1.The effects of Streptococcus sobrinus on corrosion behavior of metal-ceramic alloys
Lei CHEN ; Hui CAI ; Changyun FANG
Journal of Practical Stomatology 1996;0(02):-
Objective:To study the corrosion resistance of four metal-ceramic alloys in the presence of Streptococcus sobrinus, and to compare the effects of bacteria action in liquid and solid environment.Methods:Four metal-ceramic alloys were exposured to BHIA or BHI media with or without Streptococcus sobrinus and served as different groups. After inoculating 10 weeks, their I_ corr ,E_ corr ,E_ tp through cyclic polarization curves were obtained through Corrview 2 corrosion analyses software;and their surface changes after electrochemical corrosion were observed by field emission scanning electron microscopy (FESEM).Results:The E_ corr of four alloys were decreased in presence of oral microorganism, and the declines were more remarkable in BHI with bacteria. SEM observation showed the pittings in their surface.The corrosion resistance in BHI without bacteria were significant increased than that in the blank control. Conclusion:Streptococcus sobrinus can promote the corrosion behavior of metal-ceramic alloys and the corrosion resistance is more worse in BHI than BHIA with bacteria.
2.Fabrication of Flower-Shaped Pt-Au-graphene Nanostructures and Their Application in Electrochemical Detection of Glucose
Yaojuan HU ; Wenji DU ; Changyun CHEN
Chinese Journal of Analytical Chemistry 2014;(9):1240-1244
The flower-shaped Pt-Au-graphene oxide ( GO ) nanostructures were synthesized by one-step electrochemical reduction method. The electrocatalytic activities of the nanostructures toward glucose oxidation were investigated by cyclic voltammetry. The results indicated that the nanocomposites exhibited a higher electrocatalytic activity than the Pt-Au nanoparticles. A glucose nonenzyme sensor could be easily developed with the use of the flower-shaped Pt-Au-GO nanostructure. The sensor exhibited low detection limit (4. 0 μmol/L), a wide and useful linear range (1. 0-25. 0 mmol/L), and high sensitivity (26. 3 μA cm-2 ( mmol)-1 ) . In addition, the sensor exhibited excellent reproducibility, stability and selectivity for the determination of glucose, and it could be used to analyze real samples.
3.Depression,anxiety,and health-related quality of life in adult epilepsy
Chunhui CHE ; Huapin HUANG ; Changyun LIU ; Fang JIANG ; Xiaochun CHEN
Chinese Journal of Neurology 2009;42(7):436-439
Objective To assess health-related quality of life and the mood disorder in adults with epilepsy,and to evaluate factors contributing to the quality of life.Methods Quality of life was measured by the Quality of Life in Epilepsy Inventory(QOLIE-31)and the World Health Organization Quality of Life Assessment-Bref(WHOQOL-BREF).Psychotic conditions were evaluated by Self-rating Depressive Scale (SDS)and Self-rating Anxious Seale(SAS).The multivariate analysis was used to assess the determinant factors.Results The study included 141 epilepsy patients in the teat group and 59 sex,age,and education matched normal controls. WHOQOL-BREF scores in the physical and psychological aspects were significantly lower in epilepsy patients(12.7 ±1.8 and 12.4±1.9,respectively)than those in the normal controls(15.1 ±2.3 and 13.9 ±1.9,respectively,t value were 11.75 and 8.625.both P<0.05).The survey reported that 57.4 % of the epilepsy patients suffered with depression.and 39.7 % anxiety.The patients with both anxiety and depression scored lower in all aspects in QOLIE survey except medical effect.Multivariate analysis showed that factors that effect the overall quality of life in order were anxiety.depression and disease duration.Conclusion Our results support that complications of anxiety and depression and long disease duration are key factors affecting the quality of life in epilepsy patients.
4.Behavior changes and expression of nitric oxide synthase mRNA of hypothalamus after sleep deprivation in rats
Changyun LIU ; Haiming WANG ; Jian CHEN ; Hongguang JI ; Jianguang ZHOU ;
Academic Journal of Second Military Medical University 1981;0(03):-
Objective: To study the effects of rapid eye movement sleep (REMS) deprivation on active behavior and the expression of mRNA coding for inducible nitric oxide synthase (iNOS) of hypothalamus in rats. Methods: The flower pot technique was adopted to deprive the REMS of Sprague Dawley rats for 24 h, 48 h and 72 h respectively. The active behavior of rats were examined by the open field test (OFT). The expression of mRNA coding for iNOS of hypothalamus in rats was assayed by reverse transcription polymerase chain reaction (RT PCR). Results: The OFT scores were significantly increased in rats subjected to 24 h and 48 h REMS deprivation ( P 0.05). There was no difference in the expression of iNOS mRNA among 24 h, 48 h REMS deprivation and the control groups, but the expression was significantly increased in 72 h REMS deprivation group ( P
5.Electrochemical Behavior and Determination of Pyridoxine Hydrochloride at Graphene-Carbon Nanotubes/Poly(nicotinic acid) Modified Electrode
Fengyun HE ; Jing YU ; Huan LIU ; Xiaoyan GU ; Pengpeng TANG ; Hong ZHOU ; Changyun CHEN ; Guofei LU
Chinese Journal of Analytical Chemistry 2014;(7):1039-1043
Graphene ( GN) and multiwalled carbon nanotubes ( MWCNT) composites were coated on glassy carbon electrode ( GCE ) and then poly ( nicotinic acid ) ( PNA ) was electrodeposited on the modified electrode. The electrochemical behavior of pyridoxine hydrochloride ( VB6 ) was investigated at the modified electrode by cyclic voltammetry ( CV ) and differential pulse voltammetry ( DPV ) . Results showed the oxidation current of VB6 at the GN-MWCNT/PNA/GCE was obviously larger than that at GCE, PNA/GCE and GN/MWCNT/GCE. The oxidation process of VB6 was an irreversible diffusion-controlled process involving one electron and two protons. The liner range between the peak current intensity of DPV and the concentration of VB6 was 0 . 05-200 μmol/L with a detection limit of 0 . 02 μmol/L ( S/N=3 ) . The modified electrode showed a good reproducibility with a relative standard deviation of 3 . 1% ( n=8 ) . The proposed method was applied to the analysis of vitamin B6 in vitamin B6 tablets and compound vitamin B tablets with recoveries between 96 . 1%-104 . 5%.
6.Preparation of an electrochemical immunosensor modified with graphene for detection of dienestrol in pork
Jie ZHANG ; Jun WU ; Chuanxian WANG ; Kefeng SHAO ; Changyun CHEN ; Bo ZHAO
Journal of China Pharmaceutical University 2015;46(6):683-688
An ultrasensitive electrochemical immunosensor modified with graphene and dienestrol(DE)was developed for the detection of dienestrol through indirect competition with K3Fe(CN)6 acting as the redox probes. The results revealed that under optimized conditions a calibration for DE was obtained with a linear range of 500-5 000 ng/mL and the detection limit was up to 0. 2 ng/mL, showing that the proposed electrochemical immunosensor had excellent sensitivity and wide detection range. The immunosensor was examined in real samples for the analysis of DE. A good recovery in the range of 83. 8%-97. 7% was obtained in pork samples.
7.Analysis of sepsis-related genes through weighted gene co-expression network
Changqin CHEN ; Li LI ; Changyun ZHAO ; Junhai ZHEN ; Jing YAN
Chinese Critical Care Medicine 2021;33(6):659-664
Objective:To identify the Key genes in the development of sepsis through weighted gene co-expression network analysis (WGCNA).Methods:The gene expression dataset GSE154918 was downloaded from the public database Gene Expression Omnibus (GEO) database, which containes data from 105 microarrays of 40 control cases, 12 cases of asymptomatic infection, 39 cases of sepsis, and 14 cases of follow-up sepsis. The R software was used to screen out differentially expressed genes (DEG) in sepsis, and the distributed access view integrated database (DAVID), search tool for retrieval of interacting neighbouring genes (STRING) and visualization software Cytoscape were used to perform gene function and pathway enrichment analysis, Protein-protein interaction (PPI) network analysis and key gene analysis to screen out the key genes in the development of sepsis.Results:Forty-six candidate genes were obtained by WGCNA and combined with DEG expression analysis, and these 46 genes were analyzed by gene ontology (GO) and Kyoto City Encyclopedia of Genes and Genomes (KEGG) pathway enrichment to obtain gene functions and involved signaling pathways. The PPI network was further constructed using the STRING database, and 5 key genes were selected by the PPI network visualization software Cytoscape, including the mast cell expressed membrane protein 1 gene (MCEMP1), the S100 calcium-binding protein A12 gene (S100A12), the adipokine resistance factor gene (RETN), the c-type lectin structural domain family 4 member gene (CLEC4D), and peroxisome proliferator-activated receptor gene (PPARG), and differential expression analysis of each of these 5 genes showed that the expression levels of the above 5 genes were significantly upregulated in sepsis patients compared with healthy controls.Conclusion:In this study, 5 key genes related to sepsis were screened by constructing WGCNA method, which may be potential candidate targets related to sepsis diagnosis and treatment.
8.Prevalence and molecular characteristics of Listeria monocytogenes in cooked products and its comparison with isolates from listeriosis cases.
Hong WANG ; Lijuan LUO ; Zhengdong ZHANG ; Jianping DENG ; Yan WANG ; Yimao MIAO ; Ling ZHANG ; Xi CHEN ; Xiang LIU ; Songsong SUN ; Bo XIAO ; Qun LI ; Changyun YE
Frontiers of Medicine 2018;12(1):104-112
This study aimed to investigate the prevalence and molecular characteristics of Listeria monocytogenes in cooked products in Zigong City, China. The overall occurrence of the L. monocytogenes in the ready-to-eat (RTE) shops and mutton restaurants surveyed was 16.2% (141/873). An occurrence of 13.5% was observed in RTE pork, 6.5% in RTE vegetables, and more than 24.0% in either cooked mutton or cooked haggis. Serotype 1/2b (45.4%), 1/2a (33.3%), and 1/2c (14.2%) were the predominant types. By comparing the clonal complexes (CCs) based on multilocus sequence typing (MLST) of the L. monocytogenes from cooked foods in Zigong City and 33 listeriosis cases from different districts of China, CC87, CC9, CC8, and CC3 were showed to be prevalent in cooked products and CC87 and CC3 were the first two frequent types in the 33 clinic-source strains. All CC87 stains harbored the newly reported Listeria pathogenicity island 4 (LIPI-4) gene fragment ptsA, and all CC3 strains possessed the Listeria pathogenicity island 3 (LIPI-3) gene fragment llsX. These may increase the occurrence of the strains belonging to CC87 and CC3 in listeriosis cases in China and also underline the risk of infection owing to the consumption of the cooked products from Zigong. ST619 (serotype 1/2b) harbored both llsX and ptsA, indicating a potential hypervirulent sequence type in Zigong.
China
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epidemiology
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Cooking
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Fast Foods
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microbiology
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Food Contamination
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Food Microbiology
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Humans
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Listeria monocytogenes
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genetics
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pathogenicity
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Listeriosis
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epidemiology
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microbiology
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Meat
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microbiology
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Multilocus Sequence Typing
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Prevalence
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Seasons