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Wang R, Lin Y, Le S, Lu D, Gao L, Feng C, Wang G, Xiao P. Short- and medium-chain chlorinated paraffins in breast milk in Shanghai, China: Occurrence, characteristics, and risk assessment. Environ Pollut 2024; 347:123690. [PMID: 38452837 DOI: 10.1016/j.envpol.2024.123690] [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] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 02/28/2024] [Accepted: 02/28/2024] [Indexed: 03/09/2024]
Abstract
As novel contaminants, short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) have been of great concern in the past several years. Shanghai was one of the provinces with the largest chlorinated paraffins (CPs) emission in China; nevertheless, there is currently little information on the human exposure to SCCPs and MCCPs, particularly MCCPs. In this study, 25 breast milk samples were collected in Shanghai from 2016 to 2017. The concentrations of SCCPs and MCCPs were determined using two-dimensional gas chromatography coupled with orbitrap high-resolution mass spectrometry (GC × GC-orbitrap-HRMS) to investigate their characteristics and assess the associated health risks for breast-fed infants. Compared with the previous studies in other areas, the current study presented the higher CPs concentrations, with median concentrations of SCCPs and MCCPs up to 771 and 125 ng/g lipid weight (lw), respectively. The exposure profiles of the CPs were characterized by C10 and Cl6-7 as the predominant congeners of SCCPs, while C14 and Cl7-9 were identified as the dominant groups of MCCPs. CP-42 and CP-52 were identified as potential sources of CPs found in breast milk samples collected in Shanghai. The concentrations of MCCPs exhibited a positive correlation (p value < 0.05) with the dietary consumption of meat and poultry. No significant positive correlations were observed for SCCPs and MCCPs with polychlorinated dibenzodioxins/furans (PCDD/Fs) congeners. A preliminary exposure assessment showed that SCCPs in breast milk potentially posed high risks to the breast-fed infants in Shanghai.
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Affiliation(s)
- Runhua Wang
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
| | - Yuanjie Lin
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
| | - Sunyang Le
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
| | - Dasheng Lu
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
| | - Lirong Gao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
| | - Chao Feng
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
| | - Guoquan Wang
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
| | - Ping Xiao
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
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Feng C, Lin Y, Le S, Ji J, Chen Y, Wang G, Xiao P, Zhao Y, Lu D. Suspect, Nontarget Screening, and Toxicity Prediction of Per- and Polyfluoroalkyl Substances in the Landfill Leachate. Environ Sci Technol 2024; 58:4737-4750. [PMID: 38408453 DOI: 10.1021/acs.est.3c07533] [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] [Subscribe] [Scholar Register] [Indexed: 02/28/2024]
Abstract
Landfills are the final stage of urban wastes containing perfluoroalkyl and polyfluoroalkyl substances (PFASs). PFASs in the landfill leachate may contaminate the surrounding groundwater. As major environmental pollutants, emerging PFASs have raised global concern. Besides the widely reported legacy PFASs, the distribution and potential toxic effects of numerous emerging PFASs remain unclear, and unknown PFASs still need discovery and characterization. This study proposed a comprehensive method for PFAS screening in leachate samples using suspect and nontarget analysis. A total of 48 PFASs from 10 classes were identified; nine novel PFASs including eight chloroperfluoropolyether carboxylates (Cl-PFPECAs) and bistriflimide (HNTf2) were reported for the first time in the leachate, where Cl-PFPECA-3,1 and Cl-PFPECA-2,2 were first reported in environmental media. Optimized molecular docking models were established for prioritizing the PFASs with potential activity against peroxisome proliferator-activated receptor α and estrogen receptor α. Our results indicated that several emerging PFASs of N-methyl perfluoroalkyl sulfonamido acetic acids (N-MeFASAAs), n:3 fluorotelomer carboxylic acid (n:3 FTCA), and n:2 fluorotelomer sulfonate (n:2 FTSA) have potential health risks that cannot be ignored.
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Affiliation(s)
- Chao Feng
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Yuanjie Lin
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Sunyang Le
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Jieyun Ji
- Shanghai Changning Center for Disease Control and Prevention, Shanghai 200051, China
| | - Yuhang Chen
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Guoquan Wang
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Ping Xiao
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Yunfeng Zhao
- China National Center for Food Safety Risk Assessment, Beijing 100021, China
- NHC Key Laboratory of Food Safety Risk Assessment, Beijing 100021, China
| | - Dasheng Lu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
- State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
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Lin Y, Feng C, Le S, Qiu X, Xu Q, Jin S, Fang Y, Jin Y, Wen Y, Wang G, Lu D. Infant Exposure to PCBs and PBDEs Revealed by Hair and Human Milk Analysis: Evaluation of Hair as an Alternative Biomatrix. Environ Sci Technol 2022; 56:15912-15919. [PMID: 36301106 DOI: 10.1021/acs.est.2c04045] [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] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Human hair, as an emerging biological monitoring matrix, has begun to be used in various human exposure studies, but little research has been done on persistent organic pollutants (POPs), especially for the body burden of POPs in infants. In this study, 36 breast-fed infants in Shanghai were recruited for a study to determine their exposure to POPs, including 12 dioxin-like polychlorinated biphenyls (dl-PCBs), 6 indicator PCBs, and 8 polybrominated diphenyl ethers (PBDEs) in the inner layer (internal) and outer layer (external) of infant hair and human milk. The similarity or difference of the POP distribution pattern or concentration among these matrices was investigated, and only weak correlations (r < 0.4) were observed between the POP concentration in human milk and infant hair (internal or external). POPs in human milk have a different profile than those in infant hair, while they have stable concentration ratios (0.58-2.72), similar distribution patterns, fine Spearman's rank correlations, and tangled principal component analysis (PCA) plots in each POP family between external and internal hair samples. The result suggested that POPs in internal hair can be easily affected by those in external hair, but POPs in human milk seem to have little contribution to the POP profile in internal hair. Although infant hair cannot reflect the POPs from diet or from body burden, it can be an ideal biomatrix that estimates infant exposure to POPs from exogenous sources like house dust when considering the similar pattern of POPs and their proper accumulation period in hair.
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Affiliation(s)
- Yuanjie Lin
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Chao Feng
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Sunyang Le
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Xinlei Qiu
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Qian Xu
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Shuping Jin
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Yamin Fang
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Yu'e Jin
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Yimin Wen
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Guoquan Wang
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
| | - Dasheng Lu
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai 200336, China
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Waters M, Dobry A, Le S, Shinkai K, Maverakis E, Kaffenberger B. 333 A modified delphi consensus exercise: developing a skin-directed Stevens-Johnson Syndrome/toxic epidermal necrolysis scoring system. J Invest Dermatol 2022. [DOI: 10.1016/j.jid.2022.05.342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Liakos W, Ji-Xu A, Artounian K, Downing L, Nava J, Toussi A, Le S, Maverakis E. 378 Real-world utilization of Delphi consensus diagnostic criteria for pyoderma gangrenosum referrals. J Invest Dermatol 2022. [DOI: 10.1016/j.jid.2022.05.387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Feng C, Xu Q, Qiu X, Jin Y, Ji J, Lin Y, Le S, Xue L, Chen Y, She J, Xiao P, Lu D, Wang G. Profiling of pesticides and pesticide transformation products in Chinese herbal teas. Food Chem 2022; 383:132431. [PMID: 35180605 DOI: 10.1016/j.foodchem.2022.132431] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [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: 11/22/2021] [Revised: 01/29/2022] [Accepted: 02/08/2022] [Indexed: 11/04/2022]
Abstract
Herbal teas have potential health benefits, but they also contain a variety of pesticides and pesticide transformation products (PTPs) that might brings health risks. Our study maps the pesticides and PTPs in two herbal teas (chrysanthemum and Lusterleaf Holly) from two main producing areas in China. Almost all 122 samples contain pesticides, with concentration ranging from 0.0005 to 10.305 mg/kg. Nearly 40% carbendazim and imidacloprid in chrysanthemum teas and λ-cyhalothrin in Lusterleaf Holly have higher concentration levels than the values permitted in EC Regulation No. 396/2005. Distinct distributions of pesticides were found in different teas and production areas. Eight PTPs were identified along with their parents, and were confirmed using a biosynthetic strategy. Acute, chronic and cumulative health risk assessments of pesticides revealed acceptable results. Our study uncovers the profile of pesticides in herbal teas, and provides new insight into discovering the potential environmental pollution and food contaminants.
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Affiliation(s)
- Chao Feng
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Qian Xu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Xinlei Qiu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Yu'e Jin
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Jieyun Ji
- Shanghai Changning Center for Disease Control and Prevention, Shanghai 200051, China
| | - Yuanjie Lin
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Sunyang Le
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Liming Xue
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Yuhang Chen
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China
| | - Jianwen She
- California Department of Public Health, Richmond, CA 94804, USA
| | - Ping Xiao
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
| | - Dasheng Lu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China.
| | - Guoquan Wang
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai 200336, China.
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Le S, Zhang Y, Voutilainen A, Tan X, Laukkanen J, Wang C, Cheng S. Differences in cardiometabolic risk profiles between Chinese and Finnish older adults with glucose impairment and central obesity. J Endocrinol Invest 2022; 45:1427-1437. [PMID: 35325446 PMCID: PMC9184414 DOI: 10.1007/s40618-022-01777-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [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: 11/08/2021] [Accepted: 02/23/2022] [Indexed: 12/06/2022]
Abstract
BACKGROUND Obesity and ethnicity play important roles in cardiovascular complications in patients with type 2 diabetes mellitus (T2DM). This study aimed to compare cardiometabolic risk profiles between Chinese and Finnish older adults of central obesity with prediabetes or T2DM. METHODS Study subjects were 60-74 years old and originated from two population samples. The Finnish subjects came from the Kuopio Ischemic Heart Disease (KIHD) study (n = 1089), and the Chinese subjects came from the Shanghai High-risk Diabetic Screen (SHiDS) study (n = 818). The KIHD and SHiDS studies used similar questionnaires to determine participants' baseline characteristics regarding the history of medication use and diseases and lifestyle factors. All study subjects participated in glucose tolerance tests and anthropometry assessments, including waist circumference measurements. RESULTS Among study subjects of central obesity with prediabetes (n = 298), fasting and 2-h glucose, and fasting insulin and insulin resistance were significantly higher in Chinese than in Finnish (p < 0.0001-0.016). In addition, triglyceride (TG) level was higher and the low-density lipoprotein cholesterol (LDL) and LDL to high-density lipoprotein cholesterol (HDL) ratio were lower in Chinese than in Finnish (p < 0.0001-0.003). Among subjects of central obesity with T2DM (n = 251), Chinese subjects had significantly less proportions of antihypertensive, glycaemic control medication, and statin users as well as lower level of physical activity (p < 0.0001 for all), while higher blood pressure (p = 0.002 for systolic blood pressure and p < 0.0001 for diastolic blood pressure), TG levels (p < 0.05) and HDL (p = 0.002) than the Finnish counterparts. There were no differences in β-cell function (HOMA-β) between Chinese and Finnish both in prediabetes and T2DM. CONCLUSIONS Our results indicated that Chinese and Finnish older adults of central obesity with prediabetes and T2DM had similar β-cell function. However, Chinese individuals with prediabetes are prone to insulin resistance. Meanwhile, lipid metabolism dysfunction is also different between Chinese and Finnish. Chinese older adults of central obesity with prediabetes showed higher TG, but Finnish showed higher LDL and LDL/HDL. Strategic for T2DM prevention and treatment should be ethnically specific.
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Affiliation(s)
- S Le
- Exercise Translational Medicine Center, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, 200240, Shanghai, China
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China
- Department of Physical Therapy, Taihe Hospital, Hubei University of Medicine, Shiyan, 442099, China
- Faculty of Sport and Health Sciences, University of Jyväskylä, 40014, Jyväskylä, Finland
| | - Y Zhang
- Shanghai Jiao Tong University Affiliated Sixth People's Hospital, The Metabolic Disease Biobank, Shanghai, 200233, China
| | - A Voutilainen
- Institute of Public Health and Clinical Nutrition, University of Eastern Finland, 70211, Kuopio, Finland
| | - X Tan
- Exercise Translational Medicine Center, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, 200240, Shanghai, China
- Department of Neuroscience, Uppsala University, BMC, Box 593, 75124, Uppsala, Sweden
| | - J Laukkanen
- Faculty of Sport and Health Sciences, University of Jyväskylä, 40014, Jyväskylä, Finland.
- Institute of Public Health and Clinical Nutrition, University of Eastern Finland, 70211, Kuopio, Finland.
- Institute of Clinical Medicine, Department of Medicine, University of Eastern Finland, 70211, Kuopio, Finland.
| | - C Wang
- Department of Endocrinology and Metabolism, School of Medicine, Shanghai Fourth People's Hospital Affiliated to Tongji University, Tongji University, 1279 Sanmen Road, Shanghai, 200434, China.
| | - S Cheng
- Exercise Translational Medicine Center, Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, 200240, Shanghai, China.
- Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Center for Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, 200240, China.
- Faculty of Sport and Health Sciences, University of Jyväskylä, 40014, Jyväskylä, Finland.
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Lemoine A, Colas AS, Le S, Delacourt C, Tounian P, Lezmi G. Le syndrome d’entérocolite induite par les protéines alimentaires chez les enfants : une large cohorte multicentrique française. NUTR CLIN METAB 2022. [DOI: 10.1016/j.nupar.2021.12.126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Liakos W, Toussi A, Merleev A, Marusina A, Leal AR, Le S, Maverakis E. LB712 Transcriptomic profiling of Necrobiotic Xanthogranuloma and Necrobiosis Lipoidica provides insight into pathogenic role of T and B cells. J Invest Dermatol 2021. [DOI: 10.1016/j.jid.2021.07.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Feng C, Xu Q, Qiu X, Jin Y, Ji J, Lin Y, Le S, She J, Lu D, Wang G. Evaluation and application of machine learning-based retention time prediction for suspect screening of pesticides and pesticide transformation products in LC-HRMS. Chemosphere 2021; 271:129447. [PMID: 33476874 DOI: 10.1016/j.chemosphere.2020.129447] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 12/17/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
Computational QSAR models have gradually been preferred for retention time prediction in data mining of emerging environmental contaminants using liquid chromatography coupled with mass spectrometry. Generally, the model performance relies on the components such as machine learning algorithms, chemical features, and example data. In this study, we evaluated the performances of four algorithms on three feature sets, using 321 and 77 pesticides as the training and validation sets, respectively. The results were varied with different combinations of algorithms on distinct feature sets. Two strategies including enhancing the complexity of chemical features and enlarging the size of the training set were proved to improve the results. XGBoost, Random Forest, and lightGBM algorithms exhibited the best results when built on a large-scale chemical descriptors, while the Keras algorithm preferred fingerprints. These four models have comparable prediction accuracies that at least 90% of pesticides in validation set can be successfully predicted with ΔRT <1.0 min. Meanwhile, a blended prediction strategy using average results from four models presented a better result than any single model. This strategy was used for assisting identification of pesticides and pesticide transformation products in 120 strawberry samples from a national survey of food contamination. Twenty pesticides and twelve pesticide transformation products were tentatively identified, where all pesticides and two pesticide transformation products (bifenazate diazene and spirotetramat-enol) were confirmed by standard materials. The outcome of this study suggested that retention time prediction is a valuable approach in compound identification when integrated with in silico MS2 spectra and other MS identification strategies.
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Affiliation(s)
- Chao Feng
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China
| | - Qian Xu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China
| | - Xinlei Qiu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China
| | - Yu'e Jin
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China
| | - Jieyun Ji
- Shanghai Changning Center for Disease Control and Prevention, Shanghai, 200051, China
| | - Yuanjie Lin
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China
| | - Sunyang Le
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China
| | - Jianwen She
- California Department of Public Health, Richmond, CA, 94804, USA
| | - Dasheng Lu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
| | - Guoquan Wang
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai, 200336, China; State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, Shanghai, 200336, China.
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Ruqiao L, Yueli C, Xuelan Z, Huifen L, Xin Z, Danjie Z, Le S, Yanxue Z. Rhizoma Atractylodis macrocephalae: a review of photochemistry, pharmacokinetics and pharmacology. Pharmazie 2021; 75:42-55. [PMID: 32213234 DOI: 10.1691/ph.2020.9738] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 09/29/2022]
Abstract
Rhizoma Atractylodis macrocephalae is commonly used in Traditional Chinese Medicine. Its traditional functions include treating hypofunction of the spleen with the loss of appetite, abdominal distension diarrhea, phlegm drink dizziness palpitation, edema, fetal movement restless. A literature search was conducted by systematic searching multiple electronic databases including Web of Science, PubMed, CNKI and Google Scholar. Chemical composition analysis of RAM showed that the main compositions were volatile oil, lactones, polysaccharides, amino acids, vitamins and resins. Pharmacological studies indicated that RAM possessed antitumor activities, neuroprotective effect, anti-hepatotoxicity, immune and anti-inflammatory activity, etc. This review gives a detailed description of the chemical constituents, pharmacology and pharmacokinetics of RAM and provides reliable basis for clinical development and application.
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Affiliation(s)
- L Ruqiao
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, People's Republic of China
| | - C Yueli
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, People's Republic of China
| | - Z Xuelan
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, People's Republic of China;,
| | - L Huifen
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, People's Republic of China
| | - Z Xin
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, People's Republic of China
| | - Z Danjie
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, People's Republic of China
| | - S Le
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, People's Republic of China
| | - Z Yanxue
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan 250355, People's Republic of China
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Feng C, Xu Q, Qiu X, Jin Y, Ji J, Lin Y, Le S, Wang G, Lu D. Corrigendum to "Comprehensive strategy for analysis of pesticide multi-residues in food by GC-MS/MS and UPLC-Q-Orbitrap" [Food Chem., 320 (2020) 126576]. Food Chem 2021; 348:129153. [PMID: 33508601 DOI: 10.1016/j.foodchem.2021.129153] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Chao Feng
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
| | - Qian Xu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
| | - Xinlei Qiu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
| | - Yu'e Jin
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
| | - Jieyun Ji
- Shanghai Changning Center for Disease Control and Prevention, Shanghai 200051, China
| | - Yuanjie Lin
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
| | - Sunyang Le
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
| | - Guoquan Wang
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China
| | - Dasheng Lu
- Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200336, China.
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Lin Y, Le S, Feng C, Qiu X, Xu Q, Jin S, Zhang H, Jin Y, Wen Y, Xu H, Liu P, Rao Q, She J, Lu D. Exposure and health risk assessment of secondary contaminants closely related to brominated flame retardants (BFRs): Polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in human milk in shanghai. Environ Pollut 2021; 268:115121. [PMID: 33139099 DOI: 10.1016/j.envpol.2020.115121] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 06/18/2020] [Accepted: 06/25/2020] [Indexed: 06/11/2023]
Abstract
Polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), as the secondary environmental pollutants of the widely used brominated flame retardants (BFRs), possess the similar physicochemical and toxic properties as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). However, studies on human body exposure to them are extremely limited. In this study, forty human milk samples collected in Shanghai were measured for 13 PBDD/F congeners using gas chromatography-high resolution mass spectrometry (GC-HRMS), to investigate their exposure level and characteristics, potential source and corresponding health risks to breastfed infants. The results showed no PBDDs but three PBDF congeners including 2,3,7,8-TBDF, 1,2,3,4,6,7,8-HpBDF and OBDF (mean concentration (detection rates) are 3.2 pg/g (72.5%), 9.5 pg/g (100%) and 28 pg/g (67.5%), respectively) were detected. The average toxic equivalent quantity (TEQ, 0.42 pg/g lw) presented the highest concentration level compared to other regions reported. The contribution of PBDFs to the total TEQ of PBDD/Fs and PCDD/Fs is 6.8%. The correlation between PBDD/Fs and age or dietary habits was not observed, which normally existed in their chlorinated analogues-PCDD/Fs. Significant correlations were observed between PBDFs and highly brominated polybrominated diphenyl ethers (PBDEs) (especially for BDE 183 and BDE 209). The correlation between PCDD/Fs and PBDFs was not observed except 2,3,7,8-TBDF. The high PBDFs exposure in Shanghai may originate from the emission of PBDEs and/or non-PBDE BFRs in environment, according to the consistency of the environmental data previously reported. The average estimated dietary intakes (EDI) for breastfed infants is 2.0 pg TEQ/kg·bw/day (0.13-13 pg TEQ/kg·bw/day), within the range of the tolerable daily intake (TDI) for TCDD (1-4 pg TEQ/kg·bw/day) suggested by the World Health Organization (WHO). However, given the high toxicity of PBDD/Fs, the potential health risks of these pollutants for breastfed infants should be of concern.
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Affiliation(s)
- Yuanjie Lin
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Sunyang Le
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Chao Feng
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Xinlei Qiu
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Qian Xu
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Shuping Jin
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Huimin Zhang
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Yu'e Jin
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Yimin Wen
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China
| | - Hao Xu
- Shanghai Hongqiao Street Community Health Service Center, No.4 Lane 961 Hongqiao Road, Shanghai, 200051, China
| | - Peipei Liu
- Shanghai Jiangzhen Community Health Service Center, 762 Dongting Road, Shanghai, 201202, China
| | - Qinxiong Rao
- Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai, 201403, China
| | - Jianwen She
- Environmental Health Laboratory Branch, California Department of Public Health, Richmond, CA, United States
| | - Dasheng Lu
- Shanghai Municipal Center for Disease Control and Prevention/State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, 1380 West Zhongshan Road, Shanghai, 200336, China.
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Feng C, Xu Q, Qiu X, Jin Y, Ji J, Lin Y, Le S, Wang G, Lu D. Comprehensive strategy for analysis of pesticide multi-residues in food by GC–MS/MS and UPLC-Q-Orbitrap. Food Chem 2020; 320:126576. [DOI: 10.1016/j.foodchem.2020.126576] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 02/20/2020] [Accepted: 03/06/2020] [Indexed: 12/20/2022]
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Le S, Marusina A, Toussi A, Downing L, Tran M, Maverakis N, Luxardi G, Tsoi A, Gudjonsson J, Merleev A, Maverakis E. 035 Biogeographical differences in gene segment usage. J Invest Dermatol 2020. [DOI: 10.1016/j.jid.2020.03.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Toussi A, Merleev A, Yamada D, Shi Z, Le S, Marusina A, Luxardi G, Adamopoulos I, Hwang S, Gudjonsson J, Maverakis E. 284 Identification of psoriasis-protective chemokine, FAM19A5, and IL17D expression in psoriatic skin. J Invest Dermatol 2020. [DOI: 10.1016/j.jid.2020.03.290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Alexanian C, Merleev A, Le S, Wang J, Luxardi G, Marusina A, Wilken R, Ma C, Cheng M, Maverakis E. 359 Lipidome alterations in psoriasis and atopic dermatitis. J Invest Dermatol 2019. [DOI: 10.1016/j.jid.2019.03.435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Boulos D, Shehabi Y, Moghaddas JA, Birrell M, Choy A, Giang V, Nguyen J, Hall T, Le S. Predictive Value of Quick Sepsis-Related Organ Failure Scores following Sepsis-Related Medical Emergency Team Calls: A Retrospective Cohort Study. Anaesth Intensive Care 2017; 45:688-694. [DOI: 10.1177/0310057x1704500607] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We conducted a cohort study of adult ward patients who had a Medical Emergency Team (MET) call triggered by confirmed or suspected sepsis in an Australian tertiary centre to assess the predictive utility of systemic inflammatory response syndrome (SIRS) and quick Sepsis-Related Organ Failure Assessment (qSOFA) scores for 28-day mortality over a 12-month period. Sepsis was the causative aetiology in 970 MET calls for 646 patients with a mean age of 68 years and median Charlson Comorbidity score (CCS) of 3.0. Four hundred and seven (63%) patients had microbiological identification of a causative organism with 35 (9%) demonstrating multi–drug resistance. The 28-day mortality rate was 22%. Independent risk factors for 28-day mortality included age (incidence rate ratio [IRR] 1.038; P <0.001) and CCS (IRR 1.102; P <0.001). qSOFA positive patients had a threefold risk of 28-day mortality compared to those who were negative (IRR 3.15; P=0.02). Both the SIRS and qSOFA score had poor sensitivity (86% versus 62%, respectively) for mortality as a sole diagnostic tool and should be investigated as part of a multiparameter panel within a large prospective study.
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Affiliation(s)
- D. Boulos
- Department of General Medicine, Monash Health, Clinical Informatics, Monash Health, Melbourne, Victoria
| | - Y. Shehabi
- Critical Care Medicine, Monash Health, Melbourne, Victoria
| | - J. A. Moghaddas
- Department of General Medicine, Monash Health, Melbourne, Victoria
| | - M. Birrell
- Department of Infectious Diseases, Monash Health, Melbourne, Victoria
| | - A. Choy
- Medicine, Monash University, Melbourne, Victoria
| | - V. Giang
- Medicine, Monash University, Melbourne, Victoria
| | - J. Nguyen
- School of Clinical Sciences, Monash University, Melbourne, Victoria
| | - T. Hall
- School of Clinical Sciences, Monash University, Melbourne, Victoria
| | - S. Le
- EMR Clinical Benefits Clinician, Clinical Informatics, Monash Health, Melbourne, Victoria
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King A, Guignot N, Zerbino P, Boulard E, Desjardins K, Bordessoule M, Leclerq N, Le S, Renaud G, Cerato M, Bornert M, Lenoir N, Delzon S, Perrillat JP, Legodec Y, Itié JP. Tomography and imaging at the PSICHE beam line of the SOLEIL synchrotron. Rev Sci Instrum 2016; 87:093704. [PMID: 27782575 DOI: 10.1063/1.4961365] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
PSICHE (Pressure, Structure and Imaging by Contrast at High Energy) is the high-energy beam line of the SOLEIL synchrotron. The beam line is designed to study samples at extreme pressures, using diffraction, and to perform imaging and tomography for materials science and other diverse applications. This paper presents the tomograph and the use of the beam line for imaging, with emphasis on developments made with respect to existing instruments. Of particular note are the high load capacity rotation stage with free central aperture for installing large or complex samples and sample environments, x-ray mirror and filter optics for pink beam imaging, and multiple options for combining imaging and diffraction measurement. We describe how x-ray imaging techniques have been integrated into high-pressure experiments. The design and the specifications of the beam line are described, and several case studies drawn from the first user experiments are presented.
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Affiliation(s)
- A King
- Synchrotron SOLEIL, St-Aubin 91192, France
| | - N Guignot
- Synchrotron SOLEIL, St-Aubin 91192, France
| | - P Zerbino
- Synchrotron SOLEIL, St-Aubin 91192, France
| | - E Boulard
- Synchrotron SOLEIL, St-Aubin 91192, France
| | | | | | - N Leclerq
- Synchrotron SOLEIL, St-Aubin 91192, France
| | - S Le
- Synchrotron SOLEIL, St-Aubin 91192, France
| | - G Renaud
- Synchrotron SOLEIL, St-Aubin 91192, France
| | - M Cerato
- Synchrotron SOLEIL, St-Aubin 91192, France
| | - M Bornert
- Navier Laboratory UMR8205, Ecole des Ponts ParisTech, Paris, France
| | - N Lenoir
- PLACAMAT UMS3626, University of Bordeaux, Bordeaux, France
| | - S Delzon
- UMR Biodiversité Gènes et Communautés, INRA, Bordeaux, France
| | - J-P Perrillat
- Laboratoire de Geologie de Lyon, Terre Planetes Environnement, UMR5276-CNRS-ENSLyon-UCBLyon1, Lyon, France
| | | | - J-P Itié
- Synchrotron SOLEIL, St-Aubin 91192, France
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Dempsey B, Turner A, Le S, Allen A, Goodchild A, McMullan S. The connectome of rostral ventrolateral medulla sympathetic premotor neurons. Auton Neurosci 2015. [DOI: 10.1016/j.autneu.2015.07.401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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21
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Lopez J, Ghavami F, Nguyen V, Lee L, Le S, Jaffe R, Steinberg G, Dodd R, Marks M, Do H, Herrera G, Gonzalez-Nava N, Cho C. P154: Utility of intraoperative neurophysiologic monitoring (IONM) in altering operative management in the endovascular and surgical treatment of adult cerebral aneurysms. Clin Neurophysiol 2014. [DOI: 10.1016/s1388-2457(14)50294-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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22
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Le S, Ekwueme A, Cho S, Lee L, Nguyen V, Lopez J. P493: Retrospective waveform analysis of transcranial motor evoked potentials (MEP) to identify early predictors of impending motor deficits in spinal surgeries. Clin Neurophysiol 2014. [DOI: 10.1016/s1388-2457(14)50590-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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23
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Wipff J, Le S, Viguier F, Kahan A, Deslandre C. FRI0542 Course of Biotherapies in A Large Cohort of Juvenile Idiopathic Arthritis at Adulthood. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.5215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Nguyen V, Avila S, Cho S, Lee L, Le S, López J. P164: Intraoperative neurophysiologic monitoring of surgical and endovascular treatment of pediatric arteriovenous malformations. Clin Neurophysiol 2014. [DOI: 10.1016/s1388-2457(14)50302-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Parvizi J, Le S, Foster BL, Bourgeois B, Riviello JJ, Prenger E, Saper C, Kerrigan JF. Gelastic epilepsy and hypothalamic hamartomas: neuroanatomical analysis of brain lesions in 100 patients. Brain 2011; 134:2960-8. [DOI: 10.1093/brain/awr235] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Navada R, Kumari H, Le S, Zhang J. Oral malodor reduction from a zinc-containing toothpaste. J Clin Dent 2008; 19:69-73. [PMID: 18763690] [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] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVE To evaluate the anti-malodor efficacy of toothpaste containing 0.2% zinc sulphate after a single brushing and following extended use. METHODS Two clinical studies of common design but different malodor assessment were carried out. In the first study, volatile sulphur compounds (VSC) were measured with a Halimeter; in the second, breath freshness was assessed by odor judges (organoleptic score). At the start of the study, suitable subjects were assigned at random to either the test toothpaste (containing 0.2% zinc sulphate) or the placebo toothpaste (no zinc), and oral breath assessments were made before and two hours after brushing. The same assessments were repeated after allocated toothpastes had been used twice daily for four weeks. Prior to the before-brushing breath assessment, subjects were asked to refrain from eating/drinking and oral hygiene for 12 hours. RESULTS The results at the start and end of the study showed a significant reduction in mean Halimeter scores and a significant improvement in organoleptic scores two hours after brushing for subjects using the test toothpaste with zinc sulphate. In addition, at the end of the study, subjects using the test toothpaste with zinc sulphate had reduced Halimeter scores and improved organoleptic scores 12 hours after the last brushing compared to the placebo group. The differences between the test and placebo values ranged from 16% to 46% and were all statistically significant (p < 0.0001). CONCLUSION Both clinical studies independently support the efficacy of the test toothpaste with 0.2% zinc sulphate in reducing oral malodor after a single brushing, and after four weeks for 12 hours after brushing compared to a toothpaste without zinc ions.
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Affiliation(s)
- R Navada
- Unilever Oral Care Mumbai, India.
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Moule CA, Angelis F, Kim GH, Le S, Malipatil S, Foo MS, Burrow MF, Thomas D. Resin bonding using an all-etch or self-etch adhesive to enamel after carbamide peroxide and/or CPP-ACP treatment. Aust Dent J 2007; 52:133-7. [PMID: 17687960 DOI: 10.1111/j.1834-7819.2007.tb00478.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [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: 11/30/2022]
Abstract
BACKGROUND Limited evidence exists regarding the effect of carbamide peroxide and casein phosphopeptide amorphous calcium phosphate (CPP-ACP) on composite-enamel bonding. Microshear bond strengths, using either a total-etch or self-etching adhesive, to enamel treated with carbamide peroxide and/or CPP-ACP were investigated. MATERIALS AND METHODS Twenty-six extracted human third molars were sectioned into four parts, each being allocated into one of the four groups (n=26): bleach (Polanight, 16% carbamide peroxide), CPP-ACP (GC Tooth Mousse), bleach and then CPP-ACP, or untreated (control). The surfaces were bonded with a total-etch bonding system (Single Bond) or a self-etching primer system (Clearfil SE Bond) and tested using a microshear test. RESULTS A significant difference in bond strength was found between bonding systems. SE Bond showed the highest bond strength to untreated enamel (p < 0.05). The microshear bond strength of SE Bond decreased when the enamel was treated with carbamide peroxide, CPP-ACP or both (p < 0.05). Only combined use of carbamide peroxide and CPP-ACP significantly affected microshear bond strength with Single Bond. CONCLUSION These findings suggest the shear bond strength of resin to enamel using a self-etching priming adhesive may be affected if the enamel is treated with a bleaching agent or CPP-ACP.
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Affiliation(s)
- C A Moule
- School of Dental Science, The University of Melbourne, Victoria
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Wong SF, Ward C, Lee-Tannock A, Le S, Chan FY. Pulmonary artery/aorta ratio in simple screening for fetal outflow tract abnormalities during the second trimester. Ultrasound Obstet Gynecol 2007; 30:275-80. [PMID: 17721863 DOI: 10.1002/uog.4105] [Citation(s) in RCA: 18] [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] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
OBJECTIVES Congenital heart disease is associated with high mortality and morbidity rates, being the most life-threatening defect in the first month of postnatal life and accounting for approximately half of all childhood mortality from birth defects. Despite this, the prenatal detection rate for congenital outflow tract anomalies by ultrasound imaging is relatively low. The aim of this study was to establish a nomogram for the pulmonary artery/aorta (PA/AO) ratio measured in the three-vessel view plane. This ratio was investigated as a simple screening tool for congenital cardiac outflow tract abnormalities. METHODS The study was a prospective evaluation of 966 singleton fetuses at 16-24 weeks of gestation and 46 fetuses with congenital cardiac outflow tract abnormalities. The diameters of the pulmonary artery and aorta were measured in the three-vessel view. The PA/AO ratio was calculated and a nomogram was constructed. The mean and 95% CI for the ratio were defined and the PA/AO ratios of cases with outflow tract abnormalities were plotted against the values for normal fetuses. RESULTS The gestational age of the normal group ranged from 16 to 24 weeks, with a median of 19 weeks. The pulmonary artery diameter measured between 2.1 and 4.93 mm (mean, 3.3 mm) and the aorta measured between 2.1 and 5.2 mm (mean, 2.93 mm). The mean (SD) PA/AO ratio was 1.16 (0.18) (95% CI, 0.87-1.58; range 0.61-1.86; median, 1.14). For fetuses with outflow tract abnormalities, the median gestation was 19 weeks and 37/43 (86%) had a PA/AO ratio outside the 95% CI. CONCLUSIONS The PA/AO ratio derived from measurements in the three-vessel view plane can be used as an initial screening tool for outflow tract anomalies and may have a sensitivity of up to 86%, with a 5% false-positive rate.
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Affiliation(s)
- S F Wong
- Department of Maternal Fetal Medicine, Mater Mothers' Hospital, South Brisbane, QLD, Australia.
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Gardner J, James E, Downing D, Miller L, Shotorbani S, Le S. Acceptability of pharmacist prescribed hormonal contraceptives for healthy women in the direct access study. Contraception 2006. [DOI: 10.1016/j.contraception.2006.05.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Kakkis E, McEntee M, Vogler C, Le S, Levy B, Belichenko P, Mobley W, Dickson P, Hanson S, Passage M. Intrathecal enzyme replacement therapy reduces lysosomal storage in the brain and meninges of the canine model of MPS I. Mol Genet Metab 2004; 83:163-74. [PMID: 15464431 DOI: 10.1016/j.ymgme.2004.07.003] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.8] [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] [Received: 03/31/2004] [Revised: 07/05/2004] [Accepted: 07/07/2004] [Indexed: 11/19/2022]
Abstract
Enzyme replacement therapy (ERT) has been developed for several lysosomal storage disorders, including mucopolysaccharidosis I (MPS I), and is effective at reducing lysosomal storage in many tissues and in ameliorating clinical disease. However, intravenous ERT does not adequately treat storage disease in the central nervous system (CNS), presumably due to effects of the blood-brain barrier on enzyme distribution. To circumvent this barrier, we studied whether intrathecal (IT) recombinant human alpha-L-iduronidase (rhIDU) could penetrate and treat the brain and meninges. An initial dose-response study showed that doses of 0.46-4.14 mg of IT rhIDU successfully penetrated the brain of normal dogs and reached tissue levels 5.6 to 18.9-fold normal overall and 2.7 to 5.9-fold normal in deep brain sections lacking CSF contact. To assess the efficacy and safety in treating lysosomal storage disease, four weekly doses of approximately 1 mg of IT rhIDU were administered to MPS I-affected dogs resulting in a mean 23- and 300-fold normal levels of iduronidase in total brain and meninges, respectively. Quantitative glycosaminoglycan (GAG) analysis showed that the IT treatment reduced mean total brain GAG to normal levels and achieved a 57% reduction in meningeal GAG levels accompanied by histologic improvement in lysosomal storage in all cell types. The dogs did develop a dose-dependent immune response against the recombinant human protein and a meningeal lymphocytic/plasmacytic infiltrate. The IT route of ERT administration may be an effective way to treat the CNS disease in MPS I and could be applicable to other lysosomal storage disorders.
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Affiliation(s)
- E Kakkis
- Division of Medical Genetics, Department of Pediatrics, Harbor-UCLA Research and Education Institute, Torrance CA, USA.
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Wingerter S, Gupta S, Le S, Shamasunder S, Bernstein R, Rabitaille W, Kukuyeva Y, Downie S. Unusual origin of the flexor digiti minimi brevis muscle. Clin Anat 2003; 16:531-3. [PMID: 14566903 DOI: 10.1002/ca.10122] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [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: 11/09/2022]
Abstract
An unusual origin of the flexor digiti minimi brevis muscle of the right hand was discovered during cadaveric dissection. The muscle originated from the anterior aspect of the transverse fibers of the distal antebrachial fascia and inserted onto the base of the fifth proximal phalanx. When traction was applied to the proximal portion of the muscle, flexion was produced at the fifth metacarpophalangeal joint. Other intrinsic muscles of the hand and the muscles of the flexor forearm compartment had normal morphology. Although muscular anomalies in the hypothenar region have been described, the muscular variant described here was distinct in its origin and size from those previously reported. Knowledge of anomalous muscles in the hand has important clinical significance in routine surgery and in determining associated pathology.
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Affiliation(s)
- S Wingerter
- Department of Cell Biology and Anatomy, New York Medical College, Valhalla, New York, USA
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Le S, Connors TJ, Maroney AC. c-Jun N-terminal kinase specifically phosphorylates p66ShcA at serine 36 in response to ultraviolet irradiation. J Biol Chem 2001; 276:48332-6. [PMID: 11602589 DOI: 10.1074/jbc.m106612200] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [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: 11/06/2022] Open
Abstract
Mice lacking expression of the p66 isoform of the ShcA adaptor protein (p66(ShcA)) are less susceptible to oxidative stress and have an extended life span. Specifically, phosphorylation of p66(ShcA) at serine 36 is critical for the cell death response elicited by oxidative damage. We sought to identify the kinase(s) responsible for this phosphorylation. Utilizing the SH-SY5Y human neuroblastoma cell model, it is demonstrated that p66(ShcA) is phosphorylated on serine/threonine residues in response to UV irradiation. Both c-Jun N-terminal kinases (JNKs) and p38 mitogen-activated protein kinases are activated by UV irradiation, and we show that both are capable of phosphorylating serine 36 of p66(ShcA) in vitro. However, treatment of cells with a multiple lineage kinase inhibitor, CEP-1347, that blocks UV-induced JNK activation, but not p38, phosphatidylinositol 3-kinase, or MEK1 inhibitors, prevented p66(ShcA) phosphorylation in SH-SY5Y cells. Consistent with this finding, transfected activated JNK1, but not the kinase-dead JNK1, leads to phosphorylation of serine 36 of p66(ShcA) in Chinese hamster ovary cells. In conclusion, JNKs are the kinases that phosphorylate serine 36 of p66(ShcA) in response to UV irradiation in SH-SY5Y cells, and blocking p66(ShcA) phosphorylation by intervening in the JNK pathway may prevent cellular damage due to light-induced oxidative stress.
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Affiliation(s)
- S Le
- Cephalon, Inc., West Chester, Pennsylvania 19380, USA
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Park GY, Le S, Park KH, Le CT, Kim YW, Han SK, Shim YS, Yoo CG. Anti-inflammatory effect of adenovirus-mediated IkappaBalpha overexpression in respiratory epithelial cells. Eur Respir J 2001; 18:801-9. [PMID: 11757631 DOI: 10.1183/09031936.01.00099801] [Citation(s) in RCA: 14] [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: 11/05/2022]
Abstract
Many studies into basic biological characteristics of inflammation and tissue injury have implicated pro-inflammatory cytokine-mediated tissue injury in the pathogenesis of inflammatory lung diseases. Because transcription of most proinflammatory cytokines is dependent on the activation of nuclear factor (NF)-kappaB, NF-kappaB could be a good potential target to suppress the cytokine cascade. Cytokine-induced activation of NF-kappaB requires phosphorylation and subsequent degradation of IkappaBa. Therefore, the blocking NF-kappaB activation by IkappaBalpha could inhibit the pro-inflammatory cytokine-induced tissue injury. To evaluate whether blocking of NF-kappaB activation shows an anti-inflammatory effect, this study investigated the effect of adenovirus-mediated overexpression of IkappaBalpha super-repressor (IkappaBalpha-SR) on the pro-inflammatory cytokine expression in respiratory epithelial cells. The transduction efficiency of adenovirus was >90% in both A549 and NCI-H157 cells. Ad5IkappaBalpha-SR-transduced cells expressed high levels of IkappaBalpha-SR, which was resistant to tumour necrosis factor (TNF)-alpha-induced degradation. Adenovirus-mediated overexpression of IkappaBalpha-SR blocked cytokine-induced nuclear translocation of p65 and NF-kappaB deoxyribonucleic acid binding activity without affecting total cellular expression level of NF-kappaB. Ad5IkappaBalpha-SR transduction suppressed cytokine-induced interleukin-8 and TNF-alpha expressions at both ribonucleic acid and protein levels. These results suggest that blocking the nuclear factor-kappaB pathway by adenovirus-mediated overexpression of IkappaBalpha-super-repressor shows an effective anti-inflammatory effect in respiratory epithelial cells.
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Affiliation(s)
- G Y Park
- Dept of Internal Medicine, Seoul National University College of Medicine, Chongno-Gu, Korea
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Halliday GM, Le S. Transforming growth factor-beta produced by progressor tumors inhibits, while IL-10 produced by regressor tumors enhances, Langerhans cell migration from skin. Int Immunol 2001; 13:1147-54. [PMID: 11526095 DOI: 10.1093/intimm/13.9.1147] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [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: 11/13/2022] Open
Abstract
The induction of epidermal immunity depends on activation of local dendritic cells (DC), Langerhans cells (LC), to migrate from the skin to local lymph nodes and mature into potent immunostimulatory cells. We have previously shown that progressor skin tumors, which evade immunological destruction, prevent contact sensitizer-induced LC migration from the skin to draining lymph nodes. In contrast, regressor tumors, which evoke protective immunity, did not inhibit DC mobilization. In this study we utilized the skin explant model to determine the factors produced by skin tumors which regulate LC migration from the skin. Supernatants from two progressor squamous cell carcinoma lines both inhibited LC migration, whereas supernatants from two regressor squamous cell carcinoma lines both enhanced LC mobilization. Transforming growth factor (TGF)-beta1 inhibited, while IL-10 enhanced, LC migration from cultured skin. Both reduced the ability of LC to mature into potent allostimulators. Antibody neutralization identified that TGF-beta1 produced by the progressor tumor was responsible for inhibition of LC migration, while IL-10 produced by the regressor tumor enhanced LC mobilization. Thus these studies show that skin tumors influence DC mobilization from tumors by production of cytokines, and that TGF-beta1 is one factor produced by tumors which can immobilize LC and keep them in an immature form. This is likely to be an important mechanism of tumor escape from the immune system as progressor tumors inhibited, while regressor tumors enhanced DC mobilization.
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Affiliation(s)
- G M Halliday
- Department of Medicine (Dermatology), Melanoma and Skin Cancer Research, Institute of the University of Sydney at Royal Prince Alfred Hospital, Sydney, NSW 2006, Australia
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Abstract
Telomerase plays a crucial role in telomere maintenance in vivo. To understand telomerase regulation, we have been characterizing components of the enzyme. To date several components of the mammalian telomerase holoenzyme have been identified: the essential RNA component (human telomerase RNA [hTR]), the catalytic subunit human telomerase reverse transcriptase (hTERT), and telomerase-associated protein 1. Here we describe the identification of two new proteins that interact with hTR: hStau and L22. Antisera against both proteins immunoprecipitated hTR, hTERT, and telomerase activity from cell extracts, suggesting that the proteins are associated with telomerase. Both proteins localized to the nucleolus and cytoplasm. Although these proteins are associated with telomerase, we found no evidence of their association with each other or with telomerase-associated protein 1. Both hStau and L22 are more abundant than TERT. This, together with their localization, suggests that they may be associated with other ribonucleoprotein complexes in cells. We propose that these two hTR-associated proteins may play a role in hTR processing, telomerase assembly, or localization in vivo.
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Affiliation(s)
- S Le
- Department of Molecular Biology and Genetics, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Abstract
Telomere length is maintained by the de novo addition of telomere repeats by telomerase, yet recombination can elongate telomeres in the absence of telomerase. When the yeast telomerase RNA component, TLC1, is deleted, telomeres shorten and most cells die. However, gene conversion mediated by the RAD52 pathway allows telomere lengthening in rare survivor cells. To further investigate the role of recombination in telomere maintenance, we assayed telomere length and the ability to generate survivors in several isogenic DNA recombination mutants, including rad50, rad51, rad52, rad54, rad57, xrs2, and mre11. The rad51, rad52, rad54, and rad57 mutations increased the rate of cell death in the absence of TLC1. In contrast, although the rad50, xrs2, and mre11 strains initially had short telomeres, double mutants with tlc1 did not affect the rate of cell death, and survivors were generated at later times than tlc1 alone. While none of the double mutants of recombination genes and tlc1 (except rad52 tlc1) blocked the ability to generate survivors, a rad50 rad51 tlc1 triple mutant did not allow the generation of survivors. Thus RAD50 and RAD51 define two separate pathways that collaborate to allow cells to survive in the absence of telomerase.
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Affiliation(s)
- S Le
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Abstract
OBJECTIVE Telomerase activity, which is undetectable in most mature normal tissues, has been identified in many types of human cancers, including neuroblastomas and oligodendrogliomas. These findings suggest that a novel mechanism in addition to activation of oncogenes and inactivation of tumor suppressor genes may play an important role in tumorigenesis. The goal of the present study was to assess and correlate the telomerase activity in astrocytic gliomas of different grades. METHODS Telomere repeat amplification protocol and Southern blot hybridization with telomere-specific probes were used to detect telomerase activity and to measure terminal restriction fragment length, respectively. RESULTS Telomerase activity was detected in 3 of 9 (33%) low-grade astrocytomas (World Health Organization Grade II), 5 of 11 (45%) anaplastic astrocytomas (World Health Organization Grade III), 36 of 41 (89%) glioblastomas multiforme (World Health Organization Grade IV), 3 of 4 (75%) oligodendrogliomas, and none of 4 normal brain specimens. CONCLUSION We demonstrated that telomerase activity is absent in normal brain tissues while present in most glioma samples (72%). The frequency of such activity increases with malignancy. These results suggest that telomerase activity may be used as a tumor marker and that the activation of telomerase may correlate with initiation and malignant progression of astrocytic tumors.
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Affiliation(s)
- S Le
- Cold Spring Harbor Laboratory, New York, USA
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Abstract
Two new yeast genes, ASF1 (Anti-Silencing Function) and ASF2, as well as a C-terminal fragment of SIR3, were identified as genes that derepressed the silent mating type loci when overexpressed. ASF2 overexpression caused a greater derepression than did ASF1. ASF1 overexpression also weakened repression of genes near telomeres, but, interestingly, ASF2 had no effect on telomeric silencing. Sequences of these two genes revealed open reading frames of 279 and 525 amino acids for ASF1 and ASF2, respectively. The ASF1 protein was evolutionarily conserved, MCB motifs, sequences commonly present upstream of genes transcribed specifically in S phase, were found in front of both genes, and, indeed, both genes were transcribed specifically in the S phase of the cell cycle. While an asf2 mutant was viable and had no obvious phenotypes, an asf1 mutant grew poorly. Neither mutant exhibited derepression of the silent mating type loci. The asf1 mutant was sensitive to methyl methane sulfonate, slightly UV-sensitive and somewhat deficient in minichromosome maintenance. It also lowered the restrictive temperature of a cdc13ts mutant. These phenotypes suggested a role for ASF1 in DNA repair and chromosome maintenance.
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Affiliation(s)
- S Le
- Department of Biochemistry and Cell Biology, State University of New York at Stony Brook 11794, USA
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Chen-Cleland TA, Smith MM, Le S, Sternglanz R, Allfrey VG. Nucleosome structural changes during derepression of silent mating-type loci in yeast. J Biol Chem 1993; 268:1118-24. [PMID: 8419318] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Mutant a and alpha yeast cells were created with histone H3 containing cysteine in place of alanine 110. Because transcriptionally active nucleosomes "unfold" to reveal the histone H3-thiol groups at the center of the core, the active nucleosomes of the mutant strain can be isolated by mercury-affinity chromatography. We compared the unbound and mercury-bound nucleosomes of haploid H3-mutant strains expressing either the MAT alpha or the MATa mating-type locus. In a MAT alpha strain, the Hg-bound nucleosomes are enriched in MAT alpha DNA but lack the DNA of the transcriptionally silent HMRa mating-type locus. Conversely, in a MATa strain, the Hg-bound nucleosomes are enriched in MATa DNA sequences but deficient in HML alpha DNA. When the SIR3 gene, known to be required for silencing of the repressed mating-type loci, is mutated in the MAT alpha strain, transcription of the HMRa ensues, and its nucleosomes, as well as those of the MAT alpha locus, are retained by the organomercurial column. It follows that derepression of the silent mating-type locus, caused by the sir3 null mutation, is accompanied by an unfolding of its nucleosomes to reveal the histone H3 SH groups at their centers. Nucleosomes of the pheromone-encoding gene MFA2, a gene that is expressed in MATa cells but not in MAT alpha cells, are bound to the organomercurial column when isolated from MATa cells but not from MAT alpha cells. Thus, there is a good correlation between nucleosome unfolding and the renewed transcriptional activity at mating-type loci, and at MFA2, which had been silenced for prolonged periods. A close temporal correlation between nucleosome refolding and the cessation of transcription is not always observed in yeast, however, in contrast to observations in mammalian cells. For example, nucleosomes of the GAL1 gene are maintained in a "poised" or "primed" thiol-reactive state even when the gene is not being transcribed (Chen, T. A., Smith, M. M., Le, S., Sternglanz, R., and Allfrey, V. G. (1991) J. Biol. Chem. 266, 6489-6498). It follows that the unfolding of the nucleosome cores of the yeast H3 mutant is regulated by factors that are not temporally linked to the recruitment or traverse of the RNA polymerase complex, but which may determine the rate at which different domains of chromatin adapt to the need for transcription of the associated DNA sequences.
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Affiliation(s)
- T A Chen-Cleland
- Laboratory of Cell Biology, Rockefeller University, New York, New York 10021
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Chen-Cleland T, Smith M, Le S, Sternglanz R, Allfrey V. Nucleosome structural changes during derepression of silent mating-type loci in yeast. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)54049-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Abstract
1. Met-enkephalin is degraded by peptidases present in the hemolymph fluid and hemocyte membrane suspension of Mytilus edulis. Degradation of Met-enkephalin is rapid in the fluid and slower in the membrane. 2. Aminopeptidase activity is bestatin sensitive in hemocyte membrane and highest in the fluid of the hemolymph, which appears to have a component which is insensitive to inhibitor. 3. ACE activity is found only in the fluid of the hemolymph. 4. Carboxypeptidase and NEP (CD10: "enkephalinase") are membrane bound and the former appears to predominate. Phosphoramidon inhibits not only NEP, as expected, but the invertebrate carboxypeptidase as well.
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Affiliation(s)
- M K Leung
- Department of Chemistry, State University of New York/Old Westbury 11568-0210
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Abstract
This study was initiated to detect possible changes in beta-endorphin (beta-EP) levels of the hypothalamus, anterior pituitary gland, and peripheral blood of rats after ovariectomy and estrogen administration. Attempts were also made to determine the correlation between peripheral and central levels of beta-EP. Twenty-six Sprague-Dawley rats were decapitated. Nine had intact ovaries (Gr. INT), and 17 were ovariectomized 3 weeks before they were killed. Nine of the ovariectomized rats received estradiol benzoate (EB) (Gr. EB) and the other 8 received peanut oil (Gr. OVX) prior to the decapitation. A beta-EP radioimmunoassay was used to analyze homogenates of the hypothalamus and anterior pituitary, and peripheral blood. In the hypothalamus, beta-EP levels were significantly lower in Gr. INT and Gr. EB than in Gr. OVX. In the pituitary gland and peripheral blood, beta-EP levels were significantly higher in Gr. INT than in Gr. OVX. Pituitary beta-EP levels did not vary between Gr. OVX and Gr. EB, although beta-EP levels in peripheral blood were significantly higher in Gr. EB than in Gr. OVX. No significant correlations were noted in beta-EP levels between the hypothalamus, pituitary gland, and peripheral blood in either Gr. INT, Gr. OVX, or Gr. EB. It appears that EB exerts different effects on beta-EP levels in the hypothalamus, anterior pituitary gland, and peripheral blood, and that beta-EP levels in these regions may be independent of one another.
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Affiliation(s)
- S Le
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston 77051
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Singh P, Le S, Beauchamp RD, Townsend CM, Thompson JC. Inhibition of pentagastrin-stimulated up-regulation of gastrin receptors and growth of mouse colon tumor in vivo by proglumide, a gastrin receptor antagonist. Cancer Res 1987; 47:5000-4. [PMID: 3621187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We have recently demonstrated that gastrin stimulates growth of mouse colon cancer (MC-26) in vivo by regulation of gastrin receptors (GR). In the present study, we have tested the effect of proglumide (PGL), a GR antagonist, on the trophic and GR-regulatory effects of gastrin on MC-26 tumors. Four groups of 12 mice each were inoculated with 5 X 10(4) MC-26 cells and given injections of either normal saline (control), pentagastrin (PG), PGL, or both PG + PGL for 21 days. At the end of the treatment period, body, tumor, fundic, and colon weights were noted and GR measured. Two types of specific gastrin-binding sites were found on tumor cell membranes of control mice, one with high binding affinity (Kd = less than 1.0 nM) and low capacity (GR), and the other with a very high capacity and a low affinity (Kd = greater than 0.1 microM) (type 2 gastrin-binding sites). Only the type 1 GR were observed on the fundic mucosal and colon membranes. PG treatment resulted in a significant weight increase of the tumors with an up-regulation of only type 1 GR. On the other hand, PG had no significant effect on fundic mucosal and colonic GR levels, but caused a significant increase in fundic mucosal weights. PGL completely inhibited both the trophic and GR up-regulatory effects of PG on tumors, but incompletely reduced the PG-stimulated fundic mucosal weight gain, indicating differential sensitivity of tumor and normal tissues to PGL. PGL, in the absence of PG, was slightly trophic for normal fundic mucosa, but had no effect on MC-26 tumors and normal colon. The one striking effect of PGL, in the presence of PG, was the significant lowering of the binding affinity of type 1 GR for gastrin on both the tumor and normal gastrointestinal tissues. This effect may be another mechanism by which PGL interferes with the actions of PG on MC-26 tumors and fundic mucosa of mice.
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Kleinfeld M, Peter S, Le S. Transient hypoglycemic paraparetic syndrome in an elderly patient. J Natl Med Assoc 1987; 79:447-9. [PMID: 3108515 PMCID: PMC2625493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
An elderly diabetic patient sustained a transient hypoglycemic paraparetic episode that was attributed to inappropriate administration of glyburide. There were no other predisposing causes to account for the transient hypoglycemia. The predominant clinical signs were paraparesis of the lower extremities, with the right side more affected than the left. The patient's paraparesis cleared within two hours after administration of 50 mL of 50 percent glucose intravenously.The management of a paraparetic syndrome should include an appraisal of all the predisposing factors and their correction. The mechanism that was deemed responsible for the patient's transient hypoglycemic paraparetic syndome was loss of cerebrovascular autoregulation in a vulnerable area (the vertebral-basilar artery distribution). In the elderly patient tight control of blood glucose levels should be avoided in view of the potential development of hypoglycemia and brain injury.
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