BACKGROUND:It has been proved that induced pluripotent stem cells can differentiate into cardiomyocytes,but there are few reports on the maturity of differentiated cardiomyocytes.OBJECTIVE:To explore the effect of prolonging the induced differentiation time on the morphology,sarcomere length,binuclear cell content,cardiac gene expression,cardiac protein expression,and mitochondrial function of cardiomyocytes derived from induced pluripotent stem cells.METHODS:Bone morphogenetic protein 4,CH IR 99021,and IWR1 were used to induce pluripotent stem cells to differentiate into cardiomyocytes,and differentiated cardiomyocytes were collected on days 20 and 40 respectively.The expression levels of cardiac genes and proteins in differentiated cardiomyocytes were detected by RT-PCR and immunofluorescence,respectively.LAS X image analysis software was used to analyze the morphology and sarcomere length of differentiated cardiomyocytes.MitoTracker Green FM mitochondrial staining was used to detect total mitochondria.JC-1 mitochondrial staining was used to detect mitochondrial membrane potential.RESULTS AND CONCLUSION:Differentiated card io myocytes on day 40 had longer cell circumference and sarcomere length,and larger cell area than those on day 20(P＜0.05).The proportion of multinucleated cells rose sharply from about 16％on day 20 to about 29％on day 40(P＜0.05).Differentiated cardiomyocytes on day 40 had gene expression levels that were more similar to those of the primary cardiomyocytes,and the expression levels of SERCA2A,Cx-43,and α-MHC genes were significantly higher than on day 20(P＜0.05).Compared with the differentiated cardiomyocytes on day 20,the expression density of TNNT2 and α-MHC protein was relatively higher,the distribution density of mitochondria was larger,and the number of functional mitochondria was greater on day 40(P＜0.05).The results show that prolonging the induced differentiation time can increase the maturity of differentiated cardiomyocytes by increasing the length of sarcomere and the number of functional mitochondria,as well as improving the expression levels of cardiac genes and proteins.

Extensive epigenetic reprogramming involves in memory CD8+ T-cell differentiation. The elaborate epigenetic rewiring underlying the heterogeneous functional states of CD8+ T cells remains hidden. Here, we profile single-cell chromatin accessibility and map enhancer-promoter interactomes to characterize the differentiation trajectory of memory CD8+ T cells. We reveal that under distinct epigenetic regulations, the early activated CD8+ T cells divergently originated for short-lived effector and memory precursor effector cells. We also uncover a defined epigenetic rewiring leading to the conversion from effector memory to central memory cells during memory formation. Additionally, we illustrate chromatin regulatory mechanisms underlying long-lasting versus transient transcription regulation during memory differentiation. Finally, we confirm the essential roles of Sox4 and Nrf2 in developing memory precursor effector and effector memory cells, respectively, and validate cell state-specific enhancers in regulating Il7r using CRISPR-Cas9. Our data pave the way for understanding the mechanism underlying epigenetic memory formation in CD8+ T-cell differentiation.
CD8-Positive T-Lymphocytes/metabolism* ; Cell Differentiation ; Chromatin/immunology* ; Animals ; Mice ; Immunologic Memory ; Epigenesis, Genetic ; SOXC Transcription Factors/immunology* ; NF-E2-Related Factor 2/immunology* ; Mice, Inbred C57BL ; Gene Regulatory Networks ; Enhancer Elements, Genetic

Objective To investigate the feasibility of parallel capillary bundle arrays for physiomimetic impedance modeling and establish a parametric quantification framework,thereby providing a customizable impedance characterization methodology for diverse in-vitro mock circulation researches.Methods Based on the parallel flow resistance and Poiseuille equation,a tube resistance element with multiple parallel-aligned capillary glass tubes was designed and fabricated.The resistance values of the capillary-bundle and a ball valve were measured through constant flow experiments analogous to electrical resistance measurement method.Moreover,a simple lumped-parameter mock circulation loop was constructed and the pressure and flow rate for each node of the loop were measured under different input flow waveforms.An 0D-Windkessel model corresponding to the experiment was developed.The impedance and compliance were adjusted to match the simulated and experimental pressure and flow waveforms.The accuracy of the capillary bundle impedance in pulsatile experiments was verified by using the computational resistance values.Results The constant-flow impedance calibration experiments revealed that the capillary bundle impedance remained unaffected by flow rate variations over a wide flow range.When the capillary bundle impedance was integrated into the pulsatile circulatory system and the same impedance value obtained from the constant-flow calibration was applied in the computational model,the resulting pressure and flow waveforms showed good agreement with those measured in the pulsatile experiments.However,when the ball valves with nominally identical impedance values were inserted in the pulsatile system,the calculated impedance exhibited a two-fold difference,and significant discrepancies were observed between the simulated and experimental terminal flow waveforms.Conclusions The capillary bundle impedance maintains a constant value regardless of flow rate variations.Once the calibrated resistance value is determined through constant flow experiments,it can be directly applied to pulsatile systems.This approach can provide quantitative pulsatile flow conditions for testing various medical devices.

Objective To investigate the feasibility of parallel capillary bundle arrays for physiomimetic impedance modeling and establish a parametric quantification framework,thereby providing a customizable impedance characterization methodology for diverse in-vitro mock circulation researches.Methods Based on the parallel flow resistance and Poiseuille equation,a tube resistance element with multiple parallel-aligned capillary glass tubes was designed and fabricated.The resistance values of the capillary-bundle and a ball valve were measured through constant flow experiments analogous to electrical resistance measurement method.Moreover,a simple lumped-parameter mock circulation loop was constructed and the pressure and flow rate for each node of the loop were measured under different input flow waveforms.An 0D-Windkessel model corresponding to the experiment was developed.The impedance and compliance were adjusted to match the simulated and experimental pressure and flow waveforms.The accuracy of the capillary bundle impedance in pulsatile experiments was verified by using the computational resistance values.Results The constant-flow impedance calibration experiments revealed that the capillary bundle impedance remained unaffected by flow rate variations over a wide flow range.When the capillary bundle impedance was integrated into the pulsatile circulatory system and the same impedance value obtained from the constant-flow calibration was applied in the computational model,the resulting pressure and flow waveforms showed good agreement with those measured in the pulsatile experiments.However,when the ball valves with nominally identical impedance values were inserted in the pulsatile system,the calculated impedance exhibited a two-fold difference,and significant discrepancies were observed between the simulated and experimental terminal flow waveforms.Conclusions The capillary bundle impedance maintains a constant value regardless of flow rate variations.Once the calibrated resistance value is determined through constant flow experiments,it can be directly applied to pulsatile systems.This approach can provide quantitative pulsatile flow conditions for testing various medical devices.

BACKGROUND:It has been proved that induced pluripotent stem cells can differentiate into cardiomyocytes,but there are few reports on the maturity of differentiated cardiomyocytes.OBJECTIVE:To explore the effect of prolonging the induced differentiation time on the morphology,sarcomere length,binuclear cell content,cardiac gene expression,cardiac protein expression,and mitochondrial function of cardiomyocytes derived from induced pluripotent stem cells.METHODS:Bone morphogenetic protein 4,CH IR 99021,and IWR1 were used to induce pluripotent stem cells to differentiate into cardiomyocytes,and differentiated cardiomyocytes were collected on days 20 and 40 respectively.The expression levels of cardiac genes and proteins in differentiated cardiomyocytes were detected by RT-PCR and immunofluorescence,respectively.LAS X image analysis software was used to analyze the morphology and sarcomere length of differentiated cardiomyocytes.MitoTracker Green FM mitochondrial staining was used to detect total mitochondria.JC-1 mitochondrial staining was used to detect mitochondrial membrane potential.RESULTS AND CONCLUSION:Differentiated card io myocytes on day 40 had longer cell circumference and sarcomere length,and larger cell area than those on day 20(P＜0.05).The proportion of multinucleated cells rose sharply from about 16％on day 20 to about 29％on day 40(P＜0.05).Differentiated cardiomyocytes on day 40 had gene expression levels that were more similar to those of the primary cardiomyocytes,and the expression levels of SERCA2A,Cx-43,and α-MHC genes were significantly higher than on day 20(P＜0.05).Compared with the differentiated cardiomyocytes on day 20,the expression density of TNNT2 and α-MHC protein was relatively higher,the distribution density of mitochondria was larger,and the number of functional mitochondria was greater on day 40(P＜0.05).The results show that prolonging the induced differentiation time can increase the maturity of differentiated cardiomyocytes by increasing the length of sarcomere and the number of functional mitochondria,as well as improving the expression levels of cardiac genes and proteins.

Objective Chlorination is often used to disinfect recreational water in large amusement parks;however,the health hazards of chlorination disinfection by-products(DBPs)to occupational populations are unknown.This study aimed to assess the exposure status of chlorinated DBPs in recreational water and the health risks to employees of large amusement parks. Methods Exposure parameters of employees of three large amusement parks in Shanghai were investigated using a questionnaire.Seven typical chlorinated DBPs in recreational water and spray samples were quantified by gas chromatography,and the health risks to amusement park employees exposed to chlorinated DBPs were evaluated according to the WHO's risk assessment framework. Results Trichloroacetic acid,dibromochloromethane,bromodichloromethane,and dichloroacetic acid were detected predominantly in recreational water.The carcinogenic and non-carcinogenic risks of the five DBPs did not exceed the risk thresholds.In addition,the carcinogenic and non-carcinogenic risks of mixed exposure to DBPs were within the acceptable risk limits. Conclusion Typical DBPs were widely detected in recreational water collected from three large amusement parks in Shanghai;however,the health risks of DBPs and their mixtures were within acceptable limits.

Purpose To assess the right atrial and right ventricular strain and right ventricular-pulmonary artery(RV-PA)coupling in rheumatoid arthritis(RA)via two-dimensional speckle tracking.Materials and Methods Sixty patients with RA in the General Hospital of Ningxia Medical University from June 2020 to June 2022 were prospectively selected,and all RA patients were divided into three groups according to pulmonary artery systolic pressure(PASP),including group A(n=20 cases)with PASP<33 mmHg,group B(n=20 cases)with PASP 33-39 mmHg as mild ePH,and group C(n=20 cases)PASP≥40 mmHg,twenty healthy individuals were selected as the control group.All subjects underwent transthoracic echocardiography,and right atrial and right ventricular systolic function was assessed by two-dimensional speckle tracking technique,and RV-PA coupling was assessed noninvasively by right ventricular free wall strain/pulmonary artery systolic pressure(RV FWS/PASP),pulmonary function was analyzed by pulmonary function instruments.Spearman's analysis was used to analyze the correlation between right heart function and RV-PA coupling to pulmonary diffusion function.Results There were statistical differences in right ventricular base diameter,right atrium diameter,tricuspid annular plane systolic excursion,inferior vena cava diameter,PASP,right ventricular global strain,RV FWS,right atrium strain-reservoi,right atrium strain-conduit(S-CD),RV FWS/PASP among the four groups(F/H=2.369-74.880,all P<0.05).Right atrium strain-reservoi[(36.0±7.9)%vs.(30.9±7.8)%],right atrium S-CD[(19.9±6.9)%vs.(15.3±4.7)%]and RV FWS/PASP(0.96±0.19 vs.0.56±0.13)in group B were significantly lower than those of group A(t=2.040,2.262,7.704,all P<0.05).There was a good correlation between diffusing capacity of the lung for carbon monoxide single-breathmethod and right ventricular global strain,RV FWS,right atrium S-CD and RV FWS/PASP in RA patients(r=0.392,0.472,0.431,0.572,all P<0.05).Conclusion The more increases of pulmonary artery pressures,the more decreases of right heart function in RA patients,and the more uncoupling in RV-PA.Right heart dysfunction and right ventricle-pulmonary artery uncoupling have developed in RA patients with PASP 33-39 mmHg,with association of pulmonary diffusion dysfunction.

Purpose: Patients with advanced biliary tract cancer (BTC) have a poor survival. We aim to evaluate the efficacy and safety of nab-paclitaxel plus gemcitabine and cisplatin regimen in Chinese advanced BTC patients. Materials and Methods: Eligible patients with locally advanced or metastatic BTC administrated intravenous 100 mg/m2 nab-paclitaxel, 800 mg/m2 gemcitabine, and 25 mg/m2 cisplatin every 3 weeks. The primary endpoint was progression-free survival (PFS). The secondary endpoints included overall survival (OS) and adverse events, while exploratory endpoint was the association of biomarkers with efficacy. Results: After the median follow-up of 25.0 months, the median PFS and OS of 34 enrolled patients were 7.1 months (95% confidence interval [CI], 5.4 to 13.7) and 16.4 months (95% CI, 10.9 to 23.6), respectively. The most common treatment-related adverse events at ≥ 3 grade were neutropenia (26.5%) and leukopenia (26.5%). Survival analyses demonstrated that carcinoembryonic antigen (CEA) levels could monitor patients’ survival outcomes. A significant increase in the number of infiltrating CD4+ cells (p=0.008) and a decrease in programmed death-1–positive (PD-1+) cells (p=0.032) were observed in the response patients. Conclusion In advanced BTC patients, nab-paclitaxel plus gemcitabine and cisplatin regimen showed therapeutic potential. Potential prognostic factors of CEA levels, number of CD4+ cells and PD-1+ cells may help us maximize the efficacy benefit.

Objective:The study aimed to assess the scientific rigor, transparency, and practicality of Chinese geriatric medicine guidelines and consensus published in academic journals.Methods:A systematic search was conducted across 8 major Chinese and English databases to identify guidelines and consensus documents from Chinese scholars in 2022.Results:The selected documents were evaluated using the STAR rating tool, resulting in the inclusion of 2 guidelines and 19 expert consensuses.The total scores ranged from 9.0 to 50.6 points, with an average score of 29.6±13.1 points.The highest score rate in the'Consensus Methods’category of expert consensuses was 47.4%, while the lowest score rate in the'Registration’category was 0.For guidelines, the highest score rate in the'Consensus Methods’category was 42.9%, while the lowest score rates were observed in the'Registration’, 'Plan’, and'Others’categories at 0.Conclusions:The overall quality of geriatric medicine guidelines and consensus in China requires enhancement.There is a need to improve training in guideline consensus development, involve methodologists, elevate the standards for journal publication, and strive to enhance the scientific rigor, transparency, and practicality of guidelines and consensus documents.

Objective:To investigate the correlation between serum vitamin D and the risk of pre-eclampsia at the early, middle and late stages of pregnancy.Methods:Pregnant women who registered and delivered in Electric Power Teaching Hospital of Capital Medical University from August 2020 to July 2021 were included. Pregnant women with pre-eclampsia during pregnancy were selected as the case group (150 cases), while pregnant women without any complications after delivery were selected as the control group (600 cases) according to the 1∶4 matching principle (age, pre-pregnancy body mass index and last menstruation). The levels of serum vitamin D in differences stages of pregnancy between the two groups were compared. Logistic regression model was used to analyze the association between serum vitamin D levels and the risk of pre-eclampsia.Results:The levels of serum vitamin D at the early, middle and late stages of pregnancy in the case group were lower than those in the control group: (14.32 ± 3.61) μg/L vs. (18.78 ± 4.73) μg/L, (15.06 ± 3.12) μg/L vs. (19.88 ± 4.25) μg/L, (16.04 ± 3.51) μg/L vs. (22.04 ± 5.63) μg/L, there were statistical differences ( P<0.05). Taking pregnant women with adequate serum Vitamin D as a reference, and adjusting for confounding factors such as gain weight and primipara, the risk of pre-eclampsia in early stages pregnant women with serum Vitamin D serious deficiency, middle deficiency and deficiency was increased and the OR and 95% CI were 4.84(1.25 -31.42), 3.09(1.12 - 8.96), 1.48(1.12 - 13.05); the risk of pre-eclampsia in middle stages pregnant women with serum vitamin D serious deficiency, middle deficiency and deficiency was increased and the OR(95% CI) were 4.43(1.23 - 13.55), 2.22(1.05 - 6.78), 1.12(0.45 - 7.73); the risk of pre-eclampsia in late stages pregnant women with serum vitamin D serious deficiency, middle deficiency and deficiency was increased and the OR(95% CI) were 2.13(1.12 - 8.64), 1.76(1.02 - 4.98), 1.22(0.72 - 3.94). Conclusions:The level of serum vitamin D is associated with the risk of pre-eclampsia in pregnant women in the early, middle and late stages of pregnancy, and the risk of pre-eclampsia is significantly increase when the level of serum vitamin D is severely deficient or deficient during pregnancy.