Plaques In Blood Vessels Research Articles

The Impact of Metabolic and Bariatric Surgery on Apo B100 Levels in Individuals with high BMI: A Multi-Centric Prospective Cohort Study.

Metabolic and Bariatric surgery (MBS) leads to significant weight loss and improvements in obesity-related comorbidities. However, the impact of MBS on Apolipoprotein B100 (Apo-B100) regulation is unclear. Apo-B100 is essential for the assembly and secretion of serum lipoprotein particles. Elevated levels of these factors can accelerate the development of atherosclerotic plaques in blood vessels. This study aimed to evaluate changes in Apo-B100 levels following MBS. 121 participants from the Iranian National Obesity and Metabolic Surgery Database (INOSD) underwent Laparoscopic Sleeve Gastrectomy (LSG) (n = 43), One-Anastomosis Gastric Bypass (OAGB) (n = 70) or Roux-en-Y Gastric Bypass (RYGB) (n = 8). Serum Apo-B100, lipid profiles, liver enzymes, and fasting glucose were measured preoperatively and six months postoperatively. Apo-B100 levels significantly decreased from 94.63 ± 14.35 mg/dL preoperatively to 62.97 ± 19.97 mg/dL after six months (p < 0.01), alongside reductions in total cholesterol, triglycerides, LDL, VLDL, AST, and ALT (p < 0.05). Greater Apo-B100 reductions occurred in non-diabetics versus people with diabetes (p = 0.012) and strongly correlated with baseline Apo-B100 (r = 0.455, p < 0.01) and LDL levels (r = 0.413, p < 0.01). However, surgery type did not impact Apo-B100 changes in multivariate analysis (p > 0.05). Bariatric surgery leads to a significant reduction in Apo-B100 levels and improvements in lipid profiles and liver enzymes, indicating a positive impact on dyslipidemia and cardiovascular risk in individuals with high BMI.

Tetrazine-Based Ratiometric Nitric Oxide Sensor Identifies Endogenous Nitric Oxide in Atherosclerosis Plaques by Riding Macrophages as a Smart Vehicle.

Atherosclerosis (AS) is the formation of plaques in blood vessels, which leads to serious cardiovascular diseases. Current research has disclosed that the formation of AS plaques is highly related to the foaming of macrophages. However, there is a lack of detailed molecular biological mechanisms. We proposed a "live sensor" by grafting a tetrazine-based ratiometric NO probe within macrophages through metabolic and bio-orthogonal labeling. This "live sensor" was proved to target the AS plaques with a diameter of only tens of micrometers specifically and visualized endogenous NO at two lesion stages in the AS mouse model. The ratiometric signals from the probe confirmed the participation of NO during AS and indicated that the generation of endogenous NO increased significantly as the lesion progressed. Our proposal of this "live sensor" provided a native and smart strategy to target and deliver small molecular probes to the AS plaques at the in vivo level, which can be used as universal platforms for the detection of reactive molecules or microenvironmental factors in AS.

Structural insights on the deformations induced by various mutations on cholesteryl ester transfer protein

Cholesteryl Ester Transfer Protein (CETP) is a plasma glycoprotein that intervenes the reverse cholesterol transport (RCT) by equimolar exchange of Cholesteryl esters (CE) and Triglycerides (TGs) between anti-atherogenic High-Density Lipoproteins (HDLs) and pro-atherogenic Low-Density Lipoproteins (LDLs) resulting in the increased concentration of CEs in LDL. This is a potential cause for the formation of atherosclerotic plaques in blood vessels leading to fatality. Therefore, blocking the function of CETP has emerged as a novel strategy for suppressing atherosclerotic plaques. The crystal structure of CETP revealed two Cholesteryl esters (CEs) in the hydrophobic tunnel and two phospholipids (PLs) plugged on the concave surface. Previous lipid transfer assay experimental studies have shown a substantial reduction in the neutral lipid transfer in [R201S] and [I443W, V198W] mutants. However, the protein conformational arrangements due to the mutations present in the CETP system leading to a decrease in the transfer rate of neutral lipids is not explored. Thus, I explored the reason behind the decreased transfer rate in mutants using molecular dynamics (MD) simulations and free energy calculations. Resulting evidences show that R201S mutant induces unfavorable bending angle to CETP with a decreased binding efficiency between N-terminal phospholipid of CETP with S201. Also, an unfavorable conformation state of TGs is formed which makes them difficult to transfer across CETP. Likewise, [I443W, V198W] mutant induces unfavorable CE, TG, and bending angle conformation to CETP impeding neutral lipid transfer. Thus, my results provide sufficient insights on the causation for a decreased transfer rate as reported earlier. The detailed understanding obtained here could help in developing a new strategy in preventing the function of CETP by blocking the role of potential hot spot residues.

Characterization of atherosclerotic plaques in blood vessels with low oxygenated blood and blood pressure (Pulmonary trunk): role of growth differentiation factor-15 (GDF-15)

BackgroundGrowth differentiation factor (GDF)-15 is linked to inflammation, cancer, and atherosclerosis. GDF-15 is expressed in most tissues but is extremely induced under pathological conditions. Elevated serum levels are suggested as a risk factor and a marker for cardiovascular diseases. However, the cellular sources and the effects of GDF-15 on the cardiovascular system have not been completely elucidated including progression, and morphology of atherosclerotic plaques. Thus, this work aimed to characterize the influence of GDF-15 deficiency on the morphology of atherosclerotic plaques in blood vessels with low-oxygen blood and low blood pressure as the pulmonary trunk (PT), in hypercholesterolemic ApoE−/− mice.MethodsGDF-15−/− ApoE−/− mice were generated by crossbreeding of ApoE−/−- and GDF-15−/− mice. After feeding a cholesterol-enriched diet (CED) for 20 weeks, samples of the brachiocephalic trunk (BT) and PT were dissected and lumen stenosis (LS) was measured. Furthermore, changes in the cellularity of the PT, amounts of apoptosis-, autophagy-, inflammation- and proliferation-relevant proteins were immunohisto-morphometrically analyzed. Additionally, we examined an atherosclerotic plaque in a human post mortem sample of the pulmonary artery.ResultsAfter CED the body weight of GDF-15−/−ApoE−/− was 22.9% higher than ApoE−/−. Double knockout mice showed also an 35.3% increase of plasma triglyceride levels, whereas plasma cholesterol was similar in both genotypes. LS in the BT and PT of GDF-15−/−ApoE−/− mice was significantly reduced by 19.0% and by 6.7% compared to ApoE−/−. Comparing LS in PT and BT of the same genotype revealed a significant 38.8% (ApoE−/−) or 26.4% (GDF-15−/−ApoE−/−) lower LS in the PT. Immunohistomorphometry of atherosclerotic lesions in PT of GDF-15−/−ApoE−/− revealed significantly increased levels (39.8% and 7.3%) of CD68 + macrophages (MΦ) and α-actin + smooth muscle cells than in ApoE−/−. The density of TUNEL + , apoptotic cells was significantly (32.9%) higher in plaques of PT of GDF-15−/−ApoE−/− than in ApoE−/−. Analysis of atherosclerotic lesion of a human pulmonary artery showed sm-α-actin, CD68+, TUNEL+, Ki67+, and APG5L/ATG+ cells as observed in PT. COX-2+ and IL-6+ immunoreactivities were predominantly located in endothelial cells and subendothelial space. In BT and PT of GDF15−/−ApoE−/− mice the necrotic area was 10% and 6.5% lower than in ApoE−/−. In BT and PT of GDF15−/−ApoE−/− we found 40% and 57% less unstable plaques than ApoE−/− mice.ConclusionsAtherosclerotic lesions occur in both, BT and PT, however, the size is smaller in PT, possibly due to the effect of the low-oxygen blood and/or lower blood pressure. GDF-15 is involved in atherosclerotic processes in BT and PT, although different mechanisms (e.g. apoptosis) in these two vessels seem to exist.

Is there life after acute coronary syndrome?

The role of coronary heart disease and acute coronary syndrome in the structure of morbidity and mortality of the population of Ukraine cannot be overestimated. The main pathogenetic mechanism of corticosteroids is atherothrombosis, the influence of which is the basis of treatment of patients with coronary heart disease with or without corticosteroids. The effect on the progression of atherothrombosis is possible due to statins, due to slowing the growth of atherosclerotic plaques in blood vessels by reducing the level of low-density lipoproteins in the blood.

Some calcium-channel blockers: kinetic and in silico studies on paraoxonase-I

Many drugs, which are used in clinical treatments, show pharmacological effects on enzyme activity with an essential role in the pathogenesis of various diseases. Paraoxonase-I (PON1) is a member of the mammalian lactonase enzyme family, serves to the prevention of blood vessel plaque formation by protecting high-density lipoprotein and low-density lipoprotein against oxidation. In the current study, we aimed to contribute to drug discovery and to determine the interaction of some calcium channel blockers (CCBs) with PON1. For this purpose, first, the PON1 enzyme was purified from fresh human serum by using different chromatographic techniques. Then, the various concentrations of CCBs were tested on the paraoxonase activity of PON1. IC 50 values were found as 41.00, 48.00, and 180 µM for nimodipine, cinnarizine, and nilvadipine, respectively. PON1 was effectively inhibited by these drugs (K is ranging between 22.13 ± 1.13 and 174.12 ± 20.52 µM). Of these drugs, only the inhibition mechanism of cinnarizine was competitive on PON1. Besides, the molecular docking analysis of cinnarizine was applied to detailed the binding interactions on the active site of PON1. The docking scores for the Glide standard-precision (SP), and Glide extra-precision (XP) modes for 1V04 receptor monitored to be −5.001, and −6.079, respectively. We determined that the CCBs reduced PON1 enzyme activity both in vitro and in silico conditions, significantly. Therefore, further biological studies such as gene expression and in vivo experiments should be done for these drugs. Communicated by Ramaswamy H. Sarma

OPTIMASI DESAIN STENT PLA MENGGUNAKAN METODE RESPONSE SURFACE (RSM) UNTUK MEMPEROLAH FLEKSIBILITAS TERBAIK

The stent installation is one of cardiovascular disease treatments which is selected the most to handle patients with blood vessel disease. As the demand for stents increases, more researches are aimed at developing them. This study aims to obtain the optimal link design to produce the best flexibility to the change of stent angle with minimum stress so as not to injure blood vessel plaque. In this study, the stents are polymer stent with different types of links made with PLA materials with strut mirror (S&gt;&lt;) design. The study was conducted on two stent configurations, namely crimped and expanded to determine the ability of angular change and maximum stress experienced by both when bending moment applied. The bending moment test was done through simulation based on finite element method in software Abaqus 6.14. The simulation results were then used as a model-making reference to determine the desired optimization design using the help of Minitab 18 software based on the response surface method. The results of this study indicate that the best optimal flexibility on crimped stent L1 to L5, which is the highest flexibility with von mises stress in the safety limit can be obtained based on a combination of link design parameters in the form of bending moment of 0.0074 N.mm with a thickness of 100 μm L3, and 0,0087 N.mm with a thickness of 106 μm L5. While at the expanded stent L1 to L5, the optimal link design parameter value for obtaining the best flexibility with von mises stress within the safety limit is a bending moment of 0.0075 N.mm with a thickness of 63.78 μm L3, 0.0067 N.mm with a thickness of 70 μm L5.

Development of a thresholding algorithm for calcium classification at multiple CT energies

The objective of this study was to develop a thresholding method for calcium classification with different concentration using single-energy computed tomography. Five different concentrations of calcium chloride were filled in PMMA tubes and placed inside a water-filled PMMA phantom (diameter 10 cm). The phantom was scanned at 70, 80, 100, 120 and 140 kV using a SECT. CARE DOSE 4D was used and the slice thickness was set to 1 mm for all energies. ImageJ software inspired by the National Institute of Health (NIH) was used to measure the CT numbers for each calcium concentration from the CT images. The results were compared with a developed algorithm for verification. The percentage differences between the measured CT numbers obtained from the developed algorithm and the ImageJ show similar results. The multi-thresholding algorithm was found to be able to distinguish different concentrations of calcium chloride. However, it was unable to detect low concentrations of calcium chloride and iron (III) nitrate with CT numbers between 25 HU and 65 HU. The developed thresholding method used in this study may help to differentiate between calcium plaques and other types of plaques in blood vessels as it is proven to have a good ability to detect the high concentration of the calcium chloride. However, the algorithm needs to be improved to solve the limitations of detecting calcium chloride solution which has a similar CT number with iron (III) nitrate solution.

Elastin-like-recombinamers multilayered nanofibrous scaffolds for cardiovascular applications

Coronary angioplasty is the most widely used technique for removing atherosclerotic plaques in blood vessels. The regeneration of the damaged intima layer after this treatment is still one of the major challenges in the field of cardiovascular tissue engineering. Different polymers have been used in scaffold manufacturing in order to improve tissue regeneration. Elastin-mimetic polymers are a new class of molecules that have been synthesized and used to obtain small diameter fibers with specific morphological characteristics. Elastin-like polymers produced by recombinant techniques and called elastin-like recombinamers (ELRs) are particularly promising due to their high degree of functionalization. Generally speaking, ELRs can show more complex molecular designs and a tighter control of their sequence than other chemically synthetized polymers Rodriguez Cabello et al (2009 Polymer 50 5159–69, 2011 Nanomedicine 6 111–22). For the fabrication of small diameter fibers, different ELRs were dissolved in 2,2,2-fluoroethanol (TFE). Dynamic light scattering was used to identify the transition temperature and get a deep characterization of the transition behavior of the recombinamers. In this work, we describe the use of electrospinning technique for the manufacturing of an elastic fibrous scaffold; the obtained fibers were characterized and their cytocompatibility was tested in vitro. A thorough study of the influence of voltage, flow rate and distance was carried out in order to determine the appropriate parameters to obtain fibrous mats without beads and defects. Moreover, using a rotating mandrel, we fabricated a tubular scaffold in which ELRs containing different cell adhesion sequences (mainly REDV and RGD) were collected. The stability of the scaffold was improved by using genipin as a crosslinking agent. Genipin-ELRs crosslinked scaffolds show a good stability and fiber morphology. Human umbilical vein endothelial cells were used to assess the in vitro bioactivity of the cell adhesion domains within the backbone of the ELRs.

Long-term simulation of large deformation, mechano-chemical fluid-structure interactions in ALE and fully Eulerian coordinates

In this work, we develop numerical schemes for mechano-chemical fluid-structure interactions with long-term effects. We investigate a model of a growing solid interacting with an incompressible fluid. A typical example for such a situation is the formation and growth of plaque in blood vessels. This application includes two particular difficulties: First, growth may lead to very large deformations, up to full clogging of the fluid domain. We derive a simplified set of equations including a fluid-structure interaction system coupled to an ODE model for plaque growth in Arbitrary Lagrangian Eulerian (ALE) coordinates and in Eulerian coordinates. The latter novel technique is capable of handling very large deformations up to contact. The second difficulty stems from the different time scales: while the dynamics of the fluid demand to resolve a scale of seconds, growth typically takes place in a range of months. We propose a temporal two-scale approach using local small-scale problems to compute an effective wall stress that will enter a long-scale problem. Our proposed techniques are substantiated with several numerical tests that include comparisons of the Eulerian and ALE approaches as well as convergence studies.

Combination probe for optically assisted ultrasonic velocity-change imaging aimed at detecting unstable blood vessel plaque

Blood vessel plaque with a large lipid core is at risk of becoming thrombus and is likely to induce acute heart disease. To prevent this, it is necessary to determine not only the plaque’s size but also its chemical composition. We, therefore, made the prototype of a combination probe to diagnose carotid artery plaque. It is used to differentiate propagation characteristics between light spectra and ultrasonic images. By propagating light and ultrasound along a common direction, it is possible to effectively warm the diagnosis domain. Moreover, the probe is thought to be compact and be easy to use for diagnosing human carotid artery plaque. We applied the combination probe to a carotid artery phantom with a lipid area and obtained an image of the ultrasonic velocity change in the fatty area.

Mathematical modeling and simulation of the evolution of plaques in blood vessels

In this paper, a model is developed for the evolution of plaques in arteries, which is one of the main causes for the blockage of blood flow. Plaque rupture and spread of torn-off material may cause closures in the down-stream vessel system and lead to ischemic brain or myocardial infarctions. The model covers the flow of blood and its interaction with the vessel wall. It is based on the assumption that the penetration of monocytes from the blood flow into the vessel wall, and the accumulation of foam cells increasing the volume, are main factors for the growth of plaques. The dynamics of the vessel wall is governed by a deformation gradient, which is given as composition of a purely elastic tensor, and a tensor modeling the biologically caused volume growth. An equation for the evolution of the metric is derived quantifying the changing geometry of the vessel wall. To calculate numerically the solutions of the arising free boundary problem, the model system of partial differential equations is transformed to an ALE (Arbitrary Lagrangian-Eulerian) formulation, where all equations are given in fixed domains. The numerical calculations are using newly developed algorithms for ALE systems. The results of the simulations, obtained for realistic system parameters, are in good qualitative agreement with observations. They demonstrate that the basic modeling assumption can be justified. The increase of stresses in the vessel wall can be computed. Medical treatment tries to prevent critical stress values, which may cause plaque rupture and its consequences.

Basic study for diagnosing blood vessel plaque employing ultrasonic velocity-change imaging in combination with near-infrared illumination

It is important to detect unstable blood vessel plaques at an early stage to prevent their detachment and subsequent myocardial or brain infarctions. The instability of such plaques depends on the size and distribution of the internal lipid core. We propose a method for identifying lipid domains by changes in the ultrasound propagation velocity after warming with a near-infrared laser. First, we demonstrate that the most effective warming of fatty tissue to induce ultrasonic velocity changes is with a 935-nm laser. Next, a compliant blood vessel phantom containing an internal lipid domain was constructed and attached to a pulsatile pump. Experiments showed that the lipid domain could be identified with ultrasonic velocity-change imaging even in the presence of flow pulsation. We submit that ultrasonic velocity-change imaging under optical illumination may be an effective technique for diagnosing the presence of blood vessel plaques.

Detection and imaging of fatty plaques in blood vessels using functionalized carbon dots

Lighting the killer deposits on arterial walls: digitonin conjugated carbon dots enable the fluorescence imaging of cholesterol deposits in biological tissues.

Stability analysis of a model of atherosclerotic plaque growth.

Atherosclerosis, the formation of life-threatening plaques in blood vessels, is a form of cardiovascular disease. In this paper, we analyze a simplified model of plaque growth to derive physically meaningful results about the growth of plaques. In particular, the main results of this paper are two conditions, which express that the immune response increases as LDL cholesterol levels increase and that diffusion prevails over inflammation in a healthy artery.

In brief

PAGE 76 Research from the US and Japan presents a span power management scheme that aims to reduce the waiting time when activating lightpaths. The scheme makes use of stand-by dummy wavelength signals whose power can be rapidly decreased to compensate for the additional power required by the newly added lightpath, so that activation time can be significantly reduced. PAGE 80 In work from Belgium, researchers describe a latching MEMS switch, which uses a compact configuration of thermal actuators. Their mechanism allows reduction of required displacement of one of the contacts, enabling the use of a linear thermal actuator, resulting in a much more compact switch with a large contact force. The switch is designed for a bistable switch matrix in distribution frames or street cabinets in telecommunication access networks. The span power management scheme allows reduced waiting time in lightpath activation PAGE 108 Studies of the electrical characteristics of 650V GaN-on-silicon transistors in floating substrate condition configurations are reported in work from the UK and Japan. Results suggest that substrate potential is a critical parameter that can affect device characteristics and that floating the substrate needs to be carefully evaluated to ensure reliable operation of such transistors in power electronic circuits. The structure of the latching switch allows for a more compact switch with high contact force PAGE 83 A compact pulse laser source that efficiently generates high-power, short laser pulses is presented in work from Germany. Thanks to the nanosecond electronic driver developed for this work, based on GaN transistors and controlled by transistor-transistor logic compatible input pulses, the 920 nm source achieves output energy of 13 µJ with better than 50% electrical efficiency. Substrate potential can be a critical parameter for characteristics of GaN-on-silicon transistors PAGE 16 Ultrasonic (US) velocity-change imaging characterisation of carotid artery plaques is investigated in work from Japan. Using a blood vessel US phantom based model, researchers show that US velocity-change imaging can clearly identify lipid-rich areas. As the instability of blood vessel plaque is thought to be related to the size and distribution of the lipid core, the researchers believe this has application for non-invasive early detection of unstable carotid artery plaques. 50 ns optical pulses with 250 W peak power can be efficiently generated at 920 nm Ultrasonic velocity change images clearly show lipid rich areas

GW24-e3519 The study of atherosclerosis model in the rabbits fed with atherogenic diet

ObjectivesTo establish an atherosclerosis animal mode in the rabbit fed by atherogenic diet, and to observe the effects of atherogenic diet on rabbits’ body weight, mortality rate, blood lipids and...

Flow observations in elastic stenosis biomodel with comparison to rigid-like model

Plaques in blood vessels exhibit a wide range of stiffness depending on disease conditions: stiffness is an important factor in plaque behavior. The geometrical change in plaque based on its behavior can affect blood flow patterns. Thus, it is important to study both blood flow and deformation of plaques and blood vessels. This study aims to identify the differences in flow conditions between in vitro models to discuss experimental materials for arterial wall and flow observation. In order to observe the blood flow pattern and plaque deformation simultaneously, a PVA-H stenosis model was used. In addition, a silicone model was also used as a rigid-like model for comparison with the PVA-H model. PIV was employed to measure the flow velocity distribution and determine the flow levels in the models. PVA-H model exhibits expansion with an increase in upstream pressure and silicone model maintains the diameter. The expansion depends on their mechanical properties and influences flow conditions such as velocity changes and RAP in the parent artery. The balance between the expansion and change in flow conditions determines the final geometries of PVA-H model and flow pattern. The results suggest that the stiffness measurement for blood vessels and plaques such as ultrasound measurements would be important for accurate treatments.

A Biomimetic Active Electrolocation Sensor for Detection of Atherosclerotic Lesions in Blood Vessels

Weakly electric fish sense their surroundings in complete darkness by active electrolocation. In a biomimetic approach, we designed catheter-based technical sensor systems working according to the same biological principles that could be used for medical diagnostics of arteriosclerosis. Several measurements using artificial blood vessels, computer simulations, and a physical test bed showed that it is possible to detect and analyze vulnerable plaques in blood vessels and that our method of signal production and analysis is principally suitable for medical diagnostics.

Ka Sing Lawrence Wong: unlocking the causes of stroke in Asia

Ka Sing Lawrence Wong: unlocking the causes of stroke in Asia