CAV1 Protein Encapsulated in Mouse BMSC-Derived Extracellular Vesicles Alleviates Myocardial Fibrosis Following Myocardial Infarction by Blocking the TGF-ß1/SMAD2/c-JUN Axis.

Extracellular vesicles (EVs) derived from mouse bone marrow mesenchymal stem cells (mBMSCs) convey the CAV1 protein, influencing the TGF-ß1/SMAD2/c-JUN pathway and thus the molecular mechanisms underlying myocardial fibrosis (MF) post-myocardial infarction (MI). Through various experimental methods, including transmission electron microscopy, Nanosight analysis, Western blot, ELISA, and qRT-PCR, we isolated, purified, and identified EVs originating from mBMSCs. Bioinformatics and experimental findings show a reduced expression of CAV1 in myocardial fibrosis tissue. Furthermore, our findings suggest that mBMSC-EVs can deliver CAV1 to cardiac fibroblasts (CFs) and that silencing CAV1 in mBMSC-EVs promotes CF fibrosis. In vivo studies further corroborated these findings. In conclusion, mBMSC-EVs mitigate myocardial fibrosis in MI mice by delivering the CAV1 protein, inhibiting the TGF-ß1/SMAD2/c-JUN pathway. Molecular mechanism of mBMSC-EVs-CAV1-mediated TGF-ß1/SMAD2/c-JUN axis in inhibiting cardiac fibroblast differentiation to improve MF after MI. mBMSC-EVs deliver CAV1 protein to CFs where the protein expression of CAV1 is upregulated upon hypoxia conditions. The TGF-ß1/SMAD2 signaling pathway downstream of CAV1 is consequently inactivated, the transcription of c-JUN is inhibited, and transcription of SMAD2/c-JUN transcription complex target genes α-SMA and Collagen I is reduced. By this mechanism, CF fibrosis and apoptosis are suppressed in vitro and MF is ameliorated in MI mice.

Inclusion of interleukin-6 improved the performance of postoperative acute lung injury prediction for patients undergoing surgery for thoracic aortic disease.

Background: We studied acute lung injury (ALI) in thoracic aortic disease (TAD) patients and investigated the predictive effect of interleukin-6 (IL-6) in acute lung injury after thoracic aortic disease. Methods: Data on 188 TAD patients, who underwent surgery between January 2016 to December 2021 at our hospital, were enrolled in. We analyzed acute lung injury using two patient groups. Patients with No-ALI were 65 and those with ALI were 123. Univariate logistic, LASSO binary logistic regression model and multivariable logistic regression analysis were performed for acute lung injury. Results: Preoperative IL-6 level was lower (15.80[3.10,43.30] vs. 47.70[21.40,91.60] pg/ml, p < 0.001) in No-ALI group than in ALI group. The cut-off points, determined by the ROC curve, were preoperative IL-6 > 18 pg/ml (area under the curve: AUC = 0.727). Univariate logistic regression analysis showed 19 features for TAD appeared to be early postoperative risk factors of acute lung injury. Using LASSO binary logistic regression, 19 features were reduced to 9 potential predictors (i.e., Scrpost + PLTpost + CPB > 182 min + D-dimerpost + D-dimerpre + Hypertension + Age > 58 years + IL6 > 18 pg/ml + IL6). Multivariable logistic regression analysis showed that Postoperative creatinine, CPB > 182 min and IL-6 > 18 pg/ml were early postoperative risk factors for ALI after TAD, and the odds ratios (ORs) of postoperative creatinine, CPB > 182 min and IL-6 > 18 pg/ml were 1.006 (1.002-1.01), 4.717 (1.306-19.294) and 2.96 (1.184-7.497), respectively. When postoperative creatinine, CPB > 182 min and IL-6 > 18 pg/ml (AUC = 0.819), the 95% confidence interval [CI] was 0.741 to 0.898. Correction curves were nearly diagonal, suggesting that the nomogram fit well. The DCA curve was then drawn to demonstrate clinical applicability. The DCA curve showed that the threshold probability of a patient is in the range of 30% to 90%. Conclusions: The inclusion of interleukin-6 demonstrated good performance in predicting ALI after TAD surgery.

Computational modeling of hemodynamics and risk of thrombosis in the left atrial appendage using patient-specific blood viscosity and boundary conditions at the mitral valve.

Hemodynamics play a vital role for the risk of thrombosis in the left atrial appendage (LAA) and left atrium (LA) for patients with atrial fibrillation. Accurate prediction of hemodynamics in the LA can provide important guidance for assessing the risk of thrombosis in the LAA. Patient specificity is a crucial factor in representing the true hemodynamic fields. In this study, we investigated the effects of blood rheology (as a function of hematocrit and shear rate), as well as patient-specific mitral valve (MV) boundary conditions (MV area and velocity profiles measured by ultrasound) on the hemodynamics and thrombosis potential of the LAA. Four scenarios were setup with different degrees of patient specificity. Though using a constant blood viscosity can classify the thrombus and non-thrombus patients for all the hemodynamic indicators, the risk of thrombosis was underestimated for all patients compared with patient-specific viscosities. The results with least patient specificities showed that patients prone to thrombosis predicted by three hemodynamic indicators were inconsistent with clinical observations. Moreover, though patients had the same MV inlet flow rate, different MV models lead to different trends in the risk of thrombosis in different patients. We also found that endothelial cell activation potential and relative residence time can effectively distinguish thrombus and non-thrombus patients for all the scenarios, relatively insensitive to patient specificities. Overall, the findings of this study provide useful insights on patients-specific hemodynamic simulations of the LA.

Surgical treatment strategies for patients with type A aortic dissection involving arch anomalies.

Objective: The aim of the study was to investigate surgical modalities and outcomes in patients with type A aortic dissection involving arch anomalies. Method: Patients with type A aortic dissection who underwent surgical treatment at our center between January 2017 and 31 December 2020 were selected for this retrospective analysis. Data including computed tomography (CT), surgical records, and cardiopulmonary bypass records were analyzed. Perioperatively survived patients were followed up, and long-term mortality and aortic re-interventions were recorded. Result: A total of 81 patients with arch anomalies were included, 35 with "bovine" anomalies, 23 with an aberrant right subclavian artery, 22 with an isolated left vertebral artery, and one with a right-sided arch + aberrant left subclavian artery. The strategies of arch management and cannulation differed according to the anatomic variation of the aortic arch. In total, seven patients (9%) died after surgery. Patients with "bovine" anomalies had a higher perioperative mortality rate (14%) and incidence of neurological complications (16%). Overall, four patients died during the follow-up period, with a 6-year survival rate of 94.6% (70/74). A total of four patients underwent aortic re-intervention during the follow-up period; before the re-intervention, three received the en bloc technique (13.6% 3/22) and one received hybrid therapy (11.1% 1/9). Conclusion: With complete preservation and reconstruction of the supra-arch vessels, patients with type A aortic dissection combining arch anomalies can achieve a favorable perioperative prognostic outcome. Patients who received the en bloc technique are more likely to require aortic re-intervention than patients who underwent total arch replacement with a four-branched graft vessel. Cannulation strategies should be tailored according to the variation of anatomy, but routine cannulation with the right axillary artery can still be performed in most patients with arch anomalies, even for patients with an aberrant right subclavian artery.

Long-term outcome prediction for chronic thromboembolic pulmonary hypertension after pulmonary endarterectomy.

BACKGROUND: The definitive treatment for chronic thromboembolic pulmonary hypertension (CTEPH) is pulmonary endarterectomy (PEA), which has good long-term outcomes. However, after surgery, a quarter of the patients still have residual pulmonary hypertension (RPH). In pulmonary hemodynamics, there are no unified criteria for RPH, even though the level may affect long-term survival. METHODS: Between March 1997 and December 2021, 253 CTEPH patients were treated at our center with PEA. Patients were evaluated retrospectively and classified into early (1997-2014) and late (2015-2021) groups. The clinical characteristics and perioperative outcomes of the two groups were compared, and risk factor analysis for RPH and long-term survival for all cases was performed. RESULTS: There was no statistically significant difference in demographics between the two groups. However, the Early Group had a significantly higher rate of perioperative death (9.8% vs. 1.2%, p = .001), RPH (48.8% vs. 14.0%, p < .001), and reperfusion pulmonary edema (18.3% vs. 2.9%, p < .001). The median follow-up time was 66.0 months, and overall survival rates at 5, 10, 15, and 18 years after PEA were 91.2%, 83.9%, 64.5%, and 46.0%, respectively. Age and postoperative systolic pulmonary artery pressure (sPAP) were independently related to long-term outcomes in the multivariate Cox analyses. Patients with postoperative sPAP less than 46 mm Hg had a higher chance of survival. CONCLUSIONS: PEA improved CTEPH hemodynamics immediately and had a positive effect on long-term survival. Patients with postoperative sPAP ≥ 46 mm Hg indicate clinically significant RPH and have a lower long-term survival rate.

Estimation of Mycophenolic Acid Exposure in Heart Transplant Recipients by Population Pharmacokinetic and Limited Sampling Strategies.

Purpose: The aim of this study is i) to establish a strategy to estimate the area under the curve of the dosing interval (AUC0-12h) of mycophenolic acid (MPA) in the heart transplant recipients and ii) to find the covariates that significantly affect the pharmacokinetics of MPA exposure. Methods: This single-center, prospective, open-label, observational study was conducted in 91 adult heart transplant recipients orally taking mycophenolate mofetil dispersible tablets. Samples collected intensively and sparsely were analyzed by the enzyme-multiplied immunoassay technique, and all the data were used in PPK modeling. Potential covariates were tested stepwise. The goodness-of-fit plots, the normalized prediction distribution error, and prediction-corrected visual predictive check were used for model evaluation. Optimal sampling times by ED-optimal strategy and multilinear regression (MLR) were analyzed based on the simulated data by the final PPK model. Moreover, using intensive data from 14 patients, the accuracy of AUC0-12h estimation was evaluated by Passing-Bablok regression analysis and Bland-Alman plots for both the PPK model and MLR equation. Results: A two-compartment model with first-order absorption and elimination with a lag time was chosen as the structure model. Co-medication of proton pump inhibitors (PPIs), estimated glomerular filtration rate (eGFR), and albumin (ALB) were found to significantly affect bioavailability (F), clearance of central compartment (CL/F), and the distribution volume of the central compartment (V2/F), respectively. Co-medication of PPIs decreased F by 27.6%. When eGFR decreased by 30 ml/min/1.73 m2, CL/F decreased by 23.7%. However, the impact of ALB on V2/F was limited to MPA exposure. The final model showed an adequate fitness of the data. The optimal sampling design was pre-dose and 1 and 4 h post-dose for pharmacokinetic estimation. The best-fit linear equation was finally established as follows: AUC0-12h = 3.539 × C0 + 0.288 × C0.5 + 1.349 × C1 + 6.773 × C4.5. Conclusion: A PPK model was established with three covariates in heart transplant patients. Co-medication of PPIs and eGFR had a remarkable impact on AUC0-12h of MPA. A linear equation was also concluded with four time points as an alternative way to estimate AUC0-12h for MPA.

The recent 10-year landscape of aortic dissection research: a bibliometric analysis.

BACKGROUND: We aimed to comprehensively analyze all the literature related to aortic dissection (AD) in the past decade using Web Scrapping technology from PubMed, revealing the research dynamics in this field. METHODS: Data were retrieved and downloaded from PubMed with search strategy as "(aortic dissection [Title/Abstract]) AND (2010[EDAT]: 2020[EDAT])". Information on the PMID, journal name, title, number of citations, publication year, authors, affiliations, abstract, study type, and keywords of the research was recorded. RESULTS: A total of 7,470 publications were identified. Most of the articles were published in J Thorac Cardiovasc Surg; Japan was the country with the largest publications number; the USA was far ahead of other countries regarding the highly cited studies; Yale University and Baylor College of Medicine took the first place for publishing most of the highly cited articles; the most frequently cited article is the 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases; most of the clinical trials were published on J Vasc Surg; John A. Elefteriades ranked first by cumulative publication numbers; Christoph A. Nienaber took the lead by both cumulative citations and impact factors; Dianna M. Milewicz was the only female researcher on all the three ranking lists; the most common keywords in aortic dissection were Treatment Outcome and Retrospective Studies. CONCLUSIONS: This study provides interesting insights into the AD scientific landscape in recent 10 years and generates some objective evidence for comprehensive understanding and evaluation of this field. This investigation may ultimately inform managers, researchers and policymakers.

Surgical treatment of pulmonary artery sarcoma: a report of 17 cases.

Pulmonary artery sarcoma (PAS) is a rare and devastating disease. The diagnosis is often delayed, and optimal treatment remains unclear. The aim of this study is to report our experience in the surgical management of this disease. Between 2000 and 2018, 17 patients underwent operations for PAS at our center. The medical records were retrospectively reviewed to evaluate the clinical characteristics, operative findings, the postoperative outcomes, and the long-term results. The mean age at operation was 46.0 ± 12.4 years (range, 26-79 years), and eight (47.1%) patients were male. Six patients underwent tumor resection alone, whereas the other 11 patients received pulmonary endarterectomy (PEA). There were two perioperative deaths. Follow-up was completed for all patients with a mean duration of 23.5 ± 17.6 months (1-52 months). For all 17 patients, the median postoperative survival was 36 months, and estimated cumulative survival rates at 1, 2, 3, and 4 years were 60.0%, 51.4%, 42.9%, and 21.4%, respectively. The mean survival was 37.0 months after PEA and 14.6 months after tumor resection only (p = 0.046). Patients who had no pulmonary hypertension (PH) postoperatively were associated with improved median survival (48 vs. 5 months, p = 0.023). In conclusion, PAS is often mistaken for chronic pulmonary thromboembolism. The prognosis of this very infrequent disease remains poor. Early detection is essential for prompt and best surgical approach, superior to tumor resection alone, and PEA surgery with PH relieved can provide better chance of survival.

A novel mutation of walK confers vancomycin-intermediate resistance in methicillin-susceptible Staphylococcus aureus.

With the treatment failure by vancomycin and poor clinical outcomes, the emergence and spread of vancomycin intermediate-resistant Staphylococcus aureus (VISA) has raised more concerns in recent years. While most VISA strains are isolated from methicillin-resistant S. aureus (MRSA), the mechanism underlying the generation of VISA from methicillin-susceptible S. aureus (MSSA) is still largely unknown. Here, we identified a total of 10 mutations in 9 genes through comparative genome analysis from laboratory-derived VISA strain. We verified the role of a novel mutation of WalK (I237T) and our results further indicated that the introduction of WalK (I237T) by allelic replacement can confer vancomycin resistance in MSSA with common VISA characteristics, including thickened cell walls, reduced autolysis, and attenuated virulence. Consistent with these phenotypes, real-time quantitative reverse transcription-PCR revealed the altered expression of several genes associated with cell wall metabolism and virulence control. In addition, electrophoretic mobility shift assay indicated that WalR can directly bind to the promoter regions of oatA, sle1, and mgt, fluorescence-based promoter activity and ß-galactosidase assays revealed WalK (I237T) can alter promoter activities of oatA, mgt, and sle1, thus regulating genes expression. These findings broaden our understanding of the regulatory network by WalKR system and decipher the molecular mechanisms of developmental VISA resistance in MSSA with point mutations.

A novel type I toxin-antitoxin system modulates persister cell formation in Staphylococcus aureus.

A plethora of toxin-antitoxin systems exist in bacteria and has multilateral roles in bacterial pathogenesis and virulence. Toxin-antitoxin systems have been involved in persister cell formation in Escherichia coli and Mycobacterium but have not been reported to be associated with Staphylococcus aureus persistence. Persistence is the ability of bacterial cells to tolerate unfavorable conditions and multiple stresses. There are less known and more unknown factors that either alleviate or aggravate bacterial persistence phenomenon. For the first time, we reported a new chromosomally encoded tripartite toxin-antitoxin system and its role in S. aureus persister cell formation. The toxin gene is bacteriostatic in action and counterbalanced by antitoxin RNA that could basepair with the toxin mRNA and formed a duplex. The transcriptional regulator positively regulates the toxin expression under certain stress conditions. The toxin ectopic induction increased S. aureus susceptibility to norfloxacin, ciprofloxacin, and ofloxacin. Whole-genome RNA sequencing revealed that MDR efflux pump norA is significantly down-regulated by toxin ectopic induction. The deletion of norA from S. aureus genome reduced resistance toward ciprofloxacin, norfloxacin, and ofloxacin, as well as resulted in a decrease in minimal inhibitory concentration while complementation of norA successfully restored the phenotypes. The persistence assay of the norA mutant revealed that deletion of norA increased persister cell survival in S. aureus. Altogether, we have provided insight into the first tripartite type-I TA system and revealed the role of MDR NorA in the persister cell formation of S. aureus.

Perfusion strategy and mid-term results of 58 consecutive pulmonary endarterectomy.

OBJECTIVE: The aim of this retrospective study was to review and report short-term and mid-term outcomes of pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension at our institute in the recent 2 years and to describe perfusion strategy. METHODS: A total of 58 consecutive patients with chronic thromboembolic pulmonary hypertension underwent pulmonary endarterectomy under deep hypothermia circulatory arrest with an established perfusion practice between November 2015 and December 2017. Peri-operative data and patients' outcome were retrospectively analyzed. RESULTS: Mean pulmonary artery pressure was decreased (49 (40-56) mmHg vs 27 (20-31) mmHg, p < 0.001), and pulmonary vascular resistance (724 (538-1108) vs 206 (141-284) dyn second cm-5, p < 0.001) improved significantly after surgery. In-hospital mortality was 1.7% and postoperative complication rate was 27.6%. Antipsychotic medication of olanzapine was prescribed for 36 patients (62.1%), which was independently related to total deep hypothermic circulatory arrest time, postoperative blood potassium concentration, and hematocrit. The majority of patients recovered uneventfully with good mid-term cardiac function (New York Heart Association I-II: 98.1%) and neurological outcome (Glasgow Outcome Scale-Extended Upper Good Recovery: 74.1% and Lower Good Recovery: 20.3%). Mid-term neurological outcome was associated with post-pulmonary endarterectomy antipsychotic medication. CONCLUSION: Short-term and mid-term outcome after pulmonary endarterectomy was comparable to high-volume centers. Incidence of post-pulmonary endarterectomy delirium was relatively high and associated with mid-term neurological outcome. Total deep hypothermic circulatory arrest time, postoperative blood potassium concentration, and hematocrit were independent risk factors of postoperative olanzapine medication. More efforts and further research are required to optimize the neuroprotection of perfusion practice.

Pulmonary balloon angioplasty for patients with chronic thromboembolic pulmonary hypertension accompanying with progressed pulmonary hypertension after pulmonary endarterectomy / 中国胸心血管外科临床杂志

@#Objective    To describe the effect of sequential pulmonary balloon angioplasty for patients with chronic thromboembolic pulmonary hypertension, who was accompanied with progressed pulmonary hypertension after pulmonary endarterectomy surgeries. Methods    From 2014 to December 2017, 7 patients were treated with a combination therapy of pulmonary endarterectomy and sequential pulmonary balloon angioplasty. There were 1 male and 6 females at age of 58 (43–59) years. A follow-up period of more than 1 year was accomplished. The result of right sided heart catheterization and ultrasonic cardiogram between and after the pulmonary endarterectomy or balloon angioplasty was collected. Results    Seven patients were treated with a combination of pulmonary endarterectomy and sequential pulmonary balloon angioplasty, which included 1 patient of single pulmonary balloon angioplasty and 6 patients of multiple pulmonary balloon angioplasties. The balloon dilation times was 2 (2–6), and the number of segments during each single balloon dilatation was 3–5, compared with the first clinical results before  the first balloon dilation, systolic pulmonary artery pressure [53 (47–75) mm Hg vs. 45 (40–54) mm Hg, P=0.042), mean pulmonaryartery pressure [38 (29–47) mm Hg vs. 29 (25–39) mm Hg, P=0.043], N terminal-B type natriuretic peptide [1 872 (1 598–2 898) pg/ml vs. 164 (72–334) pg/ml, P=0.018] improved significantly after the last balloon angioplasty. Heart function classification (NYHA) of all the 7 patients were recovered to Ⅰ-Ⅱclasses (P<0.05). Conclusion    Sequential pulmonary balloon angioplasty after pulmonary endarterectomy can further reduce the patient's right heart after load, improve the heart function for patients with progressed pulmonary hypertension after pulmonary endarterectomy surgeries.

Clinical presentation and surgical treatment of primary pulmonary artery sarcoma.

OBJECTIVES: Pulmonary artery sarcoma (PAS) is a rare and devastating disease. The diagnosis modality and optimal surgical strategy remain unclear. The aim of this study was to report our surgical experience in this disease. METHODS: Between 2000 and 2017, 13 patients underwent operations for PAS at our institution. Five patients underwent tumour resection alone, whereas the other 8 patients received pulmonary endarterectomy. The medical records were retrospectively reviewed to evaluate the clinical characteristics, operative findings and the postoperative outcomes. RESULTS: There were 2 perioperative deaths, both had unresolved severe pulmonary hypertension. Follow-up was completed for all patients with a mean duration of 14.3 months (1-48 months). During follow-up, 6 patients died after a mean survival time of 20.2 months (4-48 months). For the 5 patients alive at follow-up (mean duration of 7.2 months), 3 already had local recurrence. For all 13 patients, the cumulative survival rates at 1, 2 and 3 years were 56.4, 37.6 and 18.8%, respectively. The 8 patients treated with pulmonary endarterectomy seemed to have a better survival rate compared with the remaining 5 patients without endarterectomy, although the difference was not statistically significant. CONCLUSIONS: Primary PAS is often mistaken for chronic pulmonary thromboembolism. Surgical intervention is the mainstay of treatment for PAS, but the prognosis after surgery remains poor. Compared to isolated tumour resection, pulmonary endarterectomy seemed to yield a better survival rate.

Identification and functional study of type III-A CRISPR-Cas systems in clinical isolates of Staphylococcus aureus.

The CRISPR-Cas (clustered regularly interspaced short palindromic repeats [CRISPR]-CRISPR associated proteins [Cas]) system can provide prokaryote with immunity against invading mobile genetic elements (MGEs) such as phages and plasmids, which are the main sources of staphylococcal accessory genes. To date, only a few Staphylococcus aureus strains containing CRISPR-Cas systems have been identified, but no functional study in these strains has been reported. In this study, 6 clinical isolates of S. aureus with type III-A CRISPR-Cas systems were identified, and whole-genome sequencing and functional study were conducted subsequently. Genome sequence analysis revealed a close linkage between the CRISPR-Cas system and the staphylococcal cassette chromosome mec (SCCmec) element in five strains. Comparative sequence analysis showed that the type III-A repeats are conserved within staphylococci, despite of the decreased conservation in trailer-end repeats. Highly homologous sequences of some spacers were identified in staphylococcal MGEs, and partially complementary sequences of spacers were mostly found in the coding strand of lytic regions in staphylococcal phages. Transformation experiments showed that S. aureus type III-A CRISPR-Cas system can specifically prevent plasmid transfer in a transcription-dependent manner. Base paring between crRNA and target sequence, the endoribonuclease, and the Csm complex were proved to be necessary for type III-A CRISPR-Cas immunity.