Establishment of electrical immunosensor for the detection of nuclear matrix protein-22 / 中华检验医学杂志

Objective@#A label-free electrochemical immunosensor was developed for the detection of nuclear matrix protein-22 (NMP22) as a biomarker of bladder cancer.@*Methods@#The study was based on the establishment and validation of the methodology. Urine samples were collected from 20 patients with bladder cancer and 20 controls in the affiliated Hongqi hospital of Mudanjiang medical university from September in 2017 to July in 2019 to validate the developed method. A screen-printed electrode (SPE) was modified with a film of a composite made from the reduced graphene oxide-tetraethylene pentamine (rGO-TEPA) immobilized Zn-based-Metal-organic frameworks deposited with Au nanoparticles (rGO-TEPA@Au-ZIF8). Primary antibody against NMP22 was immobilized on the Au nanoparticles on the surface of the modified SPE, which then was blocked with bovine serum albumin to elimiate nonspecific binding sites. The process of the construction of the proposed sensorwas characterized by cyclic voltammetry and electrochemical impedance spectroscopy. Differential pulse voltammetry was used to evaluate the linear range, recovery, precision, selectivity and stability. The data were analyzed by Mann-Whitney U test.@*Results@#Under optimal conditions, the immunosensor exhibited a linear range of 0.01-1000 ng/mlwith a detection limit of 3.33 pg/ml (S/N=3) and a standard recovery of 97.65%-107.05%. The levels of NMP22 in urine samples from patients with bladder cancer [66.03 (4.34, 91.74)]ng/ml determined by the proposed sensor were significantly higher than those of controls 0.54(0.06, 8.84) ng/ml(P=0.001).@*Conclusion@#The immunosensor can achieve sensitive, rapid and acucurate detection of NMP22, and has potential application prospects in monitoring tumor markers.

Establishment of electrical immunosensor for the detection of nuclear matrix protein-22 / 中华检验医学杂志

Objective A label-free electrochemical immunosensor was developed for the detection of nuclear matrix protein-22 (NMP22) as a biomarker of bladder cancer. Methods The study was based on the establishment and validation of the methodology. Urine samples were collected from 20 patients with bladder cancer and 20 controls in the affiliated Hongqi hospital of Mudanjiang medical university from September in 2017 to July in 2019 to validate the developed method. A screen-printed electrode (SPE) was modified with a film of a composite made from the reduced graphene oxide-tetraethylene pentamine (rGO-TEPA) immobilized Zn-based-Metal-organic frameworks deposited with Au nanoparticles (rGO-TEPA@Au-ZIF8). Primary antibody against NMP22 was immobilized on the Au nanoparticles on the surface of the modified SPE, which then was blocked with bovine serum albumin to elimiate nonspecific binding sites. The process of the construction of the proposed sensorwas characterized by cyclic voltammetry and electrochemical impedance spectroscopy. Differential pulse voltammetry was used to evaluate the linear range, recovery, precision, selectivity and stability. The data were analyzed by Mann-Whitney U test. Results Under optimal conditions, the immunosensor exhibited a linear range of 0.01-1000 ng/mlwith a detection limit of 3.33 pg/ml (S/N=3) and a standard recovery of 97.65％-107.05％. The levels of NMP22 in urine samples from patients with bladder cancer [66.03 (4.34, 91.74)]ng/ml determined by the proposed sensor were significantly higher than those of controls 0.54(0.06, 8.84) ng/ml(P=0.001). Conclusion The immunosensor can achieve sensitive, rapid and acucurate detection of NMP22, and has potential application prospects in monitoring tumor markers.

Effects of chronic benzene poisoning on DNA and antioxidase of mice / 中国组织工程研究

BACKGROUND:As an important industrial solvent,benzene can cause DNA damage,chromosome aberrence,formation of DNA adducts and gene mutation. OBJECTIVE:To explore the effects of benzene on DNA and the mechanism,as well as the changes of antioxidase system it caused. DESIGN:Randomized case control study. SETTING:The Department of Clinical Laboratory of First Affiliated Hospital and Public Health College of Harbin Medical University. PARTICIPANTS:The experiment was completed in the Animal Centre in Public Health College,Harbin Medical University.Twenty-four healthy male mice of Kunming species weighed between 18 g to 22 g were chosen.The mice were provided by Experimental Animal Centre of Second Affiliated Hospital,Harbin Medical University. INTERVENTIONS:The mice were divided into control group,low dose benzene group and high dose benzene group.Inhaling benzene smoke method was used 4 hours per day to cause benzene poisoning to mice except those of the control group.The mice were executed two months later to separate marrow cells and peripheral lymphocytes and remove liver,spleen and brain to make homogenate. MAIN OUTCOME MEASURES:Single cell gel electrophoresis (SCGE) was used to assay the DNA damages of marrow cells and peripheral lymphocytes.Meanwhile,the contents of superoxide dismulase(SOD),glutathione peroxidase(GSH-Px) and malondialdehyde(MDA) in liver,spleen and brain tissues were also detected. RESULTS:The comet percentage of marrow cells and peripheral lymphocytes in two benzene poisoning groups were(83.56± 10.28),(92.54± 15.93)% ,and(41.27± 6.03)% ,(65.79± 11.62)% respectively which were much higher than those in control group[(4.13± 0.52)% ,(2.21± 0.31)% ](P< 0.01) and represented dose-response relationship.The SOD activity of liver homogenate and GSH-Px activity of high dose and low dose groups were (11 573.31± 1 938.72),(12 574.68± 1 938.72) nkat/g and (309.40± 82.85),(375.41± 55.18) nkat/g respectively which were much lower than those in control group [(16 668.67± 3 137.96),(588.62± 110.52) nkat/g] (P< 0.05).However, there was no significant difference between different dose groups. The GSH-Px activity in spleen homogenate in two experimental groups was(421.75± 124.02) and(523.10± 45.18) nkat/g respectively which was much lower than that of control group [(618.42± 57.01) nkat/g](P< 0.05) and there was significant difference between two groups (P< 0.05).In the brain homogenate of both benzene groups,the GSH-Px activity was(87.35± 19.84) and(95.02± 14.00) nkat/g respectively which was much lower than that of control group[(118.36± 7.67) nkat/g] (P< 0.05) and without difference between two groups.The MDA content in brain homogenate of high dose group was(3.99± 1.15) μ mol/mg which was much higher than that of control group [(2.58± 0.53) μ mol/g] (P< 0.05). CONCLUSION:Chronic benzene poisoning can cause DNA impairment of marrow cells and peripheral lymphocytes and reduce the activity of antioxidase.

Antioxidant status and products of oxidative stress in colorectal cancer / 医学研究生学报

Objective:Colorectal cancer is related to antioxidative ability and oxidative stress level.The aim of the study was to evaluate the oxidative stress in colorectal cancer patients and to investigate the relationship between oxidative stress and colorectal cancer.Methods:A total of 60 subjects(30 colorectal cancer patients,30 normal healthy controls) were examined in the study and estimated the protein oxidation,DNA damage,lipid peroxidation and antioxidants-vitamin C,vitamin E,glutathione(GSH) and antioxidative enzymes in serum,respectively.Results:Statistically significantly higher values of protein carbonyl and advanced oxidation protein products(AOPP) were observed in colorectal cancer patients(P