Explore the value of carotid ultrasound radiomics nomogram in predicting ischemic stroke risk in patients with type 2 diabetes mellitus

Background and objective

Type 2 Diabetes Mellitus (T2DM) with insulin resistance (IR) is prone to damage the vascular endothelial, leading to the formation of vulnerable carotid plaques and increasing ischemic stroke (IS) risk. The purpose of this study is to develop a nomogram model based on carotid ultrasound radiomics for predicting IS risk in T2DM patients.

Methods

198 T2DM patients were enrolled and separated into study and control groups based on IS history. After manually delineating carotid plaque region of interest (ROI) from images, radiomics features were identified and selected using the least absolute shrinkage and selection operator (LASSO) regression to calculate the radiomics score (RS). A combinatorial logistic machine learning model and nomograms were created using RS and clinical features like the triglyceride-glucose index. The three models were assessed using area under curve (AUC) and decision curve analysis (DCA).

Results

Patients were divided into the training set and the testing set by the ratio of 0.7. 4 radiomics features were selected. RS and clinical variables were all statically significant in the training set and were used to create a combination model and a prediction nomogram. The combination model (radiomics + clinical nomogram) had the largest AUC in both the training set and the testing set (0.898 and 0.857), and DCA analysis showed that it had a higher overall net benefit compared to the other models.

Conclusions

This study created a carotid ultrasound radiomics machine-learning-based IS risk nomogram for T2DM patients with carotid plaques. Its diagnostic performance and clinical prediction capabilities enable accurate, convenient, and customized medical care.

Study on the Consistency of Angiogenesis in Carotid Plaque Evaluated by Contrast-Enhanced Ultrasound and Superb Microvascular Imaging and Its Correlation With Stroke Occurrence

OBJECTIVES

This study aimed to investigate the value of contrast-enhanced ultrasound (CEUS) and superb microvascular imaging (SMI) in evaluating angiogenesis in carotid artery plaques and prognosis in stroke patients.

METHODS

Sixty-one patients with carotid atherosclerotic plaques were selected. All patients received conventional ultrasound, CEUS, and SMI examination, including 32 patients with cerebral infarction and 29 patients without cerebral infarction. The results of CEUS and SMI neovascularization of patients were graded 0, 1, and 2 points according to the image characteristics. The consistency between SMI results and CEUS results was evaluated, and the differences in neovascularization in carotid plaques between patients with cerebral infarction and those without cerebral infarction were compared.

RESULTS

SMI showed that the neovascularization score in plaque was 0 point in 13 cases, 1 point in 24 cases, and 2 points in 24 cases. There were no significant differences in age, sex, plaque size, or echo between the two groups. There was no significant difference between the SMI and CEUS results, P > .05. The CEUS neovascularization grade of patients with cerebral infarction had a higher score, which was significantly different from that of patients without cerebral infarction, P < .05. The SMI neovascularization grade of patients with cerebral infarction had a higher score, which was significantly different from that of patients without cerebral infarction, P < .05.

CONCLUSION

SMI can show neovascularization in plaques, with a significantly higher grade of neovascularization in those of patients with cerebral infarction than in those without cerebral infarction.

Homocysteine Facilitates the Formation of Carotid Atherosclerotic Plaque Through Inflammatory and Noninflammatory Mechanisms

Background: Elevated homocysteine (Hcy) was considered a significant risk factor in the development and progression of carotid atherosclerosis (CAS), which involves a combination of inflammatory and noninflammatory mechanisms. However, epidemiological surveys have presented conflicting results. In this study, we aim to offer an epidemiological viewpoint on how elevated Hcy impacts CAS and its potential mechanisms. Methods: Levels of high-sensitivity C-reactive protein (hsCRP) were measured to assess the inflammatory status. The estimation of CAS events was performed by assessing carotid intima-media thickness using Doppler ultrasonography. Univariate analysis was conducted to investigate the variations in biochemical parameters among three groups: normal, carotid atherosclerotic thickening (CAT), and carotid atherosclerotic plaque (CAP) formation. Logistic regression analysis was conducted to identify the risk factors associated with the progression of CAT and CAP. In addition, multivariate linear regression analysis was conducted to identify the independent factors that correlated with hsCRP levels. Results: The study encompassed 3897 participants, with 2992 (76.8%) being males and 905 (23.2%) being females. The incidence of CAT and CAP rose with higher Hcy levels, with an overall odds ratio (OR) of 2.04 [95% confidence intervals (CI) 1.69-2.40] for CAT and 2.68 (95% CI 2.32-3.05) for CAP. After adjusting for gender, age, and blood markers, the OR for CAT and CAP decreased, with an overall OR of 1.05 (95% CI 0.81-1.28) and OR of 1.24 (95% CI 1.02-1.46), respectively. CAP risk independently increased when Hcy level exceeded 19.7 μmol/L (P = 0.030), but not CAT risk (P = 0.299). The impact of hsCRP on CAS events is similar to that of Hcy, and a multiple linear analysis found a significant independent correlation between hsCRP and Hcy (P = 0.001). Conclusions: Elevated Hcy levels can facilitate the formation of CAP through both inflammatory and noninflammatory processes, but it does not independently influence CAT.

Comprehensive analysis identifies crucial genes associated with immune cells mediating progression of carotid atherosclerotic plaque

BACKGROUNDS

Carotid atherosclerosis is prone to rupture and cause ischemic stroke in advanced stages of development. Our research aims to provide markers for the progression of atherosclerosis and potential targets for its treatment.

METHODS

We performed a thorough analysis using various techniques including DEGs, GO/KEGG, xCell, WGCNA, GSEA, and other methods. The gene expression omnibus datasets GSE28829 and GSE43292 were utilized for this comprehensive analysis. The validation datasets employed in this study consisted of GSE41571 and GSE120521 datasets. Finally, we validated PLEK by immunohistochemistry staining in clinical samples.

RESULTS

Using the WGCNA technique, we discovered 636 differentially expressed genes (DEGs) and obtained 12 co-expression modules. Additionally, we discovered two modules that were specifically associated with atherosclerotic plaque. A total of 330 genes that were both present in DEGs and WGCNA results were used to create a protein-protein network in Cytoscape. We used four different algorithms to get the top 10 genes and finally got 6 overlapped genes (TYROBP, ITGB2, ITGAM, PLEK, LCP2, CD86), which are identified by GSE41571 and GSE120521 datasets. Interestingly, the area under curves (AUC) of PLEK is 0.833. Besides, we found PLEK is strongly positively correlated with most lymphocytes and myeloid cells, especially monocytes and macrophages, and negatively correlated with most stromal cells (e.g, neurons, myocytes, and fibroblasts). The expression of PLEK were consistent with the immunohistochemistry results.

CONCLUSIONS

Six genes (TYROBP, ITGB2, ITGAM, PLEK, LCP2, CD86) were found to be connected with carotid atherosclerotic plaques and PLEK may be an important biomarker and a potential therapeutic target.

Computed tomography angiography-based radiomics model for predicting carotid atherosclerotic plaque vulnerability

Vulnerable carotid atherosclerotic plaque (CAP) significantly contributes to ischemic stroke. Neovascularization within plaques is an emerging biomarker linked to plaque vulnerability that can be detected using contrast-enhanced ultrasound (CEUS). Computed tomography angiography (CTA) is a common method used in clinical cerebrovascular assessments that can be employed to evaluate the vulnerability of CAPs. Radiomics is a technique that automatically extracts radiomic features from images. This study aimed to identify radiomic features associated with the neovascularization of CAP and construct a prediction model for CAP vulnerability based on radiomic features. CTA data and clinical data of patients with CAPs who underwent CTA and CEUS between January 2018 and December 2021 in Beijing Hospital were retrospectively collected. The data were divided into a training cohort and a testing cohort using a 7:3 split. According to the examination of CEUS, CAPs were dichotomized into vulnerable and stable groups. 3D Slicer software was used to delineate the region of interest in CTA images, and the Pyradiomics package was used to extract radiomic features in Python. Machine learning algorithms containing logistic regression (LR), support vector machine (SVM), random forest (RF), light gradient boosting machine (LGBM), adaptive boosting (AdaBoost), extreme gradient boosting (XGBoost), and multi-layer perception (MLP) were used to construct the models. The confusion matrix, receiver operating characteristic (ROC) curve, accuracy, precision, recall, and f-1 score were used to evaluate the performance of the models. A total of 74 patients with 110 CAPs were included. In all, 1,316 radiomic features were extracted, and 10 radiomic features were selected for machine-learning model construction. After evaluating several models on the testing cohorts, it was discovered that model_RF outperformed the others, achieving an AUC value of 0.93 (95% CI: 0.88-0.99). The accuracy, precision, recall, and f-1 score of model_RF in the testing cohort were 0.85, 0.87, 0.85, and 0.85, respectively. Radiomic features associated with the neovascularization of CAP were obtained. Our study highlights the potential of radiomics-based models for improving the accuracy and efficiency of diagnosing vulnerable CAP. In particular, the model_RF, utilizing radiomic features extracted from CTA, provides a noninvasive and efficient method for accurately predicting the vulnerability status of CAP. This model shows great potential for offering clinical guidance for early detection and improving patient outcomes.

Serum Uric Acid Levels Are Associated with the Echogenic Features of Carotid Plaque Vulnerability in Elderly Patients with Atherosclerotic Disease

Uric acid is a marker of inflammation and a risk factor for atherosclerosis that has been suggested to play a role in carotid plaque instability. Reduced atherosclerotic plaque echogenicity at ultrasound examination is associated with alarming histopathological features and inflammation. In this study, we investigated the relationship between serum uric acid (SUA) levels and echogenic patterns of plaque instability in elderly subjects with carotid atherosclerosis. Since uric acid metabolism largely depends on renal function, SUA levels were indexed for serum creatinine levels (SUA/SCr). We enrolled 108 patients aged 65 years or more (72.7 ± 5.9 years; 50 females and 58 males) who underwent carotid duplex ultrasound to evaluate plaque echogenicity by greyscale median (GSM). The regression analysis demonstrated a significant inverse association between the GSM and the SUA/SCr ratio (β: -0.567; 95% CI -0.751 to -0.384 and p < 0.0001). Stepwise multivariate regression showed that the SUA/SCr ratio explained 30.3% of GSM variability (β: -0.600; 95% CI -0.777/-0.424, p < 0.0001, and semi-partial correlation 0.303). After a mean period of 3.5 ± 0.5 years, 48 patients were reevaluated according to the same baseline study protocol. The regression analysis demonstrated a still significant inverse association between the GSM and the SUA/SCr ratio (β: -0.462; 95% CI -0.745 to -0.178 and p = 0.002). Stepwise multivariate regression showed that the SUA/SCr ratio explained 28.0% of GSM variability (coefficient -0.584, 95% CI -0.848/-0.319, p < 0.0001, and semi-partial R² 0.280). In conclusion, this study demonstrates that SUA levels indexed for serum creatinine are associated with the echogenic features of carotid plaque vulnerability in elderly patients with atherosclerotic disease. These data could suggest an influential role for uric acid metabolism in carotid plaque biology.

Optimization of the Contrast Agent Injection Protocol for Carotid Artery Dynamic Contrast-Enhanced Magnetic Resonance Imaging

BACKGROUND

The injection protocol used in previous carotid artery dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) studies varied.

PURPOSE

To investigate the effect of contrast injection protocol and optimize this protocol for carotid artery DCE-MRI.

STUDY TYPE

Prospective.

SUBJECTS

Digital phantom and seven patients with carotid atherosclerosis.

FIELD STRENGTH/SEQUENCE

3 T, spoiled gradient recalled echo sequence.

ASSESSMENT

Different injection doses (0.01-0.3 mmol/kg) and effective injection rates (0.01-1 mmol/sec) were tested using a digital carotid plaque phantom considering the contrast pharmacokinetics, DCE-MRI imaging, contrast variation and flow-related imaging artifacts, random time delay between the contrast injection and image acquisition, and pharmacokinetic analysis process. For each injection protocol, combining the root mean square relative error (RMSRE) of the measured K trans and v P maps within the adventitial vasa vasorum from 10 tested time delays by the root mean square produced RMSRE_overall-vv which was used to measure the overall accuracy of the pharmacokinetic parameters. In vivo validation was performed on seven patients with carotid atherosclerosis by imaging them twice using the traditional commonly used protocol and the recommended protocol found by simulation.

STATISTICAL TEST

Student's t-test, chi-square test, and paired t-test, P < 0.05 was considered statistically significant.

RESULTS

A low region of RMSRE_overall-vv with the combination of medium injection dose and low effective injection rate was found. The protocol with injection dose of 0.07 mmol/kg and effective injection rate of 0.06 mmol/sec achieved the minimal RMSRE_overall-vv (4.29%), thus was recommended, which showed more accurate arterial input function. Coinciding with the simulation results, this recommended protocol in in vivo experiments produced significantly fewer image artifacts, lower K trans and v P (P all <0.05) than traditional protocol which overestimated these parameters in simulation.

DATA CONCLUSION

The contrast injection protocol influenced the accuracy of the pharmacokinetics parameter estimation in carotid artery DCE-MRI. The injection protocol with injection dose of 0.07 mmol/kg and effective injection rate of 0.06 mmol/sec was recommended.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 1.

Serum Lipocalin-2 Levels Are Increased and Independently Associated With Early-Stage Renal Damage and Carotid Atherosclerotic Plaque in Patients With T2DM

OBJECTIVES

Diabetic nephropathy (DN), one of the major complications of diabetes mellitus, is the major cause of end-stage renal failure that finally increases the risk of cardiovascular disease and mortality. The aim of this study is to explore the relationship between serum lipocalin-2 (LCN-2) levels and DN and carotid atherosclerotic plaque (CAP) in patients with type 2 diabetes mellitus (T2DM).

METHODS

We have performed a prospective study of 749 T2DM patients with or without DN. Blood samples were collected and used to test serum LCN-2 levels, renal function, as well as biochemical parameters. CAP in these subjects was determined by ultrasonography.

RESULTS

In these 749 subjects with T2DM, an increased morbidity of CAP was observed in T2DM patients with DN as compared with those without this complication (P < 0.05). Interestingly, serum LCN-2 levels were significantly increased in T2DM patients with DN or CAP compared with T2DM alone [97.71 (71.49-130.13) vs. 77.29 (58.83-115.05) ng/ml, P < 0.001]. In addition, serum LCN-2 levels in T2DM patients with DN and CAP were significantly higher than that of T2DM patients with DN or CAP [131.37 (101.43-182.04) vs. 97.71(71.49-130.13) ng/ml, P < 0.001]. Furthermore, serum LCN-2 levels were positively correlated with hemoglobin A1c, systolic blood pressure, hypertension, CAP, and DN, as well as renal function factors including uric acid, creatinine, the estimated glomerular filtration rate, and urinary albumin-to-creatinine ratio, respectively (P < 0.05), but negatively correlated with HDL-c (P < 0.05). The multinomial logistic regression analysis showed that serum LCN-2 was independently associated with DN and CAP in patients with T2DM after the adjustment for risk factors (P < 0.001).

CONCLUSIONS

Early-stage renal damage is a risk factor associated with the incidence of CAP in patients with T2DM. Serum LCN-2 is significantly increased and associated with early-stage renal damage and the incidence of CAP in patients with T2DM.

The Predictive Value of Contrast-Enhanced Ultrasound Combined with Serum miR-124 Level in Acute Cerebral Infarction and Their Correlation with the Contrast Enhancement of Carotid Atherosclerotic Plaque

OBJECTIVE

To investigate the predictive value of contrast-enhanced ultrasound (CEUS) combined with serum miR-124 level in acute cerebral infarction (ACI) and their association with the contrast enhancement of carotid atherosclerotic plaque.

METHODS

Totally 60 patients diagnosed with ACI and 60 controls were included in the study. All the subjects had carotid atherosclerotic plaques, and all of them were examined by CEUS and were tested for serum miR-124 levels.

RESULTS

Time to peak (TTP) and mean transit time (MTT) in the ACI group were significantly shorter than those in the control group (P < 0.05), but the peak intensity ratio (PIR), the area under the curve (AUC), and relative expression levels of serum miR-124 were notably greater in the ACI group (P < 0.05). There were statistically significant differences in TTP, MTT, PIR, AUC, and serum miR-124 expression in patients with different cerebral infarct areas in the ACI group (P < 0.05). Besides, the sensitivity and specificity of serum miR-124 levels for the prediction of ACI were 71.67% and 90.00%, respectively, with a cut-off value of 1.52, and the sensitivity was 86.67% and specificity was 93.33% of CEUS combined with serum miR-124 in the prediction of ACI. The ACI group showed a higher proportion of grades 2 and 3 (P < 0.001). Pearson correlation analysis showed that the intraplaque contrast enhancement was negatively related to TTP and MTT but had a positive correlation with PIR, AUC, and serum miR-124 levels.

CONCLUSION

Grades 2 and 3 intraplaque contrast enhancement and serum miR-124 level of 1.52 had high sensitivity and specificity to predict ACI. Moreover, the CEUS parameters combined with serum miR-124 level could improve the performance in predicting ACI and had auxiliary value in evaluating the stability of carotid atherosclerotic plaques.

Usability of Ultrasonic MicroPure Imaging for Evaluating the Vulnerability of Carotid Atherosclerotic Plaques

OBJECTIVE

MicroPure is an ultrasound imaging technology used for detecting microcalcifications. This study aimed to evaluate the usefulness of the Firefly sign in ultrasonic MicroPure imaging for detecting the vulnerability of carotid plaques.

METHODS

Ultrasonic grey-scale imaging was used to detect carotid plaques. Ultrasonic MicroPure imaging was used to detect the Firefly sign and to determine the location and number of Firefly signs.

RESULTS

A total of 142 plaques were detected in 72 patients, and 62.0% were Firefly-positive plaques. The length or thickness, the risk of rupture and the percentage of vulnerable plaques were greater in the Firefly-positive plaques than in Firefly-negative plaques. The assessment of plaque vulnerability built on the 4-point Firefly scoring system showed that the area under the ROC curve was 0.750 (P < .001). The sensitivity and specificity of vulnerable plaques with a score of 2 points were 71.9 and 73.6%, respectively.

CONCLUSION

The Firefly signs are widely present in carotid atherosclerotic plaques and can be detected with ultrasonic MicroPure imaging. Firefly signs located in fibrous caps may be associated with plaque vulnerability.

Endovascular Debulking of Human Carotid Plaques by Using an Excimer Laser Combined With Balloon Angioplasty: An ex vivo Study

Purpose: We aimed to evaluate the safety and effectiveness of applying an excimer laser in debulking human carotid atherosclerotic plaques by investigating the distal debris, plaque luminal gain, and micromorphology of the plaque surface.

Methods: Eighteen plaque samples obtained from carotid endarterectomy (CEA) were randomly allocated to the excimer laser ablation (45 mJ/mm², 25 Hz) alone group (group 1), balloon angioplasty (8 atm) alone group (group 2), and excimer laser ablation combined with balloon angioplasty group (group 3). Hematoxylin–eosin staining and Movat's pentachrome staining were performed on the collected particles to quantify the size and composition of the debris. The superficial micromorphological structure of the plaque lumen surface after device treatments was observed using a scanning electron microscope. Micro-CT, tissue sections, and pathological stainings were applied to the treated plaques. The plaque lumen and artery lumen were three-dimensionally reconstructed using clinical computed tomography angiography and the micro-CT images. Lumen enlargement was set as the main measurement of effectiveness.

Results: Group 3 produced the highest luminal gain (5.40 ± 4.51 mm²), while the other two groups had gains of 4.05 ± 3.20 and 3.77 ± 2.55 mm². Both devices caused disruptions to the plaque lumen surface. Laser ablation exposed the fibers under the endothelium and balloon angioplasty cracked the surface. The mean amounts were 3,611 ± 1,475.4 for group 1, 2,828 ± 1,266.7 for group 2, and 4,400 ± 2,567.9 for group 3. More than 90% of the distal debris was smaller than 10 μm. Group 2 produced the most debris with Feret (maximum caliper diameter) ≥ 40 μm; group 1 had the least. There was little difference in the contents of collagen and reticular fiber in the debris in each group, but a big difference was observed in the contents of fibrin and mucin.

Conclusion: Excimer laser ablation could significantly increase the luminal gain of carotid plaque with high stenosis. Excimer laser combined with balloon angioplasty achieved the highest lumen enlargement. Our result also suggests that the embolic protection strategy needs to be renewed for the application of a plaque debulking device in the future.

Efficacy of simvastatin on carotid atherosclerotic plaque and its effects on serum inflammatory factors and cardiocerebrovascular events in elderly patients

To investigate the efficacy of simvastatin on carotid atherosclerotic plaque (CAP) and its effects on serum inflammatory factors and cardiocerebrovascular events in elderly patients, 130 elderly patients with CAP were randomly divided into observation (n=65) and control groups (n=65). The control group was treated with 75 mg/day aspirin enteric-coated tablets, and the observation group was administered additional 20 mg/day simvastatin. Serum total cholesterol, triglyceride, and high- and low-density lipoprotein cholesterol levels (evaluated via the endpoint method) were determined in both groups. Furthermore, the length, thickness and number of CAPs was measured using color Doppler ultrasonography. In addition, levels of inflammatory biomarkers including high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nitric oxide, D-dimer and fibrinogen, as well as change in microemboli count, were also compared After treatment, the observation group exhibited a significant reduction in size, thickness, and number of CAP and intima-media thickness compared with before treatment. However, no significant difference was found in the indicators of CAPs in the control group before and after treatment. The levels of total cholesterol, triglyceride, and low-density lipid cholesterol decreased, while high-density lipid cholesterol increased in the observation group after treatment, with notable changes in the observation group compared with in the control group. Overall response rate was higher in the observation group compared with the control group. TNF-α, IL-6, and hs-CRP levels in the observation group decreased after treatment compared with those before treatment and those in the control group. Furthermore, the rate of microemboli positivity was lower in the observation group than in the control group. Moreover, the overall incidence of acute cardiocerebrovascular events was lower in the observation group than in the control group. Therefore, it was demonstrated that simvastatin can reduce blood lipid levels, decrease the quantity and size of plaques, alleviate inflammatory response, reduce microemboli formation and reduce the risk of cardiocerebrovascular events in elderly patients with CAP.

Clinical study of atherosclerotic plaque in the carotid artery and lower extremities in patients with obstructive sleep apnea-hypopnea syndrome

OBJECTIVE

The present study aimed to explore the relationship between young and middle-aged patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) and atherosclerotic plaque of the carotid artery and lower extremities.

METHODS

A total of 110 patients diagnosed with OSAHS by polysomnography in the researchers' hospital from September 2018 to September 2019 were selected as the research objects. The enrolled patients were divided into a mild group (36 cases), a moderate group (38 cases), and a severe group (36 cases). Another 36 healthy subjects were set up as the non-OSAHS group. All the selected subjects were examined by color Doppler ultrasound of the carotid artery and lower extremity arteries.

RESULTS

The detection rate of atherosclerotic plaque of the carotid artery and/or lower extremities in patients with OSAHS was significantly higher than that in the non-OSAHS group (P < 0.05), and the incidence of plaque tended to increase along with an increase in the degree of OSAHS.

CONCLUSION

The findings indicate that OSAHS might be an independent influencing factor for atherosclerosis.

MicroRNA-564 inhibits the progression of non-small cell lung cancer via targeting plexin A4

Νon-small cell lung cancer (NSCLC) is the most frequently diagnosed type of cancer, and the most prevalent cause of cancer-associated mortality. The present study aimed to investigate whether microRNA (miR)-564 influences NSCLC progression by regulating NSCLC cell growth and migration, via targeting plexin A4. Therefore, the expression levels of miR-564 and plexin A4 were evaluated in NSCLC specimens or cells using reverse transcription-quantitative PCR. Furthermore, colony formation and Cell Counting Kit-8 assays were performed to determine the proliferative ability of NSCLC cells. The cell migration capacity was assessed using a Transwell assay. In addition, to examine the binding ability of miR-564 on the plexin A4 3'-untranslated region (3'UTR), a dual-luciferase reporter assay was performed. A mouse xenograft model was established to evaluate the effect of miR-564 knockdown on tumor growth in vivo, whereas the expression of plexin A4 and Ki67 in NSCLC tissues was detected using immunohistochemistry. Notably, miR-564 was downregulated in both NSCLC cell lines and tissues, while its overexpression, following transfection with miR-564 mimics, attenuated the proliferation and proliferation, migration and invasion of NSCLC cells. By contrast, silencing of miR-564 using a miR-564 inhibitor promoted NSCLC cell proliferation, migration and invasion. The luciferase assay revealed that miR-564 directly targeted the plexin A4 3'UTR in A549 and H460 cells. Additionally, the overexpression of plexin A4 rescued the effect of miR-564 on NSCLC cell proliferation, migration and invasion abilities. Further in vivo studies demonstrated that miR-564 knockdown promoted NSCLC growth, while miR-564 overexpression resulted in the opposite effect in nude mice. Overall, the results of the present study revealed that miR-564 promotes the proliferation and migration of NSCLC cells, both in vitro and in vivo, via targeting plexin A4. Therefore, miR-564 may be considered as a possible therapeutic target for NSCLC.

Studying the Factors of Human Carotid Atherosclerotic Plaque Rupture, by Calculating Stress/Strain in the Plaque, Based on CEUS Images: A Numerical Study

Carotid plaque neovascularization is one of the major factors for the classification of vulnerable plaque, but the axial force effects of the pulsatile blood flow on the plaque with neovessel and intraplaque hemorrhage was unclear. Together with the severity of stenosis, the fibrous cap thickness, large lipid core, and the neovascularization followed by intraplaque hemorrhage (IPH) have been regarded as high-risk features of plaque rupture. In this work, the effects of these factors were evaluated on the progression and rupture of the carotid atherosclerotic plaques. Five geometries of carotid artery plaque were developed based on contrast-enhanced ultrasound (CEUS) images, which contain two types of neovessel and IPH, and geometry without neovessel and IPH. A one-way fluid-structure interaction model was applied to compute the maximum principal stress and strain in the plaque. For that hyper-elastic and non-linear material, Yeoh 3rd Order strain energy density function was used for components of the plaque. The simulation results indicated that the maximum principal stress of plaque in the carotid artery was higher when the degree of the luminal stenosis increased and the thickness of the fibrous cap decreased. The neovessels within the plaque could introduce a 2.5% increments of deformation in the plaque under the pulsatile blood flow pressure. The IPH also contributed to the increased risk of plaque rupture that a gain of stress was 8.983, 14.526, and 34.47 kPa for the plaque with 50, 65, and 75%, respectively, when comparing stress in the plaque with IPH distributed at the middle to the shoulder of the plaque. In conclusion, neovascularization in the plaque could reduce the stability of the plaque by increasing the stress within the plaque. Also, the risk of plaque rupture increased when large luminal stenosis, thin fibrous cap, and IPH were observed.

Association of the Total White Blood Cell, Neutrophils, and Monocytes Count With the Presence, Severity, and Types of Carotid Atherosclerotic Plaque

Background: Previous studies have indicated that white blood cells (WBCs) might contribute to the development of atherosclerosis. However, the associations of WBCs and WBC subgroups with carotid atherosclerotic plaque (CAP) have not been compared. Methods: A cross-sectional study including 3,569 healthy Chinese adults was conducted between January 2016 and December 2018 in Zhengzhou, China, to explore the associations of WBC and WBC subtypes with the presence, severity, and types of CAPs. Fasting peripheral venous blood was collected for measurement of the total WBC and WBC subtype counts. The size, composition, and types of CAPs in the common carotid artery, the internal carotid artery, and the external carotid artery were measured bilaterally using B-mode ultrasound. Results: The total WBC, neutrophil, and monocyte counts showed significant associations with the presence of CAPs in men, but not in women, with the adjusted odds ratios (95% CI) in the highest (compared to the lowest) quartile 1.99 (1.33-2.97), 1.65 (1.10-2.47), and 2.17 (1.41-3.18) (P _trend = 0.004, P _trend = 0.004, and P _trend < 0.001), respectively. The three leukocyte counts were also significantly associated with the severity of CAPs, as judged by the count of CAPs, maximal internal carotid plaque thickness, and the plaque score (all P < 0.01, P _trend < 0.05). Compared with individuals without CAPs, those with echolucent plaques had significantly increased total WBC and neutrophil counts, whereas those with polytype plaques had a significantly increased monocyte count. Conclusion: WBC, neutrophil, and monocyte counts were significantly associated with the presence, severity, and types of CAPs in a healthy Chinese population.

Four Different Carotid Atherosclerotic Behaviors Based on Luminal Stenosis and Plaque Characteristics in Symptomatic Patients: An in Vivo Study

Correct stratification of ischemic stroke risk allows for the proper treatment of carotid atherosclerotic disease. We seek to differentiate plaque types based on stenosis level and plaque morphology. The Chinese Atherosclerosis Risk Evaluation (CARE-II) study is a cross-sectional, observational, multicenter study to assess carotid atherosclerotic plaques in symptomatic subjects using vessel wall magnetic resonance imaging. Plaque morphology and presence of plaque components were reviewed using multi-contrast magnetic resonance imaging. The carotid arteries were divided into four groups based on stenosis level and plaque components. Out of 1072 ischemic stroke subjects, 452 ipsilateral side carotid arteries were included. Significant stenosis (SS) (≥50% stenosis) with high-risk plaque (HRP) features was present in 37 arteries (8.2%), SS(+)/HRP(-) in 29 arteries (6.4%), SS(-)/HRP(+) in 57 arteries (12.6%), and SS(-)/HRP(-) in 329 arteries (72.8%). The prevalence of SS(-)/HRP(+) arteries in this cohort was substantial and had greater wall thickness than the SS(+)/HRP(-) group. These arteries may be misclassified for carotid revascularization by current guidelines based on the degree of luminal stenosis only. These findings have implications for further studies to assess stroke risk using vessel wall imaging.

Association between non-HDL-C/HDL-C ratio and carotid atherosclerosis in postmenopausal middle-aged women

Background: A novel lipid relation, the non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol (non-HDL-C/HDL-C) ratio gathers information on all atherogenic and antiatherogenic particles on a single date. The relationship between this lipid marker and the presence of carotid atherosclerotic plaque (CAP) in postmenopausal women is unknown. Methods: Postmenopausal women in primary prevention up to 70 years of age were recruited. Association between the non-HDL-C/HDL-C ratio and presence of CAP, assessed by ultrasonography, was analyzed. Receiver operating characteristic (ROC) curve analysis was performed. Results: A total of 440 females with a mean age of 58.1 ± 5.3 years were recruited. The mean non-HDL-C/HDL ratio was 3.1 ± 1.2 and 28.2% of woman had CAP. A positive relationship was seen between quintiles of the non-HDL-C/HDL-C ratio and prevalence of CAP (p < 0.001). Regardless of other risk factors, women with higher non-HDL-C/HDL-C ratios had a greater chance of having CAP (odds ratio 1.30, 95% confidence interval: 1.07-1.58, p = 0.009). In the ROC curve analysis, the area under the curve of the non-HDL-C/HDL ratio for detecting CAP was 0.703 (95% confidence interval: 0.640-0.765) and the optimal cut-off point was 3.0 (Youden index 0.395). Conclusion: The present study suggests that the non-HDL-C/HDL-C ratio might be a strong marker for predicting the risk of CAP in postmenopausal women.

A Preliminary Study of the Association between Apolipoprotein E Promoter Methylation and Atherosclerotic Cerebral Infarction

AIM

To investigate association of Apolipoprotein E (ApoE) gene promoter methylation with atherosclerotic cerebral infarction (ACI) in the Han Chinese population.

METHODS

Twenty-six ACI patients (the case group) and 26 healthy (the control group) were recruited randomly from Henan Han nationality population, from April 2016 to August 2016. Bisulfite pyrosequencing technology was used to examine the role of the aberrant gene promoter methylation in ACI in Han Chinese population. Especially, we used the odds ratio and 95% confidence interval (95% CI) method to elevate the correlation between ApoE Promoter Methylation and ACI.

RESULTS

The case group was significantly more likely to have hypertension and carotid atherosclerotic plaques (Table 1). The case group had significantly lower levels of high-density lipoprotein cholesterol (HDL-C), folate, and higher levels of homocysteine (Table 2). We observed that ACI patients (n = 26) had significantly higher methylation levels at cytosine-phosphate-guanine (CpG) 14 and CpG16 compared with controls (n = 26) (Table 3). Importantly, our results indicated a significant association between ApoE promoter methylation and ACI (OR = 16.146; 95% CI, 1.154-225.832; P* < .05; P*: adjusted for age, gender, carotid atherosclerotic plaque, hypertension, HDL-C, homocysteine, and folate) (Table 4).

CONCLUSIONS

Our study indicates that ApoE promoter methylation may be associated with ACI in Han Chinese people.

LDL-C:HDL-C ratio and common carotid plaque in Xinjiang Uygur obese adults: a cross-sectional study

OBJECTIVE

The aim of this study was to explore the relationship between low-density lipoprotein cholesterol:high-density lipoprotein cholesterol (LDL-C:HDL-C) ratio and common carotid atherosclerotic plaque (CCAP) among obese adults of Uygur community in Xinjiang, China.

DESIGN

A hospital-based cross-sectional study.

SETTING

First Affiliated Hospital of Xinjiang Medical University.

PARTICIPANTS

A total of 1449 obese adults of Uygur population who were free of coronary artery disease were included in our study from 1 January 2014 to 31 December 2016.

METHODOLOGY

Lipid profiles, other routine laboratory parameters and intima-media thickness of the common carotid artery were measured in all participants. Multivariate logistic regression analysis was used to examine the association between LDL-C:HDL-C ratio and CCAP.

RESULTS

Four hundred and fifteen (28.64%) participants had CCAP. Participants with CCAP had significantly higher LDL-C:HDL-C ratio compared with those without CCAP (3.21 [2.50, 3.88] vs 2.33 [1.95, 2.97], p<0.001). Multivariate logistic regression analysis showed high LDL-C:HDL-C ratio as independent predictor of CCAP after adjusting for conventional cardiovascular risk factors. The top LDL-C:HDL-C ratio quartile (≥3.25) had an OR of 9.355 (95% CI 6.181 to 14.157) compared with the bottom quartile (<2.07) of LDL-C:HDL-C ratio (p<0.001) after adjustment for age, body mass index, smoking, diabetes mellitus and serum level of total cholesterol.

CONCLUSION

CCAP is highly prevalent in Uygur obese adults. A high LDL-C:HDL-C ratio is an independent predictor of CCAP. It may help identify obese individuals who are at high risk of CCAP and who may benefit from intensive LDL-lowering therapy.

Prognostic value of high-resolution magnetic resonance imaging in evaluating carotid atherosclerotic plaque in patients with ischemic stroke

BACKGROUND

Ischemic stroke (IS) is a devastating occurrence affecting millions worldwide. This study aimed to evaluate the prognostic value of high-resolution magnetic resonance imaging (HRMRI) in assessing carotid atherosclerotic plaque in IS patients.

METHODS

Between January 2013 and March 2015, 338 IS patients were recruited for the investigative purposes of the study. All participants of the study underwent an HRMRI inspection procedure after being admitted into the hospital. During this study, we systematically analyzed and measured various types of fibrous caps, lipid compositions, and plaque lipid ratios. Univariate and multivariate logistic regression analyses were performed for predicting prognosis of IS patients. A receiver-operating characteristic (ROC) curve was employed to determine the accuracy of the IS prognosis.

RESULTS

The percentage of type I fibrous caps exhibited significant decrease, while the percentage of type III fibrous caps, lipid compositions, and lipid ratios all displayed increase. The results of the univariate analysis indicated that age, hypertension, hyperlipidemia, treatment regimens, fibrous cap type, plaque type, lipid composition, and lipid ratio shared a correlation in regards to the poor prognosis of IS patients. Multivariate logistic regression analysis demonstrated that the prognosis of IS patients was not necessarily dependent on fibrous cap type, plaque type, or age. ROC curves revealed that the HRMRI possessed a strong predicative ability in relation to the identification of the prognosis of IS patients through factors such as type of plaque and fibrous caps determination.

CONCLUSION

Our study conclusively intimated the promise of HRMRI as an evaluative tool for the determination of carotid atherosclerotic plaques in patients with IS.

Comparison of diagnostic values of ultrasound micro-flow imaging and contrast-enhanced ultrasound for neovascularization in carotid plaques

The aim of the present study was to compare the diagnostic values of ultrasound micro-flow imaging (SMI) and contrast-enhanced ultrasound (CEUS) for neovascularization in carotid plaques, and to investigate their capacities for predicting the risks of cerebral stroke. A total of 39 patients (64 carotid plaques) with severe carotid artery stenosis undergoing carotid endarterectomy were selected between February 2015 and February 2016, and SMI and CEUS were used to detect neovascularization in plaques. According to the CEUS dynamic graph of plaques, the enhanced intensity visual scales and contrast parameters were obtained. Carotid atherosclerotic plaques were divided into 4 groups. The differences in the enhanced intensity visual scales, contrast parameters, and gray-scale median (GSM) values among the 4 groups were analyzed. Carotid plaque tissue samples from patients were stained for CD34, and the consistency of the methods for the diagnosis of neovascularization in plaques was analyzed. The differences in GSM values, enhanced intensities, and enhanced densities among the 4 groups of plaques were statistically significant (F=29.365, χ²=29.025, χ²=30.871, P<0.001); the differences in enhanced intensities of carotid atherosclerotic plaques with different echo types were statistically significant (χ²=17.951, P<0.001). The enhanced intensity of plaques was negatively correlated with the GSM value (r=−0.376, P<0.01), and the enhanced density of plaques was negatively correlated with the GSM value (r=−0.252, P<0.01). SMI and CEUS grading had good consistency (κ=0.860>0), there were statistically significant differences in new vessel densities with different SMI gradings (P<0.001), and the clinical symptoms and severity were positively correlated with SMI grading (rs=0.592>0). In conclusion, SMI and CEUS have good consistency for evaluating neovascularization in carotid plaques, and have good clinical value for evaluating neovascularization in carotid plaques.

High-resolution magnetic resonance imaging of carotid atherosclerotic plaques - a correlation study with histopathology

BACKGROUND

This study aimed to utilize high-resolution magnetic resonance imaging (MRI) to investigate the characteristics of stable and vulnerable carotid arteriosclerotic plaques, with correlations to histopathological findings.

PATIENTS AND METHODS

High-resolution MRI was performed in 817 patients, using three-dimensional magnetic resonance angiography. Plaque composition was evaluated by measuring the areas occupied by calcification, a lipid-rich necrotic core, intra-plaque haemorrhage, and fibrous cap rupture. Plaque morphology was analysed by measuring vessel wall area, thickness, and luminal area at the bifurcation of the common carotid artery. Plaque tissues were sampled during carotid endarterectomy and examined using haematoxylin-eosin, Oil Red O, Masson trichrome staining, and immunohistochemical staining for CD68.

RESULTS

Patients were divided into stable plaque group (n = 462) and vulnerable plaque group (n = 355), based on intraoperative observations and postoperative histopathological findings. Compared to the stable plaque group, the vulnerable plaque group exhibited increased vessel wall areas and thickness, and decreased mean luminal areas (P < 0.001). The vulnerable plaque group also had a lower collagen content, a higher lipid content, and higher CD68 expression in plaque tissues on histological examinations (P < 0.01). Incidences of lipid-rich necrotic core (38.1 % vs. 34.3 %), intra-plaque haemorrhage (26.9 % vs. 22.8 %), plaque calcification (45.2 % vs. 40.9 %), and fibrous cap rupture (36.0 % vs 39.8 %) in the plaques were concordant with MRI observations and histopathological findings (p > 0.05).

CONCLUSIONS

Stable and vulnerable carotid plaques had different morphologies and compositions. High-resolution MRI can assess such differences qualitatively and quantitatively in vivo and provide guidance for risk stratification and management.

Association between serum 25-hydroxyvitamin D and carotid atherosclerotic plaque in Chinese type 2 diabetic patients

In this study, we investigated the distribution of vitamin D and its association with carotid atherosclerotic plaque (CP) in Chinese type 2 diabetic (T2D) patients. We performed a cross-sectional study in 210 T2D and 94 age- and gender-matched nondiabetic patients during winter months, by determining serum 25-hydroxyvitamin D (25(OH)D) levels in both diabetic and nondiabetic controls. We carried out measurements of B-mode ultrasonography of carotid arteries in each T2D patient. The 25(OH)D concentration was 26.25 nmol/L among the T2D patients. About 93.3% T2D patients suffered from hypovitaminosis D. First, we found a clear inverse correlation between the 25(OH)D concentration and CP (P <0.001). Second, an association between 25(OH)D and macrovascular disease was significant (P = 0.005). In multivariate logistic regression analysis, decreasing 25(OH)D concentration was markedly associated with CP in T2D patients. Third, after adjusting for the confounding factors, we also observed a positive correlation between low levels of 25(OH)D in T2D patients with CP, when the following parameters were measured: old age (odds ratio [OR] = 2.533, P = 0.013); smoking (OR = 3.872, P = 0.001); and high level of low-density lipoprotein (LDL) cholesterol (OR = 2.776, P = 0.009). Thus, we concluded that high prevalence of hypovitaminosis D exists in Chinese T2D patients. Further, we found a significant association between low concentration of serum 25(OH)D and the existence of high body mass index, and high circulating LDL to be substantially positive predictors of patients with CP in T2D.

Correlation between aortic/carotid atherosclerotic plaques and cerebral infarction

The aim of this study was to investigate the correlation between aortic/carotid atherosclerotic plaques and cerebral infarction. We examined 116 cases of cerebral infarction using transcranial Doppler ultrasound in order to exclude cerebrovascular stenosis. Transesophageal echocardiography and color Doppler ultrasound were used to detect aortic atherosclerotic plaques (AAPs) and carotid atherosclerotic plaques (CAPs). AAPs were detected in a total of 70 of the 116 cases (60.3%), including 56 with moderate/severe atherosclerotic changes (48.3%). The difference in the incidence of various types of infarction between APP severity levels was significant (P<0.01). Of the 116 cases, 64 had CAPs (55.2%), including 46 with unstable plaque (39.7%). The difference in the incidence of various types of infarction between CAP stability levels was significant (P<0.01). The results indicate that moderate/severe AAP and unstable CAP are significant causes of embolic infarction without stenosis in the internal carotid arteries.

Vascular endothelial growth factor and monocyte chemoattractant protein-1 levels unaltered in symptomatic atherosclerotic carotid plaque patients from north India

We aimed to identify the role of vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein (MCP-1) as a serum biomarker of symptomatic carotid atherosclerotic plaque in North Indian population. Individuals with symptomatic carotid atherosclerotic plaque have high risk of ischemic stroke. Previous studies from western countries have shown an association between VEGF and MCP-1 levels and the incidence of ischemic stroke. In this study, venous blood from 110 human subjects was collected, 57 blood samples of which were obtained from patients with carotid plaques, 38 neurological controls without carotid plaques, and another 15 healthy controls who had no history of serious illness. Serum VEGF and MCP-1 levels were measured using commercially available enzyme-linked immunosorbent assay. We also correlated the data clinically and carried out risk factor analysis based on the detailed questionnaire obtained from each patient. For risk factor analysis, a total of 70 symptomatic carotid plaque cases and equal number of age and sex matched healthy controls were analyzed. We found that serum VEGF levels in carotid plaque patients did not show any significant change when compared to either of the controls. Similarly, there was no significant upregulation of MCP-1 in the serum of these patients. The risk factor analysis revealed that hypertension, diabetes, and physical inactivity were the main correlates of carotid atherosclerosis (p < 0.05). Prevalence of patients was higher residing in urban areas as compared to rural region. We also found that patients coming from mountain region were relatively less vulnerable to cerebral atherosclerosis as compared to the ones residing at non mountain region. On the contrary, smoking, obesity, dyslipidemia, alcohol consumption, and tobacco chewing were not observed as the determinants of carotid atherosclerosis risk in North India (p > 0.05). We conclude that the pathogenesis of carotid plaques may progress independent of these inflammatory molecules. In parallel, risk factor analysis indicates hypertension, diabetes, and sedentary lifestyle as the most significant risk factors of ischemic stroke identified in North India. This could be helpful in early identification of subjects at risk for stroke and devising health care strategies.