1.Application of ELISA kit for the detection of hepatitis E virus antigen in plasma donations
Weijin HUANG ; Aijing SONG ; Shan QIAO ; Chenyan ZHAO ; Xuerong JIA ; Yan ZHANG ; Youchun WANG
Chinese Journal of Microbiology and Immunology 2016;36(4):300-304
Objective To analyze the practicability of using ELISA kit for the detection of hepati-tis E virus antigen ( HEV-Ag) in plasma donations and Biomex HEV seroconversion panels. Methods The HEV-Ag positive samples were screened out from 36 340 donated blood plasma samples. Real-time fluores-cent PCR was performed for the detection of HEV RNA in HEV-Ag positive samples. The open reading frame 2 (ORF2) in HEV RNA was amplified by nested RT-PCR and the amplified products were confirmed by sequencing analysis. Phylogenetic tree was constructed for HEV genotyping. Five Biomex HEV serocon-version panels were used in this study for the detection of HEV-Ag, anti-HEV antibody and HEV RNA as well as the correlation analysis between HEV-Ag and HEV RNA. Results Twenty-six out of 36 340 plasma samples (0. 07%) were positive for HEV-Ag. Of the 26 samples, 25 samples were positive for HEV RNA as indicated by the results of nested RT-PCR and 23 positive samples were confirmed by sequencing analysis. The positive rate of HEV RNA in blood plasma donators was 1 ∶ 1 580 (0. 06%). There were 17 samples of genotype 1 (74%) and 6 samples of genotype 4 (26%) according to the phylogenetic tree analysis. All of the HEV-Ag positive samples were also positive for HEV RNA as indicated by the analysis of Biomex sero-conversion panels. HEV-Ag was consistent with the peak of the HEV RNA concentration. Conclusion A close relationship between HEV-Ag and HEV RNA was observed. HEV-Ag screening could be used as a measure to reduce the risk of HEV transmission by blood transfusion.
2.In vitro anti-influenza A virus H3N2 activity of lithium chloride
Hongkai ZHANG ; Jia ZANG ; Yanshi WU ; Yueping XING ; Zefeng DONG ; Xuerong YA ; Qiang SHEN
Chinese Journal of Experimental and Clinical Virology 2024;38(5):539-546
Objective:To analyze the activity of lithium chloride (LiCl) against influenza virus A (H3N2) in human non-small cell lung cancer cells (A549).Methods:Different concentrations of LiCl were incubated with A549 cells, and the cytopathic effect (CPE) was observed after 24 hours, and the effect of LiCl on cell activity was determined by CCK-8 method. After H3N2 (MOI=1) infected A549 cells, different concentrations of LiCl were added and incubated for 24 hours, and the viral load was measured by real time/reverse transcription quantitative polymerase chain reaction (RT-qPCR), and the CPE was observed, and the viral titer was determined. Different concentrations of LiCl were incubated with A549 at 37 ℃ and 5% CO 2 for 2 hours, virus was added and incubated for 24 hours, and the viral load was determined by RT-qPCR. LiCl, H3N2 and A549 were incubated at 4 ℃ for 1 hour, 35 ℃, 5% CO 2 for 24 hours, and viral load was determined by RT-qPCR. H3N2 and A549 were incubated at 4 ℃for 1 hour, then different concentrations of LiCl were added, incubated at 35 ℃ with 5% CO 2 for 24 hours, and the viral load was determined by RT-qPCR. After H3N2 infected A549 cells, different concentrations of LiCl were added and incubated for 24 hours, and the viral RNA load and viral titer of the supernatant and cells were measured, respectively, and then the corresponding ratios of the supernatant and the cells were calculated. After H3N2 (MOI=10) and BV (MOI=1) infected A549 cells, different concentrations of LiCl were added for 24 h, and the viral load was determined by RT-qPCR. Results:When the concentration of LiCl was<50 mmol/L, the cell viability of A549>90%. Different concentrations of LiCl could significantly reduce the viral load of H3N2 ( P<0.000 1), and the CPE of the LiCl treatment group was more dose-dependent than that of the control group. LiCl did not inhibit viral replication by affecting the cell itself; Different concentrations of LiCl significantly inhibited the entry of H3N2 into A549 ( P<0.000 1), and also had a certain inhibitory effect on the adsorption of A549 cells ( P<0.1). LiCl did not affect the assembly and release of H3N2 ( P>0.05), and it was also found that LiCl had a broad spectrum of antiviral effects against multiple influenza virus strains ( P<0.000 1). Conclusions:LiCl may exert antiviral effect by inhibiting the adsorption and entry of H3N2 into A549 cells and the replication of H3N2 in A549 cells, which provides a data reference for the prevention and treatment of viral infection by LiCl.
3.Investigation and Analysis of the Satisfaction and Confidence of the Students Majoring in Non-medical Interdisciplinary Subject in Our University
Hongyan WU ; Long WANG ; Xiong CHEN ; Minghu CEN ; Xing YANG ; Yan ZHANG ; Lei TANG ; Xuerong RAN ; Jia SUN
China Pharmacy 2017;28(27):3750-3754
OBJECTIVE:To improve the education quality of medical school,so as to provide the excellent human resources for the field of health.METHODS:2011-2014 grades of students majoring in pharmaceutical administration,pharmacy (marketing direction) and other non-medical interdisciplinary subjects were selected from our school to complete the questionnaire which conrained the questions about satisfaction and confidence for the major.The results of investigation were analyzed statistically.RESULTS:Totally 2 668 questionnaires were sent out,and 2 435 were recycled with effective recovery of 91.27%.Half of the students majoring in pharmaceutical administration or pharmacy (marketing) etc.were switched from other majors,and 38.40%(935 number) of the students wanted to change the major.The major of clinical,nursing and anesthesiology were most preferred by the students.Only 15.52% (378 number),26.32% (641 number) of the students thought that the school paid enough attention to them or had a positive attitude to their major,respectively.Students majoring in pharmacy (marketing) and health services administration had the lowest satisfaction about their major and the attention paid by the school (P<0.001).With the growth of grade,the satisfaction of students in various aspects had declined (P<0.001).Only 44.72% (1 089 number),34.25% (834 number) of the students had positive attitude towards the study or were optimistic about the future,respectively.With the growth of the grade,students' satisfaction in all aspects had declined (P<0.001).Compared to other students,freshman had more positive attitude towards the study or were more optimistic about the future (P<0.001).Besides,33.65% (491 number)of the students planning to work immediately after graduation lacked confidence to find a good job.CONCLUSIONS:The lower degree of satisfaction and confidence are found in the students majoring in non-medical interdisciplinary subject in the medical school,and this should be treated seriously by the school.
4.Changes and biological significance of ferroptosis in a mouse model of bloodstream infection induced by different bacteria
Zhibin ZHANG ; Chu WANG ; Ying HAN ; Jia WANG ; Junqing LYU ; Xuerong LIN ; Meng YUAN ; Shuchi HAN
Chinese Journal of Tissue Engineering Research 2024;28(28):4553-4558
BACKGROUND:It is of great significance to find new diagnostic markers of the disease and molecular targets for the treatment of the disease and the alleviation of organ injury.Ferroptosis is a newly discovered form of cell death.Overactivation of ferroptosis in animal models of sepsis is associated with the activation of inflammatory response and the injury of the liver,heart,kidney and other important organs,but the relationship between ferroptosis and bloodstream infection is not very clear. OBJECTIVE:To study the changes and biological significance of ferroptosis in a mouse model of blood stream infection induced by different bacteria. METHODS:Blood stream infection models induced by gram negative bacteria Escherichia coli,Klebsiella pneumoniae and gram positive bacteria Staphylococcus aureus and Enterococcus faecalis were established in SPF-grade ICR male mice,with 42 mice in each group.The mRNA expression levels of ferroptosis marker genes transferrin receptor 1 and glutathione peroxidase 4 in the liver,myocardium and kidney were detected at 0.5,1,3,6,12,24 and 48 hours after modeling.Another 18 SPF-grade ICR male mice were selected and randomly divided into dimethyl sulfoxide(DMSO)control group,DMSO+Klebsiella pneumoniae group,and Ferrostatin-1+Klebsiella pneumoniae group,with 6 mice in each group.In the latter two groups,animal models of Klebsiella pneumoniae bloodstream infection were established by tail vein injection of Klebsiella pneumoniae suspension,and 5 mg/kg Ferrostatin-1 and an equal dose of DMSO were given intraperitoneally 1 hour prior to the modeling of bloodstream infection,respectively.Serum levels of alanine aminotransferase,aspartate aminotransferase,blood creatinine,blood urea nitrogen,phosphocreatine kinase isoenzyme,lactate dehydrogenase,and mRNA expression levels of ferroptosis marker genes in various tissues were assayed at 6 hours after modeling. RESULTS AND CONCLUSION:After bloodstream infection modeling,the mRNA expression levels of transferrin receptor 1 in the liver,myocardium and kidney of bloodstream infection mice with different bacteria increased first and then decreased;and the mRNA expression level of glutathione peroxidase 4 decreased first,then increased,and reached the peak at 6 hours after modeling.The changes in transferrin receptor 1 and glutathione peroxidase 4 mRNA levels in bloodstream infection mice induced by gram-negative bacteria were more significant than those in blood stream infection mice induced by gram-positive bacteria,especially in bloodstream infection mice induced by Klebsiella pneumoniae.At 6 hours after bloodstream infection induced by Klebsiella pneumoniae,the levels of alanine aminotransferase,aspartate aminotransferase,serum creatinine,blood urea nitrogen,creatine phosphate kinase isoenzyme,lactate dehydrogenase in mice were significantly increased.Before modeling,Ferrostatin-1 intervention significantly reduced the levels of alanine aminotransferase,aspartate aminotransferase,serum creatinine,blood urea nitrogen,creatine phosphate kinase isoenzyme,and lactate dehydrogenase.All these findings indicate that the activation of ferroptosis in bloodstream infection mice induced by different bacteria is obvious,and the activation of ferroptosis in bloodstream infection mice induced by gram-negative bacteria is more obvious.Inhibition of iron death significantly attenuates liver,myocardial,and kidney injury in the mouse model of bloodstream infection induced by Klebsiella pneumoniae.
5.Biological role and related mechanism of autophagy in acute lung injury of hemorrhagic shock mice
Xuerong LIN ; Jia WANG ; Zhibin ZHANG ; Lijuan ZHU
Chinese Critical Care Medicine 2024;36(8):848-852
Objective:To study the biological role and related mechanism of autophagy in acute lung injury (ALI) of hemorrhagic shock mice.Methods:According to random number table method, wild-type male C57BL/6 mice were divided into control group, ALI group, rapamycin group and 3-methyladenine (3-MA) group, with 8 mice in each group. Light chain 3 (LC3) gene knockout mice with C57BL/6 background were divided into LC3 knockout group and LC3 knockout+ALI group, with 8 mice in each group. Control group, ALI group, LC3 knockout group, LC3 knockout+ALI group were intraperitoneally injected with 2 mL/kg normal saline, rapamycin group was intraperitoneally injected with 3 mg/kg autophagy activator rapamycin, 3-MA group was intraperitoneally injected with 15 mg/kg autophagy inhibitor 3-MA, all of which were given for 3 consecutive days. 2 hours after the last administration, the hemorrhagic shock induced ALI model was established. 24 hours after modeling, the lung index was calculated. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of lung tissue and lung injury score was performed. The expressions of autophagy genes LC3-Ⅱ/LC3-Ⅰ and Beclin-1 in lung tissue were detected by Western blotting. The contents of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and malondialdehyde (MDA) in lung tissue were detected according to the steps of the kit.Results:Compared with the control group, the lung tissue structure was destroyed and exudation increased, lung index, lung injury score, the expressions of LC3-Ⅱ/LC3-Ⅰ, Beclin-1, and the contents of TNF-α, IL-6 and MDA in lung tissue significantly increased in the ALI group. Compared with the ALI group, the structural damage and exudation of lung tissue were reduced in the rapamycin group, lung index, lung injury score and the contents of TNF-α, IL-6 and MDA in lung tissue decreased, while the expressions of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 in lung tissue increased [lung index: (7.56±0.39)% vs. (9.12±0.59)%, lung injury score: 3.04±0.58 vs. 9.32±2.14, TNF-α (ng/mg): 1.85±0.32 vs. 3.51±0.62, IL-6 (ng/mg): 1.61±0.32 vs. 2.52±0.44, MDA (nmol/mg): 1.03±0.16 vs. 1.88±0.24, LC3-Ⅱ/LC3-Ⅰ: 1.21±0.12 vs. 0.39±0.05, Beclin-1/β-actin: 1.10±0.12 vs. 0.58±0.06, all P < 0.05], while lung tissue structure damage was aggravated and exudation was further increased in the 3-MA group, lung index, lung injury score and the contents of TNF-α, IL-6 and MDA in lung tissue increased, the expressions of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 in lung tissue decreased [lung index: (10.44±0.62)% vs. (9.12±0.59)%, lung injury score: 11.59±2.28 vs. 9.32±2.14, TNF-α (ng/mg): 4.77±0.71 vs. 3.51±0.62, IL-6 (ng/mg): 3.44±0.52 vs. 2.52±0.44, MDA (nmol/mg): 2.71±0.42 vs. 1.88±0.24, LC3-Ⅱ/LC3-Ⅰ: 0.25±0.04 vs. 0.39±0.05, Beclin-1/β-actin: 0.21±0.03 vs. 0.58±0.06, all P < 0.05]. Lung index, lung injury score and the contents of TNF-α, IL-6 and MDA in lung tissue of LC3 knockout ALI mice were higher than those of wild-type ALI mice [lung index: (10.44±0.75)% vs. (9.12±0.59)%, lung injury score: 12.41±2.86 vs. 9.32±2.14, TNF-α (ng/mg): 4.85±0.72 vs. 3.51±0.62, IL-6 (ng/mg): 3.28±0.51 vs. 2.52±0.44, MDA (nmol/mg): 2.75±0.41 vs. 1.88±0.24, all P < 0.05]. Conclusion:Autophagy plays a protective role in ALI of hemorrhagic shock mice, and the related molecular mechanism is the inhibition of inflammatory response and oxidative stress response.
6.Production of L-2-aminobutyric acid from L-threonine using a trienzyme cascade.
Yan FU ; Junxuan ZHANG ; Xuerong FU ; Yuchen XIE ; Hongyu REN ; Jia LIU ; Xiulai CHEN ; Liming LIU
Chinese Journal of Biotechnology 2020;36(4):782-791
L-2-aminobutyric acid (L-ABA) is an important chemical raw material and chiral pharmaceutical intermediate. The aim of this study was to develop an efficient method for L-ABA production from L-threonine using a trienzyme cascade route with Threonine deaminase (TD) from Escherichia. coli, Leucine dehydrogenase (LDH) from Bacillus thuringiensis and Formate dehydrogenase (FDH) from Candida boidinii. In order to simplify the production process, the activity ratio of TD, LDH and FDH was 1:1:0.2 after combining different activity ratios in the system in vitro. The above ratio was achieved in the recombinant strain E. coli 3FT+L. Moreover, the transformation conditions were optimized. Finally, we achieved L-ABA production of 68.5 g/L with a conversion rate of 99.0% for 12 h in a 30-L bioreactor by whole-cell catalyst. The environmentally safe and efficient process route represents a promising strategy for large-scale L-ABA production in the future.
Aminobutyrates
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chemical synthesis
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Bacillus thuringiensis
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enzymology
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Candida
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enzymology
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Escherichia coli
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enzymology
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Formate Dehydrogenases
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metabolism
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Leucine Dehydrogenase
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metabolism
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Threonine
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metabolism
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Threonine Dehydratase
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metabolism