AIM: To optimize the extraction process for coumarins in Angelica Dahurica by supercritical CO 2 as guided by the contents of oxyimperatorin, imperatorin and the total coumarins in the extract. METHODS: HPLC was applied to determine the contents of oxyimperatorin and imperatorin. orthogonal design was applied to optimize SFE process. Range and variance analysis as well as stepwise nonlinear regression analysis were applied to deal with experimental results. RESULTS: The optimum process was established as following: 21MPa as extracting pressure, 50℃ as extracting temperature, 3.5h as extracting time, 20 mesh as pulverized degree and 6.5MPa as separating pressure. The relative error between experimental data and calculated value was less than 5%. CONCLUSION: Changes in extracting pressure, temperature, time, pulverized degree would affect the extracting results remarkably. Some factors had interactions on the extraction of coumarins in Angelica Dahurica . Regression equation was reasonable and could forecast results precisely.

Objective To explore the effects of H 2 S on neuronal injuries induced by oxygen glucose deprivation /reoxygenation ( OGD/R) in cortical neurons .Methods For OGD, the primary cultured cortical neurons were incubated with glucose-free EBSS media for 4h in N2/CO2/O2 (93%/5%/2%) atmosphere.Thereafter, the media were replaced by Neurobasal/B27 culture media and the neurons were incubated for 12 h in a 5%CO2 incubator at 37℃.NaHS was used as a H2S donor and cell survival rate was determined by cell counting kit 8(CCk-8).[Ca2+]i was determined using fura-2/AM and fluorescence microscopic imaging systems .The release rate of lactate dehydrogenase ( LDH) was determined by lactate dehydrogenase assay kit , and cell damage was analyzed by staining of propidium iodide ( PI ) .Results After pretreated with 200, 300 and 600μmol/L sodium hydrosulfide ( NaHS) for 30min before OGD/R, the cell survival rate of neurons significantly increased (n=4).[Ca2+]I(n=5), LDH release rate (n=4) and cell damage percentage (n=6) in the neuron pretreated with 300 μM NaHS were significantly lower than those in ODG/R cells.Treatment with 10μmol/L calcium chelator BAPTA also reduced the LDH release rate and cell damage percentage induced by ODG /R in neurons . Conclusion The results indicate that H 2 S may inhibit the OGD/R induced damage in cortical neurons via reducing calcium overload of neurons .

Taking into consideration the characteristics and current development status of air medical rescue,an analysis is conducted from the perspective of hospitals to examine the focal points and challenges in establishing the capability of hospital air medical rescue.A capability framework comprising five modules,namely planning system,service model,professional teams,hardware platform,and operational procedures,is proposed.The key tasks for each module are sorted out.Furthermore,the ex-ploration and practical experience of The First Affiliated Hospital of Sun Yat-sen University are shared,with the aim of providing a reference for the construction of hospital air medical rescue capabilities in the modern era.

Objective: To investigate the value of next-generation sequencing (NGS) technology in the prognosis monitoring and treatment guidance for molecular minimal residual disease (MRD) in acute myeloid leukemia (AML) patients with complete remission (CR). Methods: The clinical data of 68 AML (non-acute promyelocytic leukemia) patients who received gene mutation spectrum by using NGS technology at initial diagnosis and in CR phase in Tangdu Hospital of Air Force Military Medical University from January 2016 to July 2018 were retrospectively analyzed. The recurrence and survival of both molecular MRD positive group and negative group were analyzed and compared, and the value of NGS technology and multiparameter flow cytometry (MFC) were also analyzed in MRD monitoring. Results: There were 39 males (57.4%) and 29 females (42.6%) in 68 patients, and the median age was 52 years old (8-82 years old). Molecular MRD positive group included 38 patients, while negative group included 30 patients. Residual mutation gene type in CR phase was most frequently detected in epigenetic regulator gene mutations, such as ASXL1, TET2, DNMT3A and IDH1/IDH2. Statistical analysis showed that the 2-year cumulative recurrence rate (CIR) in the molecular MRD positive group was higher than that in the molecular MRD negative group (86.8% vs. 51.3%; χ² = 9.249, P = 0.002); the 2-year relapse-free survival (RFS) rate in the molecular MRD positive group was lower than that in the molecular MRD negative group (13.2% vs. 48.7%; χ² = 9.249, P = 0.002); the 2-year overall survival (OS) rate in the molecular MRD positive group was lower than that in the molecular MRD negative group (58.0% vs. 100%; χ² = 4.122, P = 0.042). Up to follow-up date, 3 patients with molecular MRD positive and 1 patient with molecular MRD negative who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) were still in disease-free survival. The results of monitoring MRD showed high consistency (76.7%, 33/43) in NGS and MFC. Compared with the other groups, the patients with both positive NGS and MFC had a higher relapse rate, and the difference was statistically significantly (P < 0.05). Conclusions Molecular MRD of AML patients is detected by using NGS technology, which could be used to predict the relapse and survival, suggesting that molecular MRD may guide post-remission treatment regimens and the determination of allo-HSCT indications.

Objective:To explore independent predictors for poor outcome at 3 months in elderly patients with acute cerebral infarction(ACI)treated with intravenous thrombolysis(IVT), and to develop a nomogram-based predictive model.Methods:This was a retrospective cohort study.Clinical, laboratory and imaging data of 346 elderly patients with ACI treated with IVT from January 2016 to April 2021 in our hospital were collected.Poor outcome was defined as a modified Rankin Scale(mRS)score >2 at 3 months after the stroke.Logistic regression analysis was used to screen for independent factors predicting poor outcome in elderly ACI patients treated with IVT, and a corresponding nomogram model was developed using the R software.The ROC curve, calibration plots and decision curve analysis were used to evaluate discrimination, calibration and clinical application value of the nomogram model.Results:Among 346 candidates, 109 developed a poor outcome, representing a rate of 31.5%.Logistic regression analysis showed that symptomatic hemorrhagic transformation( OR=15.647, 95% CI: 8.913-27.454), stroke severity(moderate stroke, OR=3.322, 95% CI: 1.414-7.811; moderate-severe stroke, OR=8.169, 95% CI: 4.102-16.258; severe stroke, OR=9.653, 95% CI: 5.440-17.121), stroke-associated pneumonia( OR=2.239, 95% CI: 1.134-4.420), and heart failure( OR=2.758, 95% CI: 1.424-5.336)were independent predictors for poor outcome at 3 months in elderly ACI patients treated with intravenous thrombolysis(all P<0.05). With the area under curve(AUC-ROC)value at 0.85(95% CI: 0.80-0.89), the nomogram model, which was composed of the above four predictors, demonstrated good discrimination.On the calibration plot, the mean absolute error was 0.020, indicating that the model had good calibration.Decision curve analysis revealed that the model had good clinical application value. Conclusions:The nomogram model composed of symptomatic hemorrhagic transformation, stroke severity, stroke-associated pneumonia and heart failure may predict poor outcome at 3 months in elderly ACI patients treated with IVT, with high prediction accuracy and high clinical application value.