Objective To evaluate the performance of the Beckman Coulter ACT-5DIFF AL automated hematology analyzer and to verify whether it meets the clinical requirement.Methods The residual contamination rate,accuracy,precision,uncertainty,measurement range,reference interval,and sample injection pattern of detecting system were evaluated.Results The residual contamination of each parameter was less than or equal to 0.18％.According to room between qualitative evaluation results,compared to the target value,bias ranged from 0.32％ to 2.29％.Different concentrations of laboratory variation coefficient (namely precision) of each parameter ranged from 0.35％ to 4.46％,and both of which were less than a third of the CLIA'88 ability verification analysis quality requirements.The expanded uncertainty of each parameter was Uwhite blood cell (WBC) low =7.4％,UWBC high =3.8％,Ured blood cell (RBC) low =3.4 ％,U RBC high =2.8 ％,Uhemoglobin (HGB) low =3.9 ％,UHGB high =2.2 ％,Uplatelet (PLT) low =9.8 ％,UPLT high =7.6％,UMCV low =2.6％,and UMCV high =2.5％.Analysis had a wide measuring range:WBC (0.2 ～ 137.3) × 109/L,RBC(0.72 ～ 7.66) × 1012/L,HGB (20 ～ 231)g/L,PLT(25 ～983) × 109/L,and hematocrit (HCT) (6.1 ～68.0)％.All of them had a linear relationship,and the correlation coefficient of linear regression was close to 1.0.The reference interval quoted was suitable.Both of the automatic and the hand sample injection pattern had no significantly difference in result detection.Five categories of WBC were verified up to standard.Conclusions Under the circumstance of indoor quality control approved,each performance indicator approximately reached the laboratory quality requirements,and it also met the clinical requirements.

Objective To investigate the distribution and drug resistance of major pathogens for urinary tract infections in the First Affiliated Hospital of Nanjing Medical University.Methods Strains from midstream urine culture of patients with urinary tract infections were collected during January 1 and December 31,2011.All strains were identified by API system,and disk diffusion method was used for drug sensitivity test.Results Totally 1129 strains were isolated,in which 667 (59.1％ ) were Gram-negative strains,266 (23.5％) were Gram-positive strains,and 196 (17.4) were Candida.Among Gram-negative strains,Escherichia coli,Klebsiella pneumoniae and Proteus mirabilis were highly sensitive to carbapenem antibiotics; while Acinetobacter baumannii and Pseudomonas aeruginosa were highly resistant to most antibiotics including cephalosporins and penicillinase inhibitor,and the resistance rates were over 50％.Among Gram-positive strains,the major strains Enterococcus avium and Enterococcusfaecalis were completely sensitive to vancomycin and teicoplanin,and highly sensitive to linezolid (resistance rate below 10％ ).Candida albicans and Candida glabrata were highly resistant to voriconazole and fluconazole (with the resistance rates of 47.2％ - 60.0％ ), but were completely sensitive to amphotericin and nystatin.Conclusion Gram-negative strains account for most urinary tract infections in the First Affiliated Hospital of Nanjing Medical University with high drug resistance rates.

BACKGROUND:Induction of osteoblasts differentiating into osteocytes is a hot spot in tissue engineering;however, the regulatory mechanism underlying differentiation has not been ful y elucidated. MicroRNA, as an endogenous smal RNA molecule, can regulate post-transcriptional gene expression by binding to the 3’ nontranslated region of the target gene mRNA, which also has been found to play an important regulatory role in osteocyte differentiation. OBJECTIVE:To study the regulation of miR-155 on osteoblast differentiation and the underlying mechanism. METHODS:The mouse osteoblast cel lines MC3T3-E1 were selected and induced by mouse bone morphogenetic protein-2 (BMP2, 200 ng/mL) and then the miR-155 mRNA expression was determined by quantitative real-time PCR at 1, 3, 7 and 14 days. MC3T3-E1 cel s were divided into control, BMP2, miR-155 and miR-155 inhibitor groups, fol owed by cultured withα-MEM medium, BMP2, miR-155 and miR-155 inhibitor, respectively, for 2 weeks. RESULTS AND CONCLUSION:After induction using BMP2, miR-155 expression was downregulated in a time dependent manner. The staining intensity of alizarin red in the BMP2 group was significantly higher than that of the control group, and the activity of alkaline phosphatase and mRNA expression were also significantly higher than those in the control group (P<0.01). The staining intensity of alizarin red, activity of alkaline phosphatase and mRNA expression in the miR-155 group were significantly lower than those in the control group (P<0.01), while al above measurements were reversed significantly by miR-155 inhibitor (P<0.05). miR-155 could bind to the 3’ untranslated region of SMAD5 mRNA and significantly downregulated the expressions of SMAD5 protein and mRNA in MC3T3-E1 cel s (P<0.01). These results show that miR-155 can inhibit MC3T3-E1osteogenic differentiation by downregulating SMAD5 expression.

Objective To investigate the serum levels of high sensitivity C-reactive protein (hsCRP),interleukin-1β (IL-1β) and lipoprotein-associated phospholipase A2 (Lp-PLA2),and investigate their clinical diagnostic value in acute coronary syndrome (ACS) patients.Methods Fifty three clinical serum samples of patients specifically diagnosed with acute coronary syndrome were collected.A total of 21 healthy subjects were enrolled as healthy controls.Serum IL-1β and Lp-PLA2 levels were determined by enzyme-linked immunosorbent assay.The concentration of hs-CRP was tested by immunoturbidimetry method.Results Compared to the healthy controls,the levels of serum hs-CRP,IL-1βand Lp-PLA2 were significantly higher in ACS and ACS subgroups (P ＜ 0.05),respectively.The level of Lp-PLA2 was gradually increased among healthy controls,angina pectoris (AP),ST-segment elevation myocardial infarction (STE-MI),non-ST-segment elevation myocardial infarction (NSTEMI) groups.The best cut-off value of hs-CRP,IL-1β and Lp-PLA2 was 7.44 mg/L,90.88 ng/L and 219.92 μg/L,respectively.The parallel test had better sensitivity (94.3％) and specificity (100％).Conclusions Serum hs-CRP,IL-1β and Lp-PLA2 play an important role in classifying the clinical types and monitoring the conditions of patients with ACS.Combination of hs-CRP,IL-1β and Lp-PLA2 is expected to be a new biomarker for ACS.

Objective To investigate the changes and clinical significance of serum lactate dehydrogenase (LDH),creatine kinase (CK),glutamate pyruvate transaminase (AST),and cerebrospinal fluid lactate dehydrogenase (CSF LDH) in adult patients with acute central nervous system infection.Methods The levels of myocardial enzymes (AST,LDH,and CK) in serum of 96 adult patients with acute intracranial infection in 7days and 39 healthy people were measured by Beckman automatic biochemical analyzer and enzyme rate assay,and CSF LDH level in 96 patients were measured simultaneously.Results (1) The serum myocardial enzymes (LDH,CK,and AST) of intracranial infection group (47 cases with viral encephalitis,30 cases with tuberculous meningitis,and 19 cases with purulent encephalitis) were significantly higher than those of normal control group (P ＜0.01).(2)The myocardial enzymes (LDH,and AST ) of patients with cerebral functional disorder were significantly higher than those of patients with normal cerebral function (P ＜0.05).(3)The levels of serum AST,LDH,and CK in the virus encephalitis group,serum AST and LDH in the purulent encephalitis group,and serum LDH in the tuberculous meningitis group were significantly higher than those in the control group (P ＜ 0.01).The CSF LDH level in the viral meningitis group was prominently lower than that in the tuberculous encephalitis group and purulent encephalitis group,respectively (P ＜0.01).(4) No correlations were found between CSF LDH and serum myocardial enzymes (P ＞0.05).Conclusions (1)There is significant change in the levels of serum LDH,CK,AST,and CSF LDH of adult patients with acute intracranial infection,especially in infected patients with cerebral functional disorder,and the change of LDH is the most obvious.(2)The levels of serum myocardial enzymes and CSF LDH are helpful to the differential diagnosis of intracranial infection in early stage,and judging the severity of the illness.

Objective To detect the expression level of aquaporin 8 (AQP8) in patients with functional constipation(FC) or constipated irritable bowel syndrome (IBS-C),and the correlation between the expression of AQP8 and clinical features.Methods From March to December 2014,a total of 16 patients with IBS-C and 19 patients with FC met Rome Ⅲ criteria were collected,and nine healthy individuals were assigned to control group at the same period.The ascending and decending colonic tissues mucosa of FC,IBS-C and control group were taken under endoscope.The expression of AQP8 at mRNA and protein level was detected by real-time polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC).The differences in AQP8 mRNA expression and AQP8 relative area were analyzed by Kruskal-Wallis test among groups,and Pearson correlation coefficient was performed for correlation analysis between the expression and clinical features.Results The relative expressions of AQP8 mRNA of ascending colon and descending colon of FC patients (1.38,0.61 to 4.09;2.65,0.82 to 7.52) and IBS-C patients (2.23,0.82 to 4.67;1.35,0.51 to 2.03) were higher than those of control group (0.56,0.19 to 0.97;0.38,0.21 to 1.19),and the differences were statistically significant (ZFc =-2.435,-3.149,ZIBS-C =-2.690,-2.152;all P＜0.05).AQP8 mRNA expression of descending colon in patients with FC was higher than that of patients with IBS-C,and the difference was statistically significant (Z =-2.003,P =0.045).The expression of AQP8 in patients with FC and IBS-C was positively correlated with disease course (ascending colon r=0.57 and 0.53;descending colon r=0.49 and 0.54,all P＜0.05),and was negatively correlated with frequency of defecation (ascending colon r=-0.82 and-0.61;descending colon r=-0.49 and-0.53,all P＜0.05).There was no correlation between the expression of AQP8 and age,gender,onset age,presence of abdominal symptoms of the patients (all P＞ 0.05).Most of AQP8 of FC group was expressed in cytoplasm of colonic mucosa epithelial cells,while that of IBS-C group and control group was mostly expressed at apical membrane and basal membrane of epithelial cells.The results of semi-quantification demonstrated that AQP8 relative area of descending colon of FC and IBS-C group increased compared with that of control group (3.42％ (1.24％ to 5.61％),2.45％(1.72％ to 4.27％) vs 1.18％ (0.35％ to 2.81％);Z=-2.534,-2.151,both P＜0.05).Meanwhile,AQP8 relative area of ascending colon of FC group increased compared with that of control group (2.46％(1.48％ to 4.18％) vs 1.14％(1.29％ to 2.15％) Z=-2.041,P＜0.05).Conclusion There are differences in AQP8 expression quantity and location in cells of descending colon between patients with FC and patients with IBS-C,which is a way for differentiation these two diseases.

Objective To investigate the diagnostic value of enzyme-linked immunospot assay for tuberculosis (T-SPOT.TB) in pulmonary tuberculosis and non-pulmonary tuberculosis,and evaluate the clinical application value of T-SPOT.TB's spot forming cell frequencies in the diagnosis of tuberculosis.Methods T-SPOT.TB,tuberculin test (PPD) assay,and tuberculosis antibody test (TB.AB) were used in the diagnosis of tuberculosis among 78 active pulmonary tuberculosis patients,58 active non-pulmonary tuberculosis patients,27 old pulmonary tuberculosis patients,and 76 non-tuberculosis patients.Results (1) The sensibility and specificity if T-SPOT.TB assay were 71.17％ and 78.95％,the highest among 3 methods.Three trials's joint detection obviously increased the sensitivity of tuberculosis diagnosis.(2) The positive rate of T-SPOT.TB and spot forming cell frequencies in active pulmonary tuberculosis and active non-pulmonary tuberculosis were not statistically significant (P ＞ 0.05).The positive rate of T-SPOT.TB in active pulmonary tuberculosis and old pulmonary tuberculosis were not statistically significant (P ＞ 0.05).However,spot forming cell frequencies of T-SPOT.TB in active pulmonary tuberculosis were significantly higher than old pulmonary tuberculosis (P ＜ 0.05).(3) When spot forming cell frequencies of T-SPOT.TB.of peripheral blood mononuclear cell (PBMC) was set to 11.5 spots-forming cell (SFC)/106 PBMC,it had the best cut-off value to diagnose the tuberculosis as a diagnostic criteria.(4) When spot forming cell frequencies of T-SPOT.TB of PBMC was set to 17 SFC/106pBMC,it had the best cut-off value to distinguish the active pulmonary tuberculosis from old pulmonary tuberculosis.Conclusions The joint detection of TSPOT.TB assay,PPD assay and TB.AB assay,could obviously improve the positive rate of TB infection.TSPOT.TB assay has useful diagnostic value for pulmonary tuberculosis and non-pulmonary uberculosis.Reasonable application of spot forming cell frequencies contributes to the early diagnosis and treatment of tuberculosis.