bluuebunny/crossref_metadata_2025_split huggingface dataset:
5.1 The Role of Blood Pressure, Aortic Stiffness, and Haemodynamics in Brain Health in Older People with Type 2 Diabetes Mellitus
Authors: Karayiannis Christopher , Moran Chris , Beare Richard , Sharman James , Phan Thanh , Thrift Amanda , Wang Wei , Srikanth Velandai 
Published: March 2020

Abstract
Aims
Type 2 diabetes (T2D) is associated with dementia, and abnormal blood pressure (BP), aortic stiffness, and haemodynamics. We aimed to study the contribution of such factors to brain structure and cognition, relative to the contribution of metabolic factors in T2D such as insulin resistance and adiposity, in older people with T2D.

Methods
Cross-sectional sample with T2D in the Cognition and Diabetes in Older Tasmanians–Blood Pressure (CDOT-BP) study. Measurements included neuropsychological battery, brain MRI, and Mobil-o-Graph-derived (IEM, Germany) aortic BP and haemodynamics. We studied associations of exposure variables with outcomes using structural equation modelling for cognition, and simple linear regression for brain structure, using standardised coefficients to determine relative contribution of variables to the outcomes in combined regression models.

Results
202 participants (mean age 68.5 years, mean HbA1c = 6.42%). Augmentation index was associated with processing speed (p < 0.05). The contribution of augmentation index to processing speed (standardized β = −0.237) was greater than waist-hip ratio (β = −0.175) and use of oral glucose lowering medications and insulin (β = −0.126), but less than age (β = −0.431). Peripheral systolic BP, pulse wave velocity, and peripheral nocturnal systolic BP dipping were associated with measures of white matter integrity (fractional anisotropy and mean diffusivity, p < 0.05) but not with cortical thickness.

Conclusion
BP, aortic stiffness and altered haemodynamics contribute to early cognitive change and loss of white matter integrity in T2D. The novel association between nocturnal BP dipping and white matter integrity deserves further investigation. Measuring white matter integrity may be useful to detect the effect of these vascular factors on the brain.
5.2 Arterial Stiffness and Periodontitis: A Systematic Review and Meta-Analysis
Authors: Darnaud Christelle , Courtet Alexandre , Schmitt Audrey , Carra Clotilde , Boutouyrie Pierre , Bouchard Philippe 
Published: March 2020

Abstract
Background
Despite a large number of studies linking cardiovascular diseases and periodontitis (Buhlin et al. 2011; Hansen et al. 2016; Pussinen et al. 2003), few studies make it possible to draw accurate conclusions on the link between periodontitis and arterial stiffness. Endothelial cells maintain vascular homeostasis but are affected by inflammatory injuries (Lacolley et al. 2017). Periodontal diseases involve bacteria-induced inflammation of the tissues supporting the teeth (Tomás et al. 2012), inducing endothelial dysfunction. We conducted a systematic review from existing studies for answering the following questions: (1) Do periodontitis patients have impaired arterial stiffness compared to controls? (2) Is periodontal treatment effective to improve pulse wave velocity (PWV) values?

Methods
A systematic review of the literature, focusing on measurements of PWV in periodontitis patients, was conducted by two independent reviewers. The literature search was done until June 2019. Risk of bias was independently assessed. All clinical studies reporting PWV in patients with severe periodontitis were retrieved for full-text evaluation.

Results
Final selection included 16 studies for qualitative analysis and 10 studies for quantitative analysis (meta-regression analysis). The results show that patients with severe periodontitis have increased PWV compared to controls (PWV mean difference 0.81 m/s; 95% CI: 0.56–1.06; p < 0.00001). This concerns both carotid to femoral, brachial ankle and carotid radial PWV. However, we were unable to identify a positive effect of periodontal treatment on PWV value.

Conclusion
This systematic review and meta-analysis support an association between severe periodontitis and PWV.
5.3 Sex Differences in Blood Pressure in Young Adults: Is It All About Body Size?
Authors: Yu Shikai , McDonnell Barry , Maki-Petaja Kaisa , Cockcroft John , Wilkinson Ian , McEniery Carmel 
Published: March 2020

Abstract
Background
In young adults, systolic blood pressure (SBP) and hypertension rates are significantly lower in females than males, although the extent to which this is due to differences in body size (body surface area; BSA) is unclear. Cardiac output (CO), a key haemodynamic determinant of SBP in young adults, is tightly linked with body size, and typically lower in females. Therefore, we hypothesized that in young adults, CO mediates the association between BSA and SBP, and contributes to sex-related differences in SBP in young adults.

Methods
Complete data were available in 3145 healthy young adults (1558 males, 23 ± 6 years). Linear regression analyses were performed, followed by propensity score matching for BSA to investigate sex-related differences.

Results
BSA was significantly associated with SBP (BSA: β male = 0.337; β female = 0.286; p < 0.001 for both). The regression coefficients did not differ statistically (p = 0.8). Addition of CO to the regression models attenuated, but did not remove these associations (β male = 0.279; β female = 0.234, p < 0.001 for both). Matching males and females for BSA resulted in equivalent values of mean pressure between males and females (83 ± 9 vs 84 ± 12 mmHg, p = 0.8). Despite this sex differences in SBP (121 ± 11 vs 114 ± 13 mmHg), CO (7.8 ± 2.0 vs 6.9 ± 1.5 L/min) and peripheral vascular resistance (PVR, 926 ± 325 vs 1026 ± 275 dynes.sec.cm5) still remained (p < 0.001 for all).

Conclusion
CO partially mediates the association between BSA and SBP in healthy young adults. However, sex differences in SBP and its haemodynamic determinants remain after accounting for differences in body size. In particular, for a given level of body size and mean BP, PVR is disproportionately higher, and CO disproportionately lower, in females, which warrants further investigation.
5.5 A Femoral ‘Stealing’ Effect: Presence of Collateral Retrograde Blood Flow Redistribution in the Femoral Bifurcation During Reactive Hyperemia
Authors: Au Jason , Amelard Robert , Yiu Billy , Nahas Hassan , Hughson Richard , Yu Alfred 
Published: March 2020

Abstract
Background & Purpose
The femoral bifurcation houses complex flow recirculation that may be impacted by downstream peripheral resistance; however, conventional ultrasound is unable to quantify multi-directional flow to study these phenomena. The purpose of this study was to examine the multi-directional behavior of blood in the femoral bifurcation during reactive hyperemia (RH) using vector flow imaging.

Methods
Nine healthy adults (25 ± 4 years; 5 men) underwent high-frame-rate ultrasound imaging of their right femoral bifurcation at rest, and during the first cardiac cycle of RH after 5-min of 200 mmHg calf occlusion. Multi-angle Doppler ultrasound was used to qualitatively describe vector blood flow at 750 fps [1]. The bifurcation region was isolated for blood vector dispersion analysis, an index of flow directionality [2].

Results
Blood flow during RH was characterized by near-constant anterograde blood flow to the superficial femoral artery (SFA), adjacent to low/oscillatory flow immediately proximal to the deep femoral artery (DFA) (Figure 1). We observed collateral blood flow redistribution in 3/9 participants, where blood from the DFA appeared to re-enter the SFA during the retrograde flow period. Bifurcation vector dispersion was reduced from baseline (0.53 ± 0.08 vs 0.67 ± 0.09; p < 0.01), but not eliminated, due to preservation of DFA flow reversal.

Conclusion
We demonstrate the presence of distinct, and potentially interacting, blood flow streams within the femoral bifurcation during RH. These observations were made possible by the emerging vector flow imaging technique to study complex hemodynamics in vivo, and suggest novel mechanisms by which blood is distributed to vascular beds, in extreme flow profiles.
5.6 Aortic Pressure Behind Flow Disorganization in Aneurismal Aorta: A Magnetic Resonance Imaging Study
Authors: Bouaou Kevin , Dietenbeck Thomas , Soulat Gilles , Houriez—Gombaud-Saintonge Sophia , Bargiotas Ioannis , De Alain Cesare , Gencer Umit , Giron Alain , Redheuil Alban , Bollache Emilie , Lucor Didier , Mousseaux Elie , Kachenoura Nadjia 
Published: March 2020

Abstract
Purpose
Understanding and prediction of ascending thoracic aortic aneurysms (ATAA) progression are not well established yet and aortic dissection is frequently occurring on normally sized and mildly dilated aortas. Despite known theoretical associations between pressures and blood flow patterns there are no studies focusing on their simultaneous evaluation. Our aim was to propose a comprehensive and quantitative evaluation of pressure-flow-wall interplay from 4D flow MRI in the setting of aortic dilation.

Methods
We studied 12 patients with ATAA (67 ± 14 years, 7 males) and 12 healthy subjects (63 ± 12 years, 8 males) who underwent 4D flow MRI. The segmented velocity fields were used to estimate: 1) local ascending aorta (AA) pressure changes from Navier-Stokes-derived relative pressure maps (AADP, mmHg), 2) AA wall shear stress (AAWSS, Pa) by estimating local velocity derivatives at the aortic borders, 3) aortic flow vorticity using the λ2 method (AAV, s-1).

Results
AA local pressure change (AADP) was significantly associated with both AAV (r = 0.55, p = 0.006) and AAWSS (r = 0.69, p < 0.001) and both associations remained significant after adjustment for diameter, age and BSA (p = 0.007 and p = 0.003 respectively). Such positive associations indicate that local pressure variations affect local blood flow, generating flow current from high to low pressures and subsequently vortices with the underlying stress exerted on the AA wall.

Conclusion
Local variations in aortic pressures, measured using 4D flow MRI, are associated with flow disorganization as quantified by vorticity and with the increase in the stress exerted on the aortic wall, as quantified by wall shear stress.
P1 Biomechanical Properties of the Aortic Dissection Flap in Chronic Aortic Dissection
Authors: Panpho Phakakorn , Davies Hannah , Field Mark , Madine Jillian , Yang Ying , Akhtar Riaz 
Published: March 2020

Abstract
Background
Aortic dissection is a devastating condition, beginning with a tear through from intima to the medial layer, leading to splitting of aortic layers and creating the false and true lumen with a septum (or flap). Little is known about the properties of the dissection flap.

Aim
To determine the time-dependent (creep) biomechanical behaviour and biochemical properties of the dissection flap.

Methods
15 descending thoracic aorta samples were obtained from patients undergoing elective surgery for chronic dissected aneurysms. Creep was measured using a non-destructive ball indentation technique utilising a stainless-steel ball over 5 hours. Images were obtained using a long focal distance objective microscope. Remaining tissues were used to determine elastin and glycosaminoglycan (GAG) levels.

Results
The elastic modulus (tissue stiffness) was 64.68 ± 11 kPa and 55.1 ± 9.5 kPa for the flap and true aortic wall respectively. Over 5 hours, the central deformation of the flap tissue was found to be 0.52 ± 0.07 mm as compared to 0.67 ± 0.07 mm for the true aortic wall (p < 0.05). Elastin levels were 126.8 ± 37.25 mg/mg for the flap and 79.82 ± 19.64 mg/mg for the true aortic wall (p < 0.05). The GAG levels were 4.2 mg/mg ± 0.9 mg/mg for the flap and 3.0 ± 0.5 mg/mg (p < 0.05).

Conclusion
The dissection flap exhibits reduced time-dependent deformation and has higher levels of elastin and GAG relative to the aortic wall. These findings may help develop bespoke surgical treatments based on the unique biomechanical and biochemical properties that have been identified.
P4 Aldosterone-Induced Vascular Dysfunction by Decreasing Nuclear Factor Erythroid 2—Related Factor 2 Activity and Increasing Reactive Oxygen Species Generation
Authors: Rodrigues Daniel , da Costa Tiago Januário , da Costa Rafael Menezes , de Passaglia Rita Cássia Aleixo Tostes 
Published: March 2020

Abstract
Introduction
Chronic increases in aldosterone (Aldo) levels (hyperaldosteronism) increases blood pressure and induces hypertension. In the cardiovascular system, Aldo stimulates reactive oxygen species (ROS) generation. ROS contribute to vascular dysfunction by increasing vascular smooth muscle contractile tone, among other effects. Nuclear factor erythroid 2–related factor 2 (Nrf2), it’s one of the main factors in the adaptive response to oxidative stress.

Hypothesis
Aldo negatively regulates the antioxidant system Nrf2, favoring ROS accumulation and subsequent vascular dysfunction.

Methods
Vascular function was evaluated in mice aortic conductance arteries, by performing concentration-effect curves to phenylephrine (PE) and acetylcholine (ACh). ROS production, determined by lucigenin and AmplexRed chemiluminescence, and Nrf2 activity by a nuclear translocation assay, were determined in endothelial cells (EA.hy926).

Results
Aldo increased PE contractions and decreased the relaxation response to ACh. L-sulforaphane, a Nrf2 activator, prevented Aldo-induced vascular dysfunction. In endothelial cells, Aldo increased ROS generation, i.e. superoxide anion and hydrogen peroxide, in a time-dependent manner. In addition, Aldo increased Nrf2 translocation at 30 min, 1 and 3 hours. However, after 3 hours, Aldo decreased Nrf2 translocation.

Conclusion
These data indicate that Aldo increases ROS in endothelial cells and causes impairment in vascular reactivity, events associated with decreased Nrf2 activity. Financial support: FAPESP (Process Number: 2018/05298-1), CAPES, CNPq. This study was approved by the Ethics Committee on Animal Experimentation of the Ribeirao Preto Medical School (030/2018).
P9 Repeatability and Predictors of a Potentially Blood Pressure-Independent Parameter of Arterial Stiffness
Authors: Butlin Mark , Cox James , Spronck Bart , Tan Isabella , Avolio Alberto 
Published: March 2020

Abstract
Background
Arterial stiffness (e.g., as measured by carotid-femoral pulse wave velocity (cfPWV)) changes acutely with blood pressure (BP). High cfPWV at high BP could be due to structural arterial changes or acute BP effects. Various parameters have been proposed as BP-independent parameters of arterial stiffness. These rely on assumptions to simplify theoretical calculations. This study evaluates a parameter quantifying BP dependency of cfPWV through BP manipulation, avoiding assumptions and mathematical derivations.

Methods
Brachial BP and cfPWV (SphygmoCor XCEL, AtCor Medical, Australia) were assessed in seated and supine position. The postural change invokes a systemic and hydrostatic BP change, thus changing cfPWV. ΔcfPWV/ΔBP was calculated. Repeatability was assessed in 25 participants (28 ± 11 years (mean ± SD), 52% female) across two visits on separate days. Cross-sectional correlation with age, gender, height, weight, seated BP, and supine cfPWV was assessed by stepwise linear regression across 135 participants (49 ± 23 years, 48% female).

Results
Mean ΔcfPWV/ΔBP was 0.061 ± 0.025 m/s/mmHg. Repeatability showed a between-measurement difference of 0.005 ± 0.028 m/s/mmHg (8.2% error on mean). ΔcfPWV/ΔBP was cross-sectionally correlated with seated diastolic BP (standardised β = −0.506, p < 0.001), systolic BP (β = 0.503, p < 0.001), weight (β = −0.220, p = 0.006), and heart rate (β = 0.178, p = 0.039) (model p < 0.05, r2 = 0.264).

Conclusion
ΔcfPWV/ΔBP showed fair repeatability. Notwithstanding accounting for BP, it correlated with typical long-term modifiers of arterial stiffness such as chronic elevated BP and weight. Further studies are required to validate if dividing ΔcfPWV by ΔBP, following acute intervention, creates an acceptable BP-independent arterial stiffness variable before the parameter is investigated for cardiovascular risk prediction to evaluate its clinical utility.
P10 Oscillatory Flow Patterns in Peripheral Conduit Artery are Related to Central Arterial Stiffness in Healthy Subjects
Authors: Badhwar Smriti , Chandran Dinu , Jaryal Ashok , Narang Rajiv , Patel Chetan , Deepak Kishore Kumar 
Published: March 2020

Abstract
Background
Studies in endothelial cell cultures show that oscillating flow pattern leads to endothelial dysfunction [1]. The only factor known to contribute towards oscillatory flows is peripheral arterial conductance [2]. However, contribution of alterations in central arterial properties to oscillatory flows is not established.

Methods
Healthy subjects (n = 28) (Age 51.0 ± 9.4 years) with resting retrograde flow in brachial artery were recruited for the study. Pulsed-wave doppler (M7, MindRay) was used for estimation of blood flow velocity with simultaneous diameter acquisition for shear rate calculation. Oscillatory Shear Index (OSI) was calculated by: Retrograde shear rate/(Anterograde shear rate + Retrograde shear rate). Local and regional central arterial stiffness was estimated using carotid distensibility, compliance and Incremental Elastic Modulus (IEM) (Medical Imaging Applications) and carotid-femoral Pulse Wave Velocity (PWV) using applanation tonometry (SphygmocorÒ) respectively. Peripheral vascular stiffness was assessed by carotid-radial PWV. Forearm vascular resistance was estimated using peripheral mean arterial pressure and mean anterograde flow. Carotid-Intima-Media-Thickness (CIMT) was measured using B-mode ultrasound for subclinical atherosclerotic burden estimation.

Results
Retrograde flow showed a significant positive correlation with IEM, CIMT and Augmentation Index (AI) (r = 0.64, 0.47 and 0.62 respectively) (Figures 1 and 2). A significant negative correlation was seen between retrograde flow and carotid compliance (r = −0.58). OSI correlated positively with IEM (r = 0.56) and AI (r = 0.45).

Conclusion
Results of the current study suggest that oscillatory flow patterns in peripheral conduit artery could originate due to decrease in central arterial compliance possibly because of its impact on the incident pressure wave.
P11 The Role of Smooth Muscle Integrin Alpha V and TGF-Beta Pathways in Vascular Fibrosis
Authors: Raoul Alexandre , Belozertseva Ekaterina , Louis Huguette , Li Zhenlin , Regnault Veronique , Lacolley Patrick 
Published: March 2020

AbstractIt has been demonstrated that arterial stiffness is linked to arterial fibrosis manifested by increased collagen and other extracellular matrix synthesis in smooth muscle cells (SMC). Transmembrane receptors integrins mediating cell-cell and cell-matrix signalling pathways are involved in tissue fibrosis. We study the role of one integrin subunit av in angiotensin II (AngII)-induced SMC proliferation and arterial fibrosis and stiffness using SMC specific knock-out av mouse model (avSMKO) induced in adult mice by injection of tamoxifen. There is no difference in vascular fibrosis in basal conditions between control and mutant mice. However, decreased arterial fibrosis is observed in avSMKO mutant mice after 28-day perfusion of AngII. Analysis of RNA from aorta of control and mutant mice by Affymetrix microarrays indicated an alteration of the TGF-β pathway in AngII-treated mutant mice. In order to examine the mechanism associated to the decreased fibrosis in vascular SMC from avSMKO mice, isolated VSMC from the aorta of control and avSMKO mice were treated with TGF-β1 or AngII. The results indicated that these two treatments increased the expression of collagen, fibronectin and integrin αν at the protein and RNA levels as well as the phosphorylation of ERK and smad2/3 in the control cells. Inactivation of integrin αν partly inhibited all above effects induced by TGF-β1 and AngII. Our study indicates a role of av and TGF-β1 in the arterial fibrogenesis. Therefore, av signaling could be a therapeutic target against arterial fibrosis and stiffness in pathological conditions.
P16 Assessment of Plaque Vulnerability Using a Novel Technique: Multi-spectral Photoacoustic Imaging (CVENT-PAI)
Authors: Imaizumi Yuki , Obeid Hasan , Julia Pierre , Calvet David , Boutouyrie Pierre 
Published: March 2020

Abstract
Background
Identification of intraplaque haemorrhage using magnetic resonance imaging (MRI) is expensive, technically demanding and sometimes uncomfortable. Photoacoustic imaging (PAI) is a new non-invasive technique combining multi-wavelength infrared laser light and ultrasound (US) imaging, able to discriminate blood and other components in the tissues. The measurement by the multi-spectral PAI is likely to be more applicable and therefore could be complementary to MRI.

Objectives
Validate a portable multimodal and multi-wavelength PAI system, for the identification of intraplaque haemorrhage and compare with MRI.

Materials and Methods
Patients underwent carotid MRI, and US. Photoacoustic acquisitions are performed and analysed a posteriori blindly of the status of the subjects and results of MRI/US. All patients gave written informed consent. Histology of plaque will be performed as gold standard.

Results
We included 15 patients (71 ± 5 years old) with carotid stenosis grade of >70% (NASCET). PAI imaging was feasible in all patients. On raw images, only clutter signal can be observed. After adequate post processing, carotid wall with the intima media and plaques were clearly visible with PAI. PAI signal from the lumen can be observed, also strong PAI signals are visible inside the plaque in a reproducible manner. Correspondence between MRI and PAI will be analysed later.

Conclusion
The use of the PAI technique for carotid plaque assessment is feasible, and PAI signal are observed inside the plaque. Further analyses are needed to assess the reflected PAI signal inside the plaque, for haemorrhage detection in the future.
P18 Vascular Aging Index of the Finger Photoplethysmogram: A Validation Study with Vascular Stiffness, Mental Stress, and Day-to-Day Variability
Authors: Tarumi Takashi , Yamabe Takayuki , Sugawara Jun 
Published: March 2020

Abstract
Background
Daily assessment of vascular health may predict cardiovascular incidence. Vascular aging index (VAI) calculated from second derivative of photoplethysmogram (SDPTG) is a simple, non-invasive measure possibly reflecting vascular stiffness. However, the effects of daily life events such as mental stress and day-to-day variability as well as its relation to other indices of vascular stiffness remain unclear.

Purpose
To determine whether VAI measured by finger SDPTG is 1) correlated with peripheral augmentation index (pAI), 2) altered by acute mental stress, and 3) affected by day-to-day variability.

Methods
Simultaneous measurements of finger photoplethysmogram and radial artery tonometry were performed in 68 healthy subjects (age = 22–64 years) of whom 31 subjects were further tested during a 30-second mental arithmetic and 10 subjects underwent day-to-day variability assessment for 5 consecutive days. VAI was calculated from a 20-second segment of photoplethysmogram data [1].

Results
At rest, VAI was positively correlated with pAI (r = 0.62, p < 0.001). During mental arithmetic, VAI increased when compared with the control condition (p = 0.032) whereas pAI did not show significant change. Five day measurements of VAI demonstrated the overall coefficient of variation of 21.1 ± 13.7% across all subjects.

Conclusion
VAI calculated from the finger SDPTG is related to a measure of vascular stiffness and sensitive to mental stress with fair day-to-day variability. These findings suggest that VAI assessment needs to be performed at the quiet resting condition.