In order to solve the problem of resistance of Pseudomonas aeruginosa to multiple antibiotics, it is an effective way to find inhibitors of P. aeruginosa efflux pump. In this study, 15 new ornithine peptidomimetic derivatives were designed and synthesized by changing the side chain structure of natural amino acids with PAβN, a dipeptide efflux pump inhibitor, and their synergic activity with aztreonam, a monocyclic β-lactam antibiotic, against P. aeruginosa was evaluated. Among them, the representative compound 12b not only enhanced the antibacterial activity of β-lactam antibiotics aztreonam, ceftazidime and meropenem, but also significantly enhanced the antibacterial action of macrolide antibiotics clarithromycin, showing a broad-spectrum synergic sensitization effect. In addition, compound 12b also has a good safety. Preliminary mechanisms suggest that 12b works by directly targeting the efflux transporter MexB. These results provide a new lead compound for the development of a new class of efflux pump inhibitors against P. aeruginosa.

A new method for simultaneous determination of 23 kinds of per-and polyfluoroalkyl substances(PFASs)(13 kinds of perfluoro carboxylic acids,4 kinds of perfluoro sulfonic acids,and 6 kinds of new substitutes)in plant leaf tissue by ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)using automatic online solid phase extraction(SPE)to remove the matrix interference components in plant crude extracts was developed.The plant leaf samples were extracted twice with 1%formic acid-methanol solution,then evaporated to dry,redissolved with 70%methanol solution,and directly injected for analysis.After 23 kinds of target PFASs were purified automatically by online SPE with a WAX column,the six-way valve was switched to rinse PFASs onto an alkaline mobile phase system-compatible C18 analytical column.Then,the 23 kinds of target PFASs were separated within 16 min by gradient elution using a binary mobile phase system of methanol/water(Containing 0.4%ammonium hydroxide).Tandem mass spectrometry was performed in multiple reaction monitoring(MRM)mode for online detection of various PFASs,and quantification was carried out by internal standard method.The results of the method validation showed that satisfactory average recoveries of 23 kinds of PFASs in plant leaf samples(64.2%-125.5%),precision(relative standard deviations(RSDs)of 0.7%-12.8%),linearity(R2＞0.990),and sensitivity(the detection limits(S/N=3)were in the range of 0.02-0.50 μg/kg)were achieved.Finally,this method was used to detect PFASs in the marine green tide algae(Enteromorpha prolifera)and several tree leaves,and a total of 6 kinds of PFASs were detected,in which PFBA was the main contaminant.Compared with the reported offline SPE methods,the proposed online SPE technique significantly simplified the sample pretreatment process and provided an automatic,simple,and environment-friendly method for the routine monitoring of legacy and emerging PFASs in plant tissues.

Objective To explore the efficacy and safety of ticagrelor de-escalation and nicorandil therapy in elderly patients with acute coronary syndrome(ACS)after percutaneous coronary intervention(PCI).Methods A total of 300 elderly patients with ACS were selected from the Sixth and Seventh Medical Center of Chinese PLA General Hospital and Beijing Chaoyang Integrative Medicine Emergency Rescue and First Aid Hospital from November 2016 to June 2019,including 153 males and 147 females,aged>65 years old.All the patients received PCI,and all had double antiplatelet therapy(DAPT)scores≥2 and a new DAPT(PRECISE-DAPT)score of≥25.All patients were divided into two groups by random number table method before operation:ticagrelor group(n=146,ticagrelor 180 mg load dose followed by PCI,and ticagrelor 90 mg bid after surgery)and ticagrelor de-escalation + nicorandil group(n=154,ticagrelor 180 mg load dose followed by PCI,ticagrelor 90 mg bid+nicorandil 5 mg tid after surgery,changed to ticagrelor 60 mg bid+ nicorandil 5 mg tid 6 months later).Follow-up was 12 months.The composite end points of cardiovascular death,myocardial infarction and stroke,the composite end points of mild hemorrhage,minor hemorrhage,other major hemorrhage and major fatal/life-threatening hemorrhage as defined by the PLATO study,and the composite end points of cardiovascular death,myocardial infarction,stroke and bleeding within 12 months in the two groups were observed.Results The comparison of general baseline data between the two groups showed no statistically significant difference(P>0.05).There was also no significant difference in the composite end points of cardiovascular death,myocardial infarction and stroke between the two groups(P>0.05).The cumulative incidence of bleeding events in ticagrelor de-escalation + nicorandil group was significantly lower than that in ticagrelor group(P<0.05),while the composite end points of cardiovascular death,myocardial infarction,stroke and bleeding were also significantly lower than those in tecagrelor group(P<0.05).Conclusion In elderly patients with ACS,the treatment of ticagrelor de-escalation + nicorandil after PCI may not increase the incidence of ischemic events such as cardiovascular death,myocardial infarction or stroke,and it may reduce the incidence of hemorrhagic events.

BACKGROUND:The most prominent transcription factor activated by tumor stem cells in osteosarcoma is EZH2,and silencing of EZH2 has been reported to inhibit osteosarcoma cell growth.Studies have confirmed that bovine serum albumin-chitosan nanoparticles are a drug delivery vector with excellent biocompatibility and biodegradability,and the albumin carrier can provide tumor-targeted drug delivery function. OBJECTIVE:To investigate the effect and mechanism of bovine serum albumin-chitosan nanoparticles loaded with EPZ6438(EZH2 inhibitor)for the treatment of osteosarcoma. METHODS:(1)Bovine serum albumin-chitosan nanoparticles loaded with and without EPZ6438 were prepared.The drug encapsulation rate and drug release rate of serum albumin-chitosan nanoparticles loaded with EPZ6438 were detected.(2)MG-63 cells were divided into four groups and added with PBS(control group),serum albumin-chitosan nanoparticle extract solution(blank nanoparticle group),EPZ6438 solution(free drug group),and serum albumin-chitosan nanoparticle extract loaded with EPZ6438(drug-loaded nanoparticle group),respectively.After 3 days of culture,cell apoptosis was detected by flow cytometry and the expression of caspase-3 mRNA was detected by RT-PCR.(3)Twelve nude mice were selected and the subcutaneous tumor-bearing mouse model was established by injecting MG-63 cell suspension under the armpit.After successful modeling,the mice were randomly divided into four groups for intervention.Normal saline(control group),serum albumin-chitosan nanoparticle solution(blank nanoparticle group),EPZ6438 solution(free drug group)and serum albumin-chitosan nanoparticle solution loaded with EPZ6438(drug-loaded nanoparticle group)were injected into tumor tissues,with three animals in each group.After 7 days of injection,the tumor volume and frozen sections of tumor tissue were observed by TUNEL staining. RESULTS AND CONCLUSION:(1)The drug encapsulation rate of the nanoparticles was about 8.8%,and the nanoparticles had a good drug release effect in pure water.The drug release amount was(34.72±1.93)μg at 24 hours,(48.58±1.10)μg at 72 hours,(49.18±1.24)μg at 120 hours,and(50.25±1.13)μg at 168 hours.The drug release reached the plateau at 120 hours,and the release rate was about 97.9%.(2)After 3 days of cell culture with MG-63,the apoptotic rate in the control group and blank nanoparticle group was lower than that in the free drug group and drug-loaded nanoparticle group(P<0.001),and the expression of caspase 3 mRNA was lower than that in the free drug group and drug-loaded nanoparticle group(P<0.000 1).(3)After 7 days of injection,the tumor volume of nude mice in the drug-loaded nanoparticle group was smaller than that in the other three groups(P<0.05),and the percentage of TUNEL-positive cells in tumor tissue was higher than that in the other three groups(P<0.000 1).(4)The results verify that serum albumin-chitosan nanoparticles loaded with EPZ6438 can inhibit the growth of osteosarcoma by inducing apoptosis of tumor cells.

Objective: To investigate the changes of microorganisms and metabolites in joint effusion of patients with Rheumatoid arthritis(RA), Osteoarthritis(OA) and Urarthritis(UA). To provide new ideas for the study of the effect of microbiota on the pathogenesis of arthritis. Methods: Joint effusion samples were collected from 20 patients with RA, 20 patients with OA, and 20 patients with UA. 16S rRNA gene sequencing and untargeted ultra-high performance Liquid chromatography-mass spectrometry(LC-MS) were used to explore the differences in microorganisms and metabolites among the three groups. Pearson correlation analysis was used to detect the correlation between effusion microbiota and metabolites. Results: There were differences in microbial diversity and microbiota composition among the three groups. Combined with VIP>1 from OPLS-DA andP<0.05 from two-tailed Students t-test, 45 differential metabolites(Between RA and OA groups), 38 differential metabolites(Between UA and OA groups) and 16 differential metabolites(Between RA and UA groups), were identified. GO analysis and KEGG pathway analysis showed that the differential metabolic pathways among the three groups were mainly concentrated in citric acid cycle(TCA cycle), nucleotide metabolism, amino acid metabolism and glycolysis pathway. Correlation analysis of joint effusion microbiota and metabolites suggested that bacteria enriched in the three groups of joint effusion, such asPrevotella,Clostridium ruminosus,Prevotellaceae＿UCG-001, were related to many key metabolites such as lysozyme, uric acid, glucose, and L-glutamine. Conclusion This study shows that there are a variety of bacterial flora in joint cavity effusion of RA, OA, and UA patients, and the differential metabolites produced by them are involved in the pathogenesis of the three types of arthritis by affecting a variety of metabolic pathways.

Objective To construct curcumin pyrazole derivative by the reaction of diketone of curcumin and benzylhydrazine based on the above structure-activity relationship,and to explore its antioxidant activity to provide experimental basis for the development of curcumin antioxidant derivative.Methods Curcumin-N-substituted pyrazole derivative was synthesized from curcumin and benzylhydrazine.The structures of the derivative were confirmed by infrared spectroscopy(IR),nuclear magnetic resonance spectroscopy(1H-NMR,13C-NMR)and LC-MS.The antioxidant activity in vitro of the derivative was evaluated by determination of curcumin and its pyrazole derivative scavenging ability for 2,2-diphenyl-1-picrylhydrazyl(DPPH)free radical and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid(ABTS)free radical.Results Curcumin pyrazole derivative was successfully synthesized.Curcumin and its pyrazole derivative showed good free radical scavenging effects in the range of 4.6-73.6,6.25-100 μg·mL-1,respectively,with a significant dose-effect relationship.The half-maximal inhibition(IC50)values of curcumin and its pyrazole derivatives determined by DPPH method were 14.24,40.37 μg·mL-1,respectively,while the IC50 values of curcumin and its pyrazole derivatives determined by ABTS method were 36.65,19.26 μg·mL-1,respectively.Conclusion The antioxidant activity of β-dione of curcumin was retained through the substitution of the pyrazole ring,and the curcumin pyrazole derivative deserves further investigation as a potential antioxidant.

Human brain banks use a standardized protocol to collect,process and store post-mortem human brains and related tissues,along with relevant clinical information,and to provide the tissue samples and data as a resource to foster neuroscience research according to a standardized operating protocols(SOP).Human brain bank serves as the foundation for neuroscience research and the diagnosis of neurological disorders,highlighting the crucial rule of ensuring the consistency of standardized quality for brain tissue samples.The first version of SOP in 2017 was published by the China Human Brain Bank Consortium.As members increases from different regions in China,a revised SOP was drafted by experts from the China Human Brain Bank Consortium to meet the growing demands for neuroscience research.The revised SOP places a strong emphasis on ethical standards,incorporates neuropathological evaluation of brain regions,and provides clarity on spinal cord sampling and pathological assessment.Notable enhancements in this updated version of the SOP include reinforced ethical guidelines,inclusion of matching controls in recruitment,and expansion of brain regions to be sampled for neuropathological evaluation.

Purpose/Significance To investigate the effectiveness of experiential teaching in perinatal healthcare management contin-uing education.Method/Process The perinatal healthcare team of Peking Union Medical College Hospital holds a four-day experiential learning program for 30 maternity-related medical staffs from China.Through the self-administered experiential teaching questionnaire(ETQ)and satisfaction questionnaire,the researchers analyze the participants'post-teaching skill acquisition,clinical application abil-ity and educational needs,as well as their satisfaction with course content,course duration,teaching design,classroom atmosphere,and teaching format,which are quantified with Likert scale.Result/Conclusion The experiential teaching mode shows good teaching effects in perinatal healthcare management continuing education,and has higher application value.In the future,the researchers should combine it with theoretical teaching and carry out more comprehensive and structured periodic learning classes throughout the country,so as to im-prove both the theoretical foundation and practical ability of healthcare workers for better healthcare services for pregnant women.

Objective To investigate the effect of varying ureteral wall thickness(UWT)at the site of ureteral stones on the clinical efficacy of ureteroscopic lithotripsy(URL).Methods The clinical data of 164 patients with ureteral stones in our hospital were retrospectively analyzed.According to different UWT,the patients were divided into the mild thickening group(84 cases,UWT<3.16 mm),the moderate thickening group(31 cases,UWT 3.16 to 3.49 mm),and the severe thickening group(49 cases,UWT>3.49 mm),and the differences of clinical related indicators among the three groups were compared.Results The incidence of postoperative renal colic and leukocyte disorder in the mild thickening group and the moderate thickening group were lower than those in the severe thickening group,and the differences were statistically significant(P<0.05).The postoperative catheterization time in the mild thickening group and the moderate thickening group were shorter than that in the severe thickening group,and the incidences of secondary lithotripsy,residual stones and stone return to kidney in the mild thickening group and the moderate thickening group were lower than those in the severe thickening group,with statistically significant differences(P<0.05).The length of hospital stay and hospitalization cost in the mild thickening group and the moderate thickening group were shorter/less than those in the severe thickening group,with statistically significant differences(P<0.05).Conclusion With the increase of UWT(especially when UWT>3.49 mm),the incidence of postoperative complications and hospitalization cost of URL increase to varying degrees,and the surgical efficacy decreases.In clinical work,UWT measurement holds potential value in predicting the surgical efficacy and complications of URL.

Objective To evaluate the perioperative safety and feasibility of day-case transurethral holmium laser enucleation of prostate(HoLEP)under over-night mode.Method From January 2021 to March 2023,83 patients of benign prostatic hyperplasia(BPH)were elected and treated with HoLEP by the one surgeon.According to different management methods,these patients were divided into the over-night day-case HoLEP group and the ordinary HoLEP group.Again,these patients were divided into large volume(≥50 mL)group and small volume(<50 mL)group according to the prostate volume.Record the age and perioperative data of all patients[total prostate volume,prostate resection weight,proportion of prostate resection,operating time,changes in peripheral venous blood hemoglobin(Hb),bladder flushing duration,catheter insertion duration,and success rate of first tube removal],the parameters of each group were compared.Result All of the 83 patients undergoing HoLEP surgery in this study,and there were no cases of HoLEP related reoperation or readmission.Among them,there were 43 cases in the over-night HoLEP group,aged 57～90 with an average of(70.1±7.3)years old,and the prostate volume was 29～161 mL with an average of(63.0±28.8)mL,All of them were discharged within 24 h,and there were no cases transferred to the ordinary HoLEP group,the success rate of first tube removal was 88.4%(38/43),and with average catheterization duration was(17.8±3.6)h;The other 40 cases were included into the ordinary HoLEP group,aged 55～87 with an average of(70.4±8.2)years old,the volume of the prostate was 22～118 mL with an average of(59.4±29.0)mL,the success rate of first tube removal was 90.0%(36/40),and with average catheterization duration was(77.5±25.1)h;There was no statistically significant difference in the perioperative parameters(total prostate volume,prostate resection weight,proportion of prostate resection,operating time,changes in peripheral venous blood Hb,and bladder flushing time)between the two groups(P>0.05),while the difference in catheter duration was statistically significant(P<0.01).Conclusion Regardless of the size of the prostate volume,day-case HoLEP is safe and feasible.Day-case HoLEP under the over-night mode is suitable for widespread and routine implementation in China,especially in medical centers with rich experience of HoLEP.