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Liu BF, Gao YZ. [The expression of neuraminidase-1 in Ewing sarcoma and its impact on sarcoma cell proliferation and migration]. Zhonghua Yi Xue Za Zhi 2023; 103:3287-3293. [PMID: 37926573 DOI: 10.3760/cma.j.cn112137-20230411-00580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/07/2023]
Abstract
Objective: To investigate the expression of neuraminidase-1 (NEU1) in Ewing sarcoma (ES) tissue and its effect on the proliferation and migration of ES cells. Methods: To obtain datasets of ES from the National Center for Biotechnology Information's High-Throughput Gene Expression Omnibus (GEO) for the analysis of NEU1 expression in ES; to acquire ES patient dataset from the International Cancer Genome Consortium (ICGC) database and apply Kaplan-Meier survival analysis to investigate the relationship between NEU1 and the prognosis of ES patients; adopting both univariate and multivariate Cox regression analysis to determine whether NEU1 is a prognostic factor for ES; adopting the Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation to analyze the potential mechanism of NEU1 in regulating the malignant biological behavior of ES; adopting the real-time fluorescence quantitative polynucleotide chain reaction (RT-qPCR) to verify the expression of NEU1 in the human bone marrow mesenchymal stem cells (hBMSC) and the ES cell line RD-ES; adopting the transfection technology to knock down the expression of NEU1 in ES cell lines and divide them into two groups: shRNA-NEU1 and shRNA-NC to explore the effects of altered NEU1 expression on ES malignant behavior; adopting the cell counting kit (CCK-8) and cell clone formation experiment to detect the proliferation ability of two groups of cells; adopting the scratch healing experiment to test the cell migration ability of the two groups. Results: We retrieved and analyzed data from the GEO database, including GSE17674 (44 ES tissues and 18 normal tissues) and GSE17679 (87 ES tissues and 18 normal tissues), and found that NEU1 expression was significantly higher in ES tissues compared to normal control tissues (P<0.001). The complete gene expression and clinical information of 56 ES patients obtained from the ICGC database revealed that the ES patients with high NEU1 expression (n=28) had a significantly lower overall survival rates at different time points compared to those with low NEU1 expression (n=28) (HR=2.830, 95%CI:1.324-6.051, P=0.005). Univariate analysis indicated that NEU1 could impact ES patient prognosis (HR=1.049, 95%CI: 1.008-1.092, P=0.019), and multivariate analysis further suggested that NEU1 could serve as a risk factor for ES prognosis (HR=1.087, 95%CI: 1.028-1.148, P=0.003). KEGG results show that MAPK signaling pathway and cell adhesion molecule signaling pathway were potential mechanisms regulating the malignant process of ES. The RT-qPCR results showed that the expression level of NEU1 in the RD-ES cell line is significantly higher than that in the control cell hBMSC (2 184.23±527.32 vs 1.00±0.08, P<0.001). The CCK-8 experiment results show that the proliferation of RD-ES cells in the NEU1 knockdown group was lower than that in the control group at 24, 48, and 72 hours (0.494±0.126 vs 0.696±0.118, 0.657±0.096 vs 1.142±0.182, 1.053±0.064 vs 1.980±0.146, all P<0.001). The results of single cell clone formation experiment show that the number of colony formation in the low expression NEU1 group was significantly lower than that in the control group (184.2±123.9 vs 362.8±78.0, P=0.021). The cell scratch healing experiment finds that the average scratch distance of the NEU1 knockdown group was significantly lower than that of the control group (19.6%±5.7% vs 56.0%±7.6%, P<0.001). Conclusion: NEU1 may be a prognostic factor in ES, and its abnormal expression in ES can affect the proliferation and migration ability of the ES cells, leading to poor prognosis in ES patients.
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Affiliation(s)
- B F Liu
- Department of Surgery of Spine and Spinal Cord, Henan Provincial People's Hospital, Henan Province Intelligent Orthopedic Technology Innovation and Transformation International Joint Laboratory, Henan Key Laboratory for Intelligent Precision Orthopedics, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou 450003, China
| | - Y Z Gao
- Department of Surgery of Spine and Spinal Cord, Henan Provincial People's Hospital, Henan Province Intelligent Orthopedic Technology Innovation and Transformation International Joint Laboratory, Henan Key Laboratory for Intelligent Precision Orthopedics, People's Hospital of Zhengzhou University, People's Hospital of Henan University, Zhengzhou 450003, China
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Zeng Q, Wei WB, Liu J, Liu BF, Liu HL. [Construction of Tianjin occupational disease prevention and control ability assessment system based on Delphi method]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2023; 41:871-875. [PMID: 37935558 DOI: 10.3760/cma.j.cn121094-20220606-00300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
Objective: To establish a systematic, scientific, reasonable, feasible and reliable evaluation system for occupational disease prevention and control capability, in order to provide reference for occupational disease prevention and control work in Tianjin City. Methods: In August 2022, literature review was conducted to propose indicators for the evaluation system. Two rounds of anonymous consultation with occupational health experts were conducted using the Delphi method to form expert opinions. According to the boundary value method and expert opinions, eliminate, screen, and modify the evaluation system indicators to ultimately determine the system indicators. Use Cronbach's alpha to test the reliability of the system indicators and form a Tianjin occupational disease prevention and control capability evaluation system. Results: It showed that the effective response rates of the two rounds of consultation conducted by experts in this study were 92.3% and 100.0%, respectively. The expert authority coefficients were 0.84 and 0.82, respectively. The Kendall coordination coefficient was tested for differences, and the differences were statistically significant (P<0.05). The Tianjin occupational disease prevention and control capability evaluation system includes 7 primary indicators, 17 secondary indicators, and 54 tertiary indicators. The Cronbach's alpha of the primary, second, third level indicators and all indicators were 0.91, 0.98, 0.98, 0.98 (>0.7) . Conclusion: The preliminary evaluation system for occupational disease prevention and control capacity in Tianjin City has been established, providing a reference basis for the investigation of occupational disease prevention and control capacity in Tianjin City.
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Affiliation(s)
- Q Zeng
- Institute for Occupational Health, Tianjin Center for Disease Control and Prevention, Tianjin 300011, China School of Public Health, Tianjin Medical University, Tianjin 300070, China
| | - W B Wei
- School of Public Health, Tianjin Medical University, Tianjin 300070, China Medical Record Statistics Department of Shaoxing People's Hospital, Shaoxing 312000, China
| | - J Liu
- Institute for Occupational Health, Tianjin Center for Disease Control and Prevention, Tianjin 300011, China
| | - B F Liu
- Institute for Occupational Health, Tianjin Center for Disease Control and Prevention, Tianjin 300011, China
| | - H L Liu
- School of Public Health, Tianjin Medical University, Tianjin 300070, China Tianjin Municipal Health Commission Science and Education Office, Tianjin 300070, China
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Cheng T, Han TY, Liu BF, Pan P, Lai Q, Yu H, Cao Y. Use of Modified Balthazar Grades for the Early Prediction of Acute Pancreatitis Severity in the Emergency Department. Int J Gen Med 2022; 15:1111-1119. [PMID: 35153503 PMCID: PMC8824293 DOI: 10.2147/ijgm.s350383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 01/19/2022] [Indexed: 11/23/2022] Open
Abstract
Objective To develop a new approach based on Balthazar grades of acute pancreatitis (AP) and to assess this modified method as a tool for the early prediction of AP severity in the emergency department (ED). Methods Data pertaining to AP patients ≥18 years old that had undergone computed tomography (CT) scanning within 24 h following ED admission between January 1, 2017 and September 30, 2017 were retrospectively analyzed. Patients were separated into two groups based on the length of time between the onset of their AP symptoms and the completion of CT scanning (Group 1: <72 h; Group 2: ≥72 h). Modified Balthazar grades for these patients were then assessed, with the concordance between these modified grades and the 2012 revised Atlanta classification being assessed using the Kappa (κ) statistic. The modified grade with the largest κ value was evaluated based on performance traits including Harrell’s concordance index (C-index), area under the receiver operating characteristic curve (AUC) analyses, calibration curves, and decision curve analyses (DCA) in comparison with bedside index for severity in AP (BISAP) scores. Results In total, 372 patients were included in the present analysis. These patients were regraded according to six methods, with the method yielding the largest κ value consisting of regraded Balthazar grades A–C, D, and E, respectively, corresponding to mild, moderate, and severe AP. The κ values for this method were 0.786 (95% CI, 0.706–0.853) in Group 1 and 0.907 (95% CI, 0.842–0.955) in Group 2, exhibiting nearly complete agreement with the latest Atlanta classification of AP. AUROC values for these modified Balthazar grades when used to predict SAP were significantly higher than those for BISAP scores in Group 1, Group 2, and the overall cohort (P < 0.05). The DCA curves for Group 1, Group 2, and the overall patient cohort exhibited substantial net benefits when using these modified grades across a range of POFs relative to BISAP scores. The calibration curve for this modified approach to predicting POF in AP patients revealed good agreement in this cohort. Conclusion Modified Balthazar grades exhibited substantial to near-total agreement with the 2012 revised Atlanta classification of AP patients, and this modified method can thus be used for the early prediction of AP severity in the ED.
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Affiliation(s)
- Tao Cheng
- Emergency Department, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
- Laboratory of Emergency Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Tian-Yong Han
- Emergency Department, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
- Laboratory of Emergency Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Bo-Fu Liu
- Emergency Department, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
- Laboratory of Emergency Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Pan Pan
- Emergency Department, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
- Laboratory of Emergency Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Qiang Lai
- Emergency Department, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
- Laboratory of Emergency Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Haifang Yu
- Emergency Department, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
- Laboratory of Emergency Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
| | - Yu Cao
- Emergency Department, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
- Laboratory of Emergency Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan, People’s Republic of China
- Correspondence: Yu Cao, Emergency Department of West China Hospital and Laboratory of Emergency Medicine of West China Hospital, Sichuan University, 37 Guoxue Road, Chengdu, 610041, Sichuan, People’s Republic of China, Tel +86-28-85422288, Email
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Abstract
Observations of black hole X-ray binaries and active galactic nuclei indicate that the accretion flows around black holes are composed of hot and cold gas, which have been theoretically described in terms of either a hot geometrically thick corona lying above and below a cold geometrically thin disk or an inner advection dominated accretion flow connected to an outer thin disk. This article reviews the accretion flows around black holes, with an emphasis on the physics that determines the configuration of hot and cold accreting gas, and how the configuration varies with the accretion rate and thereby produces various luminosity and spectra.
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Affiliation(s)
- B F Liu
- Key Laboratory of Space Astronomy and Technology, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China.,School of Astronomy and Space Sciences, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China
| | - Erlin Qiao
- Key Laboratory of Space Astronomy and Technology, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China.,School of Astronomy and Space Sciences, University of Chinese Academy of Sciences, 19A Yuquan Road, Beijing 100049, China
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Cheng T, Liu BF, Han TY, Gu ZH, Pan P, Yu H. Effectiveness and safety of proton pump inhibitors for treating acute pancreatitis: A protocol for systematic review and meta analysis. Medicine (Baltimore) 2021; 100:e24808. [PMID: 33663099 PMCID: PMC7909174 DOI: 10.1097/md.0000000000024808] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 01/29/2021] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Previous studies have showed that anti-acid therapy with proton pump inhibitors (PPIs) can inhibit pancreatic secretion and it may be used in treating acute pancreatitis (AP). But at present, there is no systematic reviews for the evidence and the therapeutic effectiveness and safety of anti-acid therapy with PPIs in AP were not unclear. Therefore, we will undertake a systematic review of the literature to summarize previous evidence regarding this topic, in order to clarify the effectiveness and safety of anti-acid therapy with PPIs in AP. METHODS We will search the EMBASE, WANFANG DATA, Web of Knowledge, China National Knowledge Infrastructure, PubMed, ClinicalTrials.gov and Cochrane Library from inception to June 30,2021 to retrieve relevant studies using the search strategy: ("Proton pump inhibitors" OR "PPI" OR "PPIs" OR "Omeprazole" OR "Tenatoprazole" OR "Pantoprazole" OR "acid suppression therapy" OR "acid suppression drugs") AND ("pancreatitis" OR "pancreatitides"). Two authors independently judged study eligibility and extracted data. Heterogeneity will be examined by computing the Q statistic and I2 statistic. RESULTS This study assessed the efficiency and safety of proton pump inhibitors for treating acute pancreatitis. CONCLUSIONS This study will provide reliable evidence-based evidence for the clinical application of PPIs for treating AP. ETHICS AND DISSEMINATION Ethical approval is unnecessary as this protocol is only for systematic review and does not involve privacy data. The findings of this study will be disseminated electronically through a peer-review publication or presented at a relevant conference.
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Affiliation(s)
- Tao Cheng
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | - Bo-Fu Liu
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | | | - Zhi-Han Gu
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | - Pan Pan
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
| | - Haifang Yu
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
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6
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Cheng T, Liu BF, Han TY, Gu ZH, Pan P, Haifang Y. Effectiveness and safety of Liuhedan for treating acute pancreatitis: A protocol for systematic review and meta analysis. Medicine (Baltimore) 2021; 100:e24863. [PMID: 33663109 PMCID: PMC7909230 DOI: 10.1097/md.0000000000024863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 01/29/2021] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Liuhedan is a famous traditional Chinese medicine (TCM) formula used to treat acute pancreatitis (AP) in China. However, there is no systematic reviews for the evidence and the therapeutic effectiveness and safety of Liuhedan for treating AP. The aim of this study is to summarize previous evidence, assessing the efficacy and safety of Liuhedan in the treatment of AP. METHODS We will search the EMBASE, WANFANG DATA, Web of Knowledge, CNKI, PubMed, ClinicalTrials.gov and Cochrane Library from inception to June 30, 2021 to retrieve relevant studies using the search strategy: ("Liuhedan" OR "Liuhe Pill" OR "Liu-He-Dan") AND ("pancreatitis" OR "pancreatitides"). Two authors independently judged study eligibility and extracted data. Heterogeneity will be examined by computing the Q statistic and I2 statistic. RESULTS This study assessed the efficiency and safety of Liuhedan for treating acute pancreatitis. CONCLUSIONS This study will provide reliable evidence-based evidence for the clinical application of Liuhedan for treating AP. ETHICS AND DISSEMINATION Ethical approval is unnecessary as this protocol is only for systematic review and does not involve privacy data. The findings of this study will be disseminated electronically through a peer-review publication or presented at a relevant conference.
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Affiliation(s)
- Tao Cheng
- Department of Emergency Medicine
- Laboratory of Emergency Medicine, West China Hospital
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | - Bo-Fu Liu
- Department of Emergency Medicine
- Laboratory of Emergency Medicine, West China Hospital
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | | | - Zhi-Han Gu
- Department of Emergency Medicine
- Laboratory of Emergency Medicine, West China Hospital
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | - Pan Pan
- Department of Emergency Medicine
- Laboratory of Emergency Medicine, West China Hospital
| | - Yu Haifang
- Department of Emergency Medicine
- Laboratory of Emergency Medicine, West China Hospital
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
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Cheng T, Xiao BJ, Liu BF, Han TY, Yu HF. Efficiency of free thyroxine in predicting severity and mortality of patients with acute pancreatitis: A protocol for systematic review and meta-analysis. Medicine (Baltimore) 2021; 100:e24809. [PMID: 33607844 PMCID: PMC7899895 DOI: 10.1097/md.0000000000024809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Previous studies suggest that free thyroxine may be used as a severity indicator of patients with acute pancreatitis (AP) in emergency department, helping determine the differential care of AP. However, there are no systematic reviews and the association between free thyroxine and AP is still not completely understood. Therefore, we will undertake a systematic review of the literature to summarize previous evidence regarding this topic, in order to clarify whether free thyroxine can help us pick out the mild AP cases. METHODS : We will search the EMBASE, Web of Knowledge, PubMed, ClinicalTrials.gov, and Cochrane Library from inception to Mar 2021 to retrieve relevant studies using the search strategy: ("free thyroxine") AND (pancreatitis OR pancreatitides). Two authors independently judged study eligibility and extracted data. Heterogeneity will be examined by computing the Q statistic and I2 statistic. RESULTS : This study proved the efficiency of free thyroxine in predicting the severity of patients with AP. CONCLUSIONS : This study will provide reliable evidence-based evidence for the clinical application of free thyroxine predicting the severity of patients with AP. ETHICS AND DISSEMINATION Ethical approval is unnecessary as this protocol is only for systematic review and does not involve privacy data. The findings of this study will be disseminated electronically through a peer-review publication or presented at a relevant conference.
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Affiliation(s)
- Tao Cheng
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | | | - Bo-Fu Liu
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | | | - Hai-Fang Yu
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
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8
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Cheng T, Liu BF, Han TY, Pan P, Liu JZ, Yu H. Efficiency of red cell distribution width in predicting severity and mortality of patients with acute pancreatitis: A protocol for systematic review and meta-analysis. Medicine (Baltimore) 2021; 100:e24658. [PMID: 33578595 PMCID: PMC10545405 DOI: 10.1097/md.0000000000024658] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 01/15/2021] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Previous studies have showed that red cell distribution width (RDW) may be an inflammatory status, and it may be used to predict prognosis of acute pancreatitis (AP). However, there are no systematic reviews for the evidence, and the association between RDW and AP is still not completely understood. Therefore, we will undertake a systematic review of the literature to summarize previous evidence regarding this topic, in order to clarify the value of RDW predicting prognosis of patients with AP. METHODS We will search EMBASE, Web of Knowledge, PubMed, ClinicalTrials.gov and Cochrane Library from their inception to Mar 2021 to retrieve relevant studies. Two authors independently judged study eligibility and extracted data. Heterogeneity will be examined by computing the Q statistic and I2 statistic. RESULTS This study proved the Efficiency of RDW in predicting mortality and severity of patients with AP. And provided easy method for clinical evaluation for AP patients. CONCLUSIONS The findings of this systematic review will show the value of RDW predicting prognosis of patients with AP. ETHICS AND DISSEMINATION Ethical approval is unnecessary as this protocol is only for systematic review and does not involve privacy data. The findings of this study will be disseminated electronically through a peer-review publication or presented at a relevant conference.
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Affiliation(s)
- Tao Cheng
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | - Bo-Fu Liu
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
| | | | - Pan Pan
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
| | | | - Haifang Yu
- Emergency Department
- Laboratory of Emergency Medicine, West China Hospital, Sichuan University
- Disaster Medical Center, Sichuan University, Chengdu, Sichuan, China
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9
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Yan H, Aizhan R, Lu YY, Li X, Wang X, Yi YL, Shan YY, Liu BF, Zhou Y, Lü X. A novel bacteriocin BM1029: physicochemical characterization, antibacterial modes and application. J Appl Microbiol 2020; 130:755-768. [PMID: 32749036 DOI: 10.1111/jam.14809] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 06/15/2020] [Accepted: 07/22/2020] [Indexed: 12/28/2022]
Abstract
AIM Bacteriocins with antimicrobial activity are considered as potential natural bio-preservatives to control the growth of food spoilage bacteria. The aim of this work was to characterize a novel bacteriocin BM1029 discovered from Lactobacillus crustorum MN047 and evaluate its antibacterial mechanism. METHODS AND RESULTS Bacteriocin BM1029 was purified by cation-exchange chromatography and reversed-phase chromatography. Antibacterial activity assay showed that BM1029 is antagonistic against both Gram-positive and Gram-negative bacteria. Furthermore, it was found that BM1029 showed low haemolysis with high stability to the pretreatment with different temperatures, pH and surfactants. Moreover electron microscopy and flow cytometry suggested that BM1029 inhibit indicator strains by damaging the cell envelope integrity. Cell cycle assay suggested that BM1029 arrested cell cycle in R-phase. CONCLUSION The novel bacteriocin BM1029 showed high bactericidal activity against Escherichia coli and Staphylococcus aureus through a cell envelope-associated mechanism. SIGNIFICANCE AND IMPACT OF THE STUDY Application of BM1029 inhibited the growth of indicator strains on beef meat storage at 4°C suggesting that this bacteriocin is promising to be used as a novel preservative in food processing and preservation.
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Affiliation(s)
- H Yan
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - R Aizhan
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Y Y Lu
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - X Li
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - X Wang
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Y L Yi
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Y Y Shan
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - B F Liu
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - Y Zhou
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
| | - X Lü
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
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Zhang SX, Li J, Zhou P, Na JR, Liu BF, Zheng XW, Cao XY, Tong AR, Gao XF, Wang XQ, Xie F, Xu L, Ma GR, Zhou W. [The analysis of clinical characteristics of 34 novel coronavirus pneumonia cases in Ningxia Hui autonomous region]. Zhonghua Jie He He Hu Xi Za Zhi 2020; 43:431-436. [PMID: 32450631 DOI: 10.3760/cma.j.cn112147-20200219-00121] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To analyze the clinical characteristics of 34 COVID-19 cases and to provide the basis for the prevention and control of the epidemic disease. Methods: Thirty-four COVID-19 patients diagnosed with RT-PCR in the isolation ward of the Fourth People's Hospital of Ningxia Hui autonomous region (infectious diseases hospital) from the January 22 to February 4, 2020 were selected as the research subjects. The clinical data were collected. Excel was used to describe the relationship between clinical classification and age distribution, contact history and date of onset. SPSS 25.0 statistical software was used for analysis. The general information, clinical symptoms, blood test, virus nucleic acid test results, epidemiology, CT imaging, treatment and prognosis were analyzed. Results: There were 5 mild cases (5/34), 24 ordinary cases (24/34), 5 severe cases (5/34). The elderly was more common in severe patients. The main clinical symptoms were fever (27/34)and dry cough(26/34). The peripheral blood showed normal or decreased leukocyte count (33/34), decreased lymphocyte count (12/34). The increase of C-reactive protein (CRP) and D-dimer was related to the severity of the disease. Some patients had mild liver and kidney damage. Six patients were diagnosed through 3 or more times of nucleic acid tests. Sixteen cases had Wuhan related history,13 cases were close contacts, 5 cases had no confirmed route. The clustered infections were found in 6 families. In typical cases, CT showed single or multiple patchy ground glass shadow with thickening of interlobular septum. In severe cases, diffuse lesions of both lungs were found, with ground glass shadow, consolidation shadow and strip shadow coexisting. Thirty-four patients were treated with interferon-α and Lopinavir/Ritonavir with good prognosis. Conclusions: The clinical characteristics of COVID-19 were similar to that of general viral pneumonia but with strong infectivity. Close contact and family aggregation caused disease outbreaks. COVID-19 could not be excluded if two nucleic acid tests were negative and high-resolution CT was helpful for differential diagnosis. Early detection, early isolation, early diagnosis and early treatment are important for good prognosis. The effectiveness of antiviral drugs needs to be further verified.
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Affiliation(s)
- S X Zhang
- Department of Respiratory and Critical Care Medicine, The General Hospital of Ningxia Medical University, Yinchuan, 750004, China
| | - J Li
- Department of Internal Medicine, The Fourth People's Hospital of Ningxia Hui Autonomous Region, Yinchuan, 750021, China
| | - P Zhou
- Department of Radiology, The Fourth People's Hospital of Ningxia Hui Autonomous Region, Yinchuan, 750021, China
| | - J R Na
- Department of Respiratory and Critical Care Medicine, The General Hospital of Ningxia Medical University, Yinchuan, 750004, China
| | - B F Liu
- Intensive Care Unit, The Fourth People's Hospital of Ningxia Hui Autonomous Region, Yinchuan, 750021, China
| | - X W Zheng
- Department of Respiratory and Critical Care Medicine, The General Hospital of Ningxia Medical University, Yinchuan, 750004, China
| | - X Y Cao
- Intensive Care Unit, General Hospital of Ningxia Medical University, Yinchuan, 750004, China
| | - A R Tong
- Department of traditional Chinese medicine, Ningxia Institute of traditional Chinese medicine, Yinchuan, 750021, China
| | - X F Gao
- Intensive Care Unit, The First People's Hospital of Ningxia Hui Autonomous Region, Yinchuan, 750004, China
| | - X Q Wang
- Intensive Care Unit, General Hospital of Ningxia Medical University, Yinchuan, 750004, China
| | - F Xie
- Intensive Care Unit, General Hospital of Ningxia Medical University, Yinchuan, 750004, China
| | - L Xu
- Intensive Care Unit, The Fourth People's Hospital of Ningxia Hui Autonomous Region, Yinchuan, 750021, China
| | - G R Ma
- Department of Respiratory, The Fourth People's Hospital of Ningxia Hui Autonomous Region, Yinchuan, 750021, China
| | - W Zhou
- Department of Respiratory and Critical Care Medicine, The General Hospital of Ningxia Medical University, Yinchuan, 750004, China
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11
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Fan L, Zhang M, Liu BF, Liu J, Tang HJ, Zhu BL, Miao RM, Zhang MB, Fang XL, Fang JY, Zhao SL, Zeng Q, Gu Q. [Effects of p-Phenylene diamine on liver and kidney functions of occupational exposed workers]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2019; 36:923-926. [PMID: 30812082 DOI: 10.3760/cma.j.issn.1001-9391.2018.12.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To study the effect of p-phenylenediamine (PPD) on liver and kidney function in occupational exposed workers. Methods: Workers in a hair dye production enterprise which used p-phenylenediamine as a raw material for production were selected as the main research population. Then we conducted a questionnaire survey on the basic conditions of workers and conducted occupational health checkups on general health status, liver and kidney function. Occupational health examination assessment results were tested in Taizhou Cancer Hospital. All data was built using EpiData 3.1 software, and statistical analysis was performed using software SPSS 20.0. Results: The liver function indicators including direct bilirubin, prealbumin, total protein, and white protein, globulin, aspartate aminotransferase, glutamyl transpeptidase, and total bilirubin in the workers exposed to high concentration of PPD were at high normal values, and these indicators were significantly different from low PPD concentration group (P<0.05) . The serum creatinine and serum uric acid in the renal function index were significantly higher in workers exposed to PPD than in workers exposed to low concentrations and in the control group (P<0.05) . Conclusion: Occupational exposed to PPD may have a hazard to the workers' liver and kidney function. Long-term occupational exposure to PPD may lead to increased cumulative exposure of workers, which may cause potential chronic liver and kidney damage in occupationally exposed populations.
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Affiliation(s)
- L Fan
- Tianjin Centers for Disease Control and Prevention, Tianjin 300011, China
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12
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Liu BF, Liu J, Han C, Guo XX, Zeng Q. [Evaluation uncertainty of power frequency electric field for a Power Project in inner Mongolia]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2019; 36:704-706. [PMID: 30419684 DOI: 10.3760/cma.j.issn.1001-9391.2018.09.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: With the measurement and uncertainty analysis of the power frequency electric field of the main transformer in the power station, the source of uncertainty, its quantitative calculation, the synthetic assessment method and the reporting method of the measurement results are described to ensure the reliability of the power frequency electric field measurement data. Methods: Referring to the "Measurement of power frequency electric field in the workplace" (GBZ/T189.3-2007) , "Labour environment monitoring technological specification of electric power industry Partt7: Monitoring of power frequency electromagnetic fields" (DL/T 799.7-2010) and "Evaluation and Expression of Uncertainty in Measurement" (JJF 1059.1-2012) , the uncertainty of power frequency electric field measurement data of the main transformer of a power plant was analyzed and the extended uncertainty was obtained. Results: The main source of the uncertainty of power frequency electric field measurement was the measurement of repetitive operation, and the expanded uncertainty of power frequency electric field was 0.09 kV/m. Conclusion: When reporting the results of power frequency electric field measurement, the measurement uncertainty should be used simultaneously to quantify the quality of the measurement results. This method has strong practicability and operability, which can meet the requirements of uncertainty evaluation of power frequency electric field measurement results.
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Affiliation(s)
- B F Liu
- Institute of Occupational Disease Prevention and Control, Tianjin Centers for Disease Control and Prevention, Tianjin 300011, China
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13
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Liu MM, Liu BF, Zhang J, Liu J, Zhang M, Zhao SL. [Determination of p-Phenylene diamine in workplace air by elution solution-liquid chromatography]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2019; 36:700-703. [PMID: 30419683 DOI: 10.3760/cma.j.issn.1001-9391.2018.09.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To establish a elution solution-liquid chromatography method for determination of p-Phenylene diamine (PPD) in workplace air. Methods: p-Phenylene diamine (PPD) in the air of workplace was collected with glass fiber filters coated with dilute sulfuric acid and extracted with an aqueous EDTA solution. The target toxicant was separated with the C(18) column and analyzed with UV detector, identified by retention time, and quantified by peak area. Results: The linear range of PPD in the air of workplace was 2.00~10.00 μg/ml, with a correlation coefficient of 0.999 96. The limit of detection was 0.07 μg/ml. The lower limit of quantification was 0.23 μg/ml. The minimum detectable concentration was 0.003 1 mg/m(3) under 45.0 L sampling volume and 2.0 ml extraction solution volume. The within-run precision of different PPD concentrations was 0.15%~2.3% and the between-run precisions was 1.4%~2.6%; The extraction efficiencies was 91.4%~95.4%; The average collection efficiencies was 96.6%; The samples could be stored for 7 days isolation of air. The potential coexistence of m-Phenylene diamine and o-Phenylene diamine with p-Phenylene diamine (PPD) in the air did not interfere with the results of determination. Conclusion: This method has high sensitivity, precision, accuracy and lower limit of detection and it is applicable for determination of p-Phenylene diamine (PPD) in workplace air.
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Affiliation(s)
- M M Liu
- Institute of occupational Disease control and Prevention, Tianjin Centers for Disease Control and Prevention, Tianjin 300011, China
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14
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Wei W, Xie Y, Lai SC, Liu BF, He YR, Hu H, Cao Y. Benefits of anti-inflammatory therapy in the treatment of ischemia/reperfusion injury in the renal microvascular endothelium of rats with return of spontaneous circulation. Mol Med Rep 2017; 15:4231-4238. [DOI: 10.3892/mmr.2017.6548] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 02/14/2017] [Indexed: 11/05/2022] Open
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15
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He YR, Hu H, Jiang YW, Hu JF, Li XH, Yao YC, Zhu D, Liu BF, Peng LY, Wang JQ, Wang JQ. [Multivariate factors analysis on length of stay in Lushan earthquake victims]. Sichuan Da Xue Xue Bao Yi Xue Ban 2014; 45:633-636. [PMID: 25286690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To clarify the factors associate with the length of stay (LOS) in Lushan Earthquake victims. METHODS We retrospectively analyzed the medical information of 263 traumatic patients admitted to West China Hospital, Sichuan University after the Lushan Earthquake. Ten variables extracted for the analysis, including gender, age, injuried time, multiple injury, infection, comorbidities, Injury Severity Score (ISS), Revised Trauma Score (RTS) CRAMS score, and Prehospital Index (PHI). Univariable analysis using multiple stepwise regression analysis was performed to identify the factors associated with extended LOS. RESULTS Infection, ISS score, and Pre-hospital Time were associated with extended LOS, and infection was the most weighted factor. The regression equation is: LOS (h) = 498.36 + 671.41 x Infection + 43.87 x ISS score - 5.12 x Pre-hospital Time. CONCLUSION This study demonstrated that trauma patients with infections and high ISS scores were at increased risk for extended LOS and pre-hospital time decreased the risk.
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Ma J, Cui FZ, Liu BF, Xu QY. Atomic force and confocal microscopy for the study of cortical cells cultured on silicon wafers. J Mater Sci Mater Med 2007; 18:851-6. [PMID: 17206523 DOI: 10.1007/s10856-006-0071-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2005] [Accepted: 01/17/2006] [Indexed: 05/13/2023]
Abstract
The primary cortical cells were selected as a model to study the adherence and neural network development on chemically roughened silicon substrates without any coatings using confocal laser scanning microscopy (CLSM) and atomic force microscopy (AFM). The silicon substrates have a nano-range roughness (RMS) achieved by chemical etching using hydrofluoric (HF) acid. After 7 days of culturing, the neurons were observed to connect together and form dense neural networks. Furthermore, AFM results revealed that some porous structures at a few micrometer range existed between the neuron cells and the silicon substrates. It is suggested that the porous structures are made of extracellular matrix (ECM) components and play an important role in the neuronal adhesion and neurite outgrowth on the inert silicon wafers.
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Affiliation(s)
- J Ma
- Department of Material Science and Engineering, Tsinghua University, Beijing, PR China
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17
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Abstract
Protein-ligand docking can be formulated as a parameter optimization problem associated with an accurate scoring function, which aims to identify the translation, orientation, and conformation of a docked ligand with the lowest energy. The parameter optimization problem for highly flexible ligands with many rotatable bonds is more difficult than that for less flexible ligands using genetic algorithm (GA)-based approaches, due to the large numbers of parameters and high correlations among these parameters. This investigation presents a novel optimization algorithm SODOCK based on particle swarm optimization (PSO) for solving flexible protein-ligand docking problems. To improve efficiency and robustness of PSO, an efficient local search strategy is incorporated into SODOCK. The implementation of SODOCK adopts the environment and energy function of AutoDock 3.05. Computer simulation results reveal that SODOCK is superior to the Lamarckian genetic algorithm (LGA) of AutoDock, in terms of convergence performance, robustness, and obtained energy, especially for highly flexible ligands. The results also reveal that PSO is more suitable than the conventional GA in dealing with flexible docking problems with high correlations among parameters. This investigation also compared SODOCK with four state-of-the-art docking methods, namely GOLD 1.2, DOCK 4.0, FlexX 1.8, and LGA of AutoDock 3.05. SODOCK obtained the smallest RMSD in 19 of 37 cases. The average 2.29 A of the 37 RMSD values of SODOCK was better than those of other docking programs, which were all above 3.0 A.
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Affiliation(s)
- Hung-Ming Chen
- Department of Information Engineering and Computer Science, Feng Chia University, Taichung, Taiwan
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Liu BF, Ma J, Xu QY, Cui FZ. Regulation of charged groups and laminin patterns for selective neuronal adhesion. Colloids Surf B Biointerfaces 2006; 53:175-8. [PMID: 17046215 DOI: 10.1016/j.colsurfb.2006.08.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2006] [Accepted: 08/28/2006] [Indexed: 11/16/2022]
Abstract
Primary neuronal cultures on substrates patterned with extracellular matrix proteins such as laminin have yielded much information regarding the physiological characteristics of neuronal cells in vitro. Surface charge also influences neuronal adherence, and a positive charge can have stimulatory effects. The attraction between laminin patterns and polycation films are of interest in the study of neuronal adhesion. We cultured primary hippocampal neurons on poly(ethylenimine) (PEI) films with laminin grids and evaluated their viability and morphology by means of fluorescent microscopy after 5-7 days. The results showed that the neurons did not form networks on the laminin grids. It is inferred that the PEI films were more favourable for neuronal adhesion than the laminin grid.
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Affiliation(s)
- B F Liu
- Beijing Institute for Neuroscience, Capital Medical University, Beijing center for Neural Regeneration & Repair, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Beijing 100069, PR China
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Ma J, Liu BF, Xu QY, Cui FZ. AFM study of hippocampal cells cultured on silicon wafers with nano-scale surface topograph. Colloids Surf B Biointerfaces 2005; 44:152-7. [PMID: 16054346 DOI: 10.1016/j.colsurfb.2005.06.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2005] [Revised: 05/19/2005] [Accepted: 06/18/2005] [Indexed: 11/21/2022]
Abstract
The rat hippocampal cells were selected as model to study the interaction between the neural cells and silicon substrates using atomic force microscopy (AFM). The hippocampal cells show tight adherence on silicon wafers with nano-scale surface topograph. The lateral friction force investigated by AFM shows significant increase on the boundary around the cellular body. It is considered to relate to the cytoskeleton and cellular secretions. After ultrasonic wash in ethanol and acetone step by step, the surface of silicon wafers was observed by AFM sequentially. We have found that the culture leftovers form tight porous networks and a monolayer on the silicon wafers. It is concluded that the leftovers overspreading on the silicon substrates are the base of cell adherence on such smooth inert surfaces.
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Affiliation(s)
- J Ma
- Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, PR China
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20
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Liu BF, Xie QG, Lu YT. Identifying the orientation of DNA fragment in recombinant plasmid by capillary electrophoresis with a non-gel sieving solution. ANAL SCI 2001; 17:1253-6. [PMID: 11759504 DOI: 10.2116/analsci.17.1253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
It was demonstrated that a capillary electrophoresis (CE) method with a non-gel sieving solution has been developed to identify the orientation of DNA fragments in recombinant plasmids in molecular biology. The influences of the concentration of sieving polymer HEC, the applied electric field strength and sampling on CE separation were analyzed concerning the optimization of separation. YO-PRO-1 was used as a DNA intercalating reagent to facilitate fluorescence detection. Under the chosen conditions (buffer, 1 x TBE containing 1 microM YO-PRO-1 and 1.2% HEC; applied electric field strength, 200 V/cm; electrokinetic sampling: time, 5 s; voltage, -6 kV), three DNA markers (phi 174/HaeIII, pBR322/HaeIII and lambda DNA/HindIII) were tested for further evaluating the relationship between the DNA size and the mobility. The established CE method conjugated with the enzymatic approach was successfully applied to identifying the DNA orientation of recombinant plasmid in transgene operations of a newly cloned gene from Arabidopsis Thaliana.
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Affiliation(s)
- B F Liu
- Key Laboratory of MOE for Plant Developmental Biology, Wuhan University, Wuhan, 430072, P.R. China
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Abstract
Capillary zone electrophoresis (CZE) with a non-gel-sieving system was employed to characterize actinomycin D-induced cell apoptosis by measuring cellular DNA damage, termed DNA ladder, which proved to be thoroughly different from the DNA damage pattern of cell necrosis. The results by CZE analyses were identical to those obtained by conventional slab gel electrophoresis, demonstrating that CZE would be a reliable and more convenient technique for the identification of cell death with advantages of higher performance, high-speed, minute sample requirement, and advanced automation.
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Affiliation(s)
- B F Liu
- Key Lab of MOE for Plant Developmental Biology, Wuhan University, Wuhan, 430072 People's Republic of China
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Abstract
It was demonstrated that a separation of 20 amino acids constituting a protein and three phosphoamino acids that mostly frequently occur in eukaryotes was achieved within 15 min by capillary electrophoresis coupled with lamp-induced fluorescence detection. Fluorescein isothiocyanate was employed as the fluorescence label to facilitate the fluorescence detection of the 23 amino acid species. The fluorescent derivatization conditions and separation parameters including concentration of electrolyte, surfactant in buffer, applied voltage and sample injection were investigated in detail and optimized. The influence of buffer additives such as methanol, acetone and polyvinylpyrrolidone on separation selectivity and sensitivity were discussed. We showed that addition of 2% polyvinylpyrrolidone into the running buffer could dramatically enhance the separation selectivity of amino acids at the expense of a decrease of sensitivity of phosphoamino acids. Under the optimized conditions, the detection limits (S/N=2) ranged from 1.90 x 10(-8) M to 5.66 x 10(-8) M with an average efficiency of 620,000/m. The method was applied to characterization of the phosphorylation of a novel protein kinase RCaMBP (calcium/calmodulin-binding protein kinase) encoded by a cDNA newly isolated and cloned from rice. We verified that RCaMBP belonged to a type of Ser/Thr kinase, providing insight into its function in signal transduction.
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Affiliation(s)
- B F Liu
- Key Laboratory of MOE for Plant Developmental Biology, Wuhan University, China
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Liu BF, Liu LB, Chen H, Cheng JK. Separation of vanadium, niobium and tantalum as ternary mixed-ligand complexes by capillary electrophoresis using chelation with 4-(2-pyridylazo)resorcinol and tartaric acid. Fresenius J Anal Chem 2001; 369:195-7. [PMID: 11225366 DOI: 10.1007/s002160000604] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Vanadium(V), niobium(V) and tantalum(V) were separated as ternary mixed-ligand complexes by capillary electrophoresis using 4-(2-pyridylazo)resorcinol (PAR) as the color chelating reagent. Four carboxylic acids such as tartaric acid (Tart), oxalic acid, citric acid and acetic acid were investigated as the additional ligand. The first was chosen as the best. Other parameters such as the concentration ratio of Tart to PAR, buffer concentration, injection time and applied voltage were also optimized. Under the optimized conditions, a complete separation of the three metal complexes was accomplished within 10 min. A linear calibration curve in the range of two orders of magnitude was obtained.
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Affiliation(s)
- B F Liu
- Department of Chemistry, Wuhan University, Wuhan 430072, P. R. China
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Liu BF, Yuan W, Meyer F, Meyer-Hofmeister E, Xie GZ. Evaporation of Accretion Disks around Black Holes: The Disk-Corona Transition and the Connection to the Advection-dominated Accretion Flow. Astrophys J 1999; 527:L17-L20. [PMID: 10566989 DOI: 10.1086/312383] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We apply the disk-corona evaporation model (Meyer & Meyer-Hofmeister) originally derived for dwarf novae to black hole systems. This model describes the transition of a thin cool outer disk to a hot coronal flow. The mass accretion rate determines the location of this transition. For a number of well-studied black hole binaries, we take the mass flow rates derived from a fit of the advection-dominated accretion flow (ADAF) model to the observed spectra (for a review, see Narayan, Mahadevan, & Quataert) and determine where the transition of accretion via a cool disk to a coronal flow/ADAF would be located for these rates. We compare this with the observed location of the inner disk edge, as estimated from the maximum velocity of the Halpha emission line. We find that the transition caused by evaporation agrees with this determination in stellar disks. We also show that the ADAF and the "thin outer disk + corona" are compatible in terms of the physics in the transition region.
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Liu BF, Miyata S, Kojima H, Uriuhara A, Kusunoki H, Suzuki K, Kasuga M. Low phagocytic activity of resident peritoneal macrophages in diabetic mice: relevance to the formation of advanced glycation end products. Diabetes 1999; 48:2074-82. [PMID: 10512376 DOI: 10.2337/diabetes.48.10.2074] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Formation of advanced glycation end products (AGEs) is accelerated in diabetic subjects along with hyperglycemia. Although several lines of evidence indicate that AGEs stimulate macrophages to secrete several cytokines and growth factors, little is known about the effect of AGEs on the primary function of macrophages, such as phagocytosis. On the other hand, impairment of the phagocytic function of monocytes/macrophages is suggested to contribute to the low resistance to infection in diabetic subjects. In the present study, we examined the effect of AGEs on the phagocytic function of macrophages. Using flow cytometric analysis of mouse resident peritoneal macrophages, we showed that AGEs suppress phagocytosis of fluorescent microspheres by cultured macrophages. In addition, experiments using streptozotocin-induced diabetic mice demonstrated a significant decrease in the phagocytic activity of resident peritoneal macrophages 12 weeks after induction of diabetes compared with age-matched control mice. The phagocytic activity of peritoneal macrophages correlated inversely with AGE content in the adjacent peritoneal tissue. Furthermore, reduced phagocytic activity of macrophages was associated with a reduction in intracellular ATP content. Because phagocytosis is an important component of the defense system, suppression of such activity by AGEs may explain, at least in part, the increased susceptibility of diabetic patients to infection.
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Affiliation(s)
- B F Liu
- Second Department of Internal Medicine, Kobe University School of Medicine, Japan
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Mizuiri S, Miyata S, Sakai K, Kobayashi M, Miyagi M, Nakanishi T, Liu BF, Kojima H, Hasegawa A. Effect of intraperitoneal administration of heparin on advanced glycation end-products in CAPD. Perit Dial Int 1999; 19:361-5. [PMID: 10507818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
OBJECTIVE To evaluate the effect of intraperitoneal (IP) administration of heparin on clearance of advanced glycation end-products (AGEs) and peritoneal dialysis efficiency. DESIGN Sequential self-controlled intervention study. SETTING University hospital, Department of Nephrology. PATIENTS AND METHODS Pyrraline, urea, and creatinine levels in plasma and dialysate, along with AGE-derived fluorescence intensity (excitation, 370 nm; emission, 440 nm) in dialysate were measured 0, 30, and 60 days after IP administration of heparin in 11 patients on continuous ambulatory peritoneal dialysis (CAPD). Pyrraline levels were determined by ELISA. RESULTS Heparin induced a significant decrease in plasma pyrraline levels; the values on days 0, 30, and 60 were 162.0+/-89.8 micromol/L, 101.1+/-32.1 micromol/L (p < 0.01), and 94.0+/-19.8 micromol/L (p < 0.001), respectively. Heparin also induced a tendency of increased dialysate pyrraline levels and a significant increase in AGE-derived fluorescence intensity in the dialysate. The values for the latter on days 0, 30, and 60 were 51.0+/-9.3 AU (arbitrary units/ mg of collagen), 73.5+/-16.0 AU (p < 0.001), and 65.6+/-15.5 AU (p < 0.01), respectively. Furthermore, heparin administration resulted in a significant (p < 0.01) increase in the dialysate/plasma ratio of urea (means 0.80, 0.90, and 0.94 on days 0, 30, and 60, respectively). CONCLUSION These results suggest that a beneficial effect of IP administration of heparin is in part due to its action on AGE kinetics, supporting a potential preventive strategy for peritoneal membrane distortion in CAPD.
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Affiliation(s)
- S Mizuiri
- Department of Nephrology, Toho University School of Medicine, Tokyo, Japan
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Sun Z, Liu BF, Chen Y, Gurewich V, Zhu D, Liu JN. Analysis of the forces which stabilize the active conformation of urokinase-type plasminogen activator. Biochemistry 1998; 37:2935-40. [PMID: 9485445 DOI: 10.1021/bi971702c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
It was recently proposed that hydrophobic interactions control the active conformation of serine proteases in the trypsin family (Hedstrom et al. (1996) Biochemistry 35, 4515-23) rather than a charge interaction with Asp next to the active site Ser, as formerly believed. In the present study, certain site-directed mutants of the serine protease zymogen pro-urokinase (pro-UK) and its two-chain enzymatic derivative urokinase (UK) were characterized. The results provide information on the structure-function of the catalytic domain of pro-UK/UK, which is relevant to this controversy. Mutations at Asp355(c194), which eliminated its charge, induced a 6250-fold reduction in the catalytic activity of UK. By contrast, reducing the hydrophobicity at the neoterminal Ile159(c16) of UK had relatively little effect. However, when both the hydrophobicity and the size of the side chain were reduced by a glycine substitution at this position, a major reduction (9090-fold) in the catalytic efficiency of UK occurred. This effect was related to the smaller side chain increasing the cavity and the flexibility of the N-terminus and thereby interfering with its charge interaction with Asp355(c194). A similar mechanism, rather than a change in hydrophobicity, is believed also to explain the reduction in the stabilization energy of the activation domain observed in a trypsin mutant by Hedstrom et al. (1996). Although hydrophobic interaction facilitated the charge interaction with Asp355(c194), the latter was the primary force which stabilized the active conformation of UK. The charge interaction with Asp355(c194) was also found to be the principal determinant of the intrinsic catalytic activity of single-chain pro-UK. Additionally, the findings confirmed that the KM of pro-UK for its natural substrate was significantly lower than that of UK. Since this same phenomenon was also seen with each of the mutants, the substrate binding pocket of these single-chain zymogens was better formed than that of their two-chain, enzymatic derivatives.
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Affiliation(s)
- Z Sun
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biochemistry, Nanjing University, Nanjing, People's Republic of China
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Sun Z, Jiang Y, Ma Z, Wu H, Liu BF, Xue Y, Tang W, Chen Y, Li C, Zhu D, Gurewich V, Liu JN, Zhong M, Xu Y. Identification of a flexible loop region (297-313) of urokinase-type plasminogen activator, which helps determine its catalytic activity. J Biol Chem 1997; 272:23818-23. [PMID: 9295329 DOI: 10.1074/jbc.272.38.23818] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Pro-urokinase has a much higher intrinsic catalytic activity than other zymogens of the serine protease family. Lys300(c143) in an apparent "flexible loop" region (297-313) was previously shown to be an important determinant of this intrinsic catalytic activity. This was related to the loop allowing the positive charge of Lys300(c143) to transiently interact with Asp355(c194), thereby inducing an active conformation of the protease domain (Liu, J. N., Tang, W., Sun, Z., Kung, W., Pannell, R., Sarmientos, P., and Gurewich, V. (1996) Biochemistry 35, 14070-14076). To further test this hypothesis, the charge at position 300(c143) and the flexibility of the loop were altered using site-directed mutagenesis designed according to a computer model to affect the interaction between Lys300(c143) and Asp355(c194). When the charge at Lys300(c143) but not Lys313(c156) was reduced, a significant reduction in the intrinsic catalytic activity occurred. Similarly, when the flexibility (wobbliness) of the loop was enhanced reducing the size of side chain, the intrinsic catalytic activity was also reduced. By contrast, when the loop was made less flexible, the intrinsic catalytic activity was increased. These findings were consistent with the hypothesis. The effects of these mutations on two-chain activity were less and often discordant with the intrinsic catalytic activity, indicating that they can be modulated independently. This structure-function disparity can be exploited to create a more zymogenic pro-urokinase (lower intrinsic catalytic activity) with a high catalytic activity, as exemplified by two of the mutants. The changes in intrinsic catalytic activity and two-chain activity induced by the mutations were due to changes in kcat rather than Km. Some significant structure-function differences between pro-urokinase and its highly homologous counterpart, tissue plasminogen activator, were also found.
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Affiliation(s)
- Z Sun
- Vascular Research Laboratory, Institute for the Prevention of Cardiovascular Disease, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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Kuo TH, Liu BF, Yu Y, Wuytack F, Raeymaekers L, Tsang W. Co-ordinated regulation of the plasma membrane calcium pump and the sarco(endo)plasmic reticular calcium pump gene expression by Ca2+. Cell Calcium 1997; 21:399-408. [PMID: 9223676 DOI: 10.1016/s0143-4160(97)90051-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The plasma membrane calcium pump (PMCA) and sarco(endo)plasmic reticular calcium pump (SERCA) are important components of the Ca2+ homeostasis system responsible for intracellular Ca2+ signaling, yet the factors which govern their expression remain unclear. Recently, we have found that overexpression of PMCA by a gene transfection approach caused a down-regulation of the SERCA pump [Liu B.F., Xu X., Fridman R., Muallem S., Kuo T.H. Consequences of functional expression of the plasma membrane calcium pump isoform 1a. J Biol Chem 1996; 271: 5536-5544]. The results suggest an interdependence between PMCA and SERCA gene expression which has prompted us to investigate further on the mechanisms that regulate the expression of these Ca2+ pump genes in various cultured cell lines. In the present study, we have analyzed the isoforms of the PMCA and SERCA in different cells and presented evidence in favor of a co-induction of the PMCA and SERCA gene expression by second messengers, such as protein kinase C, cAMP, and Ca2+. Ectopic expression of PMCA or SERCA led to downregulation of the endogenous forms of both pumps. Changes in the level of mRNAs were paralleled by corresponding altered pump protein contents. The Ca(2+)-mediated increase of gene expression is accompanied by increased transcription rates as indicated by nuclear run-on assay. The co-ordinated induction of the PMCA and SERCA gene expression by thapsigargin was not blocked by the cytosolic application of the Ca2+ chelator BAPTA. We conclude that genes encoding components of the major Ca2+ transport pathways, including pumps and IP3 receptor channels, are regulatorally linked and this link is provided by the Ca2+ load of the ER store. This study points to the importance of gene expression as an integral component in the regulation of cellular Ca2+ homeostasis.
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Affiliation(s)
- T H Kuo
- Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA.
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Abstract
It has been hypothesized that advanced Maillard reaction in vivo could explain some of the age- and diabetes-related changes. Furthermore, involvement of the Maillard reaction with Alzheimer's disease has also been suggested, as advanced glycation end products, such as pyrraline and pentosidine, were demonstrated to localize in lesions of the disease. Although aminoguanidine has been studied extensively and established as an inhibitor of the Maillard reaction, other candidates have not been investigated thoroughly. In the present study, we examined the inhibitory effect of tenilsetam [(+/-)-3-(2-thienyl)-2-piperazinone], an antidementia drug, on the Maillard reaction. Tenilsetam inhibited glucose- and fructose-induced polymerization of lysozyme in a concentration-dependent manner in vitro. Reduced enzymatic digestibility of collagen incubated with 100 mM glucose for 4 weeks was also restored to a control level by coincubation with 100 mM tenilsetam. To determine whether tenilsetam inhibits the Maillard reaction in vivo, streptozotocin-induced diabetic rats were treated with tenilsetam (50 mg/kg x day). Elevated levels of advanced glycation end-product-derived fluorescence and pyrraline in renal cortex and aorta of diabetic rats were suppressed by the administration of tenilsetam for 16 weeks. These inhibitory effects of this agent on advanced glycation in diabetic rats suggested its potential therapeutic role in controlling diabetic complications.
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Affiliation(s)
- H Shoda
- Second Department of Internal Medicine, Kobe University School of Medicine, Chuo-ku, Japan
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Miyata S, Liu BF, Shoda H, Ohara T, Yamada H, Suzuki K, Kasuga M. Accumulation of pyrraline-modified albumin in phagocytes due to reduced degradation by lysosomal enzymes. J Biol Chem 1997; 272:4037-42. [PMID: 9020111 DOI: 10.1074/jbc.272.7.4037] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Previous studies suggested that the interaction between proteins modified by advanced glycation end products (AGEs) and cells, such as macrophages, may be involved in diabetic angiopathy. Pyrraline is one of the AGEs and known to be elevated in plasma of diabetic rats and humans, and is present in vascular lesions of diabetic and elderly subjects. We examined whether modification of albumin by pyrraline influences its degradation by macrophage-like cell line, P388D1 cells. Degradation of pyrraline-modified albumin by these cells was diminished, causing accumulation of the albumin in these cells. The susceptibility of pyrraline-modified albumin to lysosomal proteolytic enzymes was reduced by approximately 40% in vitro, while lysosomal activity in the cells per se was not affected. This phenomenon was also observed when human monocytes were used instead of P388D1 cells. Our results suggest that accumulation of pyrraline-modified albumin in P388D1 cells is due to the reduced susceptibility of the protein to lysosomal enzymatic degradation. Such alterations in the interaction between AGEs-modified protein and phagocytes may contribute to angiopathy in elderly subjects and patients with diabetes.
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Affiliation(s)
- S Miyata
- The Second Department of Internal Medicine, Kobe University School of Medicine, 7-5-1, Kusunoki-cho, Chuo-ku, Kobe 650, Japan
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Cheng G, Liu BF, Yu Y, Diglio C, Kuo TH. The exit from G(0) into the cell cycle requires and is controlled by sarco(endo)plasmic reticulum Ca2+ pump. Arch Biochem Biophys 1996; 329:65-72. [PMID: 8619636 DOI: 10.1006/abbi.1996.0192] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The intracellular calcium pump sarco(endo)plasmic reticulum Ca2+ (SERCA) is responsible for the formation of the Ca2+ gradient across the endoplasmic reticulum membrane, and this gradient is used to generate the Ca2- signal during agonist-stimulated cell growth. In the present study, the role of SERCA in both cell cycle and growth control was investigated using cultured rat aortic endothelial cells (RAEC). Using a novel DNA transfection approach, cell lines were established that showed varying degree of SERCA activity through the down-regulation of the endogenous SERCA gene (B. F. Liu, X. Xu, R. Fridman, S. Muallem, and T. H. Kuo, J. Biol. Chem. 271, 1--9, 1996). Cell proliferation studies indicated that the lower SERCA expressing cells exhibited a slower growth pattern without altering the doubling time which was similar for both parental and transfected RAEC lines. G1 to S phase transition was prolonged with a smaller proportion of cells entering DNA synthesis as indicated by thymidine incorporation assay. Comparison of transfected cell lines indicated a tight coupling of SERCA activity and the length of the G1 period. Down-regulation of SERCA gene expression was accompanied by increased mRNA levels of p21 (WAF1/CIP1), a universal cell cycle inhibitor. The delay in G1 to S progression also coincided with the up-regulation of p53 mRNA and underphosphorylation of the retinoblastoma protein. This study suggests that Ca2+ metabolism in the agonist mobilizable pool controls the cell cycle through the regulation of genes operating in the critical G1 to S checkpoint.
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Affiliation(s)
- G Cheng
- Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Abstract
The plasma membrane Ca2+-ATPase pump (PMCA) is an integral component of the Ca2+ signaling system which participates in signal transduction during agonist stimulated cell activation. To better understand the physiological function of the pump, isoform 1a (PMCA1a) was over-expressed in rat aortic endothelial cells using a stable transfection system under the control of a cytomegalovirus promoter. The cell lines selected after transfection with PMCA1a construct, expressed 3-4-fold increased pump protein which was mostly targeted to the plasma membrane as indicated by immunoperoxidase staining. Ca2+ uptake assays in a membrane preparation indicated a 3-4-fold increase in Ca2+ pumping activity in the transfected cells, and the expressed PMCA1a showed typical dependence on Ca2+ and calmodulin for stimulation of activity. Measurement of [Ca2+]i and [Ca2+]out showed that expression of PMCA1a had a profound effect on different aspects of the Ca2+ signal. The peak increase in [Ca2+]i evoked by ATP and/or thapsigargin was lower but the plateau phase was similar in the PMCA1a expressing cells. Accordingly, titration with ionomycin of Ca2+ content of internal stores, measurement of Ca2+ uptake into the thapsigargin- and oxalate-sensitive pool (endoplasmic reticulum) of isolated microsomes, Ca2+ uptake into streptolysin O-permeabilized cells, and analysis of SERCA mRNA and protein, showed that expression and activity of the SERCA pump was down-regulated in cells expressing PMCA1a pump. Expression of PMCA1a also down-regulated expression of the inositol 1,4,5-trisphosphate (IP3)-activated Ca2+ channel and the rate of IP3-mediated Ca2+ release in permeable cells, without affecting the affinity of the channel for IP3. On the other hand the rate of store depletion-dependent Ca2+ and Mn2+ influx (Ca2+ entry) into PMCA1a expressing cells was increased by about 2.6-fold. These changes prevented estimating the rate of pump-mediated Ca2+ efflux from changes in [Ca2+]i. Measurement of [Ca2+]out showed that the rate of Ca2+ efflux in cells expressing PMCA1a was about 1.45-fold higher than Neo controls, despite the 4-fold increase in the amount of functional pump protein. The overall study points to the flexibility, interdependence, and adaptability of the different components of the Ca2+ signaling systems to regulate the expression and activity of each component and maintain a nearly constant Ca2+ signal.
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Affiliation(s)
- B F Liu
- Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
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Abstract
The modulation of the plasma membrane calcium pump (PMCA) gene expression is not well understood. We now present evidence that PMCA mRNA is induced by various hormones or agonists via multiple second messenger pathways that include protein kinase C-, cAMP-, and Ca(2+)-dependent mechanisms. Among several types of cultured cells examined, endothelial cells from the rat aorta (RAEC) responded to phorbol ester or angiotensin II with an 8- to 20-fold increase in the PMCA messages, while endothelial cells from the brain resistant vessel (RVEC) exhibited minimal (0- to 2-fold) response to these agonists. On the other hand, under the stimulation of cAMP or thapsigargin (a calcium mobilizing agent), the pattern of response is reversed; only RVEC responded but not RAEC. The results suggest that hormone-induced PMCA gene expression is regulated via two distinct pathways; one involves protein kinase C while the other involves Ca2+ or cAMP. Since the protein kinase A inhibitor (or the calmodulin-dependent kinase inhibitor) was able to block the stimulation elicited by either Ca2+ or cAMP, we suggest that the Ca2+ and cAMP signals share a common passage leading to the induction of PMCA mRNA. The possibility of cross-talk between the distinct second messenger pathways is also discussed.
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Affiliation(s)
- T H Kuo
- Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan 48201
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35
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Abstract
A 28-yr-old man had pleural effusions coinciding with two separate episodes of acute exacerbation of chronic type B hepatitis. In both episodes, the pleural effusion was exudative with lymphocyte predominance, and there was no ascites. Hypocomplementemia was evident in the second episode when the complement level was determined, but immune complexes were not detected in the serum. The hepatitis itself was thought to be directly responsible for the pleural effusions because of meticulous exclusion of other causes and the fact that, without specific treatment, the effusions resolved completely as the hepatitis subsided.
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Affiliation(s)
- H S Lee
- Department of Internal Medicine, Graduate Institute of Clinical Medicine, National Taiwan University Hospital, Taipei
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