1.Exploration of the verification process for the analytic performance of the quantitative project of molecular diagnosis
Huili LUO ; Hang YUAN ; Yuan MAO ; Houzhi ZHANG
International Journal of Laboratory Medicine 2015;(16):2360-2362
Objective To explore the verification process for the analytic performance of the quantitative project of molecular di-agnosis.Methods Based onMedical laboratory accreditation criteria for quality and competence in the field of molecular diagnos-tics application note(CL-36)(2014)and the relevant documents published by Clinical and Laboratory Standards Institute (CLSI), the performance verification methodology of PCR detection for hepatitis b virus nucleic acid was achieved.for.Results The within-run precision of DNA detection for the hepatitis b virus was 0.109 and 0.105;and the between-run precisionwas 0.1 57 and 0.137. Compared with the reference laboratory,the regression equation was Y =0.947+0.343X ,and the linear correlation coefficient was 0.990.The linear range was 5.00-1.10 and thequantitative detection limit was 500 IU/mL.Hemolysis had no effect on the detec-tion of samples.Conclusion The laboratory with molecular diagnostic program should conduct analytic performance verification,and the appropriate method should be chosen to clear performance verification.Conclusion Clearing the performance indicators of de-tection projects has a very positive role in the clinical use of detection projects..
2.The gene expressions of matrix metalloproteinase-1 and its inhibitor in peripheral blood mononuclear cells from patients with chronic hepatitis B
Jianzhen ZHANG ; Junqing YI ; Houzhi CHEN ; Bin HU ; Chunlan ZHANG ; Zhan YANG
Chinese Journal of Infectious Diseases 2009;27(12):738-741
Objective To examine the gene expression levels of matrix metalloproteinase-1(MMP-1), tissue inhibitor of metalloproteinase-1 ( TIMP-1) in peripheral blood mononuclear cells (PBMC) and sera in the patients with chronic hepatitis B (CHB) and to investigate the value of message RNA(mRNA) expression of MMP-1 and TIMP-1 for diagnosing liver fibrosis. Methods PBMC and sera samples were collected from 37 CHB patients and 20 healthy controls. The total RNA isolated from PBMC was reversely transcribed into cDNA. The mRNA levels of MMP-1 and TIMP-1 in PBMC were examined by real-time fluorescence quantitative reverse transcription polymerase chain reaction (FQ-RT-PCR). The serum levels of MMP-1 and TIMP-1 were determined by sandwich enzyme-linked immunosorbent assay (ELISA). Liver tissues were obtained from all these patients by biopsy and subsequently used for evaluating liver fibrosis stages (S). Intergroup comparison was performed by non parametric test. The correlation analysis was performed by Spearman. Results The MMP-1 and TIMP-1 mRNA levels in PBMC from healthy controls were low. The MMP-1 mRNA levels in PBMC from CHB patients were not significantly different from those in healthy controls,while the TIMP-1 mRNA levels were remarkably higher in CHB patients' PBMC compared to healthy controls. Both the MMP-1 mRNA levels in PBMC and the MMP-1 protein levels in sera were not significantly different among CHB patients at different disease stages and healthy controls (χ~2 =8. 960,P=0.111l ;χ~2 =7. 898, P = 0.211). However, the TIMP-1 mRNA levels in PBMC and the TIMP-1 protein levels in sera increased gradually along with the disease progressed from S1 to S4. The TIMP-1 mRNA levels in PBMC were (1.67±0. 84) lg copy/μL, (3. 48±2. 08) lg copy/μL,(5. 86±3. 47) lgcopy/μL and (8. 14 ± 6. 48) lg copy/μL from stage 1 to 4 respectively, while the protein levels of TIMP-1 in sera were (233. 73±64. 84) ,μg/L, (262. 10±71. 12) μg/L, (301. 15±62. 74)μg/L and(381. 15 ± 152. 75)μg/L, respectively. The differences between each stages were statistically significant (χ~2'= 14. 290, P=0.002,χ~2 = 12.209, P=0. 007). The TIMP-1 mRNA levels in PBMC and the TIMP-1 serum levels were positively correlated with liver fibrosis stage (r=0. 752, P<0. 01;r=0. 530, P=0. 008). Conclusions The TIMP-1 mRNA level in PBMC and TIMP-1 protein level in serum are closely related with liver fibrosis stages. These two parameters, especially the TIMP-1 mRNA level in PBMC, can be potentially new markers for diagnosing liver fibrosis.
3.Molecular mechanism of the changes in ventricular electrical remodeling caused by mechano-electrical feedback in rabbits with congestive heart failure.
Juelin DENG ; Mao CHEN ; Qing YANG ; Houzhi YU ; Tao ZHANG ; Qian YU ; Dejia HUANG
Journal of Biomedical Engineering 2009;26(1):50-54
This study sought to explore the relationship between the change in ventricular electrical remodeling caused by mechano-electrical feedback and the expression of L-type Ca2+ -channel and/or sarcoplasmic reticulum Ca2+ -ATPase in the rabbits with congestive heart failure (CHF). 138 rabbits were divided into two groups (CHF and control). We measured the ventricular monophasic action potential duration (MAPD) and ventricular effective refractory period (VERP) during ventricular pacing at the stimulus frequency of 220/240/260 bpm in these rabbits. Rapid atrial pacing (260/min) was given for 30 minutes. The MAPD and VERP were measured again. Then ventricular fibrillation was induced by S1S2S3 program stimulation. We extracted the total RNA from the myocardium respectively and detected L-type Ca2+ -channel mRNA and sarcoplasmic reticulum Ca2+ -ATPase mRNA by use of Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). In group CHF, with the increasing of preload/afterload, L-type Ca2+ -channel mRNA was up regulated after rapid atrial pacing when compared with that in control groups (P < 0.05). There was no significant change in sarcoplasmic reticulum Ca2+ -ATPase mRNA after rapid atrial pacing when compared with controls (P > or = 0.05). The changes in MAPD90 and VERP were related with the extent of L-type Ca2+ -channel mRNA up regulation. But the changes in MAPD90 and VERP were not significantly related with the extent of sarcoplasmic reticulum Ca2+ -ATPase mRNA up regulation. These findings suggest that Mechano-Electrical Feedback could increase the regional changes of ventricular electrical remodeling in rabbits with CHF and so to predispose them to ventricular arrhythmia. The changes may be related with the up regulation of L-type Ca2+ -channel mRNA, but not with sarcoplasmic reticulum Ca2+ -ATPase mRNA.
Action Potentials
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Animals
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Calcium Channels, L-Type
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genetics
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metabolism
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Cardiac Pacing, Artificial
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Electric Conductivity
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Electrophysiology
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Female
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Heart Failure
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metabolism
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physiopathology
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Male
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RNA, Messenger
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genetics
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metabolism
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Rabbits
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Random Allocation
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Refractory Period, Electrophysiological
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Sarcoplasmic Reticulum
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genetics
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metabolism
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Ventricular Remodeling