1.Interference of alkaline phosphatase on clinical cardiac troponin Ⅰ assay
Zejin LIU ; Fang ZHENG ; Zhenlu ZHANG ; Qingkun FAN ; Chun WANG
Chinese Journal of Laboratory Medicine 2010;33(9):831-833
Objective To evaluate the interference of ALP on cTnI assays. Methods One normal mixed plasma sample and 2 abnormal mixed plasma samples with different cTnI levels were prepared, and then divided them into 8 groups respectively. One group was randomly chosen as control while different amounts of ALP were added into the other seven groups. The concentrations of cTnI and ALP in each plasma portion were detected by ACCESS2 (Beckman-Coulter, Inc ) and AXSYM (Abbott Laboratories )separately. The results of the seven tested groups were then compared with those of the control, so as to evaluate whether ALP could interfere with the cTnI assay. Results When the chemiluminescent Access cTnI assay was carried out for detection of normal plasma, the concentration of ALP was up to 3 716 U/L and did not interfere with the test results of cTnI [(0. 04 ±0.01) μg/L] compared with those of the control portion [(0. 04 ± 0. 01 ) μg/L] (t = 0. 40, P > 0. 05 ). Once the concentration of ALP went beyond 917 U/L, the AXSYM cTnI assay results [( 0.08 ± 0. 01 ) μg/L] were higher than those of the normal control ( t =-4. 89, P<0. 01 ); When the concentration of ALP was up to 3 534 U/L, the test results of abnormal plasma cTnI detected by the Access assay [( 13.41 ±0. 17) μg/L] did not show significant differences from those of the control [(13.48±0.16) μg/L] (t=0. 52,P>0.05).Conclusions High concentration ofALP did not interfere with the Access cTnI assay or lead to false positive results. However, the high level of ALP( > 917 U/L) could interfere with the AXSYM cTnI assay and cause a false positive result.
2.Establishment of the 99th percentile of sensitive troponin Ⅰ in apparently healthy Chinese people in Kunming and Wuhan
Zejin LIU ; Zhenlu ZHANG ; Gengsheng ZHAO ; Hui GAO ; Shuzheng CAO ; Xuan SUN
Chinese Journal of Laboratory Medicine 2012;35(10):894-898
Objective To evaluate the performance of Beckman Coulter Enhanced troponin Ⅰ immunoassay system (including the limit of detection and total imprecision) and establish the 99th percentile of Enhanced troponin Ⅰ in apparently healthy Chinese people in Kunming and Wuhan.Methods Evaluated the limit of detection and total imprecision of Beckman Enhanced troponin Ⅰ according to protocols EP of Clinical Laboratory Standards Institute; chose apparently healthy people from Wuhan (average altitude of 27 m) which represents plain regions,and Kunming (average altitude of 1895 m) which represents plateau regions.760 subjects from Wuhan were selected,aging from 30 to 91,included 400 males and 360 females.A total of 192 subjects from Kunming were selected,aging from 30 and 77,60 patients,which included 60 male and 132 female cases.To calculate the 99th percentile of Enhanced troponin Ⅰ by region,age,and gender.Results The limit of detection of Beckman Enhanced troponin Ⅰ is 0.013 μg/L,the cTnI concentration is 0.025 μg/L at 10% CV.The 99th percentile of Enhanced troponin Ⅰ of the total population in Wuhan is 0.036 μg/L,the 99th percentile of men and women are 0.038 μg/L and 0.035 μg/L respectively,the 99th percentile in the 30-69 years group and over 70 years group are 0.038 μg/L and 0.035 μg/L respectively.The 99th percentile of Enhanced troponin Ⅰ of the total population in Kunming is 0.040 μg/L.To keep the 2nd digit after decimal point for results from Wuhan and Kunming,the 99th percentile of Enhanced troponin Ⅰ of the apparently healthy Chinese in 0.04 μg/L,where the CV is 8.23%.The percentage of positive samples detected below the 99th percentile in the normal reference population in Wuhan is 94%.Conclusions The 99th percentile of Beckman Enhanced troponin Ⅰ of the Chinese apparently healthy people is 0.04 μg/L,where the total imprecision is 8.23%,and the detection performance reach the acceptable levels per the guideline.
3.Effects of tanshinone IIA on proliferation, apoptosis and expression of HIF-1α, VEGF and wild-type P53 in human hepatoma HepG2 cells under hypoxia
Lixuan LIU ; Lingfei WU ; Wei DENG ; Xiaotao ZHOU ; Ruipei CHEN ; Mengqi XIANG ; Yitian GUO ; Zejin PU ; Guoping LI
Chinese Journal of Pathophysiology 2014;(12):2155-2160
[ ABSTRACT] AIM:To investigate the effects of tanshinone IIA ( Tan IIA) on proliferation, apoptosis and its mo-lecular mechanism in human hepatoma HepG2 cells under hypoxic condition.METHODS:Hypoxia model was established by treatment with cobalt chloride ( CoCl2 ) .The cells were divided into normoxia control group, hypoxia control group and hypoxia combined at different concentrations of Tan IIA groups.After HepG2 cells were incubated with different concentra-tions of Tan IIA (0.5, 1.0, 2.0, 5.0 and 10.0 mg/L) for 24 h, 48 h and 72 h under hypoxic condition, the cell prolifer-ation was determined by MTT assay.After Tan IIA was added to the media at different concentrations for 24 h and 48 h, the apoptotic cells were observed by Hoechst 33258 staining.The protein levels of hypoxia-inducible factor 1 alpha (HIF-1α) , vascular endothelial growth factor ( VEGF) and wild-type P53 were detected by Western blotting after cultured with different concentrations of Tan IIA for 48 h.RESULTS:Tan IIA inhibited the proliferation of HepG2 cells in a dose-and time-dependent manner.Tan IIA induced the typical morphology of apoptotic cells and increased the apoptotic rate in a dose-and time-dependent manner after treatment with 1.0 mg/L~5.0 mg/L for 24 h and 48 h under hypoxic condition. The protein levels of HIF-1αand VEGF were weakly expressed in HepG2 cells under normoxia but up-regulated after incu-bated under hypoxia for 48 h.The protein expression of HIF-1αand VEGF were decreased with the increase in the concen-tration of Tan IIA under hypoxia.The protein expression of wild-type P53 was increased with the increase in the concentra-tions of Tan IIA under hypoxia.CONCLUSION:Tan IIA significantly inhibits the proliferation and induces the apoptosis of human hepatoma HepG2 cells under hypoxia, which may be related to the down-regulation of HIF-1αand VEGF and up-regulation of wild-type P53.
4.Effect of demethylation on adenosine and homocysteine-induced apoptosis in HepG2 cells
Mengqi XIANG ; Lixuan LIU ; Wei DENG ; Xiaotao ZHOU ; Peirui CHEN ; Yitian GUO ; Yanqing YE ; Zejin PU ; Lingfei WU
Chinese Pharmacological Bulletin 2014;(7):973-978,979
Aim To investigate the mechanism of demethylation on adenosine (ADO )and homocysteine (HCY)-induced apoptosis in human hepatoma HepG2 cells .Methods HepG 2 cells were treated with differ-ent concentrations of ADO (1.0、2.0、4.0 mol · L-1 ) alone or in combination with HCY for 6h,12h and 24h,5-aza-2-deoxycytidine (5-Aza-CdR)as a positive control.Cell viabilities were assessed by CCK8 assay. Cell apoptosis was observed by AnnexinV-FITC/PI staining.The mitochondrial membrane potentials(ΔΨ) were measured by flow cytometry.The mRNA and pro-tein expressions of caspase-3,caspase-8,caspase-9, MDM-2,p53,Cytochrome C,DNMT1,DNMT3a,DN-MT3 b were detected by RT-qPCR and Western blot re-spectively.Results ADO alone or in combination with HCY significantly reduced the viability of HepG2 cells in a dose and time-dependent manner.The apoptotic rates of HepG2 cells after combination treatment with ADO and HCY at 1 .0,2.0,4.0 mol · L-1 for 24 h were (1 8.63 ± 1.25 )%,(29.42 ±2.37 )% and (42.47 ±3.09 )%,compared with the control group (1.30 ±0.82 )%,P <0.01;and the mitochondrial membrane potentials were decreased from 674.15 ± 82.8%(black control group)to (428.38 ±54.5)%, (297.78 ±30.5)%,(74.45 ±5.73)%,P<0.01, respectively.The expressions of caspase-3,caspase-8, caspase-9,MDM-2,p53,Cytochrome C were up-regula-ted and MDM-2 were down-regulated after combination treatment of ADO and HCY.The mRNA expressions of DNMT1 ,DNMT3 a and DNMT3 b were down-regulated after combination treatment with ADO and HCY or 5-Aza-CdR alone.Conclusion Combination treatment of ADO and HCY can cause cellular methylation chan-ges.The effects of demethylation of ADO and HCY may activate p53 gene and mitochondrial pathway, which at last leads to HepG2 cell apoptosis.
5.Screening analysis of flat foot disease among school age children in Kunming City
ZHANG Yingjie, WU Tong, HUANG Jiazheng, ZHANG Zejin, LIU Luyun, XIONG Ying, XIAO Jiayu
Chinese Journal of School Health 2023;44(5):765-768
Objective:
To investigate the prevalence of flat feet and associated factors in school aged children in Kunming City, to provide evidence supporting the prevention of flat feet.
Methods:
From December 2021 to February 2022, 4 444 children aged 7-13 in five primary schools in Kunming were screened for flat feet with the optical foot assessment and recording device. The incidence of flatfoot was counted, and Logistic regression was used to analyze the influencing factors of flatoccurrence.
Results:
The overall prevalence rate was 29.10%, of which 21.79% were mild, 52.43% were moderate, 25.78% were severe, 89.10 % were bipedal, and 10.90% were monopedal. The prevalence rates in the 7-year old and 13-year old groups were 36.91% and 10.43%, respectively, and the risk in the former was 5.00 times that in the latter( OR=5.00, 95%CI =3.22-7.52). The prevalence rates in rural and urban students were 38.53%, 22.46%, respectively, and the risk in the former was 2.17 times that in the latter( OR=2.17, 95%CI =1.90-2.47). The prevalence of flat feet in male and female students were 34.21%, 23.29%, respectively, and the risk in male students was 1.71 times higher than that in female students( OR=1.71, 95%CI =1.50-1.95). The incidence of flat feet correlated with BMI, and the risk of flat feet was higher in the group with overweight and obese groups than normal( OR=1.31, 1.10, P < 0.01).
Conclusion
The prevalence of flat feet in school age children aged 7-13 years decreased with age. The prevalence and risk of flat feet is lower in girls than boys, and the incidence and risk of flat feet are lower in urban than rural children. The incidence of flat feet in most children is moderate, and the risk increased with increasing BMI. For school aged children with flat feet, early prevention, detection and treatment are needed.
6.Evaluation of the analytical performance of AccuTnI+3 assay and establishment of the regional 99th percentile from an apparently healthy Chinese population
Zejin LIU ; Jinsuo KANG ; Xin SHU ; Jia DU ; Jie YANG ; Gengsheng ZHAO ; Yahui LIN ; Kaijuan WANG ; Zhenlu ZHANG
Chinese Journal of Laboratory Medicine 2017;40(12):959-964
Objective To validate the analytical performance of a cardiac troponin I(cTnI)assay AccuTnI+3 on chemiluminescnet analyzer DXI800 and Access2;and to establish the 99th percentile of cTnI in an apparently healthy Chinese population.Methods The subjects are composed of 1 369 apparently healthy people and 20 acute myocardial infarction(AMI)patients from Wuhan Asian Heart Hospital and Fuwai Hospital from October 2014 to June 2015.The healthy people include 680 males and 689 females;with 340 subjects aged 18-30,674 subjects aged 31-64, and 355 subjects aged ≥65.The detection limits and imprecision of AccuTnI +3 assays were validated according to CLSI EP 15-A2 and EP17-A2 documents;the same samples were analyzed on DXI800 and Access2 to assess the consistency between the two analyzers using Bland Altman plot and Passing-Bablok regression.The correlation between different sample types (lithium heparin plasma, EDTA plasma & serum)were assessed using linear regression analysis.The lithium heparin plasmasamples from 1 369 apparently healthy people were analyzed to calculate the 99th percentile of cTnI.The cTnI concentrations were compared among age and sex groups.The 99th percentile of cTnI were also calculated for each group.The detection rate of cTnI in apparently healthy people was calculated using SPSS23.0.Results The limit of blank(LoB), limit of detection(LoD), and limit of quantification(LoQ)where CV%=10% were 0.007 ng/ml,0.010 ng/ml and 0.016 ng/ml on DXI800;0.008 ng/ml,0.012 ng/ml and 0.026 ng/ml on Access2,respectively.The cTnI measurements on DXI800 and Access2 were consistent and comparable.The cTnI concentrations of lithium heparin plasma, EDTA plasma and serum samples were linearly correlated pairwise: EDTA plasma measuremen t =0.76 heparin plasma measurement, R2=0.999(n=40, P<0.001); serum measuremen t =1.05 heparin plasma measurement,R2=0.996(n=40,P<0.001); serum measuremen t=1.38 EDTA plasma measurement, R2=0.993(n=40,P<0.001).The 99th percentiles were 0.030 ng/ml and 0.035 ng/ml on DXI800 and Access2,respectively,from 1 369 apparently healthy Chinese people.cTnI is significantly higher in elder group than in younger group.The 99th percentiles in 18-30 years old group,31-64 years old group,and≥65 years old group are:0.011 ng/ml,0.029 ng/ml,and 0.035 ng/ml respectively for DXI800;0.023 ng/ml,0.034 ng/ml, and 0.045 ng/ml respectively for Access2.cTnI is significantly higher in men than in women.The 99th percentiles in men and women are: 0.034 ng/ml and 0.032 ng/ml respectively for DXI800;0.043 ng/ml and 0.031 ng/ml respectively for Access2.cTnI was measurable in 62%and 87%of healthy subjects on DXI800 and Access2 systems,respectively.Conclusions The analytical performance of AccuTnI+3 assay fulfills the need of clinical use and the criteria of high-sensitive cardiac troponin assay.