OBJECTIVE To assess the correlation between the steady-state minimal concentration （cmin） and 24 h area under the drug concentration-time curve （AUC24）/minimal inhibitory concentration （MIC） ratio （AUC24/MIC） of vancomycin in pediatric patients， and analyze independent risk factors for treatment failure. METHODS Data of hospitalized children treated with vancomycin and receiving therapeutic drug monitoring in our hospital from January 2021 to July 2024 were retrospectively collected and divided into success group and failure group according to whether the treatment was successful or not. Spearman correlation analysis was used to analyze the correlation between cmin and AUC24/MIC of vancomycin， and one-way and multifactorial Logistic regression analyses were used to screen the independent risk factors for vancomycin treatment failure. RESULTS A total of 59 children were included， with 41 in the success group and 18 in the failure group. Compared with the failure group， AUC24/MIC of vancomycin was significantly higher in the success group （P＝0.038）， but there was no statistically significant difference in the cmin of the two groups （P＞0.05）； cmin of vancomycin was significantly positively correlated with AUC24/MIC （r＝0.499， P＜0.001）， but it has a certain efficacy in predicting the achievement of the AUC24/MIC standard （≥400） （area under the receiver operator characteristic curve＝0.696）， with an optimal cutoff value of 6.05 mg/L determined by the Youden index. The efficacy of AUC24/ MIC in predicting treatment failure was superior to cmin （areas under the receiver operator characteristic curve were 0.671 vs. 0.523， P were 0.038 vs. 0.684）， with higher sensitivity （83.3% vs. 66.7%）. Hypoproteinemia and AUC24/MIC≤369.1 were independent risk factors for vancomycin treatment failure （P＜0.05）. The incidence of nephrotoxicity was 3.4%. CONCLUSIONS There is a significant positive correlation between cmin and AUC24/MIC of vancomycin in pediatric patients； hypoproteinemia and AUC24/MIC≤369.1 are independent risk factors for vancomycin treatment failure in children.

OBJECTIVE To investigate the mechanism of the inhibitory effect of total flavonoids from Taraxacum mongolicum on high-fat diet-induced obesity in mice through modulation of intestinal flora. METHODS Twenty-four C57BL/6J mice were randomly divided into blank group， model group and T. mongolicum total flavonoid group， with 8 mice in each group. Except for the blank group， the other 2 groups were given a high-fat diet， while T. mongolicum total flavonoid group was given T. mongolicum total flavonoid [400 mg/（kg·d）] intragastrically， once a day， for 8 consecutive weeks. During the experiment， the food intake of each group of mice was recorded. After the last medication， the body mass， fat weight， blood lipid level and pathological changes of liver and epididymal fat in mice were evaluated to observe the effect of T. mongolicum total flavonoid on the treatment of obesity in mice. The changes in abundance and structure of intestinal flora in mice were detected by amplicon sequencing； the effects of T. mongolicum total flavonoids on fat metabolism related genes were analyzed by qPCR. RESULTS Compared with model group， the body weight of mice in T. mongolicum total flavonoids group was decreased significantly （P＜0.05）； the levels of total lipid cholesterol， triglycerides， and LDL cholesterol were all decreased significantly （P＜0.01）， and the level of HDL cholesterol was increased significantly （P＜0.01）； the fat indexes of inguinal white adipose tissue and epididymal white wind_lz@hactcm.edu.cn adipose tissue were significantly reduced （P＜0.05）； significant improvement in hepatocellular steatosis and adipose cytopathy were significantly improved； mRNA expressions of COX7A1 and COX8B were significantly upregulated （P＜0.05）. The results of bacterial colony detection showed that compared with the model group， there was a rising trend in the diversity of the bacterial colony in T. mongolicum total flavonoids group， and the Sobs index characterization and β diversity were increased significantly （P＜0.05）. Relative abundances of Blautia， norank_f_Ruminococcaceae， Bilophila， Alistipes， classified_f_Ruminococcaceae， Parabacteroides， norank_f_Desulfovibrionaceae， Anaerotruncus were significantly up-regulated（P＜0.05）， while those of Faecalibaculum， Erysipelatoclostridium， GCA-900066575， Tuzzerella， Lactobacillus， norank_f_norank_o_RF39， achnospiraceae_FCS020_group were significantly down-regulated （P＜0.05）. CONCLUSIONS T. mongolicum total flavonoids can reduce body mass， fat weight and blood lipid levels， and repair the pathological damage to liver and epididymal fat in obese mice， which is related to improving intestinal flora disorders caused by high-fat diet.

Objective To establish a method for simultaneous determination of four high-molecular-weight thiol derivatives (TDs) in workplace air by gas chromatography. Methods The four kinds of vapor-phase macromolecular TDs (1-pentanethiol, 1-hexanethiol, 1-benzyl mercaptan, and n-octanethiol) in the workplace air were collected using the GDH-1 air sampling tubes, desorbed with anhydrous ethanol, separated on a DB-FFAP capillary column, and determined by flame ionization detector. Results The quantitation range of the four TDs was 0.30-207.37 mg/L, with the correlation coefficients greater than 0.999 00. The minimum detection mass concentrations and minimum quantitation mass concentrations were 0.18-0.32 and 0.60-1.05 mg/m³, respectively (both calculated based on the 1.5 L sample and 3.0 mL desorption solvent). The mean desorption efficiencies ranged from 87.07% to 103.59%. The within-run and between-run relative standard deviations were 1.92%-8.22% and 1.89%-8.45%, respectively. The samples can be stored at room temperature or 4 ℃ for three days and up to 7 days at -18 ℃. Conclusion This method is suitable for the simultaneous determination of four vapor-phase TDs in workplace air.

Intestinal tuberculosis (ITB) is a specific infection caused by Mycobacterium tuberculosis invading the intestinal wall, encompassing two types: primary and secondary. In clinical practice, it is more commonly secondary to extrapulmonary tuberculosis, such as cavitary pulmonary tuberculosis. In recent years, the incidence of ITB has shown an increasing trend. Due to its insidious onset and the lack of obvious or specific early symptoms, early diagnosis is challenging, often leading to a prolonged disease course. Therefore, accurate early diagnosis is of great significance for the control and prevention of ITB. Currently, the primary diagnostic methods for tuberculosis include etiological examination, histopathological evaluation, molecular biological diagnosis, and imaging studies. This article summarizes recent advances in the application of these diagnostic techniques for ITB, aiming to provide valuable insights for healthcare professionals.

Objective To explore the treatment of infection after spinal internal fixation.Methods The clinical data of 6 patients with infection after spinal internal fixation in our hospital were analyzed retrospectively.The bacterial culture and drug susceptibility testing were performed to identify the pathogenic bacteria and sensitive antibiotics.Moxifloxacin and/or vancomycin were used empirically for anti-infective therapies first,and then sensitive antibiotics were used according to the results of bacterial culture and drug susceptibility testing.At the same time,imaging examination was performed to determine the infection site and internal fixation,and surgical treatment was decided based on the patients'condition.After operation,the body temperature,inflammatory indexes and drainage of patients were monitored continuously,and the drainage fluid was taken for bacterial culture regularly to evaluate the therapeutic effect.Results The results of bacterial culture in 5 patients were positive and the pathogenic bacteria was staphylococcus aureus,with the susceptibility to vancomycin by susceptibility testing.Among them,1 patient was treated with vancomycin for about 8 weeks because of his advanced age,more basic diseases and high risk of operation;the other 4 patients were received surgery combined with anti-infective treatment with vancomycin for 2 to 4 weeks.One case with negative bacterial culture received surgery combined with anti-infective treatment with imipenem and moxifloxacin.The wound of all patients healed in grade A,the body temperature and inflammatory indexes returned to normal,the low back pain disappeared,and the nerve root symptoms of lower extremities were significantly improved.Conclusion Once the patients with infection after spinal internal fixation are diagnosed,the pathogenic bacterial should be identified as early as possible and sensitive antibiotics should be used.Meanwhile,the internal fixation is removed or re-implanted depending on whether it is infected.

Objective To monitor the antifungal resistance of clinical isolates of Candida spp.in the East China region.Methods MALDI-TOF MS or molecular methods were used to re-identify the strains collected from January 2018 to December 2022.Antifungal susceptibility testing was performed using the broth microdilution method.The susceptibility test results were interpreted according to the breakpoints of 2022 Clinical and Laboratory Standards Institute(CLSI)documents M27 M44s-Ed3 and M57s-Ed4.Results A total of 3 026 strains of Candida were collected,65.33％of which were isolated from sterile body sites,mainly from blood(38.86％)and pleural effusion/ascites(10.21％).The predominant species of Candida were Candida albicans(44.51％),followed by Candida parapsilosis complex(19.46％),Candida tropicalis(13.98％),Candida glabrata(10.34％),and other Candida species(0.79％).Candida albicans showed overall high susceptibility rates to the 10 antifungal drugs tested(the lowest rate being 93.62％).Only 2.97％of the strains showed dose-dependent susceptibility(SDD)to fluconazole.Candida parapsilosis complex had a SDD rate of 2.61％and a resistance rate of 9.42％to fluconazole,and susceptibility rates above 90％to other drugs.Candida glabrata had a SDD rate of 92.01％and a resistance rate of 7.99％to fluconazole,resistance rates of 32.27％and 48.24％to posaconazole and voriconazole non-wild-type strains(NWT),respectively,and susceptibility rates above 90％to other drugs.Candida tropicalis had resistance rates of 29.55％and 26.24％to fluconazole and voriconazole,respectively,resistance rates of 76.60％and 21.99％to posaconazole and echinocandins non-wild-type strains(NWT),and a resistance rate of 2.36％to echinocandins.Conclusions The prevalence and species distribution of Candida spp.in the East China region are consistent with previous domestic and international reports.Candida glabrata exhibits certain degree of resistance to fluconazole,while Candida tropicalis demonstrates higher resistance to triazole drugs.Additionally,echinocandins resistance has emerged in Candida albicans,Candida glabrata,Candida tropicalis,and Candida parapsilosis.

Objective:To systematically evaluate the risk factors for perioperative malnutrition in aged fracture patients.Methods:A comprehensive search of databases including CNKI, WanFang, VIP, SinoMed, Web of Science, Embase, PubMed, and CINAHL was conducted to identify relevant studies on risk factors for perioperative malnutrition in aged fracture patients from inception to May 10, 2023. Additional grey literature was identified by snowball sampling and manual searches. Two postgraduate students trained in evidence-based nursing independently screened the literature, extracted data, and assessed the methodological quality of the studies. Meta-analysis was performed using RevMan 5.4 software.Results:Fourteen original studies were included, covering 46 risk factors for malnutrition. Meta-analysis of factors reported in at least two studies indicated that age≥ 70 years, low body mass index, low hemoglobin, preoperative hypoalbuminemia, female, physical inactivity, non-home residence, low self-care ability, intertrochanteric fracture, chronic obstructive pulmonary disease, chronic gastritis, dementia/cognitive decline, cancer, stroke, chronic heart failure, multiple chronic diseases, high Charlson Comorbidity Index, weight loss, depression, American Society of Anesthesiologists classification≥Ⅲ, taking multiple medications≥ 4 types, and longer hospital stays all increased the incidence of perioperative malnutrition in aged fracture patients ( P< 0.05) . Conclusions:The incidence of perioperative malnutrition in the aged fracture population is high and influenced by multiple factors. This highlights the need for healthcare providers to conduct dynamic and precise nutritional screenings for high-risk patients and to implement personalized perioperative nutritional management to prevent malnutrition and promote rapid recovery in aged fracture patients.

The molecular epidemiological characteristics of 1,4,[5],12:i:-Salmonella in Jiangsu Province were analyzed through whole genome sequencing(WGS).The distribution characteristics of related genes were obtained on the basis of anno-tated drug-resistant genes and plasmid types in the whole genome.Analysis of the molecular epidemiological characteristics of strains with cgMLST revealed possible modes of transmission of quinolone resistance in 1,4,[5],12:i:-Salmonella.Eleven cat-egories of antibiotic resistance genes(ARGs)were annotated among the fluoroquinolone-resistant strains.The detection rate of aminoglycoside ARGs was highest(100％).Twelve quinolone-resistant strains(92.3％)carried the IncHI2/IncHI2A plasmid type.PMQR gene analysis of various strains indicated that the strains from the United States and Europe carried six types of PMQR genes,and the detection rate of qnrB19 was highest.The Jiangsu strains carried three PMQR gene types,and the de-tection rate of aac(6')-Ib-cr was highest(11.84％).Analysis of cgMLST loci from different countries/regions revealed three main epidemic clusters.Some isolates from Jiangsu province might have the same evolutionary origin as some isolates from Eu-rope and the United States,and national/regional differences were observed in the PMQR gene carriage level.

Objective:To prepare mesenchymal stem cells with antioxidant capacity (AO-MSC ) from human umbilical cords and evaluate its cell biological properties.Methods:In control group,mesenchymal stem cells (MSC) were isolated by digesting human umbilical cord Wharton's Jelly tissues with 0.2％ collagenase Ⅱ,and the released cells were collected and cultured in an animal serum-free culture medium.In AO-MSC group,incompletely collagenase Ⅱ-digested tissue debris were allowed to adhere to flusk flat bottoms and the AO-MSC was harvested by adherent culture. The conventional digestion and culture method was used as control.MSC colony forming ability was evaluated by fibroblast colony forming assay (CFU-F).MSC proliferative capacity was evaluated by CCK-8 assay.The MSC surface markers were detected by using flow cytometry and immunofluorescence staining.The adipogenic and osteogenic capacity of MSC was evaluated by multi-differentiation in vitro,and the mRNA expression of genes that control adipogenic and osteogenic differentiation was detected by real-time fluorescence quantitative PCR (RT-qPCR );Moreover,the mRNA expression of antioxidant substances such as SOD-1,GSH,GAT,and NQO1 in MSC was also evaluated by RT-qPCR.Results:The AO-MSC isolated by this strategy reached a confluence of 80％-90％ at around 18 days and grew in a swirling pattern.Flow cytometry and immunofluorescence staining assays showed that CD73,CD29,CD105,CD90 were highly expressed and CD31,CD45,HLA-DR were scarcely expressed in AO-MSC.AO-MSC exhibited stronger self-renewal and differentiation ability compared to MSC.However,the in vitro adipogenic-osteogenic capacity of MSC in the control group was stronger than that of AO-MSC.RT-qPCR assay showed that AO-MSC expressed higher mRNA levels of antioxidant substances compared to MSC.Conclusion:Human AO-MSC is successfully prepared from human umbilical cord without animal serum.

AIM To optimize the extraction process for uracil,hypoxanthine,xanthine,uridine,thymine,inosine,guanosine and 2'-deoxyguanosine from Pheretima guillelmi(Michaelsen),and to determine their contents.METHODS With solid-liquid ratio,ultrasonic time and ultrasonic temperature as influencing factors,contents of hypoxanthine and total nucleosides as evaluation indices,the extraction process was optimized by orthogonal test.HPLC was adopted in the content determination of varioud nucleosides,the analysis was performed on a 30℃thermostatic Agilent C18 column(4.6 mm×250 mm,5 μm),with the mobile phase comprising of methanol-water flowing at 1 mL/min in a gradient elution manner,and the detection wavelength was set at 260 nm.RESULTS The optimal conditions were determined to be 1∶250 for solid-liquid ratio,60 min for ultrasonic time,and 60℃for ultrasonic temperature.Eight nucleosides showed good linear relationships within their own ranges(R2＞0.999 0),whose average recoveries were 99.11%-103.27%with the RSDs of 0.85%-2.89%.CONCLUSION This stable and reliable method can be used for the extraction and content determination of nucleosides from P.guillelmi.