1. Although arterial blood flow is recognized as an important modulator of vascular tone and geometry, the effect of acute changes in shear-stress on conduit artery mechanics has not been fully investigated in humans because of technical limitations. 2. To assess, respectively, the effects of decreases and increases in flow and shear stress on radial artery tone and mechanics, arterial pressure (photoplethysmography), total blood viscosity, radial artery internal diameter, wall thickness (echotracking) and blood flow (Doppler) were measured in healthy volunteers (mean (+/-SEM) age 25 +/- 1 years) during a distal flow arrest (n=12) and hand skin heating (n=18). 3. Radial artery flow decreased from 31 +/- 4 to 7 +/- 1 10(-3) L/min during distal flow arrest (P < 0.001) and increased from 10 +/- 2 to 22 +/- 4 and 69 +/- 6 10(-3) L/min during heating (P < 0.001). At mean arterial pressure, these changes in flow were respectively associated with a parallel flow-dependent reduction and increase in diameter and midwall stress. There was no significant modification in mean elastic modulus. Compliance did not change when flow decreased and only increased at the highest level of flow. Finally, the cross-sectional compliance and incremental modulus were fitted as functions of midwall stress. The decrease in flow was associated with an upward shift of the modulus-midwall stress curve and a downward shift of the compliance-midwall stress curve. The increase in flow was associated with a downward shift of the modulus-midwall stress curve and an upward shift of the compliance-midwall stress curve at each level of wall shear stress. 4. By using two different procedures, we obtained similar results concerning the direct effects of increases and decreases in flow on stiffness of the arterial wall and on arterial compliance and demonstrated the presence of a flow-dependent regulation of arterial smooth muscle tone of peripheral conduit arteries in humans.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1046/j.1440-1681.2001.03594.x | DOI Listing |
Disaster Med Public Health Prep
January 2025
Department of Public Health, Graduate School of Public Health, Seoul National University, Seoul, South Korea.
Objective: Disasters often have long-lasting effects on the mental health of people affected by them. This study aimed to examine the trajectories and predictors of mental health in people affected by disasters according to their income level.
Method: This study used data from the "Long-Term Survey on the Change of Life of Disaster Victim" conducted by the National Disaster Management Research Institute.
JMIR Mhealth Uhealth
January 2025
Ludwig Boltzmann Institute for Digital Health and Prevention, Salzburg, Austria.
Background: There has been a surge in the development of apps that aim to improve health, physical activity (PA), and well-being through behavior change. These apps often focus on creating a long-term and sustainable impact on the user. Just-in-time adaptive interventions (JITAIs) that are based on passive sensing of the user's current context (eg, via smartphones and wearables) have been devised to enhance the effectiveness of these apps and foster PA.
View Article and Find Full Text PDFEur J Med Res
January 2025
Department of Rehabilitation Medicine, The Affiliated Hospital of Yunnan University, No. 176 Qingnian Road, Wuhua District, Kunming, Yunnan, China.
Background: Stress hyperglycemia ratio (SHR) has been linked to prognosis of cerebrovascular diseases. Nevertheless, the association between SHR and severe disturbance of consciousness (DC) and mortality among patients with cerebral infarction remains explored. This study seeks to assess the predictive potential of SHR for severe DC and mortality among patients with cerebral infarction.
View Article and Find Full Text PDFGenomics
January 2025
Zhejiang Provincial Key Laboratory for Accurate Diagnosis and Treatment of Chronic Liver Diseases, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325035, China; Hangzhou Medical College, Linan District, Hangzhou 311300, China. Electronic address:
Background: Ferroptosis is associated with alcoholic hepatitis (AH); however, the underlying mechanisms remain unclear.
Methods: Changes in iron content and oxidative stress in AH patients and in vivo and in vitro models were analyzed. Iron homeostasis pathways in the livers of patients with AH were investigated using RNA sequencing.
Eat Behav
January 2025
Department of Health Behavior and Health Education, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109, USA.
The first year postpartum is a sensitive time for maternal eating behaviors including emotional, external and restrained eating, which have all been associated with negative health outcomes. Furthermore, among women with a history of trauma, the stress of the postpartum period and early parenting may replicate feelings of helplessness and overwhelm experienced during childhood trauma, which may further contribute to these eating behaviors. Although evidence has shown how mothers eat during this time has long-term implications for infants' eating and health, limited research has characterized eating trajectories and associations with women's history of childhood trauma exposure during this critical period.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!