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Objective:To compare the consistency and detection capability of seven 2019-nCoV nucleic acid detection kits, and provide reference for detection method selection of clinical laboratory and diagnosis of new coronavirus pneumonia.Methods:Two batches of pharyngeal swab samples were collected from tenpatients with confirmed infection of 2019-nCoV and 10 suspected patients with negative 2019-nCoV test results during January 29 to February 5, 2020 in Shenzhen Luohu People′s Hospital. Seven kinds of kits were labeled as ato g and used for nucleic acid detection respectively to evaluate the consistency of the test results of the clinical samples. A 2019-nCoV positive specimen was selected and diluted to 5-concentration gradient plates (Level-1 to 5) with RNase-free water. The positive detection rate and intra-batch repeatability of different brands of kits were compared.Results:The negative and positive coincidence rates of twenty clinical samples tested by six kinds of kits were 100%, and the positive and negative coincidence rate was 8/10 and 10/10 for the other kit, respectively. The results of intra-batch repeatability showed the CVs of viral loads tested by these seven kits were all less than 5%. In the concentration range of Level-1 to 3, the detection capability for open reading frame (ORF)1ab gene of Kit b,d and f was lower than Kit a,c,e and g, and the detection capability of kit e and g was the highest (14/15). The detection capability for N gene of Kit a (15/15) was higher than the other 5 kits. The comprehensive analysis of the detection capability for ORF1ab and N gene showedthat Kit d had the lowest detection capability (ORF1ab:40%,N:53%), and there was no significant difference in the detection capability of Kit a, b, c, e, and f.Conclusions:There was no significant difference in the accuracy and repeatability of the seven kits for positive samples with high viral loads, and the detection performance was good; but some kits had poor detection capability for weak positive samples. It is suggested that the weak positive samples should be rechecked by at least two manufacturers′ kits to ensure the accuracy of the results.
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Objective@#To identify a α-globin gene mutation-IVS-Ⅱ-55 (T→A) and analyze hematological characteristics of IVS-Ⅱ-55 (T→G) carriers. @*Methods@#The peripheral blood samples were collected from the members of five family and three sporadic IVS-Ⅱ-55(T→G) carriers for the analysis of RBC parameters and hemoglobin electrophoresis. Gap-PCR, PCR-RDB (reverse dot blot) and DNA sequencing were carried out for the identification of gene deletion and mutation of α-globin and β-globin. @*Results@#The results of RBC parameters of five infant probands which presented with microcytic hypochromic anemia were below the normal reference interval. One of the adult carriers of IVS-Ⅱ-55 (T→G) heterozygote alone presented with microcytic hypochromic anemia, and the others showed normal RBC parameters. The hematological phenotype index (MCV, MCH and HbA 2 ) of one adult carrying a compound heterozygote for IVS-Ⅱ-55 (T→G) and βCD27-28M/N were 65.0 fL, 20.3 pg and 5.8% respectively. The hematological phenotype index (MCV, MCH, HbA 2 and HbF) of one adult carrying a compound heterozygote for IVS-Ⅱ-55 (T→G) and SEA-HPFH were 81.9 fL, 26.5 pg, 3.0% and 29.0% respectively. The HbA 2 levels of all carriers of IVS-Ⅱ-55 (T→G) heterozygote alone were in normal range. No abnormal hemoglobin band was detectable on hemoglobin electrophoresis for all the carries. @*Conclusion@#The carriers of IVS-Ⅱ-55(T→G) heterozygote alone were asymptomatic. The phenotype of compound heterozygote for β-thalassemia was similar to that of β-thalassemia alone.
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Objective Non-muscle myosin heavy chain ⅡA (NMHC ⅡA ) plays a significant role in tumor progression and metastasis .Our prior study showed that the expression of NMHC ⅡA was much higher in human bladder cancer sample than that in adjacent tissue .The increased level of NM HC ⅡA expression was correlated with worse prognosis .However ,the role of NMHC ⅡA is unknown in the invasion and metastasis of bladder cancer .Methods RT-PCR and western blotting were used to examine NMHC ⅡA expression lev-els in normal bladder epithelial cells and bladder cancer cell lines .T he migration and invasion ability of cells was tested by wound healing assay and Transwell invasion assay ,respectively .Results Our study showed that knockdown of NMHC ⅡA inhibited migration and invasion in bladder cancer cell line .Conclusion The study indicated that NM HC ⅡA expression increased the invasion and metastasis ability of bladder cancer cell line in vitro .
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Objective To estimate the methodology for evaluating the analytical measurement range ( AMR) and the clinically reportable range ( CRR) in lab-developed system in clinical chemistry .Methods Method evaluation .Take serum CK for instance , a series of samples were prepared from both a specimen with a high concentration of the analyte of interest and a specimen with a low concentration for the following assays.Average slope method , linear dilution recovery method and the method recommended by Clinical and Laboratory Standards Institute ( CLSI ) EP6-A were used to established AMR in the lab-developed clinical chemistry system.Based on the maximum valid dilution of the specimen and the results of AMR , CRR were determined.One-half of the total error allowance ( TEa) of Chinese health standard was set up as allowance error (7.5%).Results X-Y scatter plot was made by assigning sample numbers to the horizontal axis and actual measured values to the vertical axis , which determined the upper limit of AMR was approximate 1 651 U/L.The results analyzed by average slope method indicated that the linear correlation between expected values and actual measured values was determined , the correlation (r), the intercept (a) and the slope (b) met the linear standard, and AMR was 5-1 699 U/L.The results analyzed by EP6-A indicated that the best fitting curve was obtained by using cubic polynomial method , and the linearity deviation of the minimum concentration was -77.1%, which exceeded one-half of TEa.Followed by the deletion of the maximum concentration , the resumed experiment was done .The results showed that the nonlinear coefficient c of quadratic polynomial and the nonlinear coefficient c and d of cubic polynomial have no significant difference to 0, and AMR was 7.5-1 458.0 U/L.By linear dilution recovery method , the linear correlation between expected values and actual measured values was determined , the correlation ( r) , the intercept ( a) and the slope ( b) met the linear standard , the recovery rates was between 100.0%and 104.8%, and AMR is 5 -1 699 U/L.The CRR was determined to be 5 -33 880 U/L, which met the standard of TEa . Conclusions Average slope method, linear dilution recovery method and EP 6-A method were all used to established AMR in lab-developed clinical chemistry system .Without complicated statistical analysis , linear dilution recovery method was suitable for clinical use .The linearity deviation of the minimum concentration analyzed by EP6-A did not meet the standard of the quality objective system , suggesting defects in the statistical analysis of the results .CRR was feasibly determined by using linear dilution recovery method align with AMR.
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Objective To investigate the precision, trueness, and accuracy of self-developed detection system in clinical chemistry.Methods This was a methodological evaluation.Take serum creatine kinase( CK) for instance, 6 serum sampleswith different leves ( on the upper or lower limit of the reference range or close to the medicine decide levels ( MDLs) , were collected for within-run precision( repeatability) and within-laboratory precision ( intermediate precision ) experiments.5 proficiency testing ( PT ) samples, 5 samples assigned value by reference method, and 40 fresh-frozen serums were measured and compared with reference method for trueness verification.Drawing method evaluation decision chart, calculating total errors and sigma level evaluation experiment based on the CV, bias, and allowed total errors(TEa)were used to evaluate the accuracy performance.The precision, trueness, and accuracy were compared with the quality indicators.Results The within-run precision and within-laboratory precision were less than the highest requirement of Chinese industrial standard.The mean bias was -8.96%, didn′t reachthe required standard (5.5%).After taking corrective actions, all samples but one ( -5.8%) met the required standard. Compared with the reference method, the mean bias on the MDLs was less than TEa.The performance points of the method evaluation decision chart indicated excellence performance.The total errors on MDLs were 14.2%, 10.4% and 7.6%, less than 15%.The sigma levels on MDLs were 5.9, 7.5 and 15, also achieved excellent level. Conclusions The precision, trueness, and accuracy performance of CK measured by self-developed detection system achieved excellent level of the Chinese industry standard, and the same results were found from different evaluation methods.
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Objective To explore the relationship between glucose-6-phosphate dehydrogenase deficiency and type 2 diabetes and to provide reference for clinical diagnosis,monitoring and treatment of Type 2 diabetes.Methods Subjects were selected from our hospital,including 173 cases of healthy volunteers assigned to the control group;1 95 cases with type 2 diabetes conforming to the diagnostic criteria of WHO were assigned to the diabetic group.97 cases were diagnosed with glucose-6-phosphate dehydrogenase deficiency in our hospital,of whom 82 cases were assigned to simple glucose-6-phosphate dehydrogenase deficiency group,and 1 7 cases were assigned to the diabetes with glucose-6-phosphate dehydrogenase deficiency group.The correlation of glucose-6-phos-phate dehydrogenase activity and diabetes was measured by each detected value.Results Compared with the control group,the glu-cose-6-phosphate dehydrogenase activity and RBC count in diabetic group were higher(P <0.05).Positive correlations between glu-cose-6-phosphate dehydrogenase activity and RBC count in the two groups were significant(P <0.05).HbA1c and FBG showed a significant positive correlation in the control group,diabetic group and diabeties with glucose-6-phosphate dehydrogenase deficiency group(P <0.05).But there was no significant correlation in the glucose-6-phosphate dehydrogenase deficiency group.The rate of screening for glucose-6-phosphate dehydrogenase deficiency in diabetes group was 3.6%,and the rate in the control group was 1. 1%.When HbAlc≥6.5%,the rate of screening for glucose-6-phosphate dehydrogenase deficiency in the diabetes group was signifi-cantly higher than that in the control group (χ2 =4.239,P =0.039).Conclusion The level of HbA1c is discordant with that of blood glucose in diabetic patients with glucose-6-phosphate dehydrogenase deficiency group.Diabetes leads to the increasement of the rate of glucose-6-phosphate dehydrogenase deficiency.The glucose-6-phosphate dehydrogenase activity of diabetic patients with non-glucose-6-phosphate dehydrogenase dificiency is higher than that of the normal group.It may be associated with the level of RBC or increase of compensatory.Further more,glucose-6-phosphate dehydrogenase activity may be a good indicator for controlling diabetes,which remains to be further studied.
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Objective To investigate the interference of hyperlipidemia and hyperbilirubinaemia to HbA1c measurements by ion‐exchange high‐performance liquid chromatography(IE‐HPLC) method .Methods Fresh whole‐blood samples collected with EDTA‐K2 anticoagulant tubes were divided into four groups :control group(HbA1c<6 .2% ) ,diabetes group(HbA1c≥6 .2% ) ,hyperlipi‐demia group(TG 3 -20 mmol/L);hyperbilirubinaemis group (TBIL 21 -549 μmol/L) .HbA1c of these samples were measured with affinity chromatography(AC‐HPLC) and IE‐HPLC respectively .Results When HbA1c≤18 .7% ,r=0 .993 ;95% confidence interval(CI) of HbA1c results by using IE‐HPLC method was -0 .71 -0 .89 ;coefficient of variation was -5 .8% -6 .8% ;P=0 .198 and the difference was not statistically significant .When HbA1c< 16 .3% ,r= 0 .997;95% CI of HbA1c results with IE‐HPLC method is -0 .31-0 .67;coefficient of variation was -5 .8% -4 .3% .P=0 .000 and the difference was statistically signifi‐cant .No interference was detectded with the results ;When HbA1c was 16 .3% -18 .7% ,positive bias was observed with the re‐sults .When TG≤20 .78 mmol/L ,r=0 .995;95% CI of HbA1c results with IE‐HPLC method was -0 .26-0 .50 ;coefficient of var‐iation was -5 .5% -5 .8% .P=0 .000 and the difference was statistically significant .No interference was detectded with the re‐sults;When TBIL≤549 .3 μmol/L ,r=0 .990 ;95% CI of HbA1c results with IE‐HPLC method was -0 .08 -0 .63;coefficient of variation was -14% -4 .1% .P=0 .000 and the difference was statistically significant .When TBIL≤342 .1 μmol/L ,r= 0 .994 ;95% CI of HbA1c results with IE‐HPLC method was -0 .09-0 .50;coefficient of variation was -5 .5% -4 .1% .No interference was detectded with the results .When TBIL was 380 .7-549 .3 μmol/L ,negative bias was observed with the results .Conclusion Our data indicated that HbA1c measurement with IE‐HPLC method could resist the interference of hyperlipidemia;When TBIL≤380 .7 μmol/L and HbA1c<16 .3% ,the results could meet the needs of general clinical detection .Clinical staff should choose more specific HbA1c measurement method according to the patient's condition .
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Since the beginning of clinical use in the 1970s,hemoglobin A1c (HbA1c) has become the standard tool for monitoring glycemic control in patients with diabetes.The role of the HbA1c test was broadened in 2010,when the American Diabetes Association added HbA1c as a diagnostic criterion for diabetes.However,hemoglobin variants,various clinical scenarios and drugs may yield false results that would mislead clinical diagnosis and treatment.
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Objective To evaluate the precision,accuracy,linear range and anti-interference performance of HbA1c assay by u-sing Primus Trinity Ultra2 automated analyzer.Methods According to Document EP published in 2004 by American Clinical and Laboratory Standards Institution(CLSI)and relative literatures,the precision,accuracy,linear range and anti-interference perform-ance were evaluated.Results The within-run and between-run CVs of HbA1c determination were both less than that announced by manufacture.In the tests of samples with certain concentrations,all the results were within the verification range respectively.In the linear verification,regression equation between the theoretical and measured values demonstrated that r2 >0.95,and a value was within the range of 0.97-1.03.For Primus Trinity Ultra2 the limit of interference effect didn′t exceed the allowable error at the medical decision concentrations.Conclusion The precision,accuracy,linear range and anti-interference was evaluated of the Primus Trinity Ultra2 automating HbA1c all could meet the manufacture′s declaim and the clinical needs.
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ObjectiveTo evaluate analytical performance of NT-proBNP on Electro-Chemiluminescence Immunoassay system.MethodsThe precision,accuracy,limit of blank ( LoB ),limit of detection (LoD),functional sensitivity (FS),analytical measure range (AMR),maximal dilution rate,clinical reportable range(CRR) and the analytical anti-interference ability of NT-proBNP were evaluated according to EP documents issued by CLSI and related references.The analytical performance data were compared to quality standards declared by the manusfacturers.According to CLSI C28-A2,80 healthy volunteers,aged from 18 to 74, were chosen and divided into 4 groups on average for biological reference intervals verification.Results The within-run CV and total CV were 1.1％ -2.2％and 1.5％ -2.9％ respectively.The deviations from controls distributed by National Center for Clinical Laboratory and affiliated calibrators were 2.7％ -5.9％ and 2.7％ -7.5％,respectively.The results of LoB,LoD and FS were 2.5,7.8 and 8.8 pg/ml,respectively.AMR was 8 -35 126 pg/ml,and the most suitable dilution rate was 1∶ 2,so the CRR was 9 -70 252 pg/ml.428 μmol/L bilirubin,2 g/L haematoglobin and 2 200 FIU chyle didn't interfere with the NT-proBNP assay.Moreover,almost all the data from different age groups were in the range of biological reference intervals declared by the manusfacturers, except one test data (167 pg/ml).Conclusions The analyticalperformance of NT-proBNP analyzed on Roche Cobas E601electrochemiluminescence immunoassay systemisconsistentwiththestandarlswhichmanufacturershas proclaimed.The establishment of LoD,FS,maximal dilution and CRR for NT-proBNP assay could provide the quality assurance for clinical use and the biological reference intervals declared by manusfacturers could meet the clinical needs.