Objective:To assess the left ventricular(LV) structure and systolic function in amateur marathon runners using real-time three-dimensional speckle tracking echocardiography(3D-STE) and analyze its correlation with the running volume.Methods:A total of 84 amateur marathon runners were recruited between January 2019 and October 2021 in Hangzhou and were divided into short-term (ST) group(≤6 months) and more extended-term(MET) group(>6 months–2 years) based on their time of participating in the marathon. Thirty-nine healthy volunteers were enrolled from the Affiliated Hospital of Hangzhou Normal University during the same period as a control group. The running volume of ST and MET runners were recorded, LV end-diastolic volume(EDV), end-systolic volume(ESV), LV mass(LVM), LV ejection fraction(LVEF), LV global longitudinal strain(GLS), global circumferential strain(GCS), global radial strain(GRS), global area strain (GAS), twist, and torsion were measured by conventional echocardiography and 3D-STE. The differences of those parameters among the three groups were compared. The correlation between 3D-STE parameters and the running volume was further analyzed.Results:In ST amateur marathon runners, LV EDV was higher compared with controls( P<0.05). Compared with ST and control groups, LV EDV, ESV, and LVM of MET runners were increased(all P<0.05). In addition, compared with control group, GLS of MET runners was increased( P<0.05). The LVEF, GCS, GRS, GAS, twist, and torsion showed no statistically significant differences among the three groups(all P>0.05). In amateur marathon runners LV EDV, ESV, LVM had statistically significant positive correlations with an average weekly running volume and total running volume (all P<0.01). Multivariate linear regression analysis showed that the total running volume was an independent correlation factor in LV EDV of amateur marathon runners (β=0.618, P<0.01). Conclusions:Amateur marathon runners participating in a short term marathon mainly show an increase in LV EDV, the longitudinal systolic function of the LV can be enhanced in the early stage of the marathon.

[摘 要] 目的：探讨miR-216b-5p对食管癌Eca109细胞顺铂（DDP）耐药性的影响及其作用机制。方法:采用qPCR法检测miR-216b-5p在食管癌细胞TE-1、KYSE-150、Eca109和耐药细胞Eca109/DDP中的表达水平。利用脂质体转染技术分别将miR-216b-5p mimic及mimic NC、自噬相关蛋白5（ATG5）过表达质粒转染到Eca109/DDP细胞中，用CCK-8、EdU法和FCM分别检测转染后细胞的增殖和凋亡；mRFP-eGFP-LC3双荧光标记实验检测mRFP-eGFP-LC3慢病毒感染后各组细胞自噬发生情况，WB法检测自噬相关蛋白LC3、Beclin 1和P62表达。用荧光素酶报告基因实验验证miR-216b-5p与ATG5的靶向关系，WB法检测ATG5的表达。建立裸鼠Eca109/DDP细胞移植瘤模型，观察miR-216b-5p过表达对移植瘤生长的影响。结果：miR-216b-5p在TE-1、KYSE-150、Eca109和Eca109/DDP细胞中均呈低表达（均P<0.05）。过表达miR-216b-5p可显著抑制Eca109/DDP细胞的增殖并诱导凋亡（均P<0.05），减少细胞中自噬小体数量（P<0.05），下调LC3Ⅱ/LC3Ⅰ比值和Beclin 1蛋白水平、上调P62蛋白水平（均P<0.05）。双荧光素酶报告基因实验证实miR-216b-5p靶向并负调控ATG5的表达（P<0.05），过表达ATG5可使miR-216b-5p mimic对Eca109/DDP细胞增殖、自噬的抑制作用和凋亡的诱导作用明显减弱（均P<0.05），自噬相关蛋白P62表达降低、LC3Ⅱ/LC3Ⅰ比值和Beclin 1表达升高（均P<0.05）。荷瘤实验结果表明，miR-216b-5p过表达可显著抑制裸鼠移植瘤的生长（P<0.05）。结论：miR-216b-5p过表达可逆转食管癌Eca109/DDP细胞对DDP的耐药性，其机制可能与靶向负调控ATG5表达并影响细胞自噬有关。

3' Untranslated Regions ; Animals ; Antagomirs ; metabolism ; Base Sequence ; Binding Sites ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Humans ; Mice ; MicroRNAs ; antagonists & inhibitors ; genetics ; metabolism ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; metabolism ; Rats ; Sequence Alignment ; Snail Family Transcription Factors ; antagonists & inhibitors ; genetics ; metabolism ; Stomach Neoplasms ; genetics ; pathology