Objective:To explore the effects of mechanical ventilation（MV）at birth transition on lung pathophysiology and pathobiology in a very preterm animal model.Methods:Based on the model of respiratory distress syndrome（RDS）in very preterm rabbits at gestational age 26（term 31）days well established by the research group using perinatal medication and lung-protective ventilation strategies（very low tidal volume 1-3 mL/kg），we conducted a secondary data analysis. The studied rabbits were re-grouped according to the MV length（≤3 h，3-6 h，6-9 h，9-12 h，and >12 h）. The changes in lung mechanics，histopathology，phospholipid biochemistry，and mRNA relative expression of inflammatory/growth factor in lung tissue were evaluated over the time course of MV. The trend of each variable was tested by ANOVA trend test（ F trend）and Jonckheere-Terpstra trend test（ J-T value）with corresponding P value. Results:With the prolonged MV length，there was improved mean dynamic compliance of respiratory system（ F trend=16.722， P trend<0.001），along with decreased mean peak inspiratory pressure（ F trend =42.226， P trend<0.001）. The content of total phospholipids，disaturated phosphatidylcholine（ J-T=1 222，1 197， P trend=0.018，0.034，respectively）and total protein（ J-T=1 247 ，P trend= 0.009）in bronchoalveolar lavage fluid gradually increased. The wet lung weight in the ≤3 h group was significantly higher than in the other groups（ F=6.819， P<0.001）. The lung injury score（total，or hemorrhage，or inflammation）had progressive exacerbation in the ≤3 h，3-6 h and 6-9 h groups. The lung tissue mRNA expression of major proinflammatory cytokines increased modestly over the time groups in contrast to decreased expression of growth factors，of which the change of keratinocyte growth factor reached statistical significance（ J-T=531， P trend =0.034）. Conclusion:In the 26-day very preterm rabbits，with prolonged MV time，the content of surfactant phospholipid in the alveolar increased gradually，the lung compliance and lung fluid clearance gradually improved. Nevertheless，ventilator-induced lung injury remained evolving. The study warrants further study on the pathogenesis and protective strategies of early postnatal acute lung injury and chronic lung disease.

Objectives:To investigate the predictive value of the hemoglobin to serum creatinine ratio(Hb/SCr)for all-cause mortality within 3 years after percutaneous coronary intervention(PCI)in patients with ST-segment elevation myocardial infarction(STEMI).Methods:A total of 687 STEMI patients who successfully underwent the first PCI at the Department of Cardiology,Gansu Provincial People's Hospital,from June 2016 to June 2020 were retrospectively enrolled.Patients were divided into survival and non-survival groups according to their vital status at 3 years post-PCI.Cox regression analysis was performed to identify predictive factors of all-cause mortality.Receiver operating characteristic(ROC)curves were constructed to evaluate the predictive value of Hb/SCr for all-cause mortality,and Kaplan-Meier survival curves were used to compare cumulative survival rates between subgroups stratified by Hb/SCr levels.Results:The median follow-up duration was 37(25,50)months.Among the 663 patients(96.51%)with complete follow-up data,41 cases(6.18%)experiencing all-cause death.Multivariable Cox regression analysis revealed that age(HR=1.086,95%CI:1.037-1.137,P=0.000),body mass index(HR=1.195,95%CI:1.128-1.266,P=0.000),fasting blood glucose(HR=1.069,95%CI:1.007-1.135,P=0.030),fibrinogen(HR=1.418,95%CI:1.120-1.795,P=0.004),TIMI flow grade 1(HR=4.968,95%CI:1.194-20.667,P=0.028),TIMI flow grade 2(HR=3.861,95%CI:1.336-11.156,P=0.013),and Hb/SCr(HR=0.858,95%CI:0.766-0.961,P=0.008)were the independent predictors of all-cause mortality.ROC curve analysis demonstrated that the area under the curve(AUC)of Hb/SCr was 0.721(95%CI:0.645-0.798)for predicting all-cause mortality,with a sensitivity of 65.9%and specificity of 71.2%,at the optimal cut-offvalue of 16.627.Kaplan-Meier analysis showed that patients with Hb/SCr<16.627 had significantly lower survival rates than those with Hb/SCr≥16.627(log-rank P=0.000).Conclusions:Hb/SCr is an independent predictor of 3-year all-cause mortality in STEMI patients after PCI and this indicator could be used as risk stratification parameter and patients with lower Hb/SCr might benefit comprehensive post-PCI management to improve their outcome.

Objective:To explore the effects of mechanical ventilation（MV）at birth transition on lung pathophysiology and pathobiology in a very preterm animal model.Methods:Based on the model of respiratory distress syndrome（RDS）in very preterm rabbits at gestational age 26（term 31）days well established by the research group using perinatal medication and lung-protective ventilation strategies（very low tidal volume 1-3 mL/kg），we conducted a secondary data analysis. The studied rabbits were re-grouped according to the MV length（≤3 h，3-6 h，6-9 h，9-12 h，and >12 h）. The changes in lung mechanics，histopathology，phospholipid biochemistry，and mRNA relative expression of inflammatory/growth factor in lung tissue were evaluated over the time course of MV. The trend of each variable was tested by ANOVA trend test（ F trend）and Jonckheere-Terpstra trend test（ J-T value）with corresponding P value. Results:With the prolonged MV length，there was improved mean dynamic compliance of respiratory system（ F trend=16.722， P trend<0.001），along with decreased mean peak inspiratory pressure（ F trend =42.226， P trend<0.001）. The content of total phospholipids，disaturated phosphatidylcholine（ J-T=1 222，1 197， P trend=0.018，0.034，respectively）and total protein（ J-T=1 247 ，P trend= 0.009）in bronchoalveolar lavage fluid gradually increased. The wet lung weight in the ≤3 h group was significantly higher than in the other groups（ F=6.819， P<0.001）. The lung injury score（total，or hemorrhage，or inflammation）had progressive exacerbation in the ≤3 h，3-6 h and 6-9 h groups. The lung tissue mRNA expression of major proinflammatory cytokines increased modestly over the time groups in contrast to decreased expression of growth factors，of which the change of keratinocyte growth factor reached statistical significance（ J-T=531， P trend =0.034）. Conclusion:In the 26-day very preterm rabbits，with prolonged MV time，the content of surfactant phospholipid in the alveolar increased gradually，the lung compliance and lung fluid clearance gradually improved. Nevertheless，ventilator-induced lung injury remained evolving. The study warrants further study on the pathogenesis and protective strategies of early postnatal acute lung injury and chronic lung disease.

Objectives:To investigate the predictive value of the hemoglobin to serum creatinine ratio(Hb/SCr)for all-cause mortality within 3 years after percutaneous coronary intervention(PCI)in patients with ST-segment elevation myocardial infarction(STEMI).Methods:A total of 687 STEMI patients who successfully underwent the first PCI at the Department of Cardiology,Gansu Provincial People's Hospital,from June 2016 to June 2020 were retrospectively enrolled.Patients were divided into survival and non-survival groups according to their vital status at 3 years post-PCI.Cox regression analysis was performed to identify predictive factors of all-cause mortality.Receiver operating characteristic(ROC)curves were constructed to evaluate the predictive value of Hb/SCr for all-cause mortality,and Kaplan-Meier survival curves were used to compare cumulative survival rates between subgroups stratified by Hb/SCr levels.Results:The median follow-up duration was 37(25,50)months.Among the 663 patients(96.51%)with complete follow-up data,41 cases(6.18%)experiencing all-cause death.Multivariable Cox regression analysis revealed that age(HR=1.086,95%CI:1.037-1.137,P=0.000),body mass index(HR=1.195,95%CI:1.128-1.266,P=0.000),fasting blood glucose(HR=1.069,95%CI:1.007-1.135,P=0.030),fibrinogen(HR=1.418,95%CI:1.120-1.795,P=0.004),TIMI flow grade 1(HR=4.968,95%CI:1.194-20.667,P=0.028),TIMI flow grade 2(HR=3.861,95%CI:1.336-11.156,P=0.013),and Hb/SCr(HR=0.858,95%CI:0.766-0.961,P=0.008)were the independent predictors of all-cause mortality.ROC curve analysis demonstrated that the area under the curve(AUC)of Hb/SCr was 0.721(95%CI:0.645-0.798)for predicting all-cause mortality,with a sensitivity of 65.9%and specificity of 71.2%,at the optimal cut-offvalue of 16.627.Kaplan-Meier analysis showed that patients with Hb/SCr<16.627 had significantly lower survival rates than those with Hb/SCr≥16.627(log-rank P=0.000).Conclusions:Hb/SCr is an independent predictor of 3-year all-cause mortality in STEMI patients after PCI and this indicator could be used as risk stratification parameter and patients with lower Hb/SCr might benefit comprehensive post-PCI management to improve their outcome.

Objective:To evaluate the performance and application of a fast nucleic acid detection system for testing severe acute respiratory syndrome virus 2 (SARS-COV-2).Methods:Clinical samples were collected from February to July 2020 from Beijing Center for Diseases Prevention and Control and the Laboratory Department of China-Japan Friendship Hospital, to evaluate the sensitivity, specificity, anti-interference ability, precision and clinical sample coincidence rate of fast nucleic acid detection system for SARS-CoV-2. The analytical sensitivity was determined by a dilution series of 20 replications for each concentration. Analytical specificity study was performed by testing organisms whose infection produces symptoms similar to those observed at the onset of corona virus disease 2019 (COVID-19), and of the normal or pathogenic microflora that may be present in specimens collected. Potential interference substances were evaluated with different concentration in the interference study. Precision study was conducted by estimating intra-and inter-batch variability. Clinical evaluation was performed by testing 230 oropharyngeal swab specimens and 95 sputum specimens in fast nucleic acid detection system, comparing with conventional real-time fluorescent quantitative PCR (RT-qPCR) and clinical diagnostic results.Results:The analytical sensitivity of SARS-CoV-2 using fast nucleic acid detection system was 400 copies/ml. The result is negative for testing with the organisms that may likely in the circulating area or causing similar symptoms with SARS-CoV-2 and human nucleic acid, indicating that no cross reactivity with organisms. The results of precision test showed that the Coefficient of variation of Ct value of high, medium and low concentration samples was 1.90%-3.92%, and all of them were less than 5% in intra-and inter-batch testing. The results of the samples were still positive after adding the potential interfering substances, indicating that the possible interfering substances in the samples had no effect on the results. 98.46% and 97.85% diagnosis results of fast nucleic acid detection system were consistent with RT-qPCR and clinical diagnostic results, respectively.Conclusion:The fast nucleic acid detection system based on molecular parallel reaction can be used as a selection method for SARS-CoV-2 testing.

Objective:To explore the effect of aerobic exercise combined with diet management on volume overload and cardiac function in patients with peritoneal dialysis.Methods:A total of 100 patients who received peritoneal dialysis in the Second Affiliated Hospital of Xi ′an Jiaotong University from August 2017 to March 2019 were recruited in the present study. Patients were randomly divided into intervention group and control group according to the random number table (50 cases in each group). The control group received routine nursing, while the intervention group carried out aerobic exercise combined with diet management on the basis of routine nursing. Before and after 6 months of intervention, the volume status, edema degree and cardiac function were compared between the two groups. Results:After 6 months of intervention, the levels of body weight, 24 h urine volume, 24 h ultrafiltration volume, systolic pressure, extracellular water, and extracellular water/total body water were (58.99 ± 7.30) kg, (366.41 ± 66.92) ml, (565.08 ± 102.24) ml, (142.64 ± 11.70) mmHg (1 mmHg=0.133 kPa), (12.30 ± 2.01) L, 0.39 ± 0.08 in the intervention group, significantly lower than in the control group (63.46 ± 12.90) kg, (431.90 ± 78.92) ml, (625.35 ± 91.31) ml, (150.11 ± 11.44) mmHg, (14.37 ± 4.12) L, 0.43 ± 0.07, the differences were statistically significant ( t values were 2.026-4.208, all P<0.05); the left ventricular ejection fractions, E/A were (61.38 ± 9.42)%, 1.15 ± 0.35 in the intervention group, significantly higher than in the control group (57.04 ± 7.83)% and 1.00 ± 0.29, the differences were statistically significant ( t values were 2.358, 2.113, all P<0.05). After 6 months of intervention, the normal ratio increased and Ⅲ grade ratio decreased in the intervention group, the difference of edema degree between the two groups was statistically significant ( Z value was 3.153, P<0.01). Conclusions:Aerobic exercise combined with diet management can effectively control the volume overload status and improve the cardiac function of patients with peritoneal dialysis.

Objective:To investigate the relationship between the E2 and E4 alleles of apolipoprotein E (apoE) gene and myocardial infarction (MI) in type 2 diabetes Mellitus (T2DM) patients, and to explore the relationship between apoE polymorphism and blood lipid metabolism.Methods:This case control study was conducted from August 2016 to March 2020 in China-Japan Friendship Hospital, 3 459 inpatients with T2DM were included including 3 044 patients without MI (T2DM group) and 415 patients with MI (T2DM+MI group). Real time fluorescent quantitative PCR was used to detect apoE polymorphism. Automatic biochemical analyzer was used to detect lipid levels. Logistic regression analyses were performed to determine the association of apoE with risk of MI in patients with T2DM.Results:(1) The frequency of E4 allele in T2DM+MI group (12.29%, 102/830) was significantly higher than in T2DM group (9.13%,556/6 088), while the frequency of E2 allele in T2DM+MI group (7.35%,61/830) was significantly lower than that in T2DM group (8.21%,500/6 088), P=0.012. Logistic regression analyses showed that E4 allele carrier (E3/E4+E4/E4) faced a higher risk for MI in T2DM patients ( OR=1.48, 95% CI 1.14-1.92, P=0.003), while E2 allele carrier(E2/E3+E2/E2)did not face a higher risk of MI in T2DM patients ( OR=0.88, P=0.642). (2) The levels of apoE polymorphism and blood lipid: The levels of TC, LDL-C and apoB increased in the order of E4 allele, wild type and E2 allele ( P<0.05). The levels of HDL-C, apoA1 and apoE decreased in the order of E4 allele, Wild type and E2 allele ( P<0.05). Conclusion:The E4 allele is a risk factor for MI in T2DM patients, and apoE polymorphism can affect blood lipid level in this patent cohort.

Objective:To evaluate the performance and application of a fast nucleic acid detection system for testing severe acute respiratory syndrome virus 2 (SARS-COV-2).Methods:Clinical samples were collected from February to July 2020 from Beijing Center for Diseases Prevention and Control and the Laboratory Department of China-Japan Friendship Hospital, to evaluate the sensitivity, specificity, anti-interference ability, precision and clinical sample coincidence rate of fast nucleic acid detection system for SARS-CoV-2. The analytical sensitivity was determined by a dilution series of 20 replications for each concentration. Analytical specificity study was performed by testing organisms whose infection produces symptoms similar to those observed at the onset of corona virus disease 2019 (COVID-19), and of the normal or pathogenic microflora that may be present in specimens collected. Potential interference substances were evaluated with different concentration in the interference study. Precision study was conducted by estimating intra-and inter-batch variability. Clinical evaluation was performed by testing 230 oropharyngeal swab specimens and 95 sputum specimens in fast nucleic acid detection system, comparing with conventional real-time fluorescent quantitative PCR (RT-qPCR) and clinical diagnostic results.Results:The analytical sensitivity of SARS-CoV-2 using fast nucleic acid detection system was 400 copies/ml. The result is negative for testing with the organisms that may likely in the circulating area or causing similar symptoms with SARS-CoV-2 and human nucleic acid, indicating that no cross reactivity with organisms. The results of precision test showed that the Coefficient of variation of Ct value of high, medium and low concentration samples was 1.90%-3.92%, and all of them were less than 5% in intra-and inter-batch testing. The results of the samples were still positive after adding the potential interfering substances, indicating that the possible interfering substances in the samples had no effect on the results. 98.46% and 97.85% diagnosis results of fast nucleic acid detection system were consistent with RT-qPCR and clinical diagnostic results, respectively.Conclusion:The fast nucleic acid detection system based on molecular parallel reaction can be used as a selection method for SARS-CoV-2 testing.

Teaching rounds is an important part of clinical teaching practice, therefore, we established a demonstration team for teaching ward rounds. By formulating standard operation procedure for teaching rounds and encouraging innovation on teaching models, the team played a demonstration role in the clinical teaching rounds, which not only made up the shortcomings in teaching, but also improved the teaching level of clinical teachers and the quality of clinical training.

Objective To explore the value of transvaginal three-dimensional power Doppler ultrasound in evaluation of endometrial receptivity in patients with intrauterine adhesions.Methods Totally 43 patients with intrauterine adhesions confirmed by hysteroscopy were enrolled in this study.According to the hysteroscopy,the patients were divided into mild adhesion group (n=17),moderate adhesion group (n=18) and severe adhesion group (n=8).All the patients were examined with transvaginal three-dimensional power Doppler ultrasonography on the day of ovulation.Endometrial thickness (ED),endometrial volume (EV),endometrial vascular index (VI),endometrial flow index (FI) and endometrial vascular flow index (VFI) were compared among three groups.Results There was significant difference in EV among three groups (P＜0.001).ED,VI and VFI were significantly different between the mild and severe adhesion groups,as well as between moderate and severe adhesion groups (all P＜0.05).Conclusion Transvaginal three-dimensional power Doppler ultrasound provides a safe and noninvasive approach to assess endometrial receptivity of patients with intrauterine adhesions.EV has good predictive value on endometrial receptivity.