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1 – 10 of 557Yajing Hu, Botong Li, Xinhui Si, Jing Zhu and Linyu Meng
Atherosclerosis tends to occur in the distinctive carotid sinus, leading to vascular stenosis and then causing death. The purpose of this paper is to investigate the effect of…
Abstract
Purpose
Atherosclerosis tends to occur in the distinctive carotid sinus, leading to vascular stenosis and then causing death. The purpose of this paper is to investigate the effect of sinus sizes, positions and hematocrit on blood flow dynamics and heat transfer by different numerical approaches.
Design/methodology/approach
The fluid flow and heat transfer in the carotid artery with three different sinus sizes, three different sinus locations and four different hematocrits are studied by both computational fluid dynamics (CFD) and fluid-structure interaction (FSI) methods. An ideal geometric model and temperature-dependent non-Newtonian viscosity are adopted, while the wall heat flux concerning convection, radiation and evaporation is used.
Findings
With increasing sinus size, the average velocity and temperature of the blood fluid decrease, and the area of time average wall shear stress (TAWSS)with small values decreases. As the distances between sinuses and bifurcation points increase, the average temperature and the maximum TAWSS decrease. Atherosclerosis is more likely to develop when the sinuses are enlarged, when the sinuses are far from bifurcation points, or when the hematocrit is relatively large or small. The probability of thrombosis forming and developing becomes larger when the sinus becomes larger and the hematocrit is small enough. The movement of the arterial wall obviously reduces the velocity of blood flow, blood temperature and WSS. This study also suggests that the elastic role of arterial walls cannot be ignored.
Originality/value
The hemodynamics of the internal carotid artery sinus in a carotid artery with a bifurcation structure have been investigated thoroughly, on which the impacts of many factors have been considered, including the non-Newtonian behavior of blood and empirical boundary conditions. The results when the FSI is considered and absent are compared.
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Shokoofeh Talebi, Zamzam Paknahad, Mohammad Hashemi and Akbar Hasanzadeh
Coronary artery disease (CAD) is developed by an insufficient supply of oxygen-rich blood to the myocardium. Recent studies have shown that increased oxidative stress has…
Abstract
Purpose
Coronary artery disease (CAD) is developed by an insufficient supply of oxygen-rich blood to the myocardium. Recent studies have shown that increased oxidative stress has implicated in the pathogenesis of coronary atherosclerosis. Anxiety and CAD have a mutual relationship, as the effect of long-lasting anxiety on atherosclerosis and CAD is well known. The purpose of this study is to investigate the relationship between dietary / serum total antioxidant capacity and CAD.
Design/methodology/approach
A total of 160 male patients were enrolled in this cross-sectional study. Diagnosis and analysis of angiograms were performed visually by a cardiologist. The subjects were categorized into CAD− (coronary artery obstruction <75 per cent) and CAD+ (coronary artery obstruction ≥ 75 per cent) groups. Anthropometric indices, blood pressure, blood sugar and lipid profile and physical activity (PA) were assessed. Information about anxiety was obtained by Spielberger questionnaire. Dietary total antioxidant capacity (TAC) was obtained by using a semi-quantitative food frequency questionnaire and an oxygen radical absorbance capacity of selected foods.
Findings
Mean of dietary TAC was significantly lower in CAD+ than CAD− group (P < 0.001). However, there was not any significant differences about serum TAC (P = 0.28). The mean of body mass index (BMI) (P = 0.04) and triglyceride (TG) level (P = 0.03) and the frequency of smoking (P = 0.03) were significantly higher in the CAD+ than the CAD− group. There was no significant relationship between CAD with apparent (P = 0.33) and hidden anxiety level (P = 0.16). Confounding factors such as smoking and medications were adjusted.
Research limitations/implications
This study had certain limitations. Being a single center cross-sectional design does not permit analysis of causal relationships; the sample size was geographically limited. The authors could not exclude the medication of patients, which could affect the total antioxidant capacity levels. Measurement error in self-reported dietary consumption may results misclassification of exposure.
Practical implications
A diet high in total antioxidant capacity is inversely associated with CAD. Serum TAC does not vary between men with and without CAD when confounders including age, BMI, TG, smoking, SBP, DBP, energy intake, PA, HDL-C, LDL-C, T-C, FBS, family history of CAD, education and anxiety are taken into consideration.
Social implications
High consumption of vegetables and fruits may play a major role in the prevention of CAD.
Originality/value
The study was approved by the ethics committee of Isfahan University of Medical Sciences (No:394888).
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D.K. Mandal, N.K. Manna and S. Chakrabarti
This paper aims to perform numerical simulations through different shaped double stenoses in a vascular tube for a better understanding of arterial blood flow patterns, and their…
Abstract
Purpose
This paper aims to perform numerical simulations through different shaped double stenoses in a vascular tube for a better understanding of arterial blood flow patterns, and their possible role during the progression of atherosclerosis. The dynamics of flow features have been studied by wall pressure, streamline contour and wall shear stress distributions for all models.
Design/methodology/approach
A finite volume method has been employed to solve the governing equations for the two‐dimensional, steady, laminar flow of an incompressible and Newtonian fluid.
Findings
The paper finds that impact of pressure drop, reattachment length and peak wall shear stress at each restriction primarily depends upon percentage of restriction, if restriction spacing is sufficient. The quantum of impact of pressure drop, reattachment length and peak wall shear stress is much effected for smaller restriction spacing. If recirculating bubble of first restriction merges with the recirculating bubble formed behind the second restriction in this smaller restriction spacing. The similar effect of smaller restriction spacing is observed, if Reynolds number increases also.
Originality/value
The effect of different shaped stenoses, restriction spacing and Reynolds number on the flow characteristics has been investigated and the role of all the flow characteristics on the progression of the disease, atherosclerosis, is discussed.
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Hossein Tamim, Abbas Abbassi and Nasser Fatouraee
The purpose of this paper is to analyze the influence of curvature on the transport of low-density lipoprotein (LDL) through a curved artery and concentration boundary layer…
Abstract
Purpose
The purpose of this paper is to analyze the influence of curvature on the transport of low-density lipoprotein (LDL) through a curved artery and concentration boundary layer characteristics numerically.
Design/methodology/approach
By using a projection method based on the second-order central difference discretization, the authors solve the set of governing equations, which consists of Navier–Stokes, continuity and species transport. The effects of initial straight length, as well as the curvature and wall shear stress (WSS) on LDL transport in a curved artery are established in this paper.
Findings
The obtained numerical results imply that the LDL concentration boundary layer thickness decreases in the outer part of the curved artery and increases in the inner part for both with or without initial straight length. The effect of Reynolds number on the concentration distribution in a curved artery with initial straight length is more pronounced than that on a fully curved artery, although an opposite trend was seen for the curvature ratio. The maximum surface LDL concentration is related to the regions with minimum WSS in the inner part of the curved artery, which has more potential the formation of atherosclerosis.
Originality/value
The authors present a comprehensive concentration distribution of LDL in the concentration boundary layer of the curved artery. The authors also characterize and predict the influence of curvature on the formation and development of atherosclerosis within the arterial wall.
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The health problem commonly associated with consuming a diet rich incholesterol – what is generally termed atherosclerosis – is widespread inthe Western world and the single most…
Abstract
The health problem commonly associated with consuming a diet rich in cholesterol – what is generally termed atherosclerosis – is widespread in the Western world and the single most prevalent cause of death. Public awareness about cholesterol is, however, patchy owing to conflicting and confusing information in the media. Attempts to give an understanding about chemical composition, the mode of presence, metabolism, and other general current information and practices about cholesterol and how it may be controlled to maintain safe levels in the body.
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Mohammad Gholizadeh, Ebrahim Falahi, Ammar Hassanzadeh Keshteli, Ahmadreza Yazdan Nik, Parvane Saneei, Ahmad Esmaillzadeh and Ahmad Saedisomeolia
Dietary inflammatory potential (DIP) is a novel dietary index designed to evaluate individuals’ diets with considering inflammation and anti-inflammation score. In addition…
Abstract
Purpose
Dietary inflammatory potential (DIP) is a novel dietary index designed to evaluate individuals’ diets with considering inflammation and anti-inflammation score. In addition, adhesion molecules including soluble intracellular adhesion molecules-1 (sICAM-1), soluble cellular adhesion molecules-1 (sVCAM-1) and E-selectin are important biomarkers to assess endothelium dysfunction which are related to atherosclerosis and cardiovascular complications. Also, there is no study for assessing the association between adhesion molecules and DIP until now as well as other studies that assessed the relationship between dietary inflammatory index or DIP has controversy. The purpose of this cross-sectional study was to determine the correlation between DIP and endothelial markers such as E-selectin, sICAM-1 and sVCAM-1 among female nurses from Isfahan. In this study, DIP was used instead of DII.
Design/methodology/approach
This study was performed on 420 healthy nurses. The nurses were selected by random cluster sampling method from private and public Isfahan hospitals. A validated food frequency questionnaire (FFQ) was applied to assess the DIP. A fasting blood sample was collected for measuring the plasma levels of the endothelial markers and other variables.
Findings
After adjusting different potential confounders, no statistical association was found between DIP and sICAM-1, E–selectin and sVCAM-1 in Model I (P = 0.57, 0.98 and 0.45), Model II (P = 0.57, 0.98 and 0.45) and Model III (P = 0.67, 0.92 and 0.50) in comparison to the crude group (P = 0.35, 0.83 and 0.49, respectively).
Originality/value
The results revealed that the plasma levels of endothelial markers including E-selectin, sICAM-1 and sVCAM-1 were not significantly associated with DIP in female nurses.
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– The purpose of this paper is to explore consumers’ perceptions and beliefs in the health benefits of wine and the relationship with wine consumption patterns.
Abstract
Purpose
The purpose of this paper is to explore consumers’ perceptions and beliefs in the health benefits of wine and the relationship with wine consumption patterns.
Design/methodology/approach
In store face-to-face survey results from 402 wine consumers were elaborated with two-step cluster analysis. ANOVA confirmed differences among groups. Groups were profiled by a χ2 significance analysis when adequate. A multivariate binary logistic regression estimated wine consumption influence on healthiness perceptions.
Findings
Consumers converge into four groups: two health-oriented – optimistic and medical; two non-health-oriented – unintentional drinker and unconvinced. Groups are not significantly differentiated in socio-economic terms. Wine consumption behaviour influences health orientation, specifically for monthly and wine drinkers, vs weekly and other alcohol drinkers. Health-oriented consumers favourably welcome and are willing to pay more for health-enhancing wine. Consumers believe that wine consumption mainly benefits atherosclerosis and hypertension.
Research limitations/implications
Since health-oriented wine is not common in the market, consumers provided answers based on their experience with other health-oriented food and beverages and on the common appreciation of the “terroir” perspective. Future research could extend the analysis on health claims and nutrition claims through blind wine tasting, price range acceptability and market potential dimensions.
Practical implications
The high number of wine SKUs and consumer interest in wine healthiness suggest wine manufacturers should invest in health-oriented differentiation strategies, focused on atherosclerosis and hypertension claims and higher prices.
Social implications
Given worldwide wine consumption, the research findings contribute to public health policy by addressing alcoholism and promoting healthy consumption behaviour.
Originality/value
The findings provide insights for private and public sectors to support innovative approaches for the development of health-promoting food system.
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Chandan Kumawat, Bhupendra Kumar Sharma, Taseer Muhammad and Liaqat Ali
The purpose of this study is to determine the impact of two-phase power law nanofluid on a curved arterial blood flow under the presence of ovelapped stenosis. Over the past…
Abstract
Purpose
The purpose of this study is to determine the impact of two-phase power law nanofluid on a curved arterial blood flow under the presence of ovelapped stenosis. Over the past couple of decades, the percentage of deaths associated with blood vessel diseases has risen sharply to nearly one third of all fatalities. For vascular disease to be stopped in its tracks, it is essential to understand the vascular geometry and blood flow within the artery. In recent scenarios, because of higher thermal properties and the ability to move across stenosis and tumor cells, nanoparticles are becoming a more common and effective approach in treating cardiovascular diseases and cancer cells.
Design/methodology/approach
The present mathematical study investigates the blood flow behavior in the overlapped stenosed curved artery with cylinder shape catheter. The induced magnetic field and entropy generation for blood flow in the presence of a heat source, magnetic field and nanoparticle (Fe3O4) have been analyzed numerically. Blood is considered in artery as two-phases: core and plasma region. Power-law fluid has been considered for core region fluid, whereas Newtonian fluid is considered in the plasma region. Strongly implicit Stone’s method has been considered to solve the system of nonlinear partial differential equations (PDE’s) with 10–6 tolerance error.
Findings
The influence of various parameters has been discussed graphically. This study concludes that arterial curvature increases the probability of atherosclerosis deposition, while using an external heating source flow temperature and entropy production. In addition, if the thermal treatment procedure is carried out inside a magnetic field, it will aid in controlling blood flow velocity.
Originality/value
The findings of this computational analysis hold great significance for clinical researchers and biologists, as they offer the ability to anticipate the occurrence of endothelial cell injury and plaque accumulation in curved arteries with specific wall shear stress patterns. Consequently, these insights may contribute to the potential alleviation of the severity of these illnesses. Furthermore, the application of nanoparticles and external heat sources in the discipline of blood circulation has potential in the medically healing of illness conditions such as stenosis, cancer cells and muscular discomfort through the usage of beneficial effects.
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The origins of ischaemic heart disease are obscure. The articlediscusses the influence of environment, heredity and diet (especiallyfor consumption). It is then proposed that…
Abstract
The origins of ischaemic heart disease are obscure. The article discusses the influence of environment, heredity and diet (especially for consumption). It is then proposed that dietary deficiencies of copper may be a factor that enhances risk of the disease. The evidence for this is discussed.
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Hedieh Alavi Talab, Mehdi Ardjmand, Abbasali Motallebi and Reza Pourgholam
Extraction and purification of Hypophthalmichthys molitrix fish oil by urea complex formation were made at −5, +1 and +5 ○C, respectively. Omega‐3 polyunsaturated fatty acids…
Abstract
Purpose
Extraction and purification of Hypophthalmichthys molitrix fish oil by urea complex formation were made at −5, +1 and +5 ○C, respectively. Omega‐3 polyunsaturated fatty acids (PUFA) have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia. Starting with the hypothesis that the observed low cardiovascular morality could be related to marine diet, which contains omega‐3 PUFA.
Design/methodology/approach
Fish oil was extracted by Bligh and Dyer method from the muscle tissue and after, the PUFA concentrates produced by urea complexation and the oil samples were stored at −70 ○C. The observed results show that the rate of omega‐3 extraction has been increased while saturated and long chain monosaturated fatty acids decreased during this process.
Findings
Eicosapentaenoic acid (EPA) has a higher tendency to form urea adducts than the other two major n‐3 PUFAs, especially at low temperatures. The optimum temperature for maximum recovery of EPA is about 1 ○C. The amount of extracted omega‐3 in H. molitrix oil were 20.58 per cent wt of total extracted oil and by subsequent purification increased to 68 per cent wt at 1 ○C, 36.82 per cent wt at +5 ○C and 22.53 per cent wt at −5 ○C of total extracted oil.
Practical implications
Omega‐3 PUFA have proved to be beneficial in atherosclerosis, arrhythmia and hypertriglyceridemia. Starting with the hypothesis that the observed low cardiovascular morality could be related to marine diet, which contains omega‐3 PUFA. In order to reduce the risk of cardiovascular diseases, emphasis has now been placed on the increased consumption of fish and fish products which are rich in PUFA.
Originality/value
The amount of extracted omega‐3 in H. molitrix oil were 20.58 per cent wt of total extracted oil and by subsequent purification increased to 68 per cent wt at 1 ○C, 36.82 per cent wt at +5 ○C and 22.53 per cent wt at −5 ○C of total extracted oil. Due to the low price of H. molitrix in comparison to other ocean fish sources, as well as, its availability in all seasons, higher level of ω3‐fatty acids, H. molitrix species has a good potential for ω3‐fatty acids production by extraction and subsequent purification.
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