Use of speckle-tracking echocardiography to stratify risk of atrial fibrillation-related stroke: comparison of left atrial and atrial appendage mechanics

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): the National Natural Science Foundation of China

onbehalf

Sir Run Run Shaw Hospital,Zhejiang University,School of Medicine

Background

Left atrial (LA) and appendage (LAA) dysfunction were associated with increased risk of stroke in atrial fibrillation. However, usefulness of LA and LAA mechanics has not been fully compared. Methods:201 AF patients were prospectively enrolled. 42(20.8%) had previous stroke/TIA.  Speckle tracking was used to measure LA and LAA peak postive strain. LA and LAA MD was defined as the SD of time to peak positive strain corrected by the R-R interval. Results:LA MD and LAA MD were independently associated with stroke/TIA. The model based on CHA2DS2-VASc score for discrimination of stroke was significantly improved by adding LA MD or LAA MD (P < 0.01). Diagnostic value of LA MD was better than LAA MD in patients with normal LA volumes, while LAA MD was more useful in patients with LA enlargement.Conclusion:Both LA and LAA mechanics had incremental value over CHA2DS2VASc score. However, priorities of strain assessment depend on patients’ LA volume.

Variables Univariate analysis Multivariate analysis Model 1 Model 2 Model 3 OR (95% CI) P value OR (95% CI) P value OR (95% CI) p value OR (95% CI) P value Clinical parameters Age 1.09(1.04-1.14) <0.001 1.11(1.04-1.17) 0.001 1.11(1.05-1.17) 0.001 1.11(1.04-1.17) 0.001 BMI 0.988(0.89-1.10) 0.84 1.07(0.92-1.25) 0.40 1.07(0.91-1.25) 0.40 CHA2DS2-VASc score 1.52(1.15-2.00) 0.003 1.08(0.67-1.74) 0.76 1.08(0.65-1.80) 0.77 1.10(0.69-1.76) 0.69 Persistent AF 1.88(0.94-3.74) 0.07 0.75(0.23-2.40) 0.63 0.87(0.27-2.81) 0.82 Therapeutic anticoagulation 0.56(0.28-1.11) 0.10 0.22(0.09-0.57) 0.002 0.23(0.09-0.59) 0.002 0.22(0.09-0.57) 0.002 LA parameters LAEF 0.96(0.94-0.99) 0.002 0.982(0.953-1.01) 0.26 iLAVmin 1.03(1.01-1.05) 0.006 0.98(0.94-1.02) 0.27 LA MD 1.22(1.10-1.36) <0.001 1.16(1.02-1.32) 0.02 1.18(1.03-1.34) 0.02 1.16(1.02-1.32) 0.02 LA GLS 0.935(0.893-0.98) 0.005 1.0(0.953-1.14) 0.36 1.02(0.94-1.12) 0.59 1.02(0.94-1.10) 0.72 LAA parameters LAAEV 0.12(0.02-0.74) 0.02 3.34(0.31-36.06) 0.32 LAA EF 0.98(0.96-1.00) 0.06 1.01(0.98-1.04) 0.65 LAA GLS 0.85(0.77-0.94) 0.001 0.96(0.86-1.07) 0.46 0.97(0.87-1.08) 0.59 0.96(0.87-1.06) 0.44 LAA dense SEC/thrombus 3.12(1.39-6.99) 0.006 2.02(0.75-5.45) 0.167 LAA MD 1.19(1.09-1.29) <0.001 1.19(1.08-1.31) 0.001 1.19(1.08-1.31) 0.001 1.19(1.08-1.31) 0.001 Univariable and multivariable logistic regression analyses of associations between clinical and echocardiographic covariates with stroke Abstract Figure.

[Development of a hyperkalemia risk assessment model for patients with chronic kidney disease]

Objective: To investigate risk factors for hyperkalemia among chronic kidney disease (CKD) patients and establish a risk assessment model for predicting hyperkalemia events. Methods: Clinical data of CKD patients (stage 3 to 5) hospitalized between May 2017 and June 2020 from 14 hospitals were retrospectively collected and divided into training dataset and validation dataset through balanced random sampling. Multivariate logistic regression analysis was used to analyze risk factors for hyperkalemia in CKD patients and the factors were scored. Receiver operating characteristic (ROC) curve was plotted and the area under the curve (AUC) was calculated. Meanwhile, the cut-off value with the best sensitivity and specificity were used to verify the accuracy of the model in validation dataset. Results: A total of 847 CKD patients were enrolled and further divided into training dataset (n=675) and validation dataset (n=172). There were 555 males and 292 females, with a mean age of (57.2±15.6) years. Multivariate logistic regression analysis showed that age, CKD stage, history of heart failure, history of serum potassium ≥5.0 mmol/L, diabetes, metabolic acidosis, and use of medications that increase serum potassium levels were risk factors for causing hyperkalemia in patients with CKD. Risk assessment model was established based on these risk factors. The AUC of the ROC curve was 0.809. Using 4 as the cut-off value, the sensitivity and specificity for predicting hyperkalemia events reached 87.1% and 57.0%, respectively. Conclusion: The model established in the current study can be used for predicting hyperkalemia events in clinical practices, which offers a new way to optimize serum potassium management in patients with CKD.

Testicular hypertrophy as predictor of contralateral nonpalpable testis among Chinese boys: An 18-year retrospective study

OBJECTIVE

To assess the accuracy of contralateral testis hypertrophy for predicting the fate of nonpalpable testis in Chinese boys at different ages.

METHODS

The data of patients who presented with unilateral impalpable testis and who underwent laparoscopy at the Children's Hospital of Chongqing Medical University between January 1, 2000 and January 1, 2018 were reviewed. The boys were divided into four groups: age-matched volunteers with no testicular abnormalities represented the control group (group I), boys with palpable undescended testis (group II), boys with nonpalpable testis (NPT)/viable testis (VT) (group III), and boys with NPT/non-viable testis (NVT) group (group IV). Scrotal testes were prospectively measured by ultrasonography for volume and size, and diagnostic laparoscopy was performed to determine the state of the cryptorchid testis.

RESULTS

The mean contralateral testicular volume and length in the boys with an absent testis was 0.78mL and 17mm compared with 0.67mL and 15mm in the boys with a testis present and 0.63mL and 15mm in the controls, respectively (P<0.05). The predictive accuracy, sensitivity, and specificity for an absent testis were 64.9%, 75%, and 49%, respectively, for volume and 64.2%, 56.3%, and 76.4%, respectively for length at the optimal cutoff value of 0.65mL volume and 16.55mm length. Contralateral testis volume was the most accurate in predicting monorchism in 0-2-year-olds (sensitivity: 75%, specificity: 70%, accuracy: 73.1%) and the contralateral testicular length was most accurate for 4-6-years-old (sensitivity: 68.6%; specificity: 77.8%; accuracy: 72.2%). We also included 29 patients with bilateral undescended testis (UDT) and with unilateral nonpalpable. Cutoff values for testicular volume and length were 0.6mL (sensitivity: 81.8%, specificity: 88.9%, accuracy: 86.2%) and 13.5mm (sensitivity: 63.6%, specificity: 77.8%, accuracy: 77.8%).

CONCLUSION

The present results exclusively obtained from laparoscopic exploration suggest that a testis volume of>0.65mL or a testis length of>16.55mm could predict monarchism with an accuracy of about 65%. In younger patients aged 0-2 years and 4-6 years, the overall predictive accuracy increases to about 73% but laparoscopic exploration is still required.

Small RNA sequencing reveals miRNAs important for hypoxic adaptation in the Tibetan chicken

1. The Tibetan chicken, which is an indigenous breed living on the Tibetan Plateau, exhibits hypoxic adaptations to its high-altitude environment. However, the molecular mechanism behind this hypoxic adaptation is still unclear. This study aimed to investigate differentially expressed miRNAs involved in hypoxic adaptation through high-throughput RNA sequencing. 2. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to verify the differentially expressed miRNAs and their target genes in chicken embryonic heart tissues and fibroblasts. Luciferase reporter assays were performed to confirm the relationship between miRNAs and target genes. 3. The study identified 37 differentially expressed miRNAs in Tibetan chicken embryonic heart tissues, including 20 up- and 17 down-regulated miRNAs, compared to those found in lowland chickens. Differentially expressed miRNAs were mainly involved in biological processes, such as cell cycle arrest, toll-like receptor signalling pathways, and I-kappa B kinase/NF-kappa B signalling. The data showed that gga-miR-34 c-5p was significantly upregulated in Tibetan chicken tissues and hypoxic fibroblasts, while EHHADH, a target gene of gga-miR-34 c-5p, was downregulated. Moreover, gga-miR-34 c-5p dramatically decreased the luciferase activity of the wild EHHADH, whereas no effect on the mutational EHHADH was found. 4. This study identified miRNA expression profiles in the Tibetan chicken and suggested that miR-34 c-5p acts as a novel miRNA associated with hypoxic adaptation. This facilitates the understanding of molecular mechanisms that underlie long-term exposure to hypoxia.

[Analysis on the situation of being supported by the national natural science foundation of China in the field of occupational diseases from 2010 to 2019]

Objective: To understand the situation supported by the National Natural Science Foundation in the field of occupational diseases (H2402) in China, so as to provide a reference basis for the application and research of scientific researchers in the field of occupational diseases in China. Methods: The information system of scientific and technological achievements was used to search the financial support of the National Natural Science Foundation of China (NSFC) in the field of occupational diseases from 2010 to 2019. Results: From 2010 to 2019, a total of 55 projects were funded under the Occupational Disease code (H2402) , with a total funding of 22.33 million yuan, of which 30 were supported by the Youth Science Foundation, 20 by the Youth Science Foundation and 5 by the Regional Science Foundation. Thirty five items of the research projects focused on pneumoconiosis and other respiratory diseases which accounted for 63.64 per cent. Forty one items of scientific research projects are supported by domestic institutions of higher learning which accounted for 74.55 per cent. Conclusion: The research support of the National Natural Science Foundation of China to the field of occupational diseases (H2402) has increased steadily, but the support of different research directions and supporting units is not balanced. It is suggested that departments concerned strengthen guidance and support for the applicants in less developed areas and weak research directions of the projects in the National Natural Science Foundation.

Oropharyngeal Secretion as Alternative for SARS-CoV-2 Detection

This study aimed to determine if sampling of oropharyngeal secretions (OSs) helps improves detection of SARS-CoV-2 RNA by nucleic acid amplification testing of potential patients with COVID-19. The first prospective study consisted of 75 patients with COVID-19 who were ready for discharge and who had 2 consecutive negative results per nucleic acid amplification testing (NAAT) of viral samples retrieved with nasopharyngeal swabs (NPSs). Because of detection of potential false negatives in that cohort, the NAAT results of paired OS and NPS samples from 50 additional recruits with COVID-19 during their recovery stage were used in a second prospective study to compare the diagnostic values of the 2 viral RNA sampling methods. For identification of the frequency of inconsistency between the sampling methods, the McNemar's test was used for difference analysis and the kappa statistic for consistency analysis. OSs obtained from 2 of the 75 participants in the first study yielded positive results for SARS-CoV-2 nucleic acid. Both were male and aged >60 y. Subsequent chemiluminescence enzyme immunoassays indicated that they were positive for the SARS-CoV-2 IgM and IgG antibodies. For parallel NAAT of OS and NPS samples in the second study, McNemar's test indicated that the difference between the frequencies of inconsistent parts of OS and NPS was statistically significant (P = 0.021). Cohen's kappa coefficient for OS and NPS was 0.244, which is indicative of fair consistency. The NPS test has a risk of sending home more patients (59%) who still have the infection, while the OS test will make such an error in fewer patients (14%). Although OS sampling improves the accuracy of SARS-CoV-2 nucleic acid testing, it has to be emphasized that this conclusion is based on a very small sample size. Detection of viral RNA from a patient's secretions is not confirmative of viral infectivity.

Strategies and prospects of effective neural circuits reconstruction after spinal cord injury

Due to the disconnection of surviving neural elements after spinal cord injury (SCI), such patients had to suffer irreversible loss of motor or sensory function, and thereafter enormous economic and emotional burdens were brought to society and family. Despite many strategies being dealing with SCI, there is still no effective regenerative therapy. To date, significant progress has been made in studies of SCI repair strategies, including gene regulation of neural regeneration, cell or cell-derived exosomes and growth factors transplantation, repair of biomaterials, and neural signal stimulation. The pathophysiology of SCI is complex and multifaceted, and its mechanisms and processes are incompletely understood. Thus, combinatorial therapies have been demonstrated to be more effective, and lead to better neural circuits reconstruction and functional recovery. Combinations of biomaterials, stem cells, growth factors, drugs, and exosomes have been widely developed. However, simply achieving axon regeneration will not spontaneously lead to meaningful functional recovery. Therefore, the formation and remodeling of functional neural circuits also depend on rehabilitation exercises, such as exercise training, electrical stimulation (ES) and Brain-Computer Interfaces (BCIs). In this review, we summarize the recent progress in biological and engineering strategies for reconstructing neural circuits and promoting functional recovery after SCI, and emphasize current challenges and future directions.

[Whole exome sequencing and analysis of a Chinese family with familial pulmonary sarcoidosis]

Objective: To analyze the clinical features and the results of the whole exome sequencing (WES) of a Chinese family containing both pulmonary sarcoidosis patients and healthy members, and to find potent genes and variants that may be involved in the pathogenesis of sarcoidosis. Methods: Three patients with pulmonary sarcoidosis and 1 healthy member was included from a Chinese Han family in the north of China diagnosed in November 2016, which characterized as 2 consecutive generations including 2 males and 1 female, aged from 23 to 69 years old. The proband is Ⅱ-6. Pulmonary sarcoidosis was diagnosed by clinical features, imaging and pathological findings, and clinical data such as family history were collected. Whole blood samples were taken and WES (Illumina NovaSeq S2) was performed. The pathogenicity analysis and gene annotation analysis were performed by ExAC, SIFT, Polyphenv2, Metascape databases. Results: It was found that 27 genes were highly pathogenic in the database filtering result. After gene annotation analysis, we found that ZC3H12A gene can negatively regulate the differentiation of Th17 cells, which may be involved in the onset of pulmonary sarcoidosis. Sanger sequencing confirmed the c.1361 A>G variant in 3 sarcoidosis patients but normal in healthy member. Conclusions: In patients with familial pulmonary sarcoidosis, the genetic background could regulate immune response which is one of the pathogenic mechanisms of sarcoidosis. The whole exome test and gene ontology analysis showed that Ⅱ-2, Ⅱ-6 and Ⅲ-1 pulmonary sarcoidosis patients in this family were all shared the same variant on ZC3H12A gene, which played a pivotal role in differentiation of Th17 cells and is a potent pathogenesis gene in this Chinese pulmonary sarcoidosis family.

P1360Association between left atrial appendage dysfunction and thromboembolic risk in nonvalvular atrial fibrillation

Abstract

Background/Introduction:  Atrial fibrillation (AF) is associated with higher risk for thromboembolism , and the discriminative ability of the widely used CHA2DS2-VASc scores for risk stratification is modest. Although the presence of thrombus in the LAA is the most powerful predictors for thromboembolic risk, they are often absent in patients with AF and prior stroke. AF may be related to myocardial fibrosis, and even though left atrial fibrosis is associated with mechanical dispersion, this phenomenon is not well studied in LAA. We hypothesized that detection of LAA dysfunction and mechanical dispersion using strain echocardiography is useful in the identification of cardiac thromboembolism.

Purpose

The aim of this study was to determine the association of LAA mechanics assessed using strain analysis with previous thromboembolic events in patients with nonvalvular AF and to assess the potential incremental significance of LAA mechanical dispersion over the traditional risk stratification scheme.

Methods

A group of 116 patients with AF referred for TEE was prospectively analyzed. LAA strain and mechanical dispersion in parallel with other conventional TEE parameters were analyzed in terms of their association with previous embolic stroke and peripheral embolization.

Results

Patients with embolic events had a higher mean CHA2DS2-VASc score, higher incidence of LAA dense SEC or thrombi, and other clinical data were comparable. Patients with embolic events had greater impairment in the LA standard parameters, and lower global and regional LAA longitudinal strain than those of the controls. LAA MD was significantly higher in patients with embolization than in those without it (18.91 ± 7.19 %vs 13.8 ± 5.54%; P &lt; .001). In ROC analysis, cut-off values for LAA MD,LAEF, LAA GLS for the presence of dense SEC/ thrombus were &gt;20.21 % (p = 0.0076), ≤31.11 % (p = 0.017), and ≤ 7.31 % (p = 0.014), respectively. LAA MD, LAEF, LAA thrombus and CHA2DS2-VASc scores were independently associated with the presence of thromboembolism in multivariate analyses, and LAA MD had additional significance over the CHA2DS2-VASc score.

Conclusion

LAA MD, LAA thrombi and LAEF had statistically significant meaning for the presence of prior embolism that was independent of the standard planimetric and volumetric measurements. What’s more, LAA MD had an incremental value over CHA2DS2-VASc score in risk stratification and warrants testing in a larger study.

Abstract Figure. ROC curves for LAA parameters

THU0544 MULTIMODAL PHOTOACOUSTIC/ULTRASONIC IMAGING SYSTEM: A NEW IMAGING METHOD FOR EVALUATING RA

Background:

Photoacoustic imaging (PAI), a new imaging technique which can be integrating with ultrasound (US) imaging, has shown potential in visualizing small joints. We have developed a multimodal photoacoustic/ultrasound (PA/US) imaging system, equipped with a handheld probe, which can provide dual-wavelength PA/US imaging to identify the micro-vessels of the inflamed articular regions and measure the oxygenation level of human inflamed synovium.

Objectives:

To validate the potential value for RA of the imaging system.

Methods:

A total of 32 RA patients received PA/US examination on seven small joints (MCP2, MCP3, PIP2, PIP3, MTP2, MTP5, and wrist of the clinically dominant side). The 0-3 score was used to semi-quantify the PA and PD signals of the inflammatory articular lesions, and the sums of PA and PD scores (PA-sum and PD-sum) were utilized. The relative oxygen saturation (SO2) values of the inflamed regions were measured by calculating the ratio of PA signals at the wavelength of 750nm and 830nm. All the patients were classified to 3 PA+SO2 patterns (Pattern 1: no or minimal PA signals; Pattern 2: evident PA signals and hyperoxia; Pattern 3: evident PA signals and hypoxia). The correlations between imaging scores and laboratory data, as well as clinical scoring systems were assessed.

Results:

A total of 32 patients of RA were recruited aged from 25-71 years-old were examined. PD-sum had moderate correlation with the clinical scores (r=0.529, 0.546, 0.490, 0.493 for DAS28ESR, DAS28CRP, SDAI, CDAI), moderate correlations with TJC (r=0.575) and SJC (r=0.491), fair correlation with VAS (r=0.239), poor correlation with PGA (r=0.153), and moderate correlation with EGA (r=0.457). The PA-sum had substantial correlations with the clinical scores (r= 0.699, 0.746, 0.723, 0.736 for DAS28ESR, DAS28CRP, SDAI, CDAI), substantial correlations with TJC (r=0.787) and SJC (r=0.694), moderate correlations with VAS (r=0.544) and PGA (r=0.529), and substantial correlation with EGA (r=0.708).

Ten patients were classified as Pattern 1, 12 as Pattern 2, 9 as Pattern 3. The PA+ SO2 patterns presented substantial correlations with the clinical scores (DAS28ESR r=0.690, DAS28CRP r=0.782, SDAI r=0.805, CDAI r=0.799, SJC r=647, TJC r=0.676, respectively), substantial correlation with VAS (r=0.714), and moderate correlation with PGA (r=0.476) and EGA (r=0.502). Significant differences between those who were classified as hypoxia and hyperoxia with evident PA signals, were detected in VAS (p=0.020) and PGA (p=0.026).

Conclusion:

The PA-sum scores and the PA+SO2 patterns can be utilized as objective imaging parameters reflecting the disease activity of RA. PAI may serve as a supplement to conventional US examinations for RA patients.

References:

[1]Backhaus, M., et al., Evaluation of a novel 7-joint ultrasound score in daily rheumatologic practice: a pilot project. Arthritis Rheum, 2009. 61(9): p. 1194-201.

[2]Colebatch, A.N., et al., EULAR recommendations for the use of imaging of the joints in the clinical management of rheumatoid arthritis. Ann Rheum Dis, 2013. 72(6): p. 804-14.

Figure 1.

the photo of the multimodal PA/US imaging system

Figure 2.

an example of the PA/US imaging

Disclosure of Interests:

Chenyang Zhao: None declared, Qian Wang: None declared, Xixi Tao: None declared, Chen Yu: None declared, Sirui Liu: None declared, Mengtao Li: None declared, Xinping Tian: None declared, Zhenhong Qi: None declared, Jianchu Li: None declared, Fang Yang: None declared, Lei Zhu: None declared, Xiaofeng Zeng Consultant of: MSD Pharmaceuticals, Meng Yang: None declared, Yuxin Jiang: None declared

Graphene Oxide Enables the Reosteogenesis of Previously Contaminated Titanium In Vitro

The main goal of peri-implantitis treatment is to control infection and arrest bone loss, which requires the removal of polymicrobial biofilms on the implant surface and the reduction of tissue invasion. Additionally, prognosis can be improved if reosseointegration occurs on previously contaminated implants. To evaluate whether graphene oxide (GO) can remove polymicrobial biofilms, biofilms were established on titanium surfaces in vitro and treated with different methods: group B, removed only with brushing; group G, treated with different GO concentrations (64, 128, 256, and 512 μg/mL); group GB, combined treatments of groups B and G; and group C, untreated. Subsequently, to evaluate reosteogenesis on previously contaminated titanium, 4 groups were used: groups C, B, GB-256, and GB-512 (treated with 256 and 512 μg/mL of GO, respectively). Intact clean titanium (IC) was used as a control. Additionally, cell behavior on IC treated with GB-256 (IGB-256) and GB-512 (IGB-512) was compared with that of the GB-256 and GB-512 groups, respectively. The results showed that at high concentrations (≥256 μg/mL), GO eliminated residual bacteria and inhibited biofilm reformation after brushing, whereas neither GO nor brushing alone could achieve this. Bone marrow-derived mesenchymal stem cell viability in groups GB-256 and IC was higher than that in groups GB-512, C, and B (P < 0.05). No significant difference was found between group GB-256 and group IC (P > 0.05). Osteogenic differentiation of bone marrow-derived mesenchymal stem cells in group GB-256 was higher than that in groups IC, GB-512, C, and B. No difference was found between groups IGB-256 and IGB-512 and groups GB-256 and GB-512, respectively (P > 0.05). In conclusion, 256 μg/mL of GO combined with brushing significantly removed polymicrobial biofilms that remained on the previously contaminated titanium surfaces. The bone marrow-derived mesenchymal stem cell osteogenic potential was regained or even enhanced on the titanium surfaces treated this way in vitro, which might provide a new idea for treating peri-implantitis.

Evaluation of synuclein-γ levels by novel monoclonal antibody in saliva and cancer tissues from oral squamous cell carcinoma patients

The clinical value of synuclein-γ (SNCG) in oral squamous cell carcinoma (OSCC) was evaluated by detecting the expression of SNCG in saliva and tissues and its correlation with clinicopathological parameters (age, gender, ethnicity, degree of differentiation, clinical stage, and lymph node metastasis). Salivary samples were collected from 79 patients with OSCC, 31 patients with oral premalignant lesions (OPMLs), such as oral lichen planus, oral leukoplakia, and erythema, and 80 controls, and levels of SNCG in salivary samples were determined by enzyme-linked immunosorbent assay (ELISA). Tissue expression in formalin-fixed tissue biopsies of 94 cases of OSCC and 30 adjacent normal tissues was analyzed by immunohistochemistry (IHC) using an antibody against SNCG. The results showed that the salivary levels of SNCG in patients with OSCC and OPMLs were significantly higher than those detected in the control group (p<0.001). The immunohistochemical results showed that SNCG was highly expressed in tumor cells of OSCC patients, with low expression in the adjacent normal epithelium (p<0.001, OR=6.074). Salivary SNCG level correlated with differentiation (p=0.022). Besides, the expression of SNCG in OSCC tissues was also significantly associated with differentiation (p<0.001).