Objective To investigate the stability of glycated hemoglobin HbA1c in whole blood sample measured by Tosoh G7, Roche/Hitachi 7170A and NycoCard READER Ⅱ under different storage conditions. Methods Three whole blood samples (EDTA anticoagulated) with different glycated hemoglobin levels and one whole blood sample (heparin anticoagulated) were collected and stored at -80 ℃, -20 ℃, 4 ℃,room temperature(15 -25 ℃), and 37 ℃ HbA1c was analyzed by each method on days 1, 2, 5, 7, 9, 14, 21,28, 35, 42, 49, 56, 63 and 70 respectively. Results The results of sample stored at -80 ℃ appear to be stable for Tesoh G7 and Roche/Hitachi 7170A method. The coefficients of variation (CV) for Tosoh G7 was 0.54%-1.22%. The CV for Roche/Hitachi 7170A was 0.86% -1.82%. When samples was detected with Tosoh G7 method, the results was consistent when the sample was stored at -20 ℃ for 14 days, 4 ℃ for 63 days, room temperature for 5 days, and 37 ℃ for less than 1 day. When samples was detected with Roche/Hitachi 7170A method, the results was consistent when the samples was stored at -20 ℃ for 21 days, 4 ℃ for 42 days, room temperature for 7 days, and 37 ℃ for less than 1 day. The NycoCard READER Ⅱ showed stability at 4 ℃ for 9 days, and room temperature for less than 1 days. Conclusions The stability of whole blood samples is dependent on different methods. Storage time under different temperatures is different.

Objeetive To explore change of platelet glycoproteins Ⅵ(GPⅥ)in patients with type 2 diabetes mellitus and its clinical significance.Methods The surface expression of platelet glycoprotein Ⅵ was determined by flow cytometry in 56 patients with type 2 diabetes mellitus and 61 normal individuals.Plasma GP Ⅵ concentration was measured by ELISA in 30 patients with type 2 diabetes mellitus.Platelet surface CD62P was analyzed by flow cytometry and HbA1c was determined in Datients with type 2 diabetes mellitus.Results The geometric mean fluorescence of platelet surface GPⅥ in Datients with type 2 diabetes mellitus was 93.66±35.24,which was significantly enhanced compared with normal subjects (62.83±24.2)(t=-4.927,P＜0.05).Nine patients were positive in plasma GPⅥ among 30 Datients with type 2 diabetes mellitus.Plasma GP Ⅵ concentrations in 9 positive patients were conversely correlated with platelet surface GPⅥ expression(r=-0.633,P＜0.05).However,there was no correlation between platelet Surface CD62P and plasma HbA1c concentrations, and the correlation coemcient is -0.333 and -0.417,respectively(P＞0.05).There was no correlation between platelet surface GP Ⅵ expression with C062P and HbA1c in patients with type 2 diabetes mellitus and the conrrelation coefficient is -0.009 and -0.217,respectively(P＞0.05).Conclusions GPⅥ expression on platelet surface is elevated in Datients with type 2 diabetes mellitus and the determination of platelet surface GPⅥ and plasma GPⅥ concennlation may helP to prognosticate the risk of thrombotic events and may play an important role in evaluating platelet activation in patients with type 2 diabetes mellitus.

Objective To research on a whole blood control material for lymphocyte subset counting by flow cytometry(FCM).Methods To detect lymphocyte subset in whole blood with different preservers by flow cytometric multi-color analysis.Results whole blood control material for lymphocyte subset counting by FCM was prepared.In 2-8℃ refrigerator, the light scatter and CD45 of leukocytes of whole blood control were stable in 72 days. The cluster of lymphocyte, monocyte, neutrophil in plot were separated easily from debris. The lymphocyte subset of whole blood control can be counted by FSC/SSC or CD45/SSC gating. The variation of lymphocyte subset count was less in different preserving day. The coefficient of variation (CV) of lymphocyte subset count was less than 6.5% in our laboratory and less than 13% in external quality assessment among 56 laboratories in China.Conclusion The whole blood control prepared by us can be used for internal quality control and external quality assessment in lymphocyte subset counting by FCM, it is very important signification to ensure the quality and accuracy of lymphocyte subset count.

Objective To investigate the results of different measuring procedures of hemoglobin A1c (HbA1c) trueness verification scheme in China.Methods Cross sectional survey.The data were collected via the External Quality Assessment (EQA) software from laboratories participated in the First HbA1c trueness verification EQA.Then the collected data were divided into several groups based on laboratory instruments and the data from less than 5 group were excluded.The observed imprecision, bias and sigma (σ) were calculated and the bias％ and CV％ were drew in the sigma chart.The average bias％, CV％ and weighted average σ of each level were also calculated.Results Total 123 laboratories were divided into 9 groups and setting 6％ as the Allowable Total Error, the average bias％, CV％ and weighted average σ of 201411 (target value was 5.4％) were 3.70％, 4.55％ and 0.51 respectively σ, of 201412 (target value was 7.8％)were 2.42％ , 3.56％ and 1.24σ respectively.None of the group achieved the 2σ quality of 201411, and 1 group achieved the 2σ quality of 201412.Conclusions There are obvious biases among the results of many measuring systems and the target value assigned by reference measuring procedures of HbA1c, as well as the imprecision.The Sigma External Quality Assessment Chart is a visual tool, indicating that the quality of measuring systems necessitate improvement therefore to ensure the reliability of results and make better use of HbA1c in clinical application.

This article summarized recent correlative literatures focusing on international standards on glycated hemoglobin.The basic concept,determination of glycated hemoglobin,the present review in laboratory measurement and metrological traceability was introduced.The international community has established reference system and metrological traceability to the International System of Units on HbA1c.Determination in glycated hemoglobin is still in incipient stage in our country.Both clinical laboratorians awareness and clinical determination need to be strengthened.

Objective To express and purify recombinant human platelet glycoprotein Ⅵ extracellular domain and prepare the polyclonal antibody against it.Methods Human platelet glycoprotein Ⅵ extracellular domain fragment (123~268 residues) was amplified by polymerase chain reaction and cloned into the prokaryotic expression vector pGEX-3x.The recombinant plasmid was constructed and expressed in E.coli after induction with isopropyl-?-D-thiogalactopyranoside (IPTG).The fusion protein was identified by Western blot analysis after purification by affinity chromatography.Rabbits were immunized with the purified fusion protein, and the collected rabbit antiserum was evaluated by sandwich ELISA, Western blot and flow cytometry.Results The coding sequence of GPVI extracellular domain was successfully inserted into pGEX-3x.Sequencing result showed that the cloned gene was identical as reported.After induction, a Mr 42kd fusion protein was expressed and confirmed by Western blot, which was identical to that expected.The titers of the antisera were up to 1∶[KG-*2]128. Sandwich ELISA result demonstrated that the prepared antibody recognized GPVI in human platelet. Western blot and flow cytometry revealed that the prepared antibody reacted with GPVI of platelet lysate and the native GPVI on human platelet surface.Conclusions Using purified prokaryotic expressed the fusion protein as antigen, the specific antibody was elicited in the immunized animals. The prepared polyclonal antibodies react specially with GPVI on human platelet surface and can be used for further studies of GPVI.

Objective To investigate the current situation of precision of internal quality control (IQC) in total cholesterol,triglyceride,HDL-cholesterol,and LDL-cholesterol and provide improvement measurements.Methods Web-based External Quality Assessment (EQA) system was used to collect IQCdata of lipid tests from 581 EQA participant laboratories nationwide.The data include the coefficient of variation (CVs) of IQC data under control in April 201 1 and long-term cumulative data.Excel 2007 was applied for data processing after excluding the invalid data.Acceptable rates of CVs of two-lot internal quality controls in 4 lipid testing were calculated according to 6 criteria,that were 1/4TEa,1/3TEa,allowable imprecision of National Cholesterol Education Program (NCEP) and the specifications based on biological variation including the optimal,appropriate and minimal allowable imprecision.Results Four hundred and thirty-five,434,405 and 360 laboratories reported the data of level 1 IQC for total cholesterol (TC),triglyceride (TG),HDL-C,LDL-C respectively,while 214,214,192 and 171 reported the data of level 2 IQC respectively.Acceptable rates of TC,TG,HDL-C,LDL-C based on NECP criteria were 69.2％ (304/435),85.3％ (370/434),61.3％ (48/405) and 69.0％ (248/360) for level 1 respectively while 81.3％(174/214),91.6％ (196/214),75.5％ (145/192) and 81.3％ (139/171) for level 2 respectively.In the group which met the NECP criteria,the proportion of using matching detection system was much higher than the group which did not meet the criteria.Conclusions It is an effective way for clinical laboratories to improve test quality by monitoring the current and cumulative CVs of internal quality control and comparing them against proper evaluation criteria to evaluate if the analysis system can meet quality requirements.

Objective To study the applicability of a new analytical specification defined in WS/T 403-2012 in the external quality assessment schemes and the external comparision of internal quality control .Methods It was a quality management method study.Total error allowable criterions listed in WS/T 403-2012 and GB/T 20470-2006 were selected to assess the results of 23 analytes in the 1st challenge of 2013 routine chemistry external quality assessment.The acceptable rate of 23 analytes were calculated with the two specifications.Criterions of imprecision derived from the two standards were applied to assess the coefficient of variation with internal quality control data.Results With the specification based on WS/T 403-2012, the ratio of laboratories that all five samples were passed in the 1st challenge for 23 analytes ranged from 55.5%to 94.7%.The ratio of laboratories with 80%or more samples passed in 2013 EQA ranged from 73.9%to 98.5%.While ratios of two kinds described above evaluated based on GB /T 20470-2006 ranged from 63.0%to 99.2%, and from 90.0% to 99.7%, respectively.The acceptable rate of CV according to the two criterions ranged from 55.5% to 94.7% and 63.0% to 99.2%, respectively.Conclusions As evaluation criterions of external quality assessment allowable total error and internal quality control imprecision in routine chemistry , the specification in WS/T 403-2012 can be used to assess the analytical performance of clinical laboratory more objectively and comprehensively.It can help laboratories to identify the latent problems for further quality improvement.

Objective To explore the effect of kidney transplantation from donation after brain death (DBD) donors with terminal acute renal failure (ARF).Method The clinical data of kidney transplantation from DBD donors with ARF were retrospectively analyzed,and only standard criteria donors (SCD) were included.The results of kidney transplants from ARF donors were compared with those of kidney transplants from DBD donors with normal renal function (serum creatinine ＜ 133μmol/L) performed from January 2012 to March 2014.Result There were 13 donors with ARF and 27 donors with normal renal function (non-ARF donors).The ARF donors had significantly higher terminal serum creatinine than the non-ARF donors (394.9 ± 176.8 vs.75.4 ± 28.6 μmol/L,P＜0.001),but the initial serum creatinine (79.1 ± 17.2 vs.71.0 ± 22.8 μmol/L) and the best creatinine clearance rate (128.3 ± 33.0 vs.129.8 ± 46.8 ml/min) of two groups showed no significant difference (P＞0.05).Twenty-six recipients received kidney transplants from ARF donors (ARF group) and 54recipients received kidney trangplants from donors with normal renal function (non-ARF group).There was no significant difference in the incidence of delayed graft function and acute rejection between ARF and non-ARF kidneys (0 vs.1.9％,and 11.5％ vs.7.4％,respectively).The ARF group had significantly lower estimated glomerular filtration rate (eGFR) at 1st month after transplantation (54.3 ± 16.9 vs.62.5 ± 14.2 mL·min 11.73 m 2,p =0.025),but the eGFRs of two groups were similar at 6th and 12th month after transplantation.During a mean follow-up period of 11.5 months (range 3 to 28 months),actual patient and graft survival rate for both groups were 100％.Conclusion Kidneys from DBD donors with terminal ARF have excellent short-term outcomes and may represent another potential method to safely expand the donor pool.

External quality assessments play important roles in quality improvement in clinical laboratories, but most laboratories focused on the unsatisfied data only.With appropriate quality controls, laboratories can detect not only the error sourses of unsatisfied data but the potential error sourse of satisfied data as well.