Sennoside A (SA), a typical prodrug, exerts its laxative effect only after its transformation into rheinanthrone catalyzed by gut microbial hydrolases and reductases. Hydrolases have been identified, but reductases remain unknown. By linking a photoreactive group to the SA scaffold, we synthesized a photoaffinity probe to covalently label SA reductases and identified SA reductases using activity-based protein profiling (ABPP). From lysates of an active strain, Bifidobacterium pseudocatenulatum (B. pseudocatenulatum), 397 proteins were enriched and subsequently identified using mass spectrometry (MS). Among these proteins, chromate reductase/nicotinamide adenine dinucleotide (NADH) phosphate (NADPH)-dependent flavin mononucleotide (FMN) reductase/oxygen-insensitive NADPH nitroreductase (nfrA) was identified as a potent SA reductase through further bioinformatic analysis and The Universal Protein Resource (UniProt) database screening. We also determined that recombinant nfrA could reduce SA. Our study contributes to further illuminating mechanisms of SA transformation to rheinanthrone and simultaneously offers an effective method to identify gut bacterial reductases.

Sennoside A(SA),a typical prodrug,exerts its laxative effect only after its transformation into rhei-nanthrone catalyzed by gut microbial hydrolases and reductases.Hydrolases have been identified,but reductases remain unknown.By linking a photoreactive group to the SA scaffold,we synthesized a photoaffinity probe to covalently label SA reductases and identified SA reductases using activity-based protein profiling(ABPP).From lysates of an active strain,Bifidobacterium pseudocatenulatum(B.pseu-docatenulatum),397 proteins were enriched and subsequently identified using mass spectrometry(MS).Among these proteins,chromate reductase/nicotinamide adenine dinucleotide(NADH)phosphate(NADPH)-dependent flavin mononucleotide(FMN)reductase/oxygen-insensitive NADPH nitroreductase(nfrA)was identified as a potent SA reductase through further bioinformatic analysis and The Universal Protein Resource(UniProt)database screening.We also determined that recombinant nfrA could reduce SA.Our study contributes to further illuminating mechanisms of SA transformation to rheinanthrone and simultaneously offers an effective method to identify gut bacterial reductases.

By conducting retrospective analysis, this study aim to investigate the resistance mechanism of quinolones in non-typhoidal Salmonella (NTS). A total of 105 strains of NTS isolated from clinical specimens from the Fifth Affiliated Hospital of Southern Medical University from May 2020 to February 2021 were used as research objects. VITEK2 Compact automatic identification drug sensitivity analysis system and serological test were used to identify the strains. The sensitivity of the strains to ciprofloxacin, levofloxacin and nalidixic acid was detected by AGAR dilution method. The whole genome of 105 strains of NTS was sequenced. Abricate and other softwares were used to analyze drug-resistant genes, including plasmid-mediated quinolone resistance gene (PMQR) and Quinolone resistance determination region (QRDR). Serotypes and ST types were analyzed using SISTR and MLST, and phylogenetic trees were constructed. The results showed that the NTS isolated in this region were mainly ST34 Salmonella typhimurium (53.3%). The drug sensitivity results showed that the drug resistance rates of NTS to ciprofloxacin, levofloxacin and nalidixic acid were 30.4%, 1.9% and 22.0%, respectively, and the intermediate rates of ciprofloxacin and levofloxacin were 27.6% and 54.2%.A total of 46 (74.2%) of the 62 quinolone non-susceptible strains carried the PMQR gene, mainly qnrS1 (80.4%), followed by aac(6′)-Ib-cr(15.2%); there were 14 NTS and 8 NTS had gyrA and parC gene mutations, respectively. The gyrA was mutations at the amino acid position 87, Asp87Tyr, Asp87Asn, Asp87Gly, and Thr57Ser mutations were detected in parC. In conclusion, this study found that NTS had relatively high resistance to quinolones, carrying qnrS1 gene mainly resulted in decreased sensitivity of NTS to ciprofloxacin and levofloxacin, and gyrA:87 mutation mainly resulted in NTS resistance to Nalidixic acid; Salmonella typhimurium in clinical isolates showed clonal transmission and required further epidemiological surveillance.

By conducting retrospective analysis, this study aim to investigate the resistance mechanism of quinolones in non-typhoidal Salmonella (NTS). A total of 105 strains of NTS isolated from clinical specimens from the Fifth Affiliated Hospital of Southern Medical University from May 2020 to February 2021 were used as research objects. VITEK2 Compact automatic identification drug sensitivity analysis system and serological test were used to identify the strains. The sensitivity of the strains to ciprofloxacin, levofloxacin and nalidixic acid was detected by AGAR dilution method. The whole genome of 105 strains of NTS was sequenced. Abricate and other softwares were used to analyze drug-resistant genes, including plasmid-mediated quinolone resistance gene (PMQR) and Quinolone resistance determination region (QRDR). Serotypes and ST types were analyzed using SISTR and MLST, and phylogenetic trees were constructed. The results showed that the NTS isolated in this region were mainly ST34 Salmonella typhimurium (53.3%). The drug sensitivity results showed that the drug resistance rates of NTS to ciprofloxacin, levofloxacin and nalidixic acid were 30.4%, 1.9% and 22.0%, respectively, and the intermediate rates of ciprofloxacin and levofloxacin were 27.6% and 54.2%.A total of 46 (74.2%) of the 62 quinolone non-susceptible strains carried the PMQR gene, mainly qnrS1 (80.4%), followed by aac(6′)-Ib-cr(15.2%); there were 14 NTS and 8 NTS had gyrA and parC gene mutations, respectively. The gyrA was mutations at the amino acid position 87, Asp87Tyr, Asp87Asn, Asp87Gly, and Thr57Ser mutations were detected in parC. In conclusion, this study found that NTS had relatively high resistance to quinolones, carrying qnrS1 gene mainly resulted in decreased sensitivity of NTS to ciprofloxacin and levofloxacin, and gyrA:87 mutation mainly resulted in NTS resistance to Nalidixic acid; Salmonella typhimurium in clinical isolates showed clonal transmission and required further epidemiological surveillance.

The comprehensive detection and identification of active ingredients in complex matrices is a crucial challenge.Liquid chromatography coupled with high-resolution mass spectrometry(LC-HRMS)is the most prominent analytical platform for the exploration of novel active compounds from complex matrices.However,the LC-HRMS-based analysis workflow suffers from several bottleneck issues,such as trace content of target compounds,limited acquisition for fragment information,and uncertainty in interpreting relevant MS2 spectra.Lycibarbarspermidines are vital antioxidant active ingredients in Lycii Fructus,while the reported structures are merely focused on dicaffeoylspermidines due to their low content.To comprehensively detect the new structures of lycibarbarspermidine derivatives,a"depict"strategy was developed in this study.First,potential new lycibarbarspermidine derivatives were designed according to the biosynthetic pathway,and a comprehensive database was established,which enlarged the coverage of lycibarbarspermidine derivatives.Second,the polarity-oriented sample prep-aration of potential new compounds increased the concentration of the target compounds.Third,the construction of the molecular network based on the fragmentation pathway of lycibarbarspermidine derivatives broadened the comprehensiveness of identification.Finally,the weak response signals were captured by data-dependent scanning(DDA)followed by parallel reaction monitoring(PRM),and the efficiency of acquiring MS2 fragment ions of target compounds was significantly improved.Based on the integrated strategy above,210 lycibarbarspermidine derivatives were detected and identified from Lycii Fructus,and in particular,170 potential new compounds were structurally characterized.The integrated strategy improved the sensitivity of detection and the coverage of low-response components,and it is expected to be a promising pipeline for discovering new compounds.

Objective::To explore the risk factors and pregnancy outcomes in women with a history of cesarean section complicated by placenta accreta (PA).Methods::This case-control study included clinical data from singleton mothers with a history of cesarean section in 11 public tertiary hospitals in seven provinces of China between January 2017 and December 2017. According to the intraoperative findings after delivery, the study population was divided into PA and non-PA groups. We compared the pregnancy outcomes between the two groups, used multivariate logistic regression to analyze the risk factors for placental accreta.Results::For this study we included 11,074 pregnant women with a history of cesarean section; and of these, 869 cases were in the PA group and 10,205 cases were in the non-PA group. Compared with the non-PA group, the probability of postpartum hemorrhage (236/10,205, 2.31% vs. 283/869, 32.57%), severe postpartum hemorrhage (89/10,205, 0.87% vs. 186/869, 21.75%), diffuse intravascular coagulation (3/10,205, 0.03% vs. 4/869, 0.46%), puerperal infection (33/10,205, 0.32% vs. 12/869, 1.38%), intraoperative bladder injury (1/10,205, 0.01% vs. 16/869, 1.84%), hysterectomy (130/10,205, 1.27% vs. 59/869, 6.79%), and blood transfusion (328/10,205,3.21 % vs. 231/869,26.58%) was significantly increased in the PA group ( P < 0.05). At the same time, the neonatal birth weight (3250.00 (2950.00-3520.00) g vs. 2920.00 (2530.00-3250.00) g), the probability of neonatal comorbidities (245/10,205, 2.40% vs. 61/869, 7.02%), and the rate of neonatal intensive care unit admission (817/10,205, 8.01% vs. 210/869, 24.17%) also increased significantly ( P < 0.05). Weight (odds ratio ( OR)= 1.03, 95% confidence interval ( CI): 1.01-1.05)), parity ( OR= 1.18, 95% CI: 1.03-1.34), number of miscarriages ( OR= 1.31, 95% CI: 1.17-1.47), number of previous cesarean sections ( OR= 2.57, 95% CI: 2.02-3.26), history of premature rupture of membrane ( OR= 1.61, 95% CI: 1.32-1.96), previous cesarean-section transverse incisions ( OR= 1.38, 95% CI: 1.12-1.69), history of placenta previa ( OR= 2.44,95% CI: 1.50-3.96), and the combination of prenatal hemorrhage ( OR= 9.95,95% CI: 8.42-11.75) and placenta previa ( OR= 91.74, 95% CI: 74.11-113.56) were all independent risk factors for PA. Conclusion::There was an increased risk of adverse outcomes in pregnancies complicated by PA in women with a history of cesarean section, and this required close clinical attention. Weight before pregnancy, parity, number of miscarriages, number of previous cesarean sections, history of premature rupture of membranes, past transverse incisions in cesarean sections, a history of placenta previa, prenatal hemorrhage, and placenta previa were independent risk factors for pregnancies complicated with PA in women with a history of cesarean section. These independent risk factors showed a high value in predicting the risk for placentab accreta in pregnancies of women with a history of cesarean section.

Objective::To explore the risk factors and pregnancy outcomes in women with a history of cesarean section complicated by placenta accreta (PA).Methods::This case-control study included clinical data from singleton mothers with a history of cesarean section in 11 public tertiary hospitals in seven provinces of China between January 2017 and December 2017. According to the intraoperative findings after delivery, the study population was divided into PA and non-PA groups. We compared the pregnancy outcomes between the two groups, used multivariate logistic regression to analyze the risk factors for placental accreta.Results::For this study we included 11,074 pregnant women with a history of cesarean section; and of these, 869 cases were in the PA group and 10,205 cases were in the non-PA group. Compared with the non-PA group, the probability of postpartum hemorrhage (236/10,205, 2.31% vs. 283/869, 32.57%), severe postpartum hemorrhage (89/10,205, 0.87% vs. 186/869, 21.75%), diffuse intravascular coagulation (3/10,205, 0.03% vs. 4/869, 0.46%), puerperal infection (33/10,205, 0.32% vs. 12/869, 1.38%), intraoperative bladder injury (1/10,205, 0.01% vs. 16/869, 1.84%), hysterectomy (130/10,205, 1.27% vs. 59/869, 6.79%), and blood transfusion (328/10,205,3.21 % vs. 231/869,26.58%) was significantly increased in the PA group ( P < 0.05). At the same time, the neonatal birth weight (3250.00 (2950.00-3520.00) g vs. 2920.00 (2530.00-3250.00) g), the probability of neonatal comorbidities (245/10,205, 2.40% vs. 61/869, 7.02%), and the rate of neonatal intensive care unit admission (817/10,205, 8.01% vs. 210/869, 24.17%) also increased significantly ( P < 0.05). Weight (odds ratio ( OR)= 1.03, 95% confidence interval ( CI): 1.01-1.05)), parity ( OR= 1.18, 95% CI: 1.03-1.34), number of miscarriages ( OR= 1.31, 95% CI: 1.17-1.47), number of previous cesarean sections ( OR= 2.57, 95% CI: 2.02-3.26), history of premature rupture of membrane ( OR= 1.61, 95% CI: 1.32-1.96), previous cesarean-section transverse incisions ( OR= 1.38, 95% CI: 1.12-1.69), history of placenta previa ( OR= 2.44,95% CI: 1.50-3.96), and the combination of prenatal hemorrhage ( OR= 9.95,95% CI: 8.42-11.75) and placenta previa ( OR= 91.74, 95% CI: 74.11-113.56) were all independent risk factors for PA. Conclusion::There was an increased risk of adverse outcomes in pregnancies complicated by PA in women with a history of cesarean section, and this required close clinical attention. Weight before pregnancy, parity, number of miscarriages, number of previous cesarean sections, history of premature rupture of membranes, past transverse incisions in cesarean sections, a history of placenta previa, prenatal hemorrhage, and placenta previa were independent risk factors for pregnancies complicated with PA in women with a history of cesarean section. These independent risk factors showed a high value in predicting the risk for placentab accreta in pregnancies of women with a history of cesarean section.

Objective:To evaluate the efficacy of combination of toy and cartoon video-assisted admission in preventing agitation during recovery from general anesthesia in preschool children.Methods:Totally 96 children who undergoing elective surgery from July 2018 to October 2019 in Guangzhou Women and Children′s Medical Center were divided into experimental group ( n=48) and control group ( n=48). Two groups were admitted to the general preoperative waiting room for 60 minutes before the operation, and children in the experimental group recieved toy and cartoon video combination intervention, while children in the control group were subjected to routine nursing intervention. The children′s agitation was assessed by using Pediatric Anesthesia Emergence Delirium Scale (PAED) when children entered the post-anesthesia care unit (PACU), 10 minutes after in PACU and leave PACU. In addition, the vital signs such as blood pressure, heart rate, respiratory rate of the two groups were also recorded. Results:The emergence time and duration of PACU stay in the experimental group were (17.19±1.76) minutes and (22.47±2.36) minutes, significantly shortern than in the control group (18.36±2.19) minutes and (23.82±2.62) minutes, the difference was statistically significant ( t values were 2.760, 2.546, P<0.05). 10 minutes after in PACU and out of PACU, the PAED scores, systolic pressure, heart rate, respiratory rate was [7.56±1.86, 4.60±1.19, (108.12±10.19)mmHg, (102.72±8.55) mmHg, (112.91±6.10) times/minute, (106.39±6.75) times/minute, (18.87±1.98) times/minute, (17.49±1.68) times/minute], significantly lower than those in the control group [13.40±1.47, 6.71±2.21, (116.73±14.17)mmHg, (107.62±12.44) mmHg, (121.07±8.07) times/minute, (114.69±5.78) times/minute, (20.96±1.86) times/minute, (18.47±1.63) times/minute], the difference was statistically significant ( t values were 2.162-16.332, P<0.05). Conclusion:Toy and cartoon video combine-assisted admission can reduce the agitation and stable vital signs during recovery from general anesthesia in preschool children.

Objective:To investigate the clusters of COVID-19 associated with a market (market Y) in Haidian District, Beijing, and analyze the chain of transmission and provide reference for effective prevention and control of COVID-19.Methods:The investigation of field epidemiology and cluster epidemic was used to describe the distributions of all COVID-19 cases. The time sequence diagram of the cases, disease onset was drawn and transmission chains were analyzed. Real-time RT-PCR assay was conducted for SARS-CoV-2 nucleic acid test by using the respiratory samples of the cases.Results:The COVID-19 epidemic, originated from a wholesale farm produce market (market X) in Fengtai District, Beijing, was introduced by a marketer in the market Y who had exposed to market X, causing 8 clusters of 20 confirmed cases of COVID-19 and one asymptomatic case, including 8 men and 13 women, in market Y, surrounding communities, food plaza, companies,families and other places. The incidence peaked during June 10-14, 2020; the median age of the cases was 45 years, ranging from 5 years to 87 years. The initial symptoms of the cases included fever (10/20) and pharynx discomfort (7/20). The median of incubation period was 5 days ( IQR:3-8). The median of serial interval between primary case and secondary cases was 5 days with a secondary attack rate of 3.7%(20/538), and the secondary attack rate in household close-contacts was 14.0% (7/50). Conclusions:The clusters of COVID-19 associated with market Y were caused by several modes of transmission, including human-to-human, contaminated material-to-human, etc. The combined public-health response measures were effective to control the COVID-19 epidemic in Haidian district of Beijing.

Objectives To explore the perceived stigma among family members of people with schizophrenia and to identify the influential factors related to perceived stigma in socio-demographic characters of family members and patient characters.Methods Total 127 family members of people with schizophrenia in a psychiatric hospital in Beijing were surveyed by the Perceived Devaluation-Discrimination Scale developed by Link.Results The mean score of the perceived devaluation-discrimination scale is 2.60±0.44.It was significantly higher than the 2.5 midpoint(t=2.53,P<0.05).Family member's perceived stigma was significantly different between different groups of residence area,education level,occupation and family income (P<0.05).Perceived stigma were not affected by patient characters (P>0.05).Family members'education level was the influencing factors of stigma,and the R~2 Square is 0.213.Conclusions The family members of people with schizophrenia suffered from high stigma.Education level of family member may be one of the influential factors.