Objective To investigate the binding interaction between the calmodulin(CaM)mutant D130V and the IQ motif of the car-diac Cav1.2 channel.Methods The binding of mutant CaM-D130V to the IQ motif was predicted by fold recognition modeling,homology modeling,and protein docking.The plasmid was transformed into Escherichia coli BL-21 sensory cells via heat shock at 42 ℃ to induce the expression of glutathione S-transferase(GST)fusion protein.The protein was extracted by ultrasonic fragmentation and purified using GS-4B beads.PreScission protease was applied to remove the GST.SDS-PAGE was performed to detect the purity of protein.A GST pull-down assay was conducted to detect the interaction between CaM-D130V and IQ motif.Results Protein docking results showed that both CaM-WT and CaM-D130V could bind to the IQ motif of the cardiac Cav1.2 channel,but the binding sites of the mutant CaM-D130V to the IQ motif were reduced,and its binding conformation was changed compared with the CaM-WT,with decreased binding energy(|S|reduced from 48.086 6 kcal/mol to 47.309 5 kcal/mol).The GST pull-down assay indicated that the binding of CaM-D130V to IQ motif significantly decreased(P＜0.01),and the affinity was significantly reduced at 2 mmol/L Ca2+concentration compared with CaM-WT.Conclusion The reduced binding ability of CaM-D130V to the IQ motif of the cardiac Cav1.2 channel may contribute to functional alterations in the channel.These findings provide a theoretical basis for understanding the pathogenesis of CaM mutant-associated cardio-vascular diseases as well as targeted therapies.

Objective To investigate the binding interaction between the calmodulin(CaM)mutant D130V and the IQ motif of the car-diac Cav1.2 channel.Methods The binding of mutant CaM-D130V to the IQ motif was predicted by fold recognition modeling,homology modeling,and protein docking.The plasmid was transformed into Escherichia coli BL-21 sensory cells via heat shock at 42 ℃ to induce the expression of glutathione S-transferase(GST)fusion protein.The protein was extracted by ultrasonic fragmentation and purified using GS-4B beads.PreScission protease was applied to remove the GST.SDS-PAGE was performed to detect the purity of protein.A GST pull-down assay was conducted to detect the interaction between CaM-D130V and IQ motif.Results Protein docking results showed that both CaM-WT and CaM-D130V could bind to the IQ motif of the cardiac Cav1.2 channel,but the binding sites of the mutant CaM-D130V to the IQ motif were reduced,and its binding conformation was changed compared with the CaM-WT,with decreased binding energy(|S|reduced from 48.086 6 kcal/mol to 47.309 5 kcal/mol).The GST pull-down assay indicated that the binding of CaM-D130V to IQ motif significantly decreased(P＜0.01),and the affinity was significantly reduced at 2 mmol/L Ca2+concentration compared with CaM-WT.Conclusion The reduced binding ability of CaM-D130V to the IQ motif of the cardiac Cav1.2 channel may contribute to functional alterations in the channel.These findings provide a theoretical basis for understanding the pathogenesis of CaM mutant-associated cardio-vascular diseases as well as targeted therapies.

Objective:To investigate the effect of elevated low-density lipoprotein(LDL)cholesterol on the release of endothelial microvesicles into the circulatory system in elderly patients with obstructive sleep apnea(OSA).Methods:This was a case-control study.A total of 69 elderly inpatients aged ≥ 60 years were divided into the OSA group(n=48)and the normal control group(n=21)based on the apnea/hypopnea index(AHI). Sleep monitoring was carried out in the two groups, and venous blood samples were taken after the monitoring.Density gradient centrifugation was used to extract microparticles and flow cytometry was used to analyze patients' blood levels of endothelial microvesicles.Blood lipid levels of patients were measured by biochemical analysis methods.The correlation between LDL cholesterol levels and endothelial microvesicles in OSA patients was analyzed.Results:LDL cholesterol levels were higher in OSA patients than in normal controls(2.6±0.6 mmol/L vs.2.2±0.7 mmol/L, t=2.089, P=0.041). Endothelial microvesicle levels were elevated in OSA patients compared with the normal controls[(28.2±12.2)×10 -6events/L vs.(19.6±7.8)×10 -6 events/L, t=-3.164, P=0.003]. Endothelial microvesicle levels increased in OSA patients with elevated LDL cholesterol compared with OSA patients with normal LDL cholesterol[(39.3±12.6)×10 -6 events/L vs.(28.2±12.2)×10 -6 events/L, t=2.899, P=0.006]. There was a significant correlation between LDL cholesterol levels and endothelial microvesicle levels in OSA patients( r=0.497, P=0.032), while levels of HDL, total cholesterol, triglycerides, blood pressure and blood glucose had no significant correlation with endothelial microvesicle levels. Conclusions:The level of endothelial microvesicles released into the circulation is higher in elderly OSA patients than in normal elderly people, and the elevated concentration of LDL can further promote the release of endothelial microvesicles in OSA patients.

The outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 has rapidly spread globally. Cancer patients are at a higher risk of being infected with the coronavirus and are more likely to develop severe complications, as compared to the general population. The increasing spread of COVID-19 presents challenges for the clinical care of patients with gynecological malignancies. Concerted efforts should be put into managing gynecological malignancies in an orderly manner by strictly implementing the measures that are specifically developed for controlling the spread of COVID-19. We have drafted Recommendations on Management of Gynecological Malignancies during the COVID-19 Pandemic based on our experience on controlling COVID-19 pandemic in China. We recommend that patients with gynecological malignancies should be managed in hierarchical and individualized manners in combination with local conditions related to COVID-19. Medical care decision should be balanced between controlling COVID-19 pandemic spread and timely diagnosis and treatment for gynecologic oncology patients.

Objective To investigate the efficacy and safety of domestic bortezomibˉbased chemotherapy for patients with multiple myeloma (MM). Methods The clinical data of 60 MM patients treated with domestic bortezomibˉbased chemotherapy regimen (the observation group) in the First Affiliated Hospital of Zhengzhou University from April 2018 to October 2018 were retrospectively analyzed, which were compared with 112 MM patients treated with original treatment regimen (the control group) at the same hospital from November 2010 to November 2014. According to the disease stage, the patients were divided into newly diagnosed MM (NDMM) group and relapsed refractory MM (RRMM) group, and efficacy and adverse reactions of domestic bortezomib were evaluated. Results The total response rate (ORR) of the observation group was 71.7% (43/60), severe complete response (sCR) + complete response (CR) rate was 16.7% (10/60), very good partial response (VGPR) rate was 18.3% (11/60), and partial response (PR) rate was 36.7% (22/60). The ORR of NDMM group (45 cases) and RRMM group (15 cases) was 82.2% (37/45) and 40.0% (6/15), respectively, and the difference was statistically significant (χ2＝ 9.877, P < 0.05). There was no significant difference between ISS stage Ⅰ+Ⅱ and stage Ⅲ [ORR: 75.7% (28/37) vs. 65.2% (15/23), respectively; χ2＝0.764, P >0.05]. ORR and CR rates in the NDMM group and RRMM group of the observation group and the control group were not statistically different (all P>0.05). In the treatment of bortezomibˉbased chemotherapy, the common adverse reaction was peripheral neuropathy, mostly belonging to grade 1-2. Other side effects included hematocytopenia, gastrointestinal events and herpes zoster, which could be alleviated or restored to normality after supportive treatments. One patient died of pulmonary infection, respiratory failure and septic shock during the intermittent period of chemotherapy. Conclusion ORR of domestic bortezomibˉbased chemotherapy in treatment of the patients with MM is high, and the incidence of adverse reactions shows no significant increase compared with original drugs.