Objective　To conduct a genotypic analysis of dengue virus in Gengma County, Yunnan Province, located in the China-Myanmar border region in 2023, and provide a reference for developing effective clinical diagnosis and treatment strategies for dengue fever in the region. Methods Serum samples were collected from hospitalized patients testing positive for dengue NS1 antigen, and dengue virus nucleic acid was detected using real-time quantitative PCR (qPCR). Nucleic acid-positive samples underwent cell culture and sequencing analysis of the dengue virus E gene to determine the origin of the virus. Results Specific nucleic acid detection was performed in 86 NS1-positive serum samples, 75 samples tested positive for dengue virus serotype 1 (DENV-1), 6 samples for serotype 2 (DENV-2), and 5 samples were DENV-negative. Twelve DENV-1 and four DENV-2 strains were obtained by blind cell culture transmission for 3 generations. Sequencing of E gene sequences (1 485 bp) of 16 strains showed that the nucleotide similarity of 12 DENV-1 E gene sequences ranged from 99.3% to 100.0%, with amino acid homology of 99.8% to 100.0%. For the 4 DENV-2 E gene sequences, the nucleotide similarity ranged from 99.7% to 99.9%, and amino acid homology ranged from 99.0% to 99.8%. Phylogenetic analysis showed that 12 DENV-1 strains belonged to genotype I, while 4 DENV-2 strains belonged to the Asian-II genotype. Conclusion The dengue fever outbreak in Gengma County, Yunnan Province, China, the China-Myanmar border area, was mainly caused by dengue virus 1 genotype I and dengue virus 2 genotype Asian-II. Both dengue virus 1 and 2 may have similar original strains from Guangzhou, China in 2023. It was recommended that local relative departments should strengthen the monitoring of dengue fever.

Objective To analyze the risk factors and re-intervention strategies for mid- and long-term residual after arterial switch operation (ASO). Methods The clinical data of children with complex congenital heart disease who underwent ASO surgery in Shanghai Children’s Medical Center from January 2006 to June 2022 were retrospectively collected, and the risk factors for mid- and long-term residual after ASO were analyzed. Results A total of 952 children undergoing ASO were enrolled in this study, including 654 males and 298 females with an average age of (102.9±90.1) d and weight of (4.6±1.6) kg. There were 421 patients with D-transposition of the great arteries with intact ventricular septum (D-TGA/IVS), 357 patients with D-transposition of the great arteries with ventricular septal defect (D-TGA/VSD), and 174 patients with right ventricle double outlet combined with subpulmonary ventricular septal defect (Taussig-Bing malformation). Eighty-nine patients died early after the surgery, the mortality rate was 9.3%. The 746 surviving children were regularly followed up after the surgery (follow-up rate 86.4%), with a median follow-up time of 79.4 (12.0-188.0) months. During the follow-up, 53 children underwent surgical re-intervention due to residual, including 33 males and 20 females, with a median age of 62.5 (17.0-214.0) months. The median surgical weight was 19.0 (8.2-86.0) kg, and the mean time of re-intervention was 28.0-170.0 (77.5±45.4) months after the ASO. Residual problems included common trunk and branch stenosis of the pulmonary artery in 23 patients, right ventricular outflow tract (RVOT) obstruction in 11 patients, left ventricular outflow tract obstruction in 6 patients, aortic arch restenosis in 5 patients, aortic insufficiency in 5 patients, residual shunt of ventricular septal defect in 2 patients, and tricuspid valve insufficiency in 1 patient. The early postoperative mortality rate was 3.8% (2/53), with the causes of death being acute myocardial infarction due to coronary artery injury and acute left heart failure, respectively. The mean follow-up time of the surviving children was (52.4±28.6) months, and no mid- and long-term death occurred. Two patients underwent the third operations due to pulmonary restenosis. The multivariate analysis result showed that combined aortic arch surgery and early postoperative RVOT velocity>3 m/s were independent risk factors for mid- and long-term residual after ASO. Conclusion ASO is an ideal procedure for the treatment of D-TGA/IVS, D-TGA/VSD and Taussig-Bing malformations. Combined aortic arch surgery and early postoperative RVOT velocity>3 m/s are independent risk factors for mid- and long-term residual after ASO.

L-citrulline is a nonprotein amino acid that plays an important role in human health and has great market demand. Although microbial cell factories have been widely used for biosynthesis, there are still challenges such as genetic instability and low efficiency in the biosynthesis of L-citrulline. In this study, an efficient, plasmid-free, non-inducible L-citrulline-producing strain of Escherichia coli BL21(DE3) was engineered by combined strategies. Firstly, a chassis strain capable of synthesizing L-citrulline was constructed by block of L-citrulline degradation and removal of feedback inhibition, with the L-citrulline titer of 0.43 g/L. Secondly, a push-pull-restrain strategy was employed to enhance the L-citrulline biosynthesis, which realized the L-citrulline titer of 6.0 g/L. Thirdly, the NADPH synthesis and L-citrulline transport were strengthened to promote the synthesis efficiency, which achieved the L-citrulline titer of 11.6 g/L. Finally, fed-batch fermentation was performed with the engineered strain in a 3 L fermenter, in which the L-citrulline titer reached 44.9 g/L. This study lays the foundation for the industrial production of L-citrulline and provides insights for the modification of other amino acid metabolic networks.
Citrulline/biosynthesis* ; Escherichia coli/genetics* ; Metabolic Engineering/methods* ; Fermentation ; NADP/biosynthesis*

Objective:To evaluate the efficacy and safety of nebulized inhalation of recombinant human interferon (IFN) α1b injection in the treatment of respiratory syncytial virus (RSV) associated lower respiratory tract infections (pneumonia and bronchiolitis) in children.Methods:A randomized, double-blind, parallel, placebo-controlled add-on design was used.Children with pneumonia or bronchiolitis aged 2 months to 5 years who tested positive for RSV antigen within 72 hours of onset from 30 clinical trial sites including Beijing Children′s Hospital, Capital Medical University between February 2021 and December 2022 were included in this study and randomly divided into 2 groups at a ratio of 1∶1 based on a stratified-block method.Both groups received basic treatments such as cough control, asthma relieving, expectorant treatment, fever reduction, oxygen therapy, etc.The experimental group received additional nebulized inhalation of IFN α1b injection at a dose of 2.0 μg/(kg·time), twice a day.The control group received nebulized inhalation of placebo twice a day.Clinical efficacy was evaluated based on indicators such as the duration of clinical symptoms and signs, and the Kaplan-Meier method was used to calculate the median and 95% CI of the duration of clinical symptoms and signs.The Log-rank test was used to compared data between groups.Safety was assessed through the incidence of adverse reactions and laboratory tests, and the Chi-square test was used to analyze the difference between groups. Results:There were 123 children in the experimental group and 122 children in the control group.The median durations of all the 5 clinical symptoms and signs [including shortness of breath, wheezing, dyspnea (visible retractions), decreased transcutaneous oxygen saturation, and abnormal mental state] in the experimental group after treatment were slightly shortened than those in the control group [2.7 d(95% CI: 1.9-3.0 d)] vs.[2.9 d(95% CI: 2.6-3.6 d), P=0.027].The improvement in dyspnea (retractions) was especially pronounced in the experimental group, with a relief rate of 50.0% (0, 100%) on the first day of administration[compared with 0 (0, 50.0%) in the control group ( Z=2.002, P=0.025)].The median duration of dyspnea in the experimental group was nearly 1 day shorter than that in the control group [1.0 d(95% CI: 0.7-1.7 d) vs.1.8 d(95% CI: 1.0-2.5 d), P=0.046].There were no significant difference in hospital stay [6.0(5.0, 8.0) d vs.6.5(5.0, 8.0) d, Z=0.675, P=0.500], oxygen therapy duration [32.0(14.0, 96.3) h vs.39.0 (24.0, 83.2) h, Z=0.094, P=0.925], the recovery rate from clinical symptoms during treatment [(105/106, 99.1%) vs.(96/101, 95.0%)], and recurrence rate [(0/106, 0) vs.(2/101, 2.0%)] between the 2 groups (all P>0.05).However, the above-mentioned four indicators in the experimental group showed a trend of clinical benefits.The quantitative virus detection results showed that the RSV viral load in both groups decreased after treatment compared to before treatment.After 2 days of treatment, the decline rate of RSV viral load from the baseline was 0.90 lg copies/(mL·d) in the experimental group and 0.25 lg copies/(mL·d)in the control group, with a statistically significant difference ( P<0.05).Furthermore, there was no statistically significant difference in the incidence of adverse reactions between the 2 groups ( P>0.05).Importantly, no drug-related serious adverse reactions occurred in both groups. Conclusions:The nebulized inhalation therapy of IFN α1b demonstrates efficacy and safety in treating pediatric RSV associated lower respiratory tract infections.It particularly offers outstanding clinical therapeutic value for severe children.

Objective:To evaluate the efficacy and safety of nebulized inhalation of recombinant human interferon (IFN) α1b injection in the treatment of respiratory syncytial virus (RSV) associated lower respiratory tract infections (pneumonia and bronchiolitis) in children.Methods:A randomized, double-blind, parallel, placebo-controlled add-on design was used.Children with pneumonia or bronchiolitis aged 2 months to 5 years who tested positive for RSV antigen within 72 hours of onset from 30 clinical trial sites including Beijing Children′s Hospital, Capital Medical University between February 2021 and December 2022 were included in this study and randomly divided into 2 groups at a ratio of 1∶1 based on a stratified-block method.Both groups received basic treatments such as cough control, asthma relieving, expectorant treatment, fever reduction, oxygen therapy, etc.The experimental group received additional nebulized inhalation of IFN α1b injection at a dose of 2.0 μg/(kg·time), twice a day.The control group received nebulized inhalation of placebo twice a day.Clinical efficacy was evaluated based on indicators such as the duration of clinical symptoms and signs, and the Kaplan-Meier method was used to calculate the median and 95% CI of the duration of clinical symptoms and signs.The Log-rank test was used to compared data between groups.Safety was assessed through the incidence of adverse reactions and laboratory tests, and the Chi-square test was used to analyze the difference between groups. Results:There were 123 children in the experimental group and 122 children in the control group.The median durations of all the 5 clinical symptoms and signs [including shortness of breath, wheezing, dyspnea (visible retractions), decreased transcutaneous oxygen saturation, and abnormal mental state] in the experimental group after treatment were slightly shortened than those in the control group [2.7 d(95% CI: 1.9-3.0 d)] vs.[2.9 d(95% CI: 2.6-3.6 d), P=0.027].The improvement in dyspnea (retractions) was especially pronounced in the experimental group, with a relief rate of 50.0% (0, 100%) on the first day of administration[compared with 0 (0, 50.0%) in the control group ( Z=2.002, P=0.025)].The median duration of dyspnea in the experimental group was nearly 1 day shorter than that in the control group [1.0 d(95% CI: 0.7-1.7 d) vs.1.8 d(95% CI: 1.0-2.5 d), P=0.046].There were no significant difference in hospital stay [6.0(5.0, 8.0) d vs.6.5(5.0, 8.0) d, Z=0.675, P=0.500], oxygen therapy duration [32.0(14.0, 96.3) h vs.39.0 (24.0, 83.2) h, Z=0.094, P=0.925], the recovery rate from clinical symptoms during treatment [(105/106, 99.1%) vs.(96/101, 95.0%)], and recurrence rate [(0/106, 0) vs.(2/101, 2.0%)] between the 2 groups (all P>0.05).However, the above-mentioned four indicators in the experimental group showed a trend of clinical benefits.The quantitative virus detection results showed that the RSV viral load in both groups decreased after treatment compared to before treatment.After 2 days of treatment, the decline rate of RSV viral load from the baseline was 0.90 lg copies/(mL·d) in the experimental group and 0.25 lg copies/(mL·d)in the control group, with a statistically significant difference ( P<0.05).Furthermore, there was no statistically significant difference in the incidence of adverse reactions between the 2 groups ( P>0.05).Importantly, no drug-related serious adverse reactions occurred in both groups. Conclusions:The nebulized inhalation therapy of IFN α1b demonstrates efficacy and safety in treating pediatric RSV associated lower respiratory tract infections.It particularly offers outstanding clinical therapeutic value for severe children.

Objective:To investigate the impact of abnormal patterns of 75 g oral glucose tolerance test (OGTT) in the second trimester on the risk of large for gestational age (LGA) newborn deliveries.Methods:General clinical data and OGTT results of 66 290 pregnant women who received regular prenatal care and delivered in Guangdong Maternal and Child Health Hospital from December 24, 2016 to July 26, 2022 were collected. According to the results of OGTT, the pregnant women were divided into 8 groups: normal blood glucose group (normal fasting blood glucose, 1-hour and 2-hour after oral glucose, 54 518 cases), gestational diabetes mellitus (GDM) 0 group (only abnormal fasting blood glucose, 1 430 cases), GDM 1 group (only abnormal blood glucose at 1-hour after oral glucose, 2 150 cases), GDM 2 group (only abnormal blood glucose at 2-hour after oral glucose, 3 736 cases), GDM 0+1 group (both fasting blood glucose and 1-hour after oral glucose were abnormal, 371 cases), GDM 0+2 group (both fasting blood glucose and 2-hour after oral glucose were abnormal, 280 cases), GDM 1+2 group (abnormal blood glucose at 1-hour and 2-hour after oral glucose, 2 981 cases) and GDM 0+1+2 group (abnormal fasting blood glucose, 1-hour and 2-hour after oral glucose, 824 cases). Multivariate logistic regression was used to analyze the effects of different abnormal OGTT patterns on LGA. In addition, the blood glucose measurements at the three time points of OGTT were combined and used as continuous variables in the receiver operating characteristic (ROC) curve to evaluate the predictive value of each blood glucose measurement mode for LGA and the area under the curve (AUC) was compared.Results:(1) Multivariate logistic regression analysis showed that the risks of LGA were significantly increased in GDM 0 group ( OR=1.76, 95% CI: 1.50-2.08; P<0.001), GDM 0+1 group ( OR=2.29, 95% CI: 1.72-3.04; P<0.001), and GDM 0+1+2 group ( OR=1.98, 95% CI: 1.61-2.43; P<0.001). (2) ROC curve analysis showed that fasting blood glucose, 1-hour after oral glucose, 2-hour after oral glucose, fasting+1-hour after oral glucose, fasting+2-hour after oral glucose, 1-hour+2-hour after oral glucose, and fasting+1-hour+2-hour after oral glucose had certain predictive value for LGA (all P<0.001). The AUC of fasting blood glucose measurement was higher than that of 2-hour blood glucose measurement in predicting LGA, and the difference was statistically significant ( P<0.05). There was no significant difference in the AUC between fasting blood glucose and other blood glucose measurement modes for predicting LGA (all P>0.05). Conclusions:In the abnormal OGTT patterns, pregnant women with abnormal fasting blood glucose, abnormal fasting+1-hour after oral glucose, and abnormal fasting+1-hour+2-hour after oral glucose have an increased risk of LGA. Fasting blood glucose measurement is of great significance for the prediction of LGA, and could be used as an optimal indicator to evaluate the risk of LGA in clinical practice.

Objective:To establish a foundation for the psychological selection of air combat personnel by studying the cognitive ability measurement methods for air combat personnel.Methods:The tests were done for 390 subjects including 142 radar operators, 117 radar academy students, 45 air combat personnel, and 86 radar trainees. Based on job analysis, 5 cognitive test tasks were developed, including graphic discrimination, working memory test, target tracking, voice anti-jamming, and comprehensive management. The discrimination was evaluated by the distribution graphs and coefficients of variation of the test results. The criterion-related validity was examined by correlating the cognitive test scores with the participants' work performance or academic grades, which served as the criteria. Content validity was determined by a 9-level scoring (1-9) of task necessity that collected from 30 air combat personnel and by the assessments of necessity of tested abilities that came from 30 experts. The parallel forms reliability, test-retest reliability and split-half reliability were tested respectively according to the results of each test.Results:The original scores of each test showed approximate normal distribution. The selected indicators' coefficients of variation were 14.4%-111.0%, reliabilities were 0.764-0.827, and criterion-related validities were 0.186-0.445, all of which were statistically significant (all P<0.05). In 30 air combat personnel, 53.3%-83.3% scored 7-9 to the necessity of test items, and 93.3% of 30 experts gave the required or basically required evaluations to the test items. Conclusions:The series tests show good content validity, and discrimination, reliability and the criterion-related validity meet the requirements of psychometrics. Especially the tests of graphic discrimination, working memory and target tracking expressed higher degree of discrimination, and can be used as cognitive ability assessment tool for the selection of air combat personnel.

Objective:To establish a foundation for the psychological selection of air combat personnel by studying the cognitive ability measurement methods for air combat personnel.Methods:The tests were done for 390 subjects including 142 radar operators, 117 radar academy students, 45 air combat personnel, and 86 radar trainees. Based on job analysis, 5 cognitive test tasks were developed, including graphic discrimination, working memory test, target tracking, voice anti-jamming, and comprehensive management. The discrimination was evaluated by the distribution graphs and coefficients of variation of the test results. The criterion-related validity was examined by correlating the cognitive test scores with the participants' work performance or academic grades, which served as the criteria. Content validity was determined by a 9-level scoring (1-9) of task necessity that collected from 30 air combat personnel and by the assessments of necessity of tested abilities that came from 30 experts. The parallel forms reliability, test-retest reliability and split-half reliability were tested respectively according to the results of each test.Results:The original scores of each test showed approximate normal distribution. The selected indicators' coefficients of variation were 14.4%-111.0%, reliabilities were 0.764-0.827, and criterion-related validities were 0.186-0.445, all of which were statistically significant (all P<0.05). In 30 air combat personnel, 53.3%-83.3% scored 7-9 to the necessity of test items, and 93.3% of 30 experts gave the required or basically required evaluations to the test items. Conclusions:The series tests show good content validity, and discrimination, reliability and the criterion-related validity meet the requirements of psychometrics. Especially the tests of graphic discrimination, working memory and target tracking expressed higher degree of discrimination, and can be used as cognitive ability assessment tool for the selection of air combat personnel.

Diacylglycerol (DAG) is an intermediate product in lipid metabolism and plays an important physiological role in human body. It is mainly prepared by hydrolyzing lipid with lipase. However, research on the detection method of 1, 2-diacylglycerol (1, 2-DAG) and 1, 3-diacylglycerol (1, 3-DAG) and catalytic specificity of lipase was not enough, which limits its wide application. To address these challenges, an efficient quantitative detection method was first established for 1, 2-DAG (0.025-0.200 g/L) and 1, 3-DAG (0.025-0.150 g/L) by combining supercritical fluid chromatography with evaporative light scattering detector and optimizing the detection and analysis parameters. Based on the molecular docking between Thermomyces lanuginosus lipase (TLL) and triolein, five potential substrate binding sites were selected for site-specific saturation mutation to construct a mutation library for enzyme activity and position specificity screening. The specificity of sn-1, 3 of the I202V mutant was the highest in the library, which was 11.7% higher than the specificity of the wild type TLL. In summary, the position specificity of TLL was modified based on a semi-rational design, and an efficient separation and detection method of DAG isomers was also established, which provided a reference for the study of the catalytic specificity of lipase.
Humans ; Diglycerides ; Molecular Docking Simulation ; Binding Sites ; Catalysis ; Lipase/genetics*

Objective:To explore the application and practice of "flipped classroom" in the teaching of general surgery interns.Methods:A total of 20 internship groups (3 to 5 people in each group) were randomly selected from the general surgery practice group in the Department of General Surgery of the Second Clinical Medical College of North Sichuan Medical College. They were randomly divided into the flipped group (45 people) and the traditional group (40 people), with 10 subgroups in each group. The flipped group adopted the flipped classroom teaching mode (students' self-study by handing out materials before class, students and teachers' discussion in class, and students and teachers' evaluation after class), while the control group adopted the current conventional teaching mode (students' preview before class, teachers' explanation in class, and teachers' question answering after class). At the end of the teaching, a questionnaire was used to evaluate the participation and completion of each student. The teaching effect was evaluated by medical history collection and case analysis. The participation, completion, and teaching effect between the two groups were compared and analyzed. SPSS 23.0 software was used for t-test and Chi-square test. Results:The participation of the flipped group was better than that of the traditional group [(17.45±1.83) vs. (15.57±1.52)], and the difference was statistically significant ( P < 0.05). There was no statistically significant difference between the flipped group and the traditional group. There was no significant difference in medical history collection scores between the two groups. The case analysis of the flipped group was better than that of the traditional group [(87.30±6.06) vs. (81.50±5.88), P < 0.05]. The questionnaire shows that about 90% of the students think that flipped classroom can improve their interest in learning [96% (43/45)], improve their autonomous learning ability [89% (40/45)], and have better learning effect. At the same time, 78% (35/45) of students think that learning time is too long. Conclusion:The flipped classroom teaching model can improve the teaching participation of general surgery students, improve students' interest in learning, improve their self-learning ability, and improve students' thinking ability of medical record analysis.