OBJECTIVE To evaluate the value of matrix-assisted laser desorption ionization time-of-flight-mass spectrometry(MALDI-TOF MS)in direct identification of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae positive for blood culture.METHODS The blood culture bottles that were positive for E.coli or K.pneumoniae were collected from the patients with bloodstream infection who were treated in Zhongshan Hospi-tal,Fudan University from Jul.2021 to Jun.2023.The isolates were collected by using a gel-contact clotting tube,then the tested strains were respectively mixed with 4 μg/ml of imipenem,4 μg/ml of meropenem and 2 μg/ml of ertapenem for coculture and were incubated at 35 ℃ for 4 and 5 hours,finally,the strains were i-dentified by using the mass spectrum.The minimum inhibitory concentrations(MICs)of the three types of drugs were tested by microbroth dilution method and were set as the golden standards for the test.RESULTS Totally 31 strains of E.coli and 28 strains of K.pneumoniae that were positive in blood culture bottles were collected,both of the effective rates of controlled growth of the E.coli strains were 100.00％after the incuba-tion for 4 and 5 hours,and the effective rates of controlled growth of the K.pneumoniae strains were 9 6.43％and 100.00％after the incubation for 4 and hours,respectively.The sensitivity,specificity,positive predictive value and negative predictive value of the K.pneumoniae strains against the three types of drugs were 100.00％after the incubation for 5 hours.The specificity and positive predictive value of the E.coli strains against imipenem,meropenem and ertapenem were 100.00％after the incubation for 5 hours;the sensitivities were 73.58％,78.93％and 78.93％,respectively;the negative predictive values were 70.60％,75.00％and 75.00％,respectively.CONCLUSIONS MALDI-TOF MS is rapid and accurate for direct identification of the carbapenem-resistant E.coli and K.pneumoniae strains positive in blood culture bottles,and the accuracy reaches at 100.00％for the test of drug-resistant K.pneumoniae strains after the incubation for 5 hours.The method may provide evidence for clinical treatment of bloodstream infections induced by carbapenem-resistant Enterobacteriaceae.

Objective To evaluate the impact of setting a 4-day incubation time on the detection performance of bloodstream infection(BSI)pathogens by the BacTALERT VIRTUO blood culture system(VIRTUO).Methods Retrospectively collecting blood culture(BC)results from Zhongshan Hospital,Fudan University,from June 2021 to December 2023,and comparing the time-to-detection for clinically significant microorganisms.Results A total of 87 052 BC bottles were collected,of which 7 167(8.23%)were positive.95%of aerobic and anaerobic bottles were reported positive at 65.67 h and 91.2 h respectively.The average(median)time-to-detection for Staphylococcus aureus(S.aureus)was 21.76(16.08)h,Klebsiella pneumoniae(KP)was 15.32(11.65)h,Escherichia coli(E.coli)was 16.14(10.87)h,and Candida species was 35.2(28.5)h.Only 213 bottles(0.24%)were reported positive after 4 days of incubation;among them,88 bottles(41.31%)cultured Propionibacterium acnes(P.acnse).Medical chart reviews for BC reported positive after 96 h(4 days)showed no clinical significance.Simulated growth experiments were conducted on 11 fastidious bacteria,and the median detection time was only 10.8 h,indicating that an incubation time of 4 days is sufficient for fastidious bacteria.Conclusion A 4-day incubation is adequate for VIRTUO system.Reporting 1 day earlier to the doctors can reduce the positive rate of contaminants and the use of antimicrobial agents.

Objective To evaluate the impact of setting a 4-day incubation time on the detection performance of bloodstream infection(BSI)pathogens by the BacTALERT VIRTUO blood culture system(VIRTUO).Methods Retrospectively collecting blood culture(BC)results from Zhongshan Hospital,Fudan University,from June 2021 to December 2023,and comparing the time-to-detection for clinically significant microorganisms.Results A total of 87 052 BC bottles were collected,of which 7 167(8.23%)were positive.95%of aerobic and anaerobic bottles were reported positive at 65.67 h and 91.2 h respectively.The average(median)time-to-detection for Staphylococcus aureus(S.aureus)was 21.76(16.08)h,Klebsiella pneumoniae(KP)was 15.32(11.65)h,Escherichia coli(E.coli)was 16.14(10.87)h,and Candida species was 35.2(28.5)h.Only 213 bottles(0.24%)were reported positive after 4 days of incubation;among them,88 bottles(41.31%)cultured Propionibacterium acnes(P.acnse).Medical chart reviews for BC reported positive after 96 h(4 days)showed no clinical significance.Simulated growth experiments were conducted on 11 fastidious bacteria,and the median detection time was only 10.8 h,indicating that an incubation time of 4 days is sufficient for fastidious bacteria.Conclusion A 4-day incubation is adequate for VIRTUO system.Reporting 1 day earlier to the doctors can reduce the positive rate of contaminants and the use of antimicrobial agents.

OBJECTIVE To evaluate the value of matrix-assisted laser desorption ionization time-of-flight-mass spectrometry(MALDI-TOF MS)in direct identification of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae positive for blood culture.METHODS The blood culture bottles that were positive for E.coli or K.pneumoniae were collected from the patients with bloodstream infection who were treated in Zhongshan Hospi-tal,Fudan University from Jul.2021 to Jun.2023.The isolates were collected by using a gel-contact clotting tube,then the tested strains were respectively mixed with 4 μg/ml of imipenem,4 μg/ml of meropenem and 2 μg/ml of ertapenem for coculture and were incubated at 35 ℃ for 4 and 5 hours,finally,the strains were i-dentified by using the mass spectrum.The minimum inhibitory concentrations(MICs)of the three types of drugs were tested by microbroth dilution method and were set as the golden standards for the test.RESULTS Totally 31 strains of E.coli and 28 strains of K.pneumoniae that were positive in blood culture bottles were collected,both of the effective rates of controlled growth of the E.coli strains were 100.00％after the incuba-tion for 4 and 5 hours,and the effective rates of controlled growth of the K.pneumoniae strains were 9 6.43％and 100.00％after the incubation for 4 and hours,respectively.The sensitivity,specificity,positive predictive value and negative predictive value of the K.pneumoniae strains against the three types of drugs were 100.00％after the incubation for 5 hours.The specificity and positive predictive value of the E.coli strains against imipenem,meropenem and ertapenem were 100.00％after the incubation for 5 hours;the sensitivities were 73.58％,78.93％and 78.93％,respectively;the negative predictive values were 70.60％,75.00％and 75.00％,respectively.CONCLUSIONS MALDI-TOF MS is rapid and accurate for direct identification of the carbapenem-resistant E.coli and K.pneumoniae strains positive in blood culture bottles,and the accuracy reaches at 100.00％for the test of drug-resistant K.pneumoniae strains after the incubation for 5 hours.The method may provide evidence for clinical treatment of bloodstream infections induced by carbapenem-resistant Enterobacteriaceae.

OBJECTIVE：To establish the method for content determination of 6 active ingredients in Paeonia lactiflora during different harvest periods ，and to investigate its variation rules so as to determine the optimal harvesting period. METHODS ：HPLC method was adopted to determine the contents of gallic acid ， catechin， alibiflorin， paeoniflorin， benzoic acid and benzoylpaeoniflorin，and principal component analysis was conducted . The determination was performed on Thermo C 18 column with mobile phase consisted of acetonitrile- 0.1％ phosphoric acid aqueous solution （gradient elution ）at the flow rate of 1.0 mL/min. The detection wavelength was 230 nm，and column temperature was 35 ℃. The sample size was 10 µL. RESULTS ：The linear range of the above 6 ingredients were 0.013 2-0.25 mg/mL（r＝0.999 2），0.013 2-0.25 mg/mL（r＝0.999 9），0.026 8-0.51 mg/mL（r＝0.999 7）， 0.42-8.01 mg/mL（r＝0.999 2），0.016-0.31 mg/mL（r＝0.999 4），0.02-0.38 mg/mL（r＝0.999 8），respectively. The limits of quantification were 0.009 3，0.008 5，0.016 3，0.021 7，0.011 3，0.017 4 mg/mL，and the limits of detection were 0.003 3，0.002 7， 0.005 4，0.007 3，0.003 8，0.005 9 mg/mL. RSDs of precision ，stability and repeatability tests were less than 2％. The recoveries were 96.01％-99.43％（RSD＝1.23％，n＝9），97.95％-100.45％（RSD＝0.79％，n＝9），97.98％-100.11％（RSD＝0.68％，n＝ 9），98.83％ -100.09％ （RSD＝0.65％ ，n＝9），98.58％ - 100.95％（RSD＝1.35％，n＝9），96.28％-103.26％（RSD＝ 1.76％，n＝9）. The contents of above 6 ingredients in Radix Paeoniae Rubra （roots） were 0.016％ -0.057％ ，0-0.067％ ， 0.207％-0.640％，2.350％-5.887％，0.030％- 0.245％，0.054％- 0.381％，respectively. On May 30th，the drying rate of Radix 0451-87266873。E-mail：wangzhen_yue@163.com Paeoniae Rubra was the lowest （about 33％），and on Sept. 15th，the drying rate was the highest （about 49％）. The contents of gallic acid and paeoniflorin in the leaves of P. lactiflora were higher than the root during Jul.-Oct. Results of principal component analysis showed that the variance contribution rates of the first two principal components were 71.845％ and 18.170％，respectively；cumulative variance contribution rate was 90.015％. The months with higher comprehensive scores were May to Jun. and Sept. to Oct. CONCLUSIONS ：Established method is simple ， accurate，reproducible and precise. It can be used to determine the contents of 6 active ingredients in Radix Paeoniae Rubra during different harvest periods. Sept. 30th to Oct. 15th is the optimum harvesting periods for Radix Paeoniae Rubra ，and leaves can be harvested around Jul. 15th.

Objective: To understand physical fitness among students aged 13-18 years in Henan Province and its influencing factors. Methods: Data of 21 785 students aged 13-18 years who participated in the national physical fitness surveys in Henan Province in 2014 were analyzed based on phyical fitness indicators and the questionnarie of physical exercise. The qualified rates of physical fitness indicators were evaluated based on the "National Students Constitutional Health Standards"(2014 revised edition). Results: In 2014, the eligible rate for physical test was 85.6% for boys and 82.5% for girls. Higher eligible rate was observed among boys with sleep duration less than 7 hours, compared to those with higher than 7 hours, while lower eligible rate was more likely observed in boys who reported sweaty and tired in PE class(OR=0.76), sweay and extreme tired in PE class(OR=0.72). Higher eligible rate was more common among girls who attended exercise during recess 2-3 times per day (OR=1.18) compared to those attended exercises higher than 3 times per day. Lower eligible rate was more common among girls with sleep duration less than 7 hours (OR=0.88) and those with low attendance in school recess exercises(OR=0.77). Normal weight, living in urban area, sufficient and regular PE class, daily physical exercise for more than 1 hour, enjoying physical exercise and extracurricular sports activities or long-distance running activities have higher success rates(P<0.05). Conclusion There is a relatively high eligible rate of phyical fitness among middle school boys and girls in Henan Province. Physical fitness is related to multiple factors. These findings highlight the need to target physical fitness interventions with sufficient time allocation in PE class and physical activity so as to effectively promote the phyical quality of students.

OBJECTIVE： To establish a determination method for content of polysaccharide in Acanthopanax senticosus， and to conduct cluster analysis and ultrasonic extraction technology optimization. METHODS： The content of polysaccharide in A. senticosus was determined by phenol-sulfuric acid method. Cluster analysis was conducted by using SPSS 23.0 software of the polysaccharide in A. senticosus from 17 habitats. The ultrasonic extraction technology was optimized with L9（34）orthogonal test using extraction temperature， the ratio of material to liquid， extraction time as factors， the content of polysaccharides as index， and then validated. RESULTS： The linear range of glucose ranged from 0.007 75 to 0.151 mg/mL （r＝0.999 1）； the limits of quantification and detection were 2.854， 0.856 μg/mL； RSDs of precision， stability， and repeatability tests were less than 2％； recovery rates of the sample were 98.41％-101.58％（RSD＝1.23％，n＝6）. Cluster analysis results showed that 17 batches of samples could be clustered into three classes； S1， S6， S10， S12 and S13 were clustered into one class； S3-S5 and S7 were clustered into one class； and the rest samples were clustered into one class. The optimal ultrasonic extraction technology was extraction temperature 55 ℃， ratio of material to liquid 1 ∶ 10 （g/mL）， extraction time 35 min. Results of validation tests showed the content of the polysaccharide under the best process condition was 4.36％（RSD＝0.920％，n＝3）. CONCLUSIONS： Established method is simple，reproducible and suitable for determination of polysaccharide in A. senticosus； the optimized ultrasonic extraction technology is stable and feasible.

Objective To explore the effect of different pH values on calcification of rat vascular smooth muscle cells (VSMCs) through bone morphogenetic protein (BMP)-2 signaling pathway. Methods Healthy male SD rats aged 5-8 weeks were selected in the study. VSMCs from rat thoracic aorta were cultured in vitro, and then identified by immunocytochemistry. The VSMCs were randomly divided into 4 groups by random sampling method:normal group (pH 7.4), pH7.4+high phosphorus group, pH 7.1+high phosphorus group, and pH 7.7+high phosphorus group. Calcium deposition and alkaline phosphatase (AKP) activity were measured by alizarin red staining and enzyme linked immunosorbent assay. The expressions of BMP-2, Smad1 and Runx2 mRNA were detected by RT-PCR. Results Compared with the control group, the calcification staining was increased in pH 7.4+high phosphorus group, calcium content was increased and expressions of BMP-2, Smad1, Runx2 mRNA and AKP activity were also increased (P<0.05). While compared with the pH 7.4+high phosphorus group, calcification staining, calcium content, expressions of BMP-2, Smad1, Runx2 mRNA and AKP activity were decreased in pH 7.1+high phosphorus group (P<0.05). The calcification staining, calcium content, expressions of BMP-2, Smad1, Runx2 mRNA and AKP activity were increased in pH 7.7+high phosphorus group (P<0.05). Conclusion The extracellular acidic environment (pH 7.1) can inhibit high-phosphotus-induced VSMCs calcification, whereas extracellular alkaline environment (pH 7.7) induce high-phosphotus-induced VSMCs calcification. The mechanism is presumably that VSMCs calcification is induced by influencing BMP-2 pathway, which may be mediated by VSMCs phenotype transdifferentiation of BMP-2 signaling pathway.

The numerous noxious reactions caused by misusing medicinal plant ingredients have been widely concerned at home and abroad. The problems of safe drug use needed to be solved. DNA barcode is a powerful molecular identification method, which can cover the shortage of tradditional morphological and chemical identification. In recent years, DNA barcode provided new aspects for the identification of Chinese herbal medicines and have obtained outstanding achievement. Several popular DNA regions ( ITS, ITS2, ps-bA-trnH, rbcL and matK) have been used for the identification of Chinese herbs.

BACKGROUNDThe mitochondrial displacement loop (D-loop) accumulates mutations and single nucleotide polymorphisms (SNPs) at a higher frequency than other regions of mitochondrial DNA (mtDNA). We previously identified disease risk-associated SNPs in the D-loop of chronic kidney disease (CKD) patients; in this study, we investigated the association of age-at-onset and D-loop SNPs in CKD patients.

METHODSThe D-loop region of mtDNA was sequenced in 119 CKD patients attending the Fourth Hospital of Hebei Medical University between 2002 and 2008. The age-at-onset curve of the CKD patients was calculated using the Kaplan-Meier method at each SNP site, and compared using the log-rank test.

RESULTSThe mean age of 119 CKD patients was (55.6±14.2) years, and 56.3% were males. The mean estimated glomerular filtration rate (eGFR) was (81.2±12.4) ml×min(-1)×1.73 m(-2), with 79.8% (n = 95) of patients having an eGFR <60 ml×min(-1)×1.73 m(-2). All participants had an eGFR >30 ml×min(-1)×1.73 m(-2). The age-at-onset for CKD patients who smoked was significantly lower than that of non-smoking CKD patients. The SNP sites of nucleotides 150C/T were identified for their association with age-at-onset using the log-rank test. The age-at-onset of patients with the minor allele T genotype was significantly lower than that of patients with the C genotype at the 150 SNP site (P = 0.010).

CONCLUSIONSGenetic polymorphisms in the D-loop appear to be predictive markers for age-at-onset in CKD patients. Accordingly, the analysis of genetic polymorphisms in the mitochondrial D-loop may help identify CKD patient subgroups at high risk of early onset disease.

Adult ; Aged ; DNA, Mitochondrial ; genetics ; Female ; Humans ; Kaplan-Meier Estimate ; Male ; Middle Aged ; Polymorphism, Single Nucleotide ; genetics ; Renal Insufficiency, Chronic ; genetics