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Background Recent studies have revealed the existence of bone marrow-derived endothelial progenitor cells (EPCs). The number of circulating EPCs might reflect the pathogenesis of atherosclerosis and progression of cardiovascular diseases (CVDs). The purpose of this study was to evaluate the relationship between the number of EPCs and cardiovascular risk factors. Methods Flow cytometry analysis was used to quantify the number of EPCs (CD34+AC133+CD45low) in 135 consecutive hospitalized patients with CVD and 25 healthy subjects. Results The number of EPCs was less in the patients than in the healthy subjects (1,047.4 ± 521.1 vs. 612.8 ± 461.6/ml, P < 0.0001). The number of EPCs significantly correlated with the number of risk factors (r = 0.424, P < 0.0001). The numbers of EPCs in patients with hypertension and diabetes mellitus were less than those in patients without those diseases (762.6 ± 579.5 vs. 495.2 ± 297.7/ml, P < 0.01 and 666.8 ± 505.5 vs. 477.0 ± 290.4/ml, P < 0.05, respectively). In healthy subjects a reduced number of EPCs was found in smokers compared with nonsmokers (833.3 ± 347.5 vs. 1,274.6 ± 560.9/ ml, P < 0.05), whereas smoking did not alter the number of EPCs in the patients group. In multivariate analysis, hypertension and age were independent predictors of reduced number of EPCs. Renin-angiotensin system (RAS) inhibitors increased the number of EPCs (464.7 ± 252.1/ml vs. 617.5 ± 343.5/ml, P < 0.05), while calcium antagonists, diuretics, and ß-blockers did not alter the number of EPCs in patients with hypertension. Conclusions These findings suggest that both aging and hypertension are risk factors for reduced number of EPCs and that RAS inhibitors increase the number of EPCs. [ABSTRACT FROM AUTHOR]

Abstract: A simple method to detect audible echoes is proposed as an objective criterion for room acoustics. This method evaluates the perceptibility of sound reflections that are generated by an impulsive sound source and identifies from reflectograms harmful reflections perceived as echoes. Particularly with this method, the masking effect of reverberation is taken into consideration, which cannot be treated sufficiently by the existing objective criteria. The applicability to room acoustical design is verified by evaluating the impulse responses measured in real halls where audible echoes occurred. It is shown that the proposed method detects audible echoes at an accuracy of more than 90% and would be suitable for practical use. [Copyright &y& Elsevier]

Relations are determined between one of the important subjective attributes of concert hall acoustics, the apparent source width, ASW, and three acoustical measures, interaural cross-correlation coefficient IACCE, LFE, and strength factor G. Although these measures previously have been found to correlate with ASW, their relations with it have not been examined sufficiently, especially in respect to their frequency characteristics. Herein, ASW's are directly determined for electronically reproduced musical sound fields with extensive ranges of values for IACCE and LFE. Investigated as parameters are angles of incidence, the time delay difference between a pair of symmetric early lateral reflections, and the number of early lateral reflections. These studies indicate the relative efficacy of IACCE and LFE for determining ASW under conditions that are realistically encountered in concert halls. The results were compared with measured IACCE's, LFE's, and also the strength factor G's in existing concert halls. It is concluded that the arithmetic average of [1-IACCE]'s at 500, 1 k and 2 k Hz combined with the strength factor Glow of the sound field at frequencies below 250 Hz are physical measures highly correlated with the subjective rank ordering of concert halls and that they cover the effects on ASW of the entire octave-band frequency range from 125 to 4 k Hz. © 1998 Acoustical Society of America. [ABSTRACT FROM AUTHOR]

The dipeptidyl peptidase-4 inhibitor saxagliptin is a widely used antihyperglycemic agent in patients with type 2 diabetes. The purpose of this study was to evaluate the effects of saxagliptin on endothelial function in patients with type 2 diabetes. This was a prospective, multicenter, interventional study. A total of 34 patients with type 2 diabetes were enrolled at four university hospitals in Japan. Treatment of patients was initially started with saxagliptin at a dose of 5 mg daily. Assessment of endothelial function assessed by flow-mediated vasodilation (FMD) and measurement of stromal cell-derived factor-1α (SDF-1α) were conducted at baseline and at 3 months after treatment with saxagliptin. A total of 31 patients with type 2 diabetes were included in the analysis. Saxagliptin significantly increased FMD from 3.1 ± 3.1% to 4.2 ± 2.4% (P = 0.032) and significantly decreased total cholesterol from 190 ± 24 mg/dL to 181 ± 25 mg/dL (P = 0.002), glucose from 160 ± 53 mg/dL to 133 ± 25 mg/dL (P < 0.001), HbA1c from 7.5 ± 0.6% to 7.0 ± 0.6% (P < 0.001), urine albumin-to-creatinine ratio from 63.8 ± 134.2 mg/g to 40.9 ± 83.0 mg/g (P = 0.043), and total SDF-1α from 2108 ± 243 pg/mL to 1284 ± 345 pg/mL (P < 0.001). These findings suggest that saxagliptin is effective for improving endothelial function. [ABSTRACT FROM AUTHOR]

Introduction: Central venous pressure (CVP) is frequently used in clinical practice for the assessment of volume status and cardiac preload for patients with heart failure (HF). The clinical gold standard for evaluating CVP is invasive measurements using right heart catheterization directly via central venous cava, but it is invasive with potential complications. We developed a novel monitoring algorithm termed enclosed zone CVP (ezCVP) for determining static fluid status with use of a conventional noninvasive blood pressure (NIBP). Purpose: The purpose of this study is to validate the relationship between ezCVP and CVP invasively measured by water filled catheter. Methods: 54 patients who underwent right-heart catheterization and measured ezCVP in our hospital were included. Prior to the insertion of Swan-Ganz pulmonary catheter and radial artery sheath, a blood pressure cuff was placed around right upper arm. The NIBP cuff was inflated to 45 mmHg, then the cuff pressure was decreased gradually by 5 mm Hg every 6 seconds to less than 5 mm Hg. The measurement principle for ezCVP is the same as that used for oscillatory arterial blood pressure (ABP) monitoring devices. At mean ABP, cuff pressure oscillation is maximum. In the same way, cuff pressure oscillation derived from CVP is the largest at mean CVP cuff pressure. Cuff pressure oscillation derived from ezCVP overlaps that derived from ABP. Therefore, the envelope of cuff pressure oscillation amplitude has two peaks, with the first observed at a cuff pressure equal to mean ABP and the second observed at a cuff pressure equal to mean CVP defined as ezCVP. Results: Measurements of ezCVP were feasible in 44 patients (Success group, 81.5%) and not feasible in 10 patients due to not obtain oscillatory waveform (Failure group, 18.5%). Between success group and Failure group, there were no difference in clinical characteristics. As invasive hemodynamic assessments, cardiac output measured by Swan-Ganz pulmonary catheter was higher in Success group than in Failure group (p=0.009). The validity of ezCVP was well correlated with that of CVP (R = 0.817, 95%CI 0.775-1.154, p < 0.001). Conclusions: In conclusion, we demonstrated for the first time the feasibility and usefulness of a new noninvasive method, named ezCVP. [ABSTRACT FROM AUTHOR]

Supplemental Digital Content is available in the text. Background: Effort intolerance, measured objectively by reduced peak oxygen consumption (V o2), has been considered as an important prognosticator in degenerative mitral regurgitation (MR). However, its mechanism is unknown. Methods and Results: In 25 asymptomatic/minimally symptomatic patients with grade III+ or greater degenerative MR undergoing semisupine invasive exercise testing, Doppler estimates and invasive measurement of systolic (SPAP) and mean pulmonary artery pressure (MPAP) and cardiac output (CO) were simultaneously obtained. Echocardiographic estimates of SPAP, MPAP, and CO correlated well with invasive measurement at peak exercise (bias, SPAP, −0.7±7.4 mm Hg; MPAP, 1.2±6.3 mm Hg; CO, 0.2±2.5 L/min). Heart rate reserve (β, 3.997; 95% CI, 2.704–5.290 per 41.5% increase; P <0.001), MPAP/CO slope (β, −3.846; 95% CI, −5.926 to −1.766 per 4.85 mm Hg/L per minute increase; P =0.001), and tricuspid annular plane systolic excursion/SPAP slope (β, 4.094; 95% CI, 2.252–5.936 per 0.22 mm/mm Hg increase; P =0.003) were associated with peak V o2 even after adjustment for increase in MR vena contracta during exercise and peak SPAP. The MPAP/CO slope of 4.13 had a sensitivity and a specificity for predicting effort intolerance (%predicted peak V o2 <70%) of 57% and 91%, respectively, whereas the tricuspid annular plane systolic excursion/SPAP slope of 0.25 had a respective sensitivity and specificity of 86% and 82%. Conclusions: The agreement between echocardiographic and invasive measures of pulmonary artery pressures and CO during exercise is acceptable. In patients with degenerative MR, effort intolerance is predominantly because of chronotropic incompetence, abnormal pulmonary vascular reserve, and limited right ventricular contractile reserve and not simply because of exercise-induced MR or pulmonary hypertension. [ABSTRACT FROM AUTHOR]