Change and impact of left ventricular global longitudinal strain during transcatheter aortic valve implantation

BACKGROUND Although transcatheter aortic valve implantation(TAVI)is a safe and effective treatment for aortic stenosis,it still carries some risks,such as valve leaks,stroke,and even death.The left ventricular global longitudinal strain(LVGLS)measurement may be useful for the prediction of adverse events during this operation.AIM To explore the change of LVGLS during TAVI procedure and the relationship between LVGLS and perioperative adverse events.METHODS In this study,61 patients who had undergone percutaneous transfemoral TAVI were evaluated by transthoracic echocardiography.Before surgery,data on left ventricular ejection fraction(LVEF)and LVGLS were collected separately following balloon expansion and stent implantation.Difference in values of LVGLS and LVEF during preoperative balloon expansion(pre-ex),preoperative stent implantation(pre-im)and balloon expansion-stent implantation(ex-im)were also examined.Adverse events were defined as perioperative death,cardiac rupture,heart arrest,moderate or severe perivalvular leakage,significant mitral regurgitation during TAVI,perioperative moderate or severe mitral regurgitation,perioperative left ventricular outflow tract obstruction,reoperation,and acute heart failure.RESULTS The occurrence of perioperative adverse events was associated with differences in pre-ex LVGLS,but not with difference in pre-ex LVEF.There were significant differences between pre-LVGLS and ex-LVGLS,and between pre-LVGLS and im-LVGLS(P=0.037 and P=0.020,respectively).However,differences in LVEF were not significant(P=0.358,P=0.254);however differences in pre-ex LVGLS were associated with pre-LVGLS(P=0.045).Compared to LVEF,LVGLS is more sensitive as a measure of left heart function during TAVI and the perioperative period.Moreover,the differences in LVGLS were associated with the occurrence of perioperative adverse events,and changes in LVGLS were apparent in patients with undesirable LVGLS before the surgery.Furthermore,LVGLS is useful to predict changes in cardiac function during TAVI.CONCLUSION Greater attention should be paid to the patients who plan to undergo TAVI with normal LVEF but poor LVGLS.

Partial AZFc duplications not deletions are associated with male infertility in the Yi population of Yunnan Province,China

Objective:There are many reports on associations between spermatogenesis and partial azoospermia factor c(AZFc) deletions as well as duplications;however,results are conflicting,possibly due to differences in methodology and ethnic background.The purpose of this study is to investigate the association of AZFc polymorphisms and male infertility in the Yi ethnic population,residents within Yunnan Province,ChinaMethods:A total of 224 infertile patients and 153 fertile subjects were selected in the Yi ethnic population.The study was performed by sequence-tagged site plus/minus(STS+/) analysis followed by gene dosage and gene copy definition analysis.Y haplotypes of 215 cases and 115 controls were defined by 12 binary markers using single nucleotide polymorphism on Y chromosome(Y-SNP) multiplex assays based on single base primer extension technology.Results:The distribution of Y haplotypes was not significantly different between the case and control groups.The frequencies of both gr/gr(7.6% vs.8.5%) and b2/b3(6.3% vs.8.5%) deletions do not show significant differences.Similarly,single nucleotide variant(SNV) analysis shows no significant difference of gene copy definition between the cases and controls.However,the frequency of partial duplications in the infertile group(4.0%) is significantly higher than that in the control group(0.7%).Further,we found a case with sY1206 deletion which had two CDY1 copies but removed half of DAZ genes.Conclusions:Our results show that male infertility is associated with partial AZFc duplications,but neither gr/gr nor b2/b3 deletions,suggesting that partial AZFc duplications rather than deletions are risk factors for male infertility in Chinese-Yi population.

MiR-551b-5p Contributes to Pathogenesis of Vein Graft Failure via Upregulating Early Growth Response-1 Expression

Background： Vein graft failure （VGF） is a serious complication of coronary artery bypass graft, although the mechanism remains unclear. The study aimed to investigate the effects of microRNAs （miRNAs） on the endothelial dysfunction involved in VGF. Methods： Human umbilical vein endothelial cells （HUVECs） were subjected to mechanical stretch stimulation to induce endothelial dysfunction. Genome-wide transcriptome profiling was performed using the Human miRNA OneArray＂ V4 （PhalanxBio Inc., San Diego, USA）. The miRNA-messenger RNA （mRNA） network was investigated using gene ontology and Kyoto Encyclopedia of Genes and Genomes. The miR-55 1b-5p mimic and inhibitor were applied to regulate miR-55 lb-5p expression in the HUVECs. The 5-ethynyl-2＇-deoxyuridine assay, polymerase chain reaction （PCR）, and Western blotting （WB） were used to assess HUVECs proliferation, mRNA expression, and protein expression, respectively. The vein graft model was established in early growth response （Egr）-I knockout （KO） mice and wide-type （WT） C57BL/6J mice for pathological and immunohistochemical analysis. Endothelial cells isolated from the veins of WT and Egr-1 KO mice were subjected to mechanical stretch stimulation; PCR and WB were conducted to confirm the regulatory effect of Egr- 1 on Intercellular adhesion molecule （loam-1）. One-way analysis of variance and independent t-test were performed for data analysis. Results： Thirty-eight rniRNAs were differentially expressed in HUVECs after mechanical stretch stimulation. The bioinforrnatics analysis revealed that Egr-1 might be involved in VGF and was a potential target gene of miR-551b-5p. The mechanical stretch stimulation increased miR-55 1b-5p expression by 2.93 ± 0.08 told （t= 3.07, P 〈 0.05）, compared with the normal HUVECs. Transfection with the miR-551b-5p mimic or inhibitor increased expression of miR-551b-5p by 793.1 ± 171.6 fold （t = 13.84, P 〈 0.001） or decreased by 26.3% ± 2.4% （t= 26.39, P 〈 0.05） in the HUVECs, respectively. HUVECs proliferation and EGR-I mRNA expression were significantly suppressed by inhibiting miR-551b-5p expression （P 〈 0.05）. The lumens of the vein grafts in the Egr-1 KO mice were wider than that in the WT mice. lcam-I expression was suppressed significantly in the Egr-1 KO vein grafts （P 〈 0.05）. Conclusions： Increased miR-55 1b-5p expression leads to endothelial dysfunction by upregulating Egr-1 expression. EGR-1 KO can improve the function of a grafted vein through suppressing loam-1.

Differences of Matrix Metalloproteinase 2 Expression between Left and Right Ventricles in Response to Nandrolone Decanoate and/or Swimming Training in Mice

Background： Matrix metalloproteinase （MMP）-2 plays an important role in the remodeling of left ventricles （LVs） and right ventricles （RVs）. We investigated the differences of MMP-2 expression between LV and RV in response to nandrolone dccanoate （ND）, swimming training （ST）, and combined ND and ST （NS） in mice, based on their structural, functional, and biochemical characteristics. Methods： Totally 28 male C57B1 mice （6 weeks old; 20-23 g） were divided into four groups, including the control （n = 7）, ND （n = 6）, ST （n = 8）, and NS （n = 7） groups. After respective treatments for 8 weeks, echocardiographic examination was used to assess the cardiac structure and function. Van Gieson stain was used to examine the fibrosis of LV and RV in response to different treatments, and Western blotting analysis was performed to explore different MMP-2 expressions between LV and RV in response to ND and/or ST. Analysis of variance was used for comparing the four groups. Results： At 8 weeks, right ventricular dimension/body weight in the ND group was larger than the other three groups （F = 7.12, P 〈 0.05） according to the echocardiographic examination. Fibrosis induced by ND administration was increased more in RV （2.59%） than that in LV （2.21%）. MMP-2 expression of the ND group in RV was significantly greater than the control and NS groups in RV and the corresponding ND group in LV. Conclusion： The experimental data support the hypothesis that ND administration induces greater MMP-2 expression increase in RV compared to LV, leading to consequent RV dilation.