47 results on '"Lei, LC"'
Search Results
2. Oxidative degradation of polyvinyl alcohol by the photochemically enhanced Fenton reaction. Evidence for the formation of super-macromolecules
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Bossmann, SH, Oliveros, E., Gob, S., Kantor, M., Goppert, A., Braun, AM, Lei, LC, Yue, Po Lock, Bossmann, SH, Oliveros, E., Gob, S., Kantor, M., Goppert, A., Braun, AM, Lei, LC, and Yue, Po Lock
- Abstract
The reaction mechanism of the oxidative degradation of polyvinyl alcohol (PVA) by the photochemically enhanced Fenton reaction has been studied. Fast and efficient degradation was observed in a batch reactor, using a medium pressure mercury arc in a Pyrex envelope and employing 80\% of the stoichiometric amount of H2O2 required for the total oxidation of PVA and a concentration ratio as low as 1 mole of iron(II) sulfate per 20 moles of PVA sub-units (C2H4O). Model PVA polymers of three different molecular weights (15,000, 49,000 and 100,000 g mol(-1)) were found to follow identical degradation patterns. Strong experimental evidence supports the formation of super-macromolecules (MW: 1-5 X 10(6) g mol(-1)) consisting of oxidized PVA and trapped iron(HI) at an early reaction stage. Low molecular weight intermediates, such as oxalic acid, formic acid or formaldehyde were not found during the PVA degradation, and we may deduce that the manifold of degradation reactions is mainly taking place within the super-macromolecules from which CO2 is directly released.
- Published
- 2001
3. Homogeneous catalytic wet-air oxidation for the treatment of textile wastewater
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Lei, LC, Chen, Guohua, Hu, Xijun, Yue, Po Lock, Lei, LC, Chen, Guohua, Hu, Xijun, and Yue, Po Lock
- Abstract
An extensive series of experiments was performed to identify suitable catalysts to increase the reaction rate of wet-air oxidation of textile wastewater at relatively mild temperatures and pressures. Wastewater types treated included natural-fiber desizing wastewater, synthetic-fiber desizing wastewater, and printing and dyeing wastewater. Experimental results indicated that all catalysts tested in this investigation significantly increased the chemical oxygen demand (COD) and total organic carbon (TOC) removal rates and total COD and TOC removals. Of all catalysts tested, copper salts were the most effective. Anions in the salt solutions played a role in the catalytic process. Nitrate ions were more effective than sulfate ions. Similarly, copper nitrates were more effective than copper sulfates. A mixture of salts containing different metals performed better than any single salt.
- Published
- 2000
4. Wet air oxidation of desizing wastewater from the textile industry
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Lei, LC, Hu, XJ, Chen, GH, Porter, JF, Yue, PL, Lei, LC, Hu, XJ, Chen, GH, Porter, JF, and Yue, PL
- Abstract
Wet air oxidation (WAO) was applied to treat the desizing wastewater from natural and manmade fiber processing in a 2-L autoclave reactor. The range of operating temperatures examined was between 150 and 290 degrees C. The partial pressure of oxygen ranged from 0.375 to 2.25 MPa at a reference temperature of 25 degrees C. Variations in chemical oxygen demand (COD) and total organic carbon were monitored during each experiment and used to evaluate the performance of the reaction process. Experimental results showed that WAO is an efficient method for the treatment of desizing wastewater. A higher COD removal was achieved under gentler reaction conditions with the aid of a catalyst. A two-parameter mathematical model involving a fast reaction and a slow reaction was used to describe the WAO reaction kinetics and to calculate the reaction activation energies.
- Published
- 2000
5. Treatment of desizing wastewater containing poly(vinyl alcohol) by wet air oxidation
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Chen, Guohua, Lei, LC, Yue, Po Lock, Cen, PL, Chen, Guohua, Lei, LC, Yue, Po Lock, and Cen, PL
- Abstract
The effectiveness of wet air oxidation (WAO) is studied in a 2-L autoclave for the treatment of desizing wastewater from man-made fiber textile plants. At an oxygen pressure of less than 2 MPa, over 30-min, chemical oxygen demand (COD) removal was found to increase from 15 to 65\% when the temperature was raised from 150 to 250 degrees C. The biodegradability of the wastewater was also simultaneously increased. Up to 90\% of the COD could be removed within 120 min. A simplified reaction mechanism is proposed which involves a direct mineralization step in parallel with a step in which an intermediate is formed prior to mineralization. A kinetic model for COD removal was developed based on this reaction mechanism. The model was tested with experimental COD results over the temperature range of the experiments. The dependence of the specific reaction rate constants was found to follow the Arrhenius type of equation. The direct oxidation of poly(vinyl alcohol) (PVA) to carbon dioxide and water is the dominant reaction step. The intermediates formed are not likely to be the acetic acid but may be short segments of PVA that are easily oxidized.
- Published
- 2000
6. Copper activated carbon as catalyst for organic wastewater treatment
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Hu, Xijun, Lei, LC, Chu, HP, Yue, Po Lock, Hu, Xijun, Lei, LC, Chu, HP, and Yue, Po Lock
- Abstract
A new heterogeneous copper catalyst was developed using highly porous activated carbon as the catalyst support. The catalyst was designed to promote the oxidation of organic pollutants in dyeing and printing wastewater from the textile industry, which was carried out in a 2 1 high-pressure reactor. The new catalyst enhanced the conversion of organic compounds in dyeing and printing wastewater, shortened the reaction time, and lowered the reaction temperature and the system total pressure. The conditions for preparing the catalyst were experimentally optimized according to their catalytic oxidation efficiency in wastewater treatment. (C) 1999 Elsevier Science Ltd. All rights reserved.
- Published
- 1999
7. RA-IR studies on the structure of mercapto-ended azobenzene derivatives in self-assembled monolayers
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Li, Hy, Lei, Lc, Zhang, Hl, Zhang, J., and Zhongfan Liu
8. An artificial intelligence algorithm for the detection of pulmonary ground-glass nodules on spectral detector CT: performance on virtual monochromatic images.
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Ma ZY, Zhang HL, Lv FJ, Zhao W, Han D, Lei LC, Song Q, Jing WW, Duan H, and Kang SL
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- Humans, Male, Female, Middle Aged, Aged, Artificial Intelligence, ROC Curve, Neural Networks, Computer, Multiple Pulmonary Nodules diagnostic imaging, Radiographic Image Interpretation, Computer-Assisted methods, Adenocarcinoma in Situ diagnostic imaging, Adenocarcinoma in Situ pathology, Adenocarcinoma diagnostic imaging, Retrospective Studies, Adult, Lung Neoplasms diagnostic imaging, Tomography, X-Ray Computed methods, Algorithms
- Abstract
Background: This study aims to assess the performance of an established an AI algorithm trained on conventional polychromatic computed tomography (CT) images (CPIs) to detect pulmonary ground-glass nodules (GGNs) on virtual monochromatic images (VMIs), and to screen the optimal virtual monochromatic energy for the clinical evaluation of GGNs., Methods: Non-enhanced chest SDCT images of patients with pulmonary GGNs in our clinic from January 2022 to December 2022 were continuously collected: adenocarcinoma in situ (AIS, n = 40); minimally invasive adenocarcinoma (MIA, n = 44) and invasive adenocarcinoma (IAC, n = 46). A commercial CAD system based on deep convolutional neural networks (DL-CAD) was used to process the CPIs, 40, 50, 60, 70, and 80 keV monochromatic images of 130 spectral CT images. AI-based histogram parameters by logistic regression analysis. The diagnostic performance was evaluated by the receiver operating characteristic (ROC) curves, and Delong's test was used to compare the CPIs group with the VMIs group., Results: When distinguishing IAC from MIA, the diagnostic efficiency of total mass was obtained at 80 keV, which was superior to those of other energy levels (P < 0.05). And Delong's test indicated that the differences between the area-under-the-curve (AUC) values of the CPIs group and the VMIs group were not statistically significant (P > 0.05)., Conclusion: The AI algorithm trained on CPIs showed consistent diagnostic performance on VMIs. When pulmonary GGNs are encountered in clinical practice, 80 keV could be the optimal virtual monochromatic energy for the identification of preoperative IAC on a non-enhanced chest CT., (© 2024. The Author(s).)
- Published
- 2024
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9. Antimicrobial peptide MPX attenuates LPS-induced inflammatory response and blood-testis barrier dysfunction in Sertoli cells.
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Zhu CL, Wang L, Zhao XQ, Yang R, Zhang BY, Zhao YY, Xia XJ, Zhang HH, Chen SJ, Jiang JQ, Hu JH, Zhang GP, Bai YY, Lei LC, and Zhang XM
- Subjects
- Animals, Antimicrobial Peptides, Blood-Testis Barrier metabolism, Cattle, Interleukin-6 metabolism, Lipopolysaccharides toxicity, Male, Mice, Sertoli Cells metabolism, Testis, Tumor Necrosis Factor-alpha metabolism, Cattle Diseases metabolism, Orchitis drug therapy, Orchitis metabolism, Orchitis veterinary
- Abstract
Orchitis accounts for a high proportion of male animal reproductive disorders. Hence, it is urgent to identify drugs for the prevention and treatment of orchitis. Antimicrobial peptides (AMPs) are currently recognized as one of the most promising alternatives to antibiotics. However, the protective effects of AMPs on lipopolysaccharide (LPS)-induced orchitis have not been reported. In this study, we developed an LPS-induced orchitis model in which primary bovine Sertoli cells were used as model cells. MPX was indicated to effectively reduce the inflammatory response of Sertoli cells. MPX attenuated the gene expression of the proinflammatory cytokines TNF-α, IL-6 and IL-1β by suppressing the MAPK pathway, especially the phosphorylation of p38 and ERK. MPX also decreased the oxidative stress response caused by LPS and upregulated Occludin and Claudin-1 expression, thereby maintaining the integrity of the blood-testis barrier. Moreover, we found that MPX inhibited apoptosis in Sertoli cells. In a mouse model, we found that MPX significantly inhibited the disruptive effects of LPS, reducing seminiferous epithelium damage, vacuolations, hyperplasia, and apoptosis in spermatogenic cells and rescuing spermatogenesis. In addition, the expression of inflammatory factors such as IL-1β, IL-18, IL-6 and TNF-α was decreased after MPX treatment in the mouse testes. MPX had no effect on other organs in mice, indicating its safety. This study was undertaken to investigate how MPX regulates the inflammatory response in Sertoli cells and provide a reference for the clinical prevention and treatment of male animal orchitis., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2022
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10. Development and Validation of a Random Forest Risk Prediction Pneumothorax Model in Percutaneous Transthoracic Needle Biopsy.
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Wu HL, Yan GW, Lei LC, Du Y, Niu XK, and Peng T
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- Adult, Age Factors, Aged, Aged, 80 and over, Biopsy, Needle, Feasibility Studies, Female, Humans, Image-Guided Biopsy methods, Male, Middle Aged, Patient Acuity, Pneumothorax etiology, Reproducibility of Results, Retrospective Studies, Risk Factors, Young Adult, Pneumothorax diagnosis, Postoperative Complications diagnosis, Radiography, Interventional methods, Tomography, X-Ray Computed methods
- Abstract
BACKGROUND Computed tomography (CT)-guided percutaneous transthoracic needle biopsy (PTNB) is an effective means for diagnosing various thoracic diseases. Pneumothorax is the most common complication, and when it becomes life-threatening, urgent medical intervention is required. The purpose of this study was to develop and validate a model that can be used to predict postoperative pneumothorax following CT-guided PTNB. MATERIAL AND METHODS We enrolled 245 patients who completed CT-guided PTNB to develop the model. A random forest (RF) model was built using 15 risk factors (15-RFs). The 7 most critical risk factors (7-RFs) were extracted by feature selection and used to build a new model. The independent external validation data contained 97 patients. Logistic regression (LR), support vector machine (SVM), and decision tree (DT) models were also developed using both 15-RFs and 7-RFs, and their performance was compared with the RF models. RESULTS The length of the aerated lung traversed was identified as the most important risk factor for developing pneumothorax, followed by angle of pleural puncture, lesion depth, lesion size, age, procedure time, and sex. The RF model demonstrated better performance in the development and validation datasets when compared with the LR, SVM, and DT based on 15-RFs and 7-RFs. According to DeLong's test for difference in ROC curves, the RF models based on the 15-RFs and 7-RFs achieved similar classification performance (P>0.05). CONCLUSIONS This study demonstrated the feasibility of using the 7-RFs RF model for predicting postoperative pneumothorax before patients undergo CT-guided PTNB.
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- 2021
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11. RAD50 Loss of Function Variants in the Zinc Hook Domain Associated with Higher Risk of Familial Esophageal Squamous Cell Carcinoma.
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Ko JMY, Lam SY, Ning L, Chai AWY, Lei LC, Choi SSA, Wong CWY, and Lung ML
- Abstract
Unbiased whole-exome sequencing approaches in familial esophageal squamous cell carcinoma (ESCC) initially prioritized RAD50 as a candidate cancer predisposition gene. The combined study with 3289 Henan individuals from Northern China identified two pathogenic RAD50 protein truncation variants, p.Q672X and a recurrent p.K722fs variant at the zinc hook domain significantly conferring increased familial ESCC risk. Effects of ~10-fold higher familial ESCC risk were observed, when compared to East Asians from the gnomAD database. Functional characterization suggested that the RAD50
Q672X mutation contributes a dominant-negative effect in DNA repair of double-stranded breaks. Overexpression of the RAD50Q672X and RAD50L1264F missense mutation also sensitized cell death upon replication stress stimuli induced by formaldehyde treatment and the CHK1 inhibitor, AZD7762. Our study suggested the novel insight of the potential for synthetic lethal therapeutic options for RAD50Q672X and the East-Asian-specific RAD50L1264F variants and CHK1 inhibitors. Our study also suggested the association of RAD50 LOF variants in the zinc hook domain with a higher risk of familial ESCC in Chinese.- Published
- 2021
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12. Schizandrin B attenuates hypoxia/reoxygenation injury in H9c2 cells by activating the AMPK/Nrf2 signaling pathway.
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Zhao B, Li GP, Peng JJ, Ren LH, Lei LC, Ye HM, Wang ZY, and Zhao S
- Abstract
Schizandrin B exhibits prominent antioxidant and anti-inflammatory effects, and plays an important role in ameliorating myocardial ischemia/reperfusion injury. However, the underlying protective mechanisms remain to be elucidated. The aim of the present study was to explore the cardioprotective effects of schizandrin B against hypoxia/reoxygenation (H/R)-induced H9c2 cell injury, focusing on the role of the adenosine monophosphate-activated protein kinase (AMPK)/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in this process. The results showed that schizandrin B attenuated the H/R-induced decrease in cell viability and the increase in lactate dehydrogenase release, as well as the apoptosis rate in H9c2 cells. Schizandrin B also mitigated H/R-induced oxidative stress, as illustrated by the decrease in intracellular reactive oxygen species generation, malondialdehyde content and NADPH oxidase 2 expression, and the increase in antioxidant enzyme superoxide dismutase and glutathione peroxidase activities. In addition, schizandrin B reversed the H/R-induced upregulation of pro-inflammatory cytokines [interleukin (IL)-1β (IL-1β) tumor necrosis factor-α, IL-6 and IL-8] and the downregulation of anti-inflammatory cytokines (transforming growth factor-β and IL-10) in the culture supernatant. Notably, schizandrin B increased the expression of Nrf2, NAD(P)H: Quinone oxidoreductase (NQO-1) and heme oxygenase-1 (HO-1) in H/R-treated H9c2 cells, activating the Nrf2 signaling pathway. The cardioprotection of schizandrin B against H/R injury was inhibited by Nrf2 knockdown induced byNrf-2-specific small interfering RNA (siRNA; si-Nrf2) transfection. Furthermore, schizandrin B enhanced phosphorylated (p)-AMPK expression, while AMPK knockdown induced by AMPK-specific siRNA(si-AMPK) transfection remarkably eliminated schizandrin B-induced cardioprotection and reduced Nrf2 expression in H/R-treated H9c2 cells. Taken together, these results suggested that schizandrin B exerts cardioprotection on H/R injury in H9c2 cells due to its antioxidant and anti-inflammatory activities via activation of the AMPK/Nrf2 pathway., (Copyright: © Zhao et al.)
- Published
- 2021
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13. Pitavastatin Combined with Ezetimibe Treatment was an Effective Approach to Non-IRA Lesion of ST-segment Elevation Myocardial Infarction Patients with Primary Percutaneous Coronary Intervention.
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Zhao B, Li GP, Peng JJ, Ren LH, Lei LC, Ye HM, Wang ZY, and Zhao S
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- Aged, Cholesterol blood, Combined Modality Therapy, Critical Care, Female, Follow-Up Studies, Humans, Lipoproteins, LDL blood, Male, Middle Aged, Risk Factors, ST Elevation Myocardial Infarction drug therapy, ST Elevation Myocardial Infarction surgery, Treatment Outcome, Anticholesteremic Agents therapeutic use, Ezetimibe therapeutic use, Hydroxymethylglutaryl-CoA Reductase Inhibitors therapeutic use, Percutaneous Coronary Intervention methods, Quinolines therapeutic use, ST Elevation Myocardial Infarction therapy
- Abstract
Objective: ST-Segment Elevation Myocardial Infarction (STEMI) patients with the multivessel disease have distinctive plaque characteristics in non-IRA lesions. Intensive statin therapy was a potential approach to treat STEMI patients with the non-IRA disease. However, there is still poor evidence about the therapeutic effect. In this study, we have evaluated the detailed therapeutic effect of statin plus ezetimibe intensive therapy., Methods: For STEMI patients with non-IRA disease undergoing primary Percutaneous Coronary Intervention (PCI), 183 control STEMI patients without non-IRA disease undergoing primary PCI, and 200 STEMI patients with non-IRA disease undergoing primary PCI were introduced into this study. 200 STEMI patients with non-IRA disease undergoing primary PCI were divided into Normal group, Intensive group, Normal & Combined group, and Intensive & Combined group. The baseline information for each participant was recorded. Meanwhile, the physiological and biochemical indicators of each member with different treatments were collected after one-year follow-up., Results: For STEMI patients with non-IRA disease undergoing primary PCI, no differences could be detected in multiple indexes such as OCT examination results, age, stroke, etc. However, diabetes mellitus, smoking, and coronary Gensini score were different between different groups (P<0.05). After one year follow-up, cholesterol, low-density lipoprotein, coronary Gensini score, thin-cap fibroatheroma, length of non-infarcted arterial lesions, non-infarct artery lesion range, myocardial infarction again, and revascularization again were significantly different between different groups (P<0.05)., Conclusion: The results mentioned above suggested that pitavastatin combined with ezetimibe was an effective approach for STEMI patients with non-IRA disease undergoing primary PCI. The results obtained in this study have provided a novel method for the treatment of STEMI patients with non-IRA disease undergoing primary PCI., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
- Published
- 2021
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14. Clinical Outcome-Related Mutational Signatures Identified by Integrative Genomic Analysis in Nasopharyngeal Carcinoma.
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Dai W, Chung DL, Chow LK, Yu VZ, Lei LC, Leong MM, Chan CK, Ko JM, and Lung ML
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- Female, Follow-Up Studies, Gene Expression Profiling, Humans, Male, Middle Aged, Nasopharyngeal Carcinoma genetics, Nasopharyngeal Carcinoma pathology, Nasopharyngeal Neoplasms genetics, Nasopharyngeal Neoplasms pathology, Prognosis, Retrospective Studies, Survival Rate, Biomarkers, Tumor genetics, Gene Expression Regulation, Neoplastic, Genomics methods, Mutation, Nasopharyngeal Carcinoma mortality, Nasopharyngeal Neoplasms mortality
- Abstract
Purpose: Investigation of biological mechanisms underlying genetic alterations in cancer can assist the understanding of etiology and identify the potential prognostic biomarkers., Experimental Design: We performed an integrative genomic analysis for a total of 731 nasopharyngeal carcinoma cases from five independent nasopharyngeal carcinoma cohorts to identify the genetic events associated with clinical outcomes., Results: In addition to the known mutational signatures associated with aging, APOBEC and mismatch repair (MMR), a new signature for homologous recombination deficiency (BRCAness) was discovered in 64 of 216 (29.6%) cases in the discovery set including three cohorts. This signature appeared more frequently in the recurrent and metastatic tumors and significantly correlated with shorter overall survival (OS) in the primary tumors. Independent prognostic value of MMR and BRCAness signatures was revealed by multivariable Cox analysis after adjustment for clinical parameters and stratification by studies. The cases with both signatures had much worse clinical outcome than those without these signatures [hazard ratio (HR), 12.4; P = 0.002]. This correlation was confirmed in the validation set (HR, 8.9; P = 0.003). The BRCAness signature is highly associated with BRCA2 pathogenic germline or somatic alterations (7.8% vs. 0%; P = 0.002). Targeted sequencing results from a prospective nasopharyngeal carcinoma cohort ( N = 402) showed that the cases carrying BRCA2 germline rare variants are more likely to have poor OS and progression-free survival., Conclusions: Our study highlights importance of defects of DNA repair machinery in nasopharyngeal carcinoma pathogenesis and their prognostic values for clinical implications. These signatures will be useful for patient stratification to evaluate conventional and new treatment for precision medicine in nasopharyngeal carcinoma., (©2020 American Association for Cancer Research.)
- Published
- 2020
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15. FANCD2 Confers a Malignant Phenotype in Esophageal Squamous Cell Carcinoma by Regulating Cell Cycle Progression.
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Lei LC, Yu VZ, Ko JMY, Ning L, and Lung ML
- Abstract
Fanconi anemia patients with germline genetic defects in FANCD2 are highly susceptible to cancers. Esophageal squamous cell carcinoma (ESCC) is a deadly cancer. Little is known about the function of FANCD2 in ESCC. For detailed molecular and mechanistic insights on the functional role of FANCD2 in ESCC, in vivo and in vitro assays and RNA sequencing approaches were used. Utilizing Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) technology, FANCD2 knockout models were established to examine the functional impact in mouse models for tumor growth and metastasis and in vitro assays for cell growth, cell cycle, and cellular localization. Our RNA sequence analyses were integrated with public datasets. FANCD2 confers a malignant phenotype in ESCC. FANCD2 is significantly upregulated in ESCC tumors, as compared to normal counterparts. Depletion of FANCD2 protein expression significantly suppresses the cancer cell proliferation and tumor colony formation and metastasis potential, as well as cell cycle progression, by involving cyclin-CDK and ATR/ATM signaling. FANCD2 translocates from the nucleus to the cytoplasm during cell cycle progression. We provide evidence of a novel role of FANCD2 in ESCC tumor progression and its potential usefulness as a biomarker for ESCC disease management.
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- 2020
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16. Clinical utility of serial analysis of circulating tumour cells for detection of minimal residual disease of metastatic nasopharyngeal carcinoma.
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Ko JM, Vardhanabhuti V, Ng WT, Lam KO, Ngan RK, Kwong DL, Lee VH, Lui YH, Yau CC, Kwan CK, Li WS, Yau S, Guo C, Choi SSA, Lei LC, Chan KC, Lam CC, Chan CK, Dai W, Khong PL, and Lung ML
- Subjects
- Adolescent, Adult, Aged, Female, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Nasopharyngeal Carcinoma diagnostic imaging, Nasopharyngeal Carcinoma genetics, Nasopharyngeal Carcinoma pathology, Neoplasm Metastasis, Neoplasm, Residual genetics, Neoplasm, Residual pathology, Neoplastic Cells, Circulating pathology, Positron Emission Tomography Computed Tomography, Progression-Free Survival, Young Adult, Biomarkers, Tumor blood, Nasopharyngeal Carcinoma blood, Neoplasm, Residual blood, Neoplastic Cells, Circulating metabolism
- Abstract
Background: Nasopharyngeal carcinoma (NPC) is an important cancer in Hong Kong. We aim to utilise liquid biopsies for serial monitoring of disseminated NPC in patients to compare with PET-CT imaging in detection of minimal residual disease., Method: Prospective serial monitoring of liquid biopsies was performed for 21 metastatic patients. Circulating tumour cell (CTC) enrichment and characterisation was performed using a sized-based microfluidics CTC chip, enumerating by immunofluorescence staining, and using target-capture sequencing to determine blood mutation load. PET-CT scans were used to monitor NPC patients throughout their treatment according to EORTC guidelines., Results: The longitudinal molecular analysis of CTCs by enumeration or NGS mutational profiling findings provide supplementary information to the plasma EBV assay for disease progression for good responders. Strikingly, post-treatment CTC findings detected positive findings in 75% (6/8) of metastatic NPC patients showing complete response by imaging, thereby demonstrating more sensitive CTC detection of minimal residual disease. Positive baseline, post-treatment CTC, and longitudinal change of CTCs significantly associated with poorer progression-free survival by the Kaplan-Meier analysis., Conclusions: We show the potential usefulness of application of serial analysis in metastatic NPC of liquid biopsy CTCs, as a novel more sensitive biomarker for minimal residual disease, when compared with imaging.
- Published
- 2020
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17. BRCA2 loss-of-function germline mutations are associated with esophageal squamous cell carcinoma risk in Chinese.
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Ko JM, Ning L, Zhao XK, Chai AWY, Lei LC, Choi SSA, Tao L, Law S, Kwong A, Lee NP, Chan KT, Lo A, Song X, Chen PN, Chang YL, Wang LD, and Lung ML
- Subjects
- Adult, Aged, Asian People genetics, China, Cohort Studies, Exome, Female, Genetic Predisposition to Disease, Humans, Loss of Heterozygosity, Male, Middle Aged, Mutation, Missense, Pedigree, Penetrance, BRCA2 Protein genetics, Esophageal Neoplasms genetics, Esophageal Squamous Cell Carcinoma genetics, Genes, BRCA2, Germ-Line Mutation
- Abstract
Esophageal squamous cell carcinoma (ESCC) occurs with highest frequency in China with over 90% mortality, highlighting the need for early detection and improved treatment strategies. We aimed to identify ESCC cancer predisposition gene(s). Our study included 4,517 individuals. The discovery phase using whole-exome sequencing (WES) included 186 familial ESCC patients from high-risk China. Targeted gene sequencing validation of 598 genes included 3,289 Henan and 1,228 moderate-risk Hong Kong Chinese. A WES approach identified BRCA2 loss-of-function (LOF) mutations in 3.23% (6/186) familial ESCC patients compared to 0.21% (9/4300) in the ExAC East Asians (odds ratio [OR] = 15.89, p = 2.48 × 10
-10 ). BRCA2 LOF mutation frequency in the combined Henan cohort has significantly higher prevalence (OR = 10.55, p = 0.0035). Results were independently validated in an ESCC Hong Kong cohort (OR = 10.64, p = 0.022). One Hong Kong pedigree was identified to carry a BRCA2 LOF mutation. BRCA2 inactivation in ESCC was via germline LOF mutations and wild-type somatic allelic loss via loss of heterozygosity. Gene-based association analysis, including LOF mutations and rare deleterious missense variants defined with combined annotation dependent depletion score ≥30, confirmed the genetic predisposition role of BRCA2 (OR = 9.50, p = 3.44 × 10-5 ), and provided new evidence for potential association of ESCC risk with DNA repair genes (POLQ and MSH2), inflammation (TTC39B) and angiogenesis (KDR). Our findings are the first to provide compelling evidence of the role of BRCA2 in ESCC genetic susceptibility in Chinese, suggesting defective homologous recombination is an underlying cause in ESCC pathogenesis, which is amenable to therapeutic options based on synthetic lethality approaches such as targeting BRCA2 with PARP1 inhibitors in ESCC., (© 2019 UICC.)- Published
- 2020
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18. Establishment and comparison of Actinobacillus pleuropneumoniae experimental infection model in mice and piglets.
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Bao CT, Xiao JM, Liu BJ, Liu JF, Zhu RN, Jiang P, Li L, Langford PR, and Lei LC
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- Animals, Bacterial Load, Body Weight, Bronchoalveolar Lavage Fluid, Cytokines blood, Female, Lung microbiology, Lung pathology, Lung Injury microbiology, Lung Injury pathology, Lymphocytes, Mice, Neutrophils, Serogroup, Survival Rate, Swine, Swine Diseases microbiology, Actinobacillus Infections blood, Actinobacillus Infections immunology, Actinobacillus Infections microbiology, Actinobacillus Infections pathology, Actinobacillus pleuropneumoniae pathogenicity, Disease Models, Animal, Pleuropneumonia blood, Pleuropneumonia immunology, Pleuropneumonia microbiology, Pleuropneumonia pathology
- Abstract
Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia, a disease responsible for substantial losses in the worldwide pig industry. In this study, outbred Kunming (KM) and Institute of Cancer Research (ICR) mice were evaluated as alternative mice models for APP research. After intranasal infection of serotype 5 reference strain L20, there was less lung damage and a lower clinical sign score in ICR compared to KM mice. However, ICR mice showed more obvious changes in body weight loss, the amount of immune cells (such as neutrophils and lymphocytes) and cytokines (such as IL-6, IL-1β and TNF-α) in blood and bronchoalveolar lavage fluid (BALF). The immunological changes observed in ICR mice closely mimicked those found in piglets infected with L20. While both ICR and KM mice are susceptible to APP and induce pathological lesions, we suggest that ICR and KM mice are more suitable for immunological and pathogenesis studies, respectively. The research lays the theoretical basis for determine that mice could replace pigs as the APP infection model and it is of significance for the study of APP infection in the laboratory., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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19. Interferon-γ regulates cell malignant growth via the c-Abl/HDAC2 signaling pathway in mammary epithelial cells.
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Ren WB, Xia XJ, Huang J, Guo WF, Che YY, Huang TH, and Lei LC
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- Animals, Carcinogenesis drug effects, Carcinogenesis metabolism, Carcinogenesis pathology, Cattle, Cell Cycle Proteins metabolism, Cell Proliferation drug effects, Cell Transformation, Neoplastic drug effects, Cell Transformation, Neoplastic metabolism, Cell Transformation, Neoplastic pathology, Cells, Cultured, Epithelial Cells drug effects, Epithelial Cells metabolism, Epithelial Cells pathology, Female, Histone Deacetylase 2 antagonists & inhibitors, Histone Deacetylase 2 genetics, Imatinib Mesylate pharmacology, Interferon-gamma pharmacology, Mammary Glands, Animal drug effects, Mammary Neoplasms, Experimental etiology, Mammary Neoplasms, Experimental metabolism, Mammary Neoplasms, Experimental pathology, Proto-Oncogene Proteins c-abl antagonists & inhibitors, Signal Transduction, Valproic Acid pharmacology, Histone Deacetylase 2 metabolism, Interferon-gamma metabolism, Mammary Glands, Animal metabolism, Mammary Glands, Animal pathology, Proto-Oncogene Proteins c-abl metabolism
- Abstract
Interferon-γ (IFN-γ) has been used to control cancers in clinical treatment. However, an increasing number of reports have suggested that in some cases effectiveness declines after a long treatment period, the reason being unclear. We have reported previously that long-term IFN-γ treatment induces malignant transformation of healthy lactating bovine mammary epithelial cells (BMECs) in vitro. In this study, we investigated the mechanisms underlying the malignant proliferation of BMECs under IFN-γ treatment. The primary BMECs used in this study were stimulated by IFN-γ (10 ng/mL) for a long term to promote malignancy. We observed that IFN-γ could promote malignant cell proliferation, increase the expression of cyclin D1/cyclin-dependent kinase 4 (CDK4), decrease the expression of p21, and upregulate the expression of cellular-abelsongene (c-Abl) and histone deacetylase 2 (HDAC2). The HDAC2 inhibitor, valproate (VPA) and the c-Abl inhibitor, imatinib, lowered the expression level of cyclin D1/CDK4, and increased the expression level of p21, leading to an inhibitory effect on IFN-γ-induced malignant cell growth. When c-Abl was downregulated, the HDAC2 level was also decreased by promoted proteasome degradation. These data suggest that IFN-γ promotes the growth of malignant BMECs through the c-Abl/HDAC2 signaling pathway. Our findings suggest that long-term application of IFN-γ may be closely associated with the promotion of cell growth and even the carcinogenesis of breast cancer.
- Published
- 2019
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20. [mRNA genomics change and significance of important ion channel proteins in patients with atrial fibrillation].
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Wang RP, Wang S, Chen D, Yang N, Lei LC, Wang ZY, Ye HM, Ren LH, and Yang SX
- Subjects
- Catheter Ablation, Genomics, Heart Atria, Humans, Intermediate-Conductance Calcium-Activated Potassium Channels, Ion Channels, RNA, Messenger, Atrial Fibrillation
- Abstract
Objective: To investigate the mRNA genomics changes and significance of important ion channel proteins in patients with atrial fibrillation (AF), to reveal the mechanism of electrical remodeling in AF. Methods: Ninety patients with AF were chosen to receive the radiofrequency ablation (AF-RFA), 90 healthy subjects were included as the normal control group.The coronary sinus blood and peripheral venous blood were taken from each AF patient during the operation of AF-RFA.The genome-wide mRNA expression profile was analyzed with mRNA microarray chip, and the mRNA expression difference results for the major ion channel gene was further validated using Real-time PCR test. Results: The expression of twelve ion channel protein mRNA increased ≥2.0-fold, expression of 10 mRNA decreased ≥2.0-fold, among which K(+) channel gene KCNE4, KCND2, KCNN4 declined obviously, KCNA5 dropped 11.54-fold ( P < 0.01); KCNS3, KCNS1, KCNG1, KCNG7 and Ca(+ +) channel gene CACNA2D3 increased significantly.Compared with autologous peripheral blood, 12 mRNAs of ion channel protein in coronary sinus blood of AF patients was differentially expressed ≥2.0-fold.Compared with control group in peripheral blood, 7 ion channel protein mRNA expression differences was ≥2.0-fold, and the KCNA5 gene expression was down by 8.13-fold.RT-PCR confirmed that the trend and extent of differential expression were consistent with the chip results.The results of myocardial tissue RT-PCR showed that CACNA1C, KCNC3, KCNG1 and KCNK7 mRNA were up-regulated in AF ( P <0.05), and other ion channel mRNA expressions were down-regulated ( P <0.05). KCNA5 was down-regulated most obvious. Conclusion: The down-regulation of KCNA5 gene expression in AF patients is most obvious, and more potassium ion channel expression differences are also significant, so that the potassium ion channel reconstruction may play a dominant or much more important role in AF electrical remodeling.
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- 2018
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21. A corn straw-based diet increases release of inflammatory cytokines in peripheral blood mononuclear cells of dairy cows.
- Author
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Che YY, Xia XJ, He BP, Gao YY, Ren WB, Liu HT, Liu JF, Huang TH, Han WY, and Lei LC
- Subjects
- Animals, Diet, Female, Gene Ontology, Milk chemistry, Transforming Growth Factor beta physiology, Cattle immunology, Cytokines physiology, Leukocytes, Mononuclear immunology, Zea mays
- Abstract
Recent studies have shown that diet can affect the body's immunity. Roughage of dairy cows consists of a variety of plant materials which make different contributions to health. This study investigated the effect of different roughages on the immunity of dairy cows. Serum, peripheral blood mononuclear cells (PBMCs), and milk samples were collected from 20 multiparous mid-lactation cows fed mixed forage (MF)- or corn straw (CS)-based diets. Expression profile analysis was used to detect the differentially expressed genes (DEGs) from PBMCs. The results showed that milk protein in the MF group increased to 3.22 g/100 ml, while that of the CS group milk was 2.96 g/100 ml; by RNA sequencing, it was found that 1615 genes were differentially expressed between the CS group and the MF group among the 24 027 analyzed probes. Gene ontology (GO) and pathway analysis of DEGs suggested that these genes (especially genes coding cytokines, chemokine and its receptors) are involved in the immune response. Results were confirmed at the protein level via detecting the levels of interleukin-2 (IL-2), IL-6, IL-10, IL-12, leptin (LEP), interferon-γ (IFN-γ), transforming growth factor-β1 (TGF-β1), and tumor necrosis factor-α (TNF-α) in peripheral blood by enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay analysis. Our data supported the conclusions that the protein content in milk of the MF group was higher than that of the CS group, the CS-based diets induced more release of cytokines than the MF-based diets in dairy cows' PBMCs, and milk protein content may be affected by cytokines.
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- 2018
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22. MicroRNA-146a Deficiency Protects against Listeria monocytogenes Infection by Modulating the Gut Microbiota.
- Author
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Du CT, Gao W, Ma K, Yu SX, Li N, Yan SQ, Zhou FH, Liu ZZ, Chen W, Lei LC, Yang YJ, and Han WY
- Subjects
- Animals, Bacteria genetics, Bacteria isolation & purification, Gastrointestinal Microbiome, High-Throughput Nucleotide Sequencing, Listeriosis genetics, Mice, Mutation, Phylogeny, RAW 264.7 Cells, RNA, Bacterial genetics, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Bacteria classification, Disease Resistance, Listeria monocytogenes pathogenicity, Listeriosis prevention & control, MicroRNAs genetics
- Abstract
The gut microbiota and microRNAs play important roles in the defense against infection. However, the role of miR-146a in L. monocytogenes infection and gut microbiota remains unclear. We tried to determine whether miR-146a controlled L. monocytogenes infection by regulating the gut microbiota. Wild-type and miR-146a-deficient mice or macrophages were used to characterize the impact of miR-146a on animal survival, cell death, bacterial clearance, and gut microbiota following L. monocytogenes challenge. We found that L. monocytogenes infection induced miR-146a expression both in vitro and in vivo. When compared to wild-type mice, miR-146a-deficient mice were more resistant to L. monocytogenes infection. MiR-146a deficiency in macrophages resulted in reduced invasion and intracellular survival of L. monocytogenes . High-throughput sequencing of 16S rRNA revealed that the gut microbiota composition differed between miR-146a-deficient and wild-type mice. Relative to wild-type mice, miR-146a-deficient mice had decreased levels of the Proteobacteria phylum, Prevotellaceae family, and Parasutterella genus, and significantly increased short-chain fatty acid producing bacteria, including the genera Alistipes , Blautia , Coprococcus_1, and Ruminococcus_1 . Wild-type mice co-housed with miR-146a-deficient mice had increased resistance to L. monocytogenes , indicating that miR-146a deficiency guides the gut microbiota to alleviate infection. Together, these results suggest that miR-146a deficiency protects against L. monocytogenes infection by regulating the gut microbiota., Competing Interests: The authors declare no conflict of interest.
- Published
- 2018
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23. An anti-Propionibacterium acnes antibody shows heterologous resistance to an Actinobacillus pleuropneumoniae infection independent of neutrophils in mice.
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Liu JF, Ma QY, Zhu RN, Cheng MJ, Bao CT, Gu JM, Sun CJ, Langford PR, Han WY, and Lei LC
- Subjects
- Animals, Cyclophosphamide administration & dosage, Female, Immunity, Heterologous, Immunity, Humoral, Immunization, Passive, Leukapheresis, Mice, Mice, Inbred BALB C, Swine, Actinobacillus Infections immunology, Actinobacillus pleuropneumoniae immunology, Antibodies, Bacterial metabolism, Lung pathology, Neutrophils immunology, Pleuropneumonia, Contagious immunology, Propionibacterium acnes physiology
- Abstract
Porcine contagious pleuropneumonia is a highly fatal respiratory disease that is caused by Actinobacillus pleuropneumoniae (APP) and results in tremendous economic losses for the pig breeding industry worldwide. Previous studies have demonstrated that Propionibacterium acnes (PA) could effectively prevent APP infection in mice and pigs. The humoral immune response played a primary role during this process and anti-PA antibody could mediate macrophages to kill the bacteria. However, the role of neutrophils in this process is currently unknown. In this study, mice were injected with cyclophosphamide to deplete neutrophils and then passively immunized with anti-PA serum or negative serum. Mice were subsequently challenged with APP serotype 1. The results showed that the mice exhibited less bacterial colonization, less lung damage, and a high survival rate, which were immunized with the anti-PA antibody whether neutrophils were depleted or not. Worse still, the presence of neutrophils increased the damage to the mice after challenge. These results suggest that the activity of the anti-PA antibody against APP infection was independent of neutrophils. These findings have important significance for understanding the mechanisms of humoral immunity conferred by heterologous immunization and lay a good foundation for preventing APP infection.
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- 2017
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24. Biological characteristics of staphylococcal enterotoxin Q and its potential risk for food poisoning.
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Hu DL, Ono HK, Isayama S, Okada R, Okamura M, Lei LC, Liu ZS, Zhang XC, Liu MY, Cui JC, and Nakane A
- Subjects
- Animals, Emetics pharmacology, Enterotoxins metabolism, Enterotoxins poisoning, Enzyme-Linked Immunosorbent Assay, Humans, Interleukin-2 metabolism, Mice, Pepsin A chemistry, Risk Assessment, Shrews, Staphylococcus aureus isolation & purification, Staphylococcus aureus metabolism, Superantigens metabolism, Temperature, Trypsin metabolism, Enterotoxins chemistry, Foodborne Diseases microbiology, Staphylococcal Food Poisoning
- Abstract
Aims: To elucidate the biological characteristics and stability of a newly identified staphylococcal enterotoxin Q (SEQ) against heating and digestive enzymes and to evaluate the risk of seq-harbouring Staphylococcus aureus in food poisoning., Methods and Results: Purified SEQ was treated with heating, pepsin and trypsin which are related to food cooking, stomach and intestine conditions, respectively. Superantigenic activity of SEQ was assessed by determining the ability of IL-2 induction in mouse spleen cells. The emetic activity of SEQ was assessed using house musk shrew, a small emetic animal model. The results revealed that SEQ exhibits a remarkable resistance to heat treatment and pepsin digestion and has significant superantigenic and emetic activities. Furthermore, a sandwich ELISA for detection of SEQ production was developed, and the results showed that seq-harboring S. aureus isolates produce a large amount of SEQ., Conclusions: The newly identified SEQ had remarkable stability to heat treatment and digestive enzyme degradation and exhibited significant superantigenic and emetic activities. In addition, seq-harbouring S. aureus isolated from food poisoning outbreaks produced a large amount of SEQ, suggesting that seq-harbouring S. aureus could potentially be a hazard for food safety., Significance and Impact of the Study: This study found, for the first time, that SEQ, a nonclassical SE, had remarkable stability to heat treatment and enzyme degradation and exhibited significant emetic activity, indicating that SEQ is a high-risk toxin in food poisoning., (© 2017 The Society for Applied Microbiology.)
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- 2017
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25. Diet-driven interferon-γ enhances malignant transformation of primary bovine mammary epithelial cells through nutrient sensor GCN2-activated autophagy.
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Xia XJ, Che YY, Zhang J, Gao YY, Ao CJ, Yang HJ, Liu JX, Liu GW, Han WY, Wang YP, Wang JQ, and Lei LC
- Subjects
- Animals, Cattle, Cell Transformation, Neoplastic pathology, Cells, Cultured, Epithelial Cells pathology, Autophagy, Cell Transformation, Neoplastic metabolism, Diet, Epithelial Cells metabolism, Interferon-gamma metabolism, Neoplasm Proteins metabolism, Protein Serine-Threonine Kinases metabolism
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- 2016
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26. Autophagy mediated by arginine depletion activation of the nutrient sensor GCN2 contributes to interferon-γ-induced malignant transformation of primary bovine mammary epithelial cells.
- Author
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Xia XJ, Gao YY, Zhang J, Wang L, Zhao S, Che YY, Ao CJ, Yang HJ, Wang JQ, and Lei LC
- Abstract
Autophagy has been linked to the regulation of both the prevention and progression of cancer. IFN-γ has been shown to induce autophagy in multiple cell lines in vitro. However, whether IFN-γ can induce autophagy and whether autophagy promotes malignant transformation in healthy lactating bovine mammary epithelial cells (BMECs) remain unclear. Here, we provide the first evidence of the correlation between IFN-γ treatment, autophagy and malignant transformation and of the mechanism underlying IFN-γ-induced autophagy and subsequent malignant transformation in primary BMECs. IFN-γ levels were significantly increased in cattle that received normal long-term dietary corn straw (CS) roughage supplementation. In addition, an increase in autophagy was clearly observed in the BMECs from the mammary tissue of cows expressing high levels of IFN-γ. In vitro, autophagy was clearly induced in primary BMECs by IFN-γ within 24 h. This induced autophagy could subsequently promote dramatic primary BMEC transformation. Furthermore, we found that IFN-γ promoted arginine depletion, activated the general control nonderepressible-2 kinase (GCN2) signalling pathway and resulted in an increase in autophagic flux and the amount of autophagy in BMECs. Overall, our findings are the first to demonstrate that arginine depletion and kinase GCN2 expression mediate IFN-γ-induced autophagy that may promote malignant progression and that immunometabolism, autophagy and cancer are strongly correlated. These results suggest new directions and paths for preventing and treating breast cancer in relation to diet.
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- 2016
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27. BHBA suppresses LPS-induced inflammation in BV-2 cells by inhibiting NF-κB activation.
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Fu SP, Li SN, Wang JF, Li Y, Xie SS, Xue WJ, Liu HM, Huang BX, Lv QK, Lei LC, Liu GW, Wang W, and Liu JX
- Subjects
- Animals, Cell Line, I-kappa B Proteins metabolism, Mice, NF-KappaB Inhibitor alpha, NF-kappa B, Signal Transduction drug effects, 3-Hydroxybutyric Acid pharmacology, Inflammation chemically induced, Inflammation metabolism, Lipopolysaccharides pharmacology
- Abstract
β-Hydroxybutyric acid (BHBA) has neuroprotective effects, but the underlying molecular mechanisms are unclear. Microglial activation plays an important role in neurodegenerative diseases by producing several proinflammatory enzymes and proinflammatory cytokines. The current study investigates the potential mechanisms whereby BHBA affects the expression of potentially proinflammatory proteins by cultured murine microglial BV-2 cells stimulated with lipopolysaccharide (LPS). The results showed that BHBA significantly reduced LPS-induced protein and mRNA expression levels of iNOS, COX-2, TNF-α, IL-1β, and IL-6. Blocking of GPR109A by PTX resulted in a loss of this anti-inflammatory effect in BV-2 cells. Western blot analysis showed that BHBA reduced LPS-induced degradation of IκB-α and translocation of NF-κB, while no effect was observed on MAPKs phosphorylation. All results imply that BHBA significantly reduces levels of proinflammatory enzymes and proinflammatory cytokines by inhibition of the NF-κB signaling pathway but not MAPKs pathways, and GPR109A is essential to this function. Overall, these data suggest that BHBA has a potential as neuroprotective drug candidate in neurodegenerative diseases.
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- 2014
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28. Expression of recombinant human lysozyme-tachyplesin I (hLYZ-TP I) in Pichia pastoris and analysis of antibacterial activity.
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Gao Y, Zhao HL, Feng X, Zhai RD, Zhu S, DU CT, Sun CJ, and Lei LC
- Subjects
- Antimicrobial Cationic Peptides genetics, DNA-Binding Proteins genetics, Humans, Microbial Sensitivity Tests, Muramidase genetics, Peptides, Cyclic genetics, Pichia metabolism, Recombinant Proteins biosynthesis, Recombinant Proteins genetics, Recombinant Proteins isolation & purification, Antimicrobial Cationic Peptides biosynthesis, DNA-Binding Proteins biosynthesis, Muramidase biosynthesis, Peptides, Cyclic biosynthesis
- Published
- 2013
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29. [Prognostic significance of admission N-terminal pro-brain natriuretic peptide in predicting angiographic no-reflow phenomenon during percutaneous coronary intervention in patients with acute myocardial infarction].
- Author
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Wang ZY, Liu N, Lei LC, Ren LH, Ye HM, and Peng JJ
- Subjects
- Aged, Biomarkers, Female, Humans, Male, Middle Aged, Myocardial Infarction therapy, Percutaneous Coronary Intervention, Prognosis, Treatment Outcome, Myocardial Infarction blood, Natriuretic Peptide, Brain blood, No-Reflow Phenomenon diagnosis
- Abstract
Objective: To determine the relationship between N-terminal pro-brain-type natriuretic peptide (NT-proBNP) and angiographic no-reflow phenomenon in patients with acute myocardial infarction (AMI) after primary percutaneous coronary intervention (PCI)., Methods: The data of 106 consecutive AMI patients undergoing primary PCl were collected and analyzed retrospectively. NT-proBNP was obtained pre-PCI at admission. According to the NT-proBNP level, they were divided into normal and elevated NT-proBNP groups. The no-reflow phenomenon was defined as an angiographic outcome of Thrombolysis In Myocardial Infarction (TIMI) grade < 3 without accompanying mechanical factors., Results: The patients with elevated NT-proBNP on admission had a higher incidence of no-reflow phenomenon than those with NT-proBNP level. Compared to normal reflow counterparts, no-reflow patients had a higher NT-proBNP level [1883 ng/L (484 ∼ 5500 ng/L) vs 220 ng/L (87 ∼ 926 ng/L) P = 0.046]. Multivariate analysis showed that a high NT-proBNP level (NT-proBNP > 1765 ng/L) on admission was an independent predictor of no-reflow. This cut-off value yielded a sensitivity of 60.0% and a specificity of 87.5% respectively., Conclusion: The NT-proBNP level on admission may be a prognostic biomarker in the prediction of the development of angiographic "no-reflow" phenomenon after primary PCI for AMI patients.
- Published
- 2012
30. [Emergent retention of organic liquid by modified bentonites: property and mechanism].
- Author
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Li Y, Liu XJ, Zhang XW, and Lei LC
- Subjects
- Adsorption, Benzene chemistry, Benzene isolation & purification, Cetrimonium Compounds chemistry, Chlorobenzenes chemistry, Chlorobenzenes isolation & purification, Computer Simulation, Environmental Pollution prevention & control, Nitrobenzenes chemistry, Nitrobenzenes isolation & purification, Organic Chemicals chemistry, Pilot Projects, Bentonite chemistry, Organic Chemicals isolation & purification, Quaternary Ammonium Compounds chemistry
- Abstract
In this study, the property and mechanism of modified bentonites synthesized by long chain quaternary ammonium compounds which would be used in the emergent retention of typical organic liquid (benzene, chlorobenzene, nitrobenzene and diesel) were investigated and a pilot-scale simulation experiment was conducted. The unit retention capacity of modified bentonites for organic liquid (2.83-9.01 g x g(-1)) was much higher than that of conventional retention agents (0.28-1.17 g x g(-1)). The property and amount of the surfactants used and viscosity of organic liquid had a significant influence on the retention capacity of modified bentonites for the organic liquid, for example, the bentonites modified by cetyltrimethylammonium (CTMAB) with an adding quantity of 100% CEC showed the highest efficiency in the retention of organic liquid. In the simulation experiment, organic liquid could be retained effectively within 30 min by emergent retention device with modified bentonites and the retention efficiency might reach positively up to 90%. Results indicated that modifications using surfactants could enhance the hydrophobicity and interlayer space of the modified bentonites and make their retention capacities for organic liquid improved.
- Published
- 2012
31. [The effect of the metallic dental materials on magnetic resonance imaging].
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Liu GS, Ren QY, Meng LQ, Lei LC, and Wang Y
- Subjects
- Diffusion Magnetic Resonance Imaging, Humans, Dental Materials, Magnetic Resonance Imaging
- Abstract
Objective: To explore the influence of conventional metal materials in oral cavity on brain magnetic resonance imaging (MRI)., Methods: Four kinds of metal materials (metal ligature wire, forging hard and slotless denture, casting nichrome denture, casting copper alloy denture) in oral cavity were scanned through MRI. FSE sequence T1 weighted imaging (FSE T1), EPI diffusion-weighted imaging (DWI) sequence of ordinary, Propeller DWI imaging were used., Results: In FSE T1 sequence, metal ligature wire and forging hard and slotless denture produced serious false image, casting nichrome denture produced moderate false image, casting copper alloy denture produced only little false image. In EPI DWI sequence, obvious magnetic-sensitive false image were produced in the dissection tissue of the brain by metal ligature wire. While in Propeller DWI sequence, magnetic-sensitive false image were greatly reduced and satisfactory images were formed., Conclusion: Different metal materials in oral cavity have different influence on the MRI. The false images produced by different metal materials are closely related to the type of the material. Magnetic-sensitive false images can be eliminated by Propeller DWI technique.
- Published
- 2010
32. Identification and characterization of Th cell epitopes in MrkD adhesin of Klebsiella pneumoniae.
- Author
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Li Y, Li ZJ, Han WY, Lei LC, Sun CJ, Feng X, Du CT, Du TF, and Gu JM
- Subjects
- Adhesins, Bacterial genetics, Algorithms, Amino Acid Sequence, Animals, Cells, Cultured, Epitope Mapping, Female, Fimbriae Proteins genetics, Humans, Klebsiella Infections microbiology, Klebsiella pneumoniae chemistry, Klebsiella pneumoniae genetics, Mice, Mice, Inbred BALB C, Molecular Sequence Data, Adhesins, Bacterial chemistry, Adhesins, Bacterial immunology, Fimbriae Proteins chemistry, Fimbriae Proteins immunology, Klebsiella Infections immunology, Klebsiella pneumoniae immunology, T-Lymphocytes, Helper-Inducer immunology
- Abstract
In this study, we identified the Th epitopes in MrkD of Klebsiella pneumoniae, an excellent vaccine candidate antigen. By using the RANKPEP prediction algorithm, we have identified and characterized three Th epitopes within the MrkD antigen, which can be recognized by CD4+ T cells from BALB/c (H-2(d)) mice. They were M(221-235), M(175-189), and M(264-278). These epitopes have important value for studying the immune response of K. pneumoniae infection and for designing effective vaccine against K. pneumoniae., (Copyright 2010 Elsevier Ltd. All rights reserved.)
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- 2010
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33. [Effect of tirofiban in acute anterior myocardial infarction patients without ST segment resolution after primary percutaneous coronary intervention].
- Author
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Peng JJ, Ma ZM, Ren LH, Ma ZM, Ren LH, Fu GQ, Jia KY, Lei LC, and Ye HM
- Subjects
- Aged, Angioplasty, Balloon, Coronary, Anterior Wall Myocardial Infarction therapy, Electrocardiography, Female, Humans, Male, Middle Aged, Prognosis, Tirofiban, Treatment Outcome, Tyrosine therapeutic use, Anterior Wall Myocardial Infarction diagnosis, Anterior Wall Myocardial Infarction drug therapy, Platelet Aggregation Inhibitors therapeutic use, Tyrosine analogs & derivatives
- Abstract
Objective: To observe the effect of glycoprotein receptor blockade tirofiban in acute anterior myocardial infarction patients without ST segment resolution after primary percutaneous coronary intervention (PCI)., Methods: From April 2006 to April 2008, 157 acute anterior myocardial infarction patients without ST segment resolution after PCI were randomly allocated to tirofiban (intravenous bolus 10 microg/kg followed by intravenous infusion of 0.15 microgxkg(-1)xmin(-1) for 48 h, n = 80) or equal volume saline (control group, n = 77). Baseline characteristics, PCI features and clinical outcomes during hospitalization, left ventricular ejection fractions (LVEF) and major adverse cardiac events (MACE, including death, re-infarction and target vessel revascularization) at 30 and 180 days after discharge were compared between the two groups., Results: The baseline clinical characteristics were comparable between the two groups. Compared to control group, the MACE rates and re-infarction rates at 30 days (6.3% vs.18.2%, P < 0.05; 1.3% vs.9.1%, P < 0.05, respectively) and 180 days (10.0% vs.23.4%, P < 0.05; 2.5% vs.10.4%, P < 0.05, respectively) were significantly reduced in tirofiban group. LVEF value was significantly higher in tirofiban group at 30 days and 180 days compared with those in control group [(51 +/- 6)% vs. (46 +/- 8)%, P < 0.05; (57 +/- 7)% vs. (50 +/- 9)%, P < 0.05]. Hemorrhagic complications were similar between the two groups., Conclusion: Use of tirofiban for acute anterior myocardial infarction patients without ST segment resolution after PCI is safe and can significantly improve 30 and 180 days clinical outcomes after discharge.
- Published
- 2009
34. [Clinical outcomes of trimetazidine in patients with acute ST segment elevation myocardial infarction without ST segment resolution after primary percutaneous coronary intervention].
- Author
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Peng JJ, Ma ZM, Ren WL, Ren LH, Lei LC, and Liang Y
- Subjects
- Aged, Angioplasty, Balloon, Coronary, Electrocardiography, Humans, Middle Aged, Myocardial Infarction diagnosis, Prospective Studies, Treatment Outcome, Myocardial Infarction drug therapy, Myocardial Infarction physiopathology, Trimetazidine therapeutic use, Vasodilator Agents therapeutic use
- Abstract
Objective: To evaluate prospectively the clinical outcomes of trimetazidine (TMZ) in patients with acute ST segment elevation myocardial infarction (STEMI) without ST segment resolution (STR) after primary percutaneous coronary intervention (PPCI)., Methods: From August 2005 to October 2007, 138 acute STEMI patients without STR after PPCI were randomly assigned to either with TMZ therapy (TMZ group, n = 70) or without TMZ (control group, n = 68). Baseline characteristics, PCI features and clinical outcomes during hospitalization were compared between the two groups. Left ventricular ejection fraction (LVEF) and major adverse cardiac events (MACE, including death, re-infarction and target vessel revascularization) at Days 30 and 180 after discharge were also compared., Results: The baseline clinical characteristics were comparable between the two groups. There was no significant difference in MACE rates at Days 30 and 180 between the two groups (10/70 vs 11/68, P > 0.05; 15/70 vs 13/68, P > 0.05, respectively). The LVEFs of TMZ group at Days 30 and 180 were significantly superior to the control group (51 +/- 8)% vs (45 +/- 7)%, P < 0.05; (56 +/- 7)% vs (49 +/- 8)%, P < 0.05, respectively)., Conclusion: Use of TMZ for patients with acute STEMI without STR after primary PCI can improve the left ventricular function at Days 30 and 180.
- Published
- 2009
35. Klebsiella pneumoniae MrkD adhesin-mediated immunity to respiratory infection and mapping the antigenic epitope by phage display library.
- Author
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Li Y, Han WY, Li ZJ, and Lei LC
- Subjects
- Animals, Antibodies, Bacterial immunology, Antibodies, Monoclonal immunology, Female, Mice, Mice, Inbred BALB C, Peptide Library, Adhesins, Bacterial immunology, Antigens, Bacterial immunology, Epitope Mapping, Fimbriae Proteins immunology, Klebsiella pneumoniae immunology, Pneumonia, Bacterial immunology, Pneumonia, Bacterial prevention & control
- Abstract
In this study, the K. pneumoniae MrkD adhesin was identified an immunodominant antigen which correlated with protection against infection by K. pneumoniae. The mouse monoclonal antibodies (mAbs) against MrkD adhesin were produced by the hybridoma technique using recombinant MrkD-GST as the immunogen and were immunoscreened against phage-displayed random dodecapeptide library (Ph.D.-12). After three rounds of biopanning, 36 phage clones were randomly selected and their specificity to mAb was verified by sandwich and competitive inhibition ELISA. Sixteen phage clones were sequenced and their amino acids were deduced. One mimotope (QKTLAKSTYMSA) showed good match with MrkD adhesion at 148-159 aa and the serum of mice induced by the phage clone clearly recognized MrkD adhesion.
- Published
- 2009
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36. [Activities of circulating endothelial progenitor cells in patients with in-stent restenosis].
- Author
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Lei LC, Huo Y, Li JP, Li XX, Han YY, Wang HZ, and Zhu Y
- Subjects
- Angioplasty, Balloon, Coronary, Antigens, CD34 analysis, Cell Adhesion, Cell Count, Cell Movement, Cell Proliferation, Coronary Restenosis pathology, Endothelial Cells metabolism, Humans, Microscopy, Fluorescence, Stem Cells metabolism, Stents, Vascular Endothelial Growth Factor A analysis, Coronary Restenosis blood, Endothelial Cells cytology, Stem Cells cytology
- Abstract
Objective: To observe the number and activities of circulating endothelial progenitor cells (EPCs) in patients with in-stent restenosis., Methods: Peripheral blood samples were collected from 15 patients with angiographically restenosis, and 17 baseline characteristics-matched patients without angiographically restenosis (control group). Mononuclear cells were isolated by Ficoll density-gradient centrifugation and plated on dishes coated with human fibronectin. After 7 days in culture, the nature of EPCs was characterized with anti-CD34 and anti-KDR, specific surface antibodies of EPC, and confirmed further with the use of fluorescein isothiocyanate-labeled ulex europaeus agglutinin-I (FITC-UEA-I) and DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine percolate)-labeled acetylated low-density lipoprotein (DiI-acLDL) by laser scanning confocal microscopy. The number of EPCs was counted in a blinded manner. EPCs were inoculated onto the culture plate and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazolium bromide assay was used to measure the A value by enzyme labeling instrument to evaluate the proliferation. The migration of EPCs was assayed by scratch assay. EPC adhesion was performed by replating cells on fibronectin-coated dishes and then counting the adherent cells. Results The number of EPCs of the patients with in-stent restenosis was 4.97 +/- 1.42/well, significantly lower than that of the control group (17.2 +/- 3.90/well, P = 0.001). MTT assay showed that the proliferative activities of the in-stent restenosis group was 1.37 +/- 0.32 times the baseline value, significantly lower than that of the control group (2.01 +/- 0.62, P < 0.05). The number of migrating EPCs of the in-stent restenosis group was remarkably lower than that of the control group. There was no significant difference in the adherent activity between the two groups. Conclusion The number, proliferation activity, and migration activity of the EPCs patients with in-stent restenosis are all significantly lower, which may contribute to the mechanism of in-stent restenosis.
- Published
- 2007
37. [Autopsy for two cases of acute tetramine poisoning].
- Author
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Xu YC, Chen B, Chen JZ, Lei LC, and Bai YQ
- Subjects
- Acute Disease, Adult, Autopsy, Child, Humans, Male, Poisoning pathology, Bridged-Ring Compounds poisoning, Rodenticides poisoning
- Published
- 2006
38. Study on NO(2) absorption by ascorbic acid and various chemicals.
- Author
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Li W, Wu CZ, Fang HL, Shi Y, and Lei LC
- Subjects
- Absorption, Air Pollutants chemistry, Air Pollutants isolation & purification, Ascorbic Acid chemistry, Nitric Oxide chemistry, Nitric Oxide isolation & purification
- Abstract
Study on NO(2) absorption aimed at seeking a better NO(2) absorption chemical at pH 4.5 approximately 7.0 for application to existing wet flue gas desulfurization (FGD). The results from the double-stirred reactor indicated that ascorbic acid has very high absorption rate at this pH range. The rate constant of ascorbic acid reaction with NO(2) (0 approximately 1,000 x 10(-6) mol/mol) is about 3.54 x 10(6) mol/(Ls) at pH 5.4 approximately 6.5 at 55 degrees C.
- Published
- 2006
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39. Experimental study on the inhibition of biological reduction of Fe(III)EDTA in NO(x) absorption solution.
- Author
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Li W, Wu CZ, Zhang SH, Shi Y, and Lei LC
- Subjects
- Adsorption, Edetic Acid antagonists & inhibitors, Edetic Acid metabolism, Ferric Compounds antagonists & inhibitors, Klebsiella growth & development, Oxidation-Reduction, Chelating Agents metabolism, Ferric Compounds metabolism, Iron metabolism, Klebsiella metabolism, Nitrogen Oxides metabolism
- Abstract
Scrubbing of NO(x) from the gas phase with Fe(II)EDTA has been shown to be highly effective. A new biological method can be used to convert NO to N(2) and regenerate the chelating agent Fe(II)EDTA for continuous NO absorption. The core of this biological regeneration is how to effectively simultaneous reduce Fe(III)EDTA and Fe(II)EDTA-NO, two mainly products in the ferrous chelate absorption solution. The biological reduction rate of Fe(III)EDTA plays a main role for the NO(x) removal efficiency. In this paper, a bacterial strain identified as Klebsiella Trevisan sp. was used to demonstrate an inhibition of Fe(III)EDTA reduction in the presence of Fe(II)EDTA-NO. The competitive inhibition experiments indicted that Fe(II)EDTA-NO inhibited not only the growth rate of the iron-reduction bacterial strain but also the Fe(III)EDTA reduction rate. Cell growth rate and Fe(III)EDTA reduction rate decreased with increasing Fe(II)EDTA-NO concentration in the solution.
- Published
- 2005
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40. Cross-host evolution of severe acute respiratory syndrome coronavirus in palm civet and human.
- Author
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Song HD, Tu CC, Zhang GW, Wang SY, Zheng K, Lei LC, Chen QX, Gao YW, Zhou HQ, Xiang H, Zheng HJ, Chern SW, Cheng F, Pan CM, Xuan H, Chen SJ, Luo HM, Zhou DH, Liu YF, He JF, Qin PZ, Li LH, Ren YQ, Liang WJ, Yu YD, Anderson L, Wang M, Xu RH, Wu XW, Zheng HY, Chen JD, Liang G, Gao Y, Liao M, Fang L, Jiang LY, Li H, Chen F, Di B, He LJ, Lin JY, Tong S, Kong X, Du L, Hao P, Tang H, Bernini A, Yu XJ, Spiga O, Guo ZM, Pan HY, He WZ, Manuguerra JC, Fontanet A, Danchin A, Niccolai N, Li YX, Wu CI, and Zhao GP
- Subjects
- Amino Acid Substitution, Animals, China epidemiology, Disease Outbreaks, Genes, Viral, Humans, Membrane Glycoproteins genetics, Phylogeny, Polymorphism, Single Nucleotide, Severe acute respiratory syndrome-related coronavirus isolation & purification, Severe acute respiratory syndrome-related coronavirus pathogenicity, Severe acute respiratory syndrome-related coronavirus physiology, Severe Acute Respiratory Syndrome epidemiology, Severe Acute Respiratory Syndrome transmission, Species Specificity, Spike Glycoprotein, Coronavirus, Viral Envelope Proteins genetics, Zoonoses epidemiology, Zoonoses transmission, Zoonoses virology, Evolution, Molecular, Severe acute respiratory syndrome-related coronavirus genetics, Severe Acute Respiratory Syndrome virology, Viverridae virology
- Abstract
The genomic sequences of severe acute respiratory syndrome coronaviruses from human and palm civet of the 2003/2004 outbreak in the city of Guangzhou, China, were nearly identical. Phylogenetic analysis suggested an independent viral invasion from animal to human in this new episode. Combining all existing data but excluding singletons, we identified 202 single-nucleotide variations. Among them, 17 are polymorphic in palm civets only. The ratio of nonsynonymous/synonymous nucleotide substitution in palm civets collected 1 yr apart from different geographic locations is very high, suggesting a rapid evolving process of viral proteins in civet as well, much like their adaptation in the human host in the early 2002-2003 epidemic. Major genetic variations in some critical genes, particularly the Spike gene, seemed essential for the transition from animal-to-human transmission to human-to-human transmission, which eventually caused the first severe acute respiratory syndrome outbreak of 2002/2003.
- Published
- 2005
- Full Text
- View/download PDF
41. Synergetic effects for p-nitrophenol abatement using a combined activated carbon adsorption-electrooxidation process.
- Author
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Zhou MH, Dai QZ, Lei LC, and Wang DH
- Subjects
- Electrochemistry instrumentation, Equipment Design, Equipment Failure Analysis, Ultrafiltration instrumentation, Charcoal chemistry, Electrochemistry methods, Nitrophenols chemistry, Ultrafiltration methods, Water Pollutants, Chemical isolation & purification, Water Purification methods
- Abstract
A novel fluidized electrochemical reactor that integrated advanced electrochemical oxidation with activated carbon (AC) fluidization in a single cell was developed to model pollutant p-nitrophenol (PNP) abatement. AC fluidization could enhance COD removal by 22%-30%. In such a combined process, synergetic effects on PNP and COD removal was found, with their removal rate being enhanced by 137.8% and 97.8%, respectively. AC could be electrochemically regenerated and reused, indicating the combined process would be promising for treatment of biorefractory organic pollutants.
- Published
- 2004
- Full Text
- View/download PDF
42. Synthesis of TiO(2) supported on activated carbon by MOCVD: operation parameters study.
- Author
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Zhang XW, Zhou MH, Lei LC, and Xu S
- Subjects
- Adsorption, Catalysis, Combinatorial Chemistry Techniques, Gases chemistry, Molecular Conformation, Particle Size, Powders, Temperature, Titanium isolation & purification, Charcoal chemistry, Crystallization methods, Nanotubes chemistry, Nanotubes ultrastructure, Titanium chemistry
- Abstract
The metallo-organic chemical vapor deposition (MOCVD) technique has been applied to the preparation of the photocatalyst titanium dioxide supported on activated carbon. The effects of various condition parameters such as carrier gas flow rate, source temperature and deposition temperature on the deposition rate were investigated. The maximum deposition rate of 8.2 mg/(g x h) was obtained under conditions of carrier gas flow rate of 400 ml/min, source temperature of 423 K and deposition temperature of 913 K. The deposition rate followed Arrhenius behavior at temperature of 753 K to 913 K, corresponding to activation energy E(a) of 51.09 kJ/mol. TiO(2) existed only in anatase phase when the deposition temperature was 773 K to 973 K. With increase of deposition temperature from 1073 K to 1273 K, the rutile content sharply increased from 7% to 70%. It was found that a deposition temperature of 773 K and a higher source temperature of 448 K resulted in finely dispersed TiO(2) particles, which were mainly in the range of 10-20 nm.
- Published
- 2004
- Full Text
- View/download PDF
43. Heterogeneous UV/Fenton catalytic degradation of wastewater containing phenol with Fe-Cu-Mn-Y catalyst.
- Author
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Zheng ZW, Lei LC, Xu SJ, and Cen PL
- Subjects
- Computer Simulation, Hydrogen-Ion Concentration, Industrial Waste prevention & control, Kinetics, Oxidation-Reduction, Phenol isolation & purification, Ultraviolet Rays, Hydrogen Peroxide chemistry, Metals chemistry, Models, Chemical, Phenol chemistry, Phenol radiation effects, Photochemistry methods, Water Purification methods
- Abstract
The heterogeneous UV/Fenton process with the appropriate amount of Fe-Mn-Cu-Y as catalyst was developed and various operation conditions for the degradation of phenol were evaluated. The results indicated that by using the heterogeneous UV/Fenton process, the COD(cr) removal rate reached almost 100% for wastewater containing phenol. Compared with the homogeneous process, the developed catalyst could be used at wider pH range in the UV/Fenton process. Comparison of various heterogeneous process showed that heterogeneous UV/Fenton process was best. The heterogeneous UV/Fenton process with Fe-Mn-Cu-Y catalyst is highly efficient in degrading various organic pollutants.
- Published
- 2004
- Full Text
- View/download PDF
44. Degradation kinetics and mechanisms of phenol in photo-Fenton process.
- Author
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He F and Lei LC
- Subjects
- Computer Simulation, Hydrogen-Ion Concentration, Industrial Waste prevention & control, Kinetics, Oxidation-Reduction, Phenol isolation & purification, Ultraviolet Rays, Hydrogen Peroxide chemistry, Iron chemistry, Models, Chemical, Phenol chemistry, Phenol radiation effects, Photochemistry methods, Water Purification methods
- Abstract
Phenol degradation in photochemically enhanced Fenton process was investigated in this work. UV-VIS spectra of phenol degradation showed the difference between photo-Fenton process and UV/H(2)O(2), which is a typical hydroxyl radical process. A possible pathway diagram for phenol degradation in photo-Fenton process was proposed, and a mathematical model for chemical oxygen demand (COD) removal was developed. Operating parameters such as dosage of H(2)O(2) and ferrous ions, pH, suitable carrier gas were found to impact the removal of COD significantly. The results and analysis of kinetic parameters calculated from the kinetic model showed that complex degradation of phenol was the main pathway for removal of COD; while hydroxyl radicals acted weakly in the photo-Fenton degradation of phenol.
- Published
- 2004
- Full Text
- View/download PDF
45. Degradation of 4-CP in an internal electrolysis system.
- Author
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Bian WJ, Shen XY, and Lei LC
- Subjects
- Catalysis, Charcoal chemistry, Gas Chromatography-Mass Spectrometry, Iron, Kinetics, Oxygen chemistry, Waste Disposal, Fluid instrumentation, Chlorophenols chemistry, Electrolysis methods, Waste Disposal, Fluid methods
- Abstract
The characteristic and mechanism of parachlorophenol (4-CP) degradation in an internal electrolysis system were investigated. The degradation rate of 4-CP was higher in acid solution than that of in neutral or alkaline solution. Addition of activated carbon could make 4-CP easier be degraded by the surface contact catalysis. The dissolved oxygen in solution could take part in the electrode reaction and intensify the degradation of 4-CP. By the analysis of intermediates of degradation of 4-CP, it could be conferred that 4-CP was broken through the bond beside hydroxy firstly, then the bond beside chloride was broken and the chloride was dechlorinated simultaneously. Most intermediate products were glycerine, ethane diacid and acetic acid, while very few 1,4-butanedial and alcohols were found.
- Published
- 2004
46. Photochemically enhanced degradation of phenol using heterogeneous Fenton-type catalysts.
- Author
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He F, Shen XY, and Lei LC
- Subjects
- Catalysis, Environmental Pollution prevention & control, Hydrogen Peroxide chemistry, Iron chemistry, Oxidants chemistry, Oxidation-Reduction, Photochemistry, Disinfectants chemistry, Phenol chemistry
- Abstract
The degradation of phenol was carried out using heterogeneous Fenton-type catalysts in the presence of H2O2 and UV. Catalysts were prepared by exchanging and immobilizing Fe2+ in zeolite 13X, silica gel or Al2O3. The concentration of phenol solution was 100 mg/L. The amount of H2O2 added was the stoichiometric amount of H2O2 required for the total oxidation of phenol. Under the irradiation of medium pressure light (300 W) phenol was mineralized within 1 h in the presence of Fe2+/zeolite 13X. The COD removal rate was enhanced in the presence of Fe2+/zeolite 13X compared to that of Fe2+/silica gel or Fe2+/Al2O3. Analogous homogenous photo-Fenton reaction with equivalent Fe2+ was also carried out to evaluate the catalysis efficiency of Fe2+/zeolite 13X. Results showed that the COD removal rate was near to that of homogeneous Fenton, while heterogeneous Fe2+/zeolite 13X catalyst could be recycled.
- Published
- 2003
47. [Determination of esculetin in semen Euphorbiae lathyridis L. by TLCS and comparison on the quality in different areas].
- Author
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Li ZG, Sun XG, Zhou KF, Lei LC, and Zhai YJ
- Subjects
- China, Chromatography, Thin Layer, Densitometry, Species Specificity, Drugs, Chinese Herbal chemistry, Umbelliferones analysis
- Abstract
A TLC-densitometric method for the determination of oesculetin in Semen Euphorbia lathyridis (Euphorbiae lathyrdis) was established, and esculetin content in Semen Euphorbia lathyridis from three different producing areas (Zhengzhou, Chengdu and Chongqing) was determined. The method is accurate, sensitive and simple. The recovery is 98.63% and the coefficient of variation is 1.59% (n = 5). The esculetin average contents in the three samples are 0.3013%, 0.2046% and 0.2094% respectively.
- Published
- 1993
Catalog
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