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Smith CC, Stevens J, Novelli M, Maskey D, Sutherland GT. Phosphatidylethanol in post-mortem brain: Correlation with blood alcohol concentration and alcohol use disorder. Alcohol 2024; 119:17-22. [PMID: 38763230 DOI: 10.1016/j.alcohol.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 05/15/2024] [Accepted: 05/15/2024] [Indexed: 05/21/2024]
Abstract
Phosphatidylethanol (PEth) is an alcohol derivative that has been employed as a blood-based biomarker for regular alcohol use. This study investigates the utility of phosphatidylethanol (PEth) as a biomarker for assessing alcohol consumption in post-mortem brain tissue. Using samples from the New South Wales Brain Tissue Resource Centre, we analysed PEth(16:0/18:1) levels in the cerebellum and meninges of individuals with varying histories of alcohol use, including those diagnosed with alcohol use disorder (AUD) and controls. Our findings demonstrate a significant correlation between PEth levels and blood alcohol content (BAC) at the time of death, supporting the biomarker's sensitivity to recent alcohol intake. Furthermore, this study explores the potential of PEth levels in differentiating AUD cases from controls, taking into consideration the complexities of diagnosing AUD post-mortem. The study also examined the relationship between PEth levels and liver pathology, identifying a link with the severity of liver damage. These results underscore the value of PEth as a reliable indicator of alcohol consumption and its potential contributions to post-mortem diagnostics and consequently, research into alcohol-related brain damage.
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Affiliation(s)
- Caine C Smith
- New South Wales Brain Tissue Research Centre, Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
| | - Julia Stevens
- New South Wales Brain Tissue Research Centre, Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
| | - Mario Novelli
- New South Wales Brain Tissue Research Centre, Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
| | - Dhiraj Maskey
- New South Wales Brain Tissue Research Centre, Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
| | - Greg T Sutherland
- New South Wales Brain Tissue Research Centre, Charles Perkins Centre and School of Medical Sciences, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia.
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2
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de Bejczy A. Phosphatidylethanol (B-PEth) and other direct and indirect biomarkers of alcohol consumption. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2024; 175:313-344. [PMID: 38555120 DOI: 10.1016/bs.irn.2024.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
When identifying, preventing and treating alcohol use disorder, a correct estimation of alcohol intake is essential. An objective marker is preferred as self-reported alcohol intake suffers from bias, and the use of alcohol biomarkers is increasing globally. An easy-to-use blood biomarker to correctly assess alcohol consumption is an invaluable asset in alcohol treatment strategies, as well as in alcohol research studies. The specific, cumulative, biomarker phosphatidylethanol, mirroring the past two weeks of consumption, has shown superiority over traditional biomarkers and is an attractive choice of proxy for alcohol intake.
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Affiliation(s)
- Andrea de Bejczy
- Addiction Biology Unit, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Addiction and Dependency, Sahlgrenska University Hospital, Gothenburg, Sweden.
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3
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Pandey S, Hu Y, Anderson PL, Kiser JJ, Cooks RG. Miniature mass spectrometer-based point-of-care assay for measuring phosphatidylethanol in blood. Analyst 2023; 148:1430-1436. [PMID: 36892479 PMCID: PMC10061498 DOI: 10.1039/d3an00098b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
We demonstrate proof-of-concept for point-of-care assessment of long-term alcohol consumption by measuring phosphatidylethanol in blood/dried blood spots with nano-electrospray ionization and MS/MS using a miniature mass spectrometer. 'Abstinence', 'moderate', and 'chronic' consumption could be distinguished rapidly for both sample types, and quantitative performance was obtained with blood (LoQ-100 ng mL-1).
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Affiliation(s)
- Sangeeta Pandey
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
| | - Yanyang Hu
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
| | - Peter L Anderson
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO 80045, USA.
| | - Jennifer J Kiser
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, CO 80045, USA.
| | - R Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
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4
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Årving A, Hilberg T, Sovershaev M, Bogstrand ST, Høiseth G. Falsely low phosphatidylethanol may be associated with biomarkers of haemolytic disease. Basic Clin Pharmacol Toxicol 2023; 132:223-230. [PMID: 36370095 PMCID: PMC10098851 DOI: 10.1111/bcpt.13814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 11/03/2022] [Accepted: 11/09/2022] [Indexed: 11/13/2022]
Abstract
AIMS Falsely lower or even negative phosphatidylethanol (PEth) levels may theoretically be seen in patients with haemolytic diseases, and the present study aimed to elucidate this hypothesis. METHODS PEth and carbohydrate-deficient transferrin (CDT) from 9893 serum and whole blood samples were included along with markers of haemolysis (i.e. haptoglobin, HbA1c, reticulocytes, LD and Hb). Cases showing discrepancy between PEth and CDT, that is, a low PEth value and a high CDT value, were considered to be possibly caused by falsely lowered PEth despite high alcohol consumption. These cases (N = 233) were compared to the control group without PEth and CDT mismatch. RESULTS The levels of haptoglobin were significantly lower in the cases showing low PEth and high CDT (estimate = -0.62, p = 0.002). The levels of HbA1c (estimate = -3.26, p = 0.001) and Hb (estimate = -0.507, p < 0.001) were also significantly lower in this group. These findings indicate haemolytic diseases in the low PEth/high CDT group. There were no significant differences for reticulocytes and LD concentrations between the low PEth/high CDT group and the control group. CONCLUSIONS These results indicate that falsely low PEth values could be associated with markers of haemolytic diseases, although more research is needed to highlight this further.
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Affiliation(s)
- Alexander Årving
- Department of Forensic Sciences, Oslo University Hospital, Oslo, Norway
| | | | | | | | - Gudrun Høiseth
- Department of Forensic Sciences, Oslo University Hospital, Oslo, Norway.,Norwegian Centre for Addiction Research (SERAF), Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Center for Psychopharmacology, Diakonhjemmet Hospital, Oslo, Norway
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5
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Quantitative determination of phosphatidylethanol in dried blood spots for monitoring alcohol abstinence. Nat Protoc 2020; 16:283-308. [PMID: 33288956 DOI: 10.1038/s41596-020-00416-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 09/21/2020] [Indexed: 12/19/2022]
Abstract
Phosphatidylethanol (PEth), which is formed by enzymatic reaction between ethanol and phosphatidylcholine, is a direct marker for alcohol usage. PEth has a long elimination half-life (~5-10 d) and specimens can be sampled using minimally invasive microsampling strategies. In combination with rapid analysis procedures PEth has proved to be advantageous for the detection of abstinence over other direct (e.g., ethyl glucuronide in blood, urine or hair) and indirect (e.g., carbohydrate-deficient transferrin in serum) alcohol markers. Although PEth determination is widely applied around the world, laboratory protocols are not standardized. Here we provide general guidelines for the analysis of PEth in dried blood spots (DBSs), including reference material evaluation, synthesis of a deuterated internal standard, preparation of calibration samples (reference material in teetotaller blood), and analyte separation and detection. The protocol contains information to extract the DBSs either manually or with a fully automated autosampler. Extraction of the analytes from DBS filter paper cards is performed using an organic extraction, followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). For accurate and reliable measurement of PEth, the two most abundant analogs, PEth 16:0/18:1 and PEth 16:0/18:2, are quantified. We show data that provide guidelines on how to interpret the results for both demographic studies and forensic applications. The described protocol can be applied by experienced laboratory staff with basic LC-MS/MS knowledge and takes 2 d to perform.
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Årving A, Høiseth G, Hilberg T, Trydal T, Husa A, Djordjevic A, Kabashi S, Vindenes V, Bogstrand ST. Comparison of the Diagnostic Value of Phosphatidylethanol and Carbohydrate‐Deficient Transferrin as Biomarkers of Alcohol Consumption. Alcohol Clin Exp Res 2020; 45:153-162. [DOI: 10.1111/acer.14503] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 10/26/2020] [Accepted: 10/29/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Alexander Årving
- From the Department of Forensic Sciences (AÅ, GH, SK, VV, STB) Oslo University Hospital Oslo Norway
| | - Gudrun Høiseth
- From the Department of Forensic Sciences (AÅ, GH, SK, VV, STB) Oslo University Hospital Oslo Norway
- Faculty of Medicine (GH, SK, VV) Institute of Clinical Medicine University of Oslo Oslo Norway
| | - Thor Hilberg
- Fürst Medisinsk Laboratorium (TH, TT, AH, AD) Oslo Norway
| | - Torleif Trydal
- Fürst Medisinsk Laboratorium (TH, TT, AH, AD) Oslo Norway
| | - Asgeir Husa
- Fürst Medisinsk Laboratorium (TH, TT, AH, AD) Oslo Norway
| | | | - Saranda Kabashi
- From the Department of Forensic Sciences (AÅ, GH, SK, VV, STB) Oslo University Hospital Oslo Norway
- Faculty of Medicine (GH, SK, VV) Institute of Clinical Medicine University of Oslo Oslo Norway
| | - Vigdis Vindenes
- From the Department of Forensic Sciences (AÅ, GH, SK, VV, STB) Oslo University Hospital Oslo Norway
- Faculty of Medicine (GH, SK, VV) Institute of Clinical Medicine University of Oslo Oslo Norway
| | - Stig Tore Bogstrand
- From the Department of Forensic Sciences (AÅ, GH, SK, VV, STB) Oslo University Hospital Oslo Norway
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7
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Röhricht M, Paschke K, Sack PM, Weinmann W, Thomasius R, Wurst FM. Phosphatidylethanol Reliably and Objectively Quantifies Alcohol Consumption in Adolescents and Young Adults. Alcohol Clin Exp Res 2020; 44:2177-2186. [PMID: 32981101 DOI: 10.1111/acer.14464] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/14/2020] [Indexed: 11/30/2022]
Abstract
BACKGROUND Alcohol contributes to numerous annual deaths and various societal problems not just in adult, but also in adolescent, populations. Therefore, it is vital to find methods for reliably detecting alcohol use for early preventative measures. Research has shown phosphatidylethanol (PEth) to be superior to self-report instruments and indirect biomarkers for alcohol consumption in adult populations. However, the transferability onto an adolescent population has not yet been investigated. METHODS N = 106 adolescents and young adults aged between 13 and 21 years were included. PEth analysis using high-pressure liquid chromatography-tandem mass spectrometry was performed on dried blood spot samples. Self-report questionnaires for alcohol consumption (Alcohol Use Disorders Identification Test-Consumption, AUDIT-C, and Timeline Followback, TLFB) and drug and alcohol consumption (Detection of Alcohol and Drug Problems in Adolescents, DEP-ADO) were completed by each participant. RESULTS AUDIT-C scores showed large correlations with PEth 16:0/18:1 (rs = 0.732) and PEth 16:0/18:2 (rs = 0.661) concentrations. AUDIT-C with a cutoff value ≥3 was largely correlated with PEth 16:0/18:1 (η = 0.411) and showed a medium-sized correlation with PEth 16:0/18:2 (η = 0.397) concentrations. Using an AUDIT-C cutoff value ≥5 showed large correlations with both PEth 16:0/18:1 (η = 0.510) and PEth 16:0/18:2 (η = 0.497) concentrations, respectively. ROC curves indicated higher PEth concentrations are a good model for detecting positive AUDIT-C cutoff values (AUROC range: 0.800 to 0.849). PEth concentrations showed medium to large correlations with DEP-ADO and TLFB subscales (range rs = 0.469 to 0.746). CONCLUSION The results suggest that PEth is a reliable and objective marker for quantifying alcohol consumption in adolescents and young adults. This could be of importance for early preventative measures against hazardous alcohol consumption, which is increasingly common at younger ages.
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Affiliation(s)
- Milan Röhricht
- From the, German Center for Addiction Research in Childhood and Adolescence (DZSKJ), (MR, KP, PMS, RT), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Kerstin Paschke
- From the, German Center for Addiction Research in Childhood and Adolescence (DZSKJ), (MR, KP, PMS, RT), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Peter-Michael Sack
- From the, German Center for Addiction Research in Childhood and Adolescence (DZSKJ), (MR, KP, PMS, RT), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Wolfgang Weinmann
- Institute of Forensic Medicine, (WW), University of Bern, Bern, Switzerland
| | - Rainer Thomasius
- From the, German Center for Addiction Research in Childhood and Adolescence (DZSKJ), (MR, KP, PMS, RT), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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8
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Ramenskaia GV, Melnik EV, Petukhov AE. [Phospholipase D: its role in metabolism processes and disease development]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2019; 64:84-93. [PMID: 29460838 DOI: 10.18097/pbmc20186401084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Phospholipase D (PLD) is one of the key enzymes that catalyzes the hydrolysis of cell membrane phospholipids. In this review current knowledge about six human PLD isoforms, their structure and role in physiological and pathological processes is summarized. Comparative analysis of PLD isoforms structure is presented. The mechanism of the hydrolysis and transphosphatidylation performed by PLD is described. The PLD1 and PLD2 role in the pathogenesis of some cancer, infectious, thrombotic and neurodegenerative diseases is analyzed. The prospects of PLD isoform-selective inhibitors development are shown in the context of the clinical usage and the already-existing inhibitors are characterized. Moreover, the formation of phosphatidylethanol (PEth), the alcohol abuse biomarker, as the result of PLD-catalyzed phospholipid transphosphatidylation is considered.
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Affiliation(s)
- G V Ramenskaia
- Sechenov First Moscow State Medical University (Sechenovskiy University), Moscow, Russia
| | - E V Melnik
- Sechenov First Moscow State Medical University (Sechenovskiy University), Moscow, Russia
| | - A E Petukhov
- Sechenov First Moscow State Medical University (Sechenovskiy University), Moscow, Russia; Moscow Research and Practical Centre for Narcology, Moscow, Russia
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9
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Luginbühl M, Weinmann W, Butzke I, Pfeifer P. Monitoring of direct alcohol markers in alcohol use disorder patients during withdrawal treatment and successive rehabilitation. Drug Test Anal 2019; 11:859-869. [DOI: 10.1002/dta.2567] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 12/21/2018] [Accepted: 12/28/2018] [Indexed: 12/17/2022]
Affiliation(s)
- Marc Luginbühl
- Institute of Forensic MedicineUniversity of Bern Switzerland
| | | | - Ingo Butzke
- Hospital of Psychiatry Münsingen Münsingen Switzerland
| | - Philippe Pfeifer
- Hospital of Psychiatry Münsingen Münsingen Switzerland
- University Hospital of Psychiatry BernUniversity of Bern Bern Switzerland
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10
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Schröck A, Henzi A, Bütikofer P, König S, Weinmann W. Determination of the formation rate of phosphatidylethanol by phospholipase D (PLD) in blood and test of two selective PLD inhibitors. Alcohol 2018; 73:1-7. [PMID: 30103144 DOI: 10.1016/j.alcohol.2018.03.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 03/08/2018] [Accepted: 03/13/2018] [Indexed: 11/29/2022]
Abstract
Phosphatidylethanol (PEth) is an alcohol biomarker formed from phosphatidylcholine (PC) by the enzyme phospholipase D (PLD) in the presence of ethanol. A drinking study revealed individual differences in maximum PEth levels after drinking to a targeted blood alcohol concentration (BAC) of 0.1%. This seemed to be due to different PLD activities in the tested persons. Furthermore, post-sampling formation of PEth occurred in blood samples, still containing alcohol. Therefore, a standardized in vitro test for measuring individual PEth formation rates was developed. Two PLD inhibitors were tested for their potency to inhibit post-sampling PEth formation. PEth-negative blood samples were collected from a volunteer. Ethanol was added in different concentrations (0.01-0.3% BAC) directly after blood sampling. The specimens were incubated at 37 °C. Aliquots were taken at the start of the incubation, and every hour until 8 h after start of incubation, and one sample was taken on subsequent days over 1 week. PEth 16:0/18:1 and PEth 16:0/18:2 were determined by online SPE-LC-MS/MS. Furthermore, this test system was applied to blood samples of 12 volunteers. For the inhibition tests, fresh blood (spiked with 0.1% ethanol) was spiked with 30, 300, 3000, or 30,000 nM of either halopemide or 5-fluoro-2-indolyl-deschlorohalopemide (FIPI), and incubated at 37 °C. PEth concentrations were determined hourly over 5 h on the first day and once on day 2 and day 3. PEth formation was linear in the first 7 h of incubation and dependent on the alcohol concentration. The formation rates of PEth 16:0/18:1 were 0.002 μmol L-1 h-1 (0.01% BAC), 0.016 μmol L-1 h-1 (0.1% BAC), 0.025 μmol L-1 h-1 (0.2% BAC), and 0.029 μmol L-1 h-1 (0.3% BAC). For PEth 16:0/18:2, the formation rates were 0.002 μmol L-1 h-1 (0.01% BAC), 0.019 μmol L-1 h-1 (0.1% BAC), 0.025 μmol L-1 h-1 (0.2% BAC), and 0.030 μmol L-1 h-1 (0.3% BAC). Maximum concentrations reached 431 ng/mL (PEth 16:0/18:1) and 496 ng/mL (PEth 16:0/18:2) at 0.3% BAC after 3 days. Maximum velocity (vmax) was not reached under these conditions. PEth formation in blood of the 12 volunteers ranged between 0.011 and 0.025 μmol L-1 h-1 for PEth 16:0/18:1 and between 0.014 and 0.021 μmol L-1 h-1 for PEth 16:0/18:2. PEth formation in human blood was inhibited by halopemide in a concentration-dependent manner. However, a complete inhibition was not achieved by the applied maximum concentration of 30,000 nM. FIPI showed a better inhibition of PEth formation. A complete inhibition could be achieved by a concentration of 30,000 nM for the first 24 h (for PEth 16:0/18:1) and for 48 h (for PEth 16:0/18:2). Formation of PEth was found to be dependent on the BAC. As a consequence, it is essential to inhibit PLD activity after blood collection to avoid post-sampling formation of PEth in blood samples with a positive BAC. Inhibition of PEth formation was more effective using FIPI, compared to halopemide.
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Affiliation(s)
- Alexandra Schröck
- Institute of Forensic Medicine, Forensic Toxicology and Chemistry, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, c/o Theodor Kocher Institute, Freiestrasse 1, 3012 Bern, Switzerland
| | - Anna Henzi
- Institute of Forensic Medicine, Forensic Toxicology and Chemistry, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland
| | - Peter Bütikofer
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland
| | - Stefan König
- Institute of Forensic Medicine, Forensic Toxicology and Chemistry, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland
| | - Wolfgang Weinmann
- Institute of Forensic Medicine, Forensic Toxicology and Chemistry, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland.
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Hulsebus HJ, Curtis BJ, Molina PE, Afshar M, Boule LA, Morris N, Keshavarzian A, Kolls JK, Yeligar SM, Price ME, Wyatt TA, Choudhry MA, Kovacs EJ. Summary of the 2017 Alcohol and Immunology Research Interest Group (AIRIG) meeting. Alcohol 2018; 69:51-56. [PMID: 29654985 PMCID: PMC5930121 DOI: 10.1016/j.alcohol.2017.10.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 10/20/2017] [Accepted: 10/23/2017] [Indexed: 02/08/2023]
Abstract
On June 24, 2017, the 22nd annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held as a satellite conference during the annual Research Society on Alcoholism (RSA) Scientific Meeting in Denver, Colorado. The 2017 meeting focused broadly on mechanisms that link alcohol to tissue injury and inflammation, and how this research can be translated to improve human health. Two plenary sessions composed the meeting, which first explored the association between alcohol and trauma/tissue injury, and finished with a discussion of alcohol and mucosal inflammation. The presentations encompassed diverse areas of alcohol research, from effects on the brain, to airway and pulmonary systems, to gut barrier disruption. The discussions also thoughtfully highlighted how current laboratory and clinical research can be used to prevent or treat alcohol-related morbidity and mortality.
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Affiliation(s)
- Holly J. Hulsebus
- Department of Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA,Alcohol Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA,Immunology Graduate Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Brenda J. Curtis
- Department of Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA,Alcohol Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Patricia E. Molina
- Department of Physiology and Alcohol and Drug Abuse Center of Excellence, Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Majid Afshar
- Division of Pulmonary and Critical Care Medicine, Loyola University Chicago, Maywood, IL, USA,Alcohol Research Program, Burn and Shock Trauma Research Institute, Department of Surgery, Loyola University Chicago Health Sciences Campus, Maywood, IL, USA
| | - Lisbeth A. Boule
- Department of Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA,Alcohol Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA
| | - Niya Morris
- Alcohol Research Program, Burn and Shock Trauma Research Institute, Department of Surgery, Loyola University Chicago Health Sciences Campus, Maywood, IL, USA,Integrative Cell Biology Program, Loyola University Chicago Health Sciences Campus, Maywood, IL, USA
| | - Ali Keshavarzian
- Department of Gastroenterology, Rush University Medical Center, Chicago, IL, USA
| | - Jay K. Kolls
- Center for Translational Research in Infection and Inflammation, Tulane University, New Orleans, LA, USA
| | - Samantha M. Yeligar
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep, Emory University and Atlanta Veterans Affairs Medical Center, Decatur, GA, USA
| | - Michael E. Price
- Department of Internal Medicine, Division of Pulmonary, Critical Care, Sleep and Allergy, University of Nebraska Medical Center, Omaha, NE, USA
| | - Todd A. Wyatt
- Department of Internal Medicine, Division of Pulmonary, Critical Care, Sleep and Allergy, University of Nebraska Medical Center, Omaha, NE, USA
| | - Mashkoor A. Choudhry
- Alcohol Research Program, Burn and Shock Trauma Research Institute, Department of Surgery, Loyola University Chicago Health Sciences Campus, Maywood, IL, USA,Integrative Cell Biology Program, Loyola University Chicago Health Sciences Campus, Maywood, IL, USA
| | - Elizabeth J. Kovacs
- Department of Surgery, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA,Alcohol Research Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA,Immunology Graduate Program, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA,Corresponding author: Elizabeth J. Kovacs, Ph.D., 12700 East 19th Ave, Research Complex 2, Mailstop #8620, Aurora, CO, 80045. Phone: 303-724-8243.
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12
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Simon TW. Providing context for phosphatidylethanol as a biomarker of alcohol consumption with a pharmacokinetic model. Regul Toxicol Pharmacol 2018; 94:163-171. [DOI: 10.1016/j.yrtph.2018.01.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Revised: 12/29/2017] [Accepted: 01/30/2018] [Indexed: 10/18/2022]
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13
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Barrio P, Teixidor L, Ortega L, Lligoña A, Rico N, Bedini JL, Vieta E, Gual A. Filling the gap between lab and clinical impact: An open randomized diagnostic trial comparing urinary ethylglucuronide and ethanol in alcohol dependent outpatients. Drug Alcohol Depend 2018; 183:225-230. [PMID: 29291550 DOI: 10.1016/j.drugalcdep.2017.11.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 11/02/2017] [Accepted: 11/03/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND Efforts aimed at reducing alcohol-related harm include early detection of risky drinkers as well as detection of early relapse in patients with alcohol dependence. Ethyl glucuronide (EtG) has been proven to be a reliable biomarker for the detection of recent drinking; however, no randomized, diagnostic trial to date has tested its impact on drinking outcomes. The aim of this study was to assess, in a randomized design, the implications of EtG screening on alcohol outcomes, compared to screening with a low sensitivity biomarker such as ethanol. METHODS Alcohol dependent outpatients were randomized to either 24 weeks of continuous screening with EtG or ethanol. Patients were aware of screening methods and results. After 24 weeks, all participants were screened with EtG. Self-reports were also gathered. A logistic regression compared the rate of EtG positive results at study end between groups. Generalized estimating equations evaluated the descending monthly rate of EtG positive patients in the EtG group. RESULTS A total of 162 patients were randomized. During the study period, the ethanol group showed less patients with positive screens (19/64 (29.7%) vs 58/98 (59%)). After 24 weeks, the EtG group showed a greater number of patients having a negative screening test compared to ethanol subjects when they were all screened with EtG (5/62 (8.1%) vs 13/39 (33.3%)). A significant decrease in the rate of EtG positive patients was found for the first three months of the study. CONCLUSIONS Routine screening with EtG seems to reduce drinking and improve abstinence rates in alcohol dependent outpatients.
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Affiliation(s)
- Pablo Barrio
- Addictive Behaviors Unit, Clinical Neuroscience Institute, Clinic Hospital, Villarroel 170 08036, Barcelona, Spain; Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Casanova 143 08036 Barcelona, Spain; Grup de Recerca en Addiccions Clínic, Hospital Clínic de Barcelona, IDIBAPS, Universitat de Barcelona, Red de Trastornos adictivos (RETICS), Villarroel 170 08036 Barcelona, Spain.
| | - Lídia Teixidor
- Addictive Behaviors Unit, Clinical Neuroscience Institute, Clinic Hospital, Villarroel 170 08036, Barcelona, Spain; Grup de Recerca en Addiccions Clínic, Hospital Clínic de Barcelona, IDIBAPS, Universitat de Barcelona, Red de Trastornos adictivos (RETICS), Villarroel 170 08036 Barcelona, Spain
| | - Lluisa Ortega
- Addictive Behaviors Unit, Clinical Neuroscience Institute, Clinic Hospital, Villarroel 170 08036, Barcelona, Spain; Grup de Recerca en Addiccions Clínic, Hospital Clínic de Barcelona, IDIBAPS, Universitat de Barcelona, Red de Trastornos adictivos (RETICS), Villarroel 170 08036 Barcelona, Spain
| | - Anna Lligoña
- Addictive Behaviors Unit, Clinical Neuroscience Institute, Clinic Hospital, Villarroel 170 08036, Barcelona, Spain; Grup de Recerca en Addiccions Clínic, Hospital Clínic de Barcelona, IDIBAPS, Universitat de Barcelona, Red de Trastornos adictivos (RETICS), Villarroel 170 08036 Barcelona, Spain
| | - Nayra Rico
- Department of Biochemistry, Hospital Clinic Barcelona, Spain
| | | | - Eduard Vieta
- Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Casanova 143 08036 Barcelona, Spain; Centro de Investigación en Red de Salud mental (CIBERSAM), Pabellón 11, 28029, Madrid, Spain; Bipolar Disorder Program, Institute of Neuroscience, Hospital Clínic, University of Barcelona, IDIBAPS, Villarroel 170 08036 Barcelona, Spain
| | - Antoni Gual
- Addictive Behaviors Unit, Clinical Neuroscience Institute, Clinic Hospital, Villarroel 170 08036, Barcelona, Spain; Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Casanova 143 08036 Barcelona, Spain; Grup de Recerca en Addiccions Clínic, Hospital Clínic de Barcelona, IDIBAPS, Universitat de Barcelona, Red de Trastornos adictivos (RETICS), Villarroel 170 08036 Barcelona, Spain
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McCaul ME, Wand GS. Detecting Deception in Our Research Participants: Are Your Participants Who You Think They Are? Alcohol Clin Exp Res 2017; 42:230-237. [PMID: 29286543 DOI: 10.1111/acer.13556] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 11/09/2017] [Indexed: 12/20/2022]
Abstract
There is increasing awareness of the potential negative impacts of participant deception on research, including possibly undermining reliability and reproducibility of study findings. These deceptive individuals set their personal interests above the rules of study participation, thereby jeopardizing data quality as well as placing themselves and others at risk. The costs of participant deception are numerous. Overall, it reduces statistical power and may even result in false conclusions about efficacy and safety. To date, most studies have not utilized sufficient methods to detect rule-breaking subjects. The purpose of this article is to bring to the attention of alcohol and other drug researchers issues involving deceptive participants. The review will suggest alcohol-specific as well as more general strategies to identify and thereby minimize enrollment of these deceptive participants. Specifically, we will identify strategies that are employed in different phases of human alcohol research and advance approaches that may be helpful to the field in reducing these contaminants. As a field, we need to be more proactive in identifying the deceptive participant even at the cost of more burdensome study enrollment. In light of the systemic nature and multipronged damage that this emerging pattern of deception inflicts on clinical research, it is imperative that we each assume greater responsibility for our role in mitigating this source of research contamination.
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Affiliation(s)
- Mary E McCaul
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Medicine , The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Gary S Wand
- Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland.,Department of Medicine , The Johns Hopkins University School of Medicine, Baltimore, Maryland
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15
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Luginbühl M, Willem S, Schürch S, Weinmann W. Formation of phosphatidylethanol from endogenous phosphatidylcholines in animal tissues from pig, calf, and goat. Forensic Sci Int 2017; 283:211-218. [PMID: 29324350 DOI: 10.1016/j.forsciint.2017.12.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/12/2017] [Accepted: 12/16/2017] [Indexed: 11/29/2022]
Abstract
In the presence of alcohol, phosphatidylcholine (PC) is transformed to the direct alcohol biomarker phosphatidylethanol (PEth). This reaction is catalyzed by the enzyme phospholipase D (PLD) and dependent on substrate availability. As recent methods have solely focused on the determination of PEth, information about the PC composition was generally missing. To address this issue and monitor PC (16:0/18:1 and 16:0/18:2) and PEth (16:0/18:1 and 16:0/18:2) simultaneously, a reversed phase LC-MS/MS method based on a C8 core-shell column, coupled to a Sciex 5500 QTrap instrument was developed. By application of polarity switching, at first, PC was measured in ESI positive SRM mode, while PEth was determined at a later stage in ESI negative SRM mode. The PEth method was validated for human blood samples to show its robustness and subsequently applied for the investigation of systematic in vitro PEth formation in animal tissue samples (brain, kidney, liver, and blood) from a pig, a calf, and a goat. Homogenized tissue was incubated at 37°C with varying ethanol concentrations from 1 to 7g/kg (determined by HS-GC-FID) for 5h, whereby a sample was taken every 30min. For all tissue samples, an increase in PEth was measurable. PEth concentrations formed in blood remained below the LLOQ, in agreement with literature. Data analysis of Michaelis-Menten kinetics and PC within the tissue provided a detailed insight about PEth formation, as the occurrence of PEth species can be linked to the observed PC composition. The results of this study show that PEth formation rates vary from tissue to tissue and among different species. Furthermore, new recommendations for PEth analysis are presented.
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Affiliation(s)
- Marc Luginbühl
- Institute of Forensic Medicine, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland
| | - Sytske Willem
- Laboratory of Toxicology, University of Ghent, FFW - 4th Floor, Ottergemsesteenweg 460, 9000 Gent, Belgium
| | - Stefan Schürch
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Wolfgang Weinmann
- Institute of Forensic Medicine, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland.
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16
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Luginbühl M, König S, Schürch S, Weinmann W. Evaluation of N-acetyltaurine as an ethanol marker in human blood. Alcohol 2017; 65:11-18. [PMID: 29084624 DOI: 10.1016/j.alcohol.2017.05.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 05/23/2017] [Accepted: 05/26/2017] [Indexed: 12/01/2022]
Abstract
To investigate the potential of N-acetyltaurine (NAcT) in blood as a biomarker for alcohol uptake, a previously published LC-MS/MS method for urine was modified to simultaneously detect NAcT and ethyl glucuronide (EtG). The method was applied in a drinking study and by analyzing 147 forensic case samples. In the drinking study, contrary to EtG, NAcT proved to be an endogenous substance, which was present at 22 ± 7 ng/mL (13-31 ng/mL) in the blood after 2 weeks of abstinence. A moderate increase in NAcT to 40 ± 10 ng/mL (27-57 ng/mL) was observed after drinking. Within 24 h, the NAcT concentrations declined to starting concentrations in seven out of eight subjects. Peak EtG concentrations (c¯max) of 445 ± 101 ng/mL (278-662 ng/mL) were reached. While EtG in blood can be used to detect alcohol consumption even if ethanol is already eliminated, some of the maximum NAcT concentrations after a single ethanol dose were in the range of endogenous levels detected prior to the start of drinking in other subjects. In the 147 blood samples, the following concentrations were found: blood alcohol concentration (BAC): 1.22 ± 0.95 g/kg (0-3.46 g/kg); NAcT: 37.8 ± 18.4 ng/mL (12.1-109 ng/mL); EtG: 1149 ± 1121 ng/mL (0-5950 ng/mL). ROC curve analysis for BAC thresholds at 0.8 and 1.6 g/kg were performed for EtG and NAcT. Due to the presence of endogenous NAcT levels resulting in a lower sensitivity and selectivity when compared to EtG, and due to a minor increase in concentration after alcohol uptake, the usefulness of NAcT as an alcohol biomarker in blood is very limited.
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Affiliation(s)
- Marc Luginbühl
- Institute of Forensic Medicine, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland
| | - Stefan König
- Institute of Forensic Medicine, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland
| | - Stefan Schürch
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland
| | - Wolfgang Weinmann
- Institute of Forensic Medicine, University of Bern, Bühlstrasse 20, 3012 Bern, Switzerland.
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17
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Petukhov AE, Nadezhdin AV, Bogstrand ST, Bryun EA, Ramenskaya GV, Koshkina EA, Mel'nik EV, Smirnov AV, Tetenova EY. [The comparative analysis of the methods for the determination of phosphatidylethanol in blood as a biological marker of alcohol abuse]. Sud Med Ekspert 2017; 60:23-26. [PMID: 28980550 DOI: 10.17116/sudmed201760523-26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The confirmation of the fact of alcohol abuse is currently an important problem of both medical and social significance. Of all biological markers of alcohol consumption presently in use, blood phosphatidylethanol (PEth) is considered to be most sensitive and specific one. Therefore it has promising prospects for the further application. There is no universally accepted method for the calculation of the phosphatidylethanol concentration in human blood. For this reason, the present article places emphasis on the comparative characteristic of various methods for the determination of this substance.
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Affiliation(s)
- A E Petukhov
- Moscow Research and Practical Narcological Centre, Moscow Health Department, Moscow, Russia, 109390; A.P. Arzamastsev Department of Pharmaceutical and Toxicological Chemistry, I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia, 119991
| | - A V Nadezhdin
- Moscow Research and Practical Narcological Centre, Moscow Health Department, Moscow, Russia, 109390
| | | | - E A Bryun
- Moscow Research and Practical Narcological Centre, Moscow Health Department, Moscow, Russia, 109390
| | - G V Ramenskaya
- A.P. Arzamastsev Department of Pharmaceutical and Toxicological Chemistry, I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia, 119991
| | - E A Koshkina
- Moscow Research and Practical Narcological Centre, Moscow Health Department, Moscow, Russia, 109390
| | - E V Mel'nik
- A.P. Arzamastsev Department of Pharmaceutical and Toxicological Chemistry, I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia, 119991
| | - A V Smirnov
- Moscow Research and Practical Narcological Centre, Moscow Health Department, Moscow, Russia, 109390
| | - E Yu Tetenova
- Moscow Research and Practical Narcological Centre, Moscow Health Department, Moscow, Russia, 109390
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18
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Afshar M, Burnham EL, Joyce C, Clark BJ, Yong M, Gaydos J, Cooper RS, Smith GS, Kovacs EJ, Lowery EM. Cut-Point Levels of Phosphatidylethanol to Identify Alcohol Misuse in a Mixed Cohort Including Critically Ill Patients. Alcohol Clin Exp Res 2017; 41:1745-1753. [PMID: 28792620 PMCID: PMC5626634 DOI: 10.1111/acer.13471] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 08/02/2017] [Indexed: 01/16/2023]
Abstract
BACKGROUND Although alcohol misuse is associated with deleterious outcomes in critically ill patients, its detection by either self-report or examination of biomarkers is difficult to obtain consistently. Phosphatidylethanol (PEth) is a direct alcohol biomarker that can characterize alcohol consumption patterns; however, its diagnostic accuracy in identifying misuse in critically ill patients is unknown. METHODS PEth values were obtained in a mixed cohort comprising 122 individuals from medical and burn intensive care units (n = 33), alcohol detoxification unit (n = 51), and healthy volunteers (n = 38). Any alcohol misuse and severe misuse were referenced by Alcohol Use Disorders Identification Test (AUDIT) and AUDIT-C scores separately. Mixed-effects logistic regression analysis was performed, and the discrimination of PEth was evaluated using the area under the receiver-operating characteristic (ROC) curve. RESULTS The area under the ROC curve for PEth was 0.927 (95% CI: 0.877, 0.977) for any misuse and 0.906 (95% CI: 0.850, 0.962) for severe misuse defined by AUDIT. By AUDIT-C, the area under the ROC curves was 0.948 (95% CI: 0.910, 0.956) for any misuse and 0.913 (95% CI: 0.856, 0.971) for severe misuse. The PEth cut-points of ≥250 and ≥400 ng/ml provided optimal discrimination for any misuse and severe misuse, respectively. The positive predictive value for ≥250 ng/ml was 88.7% (95% CI: 77.5, 95.0), and the negative predictive value was 86.7% (95% CI: 74.9, 93.7). PEth ≥ 400 ng/ml achieved similar values, and similar results were shown for AUDIT-C. In a subgroup analysis of critically ill patients only, test characteristics were similar to the mixed cohort. CONCLUSIONS PEth is a strong predictor and has good discrimination for any and severe alcohol misuse in a mixed cohort that includes critically ill patients. Cut-points at 250 ng/ml for any, and 400 ng/ml for severe, are favorable. External validation will be required to establish these cut-points in critically ill patients.
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Affiliation(s)
- Majid Afshar
- Burn and Shock Trauma Research Institute, Stritch School of Medicine, Loyola University Health Sciences Campus, Maywood, IL
- Alcohol Research Program, Stritch School of Medicine, Loyola University Health Sciences Campus, Maywood, IL
- Department of Public Health Sciences, Stritch School of Medicine, Loyola University Chicago Health Sciences Campus, Maywood, IL
| | - Ellen L. Burnham
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, CO
| | - Cara Joyce
- Department of Public Health Sciences, Stritch School of Medicine, Loyola University Chicago Health Sciences Campus, Maywood, IL
| | - Brendan J. Clark
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, CO
| | - Meagan Yong
- Burn and Shock Trauma Research Institute, Stritch School of Medicine, Loyola University Health Sciences Campus, Maywood, IL
- Alcohol Research Program, Stritch School of Medicine, Loyola University Health Sciences Campus, Maywood, IL
| | - Jeannette Gaydos
- Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine, Aurora, CO
| | - Richard S. Cooper
- Department of Public Health Sciences, Stritch School of Medicine, Loyola University Chicago Health Sciences Campus, Maywood, IL
| | - Gordon S. Smith
- Shock Trauma and Anesthesiology Research (STAR) – Organized Research Center, Department of Surgery, University of Maryland, Baltimore, Maryland
| | - Elizabeth J. Kovacs
- Department of Surgery, University of Colorado School of Medicine, Aurora, CO
| | - Erin M. Lowery
- Burn and Shock Trauma Research Institute, Stritch School of Medicine, Loyola University Health Sciences Campus, Maywood, IL
- Alcohol Research Program, Stritch School of Medicine, Loyola University Health Sciences Campus, Maywood, IL
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19
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Schröck A, Wurst FM, Thon N, Weinmann W. Assessing phosphatidylethanol (PEth) levels reflecting different drinking habits in comparison to the alcohol use disorders identification test - C (AUDIT-C). Drug Alcohol Depend 2017. [PMID: 28645063 DOI: 10.1016/j.drugalcdep.2017.04.026] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In addition to monitoring problematic or harmful alcohol consumption, drinking experiments indicated the potential of phosphatidylethanols (PEth) in abstinence monitoring. To date, no profound evaluation of thresholds for the differentiation of abstinence from moderate drinking and for detection of excessive consumption based on PEth homologues exists. Investigations with a large group of healthy volunteers (n=300) were performed to establish PEth reference values reflecting different drinking habits. Blood samples were analyzed for PEth 16:0/18:1 and 16:0/18:2 by online-SPE-LC-MS/MS method. Results were compared to AUDIT-C questionnaires, to the amounts of alcohol consumed during the two-weeks prior to blood sampling, and were statistically evaluated. PEth concentrations were significantly correlated with self-reported alcohol consumption (r>0.69) and with AUDIT-C scores (r>0.65). 4.0% of 300 volunteers reported abstinence (AUDIT-C score: 0), no PEth was detectable in their blood. PEth 16:0/18:1 concentrations below the limit of detection of 10.0ng/mL match with abstinence and light drinking habits (≤10g pure alcohol/day). However, some volunteers classified as "excessive alcohol consumers" had negative PEth results. In the group of volunteers classified as "moderate drinkers" (AUDIT-C score: 1-3 (women) and 1-4 (men)), 95% of the test persons had PEth 16:0/18:1 ranging from not detected to 112ng/mL, and PEth 16:0/18:2 ranging from not detected to 67.0ng/mL. Combination of self-reported alcohol consumption and AUDIT-C score showed that negative PEth results match with abstinence or light drinking. Moderate alcohol consumption resulted in PEth 16:0/18:1 from 0 to 112ng/mL and for PEth 16:0/18:2 ranged from 0 to 67.0ng/mL. Higher PEth concentrations indicated excessive alcohol consumption.
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Affiliation(s)
- Alexandra Schröck
- Institute of Forensic Medicine, Forensic Toxicology and Chemistry, University of Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences, University of Bern, Switzerland
| | - Friedrich M Wurst
- Center for Interdisciplinary Addiction Research Hamburg, Germany; University of Basel, Basel, Switzerland
| | - Natasha Thon
- Paracelsus Medical University, Salzburg, Austria
| | - Wolfgang Weinmann
- Institute of Forensic Medicine, Forensic Toxicology and Chemistry, University of Bern, Switzerland.
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20
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Introduction of sample tubes with sodium azide as a preservative for ethyl glucuronide in urine. Int J Legal Med 2017; 131:1283-1289. [DOI: 10.1007/s00414-017-1633-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 07/04/2017] [Indexed: 10/19/2022]
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21
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Wang S, Yang R, Ji F, Li H, Dong J, Chen W. Sensitive and precise monitoring of phosphatidylethanol in human blood as a biomarker for alcohol intake by ultrasound-assisted dispersive liquid-liquid microextraction combined with liquid chromatography tandem mass spectrometry. Talanta 2017; 166:315-320. [DOI: 10.1016/j.talanta.2017.01.083] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 01/24/2017] [Accepted: 01/29/2017] [Indexed: 01/15/2023]
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22
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McCaul ME, Hutton HE, Stephens MAC, Xu X, Wand GS. Anxiety, Anxiety Sensitivity, and Perceived Stress as Predictors of Recent Drinking, Alcohol Craving, and Social Stress Response in Heavy Drinkers. Alcohol Clin Exp Res 2017; 41:836-845. [PMID: 28281290 PMCID: PMC5388456 DOI: 10.1111/acer.13350] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 02/06/2017] [Indexed: 12/15/2022]
Abstract
BACKGROUND Stress and anxiety are widely considered to be causally related to alcohol craving and consumption, as well as development and maintenance of alcohol use disorder (AUD). However, numerous preclinical and human studies examining effects of stress or anxiety on alcohol use and alcohol-related problems have been equivocal. This study examined relationships between scores on self-report anxiety, anxiety sensitivity, and stress measures and frequency and intensity of recent drinking, alcohol craving during early withdrawal, as well as laboratory measures of alcohol craving and stress reactivity among heavy drinkers with AUD. METHODS Media-recruited, heavy drinkers with AUD (N = 87) were assessed for recent alcohol consumption. Anxiety and stress levels were characterized using paper-and-pencil measures, including the Beck Anxiety Inventory (BAI), the Anxiety Sensitivity Index-3 (ASI-3), and the Perceived Stress Scale (PSS). Eligible subjects (N = 30) underwent alcohol abstinence on the Clinical Research Unit; twice daily measures of alcohol craving were collected. On day 4, subjects participated in the Trier Social Stress Test; measures of cortisol and alcohol craving were collected. RESULTS In multivariate analyses, higher BAI scores were associated with lower drinking frequency and reduced drinks/drinking day; in contrast, higher ASI-3 scores were associated with higher drinking frequency. BAI anxiety symptom and ASI-3 scores also were positively related to Alcohol Use Disorders Identification Test total scores and AUD symptom and problem subscale measures. Higher BAI and ASI-3 scores but not PSS scores were related to greater self-reported alcohol craving during early alcohol abstinence. Finally, BAI scores were positively related to laboratory stress-induced cortisol and alcohol craving. In contrast, the PSS showed no relationship with most measures of alcohol craving or stress reactivity. CONCLUSIONS Overall, clinically oriented measures of anxiety compared with perceived stress were more strongly associated with a variety of alcohol-related measures in current heavy drinkers with AUD.
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Affiliation(s)
- Mary E McCaul
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Heidi E Hutton
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Mary Ann C Stephens
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Xiaoqiang Xu
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Gary S Wand
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Heier C, Xie H, Zimmermann R. Nonoxidative ethanol metabolism in humans-from biomarkers to bioactive lipids. IUBMB Life 2016; 68:916-923. [PMID: 27714979 PMCID: PMC5324703 DOI: 10.1002/iub.1569] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 09/19/2016] [Indexed: 12/21/2022]
Abstract
Ethanol is a widely used psychoactive drug whose chronic abuse is associated with organ dysfunction and disease. Although the prevalent metabolic fate of ethanol in the human body is oxidation a smaller fraction undergoes nonoxidative metabolism yielding ethyl glucuronide, ethyl sulfate, phosphatidylethanol and fatty acid ethyl esters. Nonoxidative ethanol metabolites persist in tissues and body fluids for much longer than ethanol itself and represent biomarkers for the assessment of ethanol intake in clinical and forensic settings. Of note, the nonoxidative reaction of ethanol with phospholipids and fatty acids yields bioactive compounds that affect cellular signaling pathways and organelle function and may contribute to ethanol toxicity. Thus, despite low quantitative contributions of nonoxidative pathways to overall ethanol metabolism the resultant ethanol metabolites have important biological implications. In this review we summarize the current knowledge about the enzymatic formation of nonoxidative ethanol metabolites in humans and discuss the implications of nonoxidative ethanol metabolites as biomarkers of ethanol intake and mediators of ethanol toxicity. © 2016 IUBMB Life, 68(12):916-923, 2016.
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Affiliation(s)
- Christoph Heier
- Institute of Molecular Biosciences, University of GrazAustria
| | - Hao Xie
- Institute of Molecular Biosciences, University of GrazAustria
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Philip F, Ha EE, Seeliger MA, Frohman MA. Measuring Phospholipase D Enzymatic Activity Through Biochemical and Imaging Methods. Methods Enzymol 2016; 583:309-325. [PMID: 28063496 DOI: 10.1016/bs.mie.2016.09.041] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The phospholipase D (PLD) enzymatic superfamily regulates a wide range of cell biological and physiological pathways, including platelet activation, immune responses, cancer, and spermatogenesis. The three main enzymatic actions of the superfamily entail (i) hydrolyzing membrane phospholipids (phosphatidylcholine (PC) and cardiolipin) to generate choline and the second messenger signaling lipid phosphatidic acid (PA), (ii) using ethanol to transphosphatidylate PC to generate the long-lived metabolite phosphatidylethanol, and (iii) hydrolyzing RNA transcripts to generate piRNAs, the third form of endogenous RNAi. We discuss briefly previously published methods for in vitro and in vivo detection and imaging of PA, and focus on production, purification, and in vitro endonuclease activity analysis for human PLD6, a mitochondrial-tethered isoform with roles in fertility, cancer, and neuronal homeostasis.
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Affiliation(s)
- F Philip
- Center for Developmental Genetics, Stony Brook University School of Medicine, Stony Brook, NY, United States
| | - E E Ha
- Center for Developmental Genetics, Stony Brook University School of Medicine, Stony Brook, NY, United States
| | - M A Seeliger
- Center for Developmental Genetics, Stony Brook University School of Medicine, Stony Brook, NY, United States
| | - M A Frohman
- Center for Developmental Genetics, Stony Brook University School of Medicine, Stony Brook, NY, United States.
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25
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Phosphatidylethanol (PEth) detected in blood for 3 to 12 days after single consumption of alcohol—a drinking study with 16 volunteers. Int J Legal Med 2016; 131:153-160. [DOI: 10.1007/s00414-016-1445-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 08/26/2016] [Indexed: 10/21/2022]
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26
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N-Acetyltaurine as a novel urinary ethanol marker in a drinking study. Anal Bioanal Chem 2016; 408:7529-36. [DOI: 10.1007/s00216-016-9855-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/07/2016] [Accepted: 08/01/2016] [Indexed: 11/25/2022]
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27
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Kummer N, Wille SMR, Poll A, Lambert WEE, Samyn N, Stove CP. Quantification of EtG in hair, EtG and EtS in urine and PEth species in capillary dried blood spots to assess the alcohol consumption in driver's licence regranting cases. Drug Alcohol Depend 2016; 165:191-7. [PMID: 27364378 DOI: 10.1016/j.drugalcdep.2016.06.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Revised: 04/29/2016] [Accepted: 06/04/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND In Belgium, the analysis of indirect biomarkers such as carbohydrate deficient transferrin (CDT%), gamma-glutamyltransferase (GGT), aspartate aminotransferase/alanine aminotransferase (AST/ALT) and mean corpuscular volume (MCV), is currently used to monitor the alcohol consumption in cases of fitness to drive assessment. We evaluated the use of direct ethanol markers for this purpose, exclusively determined in matrices obtained via non- or minimally invasive sampling. METHODS Three validated quantitative methods (ethylglucuronide (EtG) in hair and urine, ethylsulfate (EtS) in urine, and phosphatidylethanol species (PEth 16:0/18:1, PEth 18:1/18:1 and PEth 16:0/16:0) in capillary dried blood spots (C-DBS)) were used. Fifty volunteers, for whom fitness to drive had to be assessed and for whom a blood analysis for indirect biomarkers was requested, were included in the study. The sampling and analysis of hair, urine and C-DBS were added to the process currently used. RESULTS Hair EtG (24/50) and C-DBS PEths (29/50) are more sensitive than the currently used indirect biomarkers (13/50 for CDT%) to detect excessive and chronic alcohol consumption and allow to disprove an abstinence period. Urinary EtG and EtS are useful parameters to determine recent alcohol consumption. CONCLUSION The combined use of the three strategies allows better inference about the evolution of the alcohol consumption prior to the sampling. Moreover, the exclusive use of non- or minimally invasive sampling (hair, urine and C-DBS) allows this to be performed directly during the fitness to drive assessment by regular staff members. This approach offers the potential to improve the Belgian driver's licence regranting process.
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Affiliation(s)
- Natalie Kummer
- Federal Public Service Justice, National Institute of Criminalistics and Criminology, Brussels, Belgium
| | - Sarah M R Wille
- Federal Public Service Justice, National Institute of Criminalistics and Criminology, Brussels, Belgium
| | | | - Willy E E Lambert
- Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Nele Samyn
- Federal Public Service Justice, National Institute of Criminalistics and Criminology, Brussels, Belgium
| | - Christophe P Stove
- Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
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Schröck A, Pfäffli M, König S, Weinmann W. Application of phosphatidylethanol (PEth) in whole blood in comparison to ethyl glucuronide in hair (hEtG) in driving aptitude assessment (DAA). Int J Legal Med 2016; 130:1527-1533. [DOI: 10.1007/s00414-016-1394-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/24/2016] [Indexed: 01/01/2023]
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Alternative sampling strategies for the assessment of alcohol intake of living persons. Clin Biochem 2016; 49:1078-91. [PMID: 27208822 DOI: 10.1016/j.clinbiochem.2016.05.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 04/28/2016] [Accepted: 05/01/2016] [Indexed: 01/16/2023]
Abstract
Monitoring of alcohol consumption by living persons takes place in various contexts, amongst which workplace drug testing, driving under the influence of alcohol, driving licence regranting programs, alcohol withdrawal treatment, diagnosis of acute intoxication or fetal alcohol ingestion. The matrices that are mostly used today include blood, breath and urine. The aim of this review is to present alternative sampling strategies that allow monitoring of the alcohol consumption in living subjects. Ethanol itself, indirect (carbohydrate deficient transferrin, CDT%) as well as direct biomarkers (ethyl glucuronide, EtG; ethyl sulphate, EtS; fatty acid ethyl esters, FAEEs and phosphatidylethanol species, PEths) of ethanol consumption will be considered. This review covers dried blood spots (CDT%, EtG/EtS, PEths), dried urine spots (EtG/EtS), sweat and skin surface lipids (ethanol, EtG, FAEEs), oral fluid (ethanol, EtG), exhaled breath (PEths), hair (EtG, FAEEs), nail (EtG), meconium (EtG/EtS, FAEEs), umbilical cord and placenta (EtG/EtS and PEth 16:0/18:1). Main results, issues and considerations specific to each matrix are reported. Details about sample preparation and analytical methods are not within the scope of this review.
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Determination of fatty acid ethyl esters in dried blood spots by LC-MS/MS as markers for ethanol intake: application in a drinking study. Anal Bioanal Chem 2016; 408:3503-9. [PMID: 26968564 DOI: 10.1007/s00216-016-9426-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Revised: 02/05/2016] [Accepted: 02/16/2016] [Indexed: 10/22/2022]
Abstract
The forensic utility of fatty acid ethyl esters (FAEEs) in dried blood spots (DBS) as short-term confirmatory markers for ethanol intake was examined. An LC-MS/MS method for the determination of FAEEs in DBS was developed and validated to investigate FAEE formation and elimination in a drinking study, whereby eight subjects ingested 0.66-0.84 g/kg alcohol to reach blood alcohol concentrations (BAC) of 0.8 g/kg. Blood was taken every 1.5-2 h, BAC was determined, and dried blood spots were prepared, with 50 μL of blood, for the determination of FAEEs. Lower limits of quantitation (LLOQ) were between 15 and 37 ng/mL for the four major FAEEs. Validation data are presented in detail. In the drinking study, ethyl palmitate and ethyl oleate proved to be the two most suitable markers for FAEE determination. Maximum FAEE concentrations were reached in samples taken 2 or 4 h after the start of drinking. The following mean peak concentrations (c̅(max)) were reached: ethyl myristate 14 ± 4 ng/mL, ethyl palmitate 144 ± 35 ng/mL, ethyl oleate 125 ± 55 ng/mL, ethyl stearate 71 ± 21 ng/mL, total FAEEs 344 ± 91 ng/mL. Detectability of FAEEs was found to be on the same time scale as BAC. In liquid blood samples containing ethanol, FAEE concentrations increase post-sampling. This study shows that the use of DBS fixation prevents additional FAEE formation in blood samples containing ethanol. Positive FAEE results obtained by DBS analysis can be used as evidence for the presence of ethanol in the original blood sample.
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Kummer N, Ingels AS, Wille SMR, Hanak C, Verbanck P, Lambert WEE, Samyn N, Stove CP. Quantification of phosphatidylethanol 16:0/18:1, 18:1/18:1, and 16:0/16:0 in venous blood and venous and capillary dried blood spots from patients in alcohol withdrawal and control volunteers. Anal Bioanal Chem 2015; 408:825-38. [PMID: 26597914 DOI: 10.1007/s00216-015-9169-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 10/28/2015] [Accepted: 11/02/2015] [Indexed: 01/30/2023]
Abstract
Phosphatidylethanol species (PEths) are promising biomarkers of alcohol consumption. Here, we report on the set-up, validation, and application of a novel UHPLC-ESI-MS/MS method for the quantification of PEth 16:0/18:1, PEth 18:1/18:1, and PEth 16:0/16:0 in whole blood (30 μL) and in venous (V, 30 μL) or capillary (C, 3 punches (3 mm)) dried blood spots (DBS). The methods were linear from 10 (LLOQ) to 2000 ng/mL for PEth 16:0/18:1, from 10 (LLOQ) to 1940 ng/mL for PEth 18:1/18:1, and from 19 (LLOQ) to 3872 ng/mL for PEth 16:0/16:0. Extraction efficiencies were higher than 55% (RSD < 18%) and matrix effects compensated for by IS were between 77 and 125% (RSD < 10%). Accuracy, repeatability, and intermediate precision fulfilled acceptance criteria (bias and RSD below 13%). Validity of the procedure for determination of PEth 16:0/18:1 in blood was demonstrated by the successful participation in a proficiency test. The quantification of PEths in C-DBS was not significantly influenced by the hematocrit, punch localization, or spot volume. The stability of PEths in V-DBS stored at room temperature was demonstrated up to 6 months. The method was applied to authentic samples (whole blood, V-DBS, and C-DBS) from 50 inpatients in alcohol withdrawal and 50 control volunteers. Applying a cut-off value to detect inpatients at 221 ng/mL for PEth 16:0/18:1 provided no false positive results and a good sensitivity (86%). Comparison of quantitative results (Bland-Altman plot, Passing-Bablok regression, and Wilcoxon signed rank test) revealed that V-DBS and C-DBS were valid alternatives to venous blood for the detection of alcohol consumption.
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Affiliation(s)
- Natalie Kummer
- Federal Public Service Justice, National Institute of Criminalistics and Criminology, Chaussée de Vilvorde 100, 1120, Brussels, Belgium
| | - Ann-Sofie Ingels
- Federal Public Service Justice, National Institute of Criminalistics and Criminology, Chaussée de Vilvorde 100, 1120, Brussels, Belgium
| | - Sarah M R Wille
- Federal Public Service Justice, National Institute of Criminalistics and Criminology, Chaussée de Vilvorde 100, 1120, Brussels, Belgium
| | - Catherine Hanak
- Laboratory of Psychological Medicine and Addictology, ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Route de Lennik 800, 1070, Brussels, Belgium
| | - Paul Verbanck
- Laboratory of Psychological Medicine and Addictology, ULB Neuroscience Institute (UNI), Université Libre de Bruxelles (ULB), Route de Lennik 800, 1070, Brussels, Belgium
| | - Willy E E Lambert
- Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Nele Samyn
- Federal Public Service Justice, National Institute of Criminalistics and Criminology, Chaussée de Vilvorde 100, 1120, Brussels, Belgium
| | - Christophe P Stove
- Laboratory of Toxicology, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium.
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Wurst FM, Thon N, Yegles M, Schrück A, Preuss UW, Weinmann W. Ethanol Metabolites: Their Role in the Assessment of Alcohol Intake. Alcohol Clin Exp Res 2015; 39:2060-72. [DOI: 10.1111/acer.12851] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 07/22/2015] [Indexed: 01/12/2023]
Affiliation(s)
- Friedrich M. Wurst
- Paracelsus Medical University; Salzburg Austria
- Center for Interdisciplinary Addiction Research; University of Hamburg; Hamburg Germany
| | | | - Michel Yegles
- Service de Toxicologie; Laboratoire National de Sante; Luxembourg Luxembourg
| | - Alexandra Schrück
- Institute of Forensic Medicine; University of Bern; Bern Switzerland
| | - Ulrich W. Preuss
- Department of Psychiatry, Psychotherapy and Psychosomatic Medicine; University of Halle; Halle Germany
| | - Wolfgang Weinmann
- Institute of Forensic Medicine; University of Bern; Bern Switzerland
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Piano MR, Tiwari S, Nevoral L, Phillips SA. Phosphatidylethanol Levels Are Elevated and Correlate Strongly with AUDIT Scores in Young Adult Binge Drinkers. Alcohol Alcohol 2015; 50:519-25. [DOI: 10.1093/alcalc/agv049] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Accepted: 04/23/2015] [Indexed: 12/18/2022] Open
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