Objective:To treat the Crohn's disease(CD)patients with ustekinumab(UST),to eva-luate their clinical and endoscopic remission,and to evaluate their transmural response(TR)and trans-mural healing(TH)condition using intestinal ultrasonography(IUS).Methods:Retrospective analysis was made on patients diagnosed with CD in Peking University People's Hospital from January 2020 to Au-gust 2022,who were treated with UST for remission induction and maintenance therapy.All the patients were evaluated on both week 8 and week 16/20 after treatment,including clinical,biochemical indica-tors,colonoscopy and IUS examination.Results:A total of 13 patients were enrolled in this study,inclu-ding 11 males and 2 females.The minimum age was 23 years,the maximum age was 73 years and the mean age was 36.92 years.All the patients were in the active stage of disease before treatment,and the average Best Crohn's disease activity index(Best CDAI)score was 270.12±105.55.In week 8,the Best CDAI score of the patients decreased from 270.12±105.55 to 133.16±48.66(t=4.977,P＜0.001).Eight patients achieved clinical remission while 5 patients remained in the active stage.Nine patients underwent colonoscopy evaluation.The average simple endoscopic score for Crohn's disease(SES-CD)score decreased from 10.71±7.14 before treatment to 6.00±7.81(t=2.483,P=0.048)in week 16/20.Four patients achieved endoscopic remission while 5 patients did not.In week 8,5 pa-tients achieved TR,2 patients achieved TH,the other 6 patients did not get TR or TH.In week 16/20,6 patients achieved TR,3 patients achieved TH while the other 4 patients did not get TR or TH.There was no significant statistical difference in the TR effect of UST between small intestine and colon lesions(Fisher test,P＞0.999).The rate of UST transmural response in the patients who had had previous bio-logical agent therapy was lower than those with no previous biological agent therapy,but there was no sig-nificant statistical difference(Fisher test,P=0.491).Conclusion:After treatment of UST,the clinical and endoscopic conditions of the CD patients had been improved,and some patients could achieve clini-cal remission and endoscopic remission.UST had good TR and TH effects on CD.TR might appear in week 8,and the TR effect increased in week 16/20.There was no significant statistical difference in the TR effect between small intestine and colon lesions.TR effect of UST was better in the patients who had no previous biological agent therapy than those who had had other biological agents,but the result had no significant statistical difference.

Objective To investigate the toxicokinetic differences of 3,4-methylenedioxy-N-methylamphetamine(MDMA)and its metabolite 4,5-methylene dioxy amphetamine(MDA)in rats af-ter single and continuous administration of MDMA,providing reference data for the forensic identifica-tion of MDMA.Methods A total of 24 rats in the single administration group were randomly divided into 5,10 and 20 mg/kg experimental groups and the control group,with 6 rats in each group.The ex-perimental group was given intraperitoneal injection of MDMA,and the control group was given intraperi-toneal injection of the same volume of normal saline as the experimental group.The amount of 0.5 mL blood was collected from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.In the continuous administration group,24 rats were randomly divided into the experi-mental group(18 rats)and the control group(6 rats).The experimental group was given MDMA 7 d by continuous intraperitoneal injection in increments of 5,7,9,11,13,15,17 mg/kg per day,respectively,while the control group was given the same volume of normal saline as the experimental group by in-traperitoneal injection.On the eighth day,the experimental rats were randomly divided into 5,10 and 20 mg/kg dose groups,with 6 rats in each group.MDMA was injected intraperitoneally,and the con-trol group was injected intraperitoneally with the same volume of normal saline as the experimental group.On the eighth day,0.5 mL of blood was taken from the medial canthus 5 min,30 min,1 h,1.5 h,2 h,4 h,6 h,8 h,10 h,12 h after administration.Liquid chromatography-triple quadrupole tandem mass spectrometry was used to detect MDMA and MDA levels,and statistical software was employed for data analysis.Results In the single-administration group,peak concentrations of MDMA and MDA were reached at 5 min and 1 h after administration,respectively,with the largest detection time limit of 12 h.In the continuous administration group,peak concentrations were reached at 30 min and 1.5 h af-ter administration,respectively,with the largest detection time limit of 10 h.Nonlinear fitting equations for the concentration ratio of MDMA and MDA in plasma and administration time in the single-administration group and continuous administration group were as follows:T=10.362C-1.183,R2=0.974 6;T=7.397 3C-0.694,R2=0.961 5(T:injection time;C:concentration ratio of MDMA to MDA in plasma).Conclusions The toxicokinetic data of MDMA and its metabolite MDA in rats,obtained through single and continuous administration,including peak concentration,peak time,detection time limit,and the relationship between concentration ratio and administration time,provide a theoretical and data foundation for relevant forensic identification.

BACKGROUND:Satellite cells are myogenic stem cells located between the muscle fiber membrane and the basement membrane.However,a comprehensive review of the aging mechanisms of satellite cells and their potential mitigation strategies is still lacking.This gap in knowledge hinders the effective guidance for current strategies aimed at attenuating skeletal muscle aging. OBJECTIVE:To review the mechanisms of satellite cell aging in skeletal muscle and the relevant strategies for mitigating this aging process. METHODS:Major databases were searched up to May 2023,including Web of Science,PubMed,China National Knowledge Infrastructure(CNKI),WanFang Data,and VIP.Chinese and English search terms included"skeletal muscle,satellite cells,aging,mechanism,and solution strategy".After strict inclusion and exclusion criteria were applied,78 articles were finally included. RESULTS AND CONCLUSION:(1)Satellite cells,situated between the muscle fiber membrane and basement membrane,possess proliferative and differentiative potential.They usually remain in a quiescent state but become activated in response to muscle tissue stimuli,participating in processes of repair and restoration of normal tissue structure.Aging leads to a reduction in satellite cell numbers,resulting in symptoms such as muscle weakness and decreased endurance.(2)Mechanisms of satellite cell aging primarily involve diminished regenerative capacity,perturbed niche interactions with changing ecology,age-dependent loss,and heterogeneity changes.Reduced satellite cell numbers and activity due to aging lead to slower muscle regeneration and increased injury recovery time.Errors during differentiation may occur,resulting in decreased muscle quality and function deterioration.(3)Strategies for mitigating satellite cell aging encompass modulation of the receptor environment of intra-body satellite cells,peripheral interventions to promote satellite cell regeneration,construction of human muscle models,and exercise and nutritional interventions to induce satellite cell proliferation.These strategies hold promise in offering novel insights and methods for satellite cell regeneration and treatment of skeletal muscle diseases.(4)Future research should delve into the mechanisms of satellite cell aging,explore the interaction between satellite cells and their niches,investigate the relationship of satellite cells with the immune system and mitochondrial function,and develop human muscle models to enhance research depth and accuracy.

In recent years,new degradable materials have been applied to cardiovascular implants.Cardiovascular implants with different physicochemical properties and degradation properties have special endpoints for their biological evaluation.In this study,the end points of biological evaluation of degradable cardiovascular implants were reviewed by taking vascular stents and occluders as examples.

Urothelial carcinoma (UC) is one of the most common malignant tumors. The development of omics technologies has provided new perspectives for the diagnosis and treatment of UC. Genomics, transcriptomics, and proteomics have unveiled the molecular mechanisms and biological characteristics of UC, which are conducive to the discovery of new therapeutic targets and biomarkers. Single-cell omics and spatial transcriptomics have further deepened the understanding of cellular heterogeneity and the tumor microenvironment. These technologies show great potential in molecular typing, non-invasive diagnosis, early screening, and personalized treatment of UC. This article, in response to the national key strategy, will delve into how omics technologies can drive new developments in the diagnosis and treatment of UC, as well as the application and translation prospects of these technologies in UC.

Grooming,as an evolutionarily conserved repetitive behavior,is common in various animals,including humans,and serves essential functions including,but not limited to,hygiene maintenance,thermoregulation,de-arousal,stress reduction,and social behaviors.In rodents,grooming involves a patterned and sequenced structure,known as the syntactic chain with four phases that comprise repeated stereotyped movements happening in a cephalocaudal progression style,beginning from the nose to the face,to the head,and finally ending with body licking.The context-dependent occurrence of grooming behavior indicates its adaptive significance.This review briefly summarizes the neural substrates responsible for rodent grooming behavior and explores its relevance in rodent models of neuropsychiatric disorders and neurodegenerative diseases with aberrant grooming phenotypes.We further emphasize the utility of rodent grooming as a reliable measure of repetitive behavior in neuropsychiatric models,holding promise for translational psychiatry.Herein,we mainly focus on rodent self-grooming.Allogrooming(grooming being applied on one animal by its conspecifics via licking or carefully nibbling)and heterogrooming(a form of grooming behavior directing towards another animal,which occurs in other contexts,such as maternal,sexual,aggressive,or social behaviors)are not covered due to space constraints.

Objective To investigate the risk factors for bronchopulmonary dysplasia(BPD)in twin preterm infants with a gestational age of<34 weeks,and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.Methods A retrospective analysis was performed for the twin preterm infants with a gestational age of<34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020.According to their conditions,they were divided into group A(both twins had BPD),group B(only one twin had BPD),and group C(neither twin had BPD).The risk factors for BPD in twin preterm infants were analyzed.Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.Results A total of 904 pairs of twins with a gestational age of<34 weeks were included in this study.The multivariate logistic regression analysis showed that compared with group C,birth weight discordance of>25%between the twins was an independent risk factor for BPD in one of the twins(OR=3.370,95%CI:1.500-7.568,P<0.05),and high gestational age at birth was a protective factor against BPD(P<0.05).The conditional logistic regression analysis of group B showed that small-for-gestational-age(SGA)birth was an independent risk factor for BPD in individual twins(OR=5.017,95%CI:1.040-24.190,P<0.05).Conclusions The development of BPD in twin preterm infants is associated with gestational age,birth weight discordance between the twins,and SGA birth.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Urothelial carcinoma (UC) is one of the most common malignant tumors. The development of omics technologies has provided new perspectives for the diagnosis and treatment of UC. Genomics, transcriptomics, and proteomics have unveiled the molecular mechanisms and biological characteristics of UC, which are conducive to the discovery of new therapeutic targets and biomarkers. Single-cell omics and spatial transcriptomics have further deepened the understanding of cellular heterogeneity and the tumor microenvironment. These technologies show great potential in molecular typing, non-invasive diagnosis, early screening, and personalized treatment of UC. This article, in response to the national key strategy, will delve into how omics technologies can drive new developments in the diagnosis and treatment of UC, as well as the application and translation prospects of these technologies in UC.

Objective:To investigate the effect of genetic polymorphism of MTHFR C677T (rs1801133) on methotrexate (MTX) related toxicity in pediatric mature B-cell lymphoma patients. Methods:Fifty-eight intermediate and high risk patients under 18 years of age with mature B-cell lymphoma who received 5 g/m2 MTX (24 h intravenous infusion) in Sun Yat-sen University Cancer Center from August 2014 to December 2021 were included,and their toxicity of high-dose MTX (HD-MTX) were monitored and analyzed. Results:Among the 58 pediatric patients,the number of CC,CT,and TT genotypes for MTHFR C677T was 33,19 and 6,respectively. A total of 101 courses of HD-MTX therapy were counted,of which plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion were observed in 35 courses,≤0.2 μmol/L in 66 courses. Inter-group comparison showed that plasma MTX level>0.2 μmol/L at 48 h post-MTX infusion increased the risk of developing oral mucositis (P<0.05). Compared with wild-type (CC genotype),patients in the mutant group (CT+TT genotype) were more likely to develop myelosuppression,manifested as anemia,leucopenia,neutropenia and thrombocytopenia. However,plasma MTX level at 48 h was not associated with MTHFR C677T gene polymorphism. Conclusion:The risk of developing oral mucositis in children with mature B-cell lymphoma is associated with plasma MTX concentration. Polymorphism of MTHFR C677T gene is not related to plasma MTX concentration in children with mature B-cell lymphoma,but is related to grade Ⅲ to Ⅳ hematological toxicity.