Objective:To investigate the effects of 10° head up tilt bed rest (HUT) on human cardiac function via 3D speckle tracking echocardiography (3D-STE), and to study the difference in cardiac function under the submaximal exercise load between the horizontal position and 10° HUBR.Methods:Thirty young healthy volunteers were recruited as the subjects, who were randomly divided into an 10° HUT exercise group and horizontal exercise group with 15 subjects in each. Subjects in both groups were asked to ride the bicycle ergometer in the 10° HUBR position and supine position respectively. The load started with 50 W and was increased by 25 W every 3 min until it reached the maximum of 125 W. Before the exercise (resting state), 1 min after the load was increased each time, and 3 min after exercise (recovery period), the following indices were collected: ①basic cardiac function indices: heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP), ②conventional cardiac ultrasound indices: left ventricular ejection fraction (LVEF), stroke volume (SV) and cardiac output (CO), ③left ventricular strain indices: global longitudinal strain (GLS), global circumferential strain (GCS), and global area strain (GAS) measured by 3D-SET. The changes of these indices in the 2 groups of subjects under different exercise loads were observed.Results:The differences in the major effect of the basic heart indices (HR, SBP and DBP), conventional cardiac ultrasound indices (LVEF, SV and CO) and left ventricular strain indices (GLS, GCS and GAS) in response to the exercise load were statistically significant ( F=194.90, 113.66, 17.19, P=0.017, 0.018, 0.001). With the increase of the exercise load, the basic heart indices and conventional cardiac ultrasound indices kept rising, the left ventricular strain indices reached the minimum under a moderate exercise load (75 W), HR, SBP and CO were higher than those of the resting state ( P<0.05 or 0.01). Both LVEF under exercise loads of 75, 100, 125 W and during recovery, and SV under exercise loads of 100, 125 W and during recovery were significantly higher than those of the resting state ( P<0.05 or 0.01), while GLS and GCS under exercise loads of 50, 75, 125 W ( P<0.05 or 0.01), and GAS under exercise loads of 50, 75 W ( P<0.01) were significantly lower. There were statistically significant differences not only in GCS across the groups ( F=4.60, P=0.026) but also in DBP due to the interactions between the grouping and exercise loads ( F=3.13, P=0.031). DBP was higher than that of the resting state when the exercise load was 125 W in both groups. Conclusions:During submaximal exercise, myocardial contractility shows sustained enhancement with the increase of the exercise load. The results of GLS, GCS and GAS indicate that myocardial strain reaches its lowest value under a moderate exercise load, suggesting that moderate exercise can be used to evaluate cardiac function via 3D-SET. Under a simulated lunar gravity of 10° HUT, there is less deformation in the short axis direction of the myocardium, indicating that GCS can be used as a sensitive indicator to detect changes in cardiac function under different gravities.

Objective:To investigate the effects of 10° head up tilt bed rest (HUT) on human cardiac function via 3D speckle tracking echocardiography (3D-STE), and to study the difference in cardiac function under the submaximal exercise load between the horizontal position and 10° HUBR.Methods:Thirty young healthy volunteers were recruited as the subjects, who were randomly divided into an 10° HUT exercise group and horizontal exercise group with 15 subjects in each. Subjects in both groups were asked to ride the bicycle ergometer in the 10° HUBR position and supine position respectively. The load started with 50 W and was increased by 25 W every 3 min until it reached the maximum of 125 W. Before the exercise (resting state), 1 min after the load was increased each time, and 3 min after exercise (recovery period), the following indices were collected: ①basic cardiac function indices: heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP), ②conventional cardiac ultrasound indices: left ventricular ejection fraction (LVEF), stroke volume (SV) and cardiac output (CO), ③left ventricular strain indices: global longitudinal strain (GLS), global circumferential strain (GCS), and global area strain (GAS) measured by 3D-SET. The changes of these indices in the 2 groups of subjects under different exercise loads were observed.Results:The differences in the major effect of the basic heart indices (HR, SBP and DBP), conventional cardiac ultrasound indices (LVEF, SV and CO) and left ventricular strain indices (GLS, GCS and GAS) in response to the exercise load were statistically significant ( F=194.90, 113.66, 17.19, P=0.017, 0.018, 0.001). With the increase of the exercise load, the basic heart indices and conventional cardiac ultrasound indices kept rising, the left ventricular strain indices reached the minimum under a moderate exercise load (75 W), HR, SBP and CO were higher than those of the resting state ( P<0.05 or 0.01). Both LVEF under exercise loads of 75, 100, 125 W and during recovery, and SV under exercise loads of 100, 125 W and during recovery were significantly higher than those of the resting state ( P<0.05 or 0.01), while GLS and GCS under exercise loads of 50, 75, 125 W ( P<0.05 or 0.01), and GAS under exercise loads of 50, 75 W ( P<0.01) were significantly lower. There were statistically significant differences not only in GCS across the groups ( F=4.60, P=0.026) but also in DBP due to the interactions between the grouping and exercise loads ( F=3.13, P=0.031). DBP was higher than that of the resting state when the exercise load was 125 W in both groups. Conclusions:During submaximal exercise, myocardial contractility shows sustained enhancement with the increase of the exercise load. The results of GLS, GCS and GAS indicate that myocardial strain reaches its lowest value under a moderate exercise load, suggesting that moderate exercise can be used to evaluate cardiac function via 3D-SET. Under a simulated lunar gravity of 10° HUT, there is less deformation in the short axis direction of the myocardium, indicating that GCS can be used as a sensitive indicator to detect changes in cardiac function under different gravities.

Objective To compare the efficacies of unilateral biportal endoscopic(UBE)technique and percutaneous transforaminal endoscopic discectomy(PTED)in the treatment of lumbar spinal stenosis.Methods Forty patients who were diagnosed with lumbar spinal stenosis in Chashan Hospital of Dongguan from January 2019 to January 2023 were enrolled in this retrospective study.They were divided into PTED group(n=20)and UBE group(n=20).Perioperative data(operation time,intraoperative bleeding,postoperative hospital stay,degree of decompression and complications)were compared between the two groups.Visual analogue scale(VAS)score and Oswestry dysfunction index(ODI)were collected before surgery and on 3 days,1 month and 6 months after surgery.Results There were no significant differences in the operation time,intraoperative bleeding,or hospitalization time between the two groups(all P>0.05).The incidence of postoperative complications in the UBE group was significantly lower than that in the PTED group(P=0.001).VAS score and ODI of the low back and leg pains in the UBE group were superior to the PTED group at each postoperative time point(all P<0.05).One month after surgery,the UBE group had a more significant increase in the dural sac cross-sectional area and intervertebral foramen area than the PTED group(t=3.842,P=0.003;t=2.469,P=0.006).Conclusion Compared with PTED,UBE has better clinical outcomes,higher degree of decompression,and lower incidence of complications.UBE is a safe and feasible surgical method for the treatment of lumbar spinal stenosis.

Coronary restenosis is an important cause of poor long-term prognosis in patients with coronary heart disease. Here, we show that lysine methyltransferase SMYD2 expression in the nucleus is significantly elevated in serum- and PDGF-BB-induced vascular smooth muscle cells (VSMCs), and in tissues of carotid artery injury-induced neointimal hyperplasia. Smyd2 overexpression in VSMCs (Smyd2-vTg) facilitates, but treatment with its specific inhibitor LLY-507 or SMYD2 knockdown significantly inhibits VSMC phenotypic switching and carotid artery injury-induced neointima formation in mice. Transcriptome sequencing revealed that SMYD2 knockdown represses the expression of serum response factor (SRF) target genes and that SRF overexpression largely reverses the inhibitory effect of SMYD2 knockdown on VSMC proliferation. HDAC3 directly interacts with and deacetylates SRF, which enhances SRF transcriptional activity in VSMCs. Moreover, SMYD2 promotes HDAC3 expression via tri-methylation of H3K36 at its promoter. RGFP966, a specific inhibitor of HDAC3, not only counteracts the pro-proliferation effect of SMYD2 overexpression on VSMCs, but also inhibits carotid artery injury-induced neointima formation in mice. HDAC3 partially abolishes the inhibitory effect of SMYD2 knockdown on VSMC proliferation in a deacetylase activity-dependent manner. Our results reveal that the SMYD2-HDAC3-SRF axis constitutes a novel and critical epigenetic mechanism that regulates VSMC phenotypic switching and neointimal hyperplasia.

Objective To investigate the effect of patient's body shape and image acquisition mode on the radiation dose and image quality in percutaneous coronary angiography.Methods A total of 40 patients,who received selective percutaneous coronary angiography at the Ningbo Medical Center Lihuili Hospital of China between January 2022 and June 2023,were selected for this study.The patients were randomly divided into conventional group(including 11 males and 9 females,using coronary angiography mode to make image acquisition)and low-dose group(including 14 males and 6 females,using electrophysiological mode to make image acquisition).The patient's basic information,body size data,and the various radiation dose data were collected.The image quality rating scale for assessing the image quality was formulated.The independent sample t-test and Mann-Whitney U test were used for the comparison between the two groups.Pearson correlation analysis method was used to make correlation analysis.Results The larger the patient's chest circumference was,the higher the radiation dose would be,there was a positive linear relationship between the patient's chest circumference and the radiation dose.All the radiation dose parameters in the low-dose group were significantly lower than those in the conventional group(P＜0.01),and its reduction percentage was 48.51％-60.74％.No statistically significant difference in image quality score existed between the two groups(P＞0.0l),and in both groups the image quality was rated as good or better,meeting the requirements of intervention procedures.Conclusion In percutaneous coronary angiography the radiation dose is influenced by multiple factors including patient's body shape,image acquisition mode,exposure time,etc.Optimizing the image acquisition mode can remarkably reduce the radiation dose while maintaining the image quality and protecting the health of patients and operators.(J Intervent Radiol,2024,33:599-603)

Objective:To provide references for achieving long time continuous monitoring of cardiac functional changes of astronauts in spaceflight activities through continuously noninvasive assessment of left ventricular systolic function under exercise load by wearable cardiac sounds and ECG signals synchronization monitoring technology.Methods:Eleven healthy male youths were recruited for the study, and they did incremental load exercise on the recumbent power bicycle, starting at 50 W, increasing by 25 W every 3 minutes, until the maximum of 125 W reached. The subjects′ cardiac sounds and ECG signals at rest, 1 min after each level of load during exercise and 3 min after the end of exercise were selected; the transthoracic cardiac ultrasound examination of subjects was performed before and 5 min after exercise. The correlation between the cardiac sounds and ECG signals and left ventricular ejection fraction (LVEF) was analyzed, and a regression model was established to predict LVEF during exercise.Results:There were significant differences in heart rate, LVEF, electro-mechanical activation time (EMAT) and left ventricular ejection time (LVET) of subjects under different exercise loads ( F=53.22, 45.33, 3.65, 23.19, P<0.001, <0.001, =0.011, <0.001). Compared with the resting state, subjects showed increased heart rate and LVEF and a decreased EMAT and LVET during exercise loading, all of which were statistically significant ( P<0.01 or 0.05). In the correlation analysis, LVEF was negatively correlated with EMAT and LVEF ( r=-0.415, -0.758, P=0.002,<0.001), and positively correlated with the amplitude of the first heart sound ( r=0.606, P<0.001). The model for predicting LVEF was established by EMAT and LVET, and the multiple regression model was LVEF=108.698-0.092×LVET-0.134×EMAT ( r=0.87, P<0.001). Conclusions:The synchronous monitoring technology of cardiac sounds and ECG signals can continuously and non-invasively monitor LVEF changes during exercise. LVET is the most closely related to LVEF. LVEF is hopeful to predict the changes of cardiac function of astronauts in spaceflight activities.

Objective:To provide references for achieving long time continuous monitoring of cardiac functional changes of astronauts in spaceflight activities through continuously noninvasive assessment of left ventricular systolic function under exercise load by wearable cardiac sounds and ECG signals synchronization monitoring technology.Methods:Eleven healthy male youths were recruited for the study, and they did incremental load exercise on the recumbent power bicycle, starting at 50 W, increasing by 25 W every 3 minutes, until the maximum of 125 W reached. The subjects′ cardiac sounds and ECG signals at rest, 1 min after each level of load during exercise and 3 min after the end of exercise were selected; the transthoracic cardiac ultrasound examination of subjects was performed before and 5 min after exercise. The correlation between the cardiac sounds and ECG signals and left ventricular ejection fraction (LVEF) was analyzed, and a regression model was established to predict LVEF during exercise.Results:There were significant differences in heart rate, LVEF, electro-mechanical activation time (EMAT) and left ventricular ejection time (LVET) of subjects under different exercise loads ( F=53.22, 45.33, 3.65, 23.19, P<0.001, <0.001, =0.011, <0.001). Compared with the resting state, subjects showed increased heart rate and LVEF and a decreased EMAT and LVET during exercise loading, all of which were statistically significant ( P<0.01 or 0.05). In the correlation analysis, LVEF was negatively correlated with EMAT and LVEF ( r=-0.415, -0.758, P=0.002,<0.001), and positively correlated with the amplitude of the first heart sound ( r=0.606, P<0.001). The model for predicting LVEF was established by EMAT and LVET, and the multiple regression model was LVEF=108.698-0.092×LVET-0.134×EMAT ( r=0.87, P<0.001). Conclusions:The synchronous monitoring technology of cardiac sounds and ECG signals can continuously and non-invasively monitor LVEF changes during exercise. LVET is the most closely related to LVEF. LVEF is hopeful to predict the changes of cardiac function of astronauts in spaceflight activities.

Diagnosis and treatment of Hill-Sachs combined with Bankart lesions in anterior dislocation of shoulder joint is a major clinical challenge in orthopedics, because it likely leads to a high recurrence rate of redislocation of shoulder joint, a serious damage to the shoulder joint, recurrent shoulder injury and dramatically disturbed quality of daily life. Although various means of clinical diagnosis and treatment are available for the lesions, they all have their own advantages and disadvantages. However, arthroscopic surgery of shoulder has achieved superior curative effects, gradually becoming the first choice and a mainstream treatment. This article reviews the current research progress in pathogenesis, diagnosis and arthroscopic treatment of Hill-Sachs combined with Bankart lesions in anterior dislocation of shoulder joint.

OBJECTIVE: To assess the effect of miR-137 on the proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) induced by high glucose and its mechanism. METHODS: HUVECs cells were divided into low-glucose group (5.5 mmol/L glucose-treated cells), high-glucose group (33.36 mmol/L glucose-treated cells), anti-NC group (cells treated with 33.36 mmol/L glucose after anti-NC transfection) and anti-miR-137 group (cells treated with 33.36 mmol/L glucose after anti-miR-137 transfection). After 48 hours, qRT-PCR was used to determine the expression of miR-137. CCK-8 assay and flow cytometry were used to detect cell proliferation and apoptosis rate, respectively. The targeting relationship between miR-137 and AKT2 was validated by dual fluorescence reporter gene detection system and AKT2 protein expression after overexpression or inhibition of miR-137. RESULTS: High glucose could significantly up-regulate the expression of miR-137 in HUVECs cells, and the expression of miR-137 in HUVECs cells transfected with miR-137 inhibitor was significantly decreased (P<0.05). High glucose can significantly inhibit HUVECs cell proliferation and induce apoptosis, while inhibition of miR-137 expression can weaken the effect of high glucose on HUVECs cell proliferation inhibition and apoptosis promotion (P<0.05). Inhibiting AKT2 expression could weaken the inhibitory effect of miR-137 inhibitor on HUVECs cell proliferation and apoptosis (P<0.05). CONCLUSION Inhibiting the expression of miR-137 gene can attenuate the proliferation inhibition and apoptosis promotion of HUVECs induced by high glucose, and the mechanism is related to activating the expression of AKT2.
Apoptosis ; Cell Proliferation ; Cells, Cultured ; Glucose ; Human Umbilical Vein Endothelial Cells ; cytology ; Humans ; MicroRNAs ; genetics ; Proto-Oncogene Proteins c-akt ; genetics

Objective: To assess the effect of miR-137 on the proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs) induced by high glucose and its mechanism. Methods: HUVECs cells were divided into low-glucose group (5.5 mmol/L glucose-treated cells), high-glucose group (33.36 mmol/L glucose-treated cells), anti-NC group (cells treated with 33.36 mmol/L glucose after anti-NC transfection) and anti-miR-137 group (cells treated with 33.36 mmol/L glucose after anti-miR-137 transfection). After 48 hours, qRT-PCR was used to determine the expression of miR-137. CCK-8 assay and flow cytometry were used to detect cell proliferation and apoptosis rate, respectively. The targeting relationship between miR-137 and AKT2 was validated by dual fluorescence reporter gene detection system and AKT2 protein expression after overexpression or inhibition of miR-137. Results: High glucose could significantly up-regulate the expression of miR-137 in HUVECs cells, and the expression of miR-137 in HUVECs cells transfected with miR-137 inhibitor was significantly decreased (P<0.05). High glucose can significantly inhibit HUVECs cell proliferation and induce apoptosis, while inhibition of miR-137 expression can weaken the effect of high glucose on HUVECs cell proliferation inhibition and apoptosis promotion (P<0.05). Inhibiting AKT2 expression could weaken the inhibitory effect of miR-137 inhibitor on HUVECs cell proliferation and apoptosis (P<0.05). Conclusion Inhibiting the expression of miR-137 gene can attenuate the proliferation inhibition and apoptosis promotion of HUVECs induced by high glucose, and the mechanism is related to activating the expression of AKT2.