosis is a focal disease that susceptibly forms near bifurcations, anastomotic joints, side branches, and curved vessels along the arterial tree. In this study, pulsatile blood flow in a bifurcation model with a non-planar branch is investigated. Methods: Wall shear stress (WSS distributions along generating lines on vessels for different bifurcation angles are calculated during the pulse cycle. Results: The WSS at the outer side of the bifurcation plane vanishes especially for higher bifurcation angles but by increasing the bifurcation angle low WSS region squeezes. At the systolic phase there is a high possibility of formation of a separation region at the outer side of bifurcation plane for all the cases. WSS peaks exist on the inner side of bifurcation plane near the entry section of daughter vessels and these peaks drop as bifurcation angle is increased. Conclusion: It was found that non-planarity of the daughter vessel lowers the minimum WSS at the outer side of the bifurcation and increases the maximum WSS at the inner side. So it seems that the formation of atherosclerotic plaques at bifurcation region in direction of non-planar daughter vessel is more risky.

  5. Predicting dynamics and rheology of blood flow: A comparative study of multiscale and low-dimensional models of red blood cells

    Science.gov (United States)

    Pan, Wenxiao; Fedosov, Dmitry A.; Caswell, Bruce; Karniadakis, George Em

    2011-01-01

    We compare the predictive capability of two mathematical models for red blood cells (RBCs) focusing on blood flow in capillaries and arterioles. Both RBC models as well as their corresponding blood flows are based on the dissipative particle dynamics (DPD) method, a coarse-grained molecular dynamics approach. The first model employs a multiscale description of the RBC (MS-RBC), with its membrane represented by hundreds or even thousands of DPD-particles connected by springs into a triangular network in combination with out-of-plane elastic bending resistance. Extra dissipation within the network accounts for membrane viscosity, while the characteristic biconcave RBC shape is achieved by imposition of constraints for constant membrane area and constant cell volume. The second model is based on a low-dimensional description (LD-RBC) constructed as a closed torus-like ring of only 10 large DPD colloidal particles. They are connected into a ring by worm-like chain (WLC) springs combined with bending resistance. The LD-RBC model can be fitted to represent the entire range of nonlinear elastic deformations as measured by optical-tweezers for healthy and for infected RBCs in malaria. MS-RBCs suspensions model the dynamics and rheology of blood flow accurately for any vessel size but this approach is computationally expensive for vessel diameters above 100 microns. Surprisingly, the much more economical suspensions of LD-RBCs also capture the blood flow dynamics and rheology accurately except for small-size vessels comparable to RBC diameter. In particular, the LD-RBC suspensions are shown to properly capture the experimental data for the apparent viscosity of blood and its cell-free layer (CFL) in tube flow. Taken together, these findings suggest a hierarchical approach in modeling blood flow in the arterial tree, whereby the MS-RBC model should be employed for capillaries and arterioles below 100 microns, the LD-RBC model for arterioles, and the continuum description for

  6. Simplification of a pharmacokinetic model for red blood cell methotrexate disposition.

    Science.gov (United States)

    Pan, Shan; Korell, Julia; Stamp, Lisa K; Duffull, Stephen B

    2015-12-01

    A pharmacokinetic (PK) model is available for describing the time course of the concentrations of methotrexate (MTX or MTXGlu1) and its active polyglutamated metabolites (MTXGlu2-5) in red blood cells (RBCs). In this study, we aimed to simplify the MTX PK model and to optimise the blood sampling schedules for use in future studies. A proper lumping technique was used to simplify the original MTX RBC PK model. The sum of predicted RBC MTXGlu3-5 concentrations in both the simplified and original models was compared. The sampling schedules for MTXGlu3-5 or all MTX polyglutamates in RBCs were optimised using the Population OPTimal design (POPT) software. The MTX RBC PK model was simplified into a three-state model. The maximum of the absolute value of relative difference in the sum of predicted RBC MTXGlu3-5 concentrations over time was 6.3 %. A five blood sample design was identified for estimating parameters of the simplified model. This study illustrates the application of model simplification processes to an existing model for MTX RBC PK. The same techniques illustrated in our study may be adopted by other studies with similar interest.

  7. Intrastriatal injection of autologous blood or clostridial collagenase as murine models of intracerebral hemorrhage.

    Science.gov (United States)

    Lei, Beilei; Sheng, Huaxin; Wang, Haichen; Lascola, Christopher D; Warner, David S; Laskowitz, Daniel T; James, Michael L

    2014-07-03

    Intracerebral hemorrhage (ICH) is a common form of cerebrovascular disease and is associated with significant morbidity and mortality. Lack of effective treatment and failure of large clinical trials aimed at hemostasis and clot removal demonstrate the need for further mechanism-driven investigation of ICH. This research may be performed through the framework provided by preclinical models. Two murine models in popular use include intrastriatal (basal ganglia) injection of either autologous whole blood or clostridial collagenase. Since, each model represents distinctly different pathophysiological features related to ICH, use of a particular model may be selected based on what aspect of the disease is to be studied. For example, autologous blood injection most accurately represents the brain's response to the presence of intraparenchymal blood, and may most closely replicate lobar hemorrhage. Clostridial collagenase injection most accurately represents the small vessel rupture and hematoma evolution characteristic of deep hemorrhages. Thus, each model results in different hematoma formation, neuroinflammatory response, cerebral edema development, and neurobehavioral outcomes. Robustness of a purported therapeutic intervention can be best assessed using both models. In this protocol, induction of ICH using both models, immediate post-operative demonstration of injury, and early post-operative care techniques are demonstrated. Both models result in reproducible injuries, hematoma volumes, and neurobehavioral deficits. Because of the heterogeneity of human ICH, multiple preclinical models are needed to thoroughly explore pathophysiologic mechanisms and test potential therapeutic strategies.

  8. Two-Fluid Mathematical Models for Blood Flow in Stenosed Arteries: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Sankar DS

    2009-01-01

    Full Text Available The pulsatile flow of blood through stenosed arteries is analyzed by assuming the blood as a two-fluid model with the suspension of all the erythrocytes in the core region as a non-Newtonian fluid and the plasma in the peripheral layer as a Newtonian fluid. The non-Newtonian fluid in the core region of the artery is assumed as a (i Herschel-Bulkley fluid and (ii Casson fluid. Perturbation method is used to solve the resulting system of non-linear partial differential equations. Expressions for various flow quantities are obtained for the two-fluid Casson model. Expressions of the flow quantities obtained by Sankar and Lee (2006 for the two-fluid Herschel-Bulkley model are used to get the data for comparison. It is found that the plug flow velocity and velocity distribution of the two-fluid Casson model are considerably higher than those of the two-fluid Herschel-Bulkley model. It is also observed that the pressure drop, plug core radius, wall shear stress and the resistance to flow are significantly very low for the two-fluid Casson model than those of the two-fluid Herschel-Bulkley model. Hence, the two-fluid Casson model would be more useful than the two-fluid Herschel-Bulkley model to analyze the blood flow through stenosed arteries.

  9. The association between changes in blood pressure components and incident cardiovascular diseases.

    Science.gov (United States)

    Parizadeh, Donna; Ghahvehchian, Hosein; Asgari, Samaneh; Momenan, Amir Abbas; Azizi, Fereidoun; Hadaegh, Farzad

    2017-07-14

    To determine the association of changes in blood pressure (BP) components between baseline examination (1999-2001) and a second visit (2002-2005) with incident cardiovascular diseases (CVD). In 3569 (2048 female) Iranian subjects ≥30 y, systolic BP, diastolic BP, mean arterial pressure (MAP) and pulse pressure (PP) were evaluated in two consecutive visits. Subjects were then followed for cardiovascular events. Multivariate sex-adjusted Cox Proportional-Hazards models were built for each BP component's change, and further adjusted for baseline BP values, traditional cardiovascular risk factors, and their changes. During a median follow-up of 6.09 years after the second examination, 303 CVD cases occurred. A 1 SD increase in systolic BP, diastolic BP and MAP were significantly associated with 21%, 22%, and 95% increased CVD risk after adjustments for baseline values of BP components and other common risk factors (all p-values <0.05). Importantly, diastolic BP change resisted after further adjustment with systolic BP change (hazard ratio 1.21, CI 95% 1.05-1.39). PP change showed no significant association with CVD. In a middle-aged population, three-year rises in systolic BP, diastolic BP, MAP, but not PP were associated with increased incident CVD. The significant association between diastolic BP change and CVD was shown independent of systolic BP change.

  10. Speckle-Tracking analysis of left ventricular systolic function in the intensive care unit.

    Science.gov (United States)

    Cinotti, Raphaël; Delater, Adrien; Fortuit, Camille; Roquilly, Antoine; Mahé, Pierre-Joachim; Demeure-dit-Latte, Dominique; Asehnoune, Karim

    2015-01-01

    Speckle-tracking analysis is a new available tool in order to assess left ventricular function in cardiology. Its novelty relies on the technological ability to track natural acoustic markers (known as speckle) within the myocardium during the cardiac cycle. This technology allows the evaluation of myocardium strain during systole and diastole. To date, global longitudinal strain (GLS) has been extensively studied in cardiology. It is now well established that GLS is more sensitive than left ventricular ejection fraction with 2D echocardiography in detecting systolic function impairment. It is also superior to left ventricular ejection fraction in the prediction of major cardio-vascular events. In the intensive care unit (ICU) setting, data are scarce. In experimental model and human studies in septic shock, speckle-tracking analysis suggests that GSL is impaired along with preserved left ventricular ejection fraction. Recent data also suggest that GLS impairment could predict in-ICU mortality in septic shock. In severe subarachnoid haemorrhage patients, speckle-tracking analysis could be more sensitive in detecting stress cardiomyopathy. However, there are many gaps to fill in the critically ill patient. For instance, the influence of mechanical ventilation on GLS is not fully elucidated, and there are, to date, too few data to exactly assess potential GLS alterations on the patient's outcome. Nonetheless, this new tool provides objective and sensitive data with acceptable intra and inter-observer variability and may be of primary interest in the evaluation of left-ventricular systolic function in the ICU.

  11. Testing of models of flow-induced hemolysis in blood flow through hypodermic needles.

    Science.gov (United States)

    Chen, Yangsheng; Kent, Timothy L; Sharp, M Keith

    2013-03-01

    Hemolysis caused by flow in hypodermic needles interferes with a number of tests on blood samples drawn by venipuncture, including assays for metabolites, electrolytes, and enzymes, causes discomfort during dialysis sessions, and limits transfusion flow rates. To evaluate design modifications to address this problem, as well as hemolysis issues in other cardiovascular devices, computational fluid dynamics (CFD)-based prediction of hemolysis has potential for reducing the time and expense for testing of prototypes. In this project, three CFD-integrated blood damage models were applied to flow-induced hemolysis in 16-G needles and compared with experimental results, which demonstrated that a modified needle with chamfered entrance increased hemolysis, while a rounded entrance decreased hemolysis, compared with a standard needle with sharp entrance. After CFD simulation of the steady-state velocity field, the time histories of scalar stress along a grid of streamlines were calculated. A strain-based cell membrane failure model and two empirical power-law blood damage models were used to predict hemolysis on each streamline. Total hemolysis was calculated by weighting the predicted hemolysis along each streamline by the flow rate along each streamline. The results showed that only the strain-based blood damage model correctly predicted increased hemolysis in the beveled needle and decreased hemolysis in the rounded needle, while the power-law models predicted the opposite trends. © 2013, Copyright the Authors. Artificial Organs © 2013, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  12. Modeling the Behavior of Red Blood Cells within the Caudal Vein Plexus of Zebrafish

    Science.gov (United States)

    Djukic, Tijana R.; Karthik, Swapna; Saveljic, Igor; Djonov, Valentin; Filipovic, Nenad

    2016-01-01

    Due to the important biological role of red blood cells (RBCs) in vertebrates, the analysis of reshaping and dynamics of RBCs motion is a critical issue in physiology and biomechanics. In this paper the behavior of RBCs within the immature capillary plexus during embryonic development of zebrafish has been analyzed. Relying on the fact that zebrafish embryos are small and optically transparent, it is possible to image the blood flow. In this way the anatomy of blood vessels is monitored along with the circulation throughout their development. Numerical simulations were performed using a specific numerical model that combines fluid flow simulation, modeling of the interaction of individual RBCs immersed in blood plasma with the surrounding fluid and modeling the deformation of individual cells. The results of numerical simulations are in accordance with the in vivo observed region of interest within the caudal vein plexus of the zebrafish embryo. Good agreement of results demonstrates the capabilities of the developed numerical model to predict and analyze the motion and deformation of RBCs in complex geometries. The proposed model (methodology) will help to elucidate different rheological and hematological related pathologies and finally to design better treatment strategies. PMID:27774070

  13. Modeling the Behavior of Red Blood Cells within the Caudal Vein Plexus of Zebrafish.

    Science.gov (United States)

    Djukic, Tijana R; Karthik, Swapna; Saveljic, Igor; Djonov, Valentin; Filipovic, Nenad

    2016-01-01

    Due to the important biological role of red blood cells (RBCs) in vertebrates, the analysis of reshaping and dynamics of RBCs motion is a critical issue in physiology and biomechanics. In this paper the behavior of RBCs within the immature capillary plexus during embryonic development of zebrafish has been analyzed. Relying on the fact that zebrafish embryos are small and optically transparent, it is possible to image the blood flow. In this way the anatomy of blood vessels is monitored along with the circulation throughout their development. Numerical simulations were performed using a specific numerical model that combines fluid flow simulation, modeling of the interaction of individual RBCs immersed in blood plasma with the surrounding fluid and modeling the deformation of individual cells. The results of numerical simulations are in accordance with the in vivo observed region of interest within the caudal vein plexus of the zebrafish embryo. Good agreement of results demonstrates the capabilities of the developed numerical model to predict and analyze the motion and deformation of RBCs in complex geometries. The proposed model (methodology) will help to elucidate different rheological and hematological related pathologies and finally to design better treatment strategies.

  14. Systolic-diastolic functional coupling in healthy children and in those with dilated cardiomyopathy.

    Science.gov (United States)

    Friedberg, Mark K; Margossian, Renee; Lu, Minmin; Mercer-Rosa, Laura; Henderson, Heather T; Nutting, Arni; Friedman, Kevin; Molina, Kimberly M; Altmann, Karen; Canter, Charles; Sleeper, Lynn A; Colan, Steven D

    2016-06-01

    Systolic and diastolic function affect dilated cardiomyopathy (DCM) outcomes. However, systolic-diastolic coupling, as a distinct characteristic, may itself affect function but is poorly characterized. We hypothesized that echocardiographic left ventricular (LV) longitudinal systolic tissue velocities (S') correlate with diastolic longitudinal velocities (E') and that their relationship is associated with ventricular function and that this relationship is impaired in pediatric DCM. We analyzed data from the Pediatric Heart Network Ventricular Volume Variability study, using linear regression and generalized additive modeling to assess relationships between S' and E' at the lateral and septal mitral annulus. We explored relationships between the systolic:diastolic (S:D) coupling ratio (S':E' relative to age) and ventricular function. Up to 4 echocardiograms from 130 DCM patients (mean age: 9.3 ± 6.1 yr) and 1 echocardiogram from each of 591 healthy controls were analyzed. S' and E' were linearly related in controls (r = 0.64, P < 0.001) and DCM (r = 0.83, P < 0.001). In DCM, the magnitude of association between S' and E' was reduced with progressive ventricular remodeling. The S:D ratio was more strongly associated with LV function in controls vs. DCM. The septal S:D ratio was higher (presumed worse) in DCM vs. controls (0.69 ± 0.13 vs. 0.62 ± 0.12, P = 0.001). A higher septal S:D ratio was associated with worse LV dimensions (parameter estimate: 0.0061, P = 0.004), mass (parameter estimate: 0.0074, P = 0.002), ejection fraction (parameter estimate: -0.0303, P = 0.024), and inflow propagation (parameter estimate: -0.3538, P < .001). S:D coupling becomes weaker in DCM with LV remodeling and dysfunction. The S:D coupling ratio may be useful to assess coupling, warranting study in relation to patient outcomes. Copyright © 2016 the American Physiological Society.

  15. Modeling the cardiovascular system using a nonlinear additive autoregressive model with exogenous input

    Science.gov (United States)

    Riedl, M.; Suhrbier, A.; Malberg, H.; Penzel, T.; Bretthauer, G.; Kurths, J.; Wessel, N.

    2008-07-01

    The parameters of heart rate variability and blood pressure variability have proved to be useful analytical tools in cardiovascular physics and medicine. Model-based analysis of these variabilities additionally leads to new prognostic information about mechanisms behind regulations in the cardiovascular system. In this paper, we analyze the complex interaction between heart rate, systolic blood pressure, and respiration by nonparametric fitted nonlinear additive autoregressive models with external inputs. Therefore, we consider measurements of healthy persons and patients suffering from obstructive sleep apnea syndrome (OSAS), with and without hypertension. It is shown that the proposed nonlinear models are capable of describing short-term fluctuations in heart rate as well as systolic blood pressure significantly better than similar linear ones, which confirms the assumption of nonlinear controlled heart rate and blood pressure. Furthermore, the comparison of the nonlinear and linear approaches reveals that the heart rate and blood pressure variability in healthy subjects is caused by a higher level of noise as well as nonlinearity than in patients suffering from OSAS. The residue analysis points at a further source of heart rate and blood pressure variability in healthy subjects, in addition to heart rate, systolic blood pressure, and respiration. Comparison of the nonlinear models within and among the different groups of subjects suggests the ability to discriminate the cohorts that could lead to a stratification of hypertension risk in OSAS patients.

  16. A Fourier series approach for comparing groups of subjects on ambulatory blood pressure patterns.

    Science.gov (United States)

    Somes, G W; Harshfield, G A; Arheart, K L; Miller, S T

    1994-06-30

    We develop an approach to the statistical analysis of 24-hour ambulatory blood pressure monitoring where we represent each subject's profile by a different mathematical model. We first smooth the data and then use a Fourier series approach to determine the best model for each subject. We then estimate summary variables based on each subject's model to compare distinct groups of subjects. In comparing 15 adult black male hypertensives to eight adult black male normotensives we found that the two groups differ on the shift away from the mesor for both the systolic and the diastolic blood pressure profile.

  17. 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.

  18. Dragon's blood dropping pills have protective effects on focal cerebral ischemia rats model.

    Science.gov (United States)

    Xin, Nian; Yang, Fang-Ju; Li, Yan; Li, Yu-Juan; Dai, Rong-Ji; Meng, Wei-Wei; Chen, Yan; Deng, Yu-Lin

    2013-12-15

    Dragon's blood is a bright red resin obtained from Dracaena cochinchinensis (Lour.) S.C.Chen (Yunnan, China). As a traditional Chinese medicinal herb, it has great traditional medicinal value and is used for wound healing and to stop bleeding. Its main biological activity comes from phenolic compounds. In this study, phenolic compounds were made into dropping pills and their protective effects were examined by establishing focal cerebral ischemia rats model used method of Middle Cerebral Artery Occlusion (MCAO), and by investigating indexes of neurological scores, infarct volume, cerebral index, cerebral water content and oxidation stress. Compared to model group, high, middle and low groups of Dragon's blood dropping pills could improve the neurological function significantly (pDragon's blood dropping pills had protective effects on focal cerebral ischemia rats.

  19. Mathematical Models and Numerical Simulations for the Blood Flow in Large Vessels

    Directory of Open Access Journals (Sweden)

    Titus PETRILA

    2012-12-01

    Full Text Available We are proposing a non-Newtonian, Cross type rheological model for the blood flow, under the conditions of an unsteady flow regime connected with the rhythmic pumping of the blood by the heart. We admit the incompressibility and homogeneity of the blood while its flow is laminar and the exterior body forces are neglected. We take also into account the viscoelastic behavior of the vessel walls. The mathematical equations and the appropriate boundary conditions are considered in cylindrical (axisymmetric coordinates. Numerical experiments in case of stenosed artery and in artery with aneurysm (using COMSOL Multiphysics 3.3 are made. The variation of the wall shear stress, which is believed to have a special importance in the rupture of aneurysms, is calculated using both a Newtonian and a non-Newtonian model.

  20. Flow of a blood analogue fluid in a compliant abdominal aortic aneurysm model: experimental modelling.

    Science.gov (United States)

    Deplano, Valérie; Knapp, Yannick; Bailly, Lucie; Bertrand, Eric

    2014-04-11

    The aim of this work is to develop a unique in vitro set-up in order to analyse the influence of the shear thinning fluid-properties on the flow dynamics within the bulge of an abdominal aortic aneurysm (AAA). From an experimental point of view, the goals are to elaborate an analogue shear thinning fluid mimicking the macroscopic blood behaviour, to characterise its rheology at low shear rates and to propose an experimental device able to manage such an analogue fluid without altering its feature while reproducing physiological flow rate and pressure, through compliant AAA. Once these experimental prerequisites achieved, the results obtained in the present work show that the flow dynamics is highly dependent on the fluid rheology. The main results point out that the propagation of the vortex ring, generated in the AAA bulge, is slower for shear thinning fluids inducing a smaller travelled distance by the vortex ring so that it never impacts the anterior wall in the distal region, in opposition to Newtonian fluids. Moreover, scalar shear rate values are globally lower for shear thinning fluids inducing higher maximum stress values than those for the Newtonian fluids. Consequently, this work highlights that a Newtonian fluid model is finally inadequate to obtain a reliable prediction of the flow dynamics within AAA.

  1. [Atrial filling fraction predicts left ventricular systolic function after myocardial infarction: pre-discharge echocardiographic evaluation].

    Science.gov (United States)

    Galderisi, M; Fakher, A; Petrocelli, A; Alfieri, A; Garofalo, M; de Divitiis, O

    1995-10-01

    Aim of the study was to examine the relation between Doppler-derived indices of left ventricular diastolic and systolic function early after myocardial infarction. Fifty-three patients (31 males, 22 females) recovering from acute myocardial infarction underwent predischarge Doppler echocardiographic examination. Patients with age > 70 years, previous myocardial infarction, more than mild mitral and aortic regurgitation, mitral and aortic stenosis were excluded. Twenty-two healthy subjects (13 males; 9 females) free of coronary risk factors were selected as the control group. Both end-diastolic and end-systolic volumes and ejection fraction were measured by two-dimensional echocardiography. Pulsed Doppler was used to evaluate mitral inflow and left ventricular outflow velocity patterns. The following indices were measured: peak velocity of early (E) and late (A) flows, ratio of E/A peak velocities, ratio of early to late time velocity integrals, atrial filling fraction (time velocity integral A / time velocity integral of flow during total diastole) and deceleration time of E wave for mitral inflow; peak and time-velocity integral for left ventricular outflow. Stroke volume and cardiac output were obtained by pulsed Doppler using the left ventricular outflow method. The two groups were comparable for age, with blood pressure (p volumes were significantly higher (both p volume and cardiac output (both p volumes, atrial filling fraction was an independent predictor of stroke volume, with a direct relation (beta coefficient = 0.53, p volume indicates the importance of atrial contribution to maintain an adequate systolic performance in patients with myocardial infarction.

  2. Blood transcriptomic markers for major depression: from animal models to clinical settings.

    Science.gov (United States)

    Redei, Eva E; Mehta, Neha S

    2015-05-01

    Depression is a heterogeneous disorder and, similar to other spectrum disorders, its manifestation varies by age of onset, severity, comorbidity, treatment responsiveness, and other factors. A laboratory blood test based on specific biomarkers for major depressive disorder (MDD) and its subgroups could increase diagnostic accuracy and expedite the initiation of treatment. We identified candidate blood biomarkers by examining genome-wide expression differences in the blood of animal models representing both the genetic and environmental/stress etiologies of depression. Human orthologs of the resulting transcript panel were tested in pilot studies. Transcript abundance of 11 blood markers differentiated adolescent subjects with early-onset MDD from adolescents with no disorder (ND). A set of partly overlapping transcripts distinguished adolescent patients who had comorbid anxiety disorders from those with only MDD. In adults, blood levels of nine transcripts discerned subjects with MDD from ND controls. Even though cognitive behavioral therapy (CBT) resulted in remission of some patients, the levels of three transcripts consistently signaled prior MDD status. A coexpression network of transcripts seems to predict responsiveness to CBT. Thus, our approach can be developed into clinically valid diagnostic panels of blood transcripts for different manifestations of MDD, potentially reducing diagnostic heterogeneity and advancing individualized treatment strategies.

  3. Fluid-structure Interaction Modeling of Aneurysmal Conditions with High and Normal Blood Pressures

    Science.gov (United States)

    Torii, Ryo; Oshima, Marie; Kobayashi, Toshio; Takagi, Kiyoshi; Tezduyar, Tayfun E.

    2006-09-01

    Hemodynamic factors like the wall shear stress play an important role in cardiovascular diseases. To investigate the influence of hemodynamic factors in blood vessels, the authors have developed a numerical fluid-structure interaction (FSI) analysis technique. The objective is to use numerical simulation as an effective tool to predict phenomena in a living human body. We applied the technique to a patient-specific arterial model, and with that we showed the effect of wall deformation on the WSS distribution. In this paper, we compute the interaction between the blood flow and the arterial wall for a patient-specific cerebral aneurysm with various hemodynamic conditions, such as hypertension. We particularly focus on the effects of hypertensive blood pressure on the interaction and the WSS, because hypertension is reported to be a risk factor in rupture of aneurysms. We also aim to show the possibility of FSI computations with hemodynamic conditions representing those risk factors in cardiovascular disease. The simulations show that the transient behavior of the interaction under hypertensive blood pressure is significantly different from the interaction under normal blood pressure. The transient behavior of the blood-flow velocity, and the resulting WSS and the mechanical stress in the aneurysmal wall, are significantly affected by hypertension. The results imply that hypertension affects the growth of an aneurysm and the damage in arterial tissues.

  4. Low-level lead exposure and elevations in blood pressure during pregnancy.

    Science.gov (United States)

    Wells, Ellen M; Navas-Acien, Ana; Herbstman, Julie B; Apelberg, Benjamin J; Silbergeld, Ellen K; Caldwell, Kathleen L; Jones, Robert L; Halden, Rolf U; Witter, Frank R; Goldman, Lynn R

    2011-05-01

    Lead exposure is associated with elevated blood pressure during pregnancy; however, the magnitude of this relationship at low exposure levels is unclear. Our goal was to determine the association between low-level lead exposure and blood pressure during late pregnancy. We collected admission and maximum (based on systolic) blood pressures during labor and delivery among 285 women in Baltimore, Maryland. We measured umbilical cord blood lead using inductively coupled plasma mass spectrometry. Multivariable models were adjusted for age, race, median household income, parity, smoking during pregnancy, prepregnancy body mass index, and anemia. These models were used to calculate benchmark dose values. Geometric mean cord blood lead was 0.66 μg/dL (95% confidence interval, 0.61-0.70). Comparing blood pressure measurements between those in the highest and those in the lowest quartile of lead exposure, we observed a 6.87-mmHg (1.51-12.21 mmHg) increase in admission systolic blood pressure and a 4.40-mmHg (0.21-8.59 mmHg) increase in admission diastolic blood pressure after adjustment for confounders. Corresponding values for maximum blood pressure increase were 7.72 (1.83-13.60) and 8.33 (1.14-15.53) mmHg. Benchmark dose lower limit values for a 1-SD increase in blood pressure were blood lead for all blood pressure end points. A significant association between low-level lead exposures and elevations in maternal blood pressure during labor and delivery can be observed at umbilical blood lead levels < 2 μg/dL.

  5. Prevalence of impaired left ventricular systolic function and heart failure in a middle-aged and elderly urban population segment of Copenhagen

    DEFF Research Database (Denmark)

    Raymond, I.; Pedersen, F.; Steensgaard-Hansen, F.

    2003-01-01

    OBJECTIVE: To assess the prevalence of impaired left ventricular systolic function and manifest heart failure in a general population aged 50-89 years. DESIGN: In this cross sectional survey, participants filled in a heart failure questionnaire. ECG, blood tests, and echocardiography were performed...

  6. The development of a recruiting-drawing-inventory model for a community blood bank system.

    Science.gov (United States)

    Smackey, B M

    1975-01-01

    A community blood bank system is a multiorganizational program that is designed to supply the blood needs of a community. Participating in such a program are hospitals, a central blood bank, industrial donor groups, the American Red Cross, advisory committees, and the community at large. The underlying determinant of the community's success or failure with its blood program is the degree of cooperation among the various organizations. Intertwined with organizational considerations are the management problems associated with the operation of a responsive and efficient inventory control system. This paper reports on the development of a system for a community blood bank that is in its third year of operation. The system that has been developed can be operated manually by a part-time clerk. Details of the model include an integration of the donor scheduling function and the inventory control function. Simulated testing of the model has been conducted and full-scale implementation is awaiting the expansion of the known donor base.

  7. An immersed-boundary method for modeling flow of deformable blood cells in complex geometry

    Science.gov (United States)

    Balogh, Peter; Bagchi, Prosenjit

    2016-11-01

    We present a computational methodology for simulating blood flow at the cellular scale in highly complex geometries, such as microvascular networks. Immersed boundary methods provide the foundation for our approach, as they allow modeling flows in arbitrary geometries, in addition to resolving the large deformation and dynamics of individual blood cell with high fidelity. Different simulation components are seamlessly integrated into the present methodology that can simultaneously model stationary rigid boundaries of arbitrary and complex shape, moving rigid bodies, and highly deformable interfaces of blood cells that are governed by non-linear elasticity. This permits physiologically realistic simulations of blood cells flowing in complex microvascular networks characterized by multiple bifurcating and merging vessels. The methodology is validated against analytical theory, experimental data, and previous numerical results. We then demonstrate the capabilities of the methodology by simulating deformable blood cells and heterogeneous cell suspensions flowing in both physiologically realistic microvascular networks and geometrically intricate microfluidic devices. The methodology offers the potential of scaling up to large microvascular networks at organ levels. Funded by NSF CBET 1604308.

  8. Magnetic resonance imaging of cerebral blood flow in animal stroke models

    Directory of Open Access Journals (Sweden)

    Qiang Shen

    2016-01-01

    Full Text Available Perfusion could provide useful information on the metabolic status and functional status of tissues and organs. This review summarizes the most commonly used perfusion measurement methods: Dynamic susceptibility contrast (DSC and arterial spin labeling (ASL and their applications in experimental stroke. Some new developments of cerebral blood flow (CBF techniques in animal models are also discussed.

  9. Magnetic Resonance Imaging of Cerebral Blood Flow in Animal Stroke Models

    OpenAIRE

    Qiang Shen; Timothy Q Duong

    2016-01-01

    Perfusion could provide useful information on the metabolic status and functional status of tissues and organs. This review summarizes the most commonly used perfusion measurement methods: Dynamic susceptibility contrast (DSC) and arterial spin labeling (ASL) and their applications in experimental stroke. Some new developments of cerebral blood flow (CBF) techniques in animal models are also discussed.

  10. Deriving a blood-mimicking fluid for particle image velocimetry in Sylgard-184 vascular models.

    Science.gov (United States)

    Yousif, Majid Y; Holdsworth, David W; Poepping, Tamie L

    2009-01-01

    A new blood-mimicking fluid (BMF) has been developed for particle image velocimetry (PIV), which enables flow studies in vascular models (phantoms). A major difficulty in PIV that affects measurement accuracy is the refraction and distortion of light passing through the interface between the model and the fluid, due to the difference in refractive index (n) between the two materials. The problem can be eliminated by using a fluid with a refractive index matching that of the model. Such fluids are not commonly available, especially for vascular research where the fluid should also have a viscosity similar to human blood. In this work, a blood-mimicking fluid, composed of water (47.38% by weight), glycerol (36.94% by weight) and sodium iodide salt (15.68% by weight), was developed for compatibility with our silicone (Sylgard 184; n = 1.414) phantoms. The fluid exhibits a dynamic viscosity of 4.31+/-0.03 cP which lies within the range of human blood viscosity (4.4+/-0.6 cP). Both refractive index and viscosity were attained at 22.2+/-0.2 degrees C, which is a feasible room temperature, thus eliminating the need for a temperature-control system. The fluid will be used to study hemodynamics in vascular flow models fabricated from Sylgard 184.

  11. In vitro models of the blood-brain barrier

    DEFF Research Database (Denmark)

    Helms, Hans Christian Cederberg; Abbott, N Joan; Burek, Malgorzata

    2016-01-01

    components of plasma and xenobiotics. This "blood-brain barrier" function is a major hindrance for drug uptake into the brain parenchyma. Cell culture models, based on either primary cells or immortalized brain endothelial cell lines, have been developed, in order to facilitate in vitro studies of drug...

  12. Lake Baikal Endemic Sculpins (Cottoidei: A Promising Model to Study Adaptive Plasticity of Blood Cholesterol Metabolism

    Directory of Open Access Journals (Sweden)

    Nikolay P. Sudakov

    2015-08-01

    Full Text Available We analyzed the blood lipid spectra in four closely related sculpin (Cottoidei species endemic to Lake Baikal. These data characterize the Baikal sculpins as a set of model organisms for studying the adaptive plasticity of cholesterol metabolism and also mechanisms of resistance to the development of dyslipidemia and atherosclerosis.

  13. The Solution of Modified Fractional Bergman’s Minimal Blood Glucose-Insulin Model

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    Badr S. Alkahtani

    2017-05-01

    Full Text Available In the present paper, we use analytical techniques to solve fractional nonlinear differential equations systems that arise in Bergman’s minimal model, used to describe blood glucose and insulin metabolism, after intravenous tolerance testing. We also discuss the stability and uniqueness of the solution.

  14. Modeling of Shear-Induced Red Blood Cell Migration for Guiding Microfluidic Device Design

    Science.gov (United States)

    Durant, Eden; Higgins, Adam; Sharp, Kendra

    2014-11-01

    Through refinement and extension of a two-phase flow model previously reported for modeling blood in cylindrical flows (Gidaspow, 2009), we have developed a computational model for blood flow in complex microfluidic. Treating plasma as a Newtonian fluid and the Red Blood Cells (RBCs) as a granular phase, whose local concentrations are determined statistically, we have captured the migration of RBCs and concomitant formation of a cell free plasma layer at the channel walls. This model provides us with a three-dimensional distribution of RBCs and the development of the stead-state flow profile, and enables us to study the influence of complex microfluidic geometries, including flow obstacles and varying channel dimensions, on the rate and extent of RBC margination. Simulations on 50 and 100 micron square channels match observed trends including decreasing RBC margination rate in larger channels, increasing RBC margination rate with higher hematocrit, and decreasing cell free layer width with increasing hematocrit. This predictive capability will allow microfluidic devices to be tailored and optimized for specific biomedical applications such as separation of blood constituents.

  15. LASER-DOPPLER VELOCIMETRY AND MONTE-CARLO SIMULATIONS ON MODELS FOR BLOOD PERFUSION IN TISSUE

    NARCIS (Netherlands)

    DEMUL, FFM; KOELINK, MH; KOK, ML; HARMSMA, PJ; GREVE, J; GRAAFF, R; AARNOUDSE, JG

    1995-01-01

    Laser Doppler flow measurements and Monte Carlo simulations on small blood perfusion flow models at 780 nm are presented and compared. The dimensions of the optical sample volume are investigated as functions of the distance of the laser to the detector and as functions of the angle of penetration o