1
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Sprega G, Kobidze G, Lo Faro AF, Pichini S, Farkas T, Tini A, Mskhiladze A, Busardò FP, Chankvetadze B. Optimization of enantioselective high-performance liquid chromatography-tandem mass spectrometry method for the quantitative determination of 3,4-methylenedioxy-methamphetamine (MDMA) and its phase-1 metabolites in human biological fluids. J Pharm Biomed Anal 2024; 243:116076. [PMID: 38430614 DOI: 10.1016/j.jpba.2024.116076] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/12/2024] [Accepted: 02/26/2024] [Indexed: 03/05/2024]
Abstract
Recently we published in this journal an enantioselective high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantitative determination of 3,4-methylenedioxymethamphetamine (MDMA) and its major phase-1 metabolites, 4-hydroxy-3-methoxyamphetamine (HMA), 4-hydroxy-3-methoxymethamphetamine (HMMA) and 3,4-methylenedioxyamphetamine (MDA) in human plasma, sweat, oral fluid and urine. Since we did not achieve simultaneous enantioseparation of all 4 compounds with a single chiral column, two amylose-based chiral columns were used alternatively. Further optimization of the mobile phase in the present study enabled baseline separation of all four pairs of enantiomers on a single Lux AMP column. In addition, by optimization of the column dimension and applied flow-rate it became possible to complete the separation within 6 minutes. These new methods were applied to the analysis of human plasma, oral fluid and urine. While results on the concentration of MDMA and its metabolites in various biological fluids were reported in our recent publication, in the present study an attempt was made to hydrolyze glucuronides in urine samples by using alternatively, hydrochloric acid or glucuronidase and to evaluate the effect of hydrolysis on the concentration and enantiomeric distribution of hydroxy metabolites of MDMA such as HMA and HMMA.
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Affiliation(s)
- Giorgia Sprega
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Giorgi Kobidze
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Alfredo Fabrizio Lo Faro
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy.
| | - Simona Pichini
- National Centre on Addiction and Doping, Istituto Superiore di Sanità, Rome, Italy
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave, Torrance, CA 90501, USA
| | - Anastasio Tini
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Antonina Mskhiladze
- Faculty of Natural Sciences, Mathematics, Technologies and Pharmacy, Sokhumi State University, Polytkovskaya 61, Tbilisi 0186, Georgia
| | - Francesco Paolo Busardò
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, I. Chavchavadze Ave 1, Tbilisi 0179, Georgia
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2
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Song JY, Farkas T. Adeno-associated virus analysis by size exclusion chromatography within 3 minutes using short bio-inert columns made with 3 µm particles operated at high flowrates. J Chromatogr A 2024; 1718:464684. [PMID: 38350350 DOI: 10.1016/j.chroma.2024.464684] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/15/2024]
Abstract
Adeno-associated virus (AAV) analytical characterization is crucial to the well-defined and reproducible production of human gene therapies utilizing the AAV vector modality. The establishment of analytical methods based upon technology platforms currently widely used by bio-therapeutic manufacturers, namely HPLC, will assist efforts to produce high quality AAV reproducibly and decrease chemical manufacturing and control challenges in method portability and reliability. AAV analysis by size exclusion chromatography (SEC) is currently practiced with columns and mobile phase conditions traditional to SEC of proteins. Here, an improved method to measure multiple AVV critical quality attributes (CQA) rapidly by SEC is explored. The use of short columns made with small particles at high flow rates resulted in up to 80 % reduction in analysis time and 66 % in sample consumption while maintaining reliable quantitation of AAV aggregate or high molecular weight (HMW) content. These results were demonstrated across four different AAV serotypes. Furthermore, critical AAV sample handling learnings are shared.
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Affiliation(s)
- James Y Song
- Phenomenex Inc., 411 Madrid Avenue, Torrance, CA 90501, USA
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Avenue, Torrance, CA 90501, USA.
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3
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Kobidze G, Sprega G, Daziani G, Balloni A, Lo Faro AF, Farkas T, Peluso P, Basile G, Busardò FP, Chankvetadze B. Separation of undeuterated and partially deuterated enantioisotopologues of some amphetamine derivatives on achiral and polysaccharide-based chiral columns in high-performance liquid chromatography. J Chromatogr A 2024; 1718:464709. [PMID: 38350352 DOI: 10.1016/j.chroma.2024.464709] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 01/29/2024] [Accepted: 02/01/2024] [Indexed: 02/15/2024]
Abstract
The different behavior of enantiomers of chiral compounds in non-isotropic environments (among them in living organism) is well known. On the other hand, the importance of a kinetic isotope effect in the biomedical field has become evident during past few decades. Thus, separation of both, enantiomers and isotopologues is now critical. Only very few published studies have attempted the simultaneous separation of enantioisotopologues. In this article we report baseline separation of partially deuterated isotopologues of a few amphetamine derivatives in high-performance liquid chromatography (HPLC) using achiral columns. In addition, the simultaneous separations of enantiomers and isotopologues (i.e. enantioisotopologues) were attempted on polysaccharide-based chiral columns. For several compounds the isotope effect was tunable and could be switched from a "normal" to "inverse" by making changes to the mobile-phase composition. A stronger isotope effect was observed in acetonitrile-containing mobile phases compared to methanol-containing ones with both chiral and achiral columns. In a separation system where both "normal" and "inverse" isotope effects were observed the "normal" isotope effect was favored in polar organic solvents while increasing content of the aqueous component in the reversed-phase (RP) mobile phase favored an "inverse" isotope effect. This observation indicates that polar, hydrogen bonding-type noncovalent interactions are involved in the "normal" isotope effect, while apolar hydrophobic-type interactions are mostly responsible for the "inverse" isotope effect.
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Affiliation(s)
- Giorgi Kobidze
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Giorgia Sprega
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Gloria Daziani
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Aurora Balloni
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Alfredo Fabrizio Lo Faro
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave., Torrance, 90501 CA, USA
| | - Paola Peluso
- Istituto di Chimica Biomolecolare ICB-CNR, Sede secondaria di Sassari, Traversa La Crucca 3, Regione Baldinca, Li Punti, 07100 Sassari, Italy
| | - Giuseppe Basile
- Department of Trauma Surgery, IRCCS Galeazzi Orthopedic Institute, Via Riccardo Galeazzi 4, 20161 Milan, Italy
| | - Francesco Paolo Busardò
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy.
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, 0179 Tbilisi, Georgia.
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4
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Lo Faro AF, Sprega G, Beradinelli D, Tini A, Poyatos L, Papaseit E, Berretta P, Di Giorgi A, Farre M, Takaishvili N, Farkas T, Busardò FP, Chankvetadze B. Development of enantioselective high-performance liquid chromatography-tandem mass spectrometry method for the quantitative determination of 3,4-methylenedioxy-methamphetamine (MDMA) and its phase-1 metabolites in human biological fluids. J Pharm Biomed Anal 2024; 238:115768. [PMID: 37979525 DOI: 10.1016/j.jpba.2023.115768] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/03/2023] [Accepted: 10/03/2023] [Indexed: 11/20/2023]
Abstract
In the present study enantioselective high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods were developed for the quantitative determination of 3,4-methylenedioxy-methamphetamine (MDMA) and its major phase-1 metabolites 4-hydroxy-3-methoxyamphetamine (HMA), 4-hydroxy-3-methoxymethamphetamine (HMMA) and 3,4-methylenedioxyamphetamine (MDA) in human plasma, sweat, oral fluid (OF) and urine. The simultaneous separation of all these compounds and their respective enantioseparation was accomplished on two polysaccharide-based chiral columns. The Lux AMP column with a proprietary chiral selector enabled baseline separation of the enantiomers of MDMA, HMA and HMMA while MDA enantiomers could not be separated with this column under the experimental conditions used in this study. The Lux i-Amylose-3 column based on amylose tris(5-chloro-3-methylphenylcarbamate) as chiral selector baseline-separated the enantiomers of MDMA, HMMA and MDA while the enantiomers of HMA could not be separated. Thus, the various samples were analyzed by using both columns alternatively in combinations with acetonitrile containing 25% (v/v) 5 mM ammonium bicarbonate buffer at pH 11.0 as mobile phase. Analysis time was less than 4 min with the Lux AMP column and less than 6 min with the Lux i-Amylose-3 column. Both methods were validated and applied to the enantioselective determination of MDMA and its phase-I metabolites in human biological fluids, and enantioselective metabolism of MDMA was confirmed.
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Affiliation(s)
- Alfredo Fabrizio Lo Faro
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Giorgia Sprega
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Diletta Beradinelli
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Anstasio Tini
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Lourdes Poyatos
- Servei de Farmacologia Clínica, Hospital Universitari Germans Trias i Pujol (HUGTiP, IGTP)- Universitat Aut`onoma de Barcelona, Unitat Docent HUGTiP, Badalona, Spain
| | - Esther Papaseit
- Servei de Farmacologia Clínica, Hospital Universitari Germans Trias i Pujol (HUGTiP, IGTP)- Universitat Aut`onoma de Barcelona, Unitat Docent HUGTiP, Badalona, Spain
| | - Paolo Berretta
- National Centre on Addiction and Doping, Istituto Superiore di Sanit`a, Rome, Italy
| | - Alessandro Di Giorgi
- National Centre on Addiction and Doping, Istituto Superiore di Sanit`a, Rome, Italy
| | - Magì Farre
- Servei de Farmacologia Clínica, Hospital Universitari Germans Trias i Pujol (HUGTiP, IGTP)- Universitat Aut`onoma de Barcelona, Unitat Docent HUGTiP, Badalona, Spain
| | - Nino Takaishvili
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, 0179 Tbilisi, Georgia
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave., Torrance 90501, CA, USA
| | - Francesco Paolo Busardò
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy.
| | - Bezhan Chankvetadze
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, 0179 Tbilisi, Georgia
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5
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Jorbenadze S, Khatiashvili T, Chelidze A, Lo Faro AF, Farkas T, Tini A, Sprega G, Berardinelli D, Busardò FP, Chankvetadze B. Development of a novel enantioselective high-performance liquid chromatography-mass spectrometry method for the differentiation of dextro- and levo-methorphan and their O-demethylated metabolites in human blood and its application to post-mortem samples. J Pharm Biomed Anal 2024; 237:115769. [PMID: 37864951 DOI: 10.1016/j.jpba.2023.115769] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/03/2023] [Accepted: 10/03/2023] [Indexed: 10/23/2023]
Abstract
Recently we proposed an isocratic enantioselective high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the separation and quantitative determination of dextro- (DXM) and levo-methorphan (LVM) and their pharmacologically relevant metabolites, dextrorphan and levorphanol, respectively, in human blood samples. This method was based on the polysaccharide-based chiral column Lux AMP, a specialty column characterized with high stability in mobile phases of pH 11.0 and above. The use of a single-source column is a limitation for any analytical method. Therefore, the major goal of the present study was to develop an enantioselective method for the differentiation of dextro- and levo-methorphan, as well as their metabolites dextrorphan and levorphanol, using Lux Cellulose-3 as alternative chiral column with methanol containing 0.1 % diethylamine mobile phase. A newly developed method uses a chiral selector part of HPLC columns available from multiple manufacturers and a fairly common mobile phase. The method was validated and applied to post-mortem blood samples. Out of 50 analyzed new samples, dextromethorphan (DXM) was detected in 17 samples. Of these 17 cases DXM was accompanied with LVM in 7 samples. The proposed analytical method is relatively simple, accurate and fast and can be adopted for routine use in forensic and clinical toxicology laboratories.
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Affiliation(s)
- Saba Jorbenadze
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi 0179, Georgia
| | - Tamar Khatiashvili
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi 0179, Georgia; Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Aluda Chelidze
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi 0179, Georgia
| | - Alfredo Fabrizio Lo Faro
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave., Torrance, CA 90501, USA
| | - Anastasio Tini
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Giorgia Sprega
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Diletta Berardinelli
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy
| | - Francesco Paolo Busardò
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona 60121, Italy.
| | - Bezhan Chankvetadze
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi 0179, Georgia.
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6
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Lo Faro AF, Sprega G, Berardinelli D, Tini A, Poyatos L, Pichini S, Farrè M, Farkas T, Busardò FP, Giunashvili L, Chankvetadze B. Development of enantioselective high-performance liquid chromatography-tandem mass spectrometry method for quantitative determination of methylone and some of its metabolites in oral fluid. J Chromatogr B Analyt Technol Biomed Life Sci 2023; 1228:123824. [PMID: 37487291 DOI: 10.1016/j.jchromb.2023.123824] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 07/05/2023] [Accepted: 07/06/2023] [Indexed: 07/26/2023]
Abstract
In the present study an enantioselective high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the first time for quantitative determination of the recreational drug of abuse methylone and its major metabolites in oral fluid. The simultaneous chemo- and enantioseparation of methylone and its major metabolites was performed on a polysaccharide-based chiral column based on amylose tris(5-chloro-3-methylphenylcarbamate) as chiral selector (Lux i-Amylose-3) with methanol containing 0.4 % (v/v) aqueous ammonium hydroxide as mobile phase. The time required for enantioselective analysis of methylone and its 2 major metabolites was 15 min. This method was fully validated following the Organization of Scientific Area Committees (OSAC) for Forensic Science guidelines. This method was applied for the enantioselective determination of methylone and its metabolites in oral fluid and enantioselectivity in metabolism and pharmacokinetic of the parent compound and metabolites was observed. While the first enantiomer of methylone was found at higher concentration, both metabolites shown greater concentration for the second enantiomer. The results revealed that MET undergoes an enantioselective biotransformation to its metabolites HMMC and MDC, with S-(-)-MET more rapidly metabolized and eliminated from the body.
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Affiliation(s)
- Alfredo Fabrizio Lo Faro
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Giorgia Sprega
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Diletta Berardinelli
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Anastasio Tini
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Lourdes Poyatos
- Servei de Farmacologia Clínica, Hospital Universitari Germans Trias i Pujol (HUGTiP, IGTP)- Universitat Autònoma de Barcelona, Unitat Docent HUGTiP, Badalona, Spain
| | - Simona Pichini
- National Centre on Addiction and Doping, Istituto Superiore di Sanità, Rome, Italy
| | - Magì Farrè
- Servei de Farmacologia Clínica, Hospital Universitari Germans Trias i Pujol (HUGTiP, IGTP)- Universitat Autònoma de Barcelona, Unitat Docent HUGTiP, Badalona, Spain
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave., Torrance, 90501 CA, USA
| | - Francesco Paolo Busardò
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy.
| | - Lasha Giunashvili
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, 0179 Tbilisi, Georgia
| | - Bezhan Chankvetadze
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, 0179 Tbilisi, Georgia
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7
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Lo Faro AF, Berardinelli D, Sprega G, Tini A, Carlier J, Farkas T, Busardò FP, Chankvetadze B. Development of an enantioselective high-performance liquid chromatography-tandem mass spectrometry method for the quantitative determination of methorphan and its O-demethylated metabolite in human blood and its application to post-mortem samples. J Pharm Biomed Anal 2023; 230:115384. [PMID: 37044005 DOI: 10.1016/j.jpba.2023.115384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 03/28/2023] [Accepted: 03/31/2023] [Indexed: 04/03/2023]
Abstract
In the present work an isocratic enantioselective high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the separation and quantitative determination of dextro - and levo -methorphan and their pharmacologically relevant metabolites, dextrorphan and levorphanol, respectively, in human blood samples. The separation of enantiomers of methorphan and metabolites was performed on the polysaccharide-based chiral column Lux AMP in combination with acetonitrile and 5 mM aqueous ammonium bicarbonate pH 11 in the ratio 50:50 (%, v/v) as mobile phase with the flow rate 1 mL/min. The mass spectrometer was operated in scheduled multiple reaction monitoring (MRM) mode, with four transitions for each dextromethorpan, levomethorphan, dextrorphan and dextromethorphan-d3 and two transitions for each levorphanol, levorphanol-d3 and dextrorphan-d3. Application of this method to human post-mortem blood samples confirmed cases of severe overdosing with dextromethorphan, levomethorphan, and less commonly with both.
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Affiliation(s)
- Alfredo Fabrizio Lo Faro
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Diletta Berardinelli
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Giorgia Sprega
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Anastasio Tini
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Jeremy Carlier
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave., Torrance, 90501 CA, USA
| | - Francesco Paolo Busardò
- Department of Excellence-Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60121 Ancona, Italy.
| | - Bezhan Chankvetadze
- Tbilisi State University, Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, 0179 Tbilisi, Georgia
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Dainichi T, Nakano Y, Doi H, Nakamizo S, Nakajima S, Farkas T, Wong P, Narang V, Traspas RM, Kawakami E, Guttman-Yassky E, Dreesen O, Litman T, Reversade B, Kabashima K. 176 C10orf99/2610528A11Rik induces keratinocyte proinflammatory response and regulates lipid metabolism and barrier formation of the skin. J Invest Dermatol 2022. [DOI: 10.1016/j.jid.2022.09.187] [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: 11/19/2022]
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9
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Hankovszky P, Tömösvári A, Hawchar F, Farkas T, Rudas L. Tachycardia dependent early repolarisation pattern in subarachnoid haemorrhage related takotsubo syndrome. J Electrocardiol 2021; 67:52-54. [PMID: 34082151 DOI: 10.1016/j.jelectrocard.2021.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/04/2021] [Accepted: 05/10/2021] [Indexed: 11/16/2022]
Abstract
We present a case of a patient who suffered subarachnoid haemorrhage (SAH), complicated by takotsubo syndrome, paroxysmal atrial fibrillation and ECG repolarisation abnormality, compatible with Brugada phenocopy. The early repolarisation morphology showed a paradox association with the cardiac cycle length; a relationship not yet documented in SAH. Our observation also sheds light on the genesis of the "spiked helmet" ECG sign.
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Affiliation(s)
- P Hankovszky
- University of Szeged, Deparment of Anesthesiology and Intensive Care, Semmelweis utca 6, 6720 Szeged, Hungary
| | - A Tömösvári
- University of Szeged, Deparment of Anesthesiology and Intensive Care, Semmelweis utca 6, 6720 Szeged, Hungary
| | - F Hawchar
- University of Szeged, Deparment of Anesthesiology and Intensive Care, Semmelweis utca 6, 6720 Szeged, Hungary
| | - T Farkas
- University of Szeged, Deparment of Anesthesiology and Intensive Care, Semmelweis utca 6, 6720 Szeged, Hungary
| | - L Rudas
- University of Szeged, Deparment of Anesthesiology and Intensive Care, Semmelweis utca 6, 6720 Szeged, Hungary.
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10
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Felletti S, De Luca C, Lievore G, Chenet T, Chankvetadze B, Farkas T, Cavazzini A, Catani M. Shedding light on mechanisms leading to convex-upward van Deemter curves on a cellulose tris(4-chloro-3-methylphenylcarbamate)-based chiral stationary phase. J Chromatogr A 2020; 1630:461532. [PMID: 32950816 DOI: 10.1016/j.chroma.2020.461532] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/04/2020] [Accepted: 09/07/2020] [Indexed: 11/16/2022]
Abstract
An unusual convex-upward van Deemter curve was observed for the more retained enantiomer of a chiral sulfoxide (2-(benzylsulfinyl)benzamide) on a cellulose tris(4-chloro-3-methylphenylcarbamate)-based chiral stationary phase (CSP), prepared on silica particles of 1000 Å pore size. In contrast, the firstly eluted enantiomer of the same molecule exhibited the traditional convex-downward van Deemter curve. A detailed kinetic and thermodynamic investigation has revealed that this unusual phenomenon, which however has already been observed in chiral chromatography, originates when the adsorption of the compound is very strong and the solid-phase diffusion negligible. Experimentally, the intraparticle diffusion of the more retained enantiomer of the sulfoxide was found to be one order of magnitude smaller than that of the first eluted one. Overall, this translates into very little longitudinal diffusion (b-term of van Deemter curve) accompanied by high solid-liquid mass transfer resistance (c-term). Finally the comparison with another, differently-substituted chiral sulfoxide (whose enantiomers both exhibit traditional van Deemter curve behavior) has allowed to correlate these findings to the specific characteristics of the molecule.
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Affiliation(s)
- Simona Felletti
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, via L. Borsari 46, 44121 Ferrara, Italy
| | - Chiara De Luca
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, via L. Borsari 46, 44121 Ferrara, Italy
| | - Giulio Lievore
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, via L. Borsari 46, 44121 Ferrara, Italy
| | - Tatiana Chenet
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, via L. Borsari 46, 44121 Ferrara, Italy
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave., Torrance, CA 90501, United States
| | - Alberto Cavazzini
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, via L. Borsari 46, 44121 Ferrara, Italy.
| | - Martina Catani
- Department of Chemistry and Pharmaceutical Sciences, University of Ferrara, via L. Borsari 46, 44121 Ferrara, Italy.
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11
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Shedania Z, Kakava R, Volonterio A, Farkas T, Chankvetadze B. Separation of enantiomers of chiral sulfoxides in high-performance liquid chromatography with cellulose-based chiral selectors using acetonitrile and acetonitrile-water mixtures as mobile phases. J Chromatogr A 2020; 1609:460445. [DOI: 10.1016/j.chroma.2019.460445] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 08/03/2019] [Accepted: 08/08/2019] [Indexed: 10/26/2022]
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12
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Matarashvili I, Kobidze G, Chelidze A, Dolidze G, Beridze N, Jibuti G, Farkas T, Chankvetadze B. The effect of temperature on the separation of enantiomers with coated and covalently immobilized polysaccharide-based chiral stationary phases. J Chromatogr A 2019; 1599:172-179. [DOI: 10.1016/j.chroma.2019.04.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 04/06/2019] [Accepted: 04/10/2019] [Indexed: 11/26/2022]
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13
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Lipka E, Dascalu AE, Messara Y, Tsutsqiridze E, Farkas T, Chankvetadze B. Separation of enantiomers of native amino acids with polysaccharide-based chiral columns in supercritical fluid chromatography. J Chromatogr A 2019; 1585:207-212. [DOI: 10.1016/j.chroma.2018.11.049] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/14/2018] [Accepted: 11/20/2018] [Indexed: 11/15/2022]
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14
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Khundadze N, Pantsulaia S, Fanali C, Farkas T, Chankvetadze B. On our way to sub-second separations of enantiomers in high-performance liquid chromatography. J Chromatogr A 2018; 1572:37-43. [PMID: 30139619 DOI: 10.1016/j.chroma.2018.08.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 08/02/2018] [Accepted: 08/11/2018] [Indexed: 11/17/2022]
Abstract
In this study our preliminary attempt for obtaining fast and highly efficient separations of enantiomers in high-performance liquid chromatography with slightly modified state-of-the-art commercial instrumentation is described. In order to reach this goal after careful selection of chiral analytes, the preparation of chiral stationary phase (CSP), mobile phase composition and column dimensions were optimized. The concept of segmented chiral-achiral column was introduced. As the result of these optimizations baseline separation of enantiomers was achieved with the analysis time between 1-2 s.
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Affiliation(s)
- Nana Khundadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave. 3, 0179 Tbilisi, Georgia
| | - Salome Pantsulaia
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave. 3, 0179 Tbilisi, Georgia
| | - Chiara Fanali
- Department of Medicine, University Campus Bio-Medico of Rome, Via Alvaro del Portillo 21, 00128 Rome, Italy
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave., Torrance, 90501 CA, USA
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave. 3, 0179 Tbilisi, Georgia.
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15
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Bezhitashvili L, Bardavelidze A, Mskhiladze A, Gumustas M, Ozkan SA, Volonterio A, Farkas T, Chankvetadze B. Application of cellulose 3,5-dichlorophenylcarbamate covalently immobilized on superficially porous silica for the separation of enantiomers in high-performance liquid chromatography. J Chromatogr A 2018; 1571:132-139. [PMID: 30098733 DOI: 10.1016/j.chroma.2018.08.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [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: 06/11/2018] [Revised: 07/27/2018] [Accepted: 08/03/2018] [Indexed: 02/01/2023]
Abstract
Our earlier studies have demonstrated the applicability of polysaccharide-based chiral selectors in combination with superficially porous (or core-shell) silica (SPS) particles for the preparation of highly efficient chiral stationary phases (CSP). In earlier studies, CSPs were prepared by coating (adsorption) of the chiral selector onto the surface of silica. In this study we report for the first time the CSP obtained by covalent immobilization of a chiral selector onto the surface of SPS particles. The applicability of this CSP for the separation of enantiomers in pure methanol and acetonitrile, as well as in n-hexane/2-propanol mobile phases is shown. The effect of the injected sample amount, mobile phase flow rate and detection frequency on separation performance were studied, as well as high efficiency separation of enantiomers with the analysis time less than 30 s was attempted.
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Affiliation(s)
- Lia Bezhitashvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia
| | - Anna Bardavelidze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia
| | - Antonina Mskhiladze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia; Faculty of Natural Sciences and Healthcare, Sokhumi State University, Polytkovskaya 9, 0186 Tbilisi, Georgia
| | - Mehmet Gumustas
- Ankara University, Institute of Forensic Sciences, Department of Forensic Toxicology, Ankara, Turkey; Ankara University, Faculty of Pharmacy, Department of Analytical Chemistry, Anadolu Ave, 06100 Ankara, Turkey
| | - Sibel A Ozkan
- Ankara University, Faculty of Pharmacy, Department of Analytical Chemistry, Anadolu Ave, 06100 Ankara, Turkey
| | - Alessandro Volonterio
- Department of Chemistry, Materials and Chemical Engineering "G. Natta" Politecnico di Milano, Via Mancinelli 7-20131, Milano, Italy; C.N.R. Istituto di Chimica del Riconoscimento Molecolare (ICRM), Via Mancinelli 7, 20131 Milano, Italy
| | - Tivadar Farkas
- Phenomenex Inc., 411 Madrid Ave., Torrance, 90501 CA, USA
| | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences, Tbilisi State University, Chavchavadze Ave 3, 0179 Tbilisi, Georgia.
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16
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Khatiashvili T, Kakava R, Matarashvili I, Tabani H, Fanali C, Volonterio A, Farkas T, Chankvetadze B. Separation of enantiomers of selected chiral sulfoxides with cellulose tris(4-chloro-3-methylphenylcarbamate)-based chiral columns in high-performance liquid chromatography with very high separation factor. J Chromatogr A 2018; 1545:59-66. [DOI: 10.1016/j.chroma.2018.02.054] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 02/17/2018] [Accepted: 02/25/2018] [Indexed: 11/16/2022]
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17
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Beridze N, Tsutskiridze E, Takaishvili N, Farkas T, Chankvetadze B. Comparative Enantiomer-Resolving Ability of Coated and Covalently Immobilized Versions of Two Polysaccharide-Based Chiral Selectors in High-Performance Liquid Chromatography. Chromatographia 2018. [DOI: 10.1007/s10337-018-3493-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [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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18
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Abstract
Macroautophagy (autophagy) is a dynamic intracellular degradation pathway. Monitoring the flux through the autophagy pathway is experimentally challenging but obviously a prerequisite for the proper investigation of the process. Here, we present an indirect autophagy flux assay based on monitoring the degradation of an autophagosome-associated fusion protein Rluc-LC3 by luminescence detection. The method is suitable for screening purposes with a high number of parallel samples and can be used for measurements in cell lysates as well as in living cells. The Rluc-LC3 assay has proven useful for the identification of genes, miRNAs, and small molecules that regulate autophagy flux in mammalian cells.
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Affiliation(s)
- T Farkas
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark
| | - M Jäättelä
- Cell Death and Metabolism, Center for Autophagy, Recycling and Disease, Danish Cancer Society Research Center, Copenhagen, Denmark.
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19
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Demeter I, Nagy K, Farkas T, Kis Z, Kocsis K, Knapp L, Gellért L, Fülöp F, Vécsei L, Toldi J. ISDN2014_0251: REMOVED: Paradox effects of kynurenines on LTP induction. An in vivo study in the Wistar rat. Int J Dev Neurosci 2015. [DOI: 10.1016/j.ijdevneu.2015.04.206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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20
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Matarashvili I, Shvangiradze I, Chankvetadze L, Sidamonidze S, Takaishvili N, Farkas T, Chankvetadze B. High-performance liquid chromatographic separations of stereoisomers of chiral basic agrochemicals with polysaccharide-based chiral columns and polar organic mobile phases. J Sep Sci 2015; 38:4173-9. [DOI: 10.1002/jssc.201500919] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 09/27/2015] [Accepted: 10/03/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Iza Matarashvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | - Iamze Shvangiradze
- Department of Ecology and Environmental Protection, Faculty of Informatics, Mathematics and Natural Sciences; Georgian University of St. Andrew the Apostle; Tbilisi Georgia
| | - Lali Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | - Shota Sidamonidze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
- Department of Ecology and Environmental Protection, Faculty of Informatics, Mathematics and Natural Sciences; Georgian University of St. Andrew the Apostle; Tbilisi Georgia
| | - Nino Takaishvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | | | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
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21
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Simon J, Farkas T, Gingl Z, Csillik A, Korsós A, Rudas L, Zöllei É. Noninvasive continuous arterial pressure measurements in the assessment of acute, severe central hypovolemia. Acta Physiol Hung 2015; 102:43-50. [PMID: 25804388 DOI: 10.1556/aphysiol.102.2015.1.4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
UNLABELLED Acute, severe hypovolemia is a medical emergency. Traditional vital sign parameters allow no optimal triage. High predictive power of finger plethysmography-based stroke volume (SV) and pulse pressure (PP) was recently suggested. To assess the performance of the PP and SV parameters, lower body negative pressure of -40 mmHg, than -60 mmHg - corresponding to moderate and severe central hypovolemia - was applied in 22 healthy males (age 35 ± 7 years). Slow breathing induced fluctuations in the above indices, characterized by stroke volume variability (SVV), and pulse pressure variability (PPV), were assessed. Responses in heart rate (HR) and shock index (SI) were also studied. Discriminative capacity of these parameters was characterized by the area under the ROC (receiver operating characteristic) curves (AUC). RESULTS In comparison of baseline to severe central hypovolemia SV, PP, HR, and SI showed good discriminating capacity (AUC 99%, 88%, 87%, and 93%, respectively). The discriminating capacity of SVV and PPV was poor (77% and 70%, respectively). In comparison of moderate and severe hypovolemia, the discriminating capacity of the studied parameters was uniformly limited. CONCLUSIONS Plethysmography-based SV and PP parameters can be used to detect acute severe volume loss. Sensitive parameters discriminating moderate and severe central hypovolemia are still lacking.
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Affiliation(s)
- J Simon
- University of Szeged Department of Anesthesiology and Intensive Care, Faculty of Medicine Korányi fasor 7 H-6720 Szeged Hungary
| | - T Farkas
- University of Szeged Department of Anesthesiology and Intensive Care, Faculty of Medicine Korányi fasor 7 H-6720 Szeged Hungary
| | - Z Gingl
- University of Szeged Department of Technical Informatics Szeged Hungary
| | - A Csillik
- University of Szeged Department of Anesthesiology and Intensive Care, Faculty of Medicine Korányi fasor 7 H-6720 Szeged Hungary
| | - A Korsós
- University of Szeged Department of Anesthesiology and Intensive Care, Faculty of Medicine Korányi fasor 7 H-6720 Szeged Hungary
| | - László Rudas
- University of Szeged Department of Anesthesiology and Intensive Care, Faculty of Medicine Korányi fasor 7 H-6720 Szeged Hungary
| | - É Zöllei
- University of Szeged Department of Anesthesiology and Intensive Care, Faculty of Medicine Korányi fasor 7 H-6720 Szeged Hungary
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22
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Ma Y, Chassy AW, Miyazaki S, Motokawa M, Morisato K, Uzu H, Ohira M, Furuno M, Nakanishi K, Minakuchi H, Mriziq K, Farkas T, Fiehn O, Tanaka N. Efficiency of short, small-diameter columns for reversed-phase liquid chromatography under practical operating conditions. J Chromatogr A 2015; 1383:47-57. [DOI: 10.1016/j.chroma.2015.01.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 01/05/2015] [Accepted: 01/07/2015] [Indexed: 11/25/2022]
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23
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Gogaladze K, Chankvetadze L, Tsintsadze M, Farkas T, Chankvetadze B. Effect of Basic and Acidic Additives on the Separation of Some Basic Drug Enantiomers on Polysaccharide-Based Chiral Columns With Acetonitrile as Mobile Phase. Chirality 2015; 27:228-34. [DOI: 10.1002/chir.22417] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 10/16/2014] [Indexed: 01/26/2023]
Affiliation(s)
- Khatuna Gogaladze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | - Lali Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | - Maia Tsintsadze
- Faculty of Chemistry; Georgian Technical University; Tbilisi Georgia
| | | | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
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24
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Kocsis K, Knapp L, Mészáros J, Kis Z, Farkas T, Vécsei L, Toldi J. Acetyl-L-carnitine and oxaloacetate in post-treatment against LTP impairment in a rat ischemia model. An in vitro electrophysiological study. J Neural Transm (Vienna) 2014; 122:867-72. [PMID: 25432433 DOI: 10.1007/s00702-014-1343-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 11/22/2014] [Indexed: 12/31/2022]
Abstract
A high proportion of research relating to cerebral ischemia focuses on neuroprotection. The application of compounds normally present in the organism is popular, because they do not greatly influence the synaptic activity by receptor modulation, and can be administered without serious side effects. Oxaloacetate (OxAc) and acetyl-L-carnitine (ALC) are such favorable endogenous molecules. ALC can exert a protective effect by improving the energy state of the neurons under ischemic conditions. A promising neuroprotective strategy is glutamate scavenging, which can be achieved by the intravenous administration of OxAc. This study involved the possible protective effects of ALC and OxAc in different post-treatment protocols against long-term potentiation (LTP) impairment. Ischemia was induced in rats by 2-vessel occlusion, which led to a decreased LTP relative to the control group. High-dose (200 mg/kg) ALC or OxAc post-treatment resulted in a higher potentiation relative to the 2VO group, but it did not reach the control level, whereas low-dose ALC (100 mg/kg) in combination with OxAc completely restored the LTP function. Many previous studies have concluded that ALC can be protective only as pretreatment. The strategy described here reveals that ALC can also be neuroprotective when utilized as post-treatment against ischemia.
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Affiliation(s)
- K Kocsis
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, 6726, Szeged, Hungary
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25
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Knapp L, Gellért L, Kocsis K, Kis Z, Farkas T, Vécsei L, Toldi J. Neuroprotective effect of oxaloacetate in a focal brain ischemic model in the rat. Cell Mol Neurobiol 2014; 35:17-22. [PMID: 24807461 DOI: 10.1007/s10571-014-0064-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 04/16/2014] [Indexed: 11/26/2022]
Abstract
During an ischemic event, the well-regulated glutamate (Glu) homeostasis is disturbed, which gives rise to extremely high levels of this excitatory neurotransmitter in the brain tissues. It was earlier reported that the administration of oxaloacetate (OxAc) as a Glu scavenger reduces the Glu level in the brain by enhancing the brain-to-blood Glu efflux. Here, we studied the neuroprotective effect of OxAc administration in a new focal ischemic model in rats. Occlusion of the middle cerebral artery resulted in immediate reduction of the somatosensory-evoked responses (SERs), and the amplitudes remained at the reduced level throughout the whole ischemic period. On reperfusion, the SERs started to increase, but never reached the control level. OxAc proved to be protective, since the amplitudes started to recover even during the ischemia, and finally fully regained the control level. The findings of the histological measurements were in accordance with the electrophysiological data. After Fluoro Jade C staining, significantly fewer labeled cells were detected in the OxAc-treated group relative to the control. These results provide new evidence of the neuroprotective effect of OxAc against ischemic injury, which strengthens the likelihood of its future applicability as a novel neuroprotective agent for the treatment of ischemic stroke patients.
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Affiliation(s)
- L Knapp
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, Szeged, H-6726, Hungary
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26
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Gegenava M, Chankvetadze L, Farkas T, Chankvetadze B. Enantioseparation of selected chiral sulfoxides in high-performance liquid chromatography with polysaccharide-based chiral selectors in polar organic mobile phases with emphasis on enantiomer elution order. J Sep Sci 2014; 37:1083-8. [DOI: 10.1002/jssc.201301318] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2013] [Revised: 02/21/2014] [Accepted: 02/22/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Maia Gegenava
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences, Tbilisi State University; Tbilisi Georgia
| | - Lali Chankvetadze
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences, Tbilisi State University; Tbilisi Georgia
| | | | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences, Tbilisi State University; Tbilisi Georgia
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27
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Kocsis K, Knapp L, Gellért L, Oláh G, Kis Z, Takakuwa H, Iwamori N, Ono E, Toldi J, Farkas T. Acetyl-L-carnitine normalizes the impaired long-term potentiation and spine density in a rat model of global ischemia. Neuroscience 2014; 269:265-72. [PMID: 24704513 DOI: 10.1016/j.neuroscience.2014.03.055] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 02/28/2014] [Accepted: 03/26/2014] [Indexed: 02/02/2023]
Abstract
As a consequence of an ischemic episode, energy production is disturbed, leading to neuronal cell death. Despite intensive research, the quest for promising neuroprotective drugs has largely failed, not only because of ineffectiveness, but also because of serious side-effects and dosing difficulties. Acetyl-l-carnitine (ALC) is an essential nutrient which plays a key role in energy metabolism by transporting fatty acids into mitochondria for β-oxidation. It is an endogenous compound and can be used at high dose without toxicity in research into ischemia. Its neuroprotective properties have been reported in many studies, but its potential action on long-term potentiation (LTP) and dendritic spine density has not been described to date. The aim of the present study was an evaluation of the possible protective effect of ALC after ischemic insults inflicted on hippocampal synaptic plasticity in a 2-vessel occlusion (2VO) model in rats. For electrophysiological measurements, LTP was tested on hippocampal slices. The Golgi-Cox staining technique was used to determine spine density. 2VO resulted in a decreased, unstable LTP and a significant loss of dendritic spines. ALC administered after 2VO was not protective, but as pretreatment prior to 2VO it restored LTP nearly to the control level. This finding paralleled the histological analysis: ALC pretreatment resulted in the reappearance of dendritic spines on the CA1 pyramidal cells. Our data demonstrate that ALC administration can restore hippocampal function and spine density. ALC probably acts by enhancing the aerobic metabolic pathway, which is inhibited during and following ischemic attacks.
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Affiliation(s)
- K Kocsis
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary; MTA-SZTE Neuroscience Research Group, Szeged, Hungary
| | - L Knapp
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary
| | - L Gellért
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary; MTA-SZTE Neuroscience Research Group, Szeged, Hungary
| | - G Oláh
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary
| | - Zs Kis
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary
| | - H Takakuwa
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-Motoyama, Kita, Kyoto 603-8555, Japan
| | - N Iwamori
- Department of Biomedicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Center of Biomedical Research, Research Center for Human Disease Modeling, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - E Ono
- Department of Biomedicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan; Center of Biomedical Research, Research Center for Human Disease Modeling, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - J Toldi
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary; MTA-SZTE Neuroscience Research Group, Szeged, Hungary
| | - T Farkas
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary.
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28
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Sanchez AC, Friedlander G, Fekete S, Anspach J, Guillarme D, Chitty M, Farkas T. Pushing the performance limits of reversed-phase ultra high performance liquid chromatography with 1.3μm core–shell particles. J Chromatogr A 2013; 1311:90-7. [DOI: 10.1016/j.chroma.2013.08.065] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Revised: 08/04/2013] [Accepted: 08/18/2013] [Indexed: 10/26/2022]
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29
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Gellért L, Knapp L, Németh K, Herédi J, Varga D, Oláh G, Kocsis K, Menyhárt A, Kis Z, Farkas T, Vécsei L, Toldi J. Post-ischemic treatment with L-kynurenine sulfate exacerbates neuronal damage after transient middle cerebral artery occlusion. Neuroscience 2013; 247:95-101. [PMID: 23685169 DOI: 10.1016/j.neuroscience.2013.04.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [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: 03/03/2013] [Revised: 04/27/2013] [Accepted: 04/30/2013] [Indexed: 11/28/2022]
Abstract
Since brain ischemia is one of the leading causes of adult disability and death, neuroprotection of the ischemic brain is of particular importance. Acute neuroprotective strategies usually have the aim of suppressing glutamate excitotoxicity and an excessive N-methyl-d-aspartate (NMDA) receptor function. Clinically tolerated antagonists should antagonize an excessive NMDA receptor function without compromising the normal synaptic function. Kynurenic acid (KYNA) an endogenous metabolite of the tryptophan metabolism, may be an attractive neuroprotectant in this regard. The manipulation of brain KYNA levels was earlier found to effectively enhance the histopathological outcome of experimental ischemic/hypoxic states. The present investigation of the neuroprotective capacity of L-kynurenine sulfate (L-KYNs) administered systemically after reperfusion in a novel distal middle cerebral artery occlusion (dMCAO) model of focal ischemia/reperfusion revealed that in contrast with earlier results, treatment with L-KYNs worsened the histopathological outcome of dMCAO. This contradictory result indicates that post-ischemic treatment with L-KYNs may be harmful.
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Affiliation(s)
- L Gellért
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary
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Matarashvili I, Chankvetadze L, Fanali S, Farkas T, Chankvetadze B. HPLC separation of enantiomers of chiral arylpropionic acid derivatives using polysaccharide-based chiral columns and normal-phase eluents with emphasis on elution order. J Sep Sci 2013; 36:140-7. [DOI: 10.1002/jssc.201200885] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 10/10/2012] [Accepted: 10/10/2012] [Indexed: 11/10/2022]
Affiliation(s)
- Iza Matarashvili
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | - Lali Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
| | - Salvatore Fanali
- Institute of Chemical Methodologies; Consiglio Nazionale delle Ricerche; Monterotondo Scalo (Roma); Italy
| | | | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry, School of Exact and Natural Sciences; Tbilisi State University; Tbilisi Georgia
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31
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Rosca M, Popescu B, Beladan C, Calin A, Gurzun M, Avram A, Enache R, Coman I, Ginghina C, De Sousa CC, Goncalves A, Rangel I, Correia A, Macedo F, Maciel M, Debonnaire P, Thijssen J, Leong D, Joyce E, Bax J, Schalij M, Atsma D, Delgado V, Marsan N, Halmai L, Farkas T, Kalapos A, Domsik P, Sepp R, Forster T, Nemes A, Prinz C, Schwarz M, Ilic I, Laser K, Lehmann R, Vogt J, Van Buuren F, Bogunovic N, Horstkotte D, Faber L, Kim K, Kim Y, Lee S, Kim H, Sohn D, Schnell F, Donal E, Reynaud A, Ridard C, Mabo P, Carre F, Stolfo D, Merlo M, Pinamonti B, Barbati G, Di Lenarda A, Sinagra G, Jurado Roman A, Montero Cabezas J, De Dios Perez S, Garcia Tejada J, Velazquez Martin M, Hernandez Hernandez F, Gonzalez-Trevilla AA, Andreu Dussac J, Tascon Perez J, Montero Cabezas J, Jurado Roman A, De Riva Silva M, Velazquez Martin M, Garcia Tejada J, Hernandez Hernandez F, Albarran Gonzalez-Trevilla A, Andreu Dussac J, Coma Sanmartin R, Tascon Perez J. Hypertrophic cardiomyopathy: function and outcome. Eur Heart J Cardiovasc Imaging 2012. [DOI: 10.1093/ehjci/jes265] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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32
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Fuzik J, Gellért L, Oláh G, Herédi J, Kocsis K, Knapp L, Nagy D, Kincses ZT, Kis Z, Farkas T, Toldi J. Fundamental interstrain differences in cortical activity between Wistar and Sprague-Dawley rats during global ischemia. Neuroscience 2012; 228:371-81. [PMID: 23103797 DOI: 10.1016/j.neuroscience.2012.10.042] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Revised: 10/18/2012] [Accepted: 10/19/2012] [Indexed: 10/27/2022]
Abstract
Four-vessel occlusion (4VO), a frequently used model of global cerebral ischemia in rats, results in a dysfunction in wide brain areas, including the cerebral cortex and hippocampus. However, there are pronounced differences in response to global ischemia between the laboratory rat strains used in these studies. In the present work, the immediate acute effects of 4VO-induced global ischemia on the spontaneous electrocorticogram (ECoG) signals were analyzed in Wistar and Sprague-Dawley rats. The ECoG was isoelectric during the 10 min of global cerebral ischemia in Wistar rats and the first burst (FB) was seen 10-13 min after the start of reperfusion. In Sprague-Dawley rats, the FB was detected immediately after the start of 4VO or a few seconds later. The burst suppression ratio (BSR) in Wistar rats decreased to 45% in 5 min after FB, and after 25 min it was approximately 40%. In Sprague-Dawley rats, the BSR was 55% immediately after the FB and it decreased steeply to reach 0% by 10 min. There was also a significant difference between the two strains in the frequency composition of the ECoG pattern. The power spectral densities of the two strains differed virtually throughout the post-ischemic state. The histological results (Evans Blue, Cresyl Violet and Fluoro Jade C stainings) supplemented the electrophysiological data: the neuronal damage in the CA1 pyramids in Wistar rats was severe, whereas in the Sprague-Dawley animals it was only partial. These observations clearly demonstrate that the use of different rat strains (e.g. Wistar vs. Sprague-Dawley) can be a source of considerable variability in the results of acute experiments on global ischemia and it is important that the laboratory rats used in such experiments should be carefully chosen.
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Affiliation(s)
- J Fuzik
- University of Szeged, Department of Physiology, Anatomy and Neuroscience, Közép fasor 52, H-6726 Szeged, Hungary
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Jibuti G, Mskhiladze A, Takaishvili N, Karchkhadze M, Chankvetadze L, Farkas T, Chankvetadze B. HPLC separation of dihydropyridine derivatives enantiomers with emphasis on elution order using polysaccharide-based chiral columns. J Sep Sci 2012; 35:2529-37. [DOI: 10.1002/jssc.201200443] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 06/04/2012] [Accepted: 06/04/2012] [Indexed: 11/08/2022]
Affiliation(s)
- George Jibuti
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences; Tbilisi State University; Tbilisi; Georgia
| | - Antonina Mskhiladze
- Faculty of Natural Sciences and Healthcare; Sokhumi State University; Tbilisi; Georgia
| | - Nino Takaishvili
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences; Tbilisi State University; Tbilisi; Georgia
| | - Marina Karchkhadze
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences; Tbilisi State University; Tbilisi; Georgia
| | - Lali Chankvetadze
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences; Tbilisi State University; Tbilisi; Georgia
| | | | - Bezhan Chankvetadze
- Institute of Physical and Analytical Chemistry; School of Exact and Natural Sciences; Tbilisi State University; Tbilisi; Georgia
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Premasuthan A, Ng J, Kanthaswamy S, Trask JS, Houghton P, Farkas T, Sestak K, Smith DG. Molecular ABO phenotyping in cynomolgus macaques using real-time quantitative PCR. ACTA ACUST UNITED AC 2012; 80:363-7. [PMID: 22861170 DOI: 10.1111/j.1399-0039.2012.01935.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 06/20/2012] [Accepted: 07/02/2012] [Indexed: 12/14/2022]
Abstract
Macaques are commonly used in biomedical research as animal models of human disease. The ABO phenotype of donors and recipients plays an important role in the success of transplantation and stem cell research of both human and macaque tissue. Traditional serological methods for ABO phenotyping can be time consuming, provide ambiguous results and/or require tissue that is unavailable or unsuitable. We developed a novel method to detect the A, B, and AB phenotypes of macaques using real-time quantitative polymerase chain reaction. This method enables the simple and rapid screening of these phenotypes in macaques without the need for fresh blood or saliva. This study reports the distribution of the A, B, and AB phenotypes of captive cynomolgus macaques that, while regionally variable, closely resembles that of rhesus macaques. Blood group B, as in rhesus macaques, predominates in cynomolgus macaques and its frequency distribution leads to a probability of major incompatibility of 41%. No silencing mutations have been identified in exon 6 or 7 in macaques that could be responsible for the O phenotype, that, although rare, have been reported. The excess homozygosity of rhesus and cynomolgus macaque genotypes in this study, that assumes the absence of the O allele, suggests the possibility of some mechanism preventing the expression of the A and B transferases.
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Affiliation(s)
- A Premasuthan
- Molecular Anthropology Laboratory, University of California, Davis, CA 95616, USA
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Lomsadze K, Jibuti G, Farkas T, Chankvetadze B. Comparative high-performance liquid chromatography enantioseparations on polysaccharide based chiral stationary phases prepared by coating totally porous and core–shell silica particles. J Chromatogr A 2012; 1234:50-5. [DOI: 10.1016/j.chroma.2012.01.084] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 01/24/2012] [Accepted: 01/28/2012] [Indexed: 11/15/2022]
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Sanchez AC, Anspach JA, Farkas T. Performance optimizing injection sequence for minimizing injection band broadening contributions in high efficiency liquid chromatographic separations. J Chromatogr A 2012; 1228:338-48. [DOI: 10.1016/j.chroma.2012.01.038] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 01/13/2012] [Accepted: 01/16/2012] [Indexed: 11/30/2022]
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37
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Nagy K, Plangár I, Tuka B, Gellért L, Varga D, Demeter I, Farkas T, Kis Z, Marosi M, Zádori D, Klivényi P, Fülöp F, Szatmári I, Vécsei L, Toldi J. Synthesis and biological effects of some kynurenic acid analogs. Bioorg Med Chem 2011; 19:7590-6. [PMID: 22079867 DOI: 10.1016/j.bmc.2011.10.029] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Accepted: 10/10/2011] [Indexed: 10/16/2022]
Abstract
The overactivation of excitatory amino acid receptors plays a key role in the pathomechanism of several neurodegenerative disorders and in ischemic and post-ischemic events. Kynurenic acid (KYNA) is an endogenous product of the tryptophan metabolism and, as a broad-spectrum antagonist of excitatory amino acid receptors, may serve as a protective agent in neurological disorders. The use of KYNA is excluded, however, because it hardly crosses the blood-brain barrier. Accordingly, new KYNA analogs which can readily cross this barrier and exert their complex anti-excitatory activity are generally needed. During the past 6 years, we have developed several KYNA derivatives, among others KYNA amides. These new analogs included one, N-(2-N,N-dimethylaminoethyl)-4-oxo-1H-quinoline-2-carboxamide hydrochloride (KYNA-1), that has proved to be neuroprotective in several models. This paper reports on the synthesis of 10 new KYNA amides (KYNA-1-KYNA-10) and on the effectiveness of these molecules as inhibitors of excitatory synaptic transmission in the CA1 region of the hippocampus. The molecular structure and functional effects of KYNA-1 are compared with those of other KYNA amides. Behavioral studies with these KYNA amides demonstrated that they do not exert significant nonspecific general side-effects. KYNA-1 may therefore be considered a promising candidate for clinical studies.
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Affiliation(s)
- K Nagy
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary
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Gritti F, Farkas T, Heng J, Guiochon G. On the relationship between band broadening and the particle-size distribution of the packing material in liquid chromatography: theory and practice. J Chromatogr A 2011; 1218:8209-21. [PMID: 21993511 DOI: 10.1016/j.chroma.2011.09.034] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 09/11/2011] [Accepted: 09/13/2011] [Indexed: 11/24/2022]
Abstract
The influence of the particle size distribution (PSD) on the band broadening and the efficiency of packed columns is investigated on both theoretical and practical viewpoints. Each of the classical contributions to mass transfer kinetics, those due to longitudinal diffusion, eddy dispersion, and solid-liquid mass transfer resistance are measured and analyzed in terms of their expected and observed intensity as a function of the PSD of mixtures of the commercially available packing materials, 5 and 3 μm Luna-C₁₈ particles (Phenomenex, Torrance, CA, USA). Six 4.6 mm × 150 mm columns were packed with different mixtures of these two materials. The efficiencies of these columns were measured for a non-retained and a retained analytes in a mixture of acetonitrile and water. The longitudinal diffusion coefficient was directly measured by the peak parking method. The solid-liquid mass transfer coefficient was measured from the combination of the peak parking method, the best model of effective diffusion coefficient and the actual PSDs of the different particle mixtures measured by Coulter counter experiments. The eddy diffusion term was measured according to a recently developed protocol, by numerical integration of the peak profiles. Our results clearly show that the PSD has no measurable impact on any of the coefficients of the van Deemter equation. On the contrary and surprisingly, adding a small fraction of large particles to a batch of small particles can improve the quality of the packing of the fine particles. Our results indirectly confirm that the success of sub-3 μm shell particles is due to the roughness of their external surface, which contributes to eliminate most of the nefarious wall effects.
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Affiliation(s)
- Fabrice Gritti
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996-1600, USA
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39
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Chankvetadze L, Ghibradze N, Karchkhadze M, Peng L, Farkas T, Chankvetadze B. Enantiomer elution order reversal of fluorenylmethoxycarbonyl-isoleucine in high-performance liquid chromatography by changing the mobile phase temperature and composition. J Chromatogr A 2011; 1218:6554-60. [DOI: 10.1016/j.chroma.2011.06.068] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Revised: 06/15/2011] [Accepted: 06/16/2011] [Indexed: 10/18/2022]
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Damjanova I, Jakab M, Farkas T, Mészáros J, Galántai Z, Turcsányi I, Bistyák A, Juhász A, Pászti J, Kiss I, Kardos G. From farm to fork follow-up of thermotolerant campylobacters throughout the broiler production chain and in human cases in a Hungarian county during a ten-months period. Int J Food Microbiol 2011; 150:95-102. [PMID: 21864930 DOI: 10.1016/j.ijfoodmicro.2011.07.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 05/05/2011] [Accepted: 07/09/2011] [Indexed: 11/19/2022]
Abstract
A study tracking thermotolerant campylobacters from the setting of the broilers throughout the whole rearing period, slaughter and sale of chicken products in five consecutive broiler rotations of the same henhouse as well as in two different other farms was conducted in a well-defined geographic area (Hajdú-Bihar county, Hungary) between March 2006 and Feb 2007. All notified cases of human campylobacteriosis in this area during the study period were also included. One hundred and one, 44, 23 and 282 Campylobacter jejuni and 13, 15, 20 and 60C. coli were isolated from broiler houses, slaughterhouses, retail shops and human samples, respectively. Sixty-two isolates collected from broilers or their environment selected from different flocks (57C. jejuni, 5C. coli), 92 isolates collected from abattoirs and retail shops (72C. jejuni, 20C. coli), as well as 85 randomly selected human isolates (74C. jejuni, 11C. coli) were subjected to PFGE analysis using restriction enzymes KpnI and SmaI. Sixty-six of the isolates produced unique Sma-Kpn profiles; the majority (46) of these were of human origin. The remaining isolates formed PFGE clusters of between 2-25 isolates with 14 (12C. jejuni and 2C. coli) main clusters comprised of five or more isolates with identical KpnI-SmaI patterns. Two genetic clones of C. jejuni (clone A, n=25; clone B, n=20) included 18% of isolates from different sources. Generally, isolates from one cluster were found in 1-3 different flocks, notably, clone B was present in three rotations including those from the two independent farms. Six of the seven investigated flocks had one or two characteristic prevalent clones. Transmission of clones between consecutive flocks was frequently seen. Spread of both C. jejuni and C. coli was traced multiple times along the food chain; eight C. jejuni, but no C. coli clones were detected both in broilers and humans. These data suggest that broilers were the major source for C. jejuni but not for C. coli in the studied area and period. For C. jejuni the carryover of strains between consecutive flocks may be a common event, but the strain is eventually replaced by another and consecutive carryover events seem to be infrequent. The majority of the human disease was due to nonepidemic strains; some clones were transmitted from more than one broiler flocks (including epidemiologically unrelated flocks) to humans multiple times.
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Affiliation(s)
- I Damjanova
- National Center for Epidemiology, H-1097 Budapest, Gyáli út 2-6., Hungary
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Peng L, Jayapalan S, Chankvetadze B, Farkas T. Reversed-phase chiral HPLC and LC/MS analysis with tris(chloromethylphenylcarbamate) derivatives of cellulose and amylose as chiral stationary phases. J Chromatogr A 2010; 1217:6942-55. [DOI: 10.1016/j.chroma.2010.08.075] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 08/24/2010] [Accepted: 08/26/2010] [Indexed: 11/29/2022]
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42
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Fodor E, Szallas E, Kiss Z, Fodor A, Horvath LI, Chitwood DJ, Farkas T. Composition and Biophysical Properties of Lipids in Xenorhabdus nematophilus and Photorhabdus luminescens, Symbiotic Bacteria Associated with Entomopathogenic Nematodes. Appl Environ Microbiol 2010; 63:2826-31. [PMID: 16535651 PMCID: PMC1389206 DOI: 10.1128/aem.63.7.2826-2831.1997] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Primary and secondary forms of Photorhabdus luminescens Hm and Xenorhabdus nematophilus N2-4 were grown at 18 and 28(deg)C for 24 to 96 h, and we made determinations of the fatty-acid compositions of total lipids and of the fluidity measured by 5-doxyl-stearic acid embedded in liposomes made from total lipids. The levels of the unsaturated fatty acids 16:1 and 18:1 (those with chain lengths of 16 or 18 and one double bond) generally were higher in primary-phase variants of P. luminescens grown at 18(deg)C than in those grown at 28(deg)C. Prolonged culture at 18(deg)C caused the level of 18:1 to fall and reach that observed at 28(deg)C. The ratio of saturated to unsaturated fatty acids rose with prolonged culture times in variants of each species at both phases. When grown at 18(deg)C, the proportion of 16:1 in X. nematophilus was lower than in P. luminescens; the patterns of temperature-induced changes were similar in these species. X. nematophilus contained a greater percentage of short-chain fatty acids (i.e., with chain lengths of <14.0) than P. luminescens. Lipid liposomes from primary and secondary cultures of both bacterial species grown at 18(deg)C were more ordered (i.e., less fluid) than those grown at 28(deg)C. This result suggests the surprising absence of homeoviscous adaptation of membranes to temperature. Also, liposomes from primary cultures were more ordered than those from secondary cultures and membranes from primary cultures of P. luminescens were more ordered at both culture temperatures than membranes from X. nematophilus. The biological significance of the effect of growth conditions on membrane biophysical properties in these bacteria is discussed.
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De Paoli G, Lewis Sr. SA, Schuette EL, Lewis LA, Connatser RM, Farkas T. Photo- and Thermal-Degradation Studies of Select Eccrine Fingerprint Constituents. J Forensic Sci 2010; 55:962-9. [DOI: 10.1111/j.1556-4029.2010.01420.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Czuczai B, Farkas T, Rev E, Lelkes Z. New Mixed Integer Linear Programming Model for Solving Scheduling Problems with Special Characteristics. Ind Eng Chem Res 2009. [DOI: 10.1021/ie800124g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Barbara Czuczai
- Department of Chemical and Environmental Process Engineering, Budapest University of Technology and Economics, H-1111, Budapest, Budafoki ut 8. Hungary, and HAS-BUTE Materials Structure and Modeling Research Group
| | - Tivadar Farkas
- Department of Chemical and Environmental Process Engineering, Budapest University of Technology and Economics, H-1111, Budapest, Budafoki ut 8. Hungary, and HAS-BUTE Materials Structure and Modeling Research Group
| | - Endre Rev
- Department of Chemical and Environmental Process Engineering, Budapest University of Technology and Economics, H-1111, Budapest, Budafoki ut 8. Hungary, and HAS-BUTE Materials Structure and Modeling Research Group
| | - Zoltan Lelkes
- Department of Chemical and Environmental Process Engineering, Budapest University of Technology and Economics, H-1111, Budapest, Budafoki ut 8. Hungary, and HAS-BUTE Materials Structure and Modeling Research Group
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45
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Czuczai B, Farkas T, Rev E, Lelkes Z. Rolling Operation Algorithm for Solving Complex Scheduling Problems. Ind Eng Chem Res 2009. [DOI: 10.1021/ie801037k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Barbara Czuczai
- Department of Chemical and Environmental Process Engineering, H-1111, Budapest University of Technology and Economics, Budapest, Budafoki ut 8, Hungary, and HAS-BUTE Materials Structure and Modeling Research Group, Department of Chemical Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
| | - Tivadar Farkas
- Department of Chemical and Environmental Process Engineering, H-1111, Budapest University of Technology and Economics, Budapest, Budafoki ut 8, Hungary, and HAS-BUTE Materials Structure and Modeling Research Group, Department of Chemical Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
| | - Endre Rev
- Department of Chemical and Environmental Process Engineering, H-1111, Budapest University of Technology and Economics, Budapest, Budafoki ut 8, Hungary, and HAS-BUTE Materials Structure and Modeling Research Group, Department of Chemical Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
| | - Zoltan Lelkes
- Department of Chemical and Environmental Process Engineering, H-1111, Budapest University of Technology and Economics, Budapest, Budafoki ut 8, Hungary, and HAS-BUTE Materials Structure and Modeling Research Group, Department of Chemical Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
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46
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Dobos-Kovacs M, Varga I, Bekesi L, Dren CN, Nemeth I, Farkas T. Concurrent cryptosporidiosis and chicken anaemia virus infection in broiler chickens. Avian Pathol 2009; 23:365-8. [PMID: 18671102 DOI: 10.1080/03079459408419005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Concurrent infection with Cryptosporidium baileyi and chicken anaemia virus (CAV) was observed in a flock of 8000 4-week-old broiler chickens. The birds, showing overt symptoms of stunted growth and 25% mortality from hatching to 4 weeks of age, harboured the protozoan in the epithelial cells of the bursa of Fabricius and the urodeal portion of the cloaca. This is the first report on an outbreak of avian cryptosporidiosis associated with CAV.
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Affiliation(s)
- M Dobos-Kovacs
- Department of Pathology, University of Veterinary Science, Budapest, Hungary
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47
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Farkas T, Czuczai B, Rev E, Lelkes Z. New MINLP Model and Modified Outer Approximation Algorithm for Distillation Column Synthesis. Ind Eng Chem Res 2008. [DOI: 10.1021/ie0711426] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tivadar Farkas
- HAS-BUTE Materials Structure and Modeling Research Group, Department of Chemical Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
| | - Barbara Czuczai
- HAS-BUTE Materials Structure and Modeling Research Group, Department of Chemical Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
| | - Endre Rev
- HAS-BUTE Materials Structure and Modeling Research Group, Department of Chemical Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
| | - Zoltan Lelkes
- HAS-BUTE Materials Structure and Modeling Research Group, Department of Chemical Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Hungary
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Peng L, Farkas T. Analysis of basic compounds by reversed-phase liquid chromatography–electrospray mass spectrometry in high-pH mobile phases. J Chromatogr A 2008; 1179:131-44. [DOI: 10.1016/j.chroma.2007.11.048] [Citation(s) in RCA: 64] [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: 08/06/2007] [Revised: 10/27/2007] [Accepted: 11/13/2007] [Indexed: 10/22/2022]
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Abstract
AIMS We developed, optimized and tested two novel PCR assays specific for Salmonella enterica subspecies enterica serovar Infantis. METHODS AND RESULTS The fljB gene was chosen as the target sequence. Primers were designed on a consensus sequence built by sequencing the fljB gene of five genetically unrelated Hungarian S. Infantis strains and using sequence data from the GenBank (http://www.ncbi.nih.gov). Two alternative assays were designed, which share the reverse primer. Both proved to be highly specific to S. Infantis, neither reacted with 42 other nontyphoidal serovariants tested. The detection limit of the assays was determined to be 10(5) CFU ml(-1) from pure culture, and 10(6) CFU g(-1) from artificially spiked chicken faeces samples. CONCLUSIONS Although the detection limit is rather high to allow for using them for direct detection, the assays may be useful in identification of S. Infantis both for diagnostic and for research purposes. SIGNIFICANCE AND IMPACT OF THE STUDY The described PCR assays allow for the correct identification of S. Infantis even when traditional serotyping methods fail because lack of expression of flagellar antigens.
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Affiliation(s)
- G Kardos
- Department of Microbiology, Central Agricultural Office, Veterinary Diagnostic Directorate, Debrecen, Hungary.
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50
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Farkas T, Maeda K, Sugiura H, Kai K, Hirai K, Otsuki K, Hayashi T. A serological survey of chickens, Japanese quail, pigeons, ducks and crows for antibodies to chicken anaemia virus (CAV) in Japan. Avian Pathol 2007; 27:316-20. [DOI: 10.1080/03079459808419344] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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