Peptide PDRPS6 attenuates myocardial ischemia injury by improving mitochondrial function.

Mitochondrial dynamics play a crucial role in myocardial ischemia-reperfusion (I/R) injury, where an imbalance between fusion and fission processes occurs. However, effective measures to regulate mitochondrial dynamics in this context are currently lacking. Peptide derived from the 40 S ribosomal protein S6 (PDRPS6), a peptide identified via peptidomics, is associated with hypoxic stress. This study aimed to investigate the function and mechanism of action of PDRPS6 in I/R injury. In vivo, PDRPS6 ameliorated myocardial tissue injury and cardiomyocyte apoptosis and decreased cardiac function induced by I/R injury in rats. PDRPS6 supplementation significantly reduced apoptosis in vitro. Mechanistically, PDRPS6 improved mitochondrial function by decreasing reactive oxygen species (ROS) levels, maintaining mitochondrial membrane potential (MMP), and inhibiting mitochondrial fission. Pull-down assay analyses revealed that phosphoglycerate mutase 5 (PGAM5) may be the target of PDRPS6, which can lead to the dephosphorylation of dynamin-related protein1 (Drp1) at ser616 site. Overexpression of PGAM5 partially eliminated the effect of PDRPS6 on improving mitochondrial function. These findings suggest that PDRPS6 supplementation is a novel method for treating myocardial injuries caused by I/R.

The influence of gender and wealth inequality on Alzheimer's disease among the elderly: A global study.

This study was designed to explore the relationship between Alzheimer's disease (AD) rates and socioeconomic conditions in 120 countries. We used mixed effect models to investigate the relationship between the rates of AD and socioeconomic data. This study is among the first studies to put forward statistical evidence of a significant association between AD and other dementias among the elderly and socioeconomic inequality. These findings could help to inform the policies to be designed to improve the quality of interventions for AD.

ELA-11 protects the heart against oxidative stress injury induced apoptosis through ERK/MAPK and PI3K/AKT signaling pathways.

Increasing evidence revealed that apoptosis and oxidative stress injury were associated with the pathophysiology of doxorubicin (DOX)-induced myocardial injury. ELABELA (ELA) is a newly identified peptide with 32 amino acids, can reduce hypertension with exogenous infusion. However, the effect of 11-residue furn-cleaved fragment (ELA-11) is still unclear. We first administrated ELA-11 in DOX-injured mice and measured the cardiac function and investigated the effect of ELA-11 in vivo. We found that ELA-11 alleviated heart injury induced by DOX and inhibited cardiac tissues from apoptosis. In vitro, ELA-11 regulated the sensitivity towards apoptosis induced by oxidative stress with DOX treatment through PI3K/AKT and ERK/MAPK signaling pathway. Similarly, ELA-11 inhibited oxidative stress-induced apoptosis in cobalt chloride (CoCl2)-injured cardiomyocytes. Moreover, ELA-11 protected cardiomyocyte by interacting with Apelin receptor (APJ) by using 4-oxo-6-((pyrimidin-2-ylthio) methyl)-4H-pyran-3-yl 4-nitrobenzoate (ML221). Hence, our results indicated a protective role of ELA-11 in oxidative stress-induced apoptosis in DOX-induced myocardial injury.

Genetic alterations, RNA expression profiling and DNA methylation of HMGB1 in malignancies.

The high mobility group box 1 (HMGB1) is a potential biomarker and therapeutic target in various human diseases. However, a systematic, comprehensive pan-cancer analysis of HMGB1 in human cancers remains to be reported. This study analysed the genetic alteration, RNA expression profiling and DNA methylation of HMGB1 in more than 30 types of tumours. It is worth noting that HMGB1 is overexpressed in malignant tissues, including lymphoid neoplasm diffuse large B-cell lymphoma (DLBC), pancreatic adenocarcinoma (PAAD) and thymoma (THYM). Interestingly, there is a positive correlation between the high expression of HMGB1 and the high survival prognosis of THYM. Finally, this study comprehensively evaluates the genetic variation of HMGB1 in human malignant tumours. As a prospective biomarker of COVID-19, the role that HMGB1 plays in THYM is highlighted.

Comprehensive analysis of the expression and prognosis for APOE in malignancies: A pan-cancer analysis.

Apolipoprotein E (APOE), a gene identified as one of the strongest genetic factors contributing to the risk determinant of developing late-onset Alzheimer's disease (AD), may also contribute to the risk of cancer. However, no pan-cancer analysis has been conducted specifically for the APOE gene. In this study, we investigated the oncogenic role of the APOE gene across cancers by GEO (Gene Expression Omnibus) and TCGA (The Cancer Genome Atlas). Based on the available data, we found that most cancer types overexpress APOE, and clear associations exist between the expression level of APOE and prognosis in tumor patients. The expression of APOE also correlates with certain gender-associated tumors including, ovarian cancer, uterine carcinosarcoma, and breast cancer. However, there is a significant negative association between cancer-associated fibroblast infiltration levels and the expression level of APOE in testicular germ cell tumors. Moreover, acute inflammatory response and protein-activation cascade-associated functions play an important role in the functional mechanisms of APOE. The present pan-cancer analysis of APOE shows that the protein phosphorylation, DNA methylation, and genetic alterations of APOE have a significant clinical relevance for survival prognosis and immune cell infiltration. This novel pan-cancer study outlines the current understanding of APOE oncogenic roles across thirty-three cancers and highlights the complex association between AD and cancers.

Identification of a novel native peptide derived from 60S ribosomal protein L23a that translationally regulates p53 to reduce myocardial ischemia-reperfusion.

Myocardial ischemia-reperfusion (I/R) is a severe disease，but its underlying mechanism is not fully elucidated and no effective clinical treatment is available. Utilizing intracellular peptidomics, we identified a novel native peptide PDRL23A (Peptide Derived from RPL23A), that is intimately related to hypoxic stress. We further show that PDRL23A effectively alleviates hypoxia-induced cardiomyocyte injury in vitro, along with improvements in mitochondrial function and redox homeostasis, including ROS accumulation, oxidative phosphorylation, and mitochondrial membrane potential. Strikingly, the in vivo results indicate that, short-term pretreatment with PDRL23A could effectively inhibit I/R-induced cardiomyocyte death, myocardial fibrosis and decreased cardiac function. Interestingly, PDRL23A was found to interact with 60 S ribosomal protein L26 (RPL26), hampering RPL26-governed p53 translation, and resulting in a reduction in the level of p53 protein, which in turn reduced p53-mediated apoptosis under hypoxic conditions. Collectively, a native peptide, PDRL23A, which translationally regulates p53 to protect against myocardial I/R injury, has been identified for the first time. Our findings provide insight into the adaptive mechanisms of hypoxia and present a potential new treatment for myocardial I/R.

A novel peptide HSP-17 ameliorates oxidative stress injury and apoptosis in H9c2 cardiomyocytes by activating the PI3K/Akt pathway.

Background: Oxidative stress and cell apoptosis play pivotal roles in the pathogenesis of doxorubicin (DOX)-induced myocardial injury. Heat shock protein-derived peptide (HSP-17) is a peptide which is low-expressed in DOX treated mouse heart tissue. It has high bioactivity and interspecies sequence consistency, and is predicted to have myocardial protective effect. Methods: Firstly, we added 1 µM DOX to H9c2 cell culture medium for 24 hours to construct the myocardial cytotoxicity model. Then we detected the effect of HSP-17 on DOX induced H9c2 cardiomyocyte injury by measuring cell viability and lactate dehydrogenase (LDH) level. In addition, reactive oxygen species (ROS) and tetraethylbenzimidazolylcarbocyanine iodide kits are used to evaluate the effect of the HSP-17 peptide on DOX-induced oxidative stress injury to cardiomyocytes, and the detection of apoptosis related proteins and flow cytometry were applied to detect the level of apoptosis. Furthermore, the protein expression levels [phosphorylated Akt (p-Akt) and phosphorylated PI3K (p-PI3K)] of the PI3K/Akt pathway were also detected by western blotting. Results: We found that the HSP-17 peptide can increase cell viability, protect mitochondrial potential, reduce LDH levels, and reduce ROS and cardiomyocyte apoptosis. In addition, we also observed that HSP-17 upregulated the expression level of p-Akt, and LY294002, a typical inhibitor of PI3K/Akt, was found to eliminate the protective roles of HSP-17. Conclusions: In conclusion, this study demonstrated that the HSP-17 peptide protected H9c2 cells against oxidative stress and apoptosis via PI3K/Akt pathway activation, which provides a new idea for the treatment of DOX-induced myocardial injury.

Exercise-induced peptide TAG-23 protects cardiomyocytes from reperfusion injury through regulating PKG-cCbl interaction.

Recent studies have revealed that proper exercise can reduce the risk of chronic disease and is beneficial to the body. Peptides have been shown to play an important role in various pathological processes, including cardiovascular diseases. However, little is known about the role of exercise-induced peptides in cardiovascular disease. We aimed to explore the function and mechanism of TAG-23 peptide in reperfusion injury and oxidative stress. Treatment with TAG-23 peptide significantly improved cell viability, the mitochondrial membrane potential, and ROS levels and reduced LDH release, the apoptosis rate and caspase 3 activation in vitro. In vivo, TAG-23 ameliorated MI and heart failure induced by I/R or DOX treatment. Pull-down assays showed that TAG-23 can bind to PKG . The TAG-23-PKG complex inhibited PKG degradation through the UPS. We also identified cCbl as the E3 ligase of PKG and found that the interaction between these proteins was impaired by TAG-23 treatment. In addition, we provided evidence that TAG-23 mediated Lys48-linked polyubiquitination and subsequent proteasomal degradation. Our results reveal that a novel exercise-induced peptide, TAG-23, can inhibit PKG degradation by serving as a competitive binding peptide to attenuate the formation of the PKG-cCbl complex. Treatment with TAG-23 may be a new therapeutic approach for reperfusion injury.

The Impact of COVID-19 on Primary Care General Practice Consultations in a Teaching Hospital in Shanghai, China.

Background: The COVID-19 (2019 novel coronavirus disease) pandemic is deeply concerning because of its massive mortality and morbidity, creating adverse perceptions among patients likely to impact on their overall medical care. Thus, we evaluated the impact of the COVID-19 pandemic on the pattern of primary care consultations within a Shanghai health district. Methods: A retrospective observational cohort study was performed, with data analyzed concerning the pattern of patient visits to general practitioners within the Tongren Hospital network (the sole provider of general practice to the population of 700,000). Data from all general practice consultations for adults were collected for the first 6 months of 2020, which included a 60-day lockdown period (January 24-March 24, 2020) and compared to corresponding data from the first 6 months of 2019. We evaluated changes to the numbers and patterns of primary care consultations, including subgroup analysis based on age, sex, and primary diagnosis. Results: A substantial reduction in patient visits, associated with increased median age, was observed during the first wave of the pandemic in the first 6 months of 2020, compared to the same interval during 2019. Additionally, reduced reappointments and waiting times, but increased costs per visit were observed. When analyzed by primary disease diagnosis, patient visits were reduced for all the major systems. The most striking visit reductions were in cardiovascular, respiratory, endocrine, and gastrointestinal diseases. However, psychological disorders were increased following lockdown, but there was also a dramatic fall in consultations for depression. Reduced monthly patient numbers correlated with both rate of reappointment and average waiting time during the first 6 months of both 2019 and 2020, but an inverse correlation was observed between cost per visit and monthly patient numbers. Specifically during the lockdown period, there was ~50% reduced patient visits. Conclusions: The lockdown has had a serious impact on patients' physical and psychological health. Our analysis provides objective health-related data that may inform the current controversy concerning the balance between the detrimental effects of the use of lockdown vs. the use of a more targeted approach to eliminate viral transmission. These data may improve decision-making in medical practice, policy, and education.

Exercise-induced peptide EIP-22 protect myocardial from ischaemia/reperfusion injury via activating JAK2/STAT3 signalling pathway.

Recent studies have revealed that exercise has myocardial protective effects, but the exact mechanism remains unclear. Studies have increasingly found that peptides play a protective role in myocardial ischaemia-reperfusion (I/R) injury. However, little is known about the role of exercise-induced peptides in myocardial I/R injury. To elucidate the effect of exercise-induced peptide EIP-22 in myocardial I/R injury, we first determined the effect of EIP-22 on hypoxia/reperfusion (H/R)- or H2 O2 -induced injury via assessing cell viability and lactate dehydrogenase (LDH) level. In addition, reactive oxygen species (ROS) accumulation and mitochondrial membrane potential (MMP) was assessed by fluorescence microscope. Meanwhile, Western blot and TUNEL methods were used to detect apoptosis level. Then, we conducted mice I/R injury model and verified the effect of EIP-22 by measuring cardiac function, evaluating heart pathology and detecting serum LDH, CK-MB and cTnI level. Finally, the main signalling pathway was analysed by RNA-seq. In vitro, EIP-22 treatment significantly improved cells viabilities and MMP and attenuated the LDH, ROS and apoptosis level. In vivo, EIP-22 distinctly improved cardiac function, ameliorated myocardial infarction area and fibrosis and decreased serum LDH, CK-MB and cTnI level. Mechanistically, JAK/STAT signalling pathway was focussed by RNA-seq and we confirmed that EIP-22 up-regulated the expression of p-JAK2 and p-STAT3. Moreover, AG490, a selective inhibitor of JAK2/STAT3, eliminated the protective roles of EIP-22. The results uncovered that exercise-induced peptide EIP-22 protected cardiomyocytes from myocardial I/R injury via activating JAK2/STAT3 signalling pathway and might be a new candidate molecule for the treatment of myocardial I/R injury.

Peptide Szeto­Schiller 31 ameliorates doxorubicin­induced cardiotoxicity by inhibiting the activation of the p38 MAPK signaling pathway.

Oxidative stress serves a key role in doxorubicin (DOX)­induced cardiotoxicity. The peptide Szeto­Schiller (SS)31 is an efficacious antioxidant with the capacity to reduce mitochondrial reactive oxygen species (ROS) levels and scavenge free radicals. Although SS31 is involved in the pathophysiological process of various cardiovascular diseases, the role of SS31 in DOX­induced cardiotoxicity remains unclear. To explore the effects of SS31 in DOX­induced cardiotoxicity, the present study first constructed DOX­induced cardiotoxicity models, in which H9c2 cells were incubated with 1 µM DOX for 24 h and C57BL/6 mice were administered DOX (20 mg/kg cumulative dose). The results of various assays in these models demonstrated that SS31 exhibited a cardioprotective effect in vitro and in vivo by attenuating the level of ROS, stabilizing the mitochondrial membrane potential and ameliorating myocardial apoptosis as well as fibrosis following treatment with DOX. Mechanistically, the results of the present study revealed that the p38 MAPK signaling pathway was inhibited by SS31 in DOX­treated H9c2 cells, which was associated with the cardioprotective function of SS31. In addition, P79350, a selective agonist of p38 MAPK, reversed the protective effects of SS31. Taken together, these results demonstrated the effects of SS31 on ameliorating DOX­induced cardiotoxicity and indicated its potential as a drug for the treatment of DOX­induced cardiotoxicity.

Peptidomics analysis revealed that a novel peptide VMP­19 protects against Ang II­induced injury in human umbilical vein endothelial cells.

Vascular endothelial dysfunction is a vital pathological change in hypertension, which is mainly caused by apoptosis and oxidative stress injury of vascular endothelial cells. Peptidomics is a method for the direct analysis of small bioactive peptides in various biological samples using liquid chromatography­mass spectrometry (MS)/MS. Given the advantages of the low molecular weight, optimum targeting and easy access to cells, peptides have attracted extensive attention in the field of drug research. However, to the best of our knowledge, little is currently known regarding the role of peptides in vascular endothelial injury. In order to investigate the peptides involved in vascular endothelial protection, MS was used to analyze the peptide profiles in the supernatant of human umbilical vein endothelial cells (HUVECs) stimulated by Ang II. The results revealed that 211 peptides were identified, of which six were upregulated and 13 were downregulated when compared with the control group. Subsequently, the present study analyzed the physical and chemical properties and biological functions of identified peptides by bioinformatics, and successfully screened a peptide (LLQDSVDFSLADAINTEFK) named VMP­19 that could alleviate the apoptosis and oxidative stress injury of HUVECs induced by Ang II. In conclusion, to the best of our knowledge, the present study was the first to use peptidomics to analyze the peptide profiles of supernatant secreted by HUVECs, and revealed that the novel peptide VMP­19 could protect HUVECs from apoptosis and oxidative stress injury. The results of the present study could provide novel insights into treatment strategies for hypertension.

Circular RNA Arhgap12 modulates doxorubicin-induced cardiotoxicity by sponging miR-135a-5p.

AIM: This study aimed to investigate the regulatory role of differentially-expressed circular RNAs (circRNAs) in mouse cardiomyocytes during doxorubicin (DOX)-induced cardiotoxicity. MAIN METHODS: Two groups of mice were injected with equal volumes (0.1 mL) of normal saline and DOX. Mouse heart tissue was isolated and digested for total RNA extraction and then subjected to next-generation RNA-sequencing. Expression profiles of circRNAs and circRNA-miRNA-mRNA networks were also constructed. Overall, 48 upregulated and 16 downregulated circRNAs were found to be statistically significant (p < 0.05) in the DOX-injected group. Bioinformatics analysis revealed several potential biological pathways that might be related to apoptosis caused by DOX-induced cardiotoxicity. In addition, using qRT-PCR, we found that a circRNA coded by the Arhgap12 gene, termed circArhgap12, was upregulated in the mouse heart tissue upon DOX intervention. CircArhgap12 enhanced apoptotic cell rate, as assessed using terminal-deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay, and increased reactive oxygen species and malondialdehyde release as well as superoxide dismutase and caspase-3 activation. Using a luciferase reporter assay, we found that circArhgap12 could sponge miR-135a-5p. In rat primary cardiomyocytes, we found that si-circArhgap12 promoted apoptosis and oxidative stress by sponging the miR-135a-5p inhibitor. Using bioinformatics analysis and luciferase reporter assay, we found that miR-135a-5p might have a potential target site for ADCY1 mRNA. KEY FINDINGS: Our research demonstrated that the expression profile of circRNAs was modified significantly and that circArhgap12 might play a competitive role among endogenous RNAs in mouse cardiomyocytes during DOX-induced cardiotoxicity. SIGNIFICANCE: Our study may provide a preliminary understanding of DOX-induced cardiotoxicity modulated by circRNA and its competing endogenous RNAs network.

Peptidomics Analysis Reveals Peptide PDCryab1 Inhibits Doxorubicin-Induced Cardiotoxicity.

Doxorubicin (DOX) is limited due to dose-dependent cardiotoxicity. Peptidomics is an emerging field of proteomics that has attracted much attention because it can be used to study the composition and content of endogenous peptides in various organisms. Endogenous peptides participate in various biological processes and are important sources of candidates for drug development. To explore peptide changes related to DOX-induced cardiotoxicity and to find peptides with cardioprotective function, we compared the expression profiles of peptides in the hearts of DOX-treated and control mice by mass spectrometry. The results showed that 236 differential peptides were identified upon DOX treatment, of which 22 were upregulated and 214 were downregulated. Next, we predicted that 31 peptides may have cardioprotective function by conducting bioinformatics analysis on the domains of each precursor protein, the predicted score of peptide biological activity, and the correlation of each peptide with cardiac events. Finally, we verified that a peptide (SPFYLRPPSF) from Cryab can inhibit cardiomyocyte apoptosis, reduce the production of reactive oxygen species, improve cardiac function, and ameliorate myocardial fibrosis in vitro and vivo. In conclusion, our results showed that the expression profiles of peptides in cardiac tissue change significantly upon DOX treatment and that these differentially expressed peptides have potential cardioprotective functions. Our study suggests a new direction for the treatment of DOX-induced cardiotoxicity.

A simulation training course for family medicine residents in China managing COVID-19.

BACKGROUND AND OBJECTIVES: As a result of the pandemic, family physicians face the additional challenge of navigating COVID-19. The aim of this study was to provide simulated training for best-practice management of COVID-19 presentations for residency program trainees in Shanghai, China. METHOD: A simulated suspected COVID-19 case was designed on the basis of a real patient. The simulation included: pre­ and post-simulation surveys, a PowerPoint presentation, simulation practice, debriefing and reflection. Improvement in survey outcomes was assessed using a paired t-test. RESULTS: A total of 25 trainees participated in the simulation, consisting of first-, second- and third-year family medicine residents. Significant improvement was observed in their knowledge of COVID-19, and sub-analysis showed that all three grades of residents improved their knowledge significantly. Ninety-six per cent of participants believed the simulation was very helpful. DISCUSSION: The simulation scenario improves crisis management skills for family physicians managing the high risk of transmission of respiratory infectious diseases. Higher-order learning outcomes will be explored in future training programs.

Role of lncRNA uc.457 in the differentiation and maturation of cardiomyocytes.

Congenital heart disease (CHD) is the most common type of birth defect, and the leading cause of fetal mortality. The long noncoding RNA (lncRNA) uc.457 is differentially expressed in cardiac tissue from patients with a ventricular septal defect; however, its role in cardiac development and CHD remains unknown. In the present study, the role of uc.457 in the differentiation and maturation of cardiomyocytes was investigated. Bioinformatics approaches were employed to analyze putative transcription factor (TF) regulation, histone modifications and the biological functions of uc.457. Subsequently, uc.457 overexpression and small interfering RNA­mediated knockdown were performed to evaluate the functional role of the lncRNA in the dimethyl sulfoxide­induced differentiation of P19 cells into cardiomyocytes. Bioinformatics analyses predicted that uc.457 binds to TFs associated with cardiomyocyte growth and cardiac development. Cell Counting Kit­8 assays demonstrated that uc.457 overexpression inhibited cell proliferation, whereas knockdown of uc.457 enhanced the proliferation of differentiating cardiomyocytes. Additionally, reverse transcription­quantitative polymerase chain reaction and western blot analyses revealed that overexpression of uc.457 suppressed the mRNA and protein expression of histone cell cycle regulation defective homolog A, natriuretic peptide A, cardiac muscle troponin T and myocyte­specific enhancer factor 2C. Collectively, the results indicated that overexpression of uc.457 inhibited the differentiation and proliferation of cardiomyocytes, suggesting that dysregulated uc.457 expression may be associated with CHD.

Long noncoding RNA uc.4 inhibits cell differentiation in heart development by altering DNA methylation.

In previous studies, we have demonstrated that long noncoding RNA uc.4 may influence the cell differentiation through the TGF-ß signaling pathway, suppressed the heart development of zebrafish and resulting cardiac malformation. DNA methylation plays a significant role in the heart development and disordered of DNA methylation may cause disruption of control of gene promoter. In this study, methylated DNA immunoprecipitation was performed to identify the different expression levels of methylation regions. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were also performed to identify the possible biological process and pathway that uc.4 may join, associated with Rap1 signaling pathway, gonadotropin-releasing hormone signaling pathway, and Calcium signaling pathway. We found that the distribution of differentially methylated regions peaks was mainly located in intergenic and intron regions. Altogether, our result showed that differentially methylated genes are significantly expressed in uc.4-overexpression cells, providing valuable data for further exploration of the role of uc.4 in heart development.

Expression profile of long non­coding RNAs in cardiomyocytes exposed to acute ischemic hypoxia.

Acute myocardial infarction (AMI) is a life­threatening disease and seriously influences patient quality of life. Long non­coding RNAs (lncRNAs), an emerging class of non­coding genes, have attracted attention in research, however, whether lncRNAs serve a function in acute ischemic hypoxia remains to be elucidated. In the present study, an lncRNA microarray was used to analyze differential lncRNA expression in acute ischemic hypoxia. A total of 323 lncRNAs were identified, 168 of which were upregulated and 155 of which were downregulated. Gene Ontology and Pathway analyses were also used to identify the potential functions of dysregulated lncRNAs; it was predicted that these dysregulated lncRNAs may contribute to the initiation of AMI. It was demonstrated that an lncRNA termed sloyfley may influence acute ischemic hypoxia through its neighboring gene Peg3, which has been linked to brain ischemia hypoxia. In summary, the present study identified numerous lncRNAs, which may provide further opportunities for the development of novel therapeutic strategies.

An alternative under-valve approach to ablate right-sided accessory pathways.

BACKGROUND: Right-sided accessory pathway (RAP) ablation is sometimes challenging. OBJECTIVE: Our study aimed to demonstrate an alternative ablation approach to RAPs under the tricuspid valve, especially when the conventional ablation attempts at the atrial side failed. METHODS: Twelve patients with RAPs were enrolled, 8 of whom had previously failed ablation. With the help of a long sheath, the under-valve approach was attempted in 3 patients during tachycardia, in 2 patients during ventricular pacing, and in 7 patients during sinus rhythm. Three-dimensional electroanatomic mapping was performed in 3 patients during their repeat procedures. RESULTS: The acute outcomes of the procedures in all patients were successful. Patients were free of tachycardia or recurrence of accessory pathway conduction during a median follow-up of 12.5 months (range 7-45 months). No complications were found during the procedure or follow-up period. CONCLUSION: Radiofrequency ablation under the tricuspid valve to eliminate RAPs is feasible because of its stable contact and the accurate ablation of the ventricular insertion site. It provides an alternative approach to tough RAP ablation.

Altered DNA Methylation of Long Noncoding RNA uc.167 Inhibits Cell Differentiation in Heart Development.

In previous studies, we have demonstrated the function of uc.167 in the heart development. DNA methylation plays a crucial role in regulating the expression of developmental genes during embryonic development. In this study, the methylomic landscape was investigated in order to identify the DNA methylation alterations. Methylated DNA immunoprecipitation (MeDIP) was performed to examine the differences in methylation status of overexpressed uc.167 in P19 cells. GO and KEGG pathway analyses of differentially methylated genes were also conducted. We found that the distribution of differentially methylated regions (DMRs) peaks in different components of genome was mainly located in intergenic regions and intron. The biological process associated with uc.167 was focal adhesion and Rap1 signaling pathway. MEF2C was significantly decreased in uc.167 overexpressed group, suggesting that uc.167 may influence the P19 differentiation through MEF2C reduction. Taken together, our findings revealed that the effect of uc.167 on P19 differentiation may be attributed to the altered methylation of specific genes.