Search Results (126)

Background/Objectives: Patients with chronic kidney disease (CKD) often present with peripheral arterial stiffness (PAS), which is associated with an increased cardiovascular risk. This study assessed the association between circulating osteoprotegerin (OPG), a known mediator of vascular calcification, and PAS, measured as brachial–ankle pulse wave velocity (baPWV), in patients with CKD. Methods: This cross-sectional investigation engaged 200 individuals with non-dialysis CKD. Serum OPG concentrations were measured using a commercial enzyme-linked immunosorbent assay. Participants were classified as having PAS when either left or right baPWV was greater than 18.0 m/s; those with baPWV values of 18.0 m/s or lower were assigned to the control group. Results: Eighty-six patients (43.0%) had PAS. In comparison to controls, PAS patients were older (p < 0.001) and had higher proportions of diabetes mellitus (p = 0.023) and hypertension (p = 0.010); systolic blood pressure was higher (p < 0.001), urine protein-to-creatinine ratio was elevated (p = 0.004), and serum OPG was markedly greater (p < 0.001), whereas estimated glomerular filtration rate was lower (p = 0.003). After full adjustment, OPG levels, in addition to older age and diabetes mellitus, demonstrated an independent association with PAS (odds ratio: 1.008; 95% confidence interval: 1.002–1.015; p = 0.010). The OPG level was positively associated with bilateral baPWV by Spearman’s correlation analysis (p < 0.001). Conclusions: Circulating OPG level showed an independent association with PAS and baPWV in CKD patients not yet on dialysis. Hence, OPG can be a potential marker of vascular risk in this patient population. Full article

Accurate acoustic emission (AE) source localization in complex structures remains challenging due to non-straight wave propagation paths and the difficulty of obtaining reliable wave velocity models. To address these issues, this study proposes a velocity-free AE source localization method based on an any-angle pathfinding algorithm. The method integrates the Anya algorithm to estimate geometrically optimal propagation paths and a velocity-free objective function formulated under a weak anisotropy assumption. By avoiding the directional limitations of conventional grid-based pathfinding, the proposed approach provides more accurate distance estimates between potential sources and sensors without requiring prior velocity information. The effectiveness of the method was validated through an AE pulse experiment conducted on a granite specimen containing multiple cylindrical holes. The results demonstrate that the average location error of the proposed method is 19.02 mm, which is less than 38.14 mm of the traditional method and 22.90 mm of the velocity-free method using a grid-based search algorithm. Therefore, the proposed framework is applicable to two-dimensional structures or extruded three-dimensional structures, offering a feasible approach for AE source localization in complex environments. Full article

Background: Arterial stiffness (AS) is a key marker of vascular aging and an independent predictor of cardiovascular risk. Although diet has been proposed as an important modifiable factor influencing vascular health, the independent associations between specific macronutrients and minerals and the progression of arterial stiffness remain insufficiently characterized. Objective: The aim of this longitudinal study was to evaluate the independent associations of baseline dietary macronutrient and mineral intake with the 5-year progression of arterial stiffness (assessed via carotid–femoral pulse wave velocity (cfPWV) and cardio-ankle vascular index (CAVI) in adults without prior cardiovascular disease. Methods: This longitudinal study included 466 participants from the EVA study who were evaluated at baseline and after a five-year follow-up (mean age 55.96 ± 14.15 years; 51.1% women). Arterial stiffness was assessed using cfPWV and CAVI. Dietary intake of macronutrients and minerals was estimated using the EVIDENT smartphone application. Multivariable linear regression models were used to examine the association between nutrient intake and arterial stiffness progression. Model 1 was adjusted for age and sex, and Model 2 was additionally adjusted for lifestyle variables and cardiovascular risk factors. Dietary intake was exclusively documented at baseline using a 3-day dietary record, while arterial stiffness parameters (cfPWV and CAVI) were assessed both at baseline and at the five-year follow-up. Results: Higher dietary fiber intake was independently associated with a lower increment in cfPWV after full adjustment (β = −0.025; 95% CI (confidence interval): −0.046 to −0.005). Alcohol intake showed a positive association with CAVI increment in the fully adjusted model (β = 0.020; 95% CI: 0.006 to 0.034). Iron intake was also independently associated with increased CAVI (β = 0.022; 95% CI: 0.004 to 0.041). Carbohydrate intake showed a small positive association with CAVI, whereas no consistent independent associations were observed for other macronutrients or minerals. Conclusions: In this adult population without previous cardiovascular disease, higher dietary fiber intake was associated with lower progression of central arterial stiffness, whereas alcohol and iron intake showed positive associations with peripheral arterial stiffness. Overall, most nutrients were not independently related to arterial stiffness after comprehensive adjustment. These findings suggest that selected dietary components may contribute modestly to vascular aging. Full article

Background: Stretching exercises are strongly recommended as part of exercise training programs; however, their effects on blood pressure (BP) and other related cardiovascular parameters in adult individuals with elevated BP (pre-hypertension) or hypertension remain unclear. Methods: A systematic search was conducted in PubMed and databases accessed via the EBSCO platform up to 30 September 2025, following the PRISMA guidelines. An additional search of Scopus was performed on 8 April 2026. Studies eligible for inclusion were randomized controlled trials, randomized crossover trials, non-randomized clinical trials and single-arm trials investigating stretching interventions in adults with pre-hypertension and or hypertension. Risk of bias assessment was performed using RoB 2 for randomized trials and ROBINS-I for the non-randomized trials. A random-effect meta-analysis was performed when at least two studies reported sufficiently comparable BP outcomes. The quantitative synthesis was considered exploratory. Results: Eleven records published between 2014 and 2025 met the eligibility criteria and were included. All protocols used static stretching, although only a small number were clearly described as active stretching. The results were heterogeneous across the design, duration of intervention and outcomes. Chronic interventions more often reported favorable changes in indices of arterial stiffness, whereas acute interventions demonstrated more variable immediate BP responses. In the exploratory meta-analysis, the pooled estimate suggested a reduction in systolic blood pressure (SBP) in favor of stretching; however, this effect did not reach statistical significance (mean difference (MD) = −5.39 mmHg, 95% confidence interval (CI): −11.32 to 0.53; I² = 0%). For diastolic blood pressure (DBP), the pooled estimate favored stretching and reached statistical significance (MD = −3.93 mmHg, 95% CI: −7.25 to −0.60; I² = 0%). In sensitivity analyses including a third study, the pooled effects remained in favor of stretching for systolic BP (MD = −6.6 mmHg, 95% CI: −12.2 to −1.0; I² = 56%) and diastolic BP (MD = −5.4 mmHg, 95% CI: −7.1 to −3.7; I² = 8%). These pooled estimates should be interpreted with caution due to the small number of studies, heterogeneity in study design and participant characteristics, and overall limitations in methodological quality. Secondary findings suggested possible improvements in selected vascular parameters, including brachial–ankle pulse wave velocity, augmentation index, and cardio–ankle vascular index, whereas acute responses were more variable and protocol-dependent. Overall, the level of evidence was limited, with most randomized trials judged as having some concerns and non-randomized studies judged as having a critical risk of bias. Conclusions: Stretching interventions may improve BP and selected vascular parameters in adults with pre-hypertension and hypertension and may represent a practical adjunct within the non-pharmacological management of BP. However, the current evidence is limited by methodological heterogeneity, risk of bias, and the small number of studies available for quantitative synthesis. Therefore, the pooled findings should be considered exploratory and hypothesis-generating rather than definitive. Further high-quality randomized controlled trials are required to determine the optimal type, dose, and long-term clinical relevance of stretching interventions in this population. Full article

Background: Early vascular aging (EVA) is a common complication of type 2 diabetes mellitus. Early identification is crucial in middle-aged individuals with T2DM, as vascular stiffness can occur gradually for years before cardiovascular disease. However, EVA is rarely considered in routine care. Adropin is a vasoprotective peptide that may counter-regulate endothelin-1 (ET-1). Therefore, this study aims to examine the association between circulating adropin, ET-1, oxLDL, MMP-2, VEGFA, and EVA. Methods: This observational study included 300 adults aged 25–55 years (150 T2DM; 150 age/sex-matched controls). ePWV was calculated from age and mean blood pressure. EVA was classified using a residual-based, age-specific ePWV threshold derived from controls. Associations were tested using correlation and logistic regression. ROC and decision curve analyses were performed to evaluate diagnostic performance and clinical utility. Results: EVA prevalence was 38.6% overall, occurring in 7.3% of controls and increasing across T2DM with good and poor glycemic control (56.1% and 80.95%, respectively, p < 0.001). Compared with normal vascular aging, EVA showed lower adropin and higher ET-1, oxLDL and MMP-2, with lower VEGFA (all p < 0.05). In fully adjusted models, adropin (OR 0.991 per pg/mL; p < 0.001) and ET-1 (OR 1.017 per pg/mL, p = 0.005) remained independently associated with EVA. A combined adropin + ET-1 predictor improved discrimination (AUC 0.901, 95% CI 0.868–0.934), at a predicted-probability cutoff of 0.607, 78.7% sensitivity and 87.0% specificity. Conclusions: In middle-aged T2DM, EVA was associated with lower adropin and higher ET-1 in T2DM. These findings support an association between these biomarkers and the EVA phenotype. Full article

Background and Objectives: Sclerostin or dickkopf-1 (DKK1) inhibits the canonical Wnt/β-catenin signaling pathway, which regulates vascular calcification and may contribute to the development of arterial stiffness. The brachial–ankle pulse wave velocity (baPWV) measures peripheral arterial stiffness (PAS). This study aimed to investigate the correlation between sclerostin and DKK1 levels and PAS in patients with type 2 diabetes mellitus (T2DM). Materials and Methods: Biochemical data and sclerostin and DKK1 levels were analyzed in the fasting blood samples of 125 patients with T2DM. baPWV measurements using the VaSera VS-1000 automatic pulse wave analyzer classified patients with values > 18.0 m/s on either side into the PAS group. Results: Among patients with T2DM, 47 (37.6%) were classified as having PAS. These patients exhibited higher hypertension prevalence (p = 0.002); greater age (p < 0.001); elevated systolic (p < 0.001) and diastolic blood (p = 0.012) pressures; and increased fasting glucose (p = 0.001), glycated hemoglobin (p = 0.008), triglyceride (p = 0.001), blood urea nitrogen (p < 0.001), and creatinine (p = 0.001) levels, urine albumin-to-creatinine ratio (p = 0.039), and C-reactive protein (p = 0.024) and serum sclerostin (p < 0.001) levels, but decreased estimated glomerular filtration rate (p < 0.001). Multivariate logistic regression analysis identified serum sclerostin level (odds ratio, 1.127; 95% confidence interval, 1.058–1.200; p < 0.001) as an independent PAS predictor in patients with T2DM. Serum log-transformed sclerostin levels were positively correlated with left (p = 0.005) and right (p = 0.001) baPWV via Spearman’s rank-order correlation coefficient analysis. Conclusions: Serum sclerostin levels, but not DKK1 levels, are positively correlated with PAS in patients with T2DM. Full article

Background: Severe aortic stenosis (AS) increases left ventricular afterload and disrupts ventricular–vascular coupling. Transcatheter aortic valve replacement (TAVR) promptly relieves valvular obstruction, but its immediate effects on blood pressure-dependent arterial load and ventricular–vascular interactions are not fully clarified. Estimated pulse wave velocity (ePWV), derived from age and mean arterial pressure, is a convenient surrogate of global arterial load. The study aimed to assess ePWV before and after TAVR and its relationship with ventricular function and inflammatory biomarkers. Methods: In this retrospective observational study, 100 elderly patients with severe AS undergoing TAVR underwent detailed clinical, laboratory, and echocardiographic assessments before and after the procedure. Arterial stiffness was quantified using ePWV, while left ventricular geometry and systolic function were evaluated by standard echocardiography. Post-procedural reassessment was performed at hospital discharge (median 8 days after TAVR). Results: TAVR led to a modest but significant reduction in ePWV (from 12.79 ± 1.54 to 12.39 ± 1.54 m/s, p < 0.01) and improvement in left ventricular ejection fraction (LVEF) (from 44.89 ± 9.2% to 46.7 ± 7.95%, p < 0.01). Higher baseline ePWV correlated with unfavorable left ventricular remodeling and systolic dysfunction, and post-procedural ePWV remained linked to right ventricular performance. Before TAVR, ePWV and LVEF were both associated with inflammatory biomarkers, relationships that disappeared after intervention. Conclusions: Overall, ePWV functioned as an integrated measure of ventricular–vascular interaction and global hemodynamic load, though its interpretation post-TAVR requires caution due to direct blood pressure dependence and confounding by acute procedural inflammation. Full article

Objectives: This study aimed to investigate the associations between serum lipid biomarkers and pulse wave analysis (PWA) variables in patients at high and very high cardiovascular risk, with particular emphasis on age-related differences. Methods: Seventy-six patients at high or very high cardiovascular risk were enrolled and stratified into middle-aged (Group 1) and elderly (Group 2). All participants underwent PWA, and multiple serum lipid biomarkers were measured, including composite lipid indices. Results: In both age groups, PWA parameters showed significant correlations with serum lipid biomarkers. Systolic blood pressure (SBP) was an independent determinant of the lipid balance index (LBI), while pulse wave velocity (PWV) and SBP were independent determinants of the triglyceride–glucose (TyG) index. PWV correlated with age in both groups and was higher in Group 2 for comparable blood pressure values. In middle-aged patients, diastolic blood pressure (DBP) showed significant, independent associations with triglycerides and TyG, indicating a close link between peripheral vascular resistance and metabolic dysfunction in earlier stages of cardiovascular risk. In elderly patients, SBP and pulse pressure were predominantly associated with lipid-derived indices, reflecting the increasing contribution of large-artery stiffness and lipid-driven vascular remodeling with advancing age. Systematic Coronary Risk Estimation 2 (SCORE2) correlated significantly with PWV, the lipid index (LI), and the LBI. Conclusions: Serum lipid biomarkers and PWA-derived hemodynamic variables exhibit a significant, age-dependent interplay in patients with high and very high cardiovascular risk. These findings underscore the importance of age-specific evaluation of lipid–hemodynamic interactions to improve early identification and targeted management of high-risk individuals. Full article

Ultrasonic testing is a prevalent method for non-destructive evaluation of railway rails; however, conventional Time-of-Flight (ToF) approaches applied in practical dry-coupled inspections often rely on simplified assumptions regarding wave propagation velocity and neglect complex waveform characteristics. This paper presents a robust depth estimation framework for surface-breaking cracks that enhances sizing accuracy through effective velocity calibration and Hilbert envelope extraction. Unlike standard methods that assume the free-space speed of sound in air (343 m/s) for wave propagation within the air-filled gap of a surface-breaking crack, we propose an effective velocity model derived from in situ calibration to account for the boundary layer viscosity and thermal conduction effects within narrow crack geometries. The signal processing chain incorporates spectral analysis, band-pass filtering, and Hilbert Transform-based envelope detection to mitigate noise and resolve phase ambiguities. Experimental validation on steel specimens with controlled defects (0.2–10.0 mm) demonstrates that the proposed method achieves an exceptional linear correlation (R² ≈ 0.9976). The calibrated effective velocity was determined to be 289.3 m/s, approximately 15.6% lower than the speed of sound in air, confirming the significant influence of confinement effects. Furthermore, excitation parameters were optimized, identifying that high-voltage excitation (≥110 V) and a tuned pulse width (≈150 ns) are critical for maximizing the signal-to-noise ratio. The results confirm that combining physical model calibration with advanced signal analysis significantly reduces systematic errors, paving the way for portable, high-precision rail inspection systems. Full article

Introduction: Metabolic acidosis is common after kidney transplantation and is associated with adverse outcomes. However, its vascular and functional correlates in kidney transplant recipients remain insufficiently characterized. Methods: We conducted a cross-sectional study of adult kidney transplant recipients attending routine outpatient visits at a tertiary transplant center. Metabolic acidosis was defined as serum bicarbonate < 22 mmol/L. Arterial stiffness was assessed by carotid–femoral pulse wave velocity (PWV), and physical frailty was evaluated using the Fried frailty phenotype. Multivariable regression models were used to identify determinants of metabolic acidosis and to examine its association with arterial stiffness and frailty severity. Results: Among 239 patients (median age 46 years), 154 (64%) had metabolic acidosis. Lower estimated glomerular filtration rate and higher systemic inflammation were independently associated with metabolic acidosis. Metabolic acidosis was independently associated with higher arterial stiffness, with a 1.41 m/s higher PWV after adjustment for age, sex, blood pressure, kidney function, and diabetes mellitus (p < 0.001). Although metabolic acidosis was associated with greater frailty severity in minimally adjusted models, this association was attenuated and no longer statistically significant after further adjustment for kidney function, diabetes, and inflammation. In stable kidney transplant recipients, metabolic acidosis is independently associated with increased arterial stiffness but not with frailty after accounting for key clinical confounders. Conclusions: These findings highlight metabolic acidosis as a marker of vascular vulnerability and a potential therapeutic target after kidney transplantation. Full article

Background: Evidence from prospective studies on the relationship of the dietary vitamin intake and the progression of central and peripheral arterial stiffness remains limited. Objective: To evaluate the association between dietary vitamin intake with the changes in central and peripheral arterial stiffness over a five-year follow-up in adults without previous cardiovascular disease. Methods: This five-year longitudinal study included 466 participants from the EVA study who were evaluated at baseline and follow-up (mean age 55.96 ± 14.15 years; 51.1% women). Central arterial stiffness was assessed using carotid–femoral pulse wave velocity (cfPWV), and peripheral arterial stiffness was measured using brachial–ankle pulse wave velocity (baPWV). Dietary vitamin intake was estimated using the EVIDENT smartphone application, developed and validated by CGB and the Salamanca Primary Care (APISAL; registration number 00/2014/2207). Results: In multivariable linear regression analyses adjusted for age, sex, lifestyle factors, and cardiovascular risk factors, greater increases in cfPWV were inversely associated with vitamin B9 (folate) intake (β = −0.233; 95% CI: −0.390 to −0.075) and vitamin C intake (β = −0.291; 95% CI: −0.507 to −0.075). Similarly, increases in baPWV were inversely associated with vitamin B9 intake (β = −0.156; 95% CI: −0.287 to −0.025) and vitamin C intake (β = −0.223; 95%CI: −0.402 to −0.044). Conclusions: The progression of central and peripheral arterial stiffness over five years was greater in individuals with lower dietary intakes of vitamin B9 and vitamin C. These findings provide novel evidence supporting the possible role of dietary vitamin intake in the progression of arterial stiffness with aging. Full article

This study evaluates the feasibility of estimating stiffness-related parameters and pulse wave velocity (PWV) in a controlled in vitro circulatory setup using artificial silicone vessels with systematically varied Shore A hardness and wall thickness. From synchronized pressure and capacitive waveforms, fiducial points and engineered features are extracted, together with pump settings (stroke volume and heart rate). A Sugeno-type adaptive neuro-fuzzy inference system (ANFIS) is used for hardness-level prediction and benchmarked against linear regression and contemporary machine-learning/deep-learning baselines using stratified cross-validation. PWV estimates derived via hardness-to-elasticity conversion models and the Moens–Korteweg formulation are evaluated against a reference PWV obtained within the same experimental configuration. Under these controlled conditions, the proposed pipeline shows strong agreement with reference labels and measurements. The results should be interpreted as an in vitro validation step; translation to biological tissues or in vivo data will require external validation, calibration of material-property mapping, and robustness testing under physiological variability and measurement noise. Full article

Pulse-like ground motions can cause severe damage to buried cast iron (CI) pipelines, which necessitates the selection of optimal seismic intensity measures (IMs) to estimate pipeline repair rates. Such a selection is essential for mitigating uncertainty in the seismic risk assessment of buried CI pipelines. For the first time, this study systematically screens the optimal scalar and vector IMs for buried cast iron pipelines with lead-caulked joints under pulse-like ground motions by a symmetrical evaluation based on the criteria of efficiency, sufficiency, and proficiency, providing a new method for reducing uncertainty in pipeline seismic risk assessment. We initiate the study by selecting 124 pulse-like ground motions from the NGA-West2 database and identifying 19 scalar and 171 vector IMs as potential candidates. A two-dimensional soil–pipe model is introduced, incorporating variability in the sealing capacity of lead-caulked joints along the axial direction. CI pipeline repair rates are calculated across various scaling factors and apparent wave velocities, yielding 1116 datasets pertinent to CI pipeline damage. The repair rate is adopted as the engineering demand parameter (EDP) to evaluate the efficiency, sufficiency, and proficiency of candidate IMs. Through comprehensive analysis, peak ground velocity (PGV) and the combination of PGV and the time interval between 5% and 75% of normalized Arias intensity ([PGV, Ds_5–75]) are determined as the optimal scalar- and vector-IMs, respectively, for assessing the repair rate of buried CI pipelines under pulse-like ground motions. Full article

Non-destructive evaluation techniques are increasingly recognised as effective alternatives to destructive testing for estimating the compressive strength of lightweight aggregate concrete (LWAC). Among these, ultrasonic pulse velocity (UPV) is a well-established and widely employed method, characterised by its speed, non-invasiveness, and relative simplicity of implementation. In this study, an experimental dataset comprising 640 core segments from 160 cylindrical specimens, provided for analysis, was investigated. Each segment was described by physical and processing variables or features, including lightweight aggregate (LWA) and concrete densities, casting and vibration times, experimental dry density, and P-wave velocity obtained through UPV testing. A segregation index, derived from UPV measurements and defined as the ratio of local to mean P-wave velocity within each specimen, was also considered, following approaches previously suggested in the literature. A range of machine learning techniques was applied to assess the predictive capacity of local P-wave velocity and segregation index. Most ensemble-based methods and support vector regression (SVR) achieved the highest predictive performance when the segregation index was excluded, suggesting that its inclusion did not improve the predictive ability of the models. By contrast, Gaussian process regression (GPR) showed slight improvements when the segregation index was included. The results confirmed that the P-wave velocity measured by UPV testing is a reliable non-destructive predictor of compressive strength in LWAC. At the same time, the added value of the segregation index remained negligible under conditions of low segregation, as reflected by segregation index values above 0.8. These findings highlight the practical potential of integrating UPV-based measurements with data-driven modelling to enhance the reliability of concrete characterisation and quality control. Full article

Background: Diabetes is associated with sub-optimal vascular function. Current evidence suggested purified anthocyanins (ACNs) could improve cardio-metabolic health, but the dose–response effects on arterial stiffness have not been verified. Objectives: To assess the dose-responsiveness of purified ACNs on vascular stiffness and cardiovascular risk among Chinese middle-aged and elderly patients with either prediabetes or early diabetes. Methods: This was a secondary analysis based on a 12-week double-blind, randomized and placebo-controlled trial. Eligible participants were randomly assigned to placebo, 160, 320 and 640 mg/d ACNs groups (n = 46/group). Information on dietary intakes and lifestyle habits and blood samples were collected at baseline and at week 12. Arterial stiffness and vascular function were measured by brachial-ankle pulse wave velocity (baPWV), ankle-brachial index (ABI) and four-limb blood pressures. Composite cardiovascular indices were estimated based on lipids and anthropometric data. Results: Total 184 eligible participants were recruited and 19 withdrew during the intervention. Baseline characteristics were generally comparable among groups. No significant effects or dose–response relationships were observed by ACNs supplementation on arterial stiffness and cardiovascular risk factors. Conclusions: The 12-week randomized controlled trial among Chinese middle-aged and elderly adults with dysglycemia showed multiple dosages of anthocyanins had no significant impacts on arterial stiffness and cardiovascular risk. Full article