Analysis and manegement of laminar blood flow inside a cerebral blood vessel using a finite volume software program for biomedical engineering

2020 ◽  
Vol 190 ◽  
pp. 105384 ◽  
Author(s):  
Shu-Rong Yan ◽  
ShahabNaghdi Sedeh ◽  
Davood Toghraie ◽  
Masoud Afrand ◽  
Loke Kok Foong
Keyword(s):  
Blood Flow ◽  
Blood Vessel ◽  
Finite Volume ◽  
Biomedical Engineering ◽  
Cerebral Blood Vessel ◽  
Software Program

Computer modeling of pulsatile blood flow in elastic artery using a software program for application in biomedical engineering

2020 ◽  
Vol 192 ◽  
pp. 105442 ◽  
Author(s):  
Bahador Sharifzadeh ◽  
Rasool Kalbasi ◽  
Mehdi Jahangiri ◽  
Davood Toghraie ◽  
Arash Karimipour
Keyword(s):  
Blood Flow ◽  
Computer Modeling ◽  
Biomedical Engineering ◽  
Pulsatile Blood Flow ◽  
Software Program ◽  
Elastic Artery

COMPARISON OF ANTIHYPERTENSIVE EFFECT OF MOXONIDINE VERSUS CLONIDINE IN RENAL FAILURE PATIENTS.

2018 ◽  
Vol 6 (9) ◽  
Author(s):  
DR.MATHEW GEORGE ◽  
DR.LINCY JOSEPH ◽  
MRS.DEEPTHI MATHEW ◽  
ALISHA MARIA SHAJI ◽  
BIJI JOSEPH ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Renal Failure ◽  
Blood Flow ◽  
Blood Vessel ◽  
Blood Vessels ◽  
High Blood Pressure ◽  
Antihypertensive Effect ◽  
The Body ◽  
Ability To Work ◽  
Blood Flows

Blood pressure is the force of blood pushing against blood vessel walls as the heart pumps out blood, and high blood pressure, also called hypertension, is an increase in the amount of force that blood places on blood vessels as it moves through the body. Factors that can increase this force include higher blood volume due to extra fluid in the blood and blood vessels that are narrow, stiff, or clogged(1). High blood pressure can damage blood vessels in the kidneys, reducing their ability to work properly. When the force of blood flow is high, blood vessels stretch so blood flows more easily. Eventually, this stretching scars and weakens blood vessels throughout the body, including those in the kidneys.

Blood Vessel Density Measured Using Dynamic Optical Coherence Tomography is a Tool for Wound Healers

2021 ◽  
pp. 153473462110173
Author(s):  
Rajgopal Mani ◽  
Jon Holmes ◽  
Kittipan Rerkasem ◽  
Nikolaos Papanas
Keyword(s):  
Blood Flow ◽  
Optical Coherence Tomography ◽  
Blood Vessel ◽  
Chronic Wounds ◽  
Vessel Density ◽  
Optical Coherence ◽  
Skin Microcirculation ◽  
Wound Edge ◽  
Venous Ulcers ◽  
Oct Imaging

Dynamic optical coherence tomography (D-OCT) is a relatively new technique that may be used to study the substructures in the retina, in the skin and its microcirculation. Furthermore, D-OCT is a validated method of imaging blood flow in skin microcirculation. The skin around venous and mixed arterio-venous ulcers was imaged and found to have tortuous vessels assumed to be angiogenic sprouts, and classified as dots, blobs, coils, clumps, lines, and curves. When these images were analyzed and measurements of vessel density were made, it was observed that the prevalence of coils and clumps in wound borders was significantly greater compared with those at wound centers. This reinforced the belief of inward growth of vessels from wound edge toward wound center which, in turn, reposed confidence in following the wound edge to study healing. D-OCT imaging permits the structure and the function of the microcirculation to be imaged, and vessel density measured. This offers a new vista of skin microcirculation and using it, to better understand angiogenesis in chronic wounds.

Numerical Simulation of Pulsating Flow over Blood Vessel Robot

2012 ◽  
Vol 591-593 ◽  
pp. 1734-1738
Author(s):  
Chun Yan Huang ◽  
Fan Jiang
Keyword(s):  
Numerical Simulation ◽  
Boundary Condition ◽  
Blood Flow ◽  
Blood Vessel ◽  
Surface Pressure ◽  
Blood Parameters ◽  
Pulsating Flow ◽  
Inlet Velocity ◽  
Blood Density

In order to study the influence of pulsating blood flow to robot and blood vessel, UDF programming of the inlet velocity is defined as the boundary condition, and the model simulate the turbulent blood flow. Moreover, in this situation, this paper analyzes the influence caused by blood parameters for the biggest surface pressure on robot. The results are showed that the variation of pressure and velocity is different on different position at 0.08s and 0.27s, and the surface pressure of the robot become greater by the increase of blood density or viscosity.

Coronary vasodilation mediated by T cells expressing choline acetyltransferase

2021 ◽  
Vol 321 (5) ◽  
pp. H933-H939
Author(s):  
Adrian H. Chester ◽  
Ann McCormack ◽  
Edmund J. Miller ◽  
Mohamed N. Ahmed ◽  
Magdi H. Yacoub
Keyword(s):  
T Cells ◽  
Blood Flow ◽  
Blood Vessel ◽  
Coronary Blood Flow ◽  
Choline Acetyltransferase ◽  
Vascular Endothelium ◽  
Coronary Circulation ◽  
Direct Interaction ◽  
Coronary Vasodilation ◽  
Ischemic Events

This study shows ChAT-expressing T cells can induce vasodilation of the blood vessel in the coronary circulation and that this effect relies on a direct interaction between T cells and the coronary vascular endothelium. The study establishes a potential immunomodulatory role for T cells in the coronary circulation. The present findings offer an additional possibility that a deficiency of ChAT-expressing T cells could contribute to reduced coronary blood flow and ischemic events in the myocardium.

scholarly journals Real-Time Longitudinal Evaluation of Tumor Blood Vessels Using a Compact Preclinical Fluorescence Imaging System

Biosensors ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 471
Author(s):  
Hoibin Jeong ◽  
Song-Rae Kim ◽  
Yujung Kang ◽  
Huisu Kim ◽  
Seo-Young Kim ◽  
...  
Keyword(s):  
Blood Flow ◽  
Blood Vessel ◽  
Blood Vessels ◽  
Real Time ◽  
Tumor Angiogenesis ◽  
Imaging System ◽  
Angiogenesis Inhibitors ◽  
Laboratory Unit ◽  
Vessel Volume ◽  
Tumor Blood Vessels

Tumor angiogenesis is enhanced in all types of tumors to supply oxygen and nutrients for their growth and metastasis. With the development of anti-angiogenic drugs, the importance of technology that closely monitors tumor angiogenesis has also been emerging. However, to date, the technology for observing blood vessels requires specialized skills with expensive equipment, thereby limiting its applicability only to the laboratory setting. Here, we used a preclinical optical imaging system for small animals and, for the first time, observed, in real time, the entire process of blood vessel development in tumor-bearing mice injected with indocyanine green. Time-lapse sequential imaging revealed blood vessel volume and blood flow dynamics on a microscopic scale. Upon analyzing fluorescence dynamics at each stage of tumor progression, vessel volume and blood flow were found to increase as the tumor developed. Conversely, these vascular parameters decreased when the mice were treated with angiogenesis inhibitors, which suggests that the effects of drugs targeting angiogenesis can be rapidly and easily screened. The results of this study may help evaluate the efficacy of angiogenesis-targeting drugs by facilitating the observation of tumor blood vessels easily in a laboratory unit without large and complex equipment.

scholarly journals Cerebral Blood Vessel Response to L-dopa and Inhibitor of Peripheral Decarboxylase in Stroke-prone SHR (SHRSP), Stroke-resistant SHR (SHRSR) and Wistar-Kyoto (WKY) Rats

1980 ◽  
Vol 21 (4) ◽  
pp. 574-574
Author(s):  
Krystyna Skolasinska ◽  
Yukio Yamori ◽  
Masahiro Kihara ◽  
Katsumi Ikeda ◽  
Yasuo Nara ◽  
...  
Keyword(s):  
Blood Vessel ◽  
Cerebral Blood Vessel ◽  
Wky Rats ◽  
Vessel Response ◽  
Wistar Kyoto

Abstract 3802: Retinal Vasoreactivity as a Marker of Impaired Cerebral Function in Diabetes

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Julia E Slocomb ◽  
Mary E Lott ◽  
Vikram Shivkumar ◽  
Kerstin Bettermann
Keyword(s):  
Blood Vessel ◽  
Cerebrovascular Disease ◽  
Breath Hold ◽  
Mean Flow ◽  
Cerebral Blood Vessel ◽  
Cerebrovascular Function ◽  
Venous Diameter ◽  
Light Flicker ◽  
The Impact ◽  
Flicker Stimulus

The eye and the brain share embryological, anatomic and physiological similarities, which suggest that the retinal microvasculature may be an ideal surrogate marker of cerebrovascular function. This is intriguing, as the cerebral vasculature cannot be directly measured in a non-invasive manner. In epidemiological studies abnormal retinal Arteriovenous Ratios (AVR) are associated with an increased risk of stroke and cerebrovascular disease. However, the association between retinal vasoreactivity measurements and cerebral blood vessel function remains unknown. An attenuated retinal vasoreactivity may indicate endothelial dysfunction in the eye and brain and may prove to be useful as a marker of cerebrovascular disease in high risk populations such as in diabetics. STUDY GOALS: To examine 1) the impact of diabetes at different disease stages on measures of cerebrovascular function and 2) the relationship between retinal blood vessel reactivity, retinal AVRs and measures of cerebral small vessel function. METHODS: This cohort study included 29 type 2 diabetics, 14 pre-diabetics, and 14 healthy controls (ages: 37 to 75 years). Retinal vasoreactivity was measured with the Dynamic Vessel Analyzer (Imedos, Jena, Germany) following high frequency flicker light stimulation. Cerebrovascular blood flow velocity of the Middle Cerebral Artery (MCA) was assessed by Transcranial Doppler Ultrasound (TCD) (Siemens, USA). RESULTS: Progression of diabetes was found to be significantly associated with attenuation of light flicker stimulus response (P=0.0009 artery, P=0.0001 vein, CI 95%), AVR (P=0.0070, CI 95%), PI (P=0.0202, CI 95%), RI (P=0.0033, CI 95%) and hyperventilation-breath hold (P≤0.0001, CI 95%). Across all groups, attenuated retinal arterial and venous diameter responses to the light flicker stimulus were associated with an increase in MCA RI (P=0.02, r=-0.30 artery, P=0.06, r=-0.24 vein, CI 95%). An attenuated venous diameter response was associated with an increase in PI (P=0.02, r=-0.29 vein, CI 95%). In addition, attenuated retinal diameter responses were also associated with a decrease in MCA mean flow velocities following hyperventilation-breath hold (P=0.05, r=0.26 artery, P=0.01, r=0.34 vein, CI 95%). Attenuated retinal responses were also correlated with a reduction in AVR (P=0.05, r=0.26 artery, P=0.15, r=0.19 vein, CI 95%). CONCLUSION: Impairment of retinal vasoreactivity is associated with cerebrovascular dysfunction across the continuum of diabetes, possibly indicating that the eye reflects changes in cerebral blood vessel function and stroke risk.

The Dll4/Notch pathway controls postangiogenic blood vessel remodeling and regression by modulating vasoconstriction and blood flow

Blood ◽  
2011 ◽  
Vol 117 (24) ◽  
pp. 6728-6737 ◽  
Author(s):  
Ivan B. Lobov ◽  
Eunice Cheung ◽  
Rajeev Wudali ◽  
Jingtai Cao ◽  
Gabor Halasz ◽  
...  
Keyword(s):  
Blood Flow ◽  
Blood Vessel ◽  
Protein A ◽  
Notch Pathway ◽  
Negative Regulator ◽  
Vessel Occlusion ◽  
Vessel Remodeling ◽  
Vessel Morphology ◽  
Independent Functions ◽  
Retinal Capillaries

Abstract Blood vessel remodeling is crucial to the formation of the definitive vasculature, but little is known about the mechanisms controlling this process. We show that Delta-like ligand 4 (Dll4)/Notch pathway regulates vessel regression in normal pathologic conditions. Genetic and pharmacologic inhibition of Dll4/Notch prevented retinal capillary regression in the oxygen-induced retinopathy (OIR) model and during normal development. Deletion of the Notch-regulated ankyrin repeat protein, a negative regulator of the Notch pathway, produced an opposite phenotype. Inhibition of Dll4/Notch reduced vessel occlusion, maintaining blood flow that is essential for survival of microvessels. Dll4/Notch inhibition up-regulated the expression of vasodilators adrenomedullin and suppressed the expression of vasoconstrictor angiotensinogen. Angiotensin II induced rapid nonperfusion and regression of developing retinal capillaries, whereas Ace1 and AT1 inhibitors and adrenomedullin attenuated vasoobliteration in OIR, indicating that both pathways are involved in modulating vessel remodeling. In contrast, inhibition of vascular endothelial growth factor-A (VEGF-A) did not result in a pervasive loss of retinal capillaries, demonstrating that reduced expression of VEGF-A is not the proximate cause of capillary regression in OIR. Modulation of VEGF-A and DII4/Notch signaling produced distinct changes in blood vessel morphology and gene expression, indicating that these pathways can have largely independent functions in vascular remodeling.

Sign in / Sign up

Export Citation Format

Share Document