Effect of LDL Extracted from Human Plasma on Membrane Stiffness in Living Endothelial Cells and Macrophages via Scanning Ion Conductance Microscopy

Mechanical properties of living cells play a crucial role in a wide range of biological functions and pathologies, including atherosclerosis. We used low-stress Scanning Ion-Conductance Microscopy (SICM) correlated with confocal imaging and demonstrated the topographical changes and mechanical properties alterations in EA.hy926 and THP-1 exposed to LDL extracted from CVD patients' blood samples. We show that the cells stiffened in the presence of LDL, which also triggered caveolae formation. Endothelial cells accumulated less cholesterol in the form of lipid droplets in comparison to THP-1 cells based on fluorescence intensity data and biochemical analysis; however, the effect on Young's modulus is higher. The cell stiffness is closely connected to the distribution of lipid droplets along the z-axis. In conclusion, we show that the sensitivity of endothelial cells to LDL is higher compared to that of THP-1, triggering changes in the cytoskeleton and membrane stiffness which may result in the increased permeability of the intima layer due to loss of intercellular connections and adhesion.

Ultrasound imaging of the dorsalis pedis artery as an early indicator of the precursory changes for rheumatoid vasculitis: A case series

Introduction

Clinical verification of rheumatoid vasculitis (RV) persists as a mid-to-late diagnosis with medical imaging or biopsy. Early and subclinical presentations of RV, in particular, can remain underdiagnosed in the absence of adequate diagnostic testing. In this study, the research demonstrated the precursory changes for RV in patients with rheumatoid arthritis (RA) using non-invasive ultrasound imaging of a peripheral vessel.

Method

Six participants were recruited: three participants with (RA) and three age- and gender-matched healthy controls. All participants completed a Foot Health Survey Questionnaire (FHSQ), and participants with RA completed a Rheumatoid Arthritis Disease Activity Index-5 (RADAI-5). Bilateral B-mode and Doppler ultrasound of the dorsalis pedis artery (DPA) was performed. The degree of inflammation, lumen and artery diameters, lumen diameter-to-artery diameter ratio and peak systolic velocity in the proximal DPA were compared between the two groups.

Results

The mean RADAI-5 score (5.4 ± 0.8 out of 10) indicated moderate disease activity amongst participants with RA. Inflammation was observed in the DPA wall in all participants with RA, compared to no inflammation observed in the control group (Friedmans two-way analysis: χ2 = 15.733, P = 0.003). Differences between groups for inflammation, lumen diameter and lumen diameter-to-artery diameter ratio were found (P < 0.034), without differences for artery diameter and peak systolic velocity (P > 0.605). DPA wall inflammation did not correlate with FHSQ scores (r = -0.770, P = 0.073).

Conclusion

Despite moderate RA disease activity, this is the first study to demonstrate the use of ultrasound to observe inflammation in small vessel disease. Our findings suggest ultrasound imaging may be a viable screening tool to demonstrate arterial wall inflammation, indicating the precursory changes of RV.

Review of the Protective Mechanism of Curcumin on Cardiovascular Disease

Cardiovascular diseases (CVDs) are the most common cause of death worldwide and has been the focus of research in the medical community. Curcumin is a polyphenolic compound extracted from the root of turmeric. Curcumin has been shown to have a variety of pharmacological properties over the past decades. Curcumin can significantly protect cardiomyocyte injury after ischemia and hypoxia, inhibit myocardial hypertrophy and fibrosis, improve ventricular remodeling, reduce drug-induced myocardial injury, improve diabetic cardiomyopathy(DCM), alleviate vascular endothelial dysfunction, inhibit foam cell formation, and reduce vascular smooth muscle cells(VSMCs) proliferation. Clinical studies have shown that curcumin has a protective effect on blood vessels. Toxicological studies have shown that curcumin is safe. But high doses of curcumin also have some side effects, such as liver damage and defects in embryonic heart development. This article reviews the mechanism of curcumin intervention on CVDs in recent years, in order to provide reference for the development of new drugs in the future.

Knickkopf (LmKnk) is required for chitin organization in the foregut of Locusta migratoria

The foregut, located at the front of the digestive tract, serves a vital role in insects by storing and grinding food into small particles. The innermost layer of the foregut known as the chitinous intima, comes into direct contact with the food and acts as a protective barrier against abrasive particles. Knickkopf (Knk) is required for chitin organization in the chitinous exoskeleton, tracheae and wings. Despite its significance, little is known about the biological function of Knk in the foregut. In this study, we found that LmKnk was stably expressed in the foregut, and highly expressed before molting in Locusta migratoria. To ascertain the biological function of LmKnk in the foregut, we synthesized specific double-stranded LmKnk (dsLmKnk) and injected it into locusts. Our findings showed a significant decrease in the foregut size, along with reduced food intake and accumulation of residues in the foregut after dsLmKnk injection. Morphological observations revealed that newly formed intima became thinner and lacked chitin lamella. Furthermore, fluorescence immunohistochemistry revealed that LmKnk was located in the apical region of new intima and epithelial cells. Taken together, this study provides insights into the biological function of LmKnk in the foregut, and identifies the potential target gene for exploring biological pest management strategies.

Spontaneous coronary artery dissection: an overview

The prevalence of spontaneous coronary artery dissection (SCAD) has increased over the last decades in young adults presenting with acute coronary syndrome. Although the diagnostic tools, including intracoronary imaging, have permitted a more accurate diagnosis of SCAD, the prognosis and overall outcomes remain dismal. Furthermore, the disproportionate sex distribution affecting more women and the underdiagnosis in many parts of the world render this pathology a persistent clinical challenge, particularly since the management remains largely supportive with a limited and controversial role for percutaneous or surgical interventions. The purpose of this review is to summarize the available literature on SCAD and to provide insights into the gaps in knowledge and areas requiring further investigation.

Constructing Lipoparticles Capable of Endothelial Cell-Derived Exosome-Mediated Delivery of Anti-miR-33a-5p to Cultured Macrophages

Atherosclerosis is driven by intimal arterial macrophages accumulating cholesterol. Atherosclerosis also predominantly occurs in areas consisting of proinflammatory arterial endothelial cells. At time of writing, there are no available clinical treatments that precisely remove excess cholesterol from lipid-laden intimal arterial macrophages. Delivery of anti-miR-33a-5p to macrophages has been shown to increase apoAI-mediated cholesterol efflux via ABCA1 upregulation but delivering transgenes to intimal arterial macrophages is challenging due to endothelial cell barrier integrity. In this study, we aimed to test whether lipoparticles targeting proinflammatory endothelial cells can participate in endothelial cell-derived exosome exploitation to facilitate exosome-mediated transgene delivery to macrophages. We constructed lipoparticles that precisely target the proinflammatory endothelium and contain a plasmid that expresses XMOTIF-tagged anti-miR-33a-5p (LP-pXMoAntimiR33a5p), as XMOTIF-tagged small RNA demonstrates the capacity to be selectively shuttled into exosomes. The cultured cells used in our study were immortalized mouse aortic endothelial cells (iMAECs) and RAW 264.7 macrophages. From our results, we observed a significant decrease in miR-33a-5p expression in macrophages treated with exosomes released basolaterally by LPS-challenged iMAECs incubated with LP-pXMoAntimiR33a5p when compared to control macrophages. This decrease in miR-33a-5p expression in the treated macrophages caused ABCA1 upregulation as determined by a significant increase in ABCA1 protein expression in the treated macrophages when compared to the macrophage control group. The increase in ABCA1 protein also simulated ABCA1-dependent cholesterol efflux in treated macrophages-as we observed a significant increase in apoAI-mediated cholesterol efflux-when compared to the control group of macrophages. Based on these findings, strategies that involve combining proinflammatory-targeting lipoparticles and exploitation of endothelial cell-derived exosomes appear to be promising approaches for delivering atheroprotective transgenes to lipid-laden arterial intimal macrophages.

Morphological Features of the Ascending Aorta Remodeling and Activation of Regeneratory Potential in Intima when Forming Aneurysm

In patients with an ascending aorta aneurysm, restructuring of all its layers and, first of all, the intima and media was revealed. The thickness of the intima was 79.3±63.1 μm in patients with aortic diameter <55 mm (group Ao<55) and 162.7±177.4 μm (p<0.05) in patients with aortic diameter ⩾55 mm (Ao⩾55 group), the thickness of the aortic media was 1184.0±198.2 and 1144.3±288.4 μm, respectively. In patients of the Ao<55 group, aortic dilatation was accompanied by compensatory thickening of the inner and middle layers of the aorta. In the Ao⩾55 group, thinning of the aortic media, fragmentation of elastic fibers, and its cystic degeneration were revealed. c-kit⁺ Stem cells were detected in the subendothelium of the thickened intima of the dilated ascending aorta. The appearance of c-kit⁺ cells correlated with intimal remodeling and its colonization with CD34⁺ and CD44⁺ myofibroblast-like cells.

Pulmonary Vascular Remodeling in Pulmonary Hypertension

Pulmonary vascular remodeling is the critical structural alteration and pathological feature in pulmonary hypertension (PH) and involves changes in the intima, media and adventitia. Pulmonary vascular remodeling consists of the proliferation and phenotypic transformation of pulmonary artery endothelial cells (PAECs) and pulmonary artery smooth muscle cells (PASMCs) of the middle membranous pulmonary artery, as well as complex interactions involving external layer pulmonary artery fibroblasts (PAFs) and extracellular matrix (ECM). Inflammatory mechanisms, apoptosis and other factors in the vascular wall are influenced by different mechanisms that likely act in concert to drive disease progression. This article reviews these pathological changes and highlights some pathogenetic mechanisms involved in the remodeling process.

Are acute type A aortic dissections atherosclerotic?

Background

Type A aortic dissections (TAAD) are devastating aortic complications. Patients with Marfan syndrome, a bicuspid aortic valve or a thoracic aortic aneurysm have an increased risk to develop a TAAD. These predisposing conditions are characterized by a histologically thin intimal layer and hardly any atherosclerosis. Little is known about the susceptibility for atherosclerosis in patients with a type A aortic dissection.

Objective

We aim to systematically describe atherosclerotic lesions in TAAD patients.

Materials and methods

A total of 51 patients with a TAAD (mean age 62.5 ± 10.8 years, 49% females) and 17 control patients (mean age 63 ± 5.5 years, 53% females) were included in this study. Cardiovascular risk factors were assessed clinically. All sections were stained with Movat pentachrome and hematoxylin eosin. Plaque morphology was classified according to the modified AHA classification scheme proposed by Virmani et al.

Results

In the TAAD group thirty-seven percent were overweight (BMI > 25). Diabetes and peripheral arterial disease were not present in any of the patients. Fifty-nine percent of the patients had a history of hypertension. The intima in TAAD patients was significantly thinner as compared to the control group (mean thickness 143 ± 126.5 μm versus 193 ± 132 μm, p < 0.023). Seven TAAD patients had a normal intima without any form of adaptive or pathological thickening. Twenty-three TAAD patients demonstrated adaptive intimal thickening. Fourteen had an intimal xanthoma, also known as fatty streaks. A minority of 7 TAAD patients had progressive atherosclerotic lesions, 4 of which demonstrated pathological intimal thickening, 3 patients showed early fibroatheroma, late fibroatheroma and thin cap fibroatheroma. In the control group the majority of the patients exhibited progressive atherosclerotic lesions: three pathologic intimal thickening, two early fibroatheroma, six late fibroatheroma, one healed rupture and two fibrotic calcified plaque.

Discussion

This study shows that TAAD patients hardly exhibit any form of progressive atherosclerosis. The majority of TAAD patients showcase non-progressive intimal lesions, whereas the control group mostly demonstrated progressive intimal atherosclerotic lesions. Findings are independent of age, sex, or the presence of (a history of) hypertension.

Insufficient development of vessels and alveoli in lungs of infants with trisomy 18-Features of pulmonary histopathological findings from lung biopsy

The aim of this study was to evaluate the features of pulmonary histopathological changes in cases of trisomy 18 complicated with congenital heart disease and pulmonary arterial hypertension. Twenty-eight patients with trisomy 18 underwent open lung biopsy at the time of primary operation in our hospital between 2008 and 2019. We compared these histopathological findings with those from previously described groups without trisomy 18. Mean age at primary cardiac surgery was 37 days (range, 9-69 days). According to the Heath-Edwards (HE) classification, 1, 8, 12, and 5 patients were graded as 0, 1, 2, and 3, respectively, whereas 2 patients were not classifiable due to medial defects in the small pulmonary arteries (MD). Four (14.3%) and 13 (46.4%) patients presented with MD and hypoplasia of the small pulmonary arteries (HS). Fifteen (53.6%) and 21 (75.0%) patients presented with alveolar hypoplasia (AH) and alveolar wall thickening (AT). MD, HS, and AH in trisomy 18 were present frequently, differing significantly from previous reports. These findings might be associated with congenital inadequate development of vessels and alveoli in the lung, contributing to a high risk of PAH in trisomy 18.

Connexin43 is differentially distributed within renal vasculature and mediates profibrotic differentiation in medullary fibroblasts

Connexins (Cxs) form gap junctions for intercellular exchange of inorganic ions and messenger molecules. In the kidney, Cxs play essential roles within its compartments, but data on the precise cellular localization and cell type-related function of their isoforms are scarce. We tested whether Cx43 distribution is restricted to vascular and interstitial cells and whether medullary fibroblasts express Cx43 to coordinate profibrotic signaling. Confocal immunofluorescence techniques, ultrastructural labeling, and functional experiments in cell culture were performed. Cx43 was chiefly expressed in the vasculature but was absent from tubular epithelia. All arterial, arteriolar, and lymphatic endothelia showed continuous Cx43 signal along their borders. In the inner medulla, only the interstitium showed Cx43 signals, which were assigned to fibroblasts and their processes. Cultured Cx43-expressing medullary fibroblasts served to study the role of gap junctions in a profibrotic context. In a dye spreading assay, Cx43-sensitive diffusion of Lucifer yellow was dependent on gap junctional passage. The addition of transforming growth factor-β1 (5 ng/mL for 48 h) activated Cx43 biosynthesis and caused Cx43-sensitive transformation of the fibroblasts into a myofibroblast phenotype. This suggested that Cx43 gap junctional channels enable the coordination of profibrotic signaling between cells of the medullary interstitium. In summary, we demonstrate the presence of Cx43-expressing gap junctions within the two major renal compartments, the vasculature and interstitium. Endothelial Cx43 likely provides functions of an earlier-defined "electrical syncytium" within the vascular wall. Additionally, Cx43 facilitates profibrotic signaling between medullary interstitial fibroblasts.

The effects of glycaemic variability on intimal hyperplasia and plaque stability after stenting via autophagy-mediated G3BP1/NLRP3 inflammasome

Background

The objective of this study was to investigate the effects of glycaemic variability (GV) on intimal hyperplasia and plaque stability after coronary stenting via autophagy-mediated G3BP1/NLRP3 inflammasome signalling.

Methods

In the clinical study, between July 2017 and December 2017, 95 patients with acute myocardial infarction (AMI) and diabetes mellitus (DM) comorbidity received stent implantation. The patients were followed up for 2 years after discharge. The patients were divided into a low-GV (n=61) and high-GV (n=34) group, and the incidence of recurrent AMI was measured. In the animal study, thirteen pigs were divided into a sham (n=3), low-GV DM (n=5) and high-GV DM group (n=5). Intima samples were analysed by optical coherence tomography 22 weeks after coronary stenting. Becn1, LC3B, p62, G3BP1 and NLRP3 protein levels in the intima were examined by western blot. In vitro experiments with THP-1 cells were also conducted.

Results

In the high-GV group, patients exhibited a higher recurrent AMI, greater neointimal thickness, increased p62 and NLRP3 expression, and decreased Becn1, LC3B and G3BP1 expression compared with the low-GV group (P<0.05). The effects of high GV could be abolished by rapamycin but were aggravated by 3-methyladenine.

Conclusions

GV might impact the intimal hyperplasia and plaque stability via autophagy-mediated G3BP1/NLRP3 inflammasome signalling. GV and the autophagy-mediated G3BP1/NLRP3 inflammasome may be promising targets for the treatment of coronary heart disease.

Possible Roles of Periostin in the Formation of Hemodialysis Vascular Access Stenosis after Polytetrafluoroethylene Graft Implantation in Dogs

Periostin, a recently found matricellular protein, has been implicated in neointima formation after balloon injury. However, the relationship between periostin and hyperplastic intima formation after PTFE graft implantation is unclear. Under mixed anesthesia, PTFE grafts were implanted between the canine carotid artery and jugular vein, and PTFE graft samples were harvested 1, 2, and 4 months after implantation. Intima formation started on the luminal surface of PTFE grafts at the venous anastomotic region 1 month after implantation. Thereafter, the increase in intimal volume was not only observed in the venous and arterial anastomotic regions, but also in the middle region of the PTFE grafts. In accordance with the increased intimal formation, time-dependent increases in mRNA expressions of periostin and transforming growth factor beta 1 (TGF-β1), as well as a strong positive correlation between periostin and TGF-β1, were observed. These findings suggest that periostin may play a very important role in the pathogenesis of hemodialysis vascular access stenosis through the acceleration of intimal formation. Thus, periostin may be a very important therapeutic target for the treatment of vascular access graft dysfunction in hemodialysis patients.

[Atherosclerosis and atheromatosis are consequtive metabolic disordes. Pathology of the biological functions of trophology and endoecology is the basis for ischemic heart disease prevention.]

Atherosclerosis and atheromatosis are different nonphysiological processes with different etiology and pathogenesis. They manifest alterations in different biological functions. According to our original phylogenetic theory of general pathology, atherosclerosis is associated with altered biological function of trophology, eating, biological reaction of exotrophy. Atherosclerosis is induced by eating of nonoptimal for phylogenetically herbivorous Homo sapiens meat diet with high content of palmitic saturated fatty acid (SFA), which leads to in vivo formation of phylogenetically early low-efficient palmitic pathway of FA metabolism instead of highly-efficient oleic pathway operating in herbivores. Accumulation of nonligand palmitic very low density lipoproteins (VLDL) and low density lipoproteins (LDL) in the bloodstream results from nonphysiological reaction of compensation upon transport of palmitic SFA to cells. An increase in blood content of palmitic triglycerides (TG) and nonligand palmitic VLDLЛ→LDL coincides with the development of hypercholesterolemia: type IV→ type IIb → type V. Atheromatosis compensates changes in lipoproteins by activation of the biological function of endoecology (purity of the extracellular medium) in vivo, thus fulfilling the biological reaction of inflammation. This is physiological denaturation of apoВ-100 in nonligand VLDL→LDL by neutrophils via peroxidation, opsonization by the complement components, transcytosis across the endothelial monolayer and removal to the intima of elastic arteries that serves as a collection and utilization pool for phogogens from local intravascular pool of the intercellular medium. Endogenous phlogogens are utilized by phylogenetically early polyfunctional resident macrophages which are small in number and do not proliferate. Blood-borne monocytes-macrophages are also involved in this process, however, they do not express acid hydrolase of polyenic cholesteryl esters. Atheromatous masses are partially catabolized polyenic FA esterified by the alcohol cholesterol which were not internalized by cells. Atheromatosis is a process of pathological compensation in the realization of the function of endoecology. Prevention of atherosclerosis and atheromatosis should be based on elimination of the effects produced by a nonphysiological meat diet.

Location of Dissections Post Balloon Angioplasty in Patients With Femoropopliteal Arterial Disease as Seen on Intravascular Ultrasound

We reviewed images from our intravascular ultrasound core lab to define the various locations of dissections in femoropopliteal arteries post balloon angioplasty in relation to plaque morphology.

Trained Circulating Monocytes in Atherosclerosis: Ex Vivo Model Approach

Inflammation is one of the key processes in the pathogenesis of atherosclerosis. Numerous studies are focused on the local inflammatory processes associated with atherosclerotic plaque initiation and progression. However, changes in the activation state of circulating monocytes, the main components of the innate immunity, may precede the local events. In this article, we discuss tolerance, which results in decreased ability of monocytes to be activated by pathogens and other stimuli, and training, the ability of monocyte to potentiate the response to pathological stimuli, and their relation to atherosclerosis. We also present previously unpublished results of the experiments that our group performed with monocytes/macrophages isolated from atherosclerosis patients. Our data allow assuming the existence of relationship between the formation of monocyte training and the degree of atherosclerosis progression. The suppression of trained immunity ex vivo seems to be a perspective model for searching anti-atherogenic drugs.

Vascular Smooth Muscle Cells Contribute to Atherosclerosis Immunity

Vascular smooth muscle cells (VSMCs) constitute the major cells in the media layer of arteries, and are critical to maintain the integrity of the arterial wall. They participate in arterial wall remodeling, and play important roles in atherosclerosis throughout all stages of the disease. Studies demonstrate that VSMCs can adopt numerous phenotypes depending on inputs from endothelial cells (ECs) of the intima, resident cells of the adventitia, circulating immune cells, hormones, and plasma lipoproteins. This plasticity allows them to perform multiple tasks in physiology and disease. In this minireview, we focus on a previously underappreciated activity of VSMCs, i.e., their impact on atherosclerosis immunity via formation of artery tertiary lymphoid organs (ATLOs).

Some segmental morphological and morphometrical features of the intima and media of the aortic wall in Chinchilla lanigera

BACKGROUND

The aim of this study is to describe the morphology, morphometry and ultrastructure of segments of the thoracic and abdominal aorta portions in Chinchilla lanigera. Thickness measurements of the tunica intima and media complex of the aorta were taken.

MATERIALS AND METHODS

In all observed specimens, the thickness values for the tunica intima and media complex of the cranial thoracic aorta were significantly higher (mean: 702.19 μm) when compared to the values of other analysed aortic segments (means: 354.18 μm; 243.55 μm). Complex statistical methods were used to assess the differences between various aortic segments.

RESULTS AND CONCLUSIONS

The components of the vessel walls show variations in structure and thickness, presumably due to an adaptation to functional demand.

[Biological function of endoecology (cleanliness of intercellular environment) realize two biolocical reactions: excretion reaction and inflammation reaction - utilization in vivo, in situ catabolites of the large molecular mass.]

For the biological functions of trophology (nutrition) and homeostasis, we believe that the third place is occupied by the function of endoecology: in a single pool of intercellular environment in vivo it must be "pure". The biological function of endoecology, realizes two biological reactions: the reaction of excretion and the reaction of inflammation. The biological reaction of excretion is the filtration of phlogogens of a small mol. mass through the basement membrane of the glomerulus of the nephron and excretion with the final urine. Flogogens are a great mol. mass (more than 70 kDa), catabolites of biological reactions of apoptosis, autophagy must be disposed of in situ, on site. At the stages of phylogenesis, the cells formed structures for the collection and utilization of phlogogens of large mol. mass and exogenous pathogens in tissues. The sequence of biochemical reactions, biological methods of in vivo collection and in situ utilization of phlogogens of large mol. mass and realizes the biological function of endoecology, the biological reaction of inflammation. It functions constantly, every minute, like the biological reaction of excretion. Inflammation is the reaction of maintaining the "cleanliness" of the "piece" of the ocean that every individual has privatized, before beginning to live on land. The inflammation reaction includes congenital, acquired immunity, humoral mediator systems, cytokines and eicosanoids. In the formation of a closed circulatory system, the pool for collecting and utilizing in situ biological catabolites from the bloodstream is located in the late phylogeny of the intima of the arteries of the elastic (muscular-elastic) type. Abuse of herbivorous species Homo sapiens carnivorous (meat) food; blockade of cellular absorption by polyene fatty acids in low density lipoproteins and the absence of acidic hydrolase expression of polyene fatty acids - cholesterol alcohol ethers in monocytes and macrophages - is the cause of the formation of atheroma of intima of the arteries of the elastic type. Atherosclerosis - the pathology of the biological function of trophology, atheromatosis - pathology of the biological function of endoecology. The appointment of patients statins for primary prevention of atherosclerosis, atheromatosis and coronary heart disease, we finally "passed".

Intimal and medial contributions to the hydraulic resistance of the arterial wall at different pressures: a combined computational and experimental study

The hydraulic resistances of the intima and media determine water flux and the advection of macromolecules into and across the arterial wall. Despite several experimental and computational studies, these transport processes and their dependence on transmural pressure remain incompletely understood. Here, we use a combination of experimental and computational methods to ascertain how the hydraulic permeability of the rat abdominal aorta depends on these two layers and how it is affected by structural rearrangement of the media under pressure. Ex vivo experiments determined the conductance of the whole wall, the thickness of the media and the geometry of medial smooth muscle cells (SMCs) and extracellular matrix (ECM). Numerical methods were used to compute water flux through the media. Intimal values were obtained by subtraction. A mechanism was identified that modulates pressure-induced changes in medial transport properties: compaction of the ECM leading to spatial reorganization of SMCs. This is summarized in an empirical constitutive law for permeability and volumetric strain. It led to the physiologically interesting observation that, as a consequence of the changes in medial microstructure, the relative contributions of the intima and media to the hydraulic resistance of the wall depend on the applied pressure; medial resistance dominated at pressures above approximately 93 mmHg in this vessel.

The Carotid Intima-Media Thickness and Arterial Stiffness of Pediatric Mucopolysaccharidosis Patients Are Increased Compared to Both Pediatric and Adult Controls

Treatments for mucopolysaccharidoses (MPSs) have increased longevity, but cardiovascular disease causes mortality in a significant percentage of survivors. Markers must be developed to predict MPS cardiac risk and monitor efficacy of investigational therapies.MPS patients underwent carotid artery ultrasonography from which carotid intima-media thickness (cIMT) and three measures of arterial stiffness were calculated: carotid artery distensibility (cCSD), compliance (cCSC), and incremental elastic modulus (cIEM). MPS carotid measurements were compared to corresponding data from pediatric and adult healthy cohorts. 33 MPS patients (17 MPS I, 9 MPS II, 4 MPS IIIA, and 3 MPS VI; mean age 12.5 ± 4.7 years), 560 pediatric controls (age 13.1 ± 4.0 years), and 554 adult controls (age 39.2 ± 2.2 years) were studied. Age and sex-adjusted aggregate MPS cIMT (0.56 ± 0.05 mm) was significantly greater than both pediatric (+0.12 mm; 95% CI +0.10 to +0.14 mm) and adult (+0.10 mm; 95% CI +0.06 to +0.14 mm) control cohorts; similar findings were observed for all MPS subtypes. Mean MPS cIMT approximated the 80th percentile of the adult cohort cIMT. MPS patients also demonstrated significantly increased adjusted arterial stiffness measurements, evidenced by reduced cCSD, cCSC, and increased cIEM, compared to pediatric and adult control cohorts. Regardless of treatment, MPS patients demonstrate increased cIMT and arterial stiffness compared to healthy pediatric and adult controls. These data suggest that relatively young MPS patients demonstrate a “structural vascular age” of at least 40 years old.

[The individual fatty acids of blood plasma: biological role of substrates, parameters of quantity and quality, diagnostic of atherosclerosis and atheromotosis.]

The atherosclerosis and atheromotosis are supposed to be, according to phylogenetic theory of general pathology, two etiologically different aphysiological processes, unified by community of pathogenesis. The atherosclerosis is a derangement of biological function of trophology (feeding), biological reaction of exotrophy (external feeding) and biological function of adaptation, biological reaction of compensation in response to deficiency of ῳ-3 and ῳ-6 polyenoic fatty acids. In case of deficiency of polyenoic fatty acids in cells and during synthesis of eicosanoids of group I from unsaturated endogenous ῳ-6 С20: 3 digomo-γ-linoleic unsaturated fatty acid, atherosclerosis is developed, a complex metabolism disorder in vivo. The atheromotosis is a derangement of biological function of endoecology, biological reactions of inflammation and inherent immunity. This incomplete utilization in intima of arteries of non-ligand palmitic lipoproteins of very low → low density under effect not of polyfunctional resident macrophage but monocytes of hematogenic origin without expression of acid hydrolase of polyenoic ethers of cholesterol. In intima, in area of cumulation of endogenous phlogogens (initiator of inflammation) from the pool of intra-vascular medium, polyenoic unsaturated fatty acids are cumulated that were not absorbed by cells in structure of ligand low density palmitic lipoproteins using apoB-100- endocytosis. The pathogenic factor of atherosclerosis - derangement of biological function of trophology. biological function of exotrophy under alimentary deficiency of in vivo of ῳ-3 and ῳ-6 polyenoic fatty acids with physiological parameters of feeding. The pathogenic factor of atheromotosis - phylogenetically herbivorous (carnivorous) human misusing of animal (meat) food, palmitic unsaturated fatty acids, development by hepatocytes of a large number of palmitic triglycerides and lipoproteins of very low density of the same name. The late in phylogenesis insulin-dependent lipoproteins of very low density transfer palmitic lipoproteins of very low density to cells slowly. The cells absorb them also slowly. The cumulation of non-ligand palmitic lipoproteins of very low density → low density in blood competitively blocks physiological absorption of polyenoic unsaturated fatty acids by cells in structure of physiological palmitic lipoproteins of low density. The atherosclerosis occurs blood flow and atheromotosis in intima of arteries of elastic type.

Biophysical and Biochemical Outcomes of Chlamydia pneumoniae Infection Promotes Pro-atherogenic Matrix Microenvironment

Multiple studies support the hypothesis that infectious agents may be involved in the pathogenesis of atherosclerosis. Chlamydia pneumoniae is strongly implicated in atherosclerosis, but the precise role has been underestimated and poorly understood due to the complexity of the disease process. In this work, we test the hypothesis that C. pneumoniae-infected macrophages lodged in the subendothelial matrix contribute to atherogenesis through pro-inflammatory factors and by cell-matrix interactions. To test this hypothesis, we used a 3D infection model with freshly isolated PBMC infected with live C. pneumoniae and chlamydial antigens encapsulated in a collagen matrix, and analyzed the inflammatory responses over 7 days. We observed that infection significantly upregulates the secretion of cytokines TNF-α, IL-1β, IL-8, MCP-1, MMP, oxidative stress, transendothelial permeability, and LDL uptake. We also observed that infected macrophages form clusters, and substantially modify the microstructure and mechanical properties of the extracellular matrix to an atherogenic phenotype. Together, our data demonstrates that C. pneumoniae-infection drives a low-grade, sustained inflammation that may predispose in the transformation to atherosclerotic foci.

Attenuated-Signal Plaque Progression Predicts Long-Term Mortality After Heart Transplantation: IVUS Assessment of Cardiac Allograft Vasculopathy

BACKGROUND

Although cardiac allograft vasculopathy (CAV) is typically characterized by diffuse coronary intimal thickening with pathological vessel remodeling, plaque instability may also play an important role in CAV. Previous studies of native coronary atherosclerosis have demonstrated associations between attenuated-signal plaque (ASP), plaque instability, and adverse clinical events.

OBJECTIVES

This study's aim was to characterize the association between ASP and long-term mortality post-heart transplantation.

METHODS

In 105 heart transplant recipients, serial (baseline and 1-year post-transplant) intravascular ultrasound was performed in the first 50 mm of the left anterior descending artery. The ASP score was calculated by grading the measured angle of attenuation from grades 0 to 4 (specifically, 0°, 1° to 90°, 91° to 180°, 181° to 270°, and >270°) at 1-mm intervals. The primary endpoint was all-cause death or retransplantation.

RESULTS

At 1-year post-transplant, 10.5% of patients demonstrated ASP progression (newly developed or increased ASP). Patients with ASP progression had a higher incidence of acute cellular rejection during the first year (63.6% vs. 22.3%; p = 0.006) and tendency for greater intimal growth (percent intimal volume: 9.2 ± 9.3% vs. 4.4 ± 5.3%; p = 0.07) than those without. Over a median follow-up of 4.6 years, there was a significantly lower event-free survival rate in patients with ASP progression at 1-year post-transplant compared with those without. In contrast, maximum intimal thickness did not predict long-term mortality.

CONCLUSIONS

ASP progression appears to reflect chronic inflammation related to acute cellular rejection and is an independent predictor of long-term mortality after heart transplantation. Serial assessments of plaque instability may enhance identification of high-risk patients who may benefit from closer follow-up and targeted medical therapies.

[Pathophysiological mechanisms of vascular calcification]

Vascular calcification (VC) is a degenerative pathology of the vessel wall. In the general population, VC appearance is associated with aging, but this pathology can also develop as a consequence of atherosclerosis, diabetes, inflammatory and chronic kidney disease. VC is strongly associated with increased risk of mortality and cardiovascular disease. Although VC has long been considered as the result of a passive precipitation of mineral, it is now well established that this pathology results from an active and highly regulated cellular process, which shares similarities with bone formation. This review summarizes our current knowledge on VC formation, and details the modalities of action of the main actors known to modulate this process.

Effect of dyslipidemia on intima-media thickness of intra- and extracranial atherosclerosis by regulating the expression of hsp70 in rabbits

The aim of this study was to explore the effect of dyslipidemia on intima-media thickness (IMT) of Intra- and extracranial atherosclerosis by regulating the expression of heat shock protein 70 (HSP70) in rabbits. Twenty-seven male white rabbits were randomly divided into normal control group A, high fat group B and high fat + endothelial injury operation group C (each group was 9), we measured lipids and obtained tissues from different cerebral arteries including Bilateral common carotid artery (CCA), Internal carotid artery (ICA), middle cerebral artery (MCA) and vertebral artery (VA). Pathological analysis were done, western blot analysis was used to detect the expression of HSP70 in CCA and MCA. The Serum lipid levels were overall significantly increased at 12(th) week in Group B and Group C compared to normal control (P < 0.05); at 12(th) week, the IMT of CCA and MCA in group B and C were showed significant increment compared with Group A; the correlation between HDL/CHOL/LDL and IMT of different cerebral arteries are as follows: MCA > ICA > CCA > VA; between TG and IMT of different cerebral arteries: VA > ICA > MCA > CCA; the expression of HSP70 from MCA were increased compared with CCA in group B and group C (P < 0.05). Significant positive correlations were observed between hyperlipidemia and different cerebral arteries. Hyperlipidemia has more impact on IMT of intracranial cerebral arteries. The expression of HSP70 from intracranial cerebral arteries is significantly increased. The mechanisms underlied was speculated that might be involved in inhibiting the inflammatory via HSP70.

Quantitative Measurement of Dissection Resistance in Intimal and Medial Layers of Human Coronary Arteries

The left anterior descending (LAD) coronary artery is the most frequently involved vessel in coronary artery dissection, a cause of acute coronary syndrome or sudden cardiac death. The biomechanical mechanisms underlying arterial dissection are not well understood. This study investigated the dissection properties of LAD specimens harvested from explanted hearts at the time of cardiac transplantation, from patients with primary dilated cardiomyopathy (n=12). Using a previously validated approach uniquely modified for these human LAD specimens, we quantified the local energy release rate, G, within different arterial layers during experimental dissection events (tissue tearing). Results show that the mean values of G during arterial dissection within the intima and within the media in human LADs are 20.7±16.5 J/m² and 10.3±5.0 J/m², respectively. The difference in dissection resistance between tearing events occurring within the intima and within the media is statistically significant. Our data fall in the same order of magnitude as most previous measurements of adhesive strength in other human arteries, with the differences in measured values of G within the layers most likely due to histologically observed differences in the structure and composition of arterial layers.

Assessing vascular status and risk of latent ischemia with ankle fracture: a case report and algorithm for treatment

A paucity of published studies and clinical recommendations are available regarding ankle fracture and its association with vascular injury, likely because of the lower incidence relative to the more commonly seen popliteal artery injury after knee dislocation. In the present case report, we describe a previously healthy patient who experienced a pilon type ankle fracture (AO 43C2) with fibular and syndesmotic involvement, followed by a subacute presentation of vascular ischemia weeks after the initial injury and repair, ultimately leading to a major amputation. The failure to identify an occult, vascular injury can have devastating consequences. Guidelines regarding the identification and management of displaced ankle fracture-associated vascular injury, drawing evidence from other traumatic injury complexes, could improve the clinical outcomes. We aim to raise awareness of the association of vascular embarrassment secondary to ankle fracture by proposing a clinical practice algorithm to aid clinicians in recognizing traumatic vascular injury at the earliest and most treatable stage.

Nogo-B expression, in arterial intima, is impeded in the early stages of atherosclerosis in humans

Nogo-B (Reticulon 4B) is considered to be a novel vascular marker, which may have a protective role in injury-induced neointima formation and atherosclerosis. Nogo A/B is found to be crucial for monocyte/macrophage recruitment in acute inflammation and it is expressed in CD68 + macrophages. We hypothesize that macrophage infiltration in atherosclerosis is not dependent on Nogo-B expression in arterial wall. We have assessed Nogo-B expression and macrophage accumulation in the iliac arteries of healthy organ donors and organ donors with cardiovascular risk factors. Paraffin sections of 66 iliac arteries, from 44 deceased organ donors (17 women and 27 men), were studied. The healthy and cardiovascular risk (CVR) subgroups were created. With regard to staging of the atherosclerotic process, the thickness of arterial intima was measured in digitalized images of H+E stained tissue sections. Immunohistochemical reactions (Nogo-B and CD68) were carried out in all arteries (66 samples). Western blotting (WB-19 samples) and real-time PCR (27 samples) were performed on selected arteries. Significantly higher Nogo-B expression was demonstrated in the intima of the healthy subjects' subgroup, using immunohistochemistry. WB and real-time PCR revealed a trend toward lower Nogo-B expression in the adventitia of the CVR subgroup. Furthermore, the thickness of the intima was found to negatively correlate with the expression of Nogo-B in the intima and media (r = -0.32; p < 0.05; r = -0.32; p < 0.05). Macrophage infiltrates were more prominent in intima of CVR subjects (0.65 vs 3.52 a.u.; p < 0.01). Macrophage density in intima increased with atherosclerosis progression (r = 0.37; p < 0.01). CD68 macrophages density in adventitia was lower in CVR arteries than in healthy arteries. The expression of Nogo-B, in arterial intima, is impeded in the early stages of atherosclerosis. Accumulation of arterial intimal CD68 macrophages has been shown to progress; however, the overall macrophage density in the adventitia is reduced in arteries shown to have intimal thickening. Macrophage infiltration is not accompanied by Nogo-B expression in atherosclerotic arteries.

Ultrastructure Study of Transgenic Ren2 Rat Aorta - Part 1: Endothelium and Intima

BACKGROUND: The renin-angiotensin-aldosterone system plays an important role in the development and progression of hypertension and accelerated atherosclerosis (atheroscleropathy) associated with the cardiorenal metabolic syndrome and type 2 diabetes mellitus. Additionally, the renin-angiotensin-aldosterone system plays an important role in vascular-endothelial-intimal cellular and extracellular remodeling. METHODS: Thoracic aortas of young male transgenic heterozygous (mRen2)27 (Ren2) rats were utilized for this ultrastructural study. This lean model of hypertension, insulin resistance and oxidative stress harbors the mouse renin gene with increased local tissue (aortic) levels of angiotensin II and angiotensin type 1 receptors and elevated plasma aldosterone levels. RESULTS: The ultrastructural observations included marked endothelial cell retraction, separation, terminal nuclear lifting, adjacent duplication, apoptosis and a suggestion of endothelial progenitor cell attachment. The endothelium demonstrated increased caveolae, microparticles, depletion of Weibel-Palade bodies, loss of cell-cell and basal adhesion hemidesmosome-like structures, platelet adhesion and genesis of subendothelial neointima. CONCLUSION: These observational ultrastructural studies of the transgenic Ren2 vasculature provide an in-depth evaluation of early abnormal remodeling changes within conduit-elastic arteries under conditions of increased local levels of angiotensin II, oxidative stress, insulin resistance and hypertension.

Layer-dependent variation in the anisotropy of apparent integrated backscatter from human coronary arteries

Clinical imaging of the coronary arteries in the cardiac catheterization laboratory using intravascular ultrasound (IVUS) is known to display a three-layered appearance, corresponding to the intima/plaque, media and adventitia. It is not known whether ultrasonic anisotropy arising from these tissues may alter this pattern in future IVUS systems that insonify in the forward direction or obliquely. In anticipation of such devices, the current study was carried out by imaging fresh human coronary arteries in two orthogonal directions in vitro. Twenty-six sites from 12 arteries were imaged with a side-looking IVUS system, and with an acoustic microscope both radially and axially. Side-looking IVUS and radial acoustic microscopy scans demonstrated the typical "bright-dark-bright" pattern of the backscatter, with the media being significantly darker than the other two layers. Images obtained in the axial orientation exhibited a markedly different pattern, with the relative brightness of the media significantly larger than that of the intima/plaque.

Automated detection of the arterial inner walls of the common carotid artery based on dynamic B-mode signals

In this paper we propose a novel scheme able to automatically detect the intima and adventitia of both near and far walls of the common carotid artery in dynamic B-mode RF (radiofrequency) image sequences, with and without plaques. Via this automated system the lumen diameter changes along the heart cycle can be detected. Three image sequences have been tested and all results are compared to manual tracings made by two professional experts. The average errors for near and far wall detection are 0.058 mm and 0.067 mm, respectively. This system is able to analyze arterial plaques dynamically which is impossible to do manually due to the tremendous human workload involved.

Search for optimized conditions for sealing and storage of bypass vessels: influence of preservation solution and filling pressure on the degree of endothelialization

The aim of the present study was to develop methods for the rapid assessment of intimal quality of coronary bypass segments of venous origin, and to prevent endothelial damage by improved intraoperative handling of graft segments. Particular attention was paid to the influence of the composition of the preservation solution and the intravasal filling pressure on the degree of endothelialization. Intrava-sal exposure to Alcian blue at pH<3 resulted in highly specific staining of intimal regions with functionally or structurally damaged endothelium. Standardization of preparation, staining and image acquisition of the intimal surface of graft remnants and subsequent computer-aided planimetry of these images made it possible for the first time to perform rapid serial investigations for quality control of bypass grafts. Using saline as the rinsing and intraoperative storage medium resulted in the loss of more than 50% of the endothelium at intravasal pressures of 0-100 mmHg. Increasing the pressure resulted eventually in complete de-endothelialization. In contrast, grafts incubated in a customized plasma derivative tolerated pressures of up to 200 mmHg with no significant endothelial loss; and even after exposure to 1,000 mmHg (10 times the average mean arterial pressure!) more than 70% of the endothelium were intact and vital. These findings imply strongly that the quality of aortocoronary bypass grafts of venous origin can be improved substantially by the use of a plasma derivative solution for intraoperative preservation and by monitoring and controlling the intravasal pressures reached during sealing and storage.