Using arterial blood as a substitute for venous blood in routine biochemistry parameter examinations in rabbits.

BACKGROUND: It has been widely accepted that there is a significant difference in peripheral blood oxygen between arteries and veins. Therefore, arterial blood has been collected for blood gas analysis, and venous blood, because it is convenient to collect, has been used for most laboratory examinations. However, venous blood is always difficult to collect in rabbits; in contrast, arterial blood is easier to obtain, and research on whether arterial blood can be used instead of venous blood for routine biochemical parameter examination is rare. Therefore, the present study was designed to explore whether arterial blood can be used as a substitute for venous blood for routine biochemistry parameter examination in rabbits. RESULTS: Three venous blood samples with gross hemolysis were excluded. Venous and arterial blood samples were obtained from forty-two rabbits. Arterial blood samples correlate well with venous blood in alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine transaminase (ALT), gamma-glutamyl transpeptidase (GGT), total protein (TP), globulin (GLB), serum total cholesterol (TC), serum triglyceride (TG), high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), urea (Ur) and creatinine (Cr) levels by Deming regression analysis with slopes ranging from 0.893 to 1.176 and intercepts ranging from - 4.886 to 5.835. Bland-Altman analysis showed that the two sample parameters had 93%-98% of the points within the 95% consistency limits. There were significant differences between venous blood and arterial blood in ALP, TP, TC, TG, HDL, LDL and Cr, while AST, ALT, GGT, GLB and Ur showed no significant differences. CONCLUSIONS: Arterial blood can be a substitute for venous blood in routine biochemistry parameter examinations in rabbits, especially in situations where venous blood is difficult to collect.

Validation of PDE9A Gene Identified in GWAS Showing Strong Association with Milk Production Traits in Chinese Holstein.

Phosphodiesterase9A (PDE9A) is a cyclic guanosine monophosphate (cGMP)-specific enzyme widely expressed among the tissues, which is important in activating cGMP-dependent signaling pathways. In our previous genome-wide association study, a single nucleotide polymorphism (SNP) (BTA-55340-no-rs(b)) located in the intron 14 of PDE9A, was found to be significantly associated with protein yield. In addition, we found that PDE9A was highly expressed in mammary gland by analyzing its mRNA expression in different tissues. The objectives of this study were to identify genetic polymorphisms of PDE9A and to determine the effects of these variants on milk production traits in dairy cattle. DNA sequencing identified 11 single nucleotide polymorphisms (SNPs) and six SNPs in 5' regulatory region were genotyped to test for the subsequent association analyses. After Bonferroni correction for multiple testing, all these identified SNPs were statistically significant for one or more milk production traits (p < 0.0001~0.0077). Interestingly, haplotype-based association analysis revealed similar effects on milk production traits (p < 0.01). In follow-up RNA expression analyses, two SNPs (c.-1376 G>A, c.-724 A>G) were involved in the regulation of gene expression. Consequently, our findings provide confirmatory evidences for associations of PDE9A variants with milk production traits and these identified SNPs may serve as genetic markers to accelerate Chinese Holstein breeding program.

Incremental Prognostic Value of Carotid Plaque-RADS Over Stenosis Degree in Relation to Stroke Risk.

BACKGROUND: Recently, a standardized classification system for carotid atherosclerotic plaques, known as Carotid Plaque-RADS (Reporting and Data System), has been introduced. However, its capacity to improve stroke risk stratification beyond traditional stenosis degree assessment has not been extensively explored. OBJECTIVES: This study aimed to determine the incremental prognostic value of Carotid Plaque-RADS over stenosis degree for stroke risk. METHODS: A retrospective analysis was performed on data from January 2010 to December 2021, involving subjects who underwent magnetic resonance imaging, computed tomography angiography, and ultrasound evaluations of the carotid artery. Disease-free survival (DFS) and recurrence-free survival (RFS) rates were compared across different stenosis degrees, Carotid Plaque-RADS categories, and their combination, using the Kaplan-Meier and net reclassification improvement formula. RESULTS: The study enrolled 1,378 subjects. During a follow-up period of 57 ± 25 months, 4.6% of 987 asymptomatic individuals and 16.9% of 391 subjects with stroke history experienced initial and recurrent strokes, respectively. Significant differences in DFS and RFS rates were found between subjects with mild/moderate and severe stenosis (P < 0.001). Significant differences in DFS rates were observed across Carotid Plaque-RADS categories (P < 0.001), with a notable decrease in DFS rates as Carotid Plaque-RADS categories increased from 1 to 4. This trend was similar in subjects with a history of stroke (P < 0.001). For patients with mild/moderate stenosis, significant differences in DFS and RFS rates were found between those with Carotid Plaque-RADS of ≥3 vs <3 (P < 0.001). Correct reclassification was achieved for 3.3% (32 of 979) of asymptomatic individuals and 9.7% (37 of 381) of subjects with a stroke history initially identified with mild/moderate stenosis. Incorporating Carotid Plaque-RADS with stenosis grading markedly improved risk assessment, resulting in net reclassification improvement of 63.8% for initial stroke and 47.8% for recurrent stroke prediction. The likelihood ratio test demonstrated that Carotid Plaque-RADS scores significantly enhanced the prognostic accuracy of stenosis degrees for both asymptomatic individuals and patients with a history of stroke (both P < 0.001). CONCLUSIONS: Carotid Plaque-RADS significantly improves stroke risk stratification over traditional stenosis grading, especially in mild/moderate stenosis cases.

A Radiomics-Based Nomogram Using Ultrasound Carotid Plaque Evaluation For Predicting Cerebro-Cardiovascular Events In Asymptomatic Patients.

RATIONALE AND OBJECTIVES: This study aims to assess whether a radiomics-based nomogram correlates with a higher risk of future cerebro-cardiovascular events in patients with asymptomatic carotid plaques. Additionally, it investigates the nomogram's contribution to the revised Framingham Stroke Risk Profile (rFSRP) for predicting cerebro-cardiovascular risk. MATERIALS AND METHODS: Predictive models aimed at identifying an increased risk of future cerebro-cardiovascular events were developed and internally validated at one center, then externally validated at two other centers. Survival curves, constructed using the Kaplan-Meier method, were compared through the log-rank test. RESULTS: This study included a total of 2009 patients (3946 images). The final nomogram was generated using multivariate Cox regression variables, including dyslipidemia, lumen diameter, plaque echogenicity, and ultrasonography (US)-based radiomics risk. The Harrell's concordance index (C-index) for predicting events-free survival (EFS) was 0.708 in the training cohort, 0.574 in the external validation cohort 1, 0.632 in the internal validation cohort, and 0.639 in the external validation cohort 2. The final nomogram showed a significant increase in C-index compared to the clinical, conventional US, and US-based radiomics models (all P < 0.05). Furthermore, the final nomogram-assisted method significantly improved the sensitivity and accuracy of radiologists' visual qualitative score of plaque (both P < 0.001). Among 1058 patients with corresponding 1588 plaque US images classified as low-risk by the rFSRP, 75 (7.1%) patients with corresponding 93 (5.9%) carotid plaque images were appropriately reclassified to the high-risk category by the final nomogram. CONCLUSION: The radiomics-based nomogram demonstrated accurate prediction of cerebro-cardiovascular events in patients with asymptomatic carotid plaques. It also improved the sensitivity and accuracy of radiologists' visual qualitative score of carotid plaque and enhanced the risk stratification ability of rFSRP. SUMMARY: The radiomics-based nomogram allowed accurate prediction of cerebro-cardiovascular events, especially ipsilateral ischemic stroke in patients with asymptomatic carotid atherosclerotic plaques. KEY RESULTS: The radiomics-based nomogram allowed accurate prediction of cerebro-cardiovascular events, especially ipsilateral ischemic stroke in patients with asymptomatic carotid atherosclerotic plaques. The radiomics-based nomogram improved the sensitivity and accuracy of radiologists' visual qualitative score of carotid plaque. The radiomics-based nomogram improved the discrimination of high-risk populations from low-risk populations in asymptomatic patients with carotid atherosclerotic plaques and the risk stratification capability of the rFSRP.

Use of carotid plaque neovascularization at contrast-enhanced US to predict coronary events in patients with coronary artery disease.

PURPOSE: To determine whether carotid plaque neovascularization as assessed with contrast-enhanced ultrasonography (US) can help predict future coronary events in patients with stable coronary artery disease (CAD). MATERIALS AND METHODS: The study was approved by the hospital ethics committee, and informed consent was obtained from all patients. Three hundred twelve consecutive patients (228 men; mean age, 63 years ± 9; age range, 42-88 years) with both CAD and at least one carotid plaque thicker than 2.0 mm underwent both standard and contrast-enhanced carotid US. Patients with stable CAD were followed up for 8-47 months (mean, 33 months ± 9) or until a coronary event occurred. Statistical analysis was performed with the Student t test, χ(2) analysis, Kaplan-Meier method, and Cox proportional hazards regression models. RESULTS: Contrast material enhancement of plaque was seen in 42 of 51 patients (82%) with acute coronary syndrome (ACS) and 114 of 261 patients (43.7%) with stable CAD (P < .001). Coronary events occurred during the follow-up period in 24 of 111 patients (21.6%) with contrast material enhancement of plaque and only seven of 137 patients (5.1%) without enhancement (P< .001). In 248 patients with stable CAD and follow-up, Kaplan-Meier analysis demonstrated a significantly higher probability of developing coronary events in patients with contrast material enhancement of plaque than in those without contrast material enhancement (P < .001). The presence of contrast material enhancement of plaque was a significant and independent predictor of future coronary events in patients with stable CAD (odds ratio: 3.90; 95% confidence interval: 1.60, 9.46; P = .003). CONCLUSION: Contrast material enhancement of plaque is more common in patients with ACS than in those with stable CAD and is a significant and independent predictor of future coronary events in patients with stable CAD, suggesting that noninvasive contrast-enhanced carotid US may be used as a method for risk stratification of patients with stable CAD.

Value of Intraplaque Neovascularization on Contrast-Enhanced Ultrasonography in Predicting Ischemic Stroke Recurrence in Patients With Carotid Atherosclerotic Plaque.

OBJECTIVE: Patients with a history of ischemic stroke are at risk for a second ischemic stroke. This study aimed to investigate the relationship between carotid plaque enhancement on perfluorobutane microbubble contrast-enhanced ultrasonography (CEUS) and future recurrent stroke, and to determine whether plaque enhancement can contribute to risk assessment for recurrent stroke compared with the Essen Stroke Risk Score (ESRS). MATERIALS AND METHODS: This prospective study screened 151 patients with recent ischemic stroke and carotid atherosclerotic plaques at our hospital between August 2020 and December 2020. A total of 149 eligible patients underwent carotid CEUS, and 130 patients who were followed up for 15-27 months or until stroke recurrence were analyzed. Plaque enhancement on CEUS was investigated as a possible risk factor for stroke recurrence and as a possible adjunct to ESRS. RESULTS: During follow-up, 25 patients (19.2%) experienced recurrent stroke. Patients with plaque enhancement on CEUS had an increased risk of stroke recurrence events (22/73, 30.1%) compared to those without plaque enhancement (3/57, 5.3%), with an adjusted hazard ratio (HR) of 38.264 (95% confidence interval [CI]:14.975-97.767; P < 0.001) according to a multivariable Cox proportional hazards model analysis, indicating that the presence of carotid plaque enhancement was a significant independent predictor of recurrent stroke. When plaque enhancement was added to the ESRS, the HR for stroke recurrence in the high-risk group compared to that in the low-risk group (2.188; 95% CI, 0.025-3.388) was greater than that of the ESRS alone (1.706; 95% CI, 0.810-9.014). A net of 32.0% of the recurrence group was reclassified upward appropriately by the addition of plaque enhancement to the ESRS. CONCLUSION: Carotid plaque enhancement was a significant and independent predictor of stroke recurrence in patients with ischemic stroke. Furthermore, the addition of plaque enhancement improved the risk stratification capability of the ESRS.

Intrinsic Wave Velocity Propagation: A Novel Parameter for Assessing the Effect of Anthracycline Chemotherapy Agents on Cardiac Diastolic Function in Breast Cancer Patients.

OBJECTIVE: Anthracycline chemotherapeutic agents have significant cardiotoxicity. The present study emphasized the effect of anthracycline chemotherapy drugs on left ventricular (LV) myocardial stiffness in breast cancer patients by measuring the intrinsic wave velocity propagation (IVP), and evaluating the potential clinical value of IVP in detecting early LV diastolic function impairment. METHODS: A total of 68 newly diagnosed breast cancer patients, who were treated with anthracycline-based chemotherapy, were analyzed. Transthoracic echocardiography was performed at baseline (T0), and after 1, 2, 3, 4 and 8 chemotherapeutic cycles (T1, T2, T3, T4 and T5, respectively). Then, the IVP, LV strain parameters [global longitudinal strain (GLS), longitudinal peak strain rate at systole (LSRs), longitudinal peak strain rate at early diastole (LSRe), longitudinal peak strain rate at late diastole (LSRa), and the E/LSRe ratio], and conventional echocardiographic parameters were obtained and further analyzed. A relative reduction of >15% in GLS was considered a marker of early LV subclinical dysfunction. RESULTS: Compared to the T0 stage, IVP significantly increased at the T1 stage. However, there were no significant changes in GLS, LSRs, or LSRe between the T0 and T1 stages. These parameters significantly decreased from the T2 stage. LSRa started to significantly decrease at the T5 stage, and the E/LSRe ratio started to significantly increase at the T3 stage (all P<0.05). At the T0 stage, IVP (AUC=0.752, P<0.001) had a good predictive value for LV subclinical dysfunction after chemotherapy. CONCLUSIONS: IVP is a potentially sensitive parameter for the early clinical assessment of anthracycline-related cardiac diastolic impairment.

Quantitative Assessment of Right Ventricular Function in Patients With Systemic Lupus Erythematosus Using the Novel Non-invasive Pressure-Strain Loop.

OBJECTIVE: Current echocardiography evaluation of right ventricular (RV) function, which heralds the prognosis in patients with systemic lupus erythematosus (SLE), is of limited utility. The non-invasive pressure-strain loop (PSL), an emerging technique, has been found to feasible, sensitive and accurate in the diagnosis of cardiovascular diseases. The aim of this study was to quantitatively evaluate, using the non-invasive PSL, the right ventricular myocardial work (RVMW) in SLE patients. METHODS: Seventy-five SLE patients were recruited and grouped by pulmonary artery systolic pressure (PASP) into normal (group A, N = 26), mild (group B, N = 22) and moderate to severe (group C, N = 27) groups. Twenty-five healthy volunteers undergoing physical examination were recruited as the control group. Right ventricular global myocardial work index (RVGWI), global constructive work (RVGCW), global wasted work (RVGWW), global work efficiency (RVGWE), global longitudinal strain (RVGLS) and other conventional parameters were measured. DISCUSSION: There were no differences between group A and the control group with respect to RVLS, RVGLS and all RVMW parameters (all p values > 0.05). RVGWI and RVGCW significantly differed among the other groups (all p values < 0.05). RVGWE was significantly lower and RVGWW was significantly higher in group C than in the control group and groups A and B (all p values < 0.05). Compared with the control group, RVGWW was significantly increased and RVGLS was significantly decreased in group B (all p values < 0.05). All but one RVMW parameter moderately to strongly correlated with SLE disease activity index (SLEDAI) and World Health Organization Functional Class (WHO-FC). RVGWW (area under the receiver operating characteristic curve [AUC] = 0.893) and RVGWE (AUC = 0.877) were sensitive parameters in detecting earlier cardiac dysfunction in SLE patients. CONCLUSION: RVGWW and RVGWE serve as sensitive and promising parameters in the integrative analysis of early right ventricular dysfunction in SLE patients. To conclude, non-invasive PSL, the novel method, facilitates the quantitative assessment of RVMW in SLE patients.

Evaluation of subtle myocardial noncompaction by contrast echocardiography in patients with hypertrophic cardiomyopathy and its relationship with regional ventricular systolic dysfunction.

OBJECTIVES: Ourstudy was undertaken to analyze the impact of subtle noncompaction of the left ventricle on regional left ventricular function in patients with hypertrophic cardiomyopathy. METHODS: Speckle-tracking imaging and contrast echocardiography were performed in 40 patients with hypertrophic cardiomyopathy. Subtle noncompaction of the left ventricle was defined as myocardium with more than 3 trabeculations in a single imaging plane with a noncompaction to compaction ratio of greater than 0.4 and less than 2.0. RESULTS: Among 647 segments, noncompaction was present in 46 segments (7%) in the left ventricular apex in 18 patients (45%) on the standard 2-dimensional echocardiograms and in 181 segments (27%) in 32 patients (80%) on the contrast-enhanced images. The mean number of segments affected by noncompaction ± SD was 6 ± 2. The mean noncompacted thickness was 5.6 ± 0.2 mm, and the ratio of the noncompacted to compacted layers was 1.1 ± 0.4 on the contrast-enhanced images. The global peak systolic longitudinal strain in patients with hypertrophic cardiomyopathy with noncompaction (-12.8% ± 2.8%) had a significantly lower absolute value than that in patients with hypertrophic cardiomyopathy without noncompaction (-17.4% ± 1.5%; P < .05) and healthy control participants (-20.6% ± 1.3%; P < .05). The number of segments with noncompaction and the interventricular septal thickness were both independent predictors of the global peak systolic longitudinal strain. CONCLUSIONS: Contrast echocardiography is superior to standard 2-dimensional echocardiography for detecting subtle noncompaction in patients with hypertrophic cardiomyopathy. We found that the global peak systolic longitudinal strain in patients with hypertrophic cardiomyopathy with noncompaction had a significantly lower absolute value than that in patients without noncompaction and healthy controls, indicating that the total number of segments affected by coexistent subtle noncompaction in patients with hypertrophic cardiomyopathy was an independent predictor of left ventricular systolic dysfunction.

A novel hybrid transformer-CNN architecture for environmental microorganism classification.

The success of vision transformers (ViTs) has given rise to their application in classification tasks of small environmental microorganism (EM) datasets. However, due to the lack of multi-scale feature maps and local feature extraction capabilities, the pure transformer architecture cannot achieve good results on small EM datasets. In this work, a novel hybrid model is proposed by combining the transformer with a convolution neural network (CNN). Compared to traditional ViTs and CNNs, the proposed model achieves state-of-the-art performance when trained on small EM datasets. This is accomplished in two ways. 1) Instead of the original fixed-size feature maps of the transformer-based designs, a hierarchical structure is adopted to obtain multi-scale feature maps. 2) Two new blocks are introduced to the transformer's two core sections, namely the convolutional parameter sharing multi-head attention block and the local feed-forward network block. The ways allow the model to extract more local features compared to traditional transformers. In particular, for classification on the sixth version of the EM dataset (EMDS-6), the proposed model outperforms the baseline Xception by 6.7 percentage points, while being 60 times smaller in parameter size. In addition, the proposed model also generalizes well on the WHOI dataset (accuracy of 99%) and constitutes a fresh approach to the use of transformers for visual classification tasks based on small EM datasets.

Evaluation of Left Ventricular Function by Three-Dimensional Speckle-Tracking Echocardiography in Patients with Chronic Kidney Failure.

OBJECTIVE: To establish a quantitative evaluation of the left ventricle's systolic function in patients with chronic kidney failure (CKF) by three-dimensional speckle-tracking echocardiography. METHODS: Two-dimensional and three-dimensional transthoracic echocardiography was performed on 30 patients with CKF. The ejection fraction, mass and global peak longitudinal strain, global circumferential strain, global area strain, and global radial strain of the left ventricle were calculated. RESULTS: The ejection fraction, mass and global peak longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) in the CKF group were significantly lower than those in the control group. Simultaneously, the GLS, GCS, GAS and GRS were well correlated with the ejection fraction. For patients with normal ejection fraction in the CKF group, the GLS, GCS, GAS and GRS were lower than those in the control group, while the left ventricular mass was significantly higher in CKF patients than in the control group. For patients with hypertension in the CKF group, ejection fraction, GLS, GCS, GAS and GRS calculated using three-dimensional echocardiography were significantly lower than those in patients with normal blood pressure; however, the myocardial mass was higher. CONCLUSIONS: The parameters (GLS, GCS, GAS and GRS) calculated using three-dimensional speckle-tracking software were lower in the CKF group. Simultaneously, the left ventricular mass was higher in CFK patients than in the control group, thus showing that the myocardial contraction function was impaired and that myocardial remodeling had occurred.

Relation of Carotid Plaque Features Detected with Ultrasonography-Based Radiomics to Clinical Symptoms.

Carotid plaque is one of the predominant causes of stroke. We sought to build a nomogram using ultrasonography (US)-based radiomics and clinical features for identification of symptomatic carotid plaques. We prospectively enrolled 548 patients (mean age ± standard deviation, 63 ± 10 years; 373 men) were randomly divided into training and test cohorts. Clinical and conventional US features of carotid plaques were used to generate a clinical and conventional US model. US-based radiomics model was constructed by extracting radiomics features from grayscale and strain elasticity images. Multivariate logistic regression was performed using the radiomics scores together with clinical and conventional US data, and a final nomogram was subsequently developed. The performance of the final nomogram was assessed with respect to discrimination and clinical usefulness in the training of the test cohorts and contrast-enhanced US test cohort. All the radiomics scores were significantly higher in patients with symptomatic carotid plaques. The US-based radiomics model [area under the curve (AUC) = 0.930 and 0.922 for training and test cohorts, respectively] and final nomogram (AUC = 0.927 and 0.919, respectively) outperformed the clinical and conventional US model (AUC = 0.723 and 0.580, respectively). The decision curve analysis indicated that the final nomogram was clinically useful. In patients undergoing the contrast-enhanced US, the prevalence of plaque enhancement was higher in high-risk patients than in low-risk patients based on the final nomogram-score (P = 0.008). Nomogram has a high diagnostic performance for identification of symptomatic carotid plaques.

Persistent Endothelial Dysfunction in Coronavirus Disease-2019 Survivors Late After Recovery.

BACKGROUND: Coronavirus disease 2019 (COVID-19) can result in an endothelial dysfunction in acute phase. However, information on the late vascular consequences of COVID-19 is limited. METHODS: Brachial artery flow-mediated dilation (FMD) examination were performed, and inflammatory biomarkers were assessed in 86 survivors of COVID-19 for 327 days (IQR 318-337 days) after recovery. Comparisons were made with 28 age-matched and sex-matched healthy controls and 30 risk factor-matched patients. RESULTS: Brachial artery FMD was significantly lower in the survivors of COVID-19 than in the healthy controls and risk factor-matched controls [median (IQR) 7.7 (5.1-10.7)% for healthy controls, 6.9 (5.5-9.4)% for risk factor-matched controls, and 3.5(2.2-4.6)% for COVID-19, respectively, p < 0.001]. The FMD was lower in 25 patients with elevated tumor necrosis factor (TNF)-α [2.7(1.2-3.9)] than in 61 patients without elevated TNF-α [3.8(2.6-5.3), p = 0.012]. Furthermore, FMD was inversely correlated with serum concentration of TNF-α (r = -0.237, p = 0.007). CONCLUSION: Survivors of COVID-19 have a reduced brachial artery FMD, which is inversely correlated with increased serum concentration of TNF-α. Prospective studies on the association of endothelial dysfunction with long-term cardiovascular outcomes, especially the early onset of atherosclerosis, are warranted in survivors of COVID-19.

Constraints and tests of the OPERA superluminal neutrinos.

The superluminal neutrinos detected by OPERA indicate Lorentz invariance violation (LIV) of the neutrino sector at the order of 10(-5). We study the implications of the result in this work. We find that such a large LIV implied by OPERA data will make the neutrino production process π → µ + ν(µ) kinematically forbidden for a neutrino energy greater than about 5 GeV. The OPERA detection of neutrinos at 40 GeV can constrain the LIV parameter to be smaller than 3×10(-7). Furthermore, the neutrino decay in the LIV framework will modify the neutrino spectrum greatly. The atmospheric neutrino spectrum measured by the IceCube Collaboration can constrain the LIV parameter to the level of 10(-12). The future detection of astrophysical neutrinos of galactic sources is expected to be able to give an even stronger constraint on the LIV parameter of neutrinos.

Normalized Cardiac Structure and Function in COVID-19 Survivors Late After Recovery.

Background: Coronavirus disease 2019 can result in myocardial injury in the acute phase. However, information on the late cardiac consequences of coronavirus disease 2019 (COVID-19) is limited. Methods: We conducted a prospective observational cohort study to investigate the late cardiac consequences of COVID-19. Standard echocardiography and myocardial strain assessment were performed, and cardiac blood biomarkers were tested in 86 COVID-19 survivors 327 days (IQR 318-337 days) after recovery. Comparisons were made with 28 age-matched and sex-matched healthy controls and 30 risk factor-matched patients. Results: There were no significant differences in all echocardiographic structural and functional parameters, including left ventricular (LV) global longitudinal strain, right ventricular (RV) longitudinal strain, LV end-diastolic volume, RV dimension, and the ratio of peak early velocity in mitral inflow to peak early diastolic velocity in the septal mitral annulus (E/e') among COVID-19 survivors, healthy controls and risk factor-matched controls. Even 26 patients with myocardial injury at admission did not have any echocardiographic structural and functional abnormalities. There were no significant differences among the three groups with respect to serum concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin I (cTnI). Conclusion: This study showed that COVID-19 survivors, including those with myocardial injury at admission and those with severe and critical types of illness, do not have any echocardiographic evidence of cardiac structural and functional abnormalities 327 days after diagnosis.

Correlation of carotid plaque neovascularization detected by using contrast-enhanced US with clinical symptoms.

PURPOSE: To determine the correlation between the degree of plaque enhancement with contrast agent microbubbles and clinical symptoms in patients with carotid atherosclerotic plaque. MATERIALS AND METHODS: The study was approved by the hospital ethical committee, and informed consent was obtained from all patients. One hundred four patients (83 men: mean age, 64 years +/- 9 [standard deviation]; 21 women: mean age, 61 years +/- 10) with carotid plaques were studied with standard and contrast material-enhanced ultrasonography (US). Contrast enhancement in the plaque was evaluated with visual interpretation and quantitative analysis. RESULTS: Among the 104 patients, 35 (34%) had transient ischemic attack and/or cerebrovascular ischemic stroke. Plaque enhancement was found in 28 (80%) of 35 symptomatic patients and in 21 (30%) of 69 asymptomatic patients (P < .001). Enhanced intensity in the plaque (13.9 dB +/- 6.4) and the ratio of enhanced intensity in the plaque to that in the lumen of the carotid artery (0.54 +/- 0.23) in symptomatic patients were significantly greater than those in asymptomatic patients (8.8 dB +/- 5.2 [P < .001] and 0.33 +/- 0.19 [P < .001], respectively). Sensitivity and specificity were 74% and 62%, respectively, for enhanced intensity in the plaque (cutoff value, 10.0 dB) and 74% and 75%, respectively, for ratio of enhanced intensity in the plaque to that in the lumen of the carotid artery (cutoff value, 0.46). CONCLUSION: Symptomatic patients had more intense contrast agent enhancement in the plaque than asymptomatic patients, suggesting that contrast-enhanced carotid US may be used for plaque risk stratification.

Evaluation of myocardial strain and aortic elasticity in patients with bicuspid aortic valve.

This study evaluated the myocardial strain and aortic elasticity in patients with bicuspid aortic valve (BAV) and then investigated the relation between them. Thirty-nine patients (30 males; mean age 44±19 years; range 6 to 75 years) with BAV were recruited as BAV group, and 29 age- and sex-matched healthy controls (21 males; mean age 42±11 years; range 20 to 71 years) served as control group. Aortic strain, distensibility and stiffness index were derived using M-mode echocardiography. Left ventricular global myocardial strain was acquired with speckle-tracking echocardiography. Correlation between aortic elasticity and myocardial strain was also analyzed. The results showed that aortic stiffness was higher (17.5±14.0 vs. 5.3±2.7, P<0.001), and aortic strain (4.9±4.7 vs. 11.0±4.1, P<0.001) and distensibility (1.8±2.1 vs. 3.7±1.6, P<0.001) were lower significantly in BAV group than in control group. Global circumferential strain (-19.1±4.2 vs.-22.5±3.7, P<0.001), radial stain (29.8±14.9 vs. 38.0±8.8, P<0.001) and longitudinal stain (-18.4±3.4 vs.-20.8±3.5, P<0.001) were significantly lower in BAV group than in control group. There was weak association between aortic elasticity and myocardial strain. These findings indicated BAV patients manifest reduced myocardial strain which had weak relationship with aortic elastic lesion.

Evaluation of myocardial strain and artery elasticity using speckle tracking echocardiography and high-resolution ultrasound in patients with bicuspid aortic valve.

Reduced artery elasticity and reduced myocardial strain were present in patients with bicuspid aortic valve (BAV). Their relation to dilation of proximal aorta is unclear. We aimed to study their relation to dilation of proximal aorta. We studied 57 BAV patients categorized into 2 subgroup according to proximal ascending aortic dimensions (nondilated <35 mm and dilated ≥35 mm). Twenty-nine healthy subjects were recruited as control. Aortic and carotid strain, distensibility and stiffness index were derived. Left ventricular myocardial strain were acquired with speckle-tracking echocardiography. BAV patients with dilation of proximal ascending aorta had lower aortic strain (4.1 ± 4.2 % vs. 7.1 ± 3.5 %) and carotid strain (4.8 ± 1.9 % vs. 10.6 ± 4.2 %), lower aortic distensibility (1.4 ± 1.5 cm(2) dyn(-1) 10(-6) vs. 2.5 ± 1.5 cm(2) dyn(-1) 10(-6)) and carotid distensibility (1.6 ± 0.7 cm(2) dyn(-1) 10(-6) vs. 3.9 ± 2.4 cm(2) dyn(-1) 10(-6)), higher aortic stiffness index (19.7 ± 14.1 vs. 8.3 ± 4.9) and carotid stiffness index (12.2 ± 8.5 vs. 5.0 ± 2.2), and lower global circumferential (-15.9 ± 5.8 % vs. -19.1 ± 4.1 %), radial (19.3 ± 11.6 % vs. 29.8 ± 14.9 %) and longitudinal (-15.7 ± 3.4 % vs. -18.4 ± 3.4 %) compared with those without dilation of proximal ascending aorta. All mean values are different to p < 0.05. Dilation of proximal ascending aorta is associated with more advanced reduction of aortic and carotid elasticity and myocardial strain in BAV patients, supporting the need for detailed and extensive vascular and cardiac surveillance in BAV patients.

Prevalence and associated factors of corneal blindness in Ningxia in northwest China.

AIM: To describe the prevalence and demographic characteristics of corneal blindness in an urban and rural region of Ningxia, located in the northwest part of China. METHODS: A stratified, randomized sampling procedure was employed in the study, including urban and rural area of all age group. Visual acuity, anterior segment and ocular fundus were checked. Related factor of corneal disease, including age, gender, education status, ethnic group, location and occupation, were identified according to uniform customized protocol. An eye was defined to be corneal blindness if the visual acuity was <20/400 due to a corneal disease. RESULTS: Three thousand individuals (1290 from urban area and 1710 from rural area) participated in the investigation, with a response rate of 80.380%. The prevalence of corneal blindness was 0.023% in both eyes and 0.733% in at least one eye. The blindness in at least one eye with varied causes was present in 106 participants (3.533%) and in bilateral eyes in 34 participants (1.133%). The corneal diseases accounted for 20.754% of blindness in at least one eye and 20.588% of bilateral blindness. The prevalence of corneal disease was higher in older and Han ethnic group, especially those who occupied in agriculture and outdoor work. People with corneal blindness were more likely to be older and lower education. Rural population were more likely to suffer from bilateral corneal blindness than the urban population in ≥59-year group (χ (2)=6.716, P=0.019). Infectious, trauma and immune corneal disease were the three leading causes of corneal disease. Trauma corneal disease was more likely leading to blindness in one eye. However, infectious and immune corneal diseases make more contribution to the bilateral corneal blindness. CONCLUSION: Corneal blindness is a significant burden of in Ningxia population, encompassing a variety of corneal infections and trauma; the majority of those were avoidable. Health promotion strategies and good hygienic conditions have to be developed.