Accurate analysis of metal nanoparticles(MNPs)in sediments is a prerequisite for assessing the ecological risks of MNPs in aquatic environmental sediments.In this study,an analytical method for quantitative detection of concentration and particle size distribution of silver-containing nanoparticles(Ag-NPs),zinc-containing nanoparticles(Zn-NPs),cerium-containing nanoparticles(Ce-NPs),and titanium-containing nanoparticles(Ti-NPs)in sediments was established based on ultrasonic extraction-single particle inductively coupled plasma mass spectrometry(SP-ICP-MS).The effects of sample preparation conditions such as extraction solvent type,solid-liquid ratio,ultrasonic time,and settling time on the recovery of MNPs were investigated.The results showed that the extraction of MNPs from sediment by distilled water could effectively eliminate the high background signal interference introduced by the extractant under the conditions of solid-liquid ratio of 1∶400(g∶mL),ultrasonic extraction time of 1 h and settling time of 3 h.The detection limits for particle size of Ag-NPs,Zn-NPs,Ce-NPs and Ti-NPs in sediments were 31,35,26 and 85 nm,respectively,while the detection limits of particle concentrations were 1.21×104,1.90×104,5.26×107 and 1.48×107 particles/g,respectively.The spiking recoveries of Ag-NPs,Zn-NPs,Ce-NPs and Ti-NPs in sediments were 62.1％-108.7％,with relative standard deviations below 10％.This method could rapidly,accurately and simultaneously determine the concentration and particle size distribution of various MNPs in sediments,and was successfully applied to analysis of Ag-NPs,Zn-NPs,Ce-NPs,and Ti-NPs in authentic marine sediments.

Type Ⅵ secretion system(T6SS)is a lethal weapon that releases effectors in direct contact to kill eukaryotic predators or prokaryotic competitors.T6SS is of great significance in bacterial environmental adaptability,pathogenicity,and gene horizontal transfer.T6SS has been identified in about 25％of Gram-negative bacteria.Because of its widespread existence,T6SS is considered the key factor of ecological competition.T6SS effectors exerting biological functions have high diversity and do not have conserved sequences,and the regulatory mechanisms involved are complex.Therefore,it is a hot and difficult topic in T6SS research.Vibrio fluvialis(V.fluvialis)as a newly emerging foodborne pathogen,has unique characteristics in the quantity,composition,and physiological function of T6SS,which is related to its wide environmental adaptability and pathoge-nicity.This article mainly reviews the research progress of V.fluvialis T6SS,including its composition,structure,functional activity,and regulatory mechanism.

Pharmaceutical cocrystals is an advanced technology to improve the physicochemical and biological properties of drugs. However, there are few studies on the in vivo metabolism of pharmaceutical cocrystals. In this study, the pharmacokinetics of wogonin cocrystal in normal rats was further studied on the basis of the previous preparation of wogonin-aloperine cocrystal. Firstly, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for simultaneous determination of wogonin and its metabolite wogonoside in rat plasma, and to investigate the methodology. The method was applied to the pharmacokinetic study of wogonin-aloperine cocrystal (Wog-Alop) in rats. The results showed that wogonin and its metabolite wogonoside had a good linear relationship in the range of 1-800 ng·mL^-1, and the precision, accuracy, matrix effect and stability in this range met the requirements of biological analysis. Compared with direct administration of wogonin, the C_max of wogonin and its metabolite in rats increased to 7.44-fold and 9.15-fold, AUC_0-t increased to 1.67-fold and 3.72-fold, and oral bioavailability of wogonin increased to 187.66% after cocrystal administration. Wog-Alop cocrystal can significantly improve the C_max, AUC, and oral bioavailability of wogonin and its metabolite, which provides a new perspective for the clinical application of wogonin. This study was approved by the Experimental Animal Ethics Review Committee of Beijing University of Chinese Medicine (approval number: BUCM-2023032307-1148).

Exploring the risk "time interval window" of sequential medication of Reduning injection (RDN) and penicillin G injection (PG) by detecting the correlation between serum biochemical indexes and plasma metabonomic characteristics, in order to reduce the risk of adverse reactions caused by the combination of RDN and PG. All animal experiments and welfare are in accordance with the requirements of the First Affiliated Experimental Animal Ethics and Animal Welfare Committee of Henan University of Chinese Medicine (approval number: YFYDW2020002). The changes of biochemical indexes in serum of rats were detected by enzyme-linked immunosorbent assay. It was determined that RDN combined with PG could cause pseudo-allergic reactions (PARs) activated by complement pathway. Further investigation was carried out at different time intervals (1.5, 2, 3.5, 4, 6, and 8 h PG+RDN). It was found that sequential administration within 3.5 h could cause significant PARs. However, PARs were significantly reduced after administration interval of more than 4 h. LC-MS was used for plasma metabolomics analysis, and the levels of serum biochemical indicators and plasma metabolic profile characteristics were compared in parallel. 22 differential metabolites showed similar or opposite trends to biochemical indicators before and after 3.5 h. And enriched to 10 PARs-related pathways such as arachidonic acid metabolism, steroid hormone biosynthesis, linoleic acid metabolism, glycerophospholipid metabolism, and tryptophan metabolism. In conclusion, there is a risk "time interval window" phenomenon in the adverse drug reactions caused by the sequential use of RDN and PG, and the interval medication after the "time interval window" can significantly reduce the risk of adverse reactions.

Based on the strategy of metabolomics combined with bioinformatics, this study analyzed the potential allergens and mechanism of pseudo-allergic reactions (PARs) induced by the combined use of Reduning injection and penicillin G injection. All animal experiments and welfare are in accordance with the requirements of the First Affiliated Experimental Animal Ethics and Animal Welfare Committee of Henan University of Chinese Medicine (approval number: YFYDW2020002). Based on UPLC-Q-TOF/MS technology combined with UNIFI software, a total of 21 compounds were identified in Reduning and penicillin G mixed injection. Based on molecular docking technology, 10 potential allergens with strong binding activity to MrgprX2 agonist sites were further screened. Metabolomics analysis using UPLC-Q-TOF/MS technology revealed that 34 differential metabolites such as arachidonic acid, phosphatidylcholine, phosphatidylserine, prostaglandins, and leukotrienes were endogenous differential metabolites of PARs caused by combined use of Reduning injection and penicillin G injection. Through the analysis of the "potential allergen-target-endogenous differential metabolite" interaction network, the chlorogenic acids (such as chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, and isochlorogenic acid A) and β-lactam allergens in the combination of the two may be mainly regulated by PLD1, PLA2G12A and CYP1A1. The three upstream signal target proteins mainly activate the arachidonic acid metabolic pathway, promote the degranulation of mast cells, release downstream endogenous inflammatory mediators, and induce PARs.

Objective To evalute the drug resistance characteristics of tuberculosis(TB)patients of all ages in Guangdong Province during 2014-2020,and provide prevention and treatment strategies of tuberculosis.Method We used 39,048 clinical isolates of Mycobacterium tuberculosis(MTB)belonging to patients with confirmed TB from 2014 to 2020,from 32 TB drug-resistant surveillance sites in Guangdong Province,and we retrospectively analyzed the laboratories data of patients with drug-resistant TB,and grouped patients by age and region,to explore the trend of drug-resistance of MTB clinical isolates,the trend and incidence differences of multi-resistant TB(including monodrug-resistant TB(MR-TB),polydrug-resistant TB(PDR-TB),multidrug-resistant TB(MDR-TB)and exten-sively drug-resistant TB(XDR-TB)),and resistance characteristics of MTB clinical isolates to drugs in focus(rifam-picin and ofloxacin).Result The differences in the resistance rates of MTB clinical isolates to nine antituberculosis drugs among patients at 32 TB drug resistance surveillance sites in Guangdong Province from 2014 to 2020 were not statistically significant(P>0.05).The rates of MR-TB,PDR-TB,MDR-TB,XDR-TB,and total resistance isolates of MTB clinical isolates were 14.46%,5.16%,5.16%,4.58%,and 1.29%,respectively.he pediatric group had a higher MR rate(15.4%)than the adult and geriatric groups,while the adult and geriatric groups had higher MDR rates(5.0%and 5.0%,respectively).The geriatric group also had a higher XDR rate(2.1%),with statistically significant differences(P<0.001).The rates of MR-TB(14.8%),PDR-TB(5.3%),MDR-TB(4.7%),XDR-TB(1.4%),ofloxacin resistance(11.33%)and rifampicin resistance(6.92%)of MTB clinical isolates were higher in patients from the Pearl River Delta than in other regions of Guangdong Province,with statistically significant differ-ences(P<0.001).Conclusion According to the data from the surveillance sites,the epidemiological trend of drug-resistant TB in Guangdong Province is leveling off during the period 2014-2020.However,the incidence of drug-resistant TB is higher in specific populations(e.g.children and the elderly),and the incidence of drug-resistant TB and the rate of drug resistance to drugs in focus are higher in the Pearl River Delta than in other regions of Guang-dong Province,necessitating further investigation and the development of novel prevention and control strategies.

Objective:This study aimed to assess the effects of Peer Balint-style group on the empathy ability of third-year long-term medical students and to provide a theoretical and practical reference for effectively improving their humanistic quality.Methods:Ninety third-year Chinese long-term medicine students participated. Volunteers received either ten sessions of 1.5-h Peer Balint-style group which were led by specially trained peers from June 2019 to August 2019. The College Students' Empathy Ability Questionnaire was used before the experiment and the second day after the experiment. The total score of the scale from the pre-test and post-test and the scores of each dimension conformed to a normal distribution, with equal variance, describing in the form of ( x± s). Paired t-tests were performed to compare the total score and each dimension score before and after the intervention, using SPSS 22.0. Semi-structured interviews were conducted with 7 peer-group leaders and group members after the clinical practice period. The interview materials were analyzed by traditional content analysis. The content of the qualitative research was open-coded to obtain 10 categories, suggesting the role and inadequacy of Peer Balint-style groups. Results:A total of 63 valid samples were obtained. There was no significant difference of ( t=-0.44, P=0.661, P>0.05) between the total score of the post-test (118.00±11.98) and the total score of the pre-test (117.38±12.36). In each dimension, the reverse comprehension score of post-test (9.06±1.97) was significantly different ( t=-2.08, P=0.041, P>0.05) from the pre-test's (8.57±2.15), which increased compared to the pre-test score. Conclusions:Peer Balint-style group had a positive effect on improving empathy among medical students. Compared with the traditional Balint group, it has wider coverage, higher affinity and greater mobility. However, the design of the Peer Balint-style group still needs to be further improved.