Trimethylamine N-oxide promotes abdominal aortic aneurysm by inducing vascular inflammation and vascular smooth muscle cell phenotypic switching

OBJECTIVE

Inflammation and vascular smooth muscle cell (VSMC) phenotypic switching are implicated in the pathogenesis of abdominal aortic aneurysm (AAA). Trimethylamine N-oxide (TMAO) has emerged as a crucial risk factor in cardiovascular diseases, inducing vascular inflammation and calcification. We aimed to evaluate the effect of TMAO on the formation of AAA.

APPROACH AND RESULTS

Here, we showed that TMAO was elevated in plasma from AAA patients compared with nonaneurysmal subjects by liquid chromatography‒mass spectrometry (LC‒MS) detection. Functional studies revealed that increased TMAO induced by feeding a choline-supplemented diet promoted Ang II-induced AAA formation. Immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), and Western blot analyses revealed that TMAO induced macrophage infiltration and inflammatory factor release. Conversely, inhibition of TMAO by supplementation with DMB suppressed AAA formation and the inflammatory response. Molecular studies revealed that TMAO regulated VSMC phenotypic switching. Flow cytometry analyses showed that TMAO induces macrophage M1-type polarization. Furthermore, pharmacological intervention experiments suggested that the nuclear factor-κB (NF-κB) signaling pathway was critical for TMAO to trigger AAA formation.

CONCLUSIONS

TMAO promotes AAA formation by inducing vascular inflammation and VSMC phenotypic switching through activation of the NF-κB signaling pathway. Thus, TMAO is a prospective therapeutic AAA target.

Identification and validation of pyroptosis-related genes as potential biomarkers for hypertrophic cardiomyopathy: A comprehensive bioinformatics analysis

Pyroptosis plays a key role in the death of cells including cardiomyocytes, and it is associated with a variety of cardiovascular diseases. However, the role of pyroptosis-related genes (PRGs) in hypertrophic cardiomyopathy (HCM) is not well characterized. This study aimed to identify key biomarkers and explore the molecular mechanisms underlying the functions of the PRGs in HCM. The differentially expressed genes were identified by GEO2R, and the differentially expressed pyroptosis-related genes (DEPRGs) of HCM were identified by combining with PRGs. Enrichment analysis was performed using the "clusterProfiler" package of the R software. Protein-protein interactions (PPI) network analysis was performed using the STRING database, and hub genes were screened using cytoHubba. TF-miRNA coregulatory networks and protein-chemical interactions were analyzed using NetworkAnalyst. RT-PCR/WB was used for expression validation of HCM diagnostic markers. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western Blot (WB) were used to measure and compare the expression of the identified genes in the cardiac hypertrophy model and the control group. A total of 20 DEPRGs were identified, which primarily showed enrichment for the positive regulation of cytokine production, regulation of response to biotic stimulus, tumor necrosis factor production, and other biological processes. These processes primarily involved pathways related to Renin-angiotensin system, Adipocytokine signaling pathway and NF-kappa B signaling pathway. Then, a PPI network was constructed, and 8 hub genes were identified. After verification analysis, the finally identified HCM-related diagnostic markers were upregulated gene protein tyrosine phosphatase non-receptor type 11 (PTPN11), downregulated genes interleukin-1 receptor-associated kinase 3 (IRAK3), and annexin A2 (ANXA2). Further GSEA analysis revealed these 3 biomarkers primarily related to cardiac muscle contraction, hypertrophic cardiomyopathy, fatty acid degradation and ECM - receptor interaction. Moreover, we also elucidated the interaction network of these biomarkers with the miRNA network and known compounds, respectively. RT-PCR/WB results indicated that PTPN11 expression was significantly increased, and IRAK3 and ANXA2 expressions were significantly decreased in HCM. This study identified PTPN11, IRAK3, and ANXA2 as pyroptosis-associated biomarkers of HCM, with the potential to reveal the development and pathogenesis of HCM and could be potential therapeutic targets.

MiR-431 promotes cardiomyocyte proliferation by targeting FBXO32 expression

BACKGROUND

The induction of cardiomyocyte (CM) proliferation is a promising approach for cardiac regeneration following myocardial injury. MicroRNAs (miRNAs) have been reported to regulate CM proliferation. In particular, miR-431 expression decreases during cardiac development, according to Gene Expression Omnibus (GEO) microarray data. However, whether miR-431 regulates CM proliferation has not been thoroughly investigated.

METHODS

We used integrated bioinformatics analysis of GEO datasets to identify the most significantly differentially expressed miRNAs. Real-time quantitative PCR and fluorescence in situ hybridization were performed to determine the miRNA expression patterns in hearts. Gain- and loss-of-function assays were conducted to detect the role of miRNA in CM proliferation. Additionally, we detected whether miR-431 affected CM proliferation in a myocardial infarction model. The TargetScan, miRDB and miRWalk online databases were used to predict the potential target genes of miRNAs. Luciferase reporter assays were used to study miRNA interactions with the targeting mRNA.

RESULTS

First, we found a significant reduction in miR-431 levels during cardiac development. Then, by overexpression and inhibition of miR-431, we demonstrated that miR-431 promotes CM proliferation in vitro and in vivo, as determined by immunofluorescence assays of 5-ethynyl-2'-deoxyuridine (EdU), pH3, Aurora B and CM count, whereas miR-431 inhibition suppresses CM proliferation. Then, we found that miR-431 improved cardiac function post-myocardial infarction. In addition, we identified FBXO32 as a direct target gene of miR-431, with FBXO32 mRNA and protein expression being suppressed by miR-431. FBXO32 inhibited CM proliferation. Overexpression of FBXO32 blocks the enhanced effect of miR-431 on CM proliferation, suggesting that FBXO32 is a functional target of miR-431 during CM proliferation.

CONCLUSION

In summary, miR-431 promotes CM proliferation by targeting FBXO32, providing a potential molecular target for preventing myocardial injury.

Recombinant erythropoietin protective and related effects on brain injury in premature infants

OBJECTIVE

The aim of this study was to investigate the protective effect of recombinant erythropoietin at different doses on brain injury in premature infants and the related effects on blood routine, liver function, intellectual development, mental development index (MDI), psychomotor development index (PDI), etc. PATIENTS AND METHODS: A total of 120 premature infants were divided into four groups, including experimental group A (n=30), experimental group B (n=30), experimental group C (n=30) and control group (n=30). The experimental group was treated with different doses of recombinant erythropoietin for brain injury protection of premature infants, while the control group with conventional methods.

RESULTS

There was no statistical significance in all test indicators of the four groups of patients before the intervention. After the intervention experiment, the S-100B index was p<0.05, and the erythropoietin (EPO) index was p<0.05. In the comparison of IL-6 indicators, the indicators of the experimental group were reduced after the comparison experiment, and there were significant differences, p<0.05. In neonatal behavior evaluation, there was a statistical difference between groups A and B and the control group (p<0.05), and no statistical significance was shown between group C and the control group (p>0.05). In the intelligence test comparison, the F value of the experimental group was 3.113 three months after treatment. After six months, the F value was 3.654. After nine months, the F value was 3.392 with p<0.05. In the comparison of blood routine indicators, the p-values of four indicators between groups were more than 0.05. In the comparison of liver function indexes, the indexes of groups A, B, and C were significantly changed before and after treatment, and the data after treatment were significantly different from those before treatment, p<0.05. In the comparison of development, there were no significant differences observed in the p-values of the two indicators of vigorous exercise and language in the experimental group.

CONCLUSIONS

Recombinant erythropoietin has a protective effect on infants with brain injury and can improve the intellectual development of premature infants, but has no significant effect on blood routine indicators. It can effectively improve the MDI, PDI, and related cytokines of premature infants, and has certain significance for the treatment of brain injury.

Predictive value of serum lncRNA MALAT1 for the recurrence of persistent atrial fibrillation after radiofrequency ablation

Objective: The authors investigated the predictive value of MALAT1 for persistent atrial fibrillation (PAF) recurrence after radiofrequency ablation. Methods: Serum MALAT1 level was determined. The correlation between MALAT1 and high-sensitivity C-reactive protein/left atrial diameter (LAD) was analyzed. The predictive value of MALAT1 was evaluated. The postoperative recurrence rate in patients with high/low MALAT1 was compared. Independent risk factors for postoperative recurrence were analyzed. Results: MALAT1 was elevated in PAF patients and positively correlated with high-sensitivity C-reactive protein/LAD. MALAT1/high-sensitivity C-reactive protein/LAD were enhanced in patients with recurrent PAF. Patients with high MALAT1 had a higher recurrence rate. Upregulated MALAT1 was an independent risk factor for postoperative PAF recurrence. Conclusion: Serum MALAT1 level >2.03 predicts postoperative recurrence of PAF, and PAF patients with high MALAT1 have a higher risk of postoperative recurrence.

Erratum: Therapeutic ultrasound combined with microbubbles improves atherosclerotic plaque stability by selectively destroying the intraplaque neovasculature: Erratum

[This corrects the article DOI: 10.7150/thno.39553.].

CircRNA Samd4 induces cardiac repair after myocardial infarction by blocking mitochondria-derived ROS output

Reactive oxygen species (ROS) derived from oxygen-dependent mitochondrial metabolism are the essential drivers of cardiomyocyte (CM) cell-cycle arrest in adulthood. Mitochondria-localized circular RNAs (circRNAs) play important roles in regulating mitochondria-derived ROS production, but their functions in cardiac regeneration are still unknown. Herein, we investigated the functions and underlying mechanism of mitochondria-localized circSamd4 in cardiac regeneration. We found that circSamd4 was selectively expressed in fetal and neonatal CMs. The transcription factor Nrf2 controlled circSamd4 expression by binding to the promoter of circSamd4 host gene. CircSamd4 overexpression reduced while circSamd4 silenced increased mitochondrial oxidative stress and subsequent oxidative DNA damage. Moreover, circSamd4 overexpression induced CM proliferation and prevented CM apoptosis, which reduced the size of the fibrotic area and improved cardiac function after myocardial infarction (MI). Mechanistically, circSamd4 reduced oxidative stress generation and maintained mitochondrial dynamics by inducing the mitochondrial translocation of the Vcp protein, which downregulated Vdac1 expression and prevented the mitochondrial permeability transition pore (mPTP) from opening. Our findings suggest that circSamd4 is a novel therapeutic target for heart failure after MI.

Protective activity of Malus doumeri leaf extract on H2O2-induced oxidative injury in H9C2 rat cardiomyocytes

In this study, Malus doumeri leaf extract (MDLE) was used to test its anti-oxidation capacity in vitro, it has been preliminarily analyzed for H2O2-induced oxidative damage in H9C2 cells and its main active components. The antioxidant capacity through DPPH (1, 1-Diphenyl-2-Picrylhydrazyl), ABTS+• [2,2,2'-azino-BIS-(3-ethylbenzo-thiazoline-6-sulfonic acid)] radical ion, •OH (hydroxyl radical), and • O 2 - (superoxide anion) were determined in vitro. The proliferation of H9C2 cells was examined by MTT [3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-Tetrazolium bromide]. MDA (malondialdehyde), SOD (superoxide dismutase), CAT (catalase), GSH (glutathione), and GSH-Px (glutathione peroxidase) were determined by colorimetry. Apoptosis induced by oxidative damage was detected by flow cytometry. The mRNA expression of antioxidant related genes of SOD, CAT, GSH, and GSH-Px were checked by qRT-PCR (quantitative real-time polymerase chain reaction). The MDLE main active components were analyzed by HPLC (high-performance liquid chromatography). MDLE had significant scavenging effects on DPPH, ABTS+•, •OH, and superoxide anion radicals in a concentration-dependent manner. H2O2 treatment could significantly lead to oxidative stress injury of H9C2 cells, and MDLE treatment significantly improved the degree of H9C2 cell damage, and showed a positive correlation with concentration. MDLE can also reduce apoptosis caused by oxidative damage. MDLE treatment could significantly reduce MDA content and increase CAT, SOD, GSH, and GSH-Px contents and expression. In addition, by HPLC analysis, the following six bioactive components were detected from MDLE: chlorogenic acid, isoquercitrin, quercetin, baicalin, and phloretin. Therefore, MDLE has a good protective effect on myocardial cells.

[Current status and challenges of anticoagulation management in extracorporeal membrane oxygenation]

The anticoagulant management of extracorporeal membrane oxygenation(ECMO) is facing great challenges. Complications related to the coagulation system such as bleeding or embolism are one of the main factors affecting the mortality of patients. How to control the dynamic balance between thrombosis and bleeding complications has become the top priority of ECMO management. This article reviews the coagulation changes during ECMO support, how to choose appropriate anticoagulant drugs and anticoagulation monitoring methods, aiming to explore the best anticoagulation strategy for ECMO patients.

POS1558-HPR INFLUENCING FACTORS ON WORK BURNOUT OF PRE-EXAMINATION AND TRIAGE NURSES UNDER THE NORMAL EPIDEMIC PREVENTION AND CONTROL

Background

Nurse is a high-risk groups work fatigue feeling, which seriously affects the quality of conventional work efficiency and bureden pressures for contradiction between nurses and patients especially during the COVID-19 pandemic.Normalized epidemic prevention and control during the preview triage nurse need to all patients to the hospital and the accompanying personnel carries on the preliminary screening.COVID-19 fixed point hospital preview triage nurse with an infected person contact, more prone to anxiety,depression, results in the decrease of efficiency, to treat the service object formulation work sense of fatigue performance, etc.

Objectives

To explore the influencing factors of work burnout of pre-test and triage nurses under normal epidemic prevention and control.

Methods

A total of 110 pre-test and triage nurses from 4 Grade-A hospitals in Shanxi Province were enrolled in this study. The general data questionnaire, Nurse Job Burnout Scale, Pittsburgh Sleep Quality Index Scale, Self-Rating Anxiety Scale and Self-Rating Depression Scale were investigated towork burnout of pre-examination and triage nurses. Comparison between groups using two Independent sample t-test and single factor variance analysis. Multiple regression were applied to analysis factors affecting nurse fatigue feeling dimensions by SPSS22.0. P values<0.05 were considered significant.

Results

As shown in Table 1, different professional title, department, and the sleep quality of preview triage nurses emotional exhaustion dimension comparison(P<0.001), different department nurses to personalized level dimension comparison(P<0.05), nurse personal accomplishment dimension comparison of different cultural levels(P<0.05). Professional title, working department, sleep quality and educational level were the influencing factors of job burnout of pre-test and triage nurses.

Table 1.

Univariate analysis of job burnout of pre-examination triage nurses from different dimensions.

ItemNumberJob BurnoutEmotional exhaustionDepersonalizationPersonal accomplishmentscoreF(t)PscoreF(t)PscoreF(t)Pgender0.0200.8880.1620.6890.3190.575 female10020.10±13.676.98±6.1528.40±13.41 male1021.00±12.088.20±9.5225.98±8.70age(year)5.5110.0074.1430.0210.7500.477 18~253020.33±12.408.40±7.3328.07±6.97 26~304013.60±11.624.00±3.5526.65±10.70 31~404027.00±13.489.20±6.9924.35±8.79marriage-0.9390.352-1.1550.2530.6150.541 unmarried5218.38±13.306.04±6.4027.00±9.99 married5821.79±13.578.03±6.4025.48±8.29job title5.7390.0062.3200.1080.6110.547 junior nurse5216.12±12.945.96±5.9827.26±8.33 senior nurse3819.68±12.536.63±6.1426.50±10.62 supervisor nurse2031.70±10.3810.90±7.2223.40±5.60work experience(year)1.2770.2920.9380.4290.6590.581 ＜12024.80±15.877.60±6.9827.90±5.67 1 ~32418.42±12.056.33±6.5124.25±13.00 4 ~93416.00±10.535.47±6.0324.69±9.16 10 ~203223.06±15.109.06±6.4328.00±7.46department-3.8750.000-2.3370.0230.4010.690 out-patient5413.81±10.505.11±4.3826.70±10.65 emergency5626.32±13.239.00±7.5025.71±7.42average working time per day(hour)0.7910.4591.1250.3322.1730.124 6~6.91815.33±7.925.11±5.2830.56±8.35 7~7.94420.26±13.616.43±7.2827.09±9.33 ≥84822.00±14.888.52±5.8123.61±8.62education degree-0.6430.523-1.0000.3222.4650.017 junior college1816.00±14.764.00±5.4836.50±8.43 college9220.51±13.427.33±6.4725.39±8.70SAS(score)2.0800.0421.6370.1080.4980.621 ≤503417.74±12.716.16±5.3327.12±8.74 >507625.65±13.759.18±8.1625.79±9.31SDS(score)0.2400.8110.8250.4130.4280.671 ≤507219.58±12.946.11±3.9626.58±9.66 >503820.50±13.857.61±7.4025.47±8.05PSQI(score)2.3790.0212.0290.047-0.5210.604 ≤74017.06±12.175.80±4.9826.69±9.33 >77025.65±14.089.35±8.0225.35±8.79

Conclusion

In the COVID-19 epidemic, managers should pay more attention to the main factors that affect the sense of exhaustion of pre-test and triage nurses, and take targeted intervention measures to alleviate the sense of exhaustion of nurses, so as to ensure the safety of nursing.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

3-iodothyronamine inhibits apoptosis induced by myocardial ischemia reperfusion via the Akt/FoxO1 signaling pathway

Background

This study investigated the potential effects of 3-iodothyronamine (T1AM) on myocardial ischemia reperfusion injury (MIRI) and the underlying molecular mechanisms.

Methods

A total of 16 adult male Sprague-Dawley rats were randomly divided into 4 groups and administered the following: control [60% dimethyl sulfoxide (DMSO) and 40% saline, pH 7.4], T1AM (25 mg/kg), T1AM (50 mg/kg), or T1AM (100 mg/kg). The rectal temperatures of the rats were measured at different time points. A further 30 adult male Sprague-Dawley rats were randomized and divided into the following 3 groups (n=10 in each group): sham operation, ischemia/reperfusion (I/R), and I/R + T1AM. In the I/R and I/R + T1AM groups, the left anterior descending (LAD) coronary artery of the rats were occluded for 0.5 hour to induce myocardial ischemia, followed by reperfusion for 3 hours in the I/R group. The electrocardiography (ECG), cardiac function, and 2,3,5-triphenyltetrazolium chloride (TTC) staining were examined in rats to evaluate the myocardial injury. The differences in the expression of apoptosis-related and Akt-FoxO1 signaling-related proteins were determined via Western blot.

Results

This work verified that T1AM reduced the body temperature of rats in a dose-dependent manner. Additionally, T1AM improved cardiac function and decreased the infarction size caused by MIRI. T1AM reduced the expression of biochemical parameters and apoptosis of myocardial cells. In addition, after treatment with T1AM, the expression of Glut1, pFoxO1 and Akt were reduced, while the expression of FoxO1 and PPARα were increased significantly.

Conclusions

Pretreatment of cardiomyocytes with T1AM inhibited apoptosis and protected against ischemia reperfusion injury via the Akt/FoxO1 signaling pathway.

Vitamin D receptor gene polymorphism predicts left ventricular hypertrophy in maintenance hemodialysis

Background

To verify that the single nucleotide polymorphisms (SNP) of vitamin D receptor (VDR) may lead to genetic susceptibility to left ventricular hypertrophy (LVH), the present study was designed to study four SNPs of VDR associated with LVH in maintenance hemodialysis (MHD) patients of Han nationality.

Methods

120 MHD patients were recruited at Department of Nephrology, Zhongnan Hospital of Wuhan University to analyze the expression of genotype, allele and haplotype of Fok I, Bsm I, Apa I and Taq I in blood samples, and to explore their correlation with blood biochemical indexes and ventricular remodeling.

Results

The results showed that the risks of CVD included gender, dialysis time, heart rate, SBP, glycated hemoglobin, calcium, iPTH and CRP concentration. Moreover, LAD, LVDd, LVDs, IVST and LVMI in B allele of Bsm I increased significantly. Fok I, Apa I and Taq I polymorphisms have no significant difference between MHD with LVH and without LVH. Further study showed that VDR expression level decreased significantly in MHD patients with LVH, and the B allele was positively correlated with VDR Expression.

Conclusion

VDR Bsm I gene polymorphism may predict cardiovascular disease risk of MDH patients, and provided theoretical basis for early detection and prevention of cardiovascular complications.

Hyperuricemia and hypertriglyceridemia indicate tubular atrophy/interstitial fibrosis in patients with IgA nephropathy and membranous nephropathy

PURPOSE

Hyperuricemia (HUA) and hypertriglyceridemia (HTG) were very common in chronic kidney disease (CKD) and associated with accelerated progression of CKD. This was a retrospective, cross-sectional study which aimed to explore the relationship between serum uric acid levels or triglyceride levels and tubular atrophy/interstitial fibrosis (proven by renal biopsy).

METHODS

The present study enrolled 229 CKD individuals who included 127 biopsy-proven primary IgA nephrology (IgAN) patients and 102 biopsy-proven primary membranous nephropathy (MN) patients. The baseline characteristics at the time of the kidney biopsy were collected. According to the serum uric acid (UA) or triglyceride (TG) whether it exceeds the normal reference range, patients were divided into non-HUA (n = 127), HUA (n = 102), non-HTG (n = 119), and HTG group (n = 110). Based on the extent of tubular atrophy/interstitial fibrosis, patients were divided into no/mild injury (T0, n = 127), moderate injury (T1, n = 102). Multivariable logistic regression for factors predicting moderate tubular atrophy/interstitial fibrosis was performed.

RESULTS

There were 127 IgAN and 102 MN cases among 229 patients in the present study. The prevalence of HUA was 44.5% (n = 102), 40.9% (n = 52), and 49.0% (n = 50) in all patients, IgAN patients and MN patients, respectively (P = 1.49). The prevalence of HTG was 48.0% (n = 110), 29.9% (n = 38), and 70.6% (n = 72) (P < 0.001), respectively, as well. Multivariate logistic regression analysis showed that HUA and HTG were independent risk factors for moderate tubular atrophy/interstitial fibrosis (HUA OR = 2.335, 95% CI = 1.147-4.755, P = 0.019; HTG OR = 2.646, 95% CI = 1.289-5.432, P = 0.008). The area under curve (AUC) of model 1 (HUA + eGFR + HTG + age + serum globulin + 24 h urinary protein, AUC = 0.876) was larger than the other two models; however, there was no significant difference among these models (all P > 0.05).

CONCLUSIONS

Hyperuricemia and hypertriglyceridemia, which were prevalent in CKD patients, were the independent risk factors for moderate tubular atrophy/interstitial fibrosis. HUA together with HTG could improve the value of diagnosis for moderate tubular atrophy/interstitial fibrosis to some extent.

MicroRNA-23b prevents aortic aneurysm formation by inhibiting smooth muscle cell phenotypic switching via FoxO4 suppression

AIMS

Phenotypic switching of vascular smooth muscle cells (VSMCs) is essential for the formation of abdominal aortic aneurysms (AAAs). MicroRNA-23b (miR-23b) has recently been shown to play a vital role in maintaining the VSMC contractile phenotype; however, little is known about the role of miR-23b in the formation of AAAs. Here, we investigated whether miR-23b prevents AAA formation by inhibiting VSMC phenotypic switching.

MATERIALS AND METHODS

We administered angiotensin II (Ang II, 1000 ng/kg/min) or vehicle to 10-12-week-old male apolipoprotein E knockout (ApoE^-/-) or C57BL/6J mice via subcutaneous osmotic minipumps for 4 weeks.

KEY FINDINGS

The expression of miR-23b was significantly reduced in the aorta during the early onset of AAA in angiotensin II-treated ApoE^-/- mice and in human AAA samples. In vitro experiments showed that the suppression of SMC contractile marker gene expression induced by Ang II was accelerated by miR-23b inhibitors but inhibited by mimics. In vivo studies revealed that miR-23b deficiency in Ang II-treated C57BL/6J mice aggravated the formation of AAAs in these mice compared with control mice; the opposite results were observed in miR-23b-overexpressing mice. Mechanistically, miR-23b knockdown significantly increased the expression of the transcription factor forkhead box O4 (FoxO4) during VSMC phenotypic switching induced by Ang II. In addition, a luciferase reporter assay showed that FoxO4 is a target of miR-23b in VSMCs.

SIGNIFICANCE

Our study revealed a pivotal role for miR-23b in protecting against aortic aneurysm formation by maintaining the VSMC contractile phenotype.

miR‑449a‑5p suppresses CDK6 expression to inhibit cardiomyocyte proliferation

Induction of cardiomyocyte (CM) proliferation is a promising approach for cardiac regeneration following myocardial injury. MicroRNAs (miRs) have been reported to regulate CM proliferation. In particular, miR‑449a‑5p has been identified to be associated with CM proliferation in previous high throughput functional screening data. However, whether miR‑449a‑5p regulates CM proliferation has not been thoroughly investigated. This study aimed to explore whether miR‑449a‑5p modulates CM proliferation and to identify the molecular mechanism via which miR‑449a‑5p regulates CM proliferation. The current study demonstrated that miR‑449a‑5p expression levels were significantly increased during heart development. Furthermore, the results suggested that miR‑449a‑5p mimic inhibited CM proliferation <em>in vitro</em> as determined via immunofluorescence for ki67 and histone H3 phosphorylated at serine 10 (pH3), as well as the numbers of CMs. However, miR‑449a‑5p knockdown promoted CM proliferation. CDK6 was identified as a direct target gene of miR‑449a‑5p, and CDK6 mRNA and protein expression was suppressed by miR‑449a‑5p. Moreover, CDK6 gain‑of‑function increased CM proliferation. Overexpression of CDK6 also blocked the inhibitory effect of miR‑449a‑5p on CM proliferation, indicating that CDK6 was a functional target of miR‑449a‑5p in CM proliferation. In conclusion, miR‑449a‑5p inhibited CM proliferation by targeting CDK6, which provides a potential molecular target for preventing myocardial injury.

[Validity and reliability of physical activity questionnaires in children and adolescents: a Meta-analysis]

Objective: This review is to systematically summarize the studies examining physical activity questionnaires in children and adolescents and assess the overall validity and reliability, providing evidence on epidemiology research of physical activity in youth. Methods: A meta-analysis was performed using Stata 14.0 software. PubMed/Medline and EMBASE databases using the following terms:'Physical Activity'AND (' Questionnaire'OR'Self-report'OR'Recall') AND'Valid*'AND (' Reliab*'OR'Reproducib*'OR'Sensitiv*'OR'Responsiv*') AND (' Child*' OR'Adolescen*'OR'Youth') were searched from January 2008 to December 2018. Articles meeting the inclusion criteria were screened and adopting 'COnsensusbased Standards for the selection of health status Measurement Instruments' to evaluate the quality of the included studies. Results: This review yielded 17 articles on 20 different physical activity questionnaires, the total number of 2 778 participants for validity study and 2 137 participants for reliability study. The combined values of correlation coefficients in validity study were 0.27 (95%CI: 0.23-0.31) for moderate-to-vigorous intensity physical activity, 0.24 (95%CI: 0.18-0.30) for moderate intensity physical activity, 0.33 (95%CI: 0.24-0.42) for vigorous intensity physical activity. The combined values of intraclass correlation coefficients in reliability study were 0.75 (95%CI: 0.68-0.83) for moderate-to-vigorous intensity physical activity, 0.56 (95%CI: 0.46-0.65) for moderate intensity physical activity, 0.68 (95%CI: 0.61-0.75) for vigorous intensity physical activity. Conclusion: Until now, no questionnaires were identified for good validity and reliability to assess the physical activity level in young population.

METTL3 Induces AAA Development and Progression by Modulating N6-Methyladenosine-Dependent Primary miR34a Processing

Identifying effective drugs to delay the progression of aortic aneurysms is a formidable challenge in vascular medicine. Methyltransferase-like 3 (METTL3) plays a key role in catalyzing the formation of N6-methyladenosine (m⁶A), but despite the functional importance of METTL3 and m⁶A in various fundamental biological processes, their roles in abdominal aortic aneurysm (AAA) are unknown. Here, we found that METTL3 knockdown in apolipoprotein E-deficient (ApoE^−/−) mice treated with angiotensin II suppressed the formation of AAAs, while METTL3 overexpression exerted the opposite effects. Similar results were obtained in a calcium chloride (CaCl₂)-induced mouse AAA model. Mechanistically, METTL3-dependent m⁶A methylation promoted primary microRNA-34a (miR-34a, pri-miR34a) maturation through DGCR8. Moreover, miR-34a overexpression significantly decreased SIRT1 expression and aggravated AAA formation, while miR-34a deficiency produced the opposite effects. In a rescue experiment, miR-34a knockdown or forced expression of SIRT1 partially attenuated the protective effects of METTL3 deficiency against AAA formation. Our studies reveal an important role for METTL3/m⁶A-mediated miR-34a maturation in AAA formation and provide a novel therapeutic target and diagnostic biomarker for AAA treatment.

Therapeutic ultrasound combined with microbubbles improves atherosclerotic plaque stability by selectively destroying the intraplaque neovasculature

Objective: The current antiangiogenic therapy for atherosclerotic plaques was mainly achieved by the use of antiangiogenic drugs, but serious side effects have limited the clinical application. The present study investigated whether therapeutic ultrasound (TUS) treatment with appropriate pressure could selectively deplete the neovasculature in vulnerable plaques to improve its stability with no side effects on the body; the underlying mechanisms were also explored.

Methods and Results: A mouse model of advanced atherosclerosis was generated by maintaining apolipoprotein E-deficient (ApoE-/-) mice on a hypercholesterolemic diet (HCD). Plaque, skeletal muscle, mesentery and skin tissue from 114 atheroma-bearing mice were subjected to sham therapy, an ultrasound application combined with microbubbles at four different ultrasound pressures (1.0, 2.0, 3.0, 5.0 MPa), or ultrasound at 5.0 MPa alone. Microvessel density (MVD) was assessed by immunofluorescence and immunohistochemical methods. The plaque necrotic center/fiber cap (NC/FC) ratio and vulnerability index were calculated to evaluate plaque vulnerability. Twenty-four hours after TUS treatment at 3.0 MPa, the MVD in the plaque was substantially decreased by 84% (p < 0.05), while there was almost no change in MVD and neovessel density (NVD) in normal tissues, including skeletal muscle, mesentery and skin. Additionally, a marked reduction in the number of immature vessels was observed in the plaques (reduced by 90%, p < 0.05), whereas the number of mature vessels was not significantly decreased. Furthermore, TUS treatment at 3.0 MPa significantly improved plaque stability, as reflected by the NC/FC ratio and vulnerability index, which may be due to the selective destruction of intraplaque neovascularization by TUS treatment, thereby decreasing the extravasation of erythrocytes and leading to vascular inflammation alleviation and thin-cap fibroatheroma reduction.

Conclusions: TUS treatment at 3.0 MPa selectively depleted plaque neovessels and improved the stability of vulnerable plaques through a reduction in erythrocyte extravasation and inflammatory mediator influx, with no significant effect on normal tissue.

Sirt1-inducible deacetylation of p21 promotes cardiomyocyte proliferation

Inducing cardiomyocyte proliferation is a hopeful approach for cardiac regeneration following myocardial infarction. Previous studies have shown that p21 inhibits the cardiomyocyte proliferation and cardiac regeneration. Deacetylation of p21 by Sirt1 deacetylase may reduce p21 abundance and remove p21-induced cell cycle arrest. However, whether p21 deacetylation and Sirt1 deacetylate control cardiomyocyte proliferation is unclear. Here, we show that acetylation of p21 induces cardiomyocyte proliferation arrest, whereas blocking the acetylation of p21 increases cardiomyocyte proliferation. P21 can be acetylated by Sirt1, and Sirt1 activate p21 ubiquitination through deacetylation. Additionally, overexpression of Sirt1 induces EdU-, pH3-, and Aurora B-positive cardiomyocytes in neonatal and adult mice. In contrast, depletion of Sirt1 reduces cardiomyocyte proliferation in vitro and in vivo. Moreover, Sirt1 protects cardiac function, reduces cardiac remodeling, inhibits cardiomyocyte apoptosis, and attenuates cardiomyocyte hypertrophy post-myocardial infarction. These results suggest that Sirt1-induced p21 deacetylation plays an essential role in cardiomyocyte proliferation and that it could be a novel therapeutic strategy for myocardial infarction.

SM22α (Smooth Muscle 22α) Prevents Aortic Aneurysm Formation by Inhibiting Smooth Muscle Cell Phenotypic Switching Through Suppressing Reactive Oxygen Species/NF-κB (Nuclear Factor-κB)

Objective- Vascular smooth muscle cell phenotypic transition plays a critical role in the formation of abdominal aortic aneurysms (AAAs). SM22α (smooth muscle 22α) has a vital role in maintaining the smooth muscle cell phenotype and is downregulated in AAA. However, whether manipulation of the SM22α gene influences the pathogenesis of AAA is unclear. Here, we investigated whether SM22α prevents AAA formation and explored the underlying mechanisms. Approach and Results- In both human and animal AAA tissues, a smooth muscle cell phenotypic switch was confirmed, as manifested by the downregulation of SM22α and α-SMA (α-smooth muscle actin) proteins. The methylation level of the SM22α gene promoter was dramatically higher in mouse AAA tissues than in control tissues. SM22α knockdown in ApoE^-/- (apolipoprotein E-deficient) mice treated with Ang II (angiotensin II) accelerated the formation of AAAs, as evidenced by a larger maximal aortic diameter and more medial elastin degradation than those found in control mice, whereas SM22α overexpression exerted opposite effects. Similar results were obtained in a calcium chloride-induced mouse AAA model. Mechanistically, SM22α deficiency significantly increased reactive oxygen species production and NF-κB (nuclear factor-κB) activation in AAA tissues, whereas SM22α overexpression produced opposite effects. NF-κB antagonist SN50 or antioxidant N-acetyl-L-cysteine partially abrogated the exacerbating effects of SM22α silencing on AAA formation. Conclusions- SM22α reduction in AAAs because of the SM22α promoter hypermethylation accelerates AAA formation through the reactive oxygen species/NF-κB pathway, and therapeutic approaches to increase SM22α expression are potentially beneficial for preventing AAA formation.

Magnetic Targeting Improves the Therapeutic Efficacy of Microbubble-Mediated Obstructive Thrombus Sonothrombolysis

Background Magnetic targeting may help microbubbles (MBs) reach obstructive thrombi and improve the efficacy of MB-mediated sonothrombolysis, but the role of magnetic targeting in MB-mediated sonothrombolysis remains elusive.

Objectives We investigate the feasibility and efficacy of magnetically targeted MB-mediated sonothrombolysis for the treatment of obstructive thrombi.

Materials and Methods Red and white thromboembolic models were established in vitro and in vivo. The models were randomly assigned to the control, ultrasound plus control MB (US + C-MB), ultrasound plus magnetic MB (US + M-MB), or US + M-MB + recombinant tissue-type plasminogen activator (r-tPA) groups and treated for 30 minutes. The recanalization rate, average blood flow velocity, hindlimb perfusion, and skeletal muscle injury marker levels were recorded.

Results The recanalization rate, average blood flow velocity, and hindlimb perfusion in the red and white thromboembolic models were all significantly higher in the US + M-MB and US + M-MB + r-tPA groups than in the control and US + C-MB groups both in vitro and in vivo. Moreover, the levels of the skeletal muscle injury markers were all significantly lower in the US + M-MB and US + M-MB + r-tPA groups than in the other two groups in vivo for both thromboembolic models. However, the thrombolytic effects of red thrombi performed better than those of white thrombi in the US + M-MB + r-tPA group.

Conclusion M-MB-mediated sonothrombolysis improves the efficacy of thrombolysis both in vitro and in vivo, and reduces tissue damage in clogging model; thus, this method may serve as a promising approach for treating thrombus-occlusive diseases.

Long noncoding RNA GAS5 induces abdominal aortic aneurysm formation by promoting smooth muscle apoptosis

Objective: Long noncoding RNAs (lncRNAs) may serve as specific targets for the treatment of abdominal aortic aneurysms (AAAs). LncRNA GAS5, functionally associated with smooth muscle cell (SMC) apoptosis and proliferation, is likely involved in AAA formation, but the exact role of GAS5 in AAA is unknown. We thus explored the contribution of GAS5 to SMC-regulated AAA formation and its underlying mechanisms.

Methods: Human specimens were used to verify the diverse expression of GAS5 in normal and AAA tissues. The angiotensin II (Ang II)-induced AAA model in ApoE-/- mice and the CaCl₂-induced AAA model in wild-type C57BL/6 mice were used. RNA pull-down and luciferase reporter gene assays were performed in human aortic SMCs to detect the interaction between GAS5 and its downstream targets of protein or microRNA (miR).

Results: GAS5 expression was significantly upregulated in human AAA specimens and two murine AAA models compared to human normal aortas and murine sham-operated controls. GAS5 overexpression induced SMC apoptosis and repressed its proliferation, thereby promoting AAA formation in two murine AAA models. Y-box-binding protein 1 (YBX1) was identified as a direct target of GAS5 while it also formed a positive feedback loop with GAS5 to regulate the downstream target p21. Furthermore, GAS5 acted as a miR-21 sponge to release phosphatase and tensin homolog from repression, which blocked the activation and phosphorylation of Akt to inhibit proliferation and promote apoptosis in SMCs.

Conclusion: The LncRNA GAS5 contributes to SMC survival during AAA formation. Thus, GAS5 might serve as a novel target against AAA.

[Assessment on the capacity for prevention and control programs for chronic non-communicable diseases in China, in 2014]

Objective: To assess the capacity of prevention and control on chronic non- communicable diseases (NCDs) in China. Methods: On-line questionnaire survey was adopted by 3 395 CDCs at provincial, municipal and county (district) levels and 3 000 primary health care units, and assess on capacity of policy, infrastructure, capacity of training and guidance, cooperation, surveillance, intervention and management, assessment and scientific research from September 2014 to March 2015. Results: (1) Capacity of policy: 23 (71.9%) provincial, 139 (40.6%) municipal and 919 (31.2%) county (district) governments or health administrative departments had existing plans for prevention and control of NCDs. (2) Capacity of infrastructure: 25 (78.1%) provincial, 136 (39.8%) municipal and 529 (18.0%) county (district) CDCs had set up departments dedicated to the prevention and control of NCDs, with 9 787 staff members, accounting for 5.0% of the total CDC personnel, working on NCDs prevention and control programs. 68.1% of the CDCs had special funding set for NCDs prevention and control. (3) Capacity of training and guidance: 2 485 CDCs (74.9%) held all kinds of training on prevention and control of NCDs. 2 571 (87.3%) CDCs at the county (district) level provided technical guidance for primary health care units. (4) Capacity of cooperation: 42.0% of the CDCs had experiences collaborating with the mass media. (5) Capacity of surveillance: 73.8% of the CDCs had set up programs for death registration while less than 50.0% of the CDCs had implemented surveillance programs on major NCDs and related risk factors. In terms of primary health care units, 32.4% of them had set up reporting system for newly developed stroke case and 29.9% of them having programs on myocardial infarction case reporting. (6) Capacity of intervention and management: 69.1% and 68.2% of the CDCs conducted individualized intervention programs on hypertension and diabetes, while less than 40.0% CDCs conducting intervention programs on other NCDs and risk factors. More than 90.0% of the primary health care units carried out follow-up surveys on hypertension and diabetes. However, only 17.4% and 13.7% of the CDCs working on hypertension and diabetes patient management programs while 83.7% and 80.4%, of them following the standardized guidelines for management, with successful rates of control as 59.2% and 55.2%, respectively. (7) Capacity of assessment: 32.4% of the CDCs or health administrations carried out evaluation programs related to the responses on NCDs. (8) Capacity of scientific research: the capacity on scientific research among provincial CDCs was apparently higher than that at the municipal or county (district) CDCs. Conclusions: Compared with the results of previous two surveys, the capacity on policies set for the prevention and control programs improved continuously, at all level NCDs, but remained relatively weak, especially at both county (district) and primary health care units.

Loss of Super-Enhancer-Regulated circRNA Nfix Induces Cardiac Regeneration After Myocardial Infarction in Adult Mice

Supplemental Digital Content is available in the text.

Background:

circRNAs (circular RNAs) are emerging as powerful regulators of cardiac development and disease, but their roles in cardiac regeneration are still unknown. This study used superenhancers to distinguish key circRNAs in the regulation of cardiac regeneration and explored the mechanisms underlying circRNA functions.

Methods:

We used integrated bioinformatics analysis of RNA sequencing data and superenhancer catalogs to identify superenhancer-associated circRNAs. Quantitative polymerase chain reactions and in situ hybridization were performed to determine the circRNA expression patterns in hearts. Gain- and loss-of-function assays were conducted to detect the role of circRNAs in cardiomyocyte proliferation and cardiac repair after myocardial infarction. Chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assays were used to determine the binding of Meis1 (Meis homeobox 1) on circNfix-associated superenhancers. RNA pulldown and luciferase reporter assays were used to study circRNA interactions with proteins and miRNAs (micro RNAs).

Results:

We identified a circRNA, Nfix circRNA (circNfix), that was regulated by a superenhancer and overexpressed in the adult heart in humans, rats, and mice. The transcription factor Meis1 bound to the superenhancer at the circNfix locus, and increased its expression. In vitro and in vivo, cardiomyocyte proliferation was increased by knockdown of circNfix, whereas it was inhibited by circNfix overexpression. Moreover, circNfix downregulation promoted cardiomyocyte proliferation and angiogenesis and inhibited cardiomyocyte apoptosis after myocardial infarction, attenuating cardiac dysfunction and improving the prognosis. Mechanistically, circNfix reinforced the interaction of Ybx1 (Y-box binding protein 1) with Nedd4l (an E3 ubiquitin ligase), and induced Ybx1 degradation through ubiquitination, repressing cyclin A2 and cyclin B1 expression. In addition, circNfix acted as a sponge for miR-214 to promote Gsk3β (glycogen synthase kinase 3 β) expression and repress β-catenin activity.

Conclusions:

Loss of superenhancer-regulated circNfix promotes cardiac regenerative repair and functional recovery after myocardial infarction by suppressing Ybx1 ubiquitin-dependent degradation and increasing miR-214 activity and thus may be a promising strategy for improving the prognosis after MI.

Inhibition of AZIN2-sv induces neovascularization and improves prognosis after myocardial infarction by blocking ubiquitin-dependent talin1 degradation and activating the Akt pathway

BACKGROUND

We previously found that loss of lncRNA-AZIN2 splice variant (AZIN2-sv) increases cardiomyocyte (CM) proliferation and attenuates adverse ventricular remodelling post-myocardial infarction (MI). However, whether inhibition of AZIN2-sv can simultaneously induce angiogenesis and thus improve prognosis after MI is unclear.

METHODS

We used in situ hybridization and quantitative PCR to determine AZIN2-sv expression in endothelial cells. Knockdown and overexpression were performed to detect the role of AZIN2-sv in endothelial cell function, angiogenesis and prognosis after MI. RNA pulldown, RNA immunoprecipitation and luciferase reporter assays were used to determine the interaction with talin1 (Tln1) protein and miRNA-214 (miR-214). DNA pulldown and chromatin immunoprecipitation (ChIP) assays were used to study AZIN2-sv binding to upstream transcription factors.

FINDINGS

AZIN2-sv was enriched in cardiac endothelial cells. The loss of AZIN2-sv reduced endothelial cell apoptosis and promoted endothelial sprouting and capillary network formation in vitro. Moreover, in vivo, the loss of AZIN2-sv induced angiogenesis and improved cardiac function after MI. Mechanistically, AZIN2-sv reduced Tln1 and integrin β1 (ITGB1) protein levels to inhibit neovascularization. AZIN2-sv activated the ubiquitination-dependent degradation of Tln1 mediated by proteasome 26S subunit ATPase 5 (PSMC5). In addition, AZIN2-sv could bind to miR-214 and suppress the phosphatase and tensin homologue (PTEN)/Akt pathway to inhibit angiogenesis. With regard to the upstream mechanism, Bach1, a negative regulator of angiogenesis, bound to the promoter of AZIN2-sv and increased its expression.

INTERPRETATION

Bach1-activated AZIN2-sv could participate in angiogenesis by promoting the PSMC5-mediated ubiquitination-dependent degradation of Tln1 and blocking the miR-214/PTEN/Akt pathway. Inhibition of AZIN2-sv induced angiogenesis and myocardial regeneration simultaneously, thus, AZIN2-sv could be an ideal therapeutic target for improving myocardial repair after MI. FUND: National Natural Science Foundations of China.

Long Non-coding RNA ECRAR Triggers Post-natal Myocardial Regeneration by Activating ERK1/2 Signaling

Reactivating post-natal myocardial regeneration potential may be a feasible strategy to regenerate the injured adult heart. Long non-coding RNAs (lncRNAs) have been implicated in regulating cellular differentiation, but whether they can elicit a regenerative response in the post-natal heart remains unknown. In this study, by characterizing the lncRNA transcriptome in human hearts during the fetal-to-adult transition, we found that 3,092 lncRNAs were differentially expressed, and we further identified a novel upregulated fetal lncRNA that we called endogenous cardiac regeneration-associated regulator (ECRAR), which promoted DNA synthesis, mitosis, and cytokinesis in post-natal day 7 and adult rat cardiomyocytes (CMs). Overexpression of ECRAR markedly stimulated myocardial regeneration and induced recovery of cardiac function after myocardial infarction (MI). Knockdown of ECRAR inhibited post-natal day 1 CM proliferation and prevented post-MI recovery. ECRAR was transcriptionally upregulated by E2F transcription factor 1 (E2F1). In addition, ECRAR directly bound to and promoted the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), resulting in downstream targets of cyclin D1 and cyclin E1 activation, which, in turn, activated E2F1. The E2F1-ECRAR-ERK1/2 signaling formed a positive feedback loop to drive cell cycle progression, and, therefore, it promoted CM proliferation. These findings indicated that our newly discovered ECRAR may be a valuable therapeutic target for heart failure.

The effects of ultrasound exposure on P-glycoprotein-mediated multidrug resistance in vitro and in vivo

Background

Multidrug resistance (MDR) is often responsible for the failure of chemotherapy treatment, and current strategies for cancer MDR are not adequately satisfying as to their efficacy and safety. In this study, we sought to determine the anti-MDR effects of ultrasound (US) irradiation and its underlying mechanisms against drug-resistance.

Methods

MDR variant MCF-7/ADR cell lines and endothelial cell lines were used to determine the appropriate ultrasound intensity for in vitro experiments. MCF-7/ADR cell and HEPG2/ADM cells were used to assess the anti-MDR effect of US irradiation. Intracellular adriamycin (ADM) accumulation, Cell viability, cell proliferation and cell apoptosis were evaluated after ADM + US treatment or ADM treatment alone. MCF-7/ADR xenograft mice were used to investigate the appropriate ultrasound intensity for in vivo experiments and its effect on the long-term prognosis. Underlining mechanisms by which ultrasound exposure reversing MDR phenotype were investigated both in vitro and in vivo.

Results

Combination of ADM and 0.74 W/cm² US irradiation enhanced ADM intracellular concentration and nuclear accumulation in MCF-7/ADR and HEPG2/ADM cells, compared to those treated with ADM alone. Enhanced cellular ADM uptake and nuclei localization was associated with increased cytotoxicity of ADM to ADM-resistant cells, lower ADM-resistant cell viability and proliferative cell ratio, and higher apoptotic cell ratio. More importantly, US exposure increased the effectiveness of ADM to inhibit tumor growth in MCF-7/ADR xenograft mice. Mechanistically, US exposure promoted ADM accumulation in MDR cells mainly through down-regulation of P-glycoprotein (P-gp), which is dependent on US-induced intracellular reactive oxygen species (ROS) production. US-induced oxidative stress promoted miR-200c-3p and miR-34a-3p expression by forming miR-200c/34a/ZEB1 double-negative feedback loop. Finally, US-induced miR-200c/34a overexpression decreased P-gp expression and reversed MDR phenotype.

Conclusion

US irradiation could reverse MDR phenotype by activating ROS-ZEB1-miR200c/34a-P-gp signal pathway. Our findings offer a new and promising strategy for sensitizing cells to combat MDR and to improve the therapeutic index of chemotherapy.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0900-6) contains supplementary material, which is available to authorized users.

[Technical specification for clinical application of critical ultrasonography]

Critical ultrasonography(CUS) is different from the traditional diagnostic ultrasound, the examiner and interpreter of the image are critical care medicine physicians. The core content of CUS is to evaluate the pathophysiological changes of organs and systems and etiology changes. With the idea of critical care medicine as the soul, it can integrate the above information and clinical information, bedside real-time diagnosis and titration treatment, and evaluate the therapeutic effect so as to improve the outcome. CUS is a traditional technique which is applied as a new application method. The consensus of experts on critical ultrasonography in China released in 2016 put forward consensus suggestions on the concept, implementation and application of CUS. It should be further emphasized that the accurate and objective assessment and implementation of CUS requires the standardization of ultrasound image acquisition and the need to establish a CUS procedure. At the same time, the standardized training for CUS accepted by critical care medicine physicians requires the application of technical specifications, and the establishment of technical specifications is the basis for the quality control and continuous improvement of CUS. Chinese Critical Ultrasound Study Group and Critical Hemodynamic Therapy Collabration Group, based on the rich experience of clinical practice in critical care and research, combined with the essence of CUS, to learn the traditional ultrasonic essence, established the clinical application technical specifications of CUS, including in five parts: basic view and relevant indicators to obtain in CUS; basic norms for viscera organ assessment and special assessment; standardized processes and systematic inspection programs; examples of CUS applications; CUS training and the application of qualification certification. The establishment of applied technology standard is helpful for standardized training and clinical correct implementation. It is helpful for clinical evaluation and correct guidance treatment, and is also helpful for quality control and continuous improvement of CUS application.

Assessment of Thrombotic Risk in Atrial Fibrillation with Ultrasound Molecular Imaging of P-Selectin

Molecular imaging of inflammatory mediators in atria may contribute to thrombotic risk assessment of atrial fibrillation (AF). We investigated the feasibility of ultrasound molecular imaging (UMI) targeted to P-selectin to assess thrombotic risk in AF. Rat AF models were established with rapid atrial pacing. Microbubbles targeted to P-selectin were injected into the rats, followed by left atrial (LA) UMI examination. Furthermore, P-selectin, platelets (PLTs), fibrin and tissue factor (TF) of LA were detected by histopathology and scanning electron microscopy. Plasma levels of P-selectin, thrombin-antithrombin complex (TAT) and prothrombin fragment 1 + 2 (F1 + 2) were measured by enzyme-linked immunosorbent assay. The data showed that P-selectin in LA was correlated with PLT, fibrin and TF (r = 0.735, p < 0.05; r = 0.827, p < 0.05; r = 0.785, p < 0.05, respectively). The plasma level of P-selectin was correlated with the expression of TAT and F1 + 2 (r = 0.866, p < 0.05; r = 0.916, p < 0.05, respectively). The contrast video intensity of adhered microbubbles targeted to P-selectin was correlated with the levels of P-selectin, PLT and fibrin in LA (r = 0.768, p < 0.05; r = 0.798, p < 0.05; r = 0.745, p < 0.05, respectively). In conclusion, P-selectin may serve as a biomarker for thrombotic risk in AF and can be quantified by UMI to assess thrombotic risk.

Abstract P3-03-14: ERα propelled drug-resistance-facilitating global DNA hypermethylation by promoting the DNMT1 gene expression

This abstract was not presented at the symposium.

Transforming growth factor-β1 promotes homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury

BACKGROUNDS

Acute ischemia reperfusion-induced kidney injury is a common cause of acute renal failure, and it is also an important cause of delayed recovery of transplanted kidney functions and even loss of function. However, there is no effective treatment method in clinical applications presently.

OBJECTIVE

The objective was to investigate effects of transforming growth factor-β1 on homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury.

METHODS

Effects of TGF-β1 over-expression in MSCs on expression of CXCR4 and chemotactic effect to SDF-1 were investigated by in vitro transmembrane chemotaxis. Anti-TGF-β1 antibody was incubated with ischemia reperfusion injury renal tissue homogenate and effects of anti-TGF-β1 antibody were observed. In addition, effects of TGF-β1 gene transfection and anti-CXCR4 antibody treatment in MSCs on expression of SDF-1/CXCR4 axis of renal tissues and damage repair were further explored.

RESULTS

Expression of TGF-β1 mRNA in the IRI group increased significantly, and MSCs transplantation could enhance expression of CXCR4 mRNA in rats of the IRI group, the expression of CXCR4 can be decreased by the anti-TGF-β1 antibody and the anti-CXCR4 antibody. TGF-β1 induced homing of MSCs in repair of renal ischemic reperfusion injury by regulating expression of CXCR4 on cell membranes. Blue fluorescence of DAPI-positive MSCs cells of renal parenchyma in the IRI+MSC group was enhanced significantly, which was significantly inhibited by anti-TGF-β1 and anti-CXCR4 antibody, and the inhibitory effect of anti-CXCR4 antibody was more obvious than that of anti-TGF-β1 antibody.

CONCLUSION

Transforming growth factor-β1 promotes homing of bone marrow mesenchymal stem cells in renal ischemia-reperfusion injury, which will provide useful data on role of TGF-β1 in regulating SDF-1/CXCR4 axis-induced MSCs homing.

Gemcitabine in combination with intraperitoneal cisplatin in advanced hepatobiliary cancers

e15666

Background: Standard chemotherapy for advanced hepatobiliary cancers remains undefined. This study was to observe the therapeutic effect of gemcitabine combined with intraperitoneal cisplatin for the treatment of advanced hepatobiliary cancers and analyze their toxicities. Methods: Patients with measurable hepatobiliary cancers were unrandomized into gemcitabine (GEM) + cisplatin (DDP) (GEM group) and epirubicin (EPI) + DDP (EPI group). GEM was used intravenously by infusion for 30 min with the dose to 1,000 mg/m2 on day 1 and 8; cisplatin was infused intraperitoneal with a dose of 25mg/m2 on day1, 3 and 5. Twenty-one days counted as one cycle. After 2 cycles, treatment efficacy and adverse events were evaluated according to WHO criteria. Results: A total of 76 patients were enrolled from May 2004 to May 2006, with 30 patients for EPI group and 46 patients for GEM group, and all the patients were eligible for effectiveness analysis. Among GEM group patients, there was no complete response. The partial response rate was 32.61% and clinical benefit response (CR+ PR +SD) was 67.39%. All those data mentioned above were significantly higher than that of EPI group. The main adverse re-ction was hematologic toxicity, while nonhematologic toxicity was mild. Conclusions: This study demonstrated that combination gemcitabine with intraperitoneal infusion of cisplatin was an effective and safety treatment for the patients with advanced hepatobiliary cancers.

No significant financial relationships to disclose.

The impact of CVB3 infection on host cell biology

CVB3 myocarditis can lead to dilated cardiomyopath (DCM). DCM is one of the leading causes of the need for heart transplantation, so it is important to understand the life cycle of CVB3 and its interactions with the host cell. Infection causes rapid death of host cardiomyocytes by altering normal cellular homeostasis for the efficient release of progeny virion. In this chapter, we will examine the impact that CVB3 replication has on host cell biology, from events that take place at receptor ligation to progeny virus release. The primary focus will be on the myriad of signalling pathways that are activated at all stages of virus replication and their downstream effects. We will also discuss some of the extracellular effects of infection as well as immune and matrixmetalloprotease activation. Interactions of host cell proteins with the 5' untranslated region (UTR) are required for translation and replication of CVB3. These interactions do not always benefit the virus since the interactions of a 28-kDa host protein with the 5' UTR are thought to be responsible for inhibitory activity against CVB3. Finally, we will discuss how the elucidation of the different stages of replication has provided the opportunity to develop novel strategies for combating CVB3 infection.

Inhibition of glycogen synthase kinase 3beta suppresses coxsackievirus-induced cytopathic effect and apoptosis via stabilization of beta-catenin

Coxsackievirus B3 (CVB3), a common human pathogen for viral myocarditis, induces a direct cytopathic effect (CPE) and apoptosis on infected cells. To elucidate the mechanisms that contribute to these processes, we studied the role of glycogen synthase kinase 3beta (GSK3beta). GSK3beta activity was significantly increased after CVB3 infection and addition of tyrosine kinase inhibitors blocked CVB3-triggered GSK3beta activation. Inhibition of caspase activity had no inhibitory effect on CVB3-induced CPE; however, blockage of GSK3beta activation attenuated both CVB3-induced CPE and apoptosis. We further showed that CVB3 infection resulted in reduced beta-catenin protein expression, and GSK3beta inhibition led to the accumulation and nuclear translocation of beta-catenin. Finally, we found that CVB3-induced CPE and apoptosis were significantly reduced in cells stably overexpressing beta-catenin. Taken together, our results demonstrate that CVB3 infection stimulates GSK3beta activity via a tyrosine kinase-dependent mechanism, which contributes to CVB3-induced CPE and apoptosis through dysregulation of beta-catenin.

Interaction of farnesylated PRL-2, a protein-tyrosine phosphatase, with the beta-subunit of geranylgeranyltransferase II

Protein of regenerating liver (PRL)-1, -2, and -3 comprise a subgroup of closely related protein-tyrosine phosphatases featuring a C-terminal prenylation motif conforming to either the consensus sequence for farnesylation, CAAX, or geranylgeranylation, CCXX. Yeast two-hybrid screening for PRL-2-interacting proteins identified the beta-subunit of Rab geranylgeranyltransferase II (betaGGT II). The specific interaction of betaGGT II with PRL-2 but not with PRL-1 or -3 occurred in yeast and HeLa cells. Chimeric PRL-1/-2 molecules were tested for their interaction with betaGGT II, and revealed that the C-terminal region of PRL-2 is required for interaction, possibly the PRL variable region immediately preceeding the CAAX box. Additionally, PRL-2 prenylation is prequisite for betaGGT II binding. As prenylated PRL-2 is localized to the early endosome, we propose that this is where the interaction occurs. PRL-2 is not a substrate for betaGGT II, as isoprenoid analysis showed that PRL-2 was solely farnesylated in vivo. Co-expression of the alpha-subunit (alpha) of GGT II, betaGGT II, and PRL-2 resulted in alpha/betaGGT II heterodimer formation and prevented PRL-2 binding. Expression of PRL-2 alone inhibited the endogenous alpha/betaGGT II activity in HeLa cells. Together, these results indicate that the binding of alphaGGT II and PRL-2 to betaGGT II is mutually exclusive, and suggest that PRL-2 may function as a regulator of GGT II activity.

Expression and significance of cell cycle-related proteins Cyclin Dl, CDK4, p27, E2F-l and Ets-1 in chondrosarcoma of the jaws

To elucidate the expression and significance of cell cycle-associated proteins in chondrosarcoma of the jaws, Cyclin Dl, CDK4, p27, E2F-l and Ets-l expressions were examined in chondrosarcoma and osteochondroma of the jaws by immunohistochemical ABC method. The results demonstrated that Cyclin Dl, CDK4, p27, E2F-1 and Ets-1 were positive 75% (15 of 20), 60% (12 of 20), 25% (5 of 20), 65% (13 of 20) and 60% (12 of 20) in chondrosarcoma of the jaws, respectively. There was no remarkable difference in the expression of these proteins among histological grades of the chondrosarcoma (P>0.05). In osteochondroma of the jaws, CDK4 and E2F with an equal positivity of 12.5% (1 of 8), whereas p27 was positive 75% (6 of 8). None of the osteochondroma cases was immunohistochemically positive for Cycin Dl and Ets-1. In addition, the positive rate of Cyclin Dl, CDK4, E2F-l and Ets-1 proteins was significantly higher, whereas p27 was lower in chondrosarcoma than in osteochondroma of the jaws (P<0.05). These data show that the expression of cell cycle regulatory proteins is altered in chondrosarcoma of the jaws: cyclin Dl, CDK4, E2F-1 and Ets-1 are over-expressed and p27 is low-expressed.

[The ultrastructure of bone morphogenetic protein 2 gene transfected human periodontal ligament fibroblasts]

OBJECTIVE

To observe the ultrastructure of bone morphogenetic protein 2 (BMP-2) gene transfected human periodontal ligament fibroblasts (HPDLFs).

METHODS

An expression vector for BMP-2 was transfected into HPDLFs by using Lipofect AMINE. The stable expression of BMP-2 was determined by in situ hybridization and immunohistochemistry. The ultrastructure of the transfected cells was examined by transmission electron microscope.

RESULTS

The results showed that the BMP-2 gene transfected cells showed expansive endoplasmic reticulum, incremental myelin sheath-like figures and matrix vesicles. The collagenous fibrillae was distributed widely intercellular.

CONCLUSIONS

The results suggests that BMP-2 gene transfection tends to accelerate HPDLFs into osteoblast-like cells.

[The biological effects of transforming growth factor-beta on human periodontal ligament fibroblasts]

OBJECTIVE

To evaluate the biological effects of transforming growth factor-beta (TGF-beta) on human periodontal ligament fibroblasts (HPDLFs).

METHODS

HPDLFs were primary cultured and examined for the effects of TGF-beta on its proliferation, alkaline phosphatase (ALP) activity, osteocalcin (OC) synthesis and formation of the mineralized nodules.

RESULTS

TGF-beta(0.0050-0.1000 mg/L) significantly stimulated the proliferation of HPDLFs. The ALP activity of HPDLFs was elevated evidently by 0.0050 mg/L TGF-beta. TGF-beta (0.0005-0.1000 mg/L) had no effects on OC synthesis and formation of the mineralized nodules of HPDLFs.

CONCLUSIONS

The effects of TGF-beta on HPDLFs are dose-dependent. TGF-beta can stimulate HPDLFs to express some of osteoblastic phenotype, and it lacks the abilility to promote maturation of the osteogenic phenotype.

Prenylation-dependent association of protein-tyrosine phosphatases PRL-1, -2, and -3 with the plasma membrane and the early endosome

PRL-1, -2, and -3 represent a novel class of protein-tyrosine phosphatase with a C-terminal prenylation motif. Although PRL-1 has been suggested to be associated with the nucleus, the presence of three highly homologous members and the existence of a prenylation motif call for a more detailed examination of their subcellular localization. In the present study, we first demonstrate that mouse PRL-1, -2, and -3 are indeed prenylated. Examination of N-terminal epitope-tagged PRL-1, -2, and -3 expressed in transiently transfected cells suggests that PRL-1, -2, and -3 are present on the plasma membrane and intracellular punctate structures. Stable Chinese hamster ovary cells expressing PRL-1 and -3 in an inducible manner were established. When cells were treated with brefeldin A, PRL-1 and -3 accumulated in a collapsed compact structure around the microtubule-organizing center. Furthermore, PRL-1 and -3 redistributed into swollen vacuole-like structures when cells were treated with wortmannin. These characteristics of PRL-1 and -3 are typical for endosomal proteins. Electron microscope immunogold labeling reveals that PRL-1 and -3 are indeed associated with the plasma membrane and the early endosomal compartment. Expression of PRL-3 is detected in the epithelial cells of the small intestine, where PRL-3 is present in punctate structures in the cytoplasm. When cells are treated with FTI-277, a selective farnesyltransferase inhibitor, PRL-1, -2, and -3 shifted into the nucleus. Furthermore, a mutant form of PRL-2 lacking the C-terminal prenylation signal is associated with the nucleus. These results establish that the primary association of PRL-1, -2, and -3 with the membrane of the cell surface and the early endosome is dependent on their prenylation and that nuclear localization of these proteins may be triggered by a regulatory event that inhibits their prenylation.

[Effects of TGF beta on BMP-2 gene transfection cells in vitro]

OBJECTIVE

To elucidate the mechanism of bone morphogenetic protein-2(BMP-2) and transforming growth factor beta(TGF beta) on cell differentiation.

METHODS

A phagemid expression vector for human BMP-2 (pBK-B2) was constructed and transfected into the NIH3T3 cells by using lipofectamine. Positive cell clones were selected with G418. The stable transfection and expression of BMP-2 were determined by using in situ hybridization and immunohistochemistry methods. The proliferativity of the transfected cells treated with TGF beta were assayed by MTT method. Alkaline phosphatase (ALP) and osteocalcin (OC) production were also measured.

RESULTS

The proliferation of the transfected cells was stimulated after being treated with TGF beta (50 ng/ml). But the ALP activity and OC production were inhibited.

CONCLUSION

The effects of TGF beta are closely related to many factors, and BMP and TGF beta may be synergistic in cell proliferation and differentiation.

Bezafibrate, an anti-hypertriglyceridemic drug, attenuates vascular hyperresponsiveness and elevated blood pressure in fructose-induced hypertensive rats

A high fructose diet induces hypertension, hyperinsulinemia - insulin resistance, and hypertriglyceridemia (syndrome X). In this study, we investigated the role of an abnormal lipid profile in mediating fructose-induced hypertension. We hypothesized that bezafibrate, a lipid-lowering drug, would reduce elevated blood pressure and inhibit increased vascular reactivity in fructose-fed rats. Male rats were placed on four different diets: group 1 was fed standard chow (n = 6); group 2 was fed 60% fructose (n = 5); group 3 was fed fructose plus bezafibrate (30 mg x kg(-1) x day(-1); drinking water; n = 5); and group 4 was fed standard chow plus bezafibrate (n = 6). In addition, the direct effects of very low density lipoprotein (VLDL) on vascular reactivity were examined. Bezafibrate treatment lowered blood pressure, free fatty acids, and triglycerides in the fructose-fed group, suggesting that lipid abnormalities play a role in the elevation of blood pressure in the fructose-induced hypertensive rat. Aortae from fructose-fed rats were hyperresponsive to the calcium channel agonist Bay K 8644, which was normalized with bezafibrate treatment. Incubation of aortae in a VLDL medium resulted in increased responsiveness to Bay K 8644, lending further support to lipid abnormalities altering vascular reactivity. An altered lipid profile evidenced by elevated triglycerides and free fatty acids is causally related to the development of high blood pressure and increased vascular reactivity in the fructose-induced hypertensive rat.