Objective:To investigate the effects of triptolide (TPL) and BET protein inhibitor JQ1 on proliferation inhibition and apoptosis induction of MLL-rearranged acute myeloid leukemia (AML) cell line MV4-11, and to explore their synergistic mechanisms.Methods:MV4-11 cells in logarithmic growth phase were treated with different concentrations (100, 200, 300, and 400 nmol/L) of JQ1, 4 nmol/L TPL or different concentrations of JQ1 combined with 4 nmol/L TPL for 48 h. Cell proliferation was detected by CCK-8 method, apoptosis was detected by flow cytometry (FCM), mitochondrial membrane potential was detected by JC-1 method, and expressions of mitochondrial apoptosis pathway-related proteins were detected by Western blot.Results:The 50% inhibitory concentration ( IC50) value of MV4-11 cells treated with JQ1 for 48 h was (283.9±10.7) nmol/L. However, 4 nmol/L TPL significantly enhanced the inhibitory effect of JQ1 on proliferation of MV4-11 cells, the IC50 value of MV4-11 cells treated with JQ1 combined with TPL was (148.1±2.6) nmol/L, and the difference was statistically significant ( t = 25.31, P = 0.029). The result of FCM assay showed that compared with the JQ1 alone group [(9.6±2.3)%, (12.6±1.4)%, (19.5±3.3)%, and (22.7±2.1)%], 4 nmol/L TPL combined with different concentrations (100, 200, 300, and 400 nmol/L) of JQ1 acted on MV4-11 cells for 48 h, the proportions of apoptotic cells were (16.4±1.9)%, (27.5±2.1)%, (32.9±3.6)%, and (35.5±3.0)%, respectively, the difference was statistically significant ( F = 9.25, P < 0.01). After treated with 4 nmol/L TPL and JQ1 for 12 h, the level of cell membrane potential in MV4-11 cells was significantly lower than that of JQ1 single agent group, and the difference was statistically significant ( P < 0.05). After treated by 4 nmol/L TPL combined with JQ1 for 24 h, the levels of anti-apoptotic proteins bcl-2 and Mcl-1 decreased, and the level of pro-apoptotic protein bax increased. Conclusion:TPL can significantly enhance the proliferation inhibition and apoptosis induction effects of BET protein inhibitor JQ1 on MLL-rearranged AML cells, and the mechanism may be related to enhancing the mitochondrial apoptosis pathway.

Objective:To evaluate the effectiveness and prognosis of emergent transcatheter aortic valve replacement (TAVR) and to provide standardized procedural suggestion for the development of emergent TAVR in China.Methods:From January 2020 to April 2021, 12 patients who underwent emergent or salvage TAVR in the Second Affiliated Hospital Zhejiang University School of Medicine were retrospectively enrolled from the TORCH registry (Transcatheter Aortic Valve Replacement Single Center Registry in Chinese Population, a prospective cohort study; NCT02803294). Baseline, periprocedural and 30-day follow up data were collected. Post-operative data were compared with pre-operative data using Paired-Samples test.Results:Patients’ median Society of Thoracic Surgeons score (STS score) was 15.432%. There was a significant decrease of mean gradient after emergent TAVR procedure (1.69 m/s vs. 4.90 m/s, P<0.01). During the 30-day follow up, there were 1 patient (8.3%) died and 2 patients received permanent pacemaker implantation. No disabling stroke, acute kidney injury, major vascular complication occurred during the first month after emergent TAVR. Among the survival patients, there was a significant releasing of heart failure symptoms to New York Heart Association function stage Ⅰ/Ⅱ in 81.8% patients at 30-day follow up. Left ventricular ejection fraction also improved significantly from (47.4±9.5)% to 58.8±8.0% ( P= 0.026). The mean gradient were (1.57±0.30) cm 2 and no patients had a moderate or severe paravalvular leakage. Besides, a significant decrease of pro-B-type natriuretic peptide (1 089.9 pg/mL vs. 12 215.5 pg/mL , P=0.001) and troponin T (0.020 ng/mL vs. 0.337 ng/mL, P=0.003) were found at 30 days after emergent TAVR. Conclusions:For patients with severe aortic stenosis and acute cardiac decompensated, emergent TAVR is a safe and effective rescue treatment.

Considering the surgical risk stratification for patients with severe calcific aortic stenosis (AS), transcatheter aortic valve replacement (TAVR) is a reliable alternative to surgical aortic valve replacement (SAVR) (Fan et al., 2020, 2021; Lee et al., 2021). Despite the favorable clinical benefits of TAVR, stroke remains a dreaded perioperative complication (Auffret et al., 2016; Kapadia et al., 2016; Kleiman et al., 2016; Huded et al., 2019). Ischemic overt stroke, identified in 1.4% to 4.3% of patients in TAVR clinical practice, has been associated with prolonged disability and increased mortality (Auffret et al., 2016; Kapadia et al., 2016; Levi et al., 2022). The prevalence of hyperintensity cerebral ischemic lesions detected by diffusion-weighted magnetic resonance imaging (DW-MRI) was reported to be about 80%, which is associated with impaired neurocognitive function and vascular dementia (Vermeer et al., 2003; Barber et al., 2008; Kahlert et al., 2010).
Humans ; Transcatheter Aortic Valve Replacement ; Aortic Valve Insufficiency ; Diffusion Magnetic Resonance Imaging ; Aortic Valve Stenosis ; Stroke