Low-intensity pulsed ultrasound treatment mitigates ventricular arrhythmias via inhibiting microglia-mediated neuroinflammation in heart failure rat model.

BACKGROUND: Sympathetic overactivation plays an important role in heart failure (HF)-induced ventricular arrhythmias (VAs). Microglia-mediated neuroinflammation could contribute to sympathetic overactivation. A previous study demonstrated that low-intensity pulsed ultrasound (LIPUS) could inhibit neuroinflammation. However, whether LIPUS could attenuate HF-induced VAs via inhibiting microglia-mediated neuroinflammation remains largely unknown. METHODS: Forth Sprague-Dawley male rats were averagely randomized into four groups: CTL (control) group, CTL + LIPUS group, HF group and HF + LIPUS. Surgical ligation of the coronary artery was used for induction of HF. In vivo electrophysiological study was performed to check VAs susceptibility. Left stellate ganglion (LSG) neural activity and heart rate variability (HRV) were used to test sympathetic nerve activity. RESULTS: Compared to the HF group, LIPUS treatment significantly ameliorated HF-induced cardiac hypertrophy, fibrosis, and dysfunction. In addition, LIPUS treatment markedly inhibited HF-induced VAs susceptibility and reversed gap junction remodeling. LIPUS treatment obviously inhibited microglial activation and neuroinflammation in PVN, sympathetic hyperactivity in the LSG and proinflammatory cytokines releases in the ventricle. P2X7/NLRP3 signaling pathway may be involved in the anti-arrhythmic effect of LIPUS treatment following HF. CONCLUSIONS: Our data demonstrated that LIPUS treatment protected against HF-induced VAs via alleviating microglia-mediated neuroinflammation, sympathetic overactivation and proinflammatory cytokines releases through inhibiting P2X7/NLRP3 signaling. This study provides novel insight into the therapeutic potential of LIPUS.

Macrophage-targeted ultrasound nanobubbles for highly efficient sonodynamic therapy of atherosclerotic plaques by modulating M1-to-M2 polarization.

BACKGROUND AND AIMS: Sonodynamic therapy (SDT) is a new approach for the treatment of atherosclerosis (AS), yet the poor targeting ability of sonosensitizers limits its therapeutic efficacy. Herein, we reported a plaque-targeted nanoplatform modified with macrophage type A scavenger receptor (SR-A)-targeted peptide (designated as SR-A-Ce6NB) to augment the efficacy of low-intensity pulsed ultrasound (LIPUS)-mediated SDT of atherosclerotic plaque. METHODS: SR-A-Ce6NB was fabricated by thin hydration method and biotin-avidin system, and its physicochemical properties, biocompatibility and plaque-targeting ability were investigated. RAW 264.7 cells were used for in vitro experimental studies. Male 6-week-old apolipoprotein E-deficient mice were fed a high-fat diet for 16 weeks to induce aortic atherosclerotic plaques. Plaque-bearing mice were randomly allocated into five groups (n = 6): control group, Ce6 + LIPUS group, Ce6NB + LIPUS group, SR-A-Ce6NB + LIPUS group and atorvastatin group. After treatment in each group, the aortic artery was harvested for Oil red O, H&E, Masson's trichrome staining, immunohistochemical and immunofluorescent staining. RESULTS: SR-A-Ce6NB with high stability and excellent biocompatibility was successfully fabricated. SR-A-Ce6NB could actively target activated macrophages and selectively accumulate in the plaque. SR-A-Ce6NB could be triggered by LIPUS and had a more potent sonodynamic effect than free Ce6 to potentiate SDT. SR-A-Ce6NB-mediated SDT enhanced the anti-atherogenic effect via modulating M1-to-M2 macrophage polarization and had an earlier onset of action on plaque than the statin-mediated effect. No apparent side effect was observed after intravenous SR-A-Ce6NB injection and LIPUS exposure. CONCLUSIONS: Macrophage-targeted nanoplatform SR-A-Ce6NB-mediated SDT provides a safe, effective and preferable anti-atherogenic therapy by mediating M1-to-M2 macrophage polarization.

Contribution quality evaluation of table tennis match by using TOPSIS-RSR method - an empirical study.

This paper aims to evaluate the contribution quality of table tennis matches comprehensively and explore the ranking characteristics of evaluation results and the rationality of grading. Through the application of the documentation method, videos, Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Rank Sum Ratio (RSR), the contribution quality evaluation index system of table tennis matches was established. After then, the technical and tactical performances of 38 matches between H (anonymous), who is currently highly concerned and active in the international table tennis world from 2018 to 2020 were comprehensively evaluated. According to research results, H had 8 matches with the Ci value > 0.5 in serve rounds, 4 with the Ci value > 0.5 in receive rounds, and 5 with the RSR value > 0.6 in the comprehensive strength. These findings were generally consistent with the final match results. Furthermore, Pearson Correlation showed that the three indicators were significantly correlated with competition performance (CP) (P < 0.01). Each race could be divided into four grades, and there was a very significant difference among them by variance test (F = 60.281, P < 0.01). Meanwhile, SNK pairwise comparison between four grades had statistical significance (P < 0.05). Therefore, researchers could conclude that the combination of TOPSIS and RSR could objectively and accurately reflect the contribution quality of table tennis matches. This method could be promoted and applied in the competition performance evaluation of other net games.

Automatic Myocardial Contrast Echocardiography Image Quality Assessment Using Deep Learning: Impact on Myocardial Perfusion Evaluation.

OBJECTIVE: The image quality of myocardial contrast echocardiography (MCE) is critical for precise myocardial perfusion evaluation but challenging for echocardiographers. Differences in quality may lead to diagnostic heterogeneity. This study was aimed at achieving automatic MCE image quality assessment using a deep neural network (DNN) and investigating its impact on myocardial perfusion evaluation. METHODS: The Resnet-18 model was used for training and testing on internal and external data sets. Quality assessment involved three aspects: left ventricular opacification (LVO), shadowing, and flash adequacy; the quality score was calculated based on image quality. This study explored the impact of the DNN-based quality score on perfusion evaluation (normal, delay or obstruction) by echocardiographers (two seniors, one junior and one novice). Additionally, the effect of the score difference between re-scans on perfusion evaluation was investigated. RESULTS: The time cost for DNN prediction was 0.045 s/frame. In internal validation and external testing, the DNN achieved F1 and macro F1 scores >90% for quality assessment and had high intraclass correlation coefficients (0.954 and 0.892, respectively) in sequence quality scores. The proportion of segments deemed uninterpretable increased as the DNN-based quality score decreased. The agreement of perfusion assessment between one senior and others decreased as the quality score decreased. And the greater the score difference between the re-scans, the lower was the agreement on perfusion assessment by the same echocardiographer. CONCLUSION: This study determined the effectiveness of DNN for real-time automatic MCE quality assessment. It has the potential to reduce the variability in perfusion evaluation among echocardiographers.

Ultrasound-controlled nano oxygen carriers enhancing cell viability in 3D GelMA hydrogel for the treatment of myocardial infarction.

Heart failure is a critical and ultimate phase of cardiovascular ailment that leads to a considerable incidence of disability and mortality. Among various factors contributing to heart failure, myocardial infarction is one of the most frequent and significant causes, which is still difficult to manage effectively. An innovative therapeutic strategy, namely a 3D bio-printed cardiac patch, has recently emerged as a promising approach to substitute damaged cardiomyocytes in a localized infarct region. Nevertheless, the efficacy of this treatment primarily relies on the long-term viability of the transplanted cells. In this study, we aimed to construct acoustically sensitive nano oxygen carriers to improve cell survival inside the bio-3D printed patch. In this study, we initially created nanodroplets capable of phase transition triggered by ultrasound and integrated them into GelMA (Gelatin Methacryloyl) hydrogels, which were then employed for 3D bioprinting. After adding nanodroplets and ultrasonic irradiation, numerous pores appeared inside the hydrogel with improved permeability. We further encapsulated hemoglobin into nanodroplets (ND-Hb) to construct oxygen carriers. Results of in vitro experiments showed the highest cell survival within the patch of ND-Hb irradiated by the low-intensity pulsed ultrasound (LIPUS) group. The genomic analysis discovered that the increased survival of seeded cells within the patch might be related to the protection of mitochondrial function owing to the improved hypoxic state. Eventually, in vivo studies revealed that the LIPUS+ND-Hb group had improved cardiac function and increased revascularization after myocardial infarction. To summarize, our study successfully improved the permeability of the hydrogel in a non-invasive and efficient manner, facilitating the exchange of substances in the cardiac patch. Moreover, ultrasound-controlled oxygen release augmented the viability of the transplanted cells and expedited the repair of infarcted tissues.

The 2-year postoperative left heart function in marginal donor heart recipients assessing by speckle tracking echocardiography.

This study analyzed the differences and explored the donor/recipient factors between marginal and standard donor heart recipients after heart transplantation (HT) by speckle tracking echocardiography (STE). Seventy-two HT patients were enrolled: 25 standard and 47 marginal donor heart recipients. Thirty HT patients completed 2-year continuous follow-up (1, 6, 12, 24 months). Thirty healthy volunteers were controls. STE was used to track the strain characteristics of the left ventricle and atrium for detecting early changes in marginal donor heart recipients, including left ventricular global longitudinal, circumferential and radial strain (LVGLS, LVGCS, LVGRS) and left atrial strain in systole (LAS-S) and late diastole (LAS-A). The perioperative parameters were similar between the standard and marginal groups. No significant differences were found in left heart size, systolic and diastolic function parameters. Left ventricular systolic strain (LVGLS, LVGCS, LVGRS) and systolic and late diastolic left atrial strain (LAS-S, LAS-A) were lower in the HT recipients than the control group (P < 0.05), but there was no difference between the marginal and standard groups (P > 0.05). LVGLS, LVGCS, and LAS-S were low in the marginal group 1 month after surgery but recovered gradually at 6 months. The patients with donor/recipient body weight ratio < 0.8 group had lower LVGLS and LAS-S. STE showed no significant difference between marginal and standard donor recipients. The LVGLS and LAS-S were lower in those with a smaller donor/recipient body weight ratio. The cardiac function of HT patients was lower in the early postoperative period but gradually recovered over time.

A novel risk stratification model for STEMI after primary PCI: global longitudinal strain and deep neural network assisted myocardial contrast echocardiography quantitative analysis.

Background: In ST-segment elevation myocardial infarction (STEMI) with the restoration of TIMI 3 flow by percutaneous coronary intervention (PCI), visually defined microvascular obstruction (MVO) was shown to be the predictor of poor prognosis, but not an ideal risk stratification method. We intend to introduce deep neural network (DNN) assisted myocardial contrast echocardiography (MCE) quantitative analysis and propose a better risk stratification model. Methods: 194 STEMI patients with successful primary PCI with at least 6 months follow-up were included. MCE was performed within 48 h after PCI. The major adverse cardiovascular events (MACE) were defined as cardiac death, congestive heart failure, reinfarction, stroke, and recurrent angina. The perfusion parameters were derived from a DNN-based myocardial segmentation framework. Three patterns of visual microvascular perfusion (MVP) qualitative analysis: normal, delay, and MVO. Clinical markers and imaging features, including global longitudinal strain (GLS) were analyzed. A calculator for risk was constructed and validated with bootstrap resampling. Results: The time-cost for processing 7,403 MCE frames is 773 s. The correlation coefficients of microvascular blood flow (MBF) were 0.99 to 0.97 for intra-observer and inter-observer variability. 38 patients met MACE in 6-month follow-up. We proposed A risk prediction model based on MBF [HR: 0.93 (0.91-0.95)] in culprit lesion areas and GLS [HR: 0.80 (0.73-0.88)]. At the best risk threshold of 40%, the AUC was 0.95 (sensitivity: 0.84, specificity: 0.94), better than visual MVP method (AUC: 0.70, Sensitivity: 0.89, Specificity: 0.40, IDI: -0.49). The Kaplan-Meier curves showed that the proposed risk prediction model allowed for better risk stratification. Conclusion: The MBF + GLS model allowed more accurate risk stratification of STEMI after PCI than visual qualitative analysis. The DNN-assisted MCE quantitative analysis is an objective, efficient and reproducible method to evaluate microvascular perfusion.

Low-intensity focused ultrasound guided dodecafluoropentane-loaded acoustic phase-change nanoparticles for treatment of porcine coronary microthromboembolism.

BACKGROUND: Coronary microthromboembolism after acute myocardial infarction (AMI) requires urgent and effective treatment. Early and effective recovery of coronary microcirculation perfusion for the management of AMI would be crucial for better prognosis. Ultrasound assisted thrombolysis in the in-vitro experiments have great potential for the elimination of acute coronary microthromboembolism, especially with stable cavitation using low-intensity focused ultrasound (LIFU) and dodecafluoropentane-loaded acoustic phase-change nanoparticles (DDFP@NPs). Therefore, our study sought to perform animal experiments using this novel treatment method in a porcine model with acute coronary microthromboembolism for further investigation of potential therapeutic values. METHODS: Porcine model with acute coronary thromboembolism was established using percutaneous coronary intervention and autologous thrombus injection. For ultrasound assisted thrombolysis, DDFP@NPs were prepared by rotary evaporation and sonication process, and LIFU was optimized. Echocardiography and TTC staining were performed for the evaluation of porcine model establishment and treatment effect. RESULTS: The treatment using LIFU guided DDFP@NPs had almost completely recanalized culprit coronary branch after treatment procedure, and smaller infarcted size (5.4 ± 1.0%), better LVEF (52.5 ± 1.8%) and better coronary microcirculation after 28 days of treatment, which outperformed treatments using LIFU+SonoVue microbubbles (infarcted size: 26.4 ± 3.5% and LVEF: 37.2 ± 3.1%) and LIFU only (infarcted size: 32.2 ± 3.1% and LVEF: 32.2 ± 0.4%) (all P < 0.05), while the treatment effect were similar to treatment using intravenous tissue-plasminogen activator (infarcted size: 4.9 ± 0.9% and LVEF: 53.1 ± 1.1%) (all P > 0.05). CONCLUSIONS: Our study has innovatively established a treatment method using DDFP@NPs combined with LIFU irradiation for coronary thrombolysis and verified its treatment effect with high-efficient thrombolysis in the in-vivo experiments, which can be considered as powerful experimental evident of the novel method for potential clinical use of acute coronary thrombolysis. Multidimensional experimental investigations and cautious verification may need before the method could be used as treatment before preliminary clinical trials.

Gut Microbiota Dysbiosis Induced by a High-Fat Diet Increases Susceptibility to Atrial Fibrillation.

BACKGROUND: Obesity is a significant risk factor for atrial fibrillation (AF), and the gut microbiota is closely related to obesity-induced diseases. However, whether the gut microbiota is involved in regulating obesity-induced AF has not been studied. This study investigated whether gut microbiota dysbiosis affects obesity-related AF. METHODS: Fecal microbes derived from normal diet (ND)-fed and high-fat diet (HD)-fed mice were transplanted into those fed normally. Morphologic, biochemical, functional, histologic, electrophysiological studies, molecular analysis, 16S rRNA gene amplicon sequencing, and RNA-sequencing were performed. RESULTS: Transplantation of the HD gut microbes in ND-maintained (THD) mice led to a significant increase in the susceptibility to AF. Gut microbiota analysis showed a significant increase in Desulfovibrionaceae, which generated metabolic endotoxemia in THD mice. Transplantation with HD microbes also resulted in significantly increased levels of circulating lipopolysaccharide (LPS), significant disruption in the histologic architecture of the intestinal tissue, and significantly increased proinflammatory cytokines in the left atrium, indicating that atrial inflammation likely contributed to AF susceptibility. RNA-sequencing showed that the THD group had enhanced activation of ferroptosis and TLR4/NF-κB/NLRP3 inflammasome signalling pathway. Inhibiting the ferroptosis or NLRP3 inflammasome signalling pathway significantly improved atrial fibrosis and reduced susceptibility to obesity-related gut dysbiosis-induced AF. CONCLUSIONS: This study provides evidence showing an original causal role of gut microbiota dysbiosis in the pathogenesis of obesity-related AF, which showed elevated LPS and dysregulation of atrial pathologic remodelling by activating ferroptosis and the TLR4/NF-κB/NLRP3 inflammasome signalling pathway.

Nomograms based on lactate dehydrogenase to albumin ratio for predicting survival in colorectal cancer.

Purpose: We aimed to determine if lactate dehydrogenase to albumin ratio (LAR) might play a prognostic role for patients with operable colorectal cancer (CRC). Patients and Methods: 1334 operable CRC patients in Wuhan Union Hospital Between July 2013 and September 2017 were enrolled in this study and were randomly appointed them into training (n=954) and validation (n=380) sets. The relationship between LAR and overall survival (OS) and disease-free survival (DFS) were determined by restricted cubic splines (RCS) with Cox regression models. LAR was then divided into three categories based on the RCS and compared to the well-known TNM stage system. Finally, survival nomograms were developed by compounding the LAR and other clinical factors. Results: Baseline LAR values and the all-cause mortality were U shaped, which slowly decreased until around 4.50 and then started to increase rapidly when the LAR ranged from 4.50-6.68 and then became flat thereafter (P for non-linearity <0.001). LAR was superior to TNM stage for OS as well as DFS and LAR plus TNM stage could add more net benefit than clinical model alone. Moreover, the survival nomograms based on LAR achieved great predictive ability for OS and DFS in operable CRC patients. Conclusions: LAR could be served as a reliable prognostic factor for OS as well as DFS, with more accurate prognostic prediction than current TNM stage for patients with operable CRC.

Low-intensity pulsed ultrasound promotes cell viability and inhibits apoptosis of H9C2 cardiomyocytes in 3D bioprinting scaffolds via PI3K-Akt and ERK1/2 pathways.

The aim of this study was to investigate whether low-intensity pulsed ultrasound (LIPUS) promotes myocardial cell viability in three-dimensional (3D) cell-laden gelatin methacryloyl (GelMA) scaffolds. Cardiomyoblasts (H9C2s) were mixed in 6% (w/v) GelMA bio-inks and printed using an extrusion-based 3D bioprinter. These scaffolds were exposed to LIPUS with different parameters or sham-irradiated to optimize the LIPUS treatment. The viability of H9C2s was measured using Cell Counting Kit-8 (CCK8), cell cycle, and live and dead cell double-staining assays. Western blot analysis was performed to determine the protein expression levels. We successfully fabricated 3D bio-printed cell-laden GelMA scaffolds. CCK8 and live and dead cell double-staining assays indicated that the optimal conditions for LIPUS were a frequency of 0.5 MHz and an exposure time of 10 min. Cell cycle analysis showed that LIPUS promoted the entry of cells into the S and G2/M phases from the G0/G1 phase. Western blot analysis revealed that LIPUS promoted the phosphorylation and activation of ERK1/2 and PI3K-Akt. The ERK1/2 inhibitor (U0126) and PI3K inhibitor (LY294002) significantly reduced LIPUS-induced phosphorylation of ERK1/2 and PI3K-Akt, respectively, which in turn reduced the LIPUS-induced viability of H9C2s in 3D bio-printed cell-laden GelMA scaffolds. A frequency of 0.5 MHz and exposure time of 10 min for LIPUS exposure can be adapted to achieve optimized culture effects on myocardial cells in 3D bio-printed cell-laden GelMA scaffolds via the ERK1/2 and PI3K-Akt signaling pathways.

Prognostic value of myocardial contrast echocardiography in acute anterior wall ST-segment elevation myocardial infarction with successful epicardial recanalization.

Although myocardial contrast echocardiography (MCE) can evaluate microvascular perfusion abnormalities, its prognostic value is uncertain in acute anterior wall ST-Segment elevation myocardial infarction (STEMI) with successful epicardial recanalization. Therefore, the study aims to investigate the prognostic role of qualitative and quantitative MCE in acute anterior wall STEMI with successful epicardial recanalization. 153 STEMI patients were assessed by MCE within 7 days after successful epicardial recanalization. Qualitative perfusion parameters (microvascular perfusion score index, MPSI) and quantitative perfusion parameters (A, ß, and Aß) were acquired using a 17-segment model. And corrected A and Aß were calculated. Patients were all followed for major adverse cardiovascular events (MACEs). During median follow-up of 27 (4) months, 39 (25.49%) patients experienced MACEs, while 114 (74.51%) were free from MACEs. Patients with MACEs had higher MPSI (1.65 ± 0.13 vs. No-MACEs 1.35 ± 0.20, P < 0.001), lower ß (1.09 ± 0.19 s-1 vs. No-MACEs 1.34 ± 0.30 s-1, P < 0.001), corrected A (0.17 ± 0.03 dB vs. No-MACEs 0.19 ± 0.04 dB, P = 0.039) and lower corrected Aß (0.19 ± 0.06 dB/s vs. No-MACEs 0.25 ± 0.08 dB/s, P < 0.001). MPSI of 1.44 provided an area under the curve (AUC) of 0.872, while ß of 1.18 s-1 and corrected Aß of 0.22 dB/s provided AUCs of 0.759 and 0.724, respectively. The combination of MPSI, ß and corrected Aß provided an increased AUC of 0.964 (all P < 0.05). Time-dependent ROC analysis showed that the AUCs of the MPSI, ß, corrected Aß and the combination at 1, 1.5 and 2 years indicated a strong predictive power for MACEs (AUC = 0.900/0.894/0.881 for MPSI, 0.648/0.704/0.732 for ß, 0.674/0.686/0.722 for corrected Aß, and 0.947/0.962/0.967 for the combination, respectively). Patients with MPSI < 1.44, ß > 1.18 s-1, or corrected Aß > 0.22 dB/s had lower event rate (all Log Rank P ≤ 0.001). MPSI, ß, corrected Aß, GLS and WBC were independent predictors of MACEs with adjusted hazard ratio of 34.41 (8.18-144.87), P < 0.001 for MPSI; 39.29 (27.46-65.44), P < 0.001 for ß; 8.93 (1.46-54.55), P = 0.018 for corrected Aß; 10.88 (2.83-41.86), P = 0.001 for GLS; and 1.43 (1.16-1.75), P = 0.001 for WBC. Qualitative and quantitative MCE can accurately predict MACEs in acute anterior wall STEMI with successful epicardial recanalization, and their combined predictive value is higher.

RASSF8-mediated transport of Echinoid via the exocyst promotes Drosophila wing elongation and epithelial ordering.

Cell-cell junctions are dynamic structures that maintain cell cohesion and shape in epithelial tissues. During development, junctions undergo extensive rearrangements to drive the epithelial remodelling required for morphogenesis. This is particularly evident during axis elongation, where neighbour exchanges, cell-cell rearrangements and oriented cell divisions lead to large-scale alterations in tissue shape. Polarised vesicle trafficking of junctional components by the exocyst complex has been proposed to promote junctional rearrangements during epithelial remodelling, but the receptors that allow exocyst docking to the target membranes remain poorly understood. Here, we show that the adherens junction component Ras Association domain family 8 (RASSF8) is required for the epithelial re-ordering that occurs during Drosophila pupal wing proximo-distal elongation. We identify the exocyst component Sec15 as a RASSF8 interactor. Loss of RASSF8 elicits cytoplasmic accumulation of Sec15 and Rab11-containing vesicles. These vesicles also contain the nectin-like homophilic adhesion molecule Echinoid, the depletion of which phenocopies the wing elongation and epithelial packing defects observed in RASSF8 mutants. Thus, our results suggest that RASSF8 promotes exocyst-dependent docking of Echinoid-containing vesicles during morphogenesis.

[Effect evaluation of bedside ultrasound monitoring of left ventricular functional parameters combined with clinical indicators on veno-arterial extracorporeal membrane oxygenation].

OBJECTIVE: To explore the monitoring value of left ventricular functional parameters obtained by bedside ultrasound combined with clinically relevant indicators in patients with veno-arterial extracorporeal membrane oxygenation (VA-ECMO). METHODS: A retrospective study was conducted. A total of 24 patients receiving VA-ECMO adjuvant support in Renmin Hospital of Wuhan University from June 2018 to January 2020 were selected. The bedside ultrasound was performed on the first day of ECMO support, the day before weaning, the clinical indicators before weaning were obtained. The differences in clinical indicators and the left ventricular functional parameters between the two groups of whether weaning successfully were compared; univariate Logistic regression analysis was used to screen out the related factors affecting weaning. RESULTS: Sixteen patients were successful weaned and 8 patients failed. Compared with the weaning failure group, patients in the weaning success group required less continuous renal replacement therapy (CRRT, cases: 4 vs. 6, P < 0.05), mean arterial pressure (MAP) before weaning was higher [mmHg (1 mmHg = 0.133 kPa): 84.64±9.55 vs. 62.30±8.79, P < 0.05], and the pulse oxygen saturation (SpO2) was also higher (0.966±0.670 vs. 0.866±0.061, P < 0.05), while vasoactive-inotropic score (VIS), serum creatinine (SCr) and serum lactic acid (Lac) were lower [VIS score: 7.27±1.42 vs. 16.93±8.52, SCr (µmol/L): 123.60±83.64 vs. 213.10±117.39, Lac (mmol/L): 1.94±0.91 vs. 5.62±5.48, all P < 0.05]. Univariate Logistic regression analysis showed that the MAP, VIS, SCr, Lac, SpO2 before weaning were the related factors affecting weaning [odds ratio (OR) were 0.306, -0.740, -0.011, -0.632, -4.069; 95% confidence interval (95%CI) were 1.065-1.732, 0.235-0.899, 0.979-0.999, 0.285-0.992 and 0.001-0.208; P values were 0.014, 0.022, 0.038, 0.047, 0.002]. In the weaning success group, left ventricular ejection fraction (LVEF), velocity of mitralannulus in systolic (LatSa), maximum flow velocity of aortic valve (AV-Vmax), velocity-time integral (VTI), left ventricular global longitudinal strain (LVGLS), left ventricular global longitudinal strain rate (LVGLSr) were all increased on the day before ECMO weaning compared with the first day of ECMO support [LVEF: 0.40±0.05 vs. 0.28±0.07, LatSa (cm/s): 6.81±0.91 vs. 4.62±1.02, AV-Vmax (cm/s): 104.81±33.98 vs. 64.44±16.85, VTI (cm): 14.56±3.11 vs. 7.96±1.98, LVGLS: (-8.95±2.59)% vs. (-5.26±1.28)%, LVGLSr (1/s): -0.48±0.11 vs. -0.29±0.09], whereas the ECMO flow was significantly reduced (L/min: 1.46±0.47 vs. 2.64±0.31), the differences were statistically significant (all P < 0.05). There was no significant difference in left ventricular functional parameters between the first day of ECMO support and the day before ECMO weaning in the weaning failure group. Compared with the weaning failure group, the weaning success group had higher LVEF, LatSa, AV-Vmax, VTI, LVGLS, LVGLSr on the day before ECMO weaning [LVEF: 0.40±0.05 vs. 0.26±0.07, LatSa (cm/s): 6.81±0.91 vs. 4.31±1.03, AV-Vmax (cm/s): 104.81±33.98 vs. 67.67±18.46, VTI (cm): 14.56±3.11 vs. 7.75±2.77, LVGLS: (-8.95±2.59)% vs. (-4.81±1.81)%, LVGLSr (1/s): -0.48±0.11 vs. -0.30±0.10, all P < 0.05] and lower ECMO flow (L/min: 1.46±0.47 vs. 2.20±0.62, P < 0.05). CONCLUSIONS: Bedside echocardiographic left ventricular function parameters (LVEF, LatSa, AV-Vmax, VTI, LVGLS, LVGLSr) combined with clinical indicators (MAP, VIS, SCr, Lac, SpO2) were helpful to evaluate the therapeutic effect of patients receiving VA-ECMO support and can provide important guiding value in the selection of VA-ECMO weaning timing and the judgment of prognosis.

Ultrasound-targeted microbubble destruction-mediated Ang1 gene transfection improves left ventricular structural and sympathetic nerve remodeling in canines with myocardial infarction.

BACKGROUND: The present study aimed to determine whether ultrasound-targeted microbubble destruction (UTMD)-mediated angiopoietin 1 (Ang1) gene transfection can improve angiogenesis and potentially reverse left ventricular (LV) structural and sympathetic nerve remodeling in canines with myocardial infarction (MI). METHODS: Thirty dogs were randomly divided into groups (n=10/group) as follows: the MI group (MI dogs without UTMD treatment), the UTMD group (MI dogs with UTMD-mediated negative control plasmid treatment), and the UTMD-Ang1 group (MI dogs with UTMD-mediated Ang1 plasmid treatment). LV dimensions, systolic function, and synchrony were used to reflect the structural remodeling. The density of tyrosine hydroxylase (TH)- and growth-associated protein 43 (GAP43)-positive nerve fibers were calculated to assess the sympathetic nerve remodeling. RESULTS: One month after treatment, the UTMD-Ang1 group showed lower LV end-diastolic dimension (LVEDD: 31.2±2.3 mm) and higher LV ejection fraction (LVEF: 44.6%±4.3%) than the MI group (LVEDD: 34.5±2.2 mm, t=2.282, P=0.014; LVEF: 37.3%±3.1%, t=3.718, P=0.003) and the UTMD group (LVEDD: 34.1±2.8 mm, t=2.264, P=0.040; LVEF: 39.3%±4.5%, t=2.408, P=0.030). LV synchrony was higher in the UTMD-Ang1 group compared with the MI group by 2-dimensional speckle-tracking echocardiography. Angiogenic density was higher in the UTMD group than the MI group but was highest in the UTMD-Ang1 group according to immunohistochemistry of CD31 and α-smooth muscle actin staining. The density of TH- and GAP43-positive nerve fibers were decreased in the UTMD-Ang1 group (TH: 1,928.2±376.6 µm2/mm2; GAP43: 2,090.8±329.2 µm2/mm2) compared with the MI group (TH: 2916.5±558.4 µm2/mm2, t=4.069, P=0.001; GAP43: 3,275.4±548.6 µm2/mm2, t=5.153, P=0.000) and the UTMD group (TH: 2,552.7±408.1 µm2/mm2, t=3.181, P=0.007; GAP43: 2,630.5±419.3 µm2/mm2, t=2.863, P=0.013). The relative Ang1 and sarcoplasmic reticulum Ca2+-ATPase 2a protein levels were significantly higher in the UTMD-Ang1 group than the UTMD and MI groups by Western blot, while the phospholamban levels exhibited the opposite trend. Plasma norepinephrine and N-terminal pro-B-type-natriuretic peptide were significantly reduced in the UTMD-Ang1 group from day 1 to 1 month after MI. CONCLUSIONS: UTMD-mediated Ang1 transfection can promote angiogenesis, reverse LV structural and sympathetic nerve remodeling, and improve LV synchrony after MI.

Transthoracic ultrasound-guided percutaneous intramyocardial injection combined with ultrasound-targeted microbubble destruction-mediated angiogenin 1 gene therapy in canine myocardial infarction model.

BACKGROUND: Intravenous (IV) ultrasound-targeted microbubble destruction (UTMD) has made distinct but limited progress in gene transfected therapy. Intramyocardial (IM) injection also has some effect. In this study, IM injection could be performed under the guidance of transthoracic ultrasound without thoracotomy. We aimed to evaluate the effect of combination transthoracic ultrasound-guided percutaneous IM injection and UTMD for mediating the angiogenin 1 (Ang1) gene therapy in myocardial infarction (MI) canines. METHODS: Forty-two canines were divided into four groups: IM-UTMD group (intramyocardial injection of the negative control plasmid with UTMD as the sham group); IM-Ang1 group (intramyocardial injection of the Ang1 plasmid without UTMD); IM-Ang1-UTMD group (intramyocardial injection of the Ang1 plasmid with UTMD); and IV-Ang1-UTMD group (intravenous injection of the Ang1 plasmid with UTMD). The FITC green fluorescence and Ang1 protein in myocardial tissue were used for the distribution of Ang1 gene. Left ventricular dimension and systolic function were observed by echocardiography. The Masson's and Sirius Red's staining were used for evaluating the collagen fiber. The immunohistochemistry for CD31 and alpha-smooth muscle actin (α-SMA) were as the indicators of microvasculature. Myocardial contrast echocardiography was used to reflect the microvascular perfusion. RESULTS: More FITC-labeled plasmid was observed in the three IM injection groups than in the IV-Ang1-UTMD group, and the Ang1 protein expression was higher in the IM-Ang1-UTMD group. One month later, no significant differences in survival rate and complications were observed among all four groups. Although there were no differences in the left ventricular end-diastolic diameter among the 4 groups, the left ventricular end-systolic diameter was lower in the IM-Ang1-UTMD group than in the other groups. Then, the left ventricular ejection fraction was increased in the IM-Ang1-UTMD group, with lower collagen fiber percentage, higher blood vessel density and myocardial reperfusion intensity than those in the other groups (P<0.05). CONCLUSIONS: Transthoracic ultrasound-guided percutaneous IM injection combined with UTMD is a safe and effective method for mediating Ang1 plasmid therapy in MI canines.

Carotid baroreceptor stimulation improves cardiac performance and reverses ventricular remodelling in canines with pacing-induced heart failure.

AIMS: Carotid baroreceptor stimulation (CBS) has potential protective effects on chronic heart failure (CHF). The aim of our study was to investigate the effects of CBS on more detailed aspects of ventricular remodelling and the underlying mechanisms in a CHF canine model. MAIN METHODS: Twenty-four beagles were randomised into Con (n = 8), CHF (n = 8), and CHF-CBS (n = 8) groups. The CHF and CHF-CBS groups underwent 6 weeks of rapid ventricular pacing (RVP) at 250 beats per minute to establish a CHF model. Concomitant CBS was delivered together with RVP in the CHF-CBS group. KEY FINDINGS: RVP for 6 weeks caused typical heart failure in the CHF group. CBS significantly reversed the decrease in the high-frequency heart rate variability component and increase in low-frequency/high-frequency ratio induced by RVP. CBS significantly reduced cardiac dilation, improved left ventricle ejection fraction, and inhibited the increase in natriuretic peptide mRNA expression of LV tissue. CBS alleviated collagen volume fraction and reduced protein expression of transforming growth factor ß1, matrix metallopeptidase 2, and matrix metallopeptidase 9, as well as decreased the percentage of TUNEL-positive nuclei and protein expression of Caspase-3 in LV tissue. The intracellular PKA signalling pathway and cardiac inflammation of LV tissue were upregulated in the CHF group, and markedly inhibited by CBS. SIGNIFICANCE: Our study found that CBS improved cardiac performance and reversed ventricular remodelling in CHF canines by rebalancing the autonomic nervous system; the suppression of the intracellular PKA signalling pathway and cardiac inflammation might underly the mechanisms.

ASPP proteins discriminate between PP1 catalytic subunits through their SH3 domain and the PP1 C-tail.

Serine/threonine phosphatases such as PP1 lack substrate specificity and associate with a large array of targeting subunits to achieve the requisite selectivity. The tumour suppressor ASPP (apoptosis-stimulating protein of p53) proteins associate with PP1 catalytic subunits and are implicated in multiple functions from transcriptional regulation to cell junction remodelling. Here we show that Drosophila ASPP is part of a multiprotein PP1 complex and that PP1 association is necessary for several in vivo functions of Drosophila ASPP. We solve the crystal structure of the human ASPP2/PP1 complex and show that ASPP2 recruits PP1 using both its canonical RVxF motif, which binds the PP1 catalytic domain, and its SH3 domain, which engages the PP1 C-terminal tail. The ASPP2 SH3 domain can discriminate between PP1 isoforms using an acidic specificity pocket in the n-Src domain, providing an exquisite mechanism where multiple motifs are used combinatorially to tune binding affinity to PP1.

The predictive value of intra-left atrial mechanical delay for 1-year recurrence of atrial fibrillation after catheter ablation: A clinical follow-up study using dual Doppler echocardiography.

PURPOSE: The availability of dual Doppler echocardiography (DDE), which facilitates the simultaneous recording of Doppler waveforms at two different sites, has enhanced ability to assess single-beat atrial mechanical delay. We sought to investigate the predictive value of intra-left atrial mechanical delay for atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA) with DDE. METHODS: Eighty-six patients with paroxysmal AF scheduled to undergo RFCA were prospectively enrolled. Intra-atrial and interatrial mechanical delays were evaluated by DDE and traditional tissue Doppler imaging (tTDI), respectively. The time of whole analysis process with each method was recorded. After RFCA, patients were followed for 1 year. RESULTS: Thirty (34.88%) patients had AF recurrence, and 56 (65.12%) patients maintained sinus rhythm. Cut-off values of 39.38 ms for intra-left atrial mechanical delay obtained by DDE and 32.70 ms by tTDI predicted AF recurrence. Areas under curves were comparable in receiver operator characteristic analysis (P > .05). The whole analysis time of DDE was less than tTDI. Parameters obtained by DDE had better reproducibility. CONCLUSION: Intra-left atrial mechanical delay best predicted 1-year AF recurrence after RFCA. Compared with tTDI, DDE can noninvasively assess single-beat atrial mechanical delay with high predictive power, less analysis time, and better reproducibility.