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Sample records for allison ms fache

  1. BauFach 2003 - kvaliteet ja uued lahendused / Sander Kingsepp

    Index Scriptorium Estoniae

    Kingsepp, Sander

    2003-01-01

    6.-9. XI 2003. a. Leipzigis toimunud ehituserialamessist BauFach 2003. Eesti oli esindatud puit- ja elementmajade (Astel AS, Eimur OÜ, Ritsu AS), saunade (Astel AS, Saunax OÜ) ning eeltöödeldud põranda- ja voodrilaudadega (Rait AS)

  2. Ghost signals in Allison emittance scanners

    International Nuclear Information System (INIS)

    Stockli, Martin P.; Leitner, M.; Moehs, D.P.; Keller, R.; Welton, R.F.

    2004-01-01

    For over 20 years, Allison scanners have been used to measure emittances of low-energy ion beams. We show that scanning large trajectory angles produces ghost signals caused by the sampled beamlet impacting on an electric deflection plate. The ghost signal strength is proportional to the amount of beam entering the scanner. Depending on the ions, and their velocity, the ghost signals can have the opposite or the same polarity as the main beam signals. The ghost signals cause significant errors in the emittance estimates because they appear at large trajectory angles. These ghost signals often go undetected because they partly overlap with the real signals, are mostly below the 1% level, and often hide in the noise. A simple deflection plate modification is shown to reduce the ghost signal strength by over 99%

  3. Ghost Signals In Allison Emittance Scanners

    International Nuclear Information System (INIS)

    Stockli, Martin P.; Leitner, M.; Keller, R.; Moehs, D.P.; Welton, R. F.

    2005-01-01

    For over 20 years, Allison scanners have been used to measure emittances of low-energy ion beams. We show that scanning large trajectory angles produces ghost signals caused by the sampled beamlet impacting on an electric deflection plate. The ghost signal strength is proportional to the amount of beam entering the scanner. Depending on the ions, and their velocity, the ghost signals can have the opposite or the same polarity as the main beam signals. The ghost signals cause significant errors in the emittance estimates because they appear at large trajectory angles. These ghost signals often go undetected because they partly overlap with the real signals, are mostly below the 1% level, and often hide in the noise. A simple deflection plate modification is shown to reduce the ghost signal strength by over 99%

  4. Aktuelle Tendenzen im computerunterstützten (Fach- Fremdsprachenunterricht

    Directory of Open Access Journals (Sweden)

    Pawel Szerszeń

    2015-03-01

    Full Text Available Die heutigen Entwicklungen im Bereich der Kommunikations-und Informationstechnologien tragen u.a. dazu bei,dass wir immer wieder mit neuen E-Learning-Angeboten im (Fach-Fremdsprachenunterricht konfrontiert werden. Diese Tatsa-che stellt u.a. die FremdsprachendidaktikerInnen vor neue Herausforderungen, für die eine kritische Reflexion über die didakti-sche Effizienz von E-Learning-Produkten Vorrang hat. Für eine solche didaktische Reflexion muss jedoch zunächst geklärt wer-den, welche Haupttypen von E-Learning-Produkten bestehen. Das Hauptziel des vorliegenden Beitrags ist somit der Versuch, diezurzeit bestehenden Haupttypen zu erfassen, zu kategorisieren sowie mit einigen Beispielen zu veranschaulichen wie auch aufinteressante Features ausgewählter Lernplattformen/Lernprogramme und auf einige neue E-Learning-Tendenzen hinzuweisen.Dieser Überblick stellt eine nötige und geeignete Grundlage für eine zukünftig mögliche Effizienzreflexion und-diskussion vordem Hintergrund möglicher Produktvergleiche dar

  5. Interkulturelle kommunikative Kompetenz – ein Versuch der Operationalisierung aus dem Fach Deutsch an der dänischen Lehrerausbildung

    DEFF Research Database (Denmark)

    Bjerre, Kirsten; Daryai-Hansen, Petra

    2017-01-01

    Mit diesem Artikel versuchen wir, den Begriff 'interkulturelle kommunikative Kompetenz‘ theoretisch zu entwickeln. Wir gehen zunächst der Frage nach, warum im Fach Deutsch als Fremdsprache mit interkultureller kommunikativer Kompetenz gearbeitet werden sollte und welche Herausforderungen sich...... hierbei stellen. Im Anschluss präsentieren wir unser Modell der interkulturellen kommunikativen Kompetenz, das wir für das Fach Deutsch ain der dänischen Lehrerausbildung auf der Grundlage eines Modells von Michael Byram aus dem Jahre 1997 entwickelt haben. Byrams Modell der interkulturellen...... zunächst die Begriffe ‚Kompetenz‘, ‚Kultur‘, ‚kommunikative Kompetenz‘ und ‚interkulturelle Kompetenz‘. Wir konkretisieren die Dimensionen des Modells im Anschluss anhand eines Unterrichtsbeispiels für das Fach Deutsch an der dänischen Einheitsschule („Folkeskole“). Abschließend skizzieren wir, wie unser...

  6. The FachRef-Assistant: Personalised, subject specific, and transparent stock management

    Directory of Open Access Journals (Sweden)

    Eike T. Spielberg

    2017-07-01

    Full Text Available We present in this paper a personalized web application for the weeding of printed resources: the FachRef-Assistant. It offers an extensive range of tools for evidence based stock management, based on the thorough analysis of usage statistics. Special attention is paid to the criteria individualization, transparency of the parameters used, and generic functions. Currently, it is designed to work with the Aleph-System from ExLibris, but efforts were spent to keep the application as generic as possible. For example, all procedures specific to the local library system have been collected in one Java package. The inclusion of library specific properties such as collections and systematics has been designed to be highly generic as well by mapping the individual entries onto an in-memory database. Hence simple adaption of the package and the mappings would render the FachRef-Assistant compatible to other library systems. The personalization of the application allows for the inclusion of subject specific usage properties as well as of variations between different collections within one subject area. The parameter sets used to analyse the stock and to prepare weeding and purchase proposal lists are included in the output XML-files to facilitate a high degree of transparency, objectivity and reproducibility.

  7. Laterale 10-fach-Biopsie der Prostata liefert bei Karzinomverdacht überlegene Detektionsraten

    Directory of Open Access Journals (Sweden)

    von Knobloch R

    2012-01-01

    Full Text Available Einleitung:Die Sextantenbiopsie der Prostata ist für eine verlässliche Karzinomdiagnostik nicht ausreichend. Vielerorts werden bereits bei der Erstbiopsie 12 Stanzen entnommen. In einer großen Serie von 10-fach-Biopsien unter bilateraler lokaler Leitungsanästhesie, wie bereits 2002 publiziert [1], überprüften wir die Qualität unserer Technik als Standard für die Erstbiopsie. Methode:Zwischen April 2005 und Dezember 2007 führten wir bei 736 Männern (Durchschnittsalter 67,5 ± 8,39 Jahre die Erstbiopsie der Prostata durch. Indikation für die Biopsie war entweder ein erhöhter PSA-Wert oder ein auffälliger Tastbefund. Bei allen Männern erfolgte die Biopsie der Prostata unter bilateraler lokaler Leitungsanästhesie. Es wurden nur Proben aus der peripheren Zone der Prostata unter transrektaler Ultraschallkontrolle entnommen. Ergebnisse:Durch die Biopsie wurde in 372 von 736 Fällen (50,5 % ein Karzinom identifiziert. Die Karzinomdetektionsrate war proportional zum PSA-Wert und indirekt proportional zum Organvolumen. Es zeigte sich eine eindeutige Korrelation zwischen der Anzahl positiver Stanzen bei der Biopsie mit dem pathologischen Stadium des Prostatektomiepräparates. 12 Männer (1,6 % mussten wegen akuter Prostatitis und 5 (0,7 % wegen rektaler Blutung wieder ins Krankenhaus eingewiesen werden. Von den 182 Patienten des Untersuchers R. v. K. wurde der durchschnittliche Schmerz der Biopsie mit 1,69 von maximal 10 angegeben. Die Detektions- und Komplikationsraten dieser Biopsietechnik unterschieden sich nicht nach Durchführung von Assistenz- oder Fachärzten. Schlussfolgerung: Die präsentierte Biopsietechnik liefert mit nur 10 Stanzen eine überlegene Detektionsrate und eine geringe Rate an Komplikationen. Sie sollte als Basis für die Definition eines Standards für die Erstbiopsie der Prostata bei Karzinomverdacht dienen.

  8. Medical specialist attendance in nursing homes [Beschreibung und Bewertung der fachärztlichen Versorgung von Pflegeheimbewohnern in Deutschland

    Directory of Open Access Journals (Sweden)

    Balzer, Katrin

    2013-04-01

    Full Text Available [english] The care in nursing homes was examined based on scientific studies. The analysis focuses on dementia and type II diabetes. There is evidence for deficits in the supply of medical specialist attendance to nursing home residents with these diseases in Germany. Compared with corresponding guidelines the medical care for nursing home residents may be too low or inadequate.[german] Es wird die Versorgung in Pflegeheimen auf Basis wissenschaftlicher Studien untersucht. Schwerpunkte der Analyse sind Demenz und Diabetes. Es gibt Hinweise auf fachärztliche Versorgungsmängel bei Pflegeheimbewohnern mit diesen Krankheiten in Deutschland. Verglichen mit entsprechenden Leitlinien bestehen mögliche Unter- bzw. Fehlversorgungen.

  9. TELEMED – Teaching Legal Medicine: Neukonzeption der Lehre im Fach Rechtsmedizin an der Universität des Saarlandes

    Directory of Open Access Journals (Sweden)

    Feiser, Judith

    2009-02-01

    Full Text Available Das Fach Rechtsmedizin ist Bestandteil der klinischen Lehre des Medizinstudiums. Im Zuge der Neuorientierung der medizinischen Ausbildung durch die Einführung der neuen ärztlichen Approbationsordnung wurde die Lehre am Institut für Rechtsmedizin der Universität des Saarlandes umstrukturiert. Dazu wurde das Lehrkonzept „TELEMED- Teaching Legal Medicine“ entwickelt, bestehend aus eLearning und Kleingruppenunterricht. Im Besonderen wurde bei der Gestaltung des neuen Lehrkonzeptes Wert darauf gelegt, die Lehre praxisbezogen zu gestalten. Aus diesem Anlass wurde am Ende des Wintersemesters (WS 2007/08 eine Evaluation mittels Fragebogen durchgeführt. An der Evaluation nahmen insgesamt 84 Studierende teil. Da das neue Lehrkonzept erstmals im WS 2007/08 Anwendung fand, konnte nicht mit früheren Semestern verglichen werden. Jedoch zeigten die Ergebnisse der Evaluation im Gesamten eine hohe Akzeptanz und positive Einschätzung des Konzeptes bei den Studierenden. Ferner ließ sich feststellen, dass die Verwendung von eLearning im Fach Rechtsmedizin einen großen Beitrag zur Umsetzung der praxisorientierten Lehre liefert.

  10. Rapid assessment of household needs in the Houston area after Tropical Storm Allison.

    Science.gov (United States)

    Waring, Stephen C; Reynolds, Kaye M; D'Souza, Gypsyamber; Arafat, Raouf R

    2002-09-01

    Tropical Storm Allison, which hit landfall near Galveston, Texas, on June 5, 2001, caused the most severe flood-related damage ever recorded in the Houston metropolitan area. The main goal of the public health response to tropical storm Allison was to evaluate the immediate health needs of the community. To estimate damage and household needs, we conducted a rapid needs assessment in the areas most affected by flooding with use of a modified cluster sampling method facilitated by Geographical Information Systems methodology. A total of 420 households participated in the survey, 210 each from the 2 sampling areas. We found a 4-fold increase in illness among persons living in flooded homes compared with those living in nonflooded homes. These findings suggest a need for rapid resolution of flood-related damage and the possibility that residents should seek temporary housing during clean-up and repair. In addition, we obtained reliable estimates of damage and household needs to help guide relief efforts. The findings underscore the usefulness of a rapid-needs assessment as a tool to identify actual health threats and to facilitate delivery of resources to those with the greatest and most immediate need.

  11. The Allison V. Armour / William Henry Holmes 1895 Expedition to Mexico

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    Warren Haskin

    2001-11-01

    Full Text Available The foundation of the Field Museum's reputation as a place where serious science is practiced was laid by Allison V. Armour and William Henry Holmes in 1895, a little more than a year after the Museum was established. Looking back after a career of almost 60 years as an anthropologist, and having twice been honored as the outstanding practitioner in the field, Holmes described the trip to Mexico (the only expedition he led during his brief tenure as the Museum's first Curator of An­thropology as "one of the most gratifying and important events of my life." It was also one of the most important events in the history of anthropology at the Museum.

  12. Natural Hazard Problem and Solution Definition in the News Media: the Case of Tropical Storm Allison

    Science.gov (United States)

    Lindquist, Eric; Mosher-Howe, Katrina

    2010-05-01

    Focusing events such as natural or technological disasters can have significant impacts on public policy and planning in both the near and long term. These impacts can manifest at different temporal scales ranging from the period of immediate attention and disaster relief through the period of recovery and reconstruction and beyond. These impacts and associated decisions can be studied in retrospect and understood as not only short-term reactions, but as long-term components of subsequent natural hazard planning and public policy. By studying in detail how an event was defined, and the policy and planning alternatives that were raised or recommended in response to a disaster event, we can better understand the role that disaster-related focusing events play in the long-term evolution of a community's public policy, infrastructural planning efforts, and responses to natural disasters. This paper will use a focusing event framework to explore the local and regional policy impacts over time of a major urban flood in Houston, Texas, Tropical Storm Allison. Tropical Storm Allison (TSA), dropped 36 inches of rain on Houston over a period of four days in early June 2001, and was responsible for 22 deaths, 70,000 flood damaged homes, and 5 billion in damage to the region. The primary data source for this effort is a database of 500 articles from the major regional newspaper, the Houston Chronicle, over the period of 2001 through 2008. These articles were coded for multiple variables, including, cause, effect and impact (financial and social), blame, problem and solution definition and solution acceptance). This paper focuses primarily on the measures of problem definition (how was TSA, as an event, defined in the media, for example, as an act of God, or as a result of poor planning or decision making, etc), and on solution definition (what solutions were proposed to mitigate or adapt to future storms of this magnitude, how were they linked to the definition of the problem

  13. Celebrating Queer Lesbian Desires with Dorothy Allison: From moral monstrosity to the beautiful materiality of the body

    Directory of Open Access Journals (Sweden)

    Mélanie Grué

    2015-01-01

    Using social and queer theory on domination, sexuality and gender, this contribution explores how the queer American author Dorothy Allison celebrates the vilified transgressive lesbian body. As, in the 1970s, the mainstream american feminist movement crystallized around the definition of an acceptable sexuality in the name of femininity, female sexual practices were standardized according to strict identity frames, carnal desire was denied, and transgressive lesbians who play with gender roles were defined as abject. In response to this extreme taming of the body, Allison interrogates the notions of masculinity and femininity, domination and submission in her exploration of sexual pleasure and traumatized sexuality. She celebrates the aggressiveness and masculinity of queer lesbianism, promotes the fluidity of gender roles, and asserts the primacy of the flesh,sensuality, and materiality in sexuality.

  14. Object lessons: notes on geometry in Norman Allison Calkins’ textbook (Brazil, end of nineteenth century, beginning of twentieth century

    Directory of Open Access Journals (Sweden)

    Maria Laura Magalhães Gomes

    2011-12-01

    Full Text Available Primary object lessons, by Norman Allison Calkins, ranslated by Rui Barbosa, a book that was widely disseminated in Brazil during the final years of the 19th century and the beginning of the 20th century, presents object teaching as a general method to be used in every subject or primary school. This article analyses Calkins’ book according to its presentation of mathematical content, focusing particularly on geometry lessons. It also iscusses five features of the approach adopted by Calkins: the presentation of plane geometry before geometry in space, the several materials necessary to the teaching of geometry, the drawing lessons associated with the lessons on shape, the sequence of presentation of the contents and the relations between geometry teaching and children’s pleasure and curiosity. Comments about the utilization and circulation of Calkins’ manual in geometry teaching in Brazil are also provided.

  15. Pediatric MS

    Science.gov (United States)

    ... Pediatric MS Share this page Facebook Twitter Email Pediatric MS Pediatric MS Pediatric MS Support Pediatric Providers ... system through the Pediatric MS Support Group . Treating pediatric MS In 2018 the U.S. Food and Drug ...

  16. Analysis of an Attenuator Artifact in an Experimental Attack by Gunn-Allison-Abbott Against the Kirchhoff-Law-Johnson-Noise (KLJN) Secure Key Exchange System

    Science.gov (United States)

    Kish, Laszlo B.; Gingl, Zoltan; Mingesz, Robert; Vadai, Gergely; Smulko, Janusz; Granqvist, Claes-Göran

    2015-12-01

    A recent paper by Gunn-Allison-Abbott (GAA) [L. J. Gunn et al., Scientific Reports 4 (2014) 6461] argued that the Kirchhoff-law-Johnson-noise (KLJN) secure key exchange system could experience a severe information leak. Here we refute their results and demonstrate that GAA's arguments ensue from a serious design flaw in their system. Specifically, an attenuator broke the single Kirchhoff-loop into two coupled loops, which is an incorrect operation since the single loop is essential for the security in the KLJN system, and hence GAA's asserted information leak is trivial. Another consequence is that a fully defended KLJN system would not be able to function due to its built-in current-comparison defense against active (invasive) attacks. In this paper we crack GAA's scheme via an elementary current-comparison attack which yields negligible error probability for Eve even without averaging over the correlation time of the noise.

  17. On the “Cracking” Scheme in the Paper “A Directional Coupler Attack Against the Kish Key Distribution System” by Gunn, Allison and Abbott

    Directory of Open Access Journals (Sweden)

    Chen Hsien-Pu

    2014-08-01

    Full Text Available Recently, Gunn, Allison and Abbott (GAA [http://arxiv.org/pdf/1402.2709v2.pdf] proposed a new scheme to utilize electromagnetic waves for eavesdropping on the Kirchhoff-law-Johnson-noise (KLJN secure key distribution. We proved in a former paper [Fluct. Noise Lett. 13 (2014 1450016] that GAA’s mathematical model is unphysical. Here we analyze GAA’s cracking scheme and show that, in the case of a loss-free cable, it provides less eavesdropping information than in the earlier (Bergou-Scheuer-Yariv mean-square-based attack [Kish LB, Scheuer J, Phys. Lett. A 374:2140-2142 (2010], while it offers no information in the case of a lossy cable. We also investigate GAA’s claim to be experimentally capable of distinguishing—using statistics over a few correlation times only—the distributions of two Gaussian noises with a relative variance difference of less than 10-8. Normally such distinctions would require hundreds of millions of correlations times to be observable. We identify several potential experimental artifacts as results of poor KLJN design, which can lead to GAA’s assertions: deterministic currents due to spurious harmonic components caused by ground loops, DC offset, aliasing, non-Gaussian features including non-linearities and other non-idealities in generators, and the timederivative nature of GAA’s scheme which tends to enhance all of these artifacts.

  18. Late Paleocene-middle Eocene benthic foraminifera on a Pacific seamount (Allison Guyot, ODP Site 865): Greenhouse climate and superimposed hyperthermal events

    Science.gov (United States)

    Arreguín-Rodríguez, Gabriela J.; Alegret, Laia; Thomas, Ellen

    2016-03-01

    We investigated the response of late Paleocene-middle Eocene (~60-37.5 Ma) benthic foraminiferal assemblages to long-term climate change and hyperthermal events including the Paleocene-Eocene Thermal Maximum (PETM) at Ocean Drilling Program (ODP) Site 865 on Allison Guyot, a seamount in the Mid-Pacific Mountains. Seamounts are isolated deep-sea environments where enhanced current systems interrupt bentho-pelagic coupling, and fossil assemblages from such settings have been little evaluated. Assemblages at Site 865 are diverse and dominated by cylindrical calcareous taxa with complex apertures, an extinct group which probably lived infaunally. Dominance of an infaunal morphogroup is unexpected in a highly oligotrophic setting, but these forms may have been shallow infaunal suspension feeders, which were ecologically successful on the current-swept seamount. The magnitude of the PETM extinction at Site 865 was similar to other sites globally, but lower diversity postextinction faunas at this location were affected by ocean acidification as well as changes in current regime, which might have led to increased nutrient supply through trophic focusing. A minor hyperthermal saw less severe effects of changes in current regime, with no evidence for carbonate dissolution. Although the relative abundance of infaunal benthic foraminifera has been used as a proxy for surface productivity through bentho-pelagic coupling, we argue that this proxy can be used only in the absence of changes in carbonate saturation and current-driven biophysical linking.

  19. DEGAM-Leitlinien als App für Mobiltelefone – Einsatz, Anregungen und Nutzen für den Lernprozess von Studierenden im Fach Allgemeinmedizin [Smartphone Application of Primary Care Guidelines used in Education of Medical Students

    Directory of Open Access Journals (Sweden)

    Waldmann, Uta-Maria

    2013-02-01

    knowledge, particularly through its use in waiting periods and the attractive medium smartphone. However, the latter prevents a mandatory curricular use in compulsory courses, since not all students use smartphones. It is a meaningful addition to existing teaching materials and supports evidence-based teaching in Family Medicine and is suitable for use not only in university course teaching but also during clinical training. [german] Hintergrund und Fragestellung: Die Leitlinien der Deutschen Gesellschaft für Allgemeinmedizin (DEGAM zu häufigen und wichtigen Beratungsanlässen in der Hausarztpraxis sind ein zentraler Inhalt der Lehre im Fach Allgemeinmedizin. Durch die Autoren wurden sie als App für Mobiltelefone aufbereitet und stehen somit nun Hausärzten und Studierenden jederzeit zur Verfügung. Die vorliegende Studie untersucht die Fragestellung: Wie bewerten Studierende den Nutzen dieser Anwendung für ihren Lernprozess im Fach Allgemeinmedizin?Methodik: Die Kurzversionen der 15 DEGAM-Leitlinien wurden als (Smartphone-Betriebssystem-unabhängige Web-App mit Möglichkeit der Offline-Nutzung umgesetzt und Studierenden in Kurs, Blockpraktikum, Wahlfächern und PJ (Praktisches Jahr Allgemeinmedizin angeboten. Die Evaluation erfolgte durch eine strukturierte Befragung über die Feedbackfunktion der Moodle-Lernplattform www.elearning-allgemeinmedizin.de mit Likertskalen und Freitextkommentaren.Ergebnisse: Der Evaluations-Rücklauf kam von 14 (25% der 56 studentischen TesterInnen aus dem Kurs Allgemeinmedizin (9, dem Blockpraktikum (1, dem PJ (1 und Wahlfächern (4. Die App selbst sehen die Studierenden als Mehrwert zur Print/PDF-Version. Sie nutzen sie häufig und erfolgreich in Nischenzeiten und vor/während/nach Lehrveranstaltungen. Neben allgemeinem Interesse / Kennenlernen der Leitlinien und Lernen wird sie zum Nachschlagen konkreter (theoretischer Fragestellungen eingesetzt, weniger im Zusammenhang mit Patientenkontakten. Interesse und Kenntnis der Leitlinien wird

  20. Frontalunterricht oder interaktive Gruppenarbeit? Ein Vergleich des Lernerfolgs und der studentischen Evaluation für das Fach Biochemie [Didactic lecture or interactive group discussion? A comparison of the learning success and the student evaluation in biochemistry

    Directory of Open Access Journals (Sweden)

    Kadmon, Martina

    2009-05-01

    Unterrichtsformen bisher nur wenig erprobt. Die vorliegende Studie wurde mit dem Ziel durchgeführt, herauszufinden, welchen Einfluss die Unterrichtsform auf den Wissenszuwachs und die studentische Beurteilung des Biochemie-Unterrichts hat. Methodik: Studierende des 4. Fachsemesters (n=421 wurden für eine Seminarveranstaltung in zwei Gruppen randomisiert. Die Kontrollgruppe erhielt konventionellen Frontalunterricht, die Studiengruppe erarbeitete sich dieselben Lerninhalte anhand konkreter Fragestellungen in interaktiven Arbeitsgruppen. Als Messinstrument zur Beurteilung des kognitiven Erfolges diente ein Wissenstest unmittelbar nach der Veranstaltung und nach 4-6 Wochen. Die Beurteilung der beiden Unterrichtsformen durch die Studierenden erfolgte anhand eines Fragebogens. Ergebnisse: Studierende, die Frontalunterricht erhielten, schnitten in einem ersten Wissenstest, direkt nach der Veranstaltung, signifikant besser ab als Studierende, die sich die Inhalte in interaktiven Gruppen selbst erarbeiteten. Im Wiederholungstest waren keine signifikanten Wissensunterschiede mehr messbar. In der Evaluation beurteilten Studierende, die Frontalunterricht erhielten, die Veranstaltung signifikant besser als diejenigen, die in Gruppen arbeiteten. Schlussfolgerung: Die schlechtere studentische Bewertung der interaktiven Unterrichtsform gegenüber Frontalunterricht in einem Biochemieseminar kann verschiedene Ursachen haben. Eine Ursache könnte die starke Orientierung des Faches an Faktenwissen sein. Dieses Wissen wurde nach Meinung der Studierenden - in dem in dieser Studie gegebenen Rahmen – vom Dozenten besser vermittelt als es in einer interaktiven Gruppenarbeit von Studierenden selbst erarbeitet werden konnte. Andere Ursachen könnten Prüfungsmethoden und curriculare Vorgaben sein.

  1. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Area Donate Donate Search v What Is MS? Definition of MS What Causes MS? Who Gets MS? ... Support Personal Stories d What Is MS? d Definition of MS Myelin Immune-Mediated Disease T Cells ...

  2. MS in Your Relationships

    Science.gov (United States)

    ... MS Relationships Share this page Facebook Twitter Email Relationships MS poses additional challenges, but it also enriches ... when it is not. Keeping balance in your relationship When one person in a couple is affected ...

  3. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... d Living Well with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing MS and Another Condition Aging with MS Anesthesia and Surgery Managing Your MS ...

  4. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Definition of MS Myelin Immune-Mediated Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters ... d Research News & Progress Research News MSPARIS2017 Stem Cells in MS Progressive MS Research Clinical Trials in ...

  5. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... to navigation Skip to content Menu Navigation National Multiple Sclerosis Society Sign In In Your Area Donate Donate ... of MS What Causes MS? Who Gets MS? Multiple Sclerosis FAQs Types of MS Related Conditions Symptoms & Diagnosis ...

  6. Sensitivity of GC-EI/MS, GC-EI/MS/MS, LC-ESI/MS/MS, LC-Ag(+) CIS/MS/MS, and GC-ESI/MS/MS for analysis of anabolic steroids in doping control.

    Science.gov (United States)

    Cha, Eunju; Kim, Sohee; Kim, Ho Jun; Lee, Kang Mi; Kim, Ki Hun; Kwon, Oh-Seung; Lee, Jaeick

    2015-01-01

    This study compared the sensitivity of various separation and ionization methods, including gas chromatography with an electron ionization source (GC-EI), liquid chromatography with an electrospray ionization source (LC-ESI), and liquid chromatography with a silver ion coordination ion spray source (LC-Ag(+) CIS), coupled to a mass spectrometer (MS) for steroid analysis. Chromatographic conditions, mass spectrometric transitions, and ion source parameters were optimized. The majority of steroids in GC-EI/MS/MS and LC-Ag(+) CIS/MS/MS analysis showed higher sensitivities than those obtained with other analytical methods. The limits of detection (LODs) of 65 steroids by GC-EI/MS/MS, 68 steroids by LC-Ag(+) CIS/MS/MS, 56 steroids by GC-EI/MS, 54 steroids by LC-ESI/MS/MS, and 27 steroids by GC-ESI/MS/MS were below cut-off value of 2.0 ng/mL. LODs of steroids that formed protonated ions in LC-ESI/MS/MS analysis were all lower than the cut-off value. Several steroids such as unconjugated C3-hydroxyl with C17-hydroxyl structure showed higher sensitivities in GC-EI/MS/MS analysis relative to those obtained using the LC-based methods. The steroids containing 4, 9, 11-triene structures showed relatively poor sensitivities in GC-EI/MS and GC-ESI/MS/MS analysis. The results of this study provide information that may be useful for selecting suitable analytical methods for confirmatory analysis of steroids. Copyright © 2015 John Wiley & Sons, Ltd.

  7. Ms. Mentor Unmasked

    Science.gov (United States)

    Krebs, Paula

    2008-01-01

    This article presents an interview with Emily Toth, who writes the monthly "Ms. Mentor" academic advice column in the "Chronicle of Higher Education" and teaches in the English department at Louisiana State University, in Baton Rouge. She is the author of "Ms. Mentor's Impeccable Advice for Women in Academia" (1997), "Inside Peyton Place: The Life…

  8. Human herpesviruses and MS

    DEFF Research Database (Denmark)

    Christensen, Tove

    2007-01-01

    and they are capable of reactivation. Epstein Barr virus (EBV), HHV-6A and varicella zoster virus (VZV) are consistently linked with MS, particularly with respect to epidemiology, antibody responses in serum (EBV) and cerebrospinal fluid (EBV and HHV-6A), and with MS exacerbations that are associated with viral...... reactivation (VZV, HHV-6A and EBV). HHV have the potential for a causal role in MS--they may be key players in the disease process--and this role could be mediated through several direct or indirect mechanisms....

  9. Living with Advanced MS

    Science.gov (United States)

    ... Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing ... as well as other resources in your area. Learning to redefine control and independence Sometimes MS symptoms ...

  10. MS Based Metabonomics

    Energy Technology Data Exchange (ETDEWEB)

    Want, Elizabeth J.; Metz, Thomas O.

    2010-03-01

    Metabonomics is the latest and least mature of the systems biology triad, which also includes genomics and proteomics, and has its origins in the early orthomolecular medicine work pioneered by Linus Pauling and Arthur Robinson. It was defined by Nicholson and colleagues in 1999 as the quantitative measurement of perturbations in the metabolite complement of an integrated biological system in response to internal or external stimuli, and is often used today to describe many non-global types of metabolite analyses. Applications of metabonomics are extensive and include toxicology, nutrition, pharmaceutical research and development, physiological monitoring and disease diagnosis. For example, blood samples from millions of neonates are tested routinely by mass spectrometry (MS) as a diagnostic tool for inborn errors of metabolism. The metabonome encompasses a wide range of structurally diverse metabolites; therefore, no single analytical platform will be sufficient. Specialized sample preparation and detection techniques are required, and advances in NMR and MS technologies have led to enhanced metabonome coverage, which in turn demands improved data analysis approaches. The role of MS in metabonomics is still evolving as instrumentation and software becomes more sophisticated and as researchers realize the strengths and limitations of current technology. MS offers a wide dynamic range, high sensitivity, and reproducible, quantitative analysis. These attributes are essential for addressing the challenges of metabonomics, as the range of metabolite concentrations easily exceeds nine orders of magnitude in biofluids, and the diversity of molecular species ranges from simple amino and organic acids to lipids and complex carbohydrates. Additional challenges arise in generating a comprehensive metabolite profile, downstream data processing and analysis, and structural characterization of important metabolites. A typical workflow of MS-based metabonomics is shown in Figure

  11. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... of Distinction Lawry Circle Circle of Influence d Planned Giving d Other Ways to Give Donate by ...

  12. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... Review of Society's Research Programs d Careers d Leadership Board of Directors Senior Leadership Team Founder Sylvia ...

  13. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... for You and Your Practice Publications for Clinicians Publications for Your Patients MS Navigator Program Programs and Services for Your Patients ... Relapsing-remitting MS (RRMS) Relapsing-remitting MS ( ...

  14. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... times as often as men; in PPMS, the number of women and men are approximately equal. RRMS ...

  15. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Disease T Cells d What Causes MS? Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS ... Community at MSconnection.org Join a Local Support Group Peer Connections: One-on-One Edward M. Dowd ...

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    Full Text Available ... Trials in MS Wellness and Lifestyle Research Diet Vitamin D How and Why Do Scientists Share Results ... The National MS Society is Here to Help Need More Information? We Are Here Our MS Navigators ...

  17. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... working effectively. How does RRMS differ from progressive types of MS? While RRMS is defined by attacks ... Pinterest MS Connection About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence ...

  18. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Viruses Clusters d Who Gets MS? Pediatric MS African Americans Hispanics & Latino/as d Multiple Sclerosis FAQs d ... Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing MS and Another Condition ...

  19. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Disproved Theories Viruses Clusters d Who Gets MS? Pediatric MS African Americans Hispanics & Latino/as d Multiple ... Questions to Ask d Resources for Specific Populations Pediatric MS Support Veterans with Multiple Sclerosis d Find ...

  20. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Room Events at a Glance MS the Disease Public Service Announcements In the News Archives d MS ... For Professionals Researchers Physicians Nurses Rehabilitation Professionals Mental Health Professionals Health and Wellness Professionals What Is MS? ...

  1. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Conditions to Rule Out For Clinicians Treating MS Comprehensive Care Find an MS Care Provider Medications Managing ... ADEM) d For Clinicians d Treating MS d Comprehensive Care Developing a Healthcare Team Make the Most ...

  2. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... the Challenges of MS You CAN! Webcasts DVDs Books For Kids: Keep S'myelin Información en Español Brochures ... Managing MS and Another Condition Aging with MS Anesthesia and Surgery Managing Your MS d Emotional Well- ...

  3. Determination of Glyphosate Levels in Breast Milk Samples from Germany by LC-MS/MS and GC-MS/MS

    NARCIS (Netherlands)

    Steinborn, Angelika; Alder, Lutz; Michalski, Britta; Zomer, Paul; Bendig, Paul; Martinez, Sandra Aleson; Mol, Hans G.J.; Class, Thomas J.; Costa Pinheiro, Nathalie

    2016-01-01

    This study describes the validation and application of two independent analytical methods for the determination of glyphosate in breast milk. They are based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS), respectively. For

  4. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... MS Relapsing-remitting MS (RRMS) Share this page Facebook Twitter Email Relapsing-remitting MS (RRMS) Relapsing-remitting ... Here Start Here Colophon Stay Informed Join Us Facebook Twitter LinkedIn YouTube Pinterest MS Connection About the ...

  5. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... the Challenges of MS You CAN! Webcasts DVDs Books For Kids: Keep S'myelin Información en Español Brochures ... MS Managing MS Resources for You and Your Practice Publications for Clinicians Publications for Your Patients MS ...

  6. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Relapsing-remitting MS (RRMS) Share this page Facebook Twitter Email Relapsing-remitting MS (RRMS) Relapsing-remitting MS ( ... Start Here Colophon Stay Informed Join Us Facebook Twitter LinkedIn YouTube Pinterest MS Connection About the Society ...

  7. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Become an MS Activist Take Action Current Advocacy Issues Advocacy Results Advocacy News d Raise Awareness d ... MS are more likely to experience gradually worsening problems with walking and mobility, along with whatever other symptoms they may have. Diagnosing relapsing-remitting MS (RRMS) Learn More Learn More ... Room MS Prevalence ...

  8. ICP-MS Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Carman, April J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Eiden, Gregory C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-11-01

    This is a short document that explains the materials that will be transmitted to LLNL and DNN HQ regarding the ICP-MS Workshop held at PNNL June 17-19th. The goal of the information is to pass on to LLNL information regarding the planning and preparations for the Workshop at PNNL in preparation of the SIMS workshop at LLNL.

  9. Landeskunde und Interkulturelles Lernen im Fach DaF

    OpenAIRE

    Adam-Cevizoğlu, Claudia

    2011-01-01

    The mediation of German cultural studies has become a firm component of the foreign language lessons, because without knowledge about the culture of the target language communication cannot succeed. However, the aim of the study of the German cultural study lessons should not be to provide a comprehensive picture for the purposes of the actual study of the culture and geography, but to choose from the contents with the help of which then an intercultural competence can be developed. The conce...

  10. MALDI-TOF MS/MS measurements of PMMA

    NARCIS (Netherlands)

    Becer, C.R.; Baumgaertel, A.; Gottschaldt, M.; Schubert, U.S.

    2008-01-01

    The polymer poly(Me methacrylate) (PMMA) was analyzed using the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) technique. The MALDI-TOF MS app. was coupled with a collision-induced dissocn. (CID) unit. The performance of the MALDI-TOF/TOF MS method in

  11. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Contact Us Newly Diagnosed If you or somone close to you has recently been diagnosed, access our MS information and resources. Start ... Room MS Prevalence Charitable Ratings Corporate Support Helpful Links ...

  12. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Events Living Well with MS Diet, Exercise & Healthy Behaviors Emotional Well-Being Spiritual Well-Being Cognitive Health ... Living Well with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations ...

  13. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Clinicians Publications for Your Patients MS Navigator Program Programs and Services for Your Patients Contact Us Clinical Fellows ... Relapsing-remitting MS (RRMS) Relapsing-remitting ...

  14. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Programs and Events Living Well with MS Diet, Exercise & Healthy Behaviors Emotional Well-Being Spiritual Well-Being ... Events d Living Well with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity ...

  15. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Treating MS Comprehensive Care Find an MS Care Provider Medications Managing Relapses Rehabilitation Complementary & Alternative Medicines For Clinicians Resources & Support Library & Education Programs Find Support Advanced Care ...

  16. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... working effectively. How does RRMS differ from progressive types of MS? While RRMS is defined by attacks ... forms of MS involve much less of this type of inflammation. People with RRMS tend to have ...

  17. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... of Programs and Events Living Well with MS Diet, Exercise & Healthy Behaviors Emotional Well-Being Spiritual Well- ... and Events d Living Well with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature ...

  18. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Rule Out For Clinicians Treating MS Comprehensive Care Find an MS Care Provider Medications Managing Relapses Rehabilitation ... Medicines For Clinicians Resources & Support Library & Education Programs Find Support Advanced Care Needs Resources for Specific Populations ...

  19. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... bowel and bladder problems, and problems with cognition (learning and memory or information processing). People with progressive ... More The National MS Society is Here to Help Need More Information? We Are Here Our MS ...

  20. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Brochure Working with MS (.pdf) Download Brochure Taming Stress (.pdf) Download Brochure Multiple Sclerosis and Your Emotions (. ... For Professionals Researchers Physicians Nurses Rehabilitation Professionals Mental Health Professionals Health and Wellness Professionals What Is MS? ...

  1. Progressive-Relapsing MS (PRMS)

    Science.gov (United States)

    ... Is MS? Types of MS Share this page Facebook Twitter Email ... multiple sclerosis (PRMS) was described in the 1996 disease-course definitions as — steadily worsening neurologic function from the beginning ...

  2. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... d Spiritual Well-Being Building Spirituality into Your Life d Cognitive Health d Work, Home & Leisure Employment ... Partnership Opportunities d Personal Stories Ambassadors & Familiar Faces Life with MS Givers Shakers Families with MS Seekers ...

  3. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Your Practice Publications for Clinicians Publications for Your Patients MS Navigator Program Programs and Services for Your Patients Contact Us Clinical Fellows d Careers in MS ...

  4. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Life d Cognitive Health d Work, Home & Leisure Employment Insurance & Financial Information Staying Mobile Reclaiming Control Accessibility ... Living with MS (.pdf) Download Brochure Focus on Employment (.pdf) Download Brochure Working with MS (.pdf) Download ...

  5. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Online d Give in Honor or Memory d Workplace Giving d Employer Matching Gifts d Gifts of ... Living with MS (.pdf) Download Brochure Focus on Employment (.pdf) Download Brochure Working with MS (.pdf) Download ...

  6. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Associated Myelopathy (HAM) Neuromyelitis Optica (NMO) Schilder's Disease Transverse Myelitis d Symptoms & Diagnosis d Diagnosing MS d ... Overview (.pdf) Download Document Pediatric MS Learn More Transverse Myelitis Learn More Neuromyelitis Optica (NMO) Learn More ...

  7. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... attacks of inflammation (relapses) in the CNS, progressive forms of MS involve much less of this type ... and memory or information processing). People with progressive forms of MS are more likely to experience gradually ...

  8. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... working effectively. How does RRMS differ from progressive types of MS? While RRMS is defined by attacks of ... forms of MS involve much less of this type of inflammation. People with RRMS tend to have more ...

  9. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Directors Senior Leadership Team Founder Sylvia Lawry d Cultural Values d Financials Annual Reports Sources of Support ... MS Connection About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence Charitable ...

  10. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... and problems with cognition (learning and memory or information processing). People with progressive forms of MS are more likely to experience gradually worsening problems with walking and mobility, along with whatever other symptoms they may have. Diagnosing ... MS Society is Here to Help Need More Information? We Are Here Our MS Navigators help identify ...

  11. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Living Well with MS Diet, Exercise & Healthy Behaviors Emotional Well-Being Spiritual Well-Being Cognitive Health Work, ... MS Anesthesia and Surgery Managing Your MS d Emotional Well-Being Mood Changes d Spiritual Well-Being ...

  12. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Treating MS d Comprehensive Care Developing a Healthcare Team Make the Most of Your Doctor Visits Advance Medical Directives d Find an MS Care Provider Partners in MS Care d Managing Relapses Plasmapheresis d Rehabilitation Functional Electrical Stimulation (FES) ...

  13. LC-MS (/MS) in clinical toxicology screening methods.

    Science.gov (United States)

    Viette, Véronique; Hochstrasser, Denis; Fathi, Marc

    2012-01-01

    Toxicological screening is the analysis of biological samples to detect and identify unknown compounds. The high selectivity and sensitivity of liquid chromatography (LC) coupled to mass spectrometry (MS) or tandem mass spectrometry (MS/MS) technology provide an attractive alternative to the current methods (LC-UV, GC/MS, etc.). For these reasons, an increasing number of applications are being published. This paper is a brief overview of LC-MS(/MS) screening methods developed for clinical toxicology in recent years. Various sample treatments, chromatographic separations and detection by mass spectrometry can be combined to obtain screening methods adapted to the constraints and needs of clinical toxicology laboratories. Currently the techniques are in the hands of specialists, mainly in academic institutions. However, the evolution in technology should allow application of these techniques as a tool in toxicology laboratories, thus allowing a more widespread exploitation of their potential.

  14. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Brochure Working with MS (.pdf) Download Brochure Taming Stress (.pdf) Download Brochure Multiple Sclerosis and Your Emotions (.pdf) Download Brochure Disease Modifying Therapies Overview (.pdf) ...

  15. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Privacy Policy Site Map Site Tour Contact Us For Professionals Researchers Physicians Nurses Rehabilitation Professionals Mental Health Professionals Health and Wellness Professionals What Is MS? ...

  16. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence Charitable Ratings Corporate Support Helpful Links Donate Society Store MSConnection Blog ...

  17. Rootkit pro MS Windows

    OpenAIRE

    Trutman, Michal

    2012-01-01

    Tato bakalářská práce se zabývá metodami útoků na operační systém MS Windows a přibližuje techniky skrývání výpočetních prostředků používané existujícími rootkity. Práce je rozdělena na teoretickou a praktickou část. První část pojednává o klasifikaci rootkitů, představuje strukturu jádra systému a následně popisuje jednotlivé techniky napadení operačního systému. V praktické části je prezentována implementace a testování vlastního rootkitu. This bachelor's thesis deals with methods of att...

  18. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Another Condition Aging with MS Anesthesia and Surgery Managing Your MS d Emotional Well-Being Mood Changes d Spiritual Well-Being Building Spirituality into Your Life d Cognitive Health d Work, Home & Leisure Employment Insurance & Financial Information Staying Mobile ...

  19. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Review of Society's Research Programs d Careers d Leadership Board of Directors Senior Leadership Team Founder Sylvia Lawry d Cultural Values d ... Pinterest MS Connection About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence ...

  20. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Text Print Discover More Here are a few related topics that may interest you Living with MS (.pdf) Download Brochure Focus on Employment (.pdf) Download Brochure Working with MS (.pdf) Download Brochure Taming Stress (.pdf) Download Brochure Multiple Sclerosis and Your Emotions (. ...

  1. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... More Schilder's Disease Learn More The National MS Society is Here to Help Need More Information? We ... Twitter LinkedIn YouTube Pinterest MS Connection About the Society Vision Careers Leadership Cultural Values Financials News Press ...

  2. Changing activity in MS lesions

    International Nuclear Information System (INIS)

    Kermode, A.G.; Tofts, P.S.; Thompson, A.J.; Rudge, P.; MacManus, D.G.; Kendall, B.E.; Moseley, I.F.; Kingsley, D.P.E.; McDonald, W.I.

    1989-01-01

    Gd-DTPA enhanced T1 weighted MRI is a discriminating test for a defective blood-brain barrier, with MS lesions showing considerable variation in the pattern of enhancement. Since little is known of the changes in the blood-brain barrier in the active plaque over time, the natural history of blood-brain barrier disturbance in the MS lesion was examined to confirm earlier reports that Gd-DTPA enhancement is a consistent early event in new lesions of relapsing/remitting MS. This knowledge is essential for the use of MRI in monitoring treatment. (author). 9 refs

  3. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Behaviors Emotional Well-Being Spiritual Well-Being Cognitive Health Work, Home & Leisure Relationships Research Participate in Research ... Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing MS and Another Condition Aging ...

  4. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... you and your MS care provider discuss your treatment options and expected outcomes. For example: If you ... will likely want to consider a more aggressive treatment approach than if there were no evidence of ...

  5. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Research Diet Vitamin D How and Why Do Scientists Share Results d Research We Fund Stopping MS ... Share Smaller Text Larger Text Print In this article Overview RRMS – the most common disease course – is ...

  6. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... membranes surrounding nerve fibers in the central nervous system (CNS)), as well as the nerve fibers themselves. ... and problems with cognition (learning and memory or information processing). People with progressive forms of MS are ...

  7. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... discuss your treatment options and expected outcomes. For example: If you have RRMS that is active and worsening, you and your MS care provider will likely want to consider a more aggressive treatment approach than if there ...

  8. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Electrical Stimulation (FES) d Complementary & Alternative Medicines Chiropractic Therapy Marijuana Massage and Bodywork Acupuncture d For Clinicians ... you and your MS care provider discuss your treatment options and expected outcomes. For example: If you ...

  9. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Webinar Series Momentum Magazine Educational Videos Knowledge Is Power Live Fully, Live Well Everyday Matters Resilience: Addressing ... d Living Well with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep ...

  10. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Webinar Series Momentum Magazine Educational Videos Knowledge Is Power Live Fully, Live Well Everyday Matters Resilience: Addressing the Challenges of MS You CAN! Webcasts DVDs Books ...

  11. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Find Support Advanced Care Needs Resources for Specific Populations Find Programs & Services in Your Area Calendar of ... Services: Questions to Ask d Resources for Specific Populations Pediatric MS Support Veterans with Multiple Sclerosis d ...

  12. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... in RRMS; however, each person's experience with RRMS will be unique. Following a relapse, the new symptoms ... and worsening, you and your MS care provider will likely want to consider a more aggressive treatment ...

  13. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Senior Leadership Team Founder Sylvia Lawry d Cultural Values d Financials Annual Reports Sources of Support d ... Connection About the Society Vision Careers Leadership Cultural Values Financials News Press Room MS Prevalence Charitable Ratings ...

  14. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing MS and Another Condition ... lesions, which contain fewer inflammatory cells. In RRMS, women are affected two to three times as often ...

  15. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... CIS) Newly Diagnosed Diagnosing Tools Other Conditions to Rule Out For Clinicians Treating MS Comprehensive Care Find ... CSF) Evoked Potentials (EP) d Other Conditions to Rule Out Lyme Disease Lupus Neuromyelitis Optica Acute Disseminated ...

  16. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Become an MS Activist Take Action Current Advocacy Issues Advocacy Results Advocacy News ... d Give in Honor or Memory d Workplace Giving d Employer Matching Gifts d Gifts of ...

  17. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... without symptoms of which the person is aware. What happens in RRMS? Relapsing-remitting MS is defined ... a different mechanism of action in order to control the disease activity more effectively and help prevent ...

  18. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health Unhealthy Habits Managing MS and Another ... or worsening. Together, you can weigh the potential risks and benefits of other treatment options. If your ...

  19. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... An increase in disability is confirmed when the person exhibits the same level of disability at the ... to 12 months later. Approximately 85 percent of people with MS are initially diagnosed with RRMS. This ...

  20. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Support d Library & Education Programs Email newsletter Mood Changes Webinar Series Momentum Magazine Educational Videos Knowledge Is Power Live Fully, Live Well Everyday Matters Resilience: Addressing the Challenges of MS You CAN! Webcasts DVDs Books For ...

  1. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Employer Matching Gifts d Gifts of Stock or Securities d Giving Circles Golden Circle Circle of Distinction ... Your Practice Publications for Clinicians Publications for Your Patients MS Navigator Program Programs and Services for Your ...

  2. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... 344-4867 or contact us online. Contact Us Contact Us Newly Diagnosed If you or somone close to you has recently been diagnosed, access our MS information ... Connection About the Society Vision ...

  3. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Research Diet Vitamin D How and Why Do Scientists Share Results d Research We Fund Stopping MS ... RRMS Treating RRMS Research in RRMS Share Smaller Text Larger Text Print In this article Overview RRMS – ...

  4. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... d Get Involved d Volunteer Volunteer Information Volunteer Recognition d Advocate for Change Become an MS Activist ... d Donate Online d Give in Honor or Memory d Workplace Giving d Employer Matching Gifts d ...

  5. Relapsing-Remitting MS (RRMS)

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    Full Text Available ... Mood Changes Webinar Series Momentum Magazine Educational Videos Knowledge Is Power Live Fully, Live Well Everyday Matters ... with MS d Diet, Exercise & Healthy Behaviors Diet & Nutrition Exercise Heat & Temperature Sensitivity Sleep Vaccinations Women's Health ...

  6. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Employer Matching Gifts d Gifts of Stock or Securities d Giving Circles Golden Circle Circle of Distinction ... and problems with cognition (learning and memory or information processing). People with progressive forms of MS are ...

  7. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Fully, Live Well Everyday Matters Resilience: Addressing the Challenges of MS You CAN! Webcasts DVDs Books For ... Review of Society's Research Programs d Careers d Leadership Board of Directors Senior Leadership Team Founder Sylvia ...

  8. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Women's Health Unhealthy Habits Managing MS and Another Condition ... healthcare provider can feel confident that the current treatment regimen is working effectively. How does RRMS differ from progressive types ...

  9. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Online d Give in Honor or Memory d Workplace Giving d Employer Matching Gifts d Gifts of ... Brochure Working with MS (.pdf) Download Brochure Taming Stress (.pdf) Download Brochure Multiple Sclerosis and Your Emotions (. ...

  10. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Team Make the Most of Your Doctor Visits Advance Medical Directives d Find an MS Care Provider ... in RRMS; however, each person's experience with RRMS will be unique. Following a relapse, the new symptoms ...

  11. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... as shown by the arrows, often occur as part of a relapse. However, new MRI lesions indicating ... course of your disease at different points in time helps you and your MS care provider discuss ...

  12. MRI atlas of MS lesions

    Energy Technology Data Exchange (ETDEWEB)

    Sahraian, Mohammad Ali [Tehran Univ. of Medical Sciences Sina Hospital (Iran). Dept. of Neurology; Radue, Ernst-Wilhelm [Univ. Hospital Basel (Switzerland). Dept. of Neuroradiology

    2008-07-01

    MRI has become the main paraclinical test in the diagnosis and management of multiple sclerosis. We have demonstrated more than 400 pictures of different typical and atypical MS lesions in this atlas. Each image has a teaching point. New diagnostic criteria and differential diagnosis are discussed and the book is supported by a teaching DVD where the reader can see MS lesions in different slices and sequences. (orig.)

  13. Finding of pesticides in fashionable fruit juices by LC-MS/MS and GC-MS/MS.

    Science.gov (United States)

    Tran, Kevin; Eide, David; Nickols, Susan M; Cromer, Michele R; Sabaa-Srur, Armando; Smith, Robert E

    2012-10-15

    Products labelled as containing extracts from two mushrooms (cordyceps plus reishi) and the juices from açaí, goji, mangosteen, noni, pomegranate, and sea buckthorn have been analysed for 174 different pesticides, using the validated QuEChERS method for sample preparation and electrospray LC-MS/MS in the positive ion mode for analysis. Pesticides were found in 10 of the 21 samples analysed. Most pesticides found were below the tolerance levels (1-6 μg/g, depending on the pesticide), but some were not. This included boscalid, dimethomorph, iprovalicarb, pyridaben, pyrimethanil, and imazalil, for which there is no tolerance reported or zero tolerance in any fruit. However, genuine açaí that was harvested in the state of Pará and lyophilised in Rio de Janeiro had no detectable pesticides, when analysed by both LC-MS/MS and GC-MS/MS, which can detect 213 more pesticides and industrial chemicals. Likewise no pesticides were found in one sample each of cordyceps plus reishi, sea buckthorn and noni. Published by Elsevier Ltd.

  14. Analysis of acrylamide by LC-MS/MS and GC-MS in processed Japanese foods.

    Science.gov (United States)

    Ono, H; Chuda, Y; Ohnishi-Kameyama, M; Yada, H; Ishizaka, M; Kobayashi, H; Yoshida, M

    2003-03-01

    Acrylamide concentrations in processed foods (63 samples covering 31 product types) from Japan were analysed by LC-MS/MS and GC-MS methods. The limit of detection and limit of quantification of acrylamide were 0.2 ng x ml(-1) (6 fmol) and 0.8 ng x ml(-1) (22 fmol), respectively, by LC-MS/MS, and those of 2,3-dibromopropionamide derived from acrylamide were 12 ng x ml(-1) (52 fmol) and 40 ng x ml(-1) (170 fmol), respectively, by GC-MS. Repeatability given as RSD was 1000 microg x kg(-1). The concentrations in non-whole potato-based snacks, rice crackers processed by grilling or frying, and candied sweet potatoes were lower compared with those in the potato crisps and the whole potato-based fried snacks. One of the whole potato-based fried snacks, however, showed low acrylamide concentration (instant precooked noodles and won-tons were <100 microg x kg(-1) with only one exception. Roasted barley grains for 'Mugi-cha' tea contained 200-600 microg x kg(-1) acrylamide.

  15. Russell Brains Review of MS.

    Science.gov (United States)

    Murray, Tj

    2011-05-01

    In 1930 there were many conflicting views on the cause, incidence, precipitating factors, inheritance and treatment of multiple sclerosis (MS). A young, London neurologist summarized the state of understanding of the disease with his personal view of many of the uncertain areas, and clarified the thinking for the neurological community at that time. Although his later career was influential in many fields of medicine, and his personal influence was extraordinary in many areas as an author, educator, administrator, opinion leader and historian, his review was an important milestone in the history of MS.

  16. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... the Challenges of MS You CAN! Webcasts DVDs Books For Kids: Keep S'myelin Información en Español Brochures ... RRMS Treating RRMS Research in RRMS Share Smaller Text Larger Text Print In this article Overview RRMS – ...

  17. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Multiple Sclerosis and Your Emotions (.pdf) Download Brochure Disease Modifying Therapies Overview (.pdf) Download Document Pediatric MS Learn More Transverse Myelitis Learn More Neuromyelitis Optica (NMO) Learn More HTLV-I ... Learn More Acute Disseminated Encephalomyelitis (ADEM) Learn More ...

  18. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... for Specific Populations Find Programs & Services in Your Area Calendar of Programs and Events Living Well with MS Diet, Exercise & Healthy Behaviors Emotional Well-Being Spiritual Well-Being Cognitive Health Work, Home & Leisure Relationships Research Participate in ...

  19. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... bowel and bladder problems, and problems with cognition (learning and memory or information processing). People with progressive ... Colophon Stay Informed Join Us Facebook Twitter LinkedIn YouTube Pinterest MS Connection About the Society Vision Careers ...

  20. Relapsing-Remitting MS (RRMS)

    Medline Plus

    Full Text Available ... Información en Español d Site Map d Site Tour d Contact Us d For Professionals d Researchers Society Funding Deadlines Apply Online Funding Policies and Procedures Scientific Peer Reviewers Resources for Researchers d Professional Resource Center About MS ...

  1. Method-MS. Final report

    International Nuclear Information System (INIS)

    Skipperud, L.; Popic, J.M.; Roos, P.; Salminen, S.; Nygren, U.; Sigmarsson, O.; Palsson, S.E.

    2011-05-01

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry (AMS) have shown several advantages compared to traditional methods when measuring long-lived radionuclides. Mass spectrometric methods for determination of very low concentrations of elemental isotopes, and thereby isotopic ratios, have been developed using a variety of ion sources. Although primarily applied to the determination of the lighter stable element isotopes and radioactive isotopes in geological studies, the techniques can equally well be applied to the measurement of activity concentrations of long-lived low-level radionuclides in various samples using 'isotope dilution' methods such as those applied in inductively coupled plasma mass spectrometry (ICP-MS). Due to the low specific activity of long-lived radionuclides, many of these are more conveniently detected using mass spectrometric techniques. Mass spectrometry also enables the individual determination of Pu-239 and Pu-240, which cannot be obtained by alpha spectrometry. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are rapidly growing techniques for the ultra-trace analytical determination of stable and long-lived isotopes and have a wide potential within environmental science, including ecosystem tracers and radio ecological studies. Such instrumentation, of course needs good radiochemical separation, to give best performance. The objectives of the project is to identify current needs and problems within low-level determination of long-lived radioisotopes by ICP-MS, to perform intercalibration and development and improvement of ICP-MS methods for the measurement of radionuclides and isotope ratios and to develop new methods based on modified separation chemistry applied to new auxiliary

  2. Method-MS. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Skipperud, L.; Popic, J.M. (Norwegian Univ. of Life Science (UMB), Isotope Lab. (Norway)); Roos, P. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy, Roskilde (Denmark)); Salminen, S. (Univ. of Helsinki (UH) (Finland)); Nygren, U. (Swedish Defence Research Agency (FOI) (Sweden)); Sigmarsson, O.; Palsson, S.E. (Univ. of Iceland/Icelandic Radiation Protection Institute (Iceland))

    2011-05-15

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry (AMS) have shown several advantages compared to traditional methods when measuring long-lived radionuclides. Mass spectrometric methods for determination of very low concentrations of elemental isotopes, and thereby isotopic ratios, have been developed using a variety of ion sources. Although primarily applied to the determination of the lighter stable element isotopes and radioactive isotopes in geological studies, the techniques can equally well be applied to the measurement of activity concentrations of long-lived low-level radionuclides in various samples using 'isotope dilution' methods such as those applied in inductively coupled plasma mass spectrometry (ICP-MS). Due to the low specific activity of long-lived radionuclides, many of these are more conveniently detected using mass spectrometric techniques. Mass spectrometry also enables the individual determination of Pu-239 and Pu-240, which cannot be obtained by alpha spectrometry. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are rapidly growing techniques for the ultra-trace analytical determination of stable and long-lived isotopes and have a wide potential within environmental science, including ecosystem tracers and radio ecological studies. Such instrumentation, of course needs good radiochemical separation, to give best performance. The objectives of the project is to identify current needs and problems within low-level determination of long-lived radioisotopes by ICP-MS, to perform intercalibration and development and improvement of ICP-MS methods for the measurement of radionuclides and isotope ratios and to develop new methods based on modified separation chemistry applied to new

  3. Analysis of phytochemical variations in dioecious Tinospora cordifolia stems using HPLC/QTOF MS/MS and UPLC/QqQLIT -MS/MS.

    Science.gov (United States)

    Bajpai, Vikas; Singh, Awantika; Chandra, Preeti; Negi, M P S; Kumar, Nikhil; Kumar, Brijesh

    2016-01-01

    The stem of dioecious Tinospora cordifolia (Menispermaceae) is a commonly used traditional Ayurvedic medicine in India having several therapeutic properties. To develop and validate LC-MS methods for the identification and simultaneous quantitation of various secondary metabolites and to study metabolomic variations in the stem of male and female plants. Ethanolic extract of stems were analysed by HPLC/ESI-QTOF-MS/MS for rapid screening of bioactive phytochemicals. High resolution MS and MS/MS in positive ESI mode were used for structural investigation of secondary metabolites. An UPLC/ESI-QqQ(LIT) -MS/MS method in MRM mode was developed and validated for the simultaneous quantitation of five bioactive alkaloids. Identification and characterisation of 36 metabolites including alkaloids, sesquiterpenes and phytoecdysteroids were performed using LC-MS and MS/MS techniques. The bioactive alkaloids such as jatrorrhizine, magnoflorine, isocorydine, palmatine and tetrahydropalmatine were successfully quantified in male and female plants. The mean abundances of magnoflorine jatrorrhizine, and oblongine were significantly (P Phytochemicals in the stem of male and female Tinospora cordifolia showed significant qualitative and quantitative variations. LC-MS and MS/MS methods can be used to differentiate between male and female plants based on their chemical profiles and quantities of the marker bioactive alkaloids. This chemical composition difference was also evident during vegetative stage when there were no male and female flowers. Copyright © 2015 John Wiley & Sons, Ltd.

  4. LC-MS based Metabolomics

    DEFF Research Database (Denmark)

    Magdenoska, Olivera

    . The analytical tools applied for analysis of intracellular metabolites should be capable to cope with the large number of metabolites to be analyzed and the complex matrix in the samples. Therefore the combination of separation and detection techniques is commonly applied for analysis of intracellular........ In the studies conducted during this Ph.D. the developed method was used to understand how the genetic manipulations in various organisms, influence the levels of their intracellular metabolites. The method development was divided into three steps: i) optimization of the MS detection, ii) establishment...... of the MS detection aimed to determine multiple reaction monitoring (MRM) transitions of the analytes and to increase the sensitivity by testing different ion-source parameters and collision energies. This resulted in optimized detection of more than 50 intracellular metabolites. During the optimization...

  5. Molecular analysis of intact preen waxes of Calidris Canutus (Aves: Scolopacidae) by GC/MS and GC/MS/MS

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Dekker, M.H.A.; Piersma, T.

    2000-01-01

    The intact preen wax esters of the red knot Calidris canutus were studied with gas chromatography/mass spectrometry (GC/MS) and GC/MS/MS. In this latter technique, transitions from the molecular ion to fragment ions representing the fatty acid moiety of the wax esters were measured, providing

  6. Selenium speciation analysis of Misgurnus anguillicaudatus selenoprotein by HPLC-ICP-MS and HPLC-ESI-MS/MS

    Science.gov (United States)

    Analytical methods for selenium (Se) speciation were developed using high performance liquid chromatography (HPLC) coupled to either inductively coupled plasma mass spectrometry (ICP-MS) or electrospray ionization tandem mass spectrometry (ESI-MS/MS). Separations of selenomethionine (Se-Met) and sel...

  7. MS-SQL data base programming

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Chang Bae; Kim, Nam Jung; Lee, Hyeong Gyo

    2002-07-15

    This is about MS-SQL data base programming which is divided into thirteen chapters. The contents of this book are to understand MS-SQL 2000 DBMS with its composition, new function and history of MS-SQL, to learn conception of data base, install, run and closing of MS-SQL 2000 DBMS, to deal with the basic of MS-SQL DBMS, to handle the intermediate level of MS-SQL DBMS, to deal with MS-SQL DBMS in advanced level, to practice query like changing data base and checking of data lists, function on its use and data diff, get date, date add, char, upper and system function, set-up of MS-SQL ODBC, constructing of web server of windows 2000, web programming using visual studio.net.making board and making reference room.

  8. MS-SQL data base programming

    International Nuclear Information System (INIS)

    Noh, Chang Bae; Kim, Nam Jung; Lee, Hyeong Gyo

    2002-07-01

    This is about MS-SQL data base programming which is divided into thirteen chapters. The contents of this book are to understand MS-SQL 2000 DBMS with its composition, new function and history of MS-SQL, to learn conception of data base, install, run and closing of MS-SQL 2000 DBMS, to deal with the basic of MS-SQL DBMS, to handle the intermediate level of MS-SQL DBMS, to deal with MS-SQL DBMS in advanced level, to practice query like changing data base and checking of data lists, function on its use and data diff, get date, date add, char, upper and system function, set-up of MS-SQL ODBC, constructing of web server of windows 2000, web programming using visual studio.net.making board and making reference room.

  9. Physical Exercise and MS Recommendations

    DEFF Research Database (Denmark)

    Dalgas, U; Ingemann-Hansen, T; Stenager, E

    2009-01-01

    in a number of physiological functions, which ultimately can lead to functional improvements that have a positive effect on a patients daily life. The purpose of this review is, based on the existing research, to provide clinicians with some easily administrable recommendations for the application of exercise......The use of physical exercise programmes in the rehabilitation of patients with multiple sclerosis (MS) has been a controversial issue for many years. During the last decade, however, evidence from a number of studies has suggested that exercise is a safe and efficient way to induce improvements...

  10. Urinary amino acid analysis: a comparison of iTRAQ-LC-MS/MS, GC-MS, and amino acid analyzer.

    Science.gov (United States)

    Kaspar, Hannelore; Dettmer, Katja; Chan, Queenie; Daniels, Scott; Nimkar, Subodh; Daviglus, Martha L; Stamler, Jeremiah; Elliott, Paul; Oefner, Peter J

    2009-07-01

    Urinary amino acid analysis is typically done by cation-exchange chromatography followed by post-column derivatization with ninhydrin and UV detection. This method lacks throughput and specificity. Two recently introduced stable isotope ratio mass spectrometric methods promise to overcome those shortcomings. Using two blinded sets of urine replicates and a certified amino acid standard, we compared the precision and accuracy of gas chromatography/mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) of propyl chloroformate and iTRAQ derivatized amino acids, respectively, to conventional amino acid analysis. The GC-MS method builds on the direct derivatization of amino acids in diluted urine with propyl chloroformate, GC separation and mass spectrometric quantification of derivatives using stable isotope labeled standards. The LC-MS/MS method requires prior urinary protein precipitation followed by labeling of urinary and standard amino acids with iTRAQ tags containing different cleavable reporter ions distinguishable by MS/MS fragmentation. Means and standard deviations of percent technical error (%TE) computed for 20 amino acids determined by amino acid analyzer, GC-MS, and iTRAQ-LC-MS/MS analyses of 33 duplicate and triplicate urine specimens were 7.27+/-5.22, 21.18+/-10.94, and 18.34+/-14.67, respectively. Corresponding values for 13 amino acids determined in a second batch of 144 urine specimens measured in duplicate or triplicate were 8.39+/-5.35, 6.23+/-3.84, and 35.37+/-29.42. Both GC-MS and iTRAQ-LC-MS/MS are suited for high-throughput amino acid analysis, with the former offering at present higher reproducibility and completely automated sample pretreatment, while the latter covers more amino acids and related amines.

  11. Urinary Amino Acid Analysis: A Comparison of iTRAQ®-LC-MS/MS, GC-MS, and Amino Acid Analyzer

    Science.gov (United States)

    Kaspar, Hannelore; Dettmer, Katja; Chan, Queenie; Daniels, Scott; Nimkar, Subodh; Daviglus, Martha L.; Stamler, Jeremiah; Elliott, Paul; Oefner, Peter J.

    2009-01-01

    Urinary amino acid analysis is typically done by cation-exchange chromatography followed by post-column derivatization with ninhydrin and UV detection. This method lacks throughput and specificity. Two recently introduced stable isotope ratio mass spectrometric methods promise to overcome those shortcomings. Using two blinded sets of urine replicates and a certified amino acid standard, we compared the precision and accuracy of gas chromatography/mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) of propyl chloroformate and iTRAQ® derivatized amino acids, respectively, to conventional amino acid analysis. The GC-MS method builds on the direct derivatization of amino acids in diluted urine with propyl chloroformate, GC separation and mass spectrometric quantification of derivatives using stable isotope labeled standards. The LC-MS/MS method requires prior urinary protein precipitation followed by labeling of urinary and standard amino acids with iTRAQ® tags containing different cleavable reporter ions distinguishable by MS/MS fragmentation. Means and standard deviations of percent technical error (%TE) computed for 20 amino acids determined by amino acid analyzer, GC-MS, and iTRAQ®-LC-MS/MS analyses of 33 duplicate and triplicate urine specimens were 7.27±5.22, 21.18±10.94, and 18.34±14.67, respectively. Corresponding values for 13 amino acids determined in a second batch of 144 urine specimens measured in duplicate or triplicate were 8.39±5.35, 6.23±3.84, and 35.37±29.42. Both GC-MS and iTRAQ®-LC-MS/MS are suited for high-throughput amino acid analysis, with the former offering at present higher reproducibility and completely automated sample pretreatment, while the latter covers more amino acids and related amines. PMID:19481989

  12. The role of EBV in MS pathogenesis

    DEFF Research Database (Denmark)

    Christensen, Tove

    2006-01-01

    Environmental factors operate on a background of genetic susceptibility in the pathogenesis of MS. Human herpesviruses, notably Epstein-Barr virus (EBV), and human endogenous retroviruses are factors associated with MS. EBV association is found in epidemiological surveys where late EBV infection...... confers a higher risk of MS, and EBV reactivation also appears to be linked to disease activity in early MS. MS patients have elevated anti-EBV antibody responses, both in serum and cerebrospinal fluid. Molecular mimicry is found between certain EBV and myelin epitopes in the cell-mediated immune response....... EBV cannot stand alone as a causal factor of MS, but is likely to play an indirect role as an activator of the underlying disease process....

  13. Software ion scan functions in analysis of glycomic and lipidomic MS/MS datasets.

    Science.gov (United States)

    Haramija, Marko

    2018-03-01

    Hardware ion scan functions unique to tandem mass spectrometry (MS/MS) mode of data acquisition, such as precursor ion scan (PIS) and neutral loss scan (NLS), are important for selective extraction of key structural data from complex MS/MS spectra. However, their software counterparts, software ion scan (SIS) functions, are still not regularly available. Software ion scan functions can be easily coded for additional functionalities, such as software multiple precursor ion scan, software no ion scan, and software variable ion scan functions. These are often necessary, since they allow more efficient analysis of complex MS/MS datasets, often encountered in glycomics and lipidomics. Software ion scan functions can be easily coded by using modern script languages and can be independent of instrument manufacturer. Here we demonstrate the utility of SIS functions on a medium-size glycomic MS/MS dataset. Knowledge of sample properties, as well as of diagnostic and conditional diagnostic ions crucial for data analysis, was needed. Based on the tables constructed with the output data from the SIS functions performed, a detailed analysis of a complex MS/MS glycomic dataset could be carried out in a quick, accurate, and efficient manner. Glycomic research is progressing slowly, and with respect to the MS experiments, one of the key obstacles for moving forward is the lack of appropriate bioinformatic tools necessary for fast analysis of glycomic MS/MS datasets. Adding novel SIS functionalities to the glycomic MS/MS toolbox has a potential to significantly speed up the glycomic data analysis process. Similar tools are useful for analysis of lipidomic MS/MS datasets as well, as will be discussed briefly. Copyright © 2017 John Wiley & Sons, Ltd.

  14. An improved method of sample preparation on AnchorChip targets for MALDI-MS and MS/MS and its application in the liver proteome project

    DEFF Research Database (Denmark)

    Zhang, Xumin; Shi, Liang; Shu, Shaokung

    2007-01-01

    An improved method for sample preparation for MALDI-MS and MS/MS using AnchorChip targets is presented. The method, termed the SMW method (sample, matrix wash), results in better sensitivity for peptide mass fingerprinting as well as for sequencing by MS/MS than previously published methods. The ...

  15. Structure Elucidation of Unknown Metabolites in Metabolomics by Combined NMR and MS/MS Prediction.

    Science.gov (United States)

    Boiteau, Rene M; Hoyt, David W; Nicora, Carrie D; Kinmonth-Schultz, Hannah A; Ward, Joy K; Bingol, Kerem

    2018-01-17

    We introduce a cheminformatics approach that combines highly selective and orthogonal structure elucidation parameters; accurate mass, MS/MS (MS²), and NMR into a single analysis platform to accurately identify unknown metabolites in untargeted studies. The approach starts with an unknown LC-MS feature, and then combines the experimental MS/MS and NMR information of the unknown to effectively filter out the false positive candidate structures based on their predicted MS/MS and NMR spectra. We demonstrate the approach on a model mixture, and then we identify an uncatalogued secondary metabolite in Arabidopsis thaliana . The NMR/MS² approach is well suited to the discovery of new metabolites in plant extracts, microbes, soils, dissolved organic matter, food extracts, biofuels, and biomedical samples, facilitating the identification of metabolites that are not present in experimental NMR and MS metabolomics databases.

  16. Analytical Method Details (MS): SE53_MS03 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE53_MS03 CE-TOF/MS Agilent CE capillary electrophoresis system,Agilent G3250AA LC/...s were performed using an Agilent CE capillary electrophoresis system (Agilent Technologies, Waldbronn, Germ

  17. Progression in familial and nonfamilial MS

    NARCIS (Netherlands)

    Koch, Marcus; Uyttenboogaart, Maarten; Heerings, Marco; Heersema, Dorothea; Mostert, Jop; De Keyser, Jacques

    Objective To investigate whether the timing of secondary or primary progression is different between patients with familial and nonfamilial multiple sclerosis (MS). Methods Information on the family history of 313 patients with MS was taken from our prospective hospital-based database. We used

  18. MassSieve: Panning MS/MS peptide data for proteins

    OpenAIRE

    Slotta, Douglas J.; McFarland, Melinda A.; Markey, Sanford P.

    2010-01-01

    We present MassSieve, a Java-based platform for visualization and parsimony analysis of single and comparative LC-MS/MS database search engine results. The success of mass spectrometric peptide sequence assignment algorithms has led to the need for a tool to merge and evaluate the increasing data set sizes that result from LC-MS/MS-based shotgun proteomic experiments. MassSieve supports reports from multiple search engines with differing search characteristics, which can increase peptide sequ...

  19. Application of LC–MS/MS for quantitative analysis of glucocorticoids and stimulants in biological fluids

    OpenAIRE

    Haneef, Jamshed; Shaharyar, Mohammad; Husain, Asif; Rashid, Mohd; Mishra, Ravinesh; Parveen, Shama; Ahmed, Niyaz; Pal, Manoj; Kumar, Deepak

    2013-01-01

    Liquid chromatography tandem mass chromatography (LCâMS/MS) is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LCâMS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches (column packing materials, column length and mobile phase) as well as different acquisiti...

  20. Application of LC–MS/MS for quantitative analysis of glucocorticoids and stimulants in biological fluids

    OpenAIRE

    Haneef, Jamshed; Shaharyar, Mohammad; Husain, Asif; Rashid, Mohd; Mishra, Ravinesh; Parveen, Shama; Ahmed, Niyaz; Pal, Manoj; Kumar, Deepak

    2013-01-01

    Liquid chromatography tandem mass chromatography (LC–MS/MS) is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC–MS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches (column packing materials, column length and mobile phase) as well as different acquisiti...

  1. Ferro-based derivatizing agents for LC/MS an LC/EC/MS

    NARCIS (Netherlands)

    Seiwert, Bettina

    2007-01-01

    Within this thesis, the development and application of ferrocene-based derivatizing agents for LC/MS and LC/EC/MS is presented. The advantages of derivatization by ferrocenes are the similtaneous introduction of a mass tag and an electroactive group, which make them ideally suited for LC/MS and

  2. Metabolomics data normalization with EigenMS.

    Directory of Open Access Journals (Sweden)

    Yuliya V Karpievitch

    Full Text Available Liquid chromatography mass spectrometry has become one of the analytical platforms of choice for metabolomics studies. However, LC-MS metabolomics data can suffer from the effects of various systematic biases. These include batch effects, day-to-day variations in instrument performance, signal intensity loss due to time-dependent effects of the LC column performance, accumulation of contaminants in the MS ion source and MS sensitivity among others. In this study we aimed to test a singular value decomposition-based method, called EigenMS, for normalization of metabolomics data. We analyzed a clinical human dataset where LC-MS serum metabolomics data and physiological measurements were collected from thirty nine healthy subjects and forty with type 2 diabetes and applied EigenMS to detect and correct for any systematic bias. EigenMS works in several stages. First, EigenMS preserves the treatment group differences in the metabolomics data by estimating treatment effects with an ANOVA model (multiple fixed effects can be estimated. Singular value decomposition of the residuals matrix is then used to determine bias trends in the data. The number of bias trends is then estimated via a permutation test and the effects of the bias trends are eliminated. EigenMS removed bias of unknown complexity from the LC-MS metabolomics data, allowing for increased sensitivity in differential analysis. Moreover, normalized samples better correlated with both other normalized samples and corresponding physiological data, such as blood glucose level, glycated haemoglobin, exercise central augmentation pressure normalized to heart rate of 75, and total cholesterol. We were able to report 2578 discriminatory metabolite peaks in the normalized data (p<0.05 as compared to only 1840 metabolite signals in the raw data. Our results support the use of singular value decomposition-based normalization for metabolomics data.

  3. EPA CRL MS014: Analysis of Aldicarb, Bromadiolone, Carbofuran, Oxamyl and Methomyl in Water by Multiple Reaction Monitoring Liquid Chromatography / Tandem Mass Spectrometry (LC/MS/MS)

    Science.gov (United States)

    Method MS014 describes procedures for solvent extraction of aldicarb, bromadiolone, carbofuran, oxamyl and methomyl from water samples, followed by analysis using liquid chromatography tandem mass spectrometry (LC-MS-MS).

  4. Venocentric lesions: an MRI marker of MS?

    Directory of Open Access Journals (Sweden)

    Matthew P. Quinn

    2013-07-01

    Full Text Available From the earliest descriptions of MS, the venocentric characteristic of plaques was noted. Recently, numerous MRI studies have proposed this finding as a prospective biomarker for MS, which might aid in differentiating MS from other diseases with similar MRI findings. High field MRI studies have shown that penetrating veins can be detected in most MS lesions using T2* weighted or susceptibility weighted imaging. Future studies must address the feasibility of imaging such veins in a clinically practical context. The specificity of this biomarker has been studied only in a limited capacity. Results in microangiopathic lesions are conflicting, whereas asymptomatic white matter hyperintensities as well as lesions of NMO are less frequently venocentric compared to MS plaques. Prospective studies have shown that the presence of venocentric lesions at an early clinical presentation is highly predictive of future MS diagnosis. This is very promising, but work remains to be done to confirm or exclude lesions of common MS mimics, such as ADEM, as venocentric. A number of technical challenges must be addressed before the introduction of this technique as a complementary tool in current diagnostic procedures.

  5. The neurophysiologist perspective into MS plasticity

    Directory of Open Access Journals (Sweden)

    Elise eHoudayer

    2015-09-01

    Full Text Available Multiple sclerosis (MS is a frequent, highly debilitating inflammatory demyelinating disease, starting to manifest in early adulthood and presenting a wide variety of symptoms which are often resistant to pharmacological treatments. Cortical dysfunctions have been demonstrated to be key components of MS condition, and plasticity of the corticospinal motor system is highly involved in major MS symptoms, such as fatigue, spasticity or pain. Cortical dysfunction in MS can be studied with neurophysiological tools such as electroencephalography (EEG and related techniques (evoked potentials – EPs or transcranial magnetic stimulation (TMS. These techniques are now widely used to provide essential elements of MS diagnosis and can also be used to modulate plasticity. Indeed the recent development of non-invasive brain stimulation (NIBS techniques able to induce cortical plasticity, such as repetitive TMS or transcranial direct current stimulation (tDCS, has brought promising results as add-on treatments.In this review we will focus on the use of these tools (EEG, TMS to study plasticity in MS and on the major techniques used to modulate plasticity in MS.

  6. The Neurophysiologist Perspective into MS Plasticity.

    Science.gov (United States)

    Houdayer, Elise; Comi, Giancarlo; Leocani, Letizia

    2015-01-01

    Multiple sclerosis (MS) is a frequent, highly debilitating inflammatory demyelinating disease, starting to manifest in early adulthood and presenting a wide variety of symptoms, which are often resistant to pharmacological treatments. Cortical dysfunctions have been demonstrated to be key components of MS condition, and plasticity of the corticospinal motor system is highly involved in major MS symptoms, such as fatigue, spasticity, or pain. Cortical dysfunction in MS can be studied with neurophysiological tools, such as electroencephalography (EEG) and related techniques (evoked potentials) or transcranial magnetic stimulation (TMS). These techniques are now widely used to provide essential elements of MS diagnosis and can also be used to modulate plasticity. Indeed, the recent development of non-invasive brain stimulation techniques able to induce cortical plasticity, such as repetitive TMS or transcranial direct current stimulation, has brought promising results as add-on treatments. In this review, we will focus on the use of these tools (EEG and TMS) to study plasticity in MS and on the major techniques used to modulate plasticity in MS.

  7. Analysis of poly-beta-hydroxybutyrate in environmental samples by GC-MS/MS.

    Science.gov (United States)

    Elhottová, D; Tríska, J; Petersen, S O; Santrůcková, H

    2000-05-01

    Application of gas chromatography-mass spectrometry (GC-MS) can significantly improve trace analyses of compounds in complex matrices from natural environments compared to gas chromatography only. A GC-MS/MS technique for determination of poly-beta-hydroxybutyrate (PHB), a bacterial storage compound, has been developed and used for analysis of two soils stored for up to 319 d, fresh samples of sewage sludge, as well as a pure culture of Bacillus megaterium. Specific derivatization of beta-hydroxybutyrate (3-OH C4:0) PHB monomer units by N-tert-butyl-dimethylsilyl-N-methyltrifluoracetamide (MTBSTFA) improved chromatographic and mass spectrometric properties of the analyte. The diagnostic fragmentation scheme of the derivates tert-butyldimethylsilyl ester and ether of beta-hydroxybutyric acid (MTBSTFA-HB) essential for the PHB identification was shown. The ion trap MS was used, therefore the scan gave the best sensitivity and with MS/MS the noise decreased, so the S/N was better and also with second fragmentation the amount of ions increased compared to SIM. The detection limit for MTBSTFA-HB by GC-MS/MS was about 10(-13) g microL(-1) of injected volume, while by GC (FID) and GC-MS (scan) it was around 10(-10) g microL(-1) of injected volume. Sensitivity of GC-MS/MS measurements of PHB in arable soil and activated sludge samples was down to 10 pg of PHB g(-1) dry matter. Comparison of MTBSTFA-HB detection in natural soil sample by GC (FID), GC-MS (scan) and by GC-MS/MS demonstrated potentials and limitations of the individual measurement techniques.

  8. In Vivo Metabolism Study of Xiamenmycin A in Mouse Plasma by UPLC-QTOF-MS and LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Feng Lei

    2015-01-01

    Full Text Available Xiamenmycin A is an antifibrotic leading compound with a benzopyran skeleton that is isolated from mangrove-derived Streptomyces xiamenensis. As a promising small molecule for fibrotic diseases, less information is known about its metabolic characteristics in vivo. In this study, the time-course of xiamenmycin A in mouse plasma was investigated by relative quantification. After two types of administration of xiamenmycin A at a single dose of 10 mg/kg, the plasma concentrations were measured quantitatively by LC-MS/MS. The dynamic changes in the xiamenmycin A concentration showed rapid absorption and quick elimination in plasma post-administration. Four metabolites (M1–M4 were identified in blood by UPLC-QTOF-MS, and xiamenmycin B (M3 is the principal metabolite in vivo, as verified by comparison of the authentic standard sample. The structures of other metabolites were identified based on the characteristics of their MS and MS/MS data. The newly identified metabolites are useful for understanding the metabolism of xiamenmycin A in vivo, aiming at the development of an anti-fibrotic drug candidate for the therapeutic treatment of excessive fibrotic diseases.

  9. Automated protein identification by the combination of MALDI MS and MS/MS spectra from different instruments.

    Science.gov (United States)

    Levander, Fredrik; James, Peter

    2005-01-01

    The identification of proteins separated on two-dimensional gels is most commonly performed by trypsin digestion and subsequent matrix-assisted laser desorption ionization (MALDI) with time-of-flight (TOF). Recently, atmospheric pressure (AP) MALDI coupled to an ion trap (IT) has emerged as a convenient method to obtain tandem mass spectra (MS/MS) from samples on MALDI target plates. In the present work, we investigated the feasibility of using the two methodologies in line as a standard method for protein identification. In this setup, the high mass accuracy MALDI-TOF spectra are used to calibrate the peptide precursor masses in the lower mass accuracy AP-MALDI-IT MS/MS spectra. Several software tools were developed to automate the analysis process. Two sets of MALDI samples, consisting of 142 and 421 gel spots, respectively, were analyzed in a highly automated manner. In the first set, the protein identification rate increased from 61% for MALDI-TOF only to 85% for MALDI-TOF combined with AP-MALDI-IT. In the second data set the increase in protein identification rate was from 44% to 58%. AP-MALDI-IT MS/MS spectra were in general less effective than the MALDI-TOF spectra for protein identification, but the combination of the two methods clearly enhanced the confidence in protein identification.

  10. Method-MS, final report 2010

    DEFF Research Database (Denmark)

    Skipperud, Lindis; Popic, Jelena M.; Roos, Per

    Radiometric determination methods, such as alpha spectrometry require long counting times when low activities are to be determined. Mass spectrometric techniques as Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Thermal Ionisation Mass Spectrometry (TIMS) and Accelerator Mass Spectrometry...

  11. Significance of MRI Perivascular Spaces in MS

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2008-10-01

    Full Text Available The role of perivascular Virchow-Robin spaces was investigated in 45 multiple sclerosis (MS patients and 30 healthy controls, in a study at Charite-Universitaetsmedizin Berlin, and Goethe University, Frankfurt.

  12. Simultaneous analysis of 17 diuretics in dietary supplements by HPLC and LC-MS/MS.

    Science.gov (United States)

    Woo, H; Kim, J W; Han, K M; Lee, J H; Hwang, I S; Lee, J H; Kim, J; Kweon, S J; Cho, S; Chae, K R; Han, S Y; Kim, J

    2013-01-01

    In order to test health foods for illegally added diuretics for weight loss, we developed simple, rapid, selective, and sensitive methods using HPLC and LC-MS/MS for the simultaneous analysis of 17 diuretics in dietary supplements. HPLC conditions were set with a Capcell-pak C18, using a mobile phase consisting of gradient conditions, UV detection at 254 nm and validated for linearity (r(2)> 0.999), precision (CV ≤ 3%), recoveries (90.4-102.8%) and reproducibility. Identification and quantification of 17 diuretics were accomplished by ion-spray LC-MS/MS using multiple reaction monitoring (MRM). The chromatographic separation was carried out under the reversed-phase mechanism on an HSS-T3 column. The LC-MS/MS method was validated for linearity (r(2)> 0.99) and precision (CV Diuretics were not detected in all samples. Extraction recovery was also investigated and the extraction recoveries in different formulations were from 88% to 110% and from 81% to 116% using HPLC and LC-MS/MS, respectively. There was no significant difference in recoveries in the type of dietary supplements. Based on this result, the developed methods to monitor illegal drug adulterations in dietary supplements using HPLC and LC-MS/MS are simple, fast and reliable. Therefore, it is applicable to routine drug-adulteration screening.

  13. Multi-Segment Direct Inject nano-ESI-LTQ-FT-ICR-MS/MS For Protein Identification

    Directory of Open Access Journals (Sweden)

    Neal Rachel E

    2011-07-01

    Full Text Available Abstract Reversed phase high performance liquid chromatography (HPLC interfaced to electrospray tandem mass spectrometry (MS/MS is commonly used for the identification of peptides from proteolytically cleaved proteins embedded in a polyacrylamide gel matrix as well as for metabolomics screening. HPLC separations are time consuming (30-60 min average, costly (columns and mobile phase reagents, and carry the risk of column carry over between samples. The use of a chip-based nano-ESI platform (Advion NanoMate based on replaceable nano-tips for sample introduction eliminates sample cross-contamination, provides unchanging sample matrix, and enhances spray stability with attendant increases in reproducibility. Recent papers have established direct infusion nano-ESI-MS/MS utilizing the NanoMate for protein identification of gel spots based on full range MS scans with data dependent MS/MS. In a full range scan, discontinuous ion suppression due to sample matrix can impair identification of putative mass features of interest in both the proteomic and metabolomic workflows. In the current study, an extension of an established direct inject nano-ESI-MS/MS method is described that utilizes the mass filtering capability of an ion-trap for ion packet separation into four narrow mass ranges (50 amu overlap with segment specific dynamic data dependent peak inclusion for MS/MS fragmentation (total acquisition time of 3 minutes. Comparison of this method with a more traditional nanoLC-MS/MS based protocol utilizing solvent/sample stream splitting to achieve nanoflow demonstrated comparable results for protein identification from polyacrylamide gel matrices. The advantages of this method include full automation, lack of cross-contamination, low cost, and high throughput.

  14. Information-dependent acquisition-mediated LC-MS/MS screening procedure with semiquantitative potential.

    Science.gov (United States)

    Decaestecker, Tineke N; Vande Casteele, Sofie R; Wallemacq, Pierre E; Van Peteghem, Carlos H; Defore, Dieter L; Van Bocxlaer, Jan F

    2004-11-01

    The development of a LC-MS/MS general unknown screening procedure for toxicologically relevant substances in blood samples by means of information-dependent acquisition on a Q-TOF is reported. IDA is an artificial intelligence-based product ion scan mode providing automatic "on-the-fly" MS to MS/MS switching. By performing information-dependent scanning at two different fragmentation energies, two collision-induced dissociation product ion spectra for each of the detected compounds are generated. As such, information-rich MS/MS spectra are obtained from precursor ions not known beforehand. In addition, limitation of the MS/MS acquisition time to an acceptable minimum resulted in an almost instantaneous switch back to the MS mode. As such, this approach provided MS chromatograms that still could be of use for semiquantitative purposes. Since the switching intensity threshold, unequivocally related to the background noise, proved a critical parameter, the solid-phase extraction procedure, the liquid chromatographic conditions, and the mass spectrometric parameters all were optimized to the advantage of information-dependent acquisition. Finally, the screening procedure we developed was benchmarked, on one hand, qualitatively against the results obtained from traditional GUS approaches in a number of routine toxicological laboratories (20 samples) and, on the other hand, quantitatively with respect to its potential against established LC-MS/MS methods (7 samples). The procedure performed very well from a qualitative point of view; almost all of the drugs detected by the conventional techniques were identified, as well as additional drugs that were not previously reported. The procedure proved well-suited for an initial semiquantitative assessment, as is customary in, for example, forensic toxicology before accurate intoxication levels are determined using targeted analytical analyses.

  15. Sulphur fertilization influences the sulphur species composition in Allium sativum: sulphomics using HPLC-ICPMS/MS-ESI-MS/MS.

    Science.gov (United States)

    Raab, Andrea; Ronzan, Marilena; Feldmann, Joerg

    2017-10-18

    Garlic (A. sativum) contains a large number of small sulphur (S)-containing metabolites, which are important for its taste and smell and vary with A. sativum variety and growth conditions. This study was designed to investigate the influence of different sulphur-fertilization regimes on low molecular weight S-species by attempting the first sulphur mass balance in A. sativum roots and bulbs using HPLC-ICPMS/MS-ESI-MS/MS. Species unspecific quantification of acid soluble S-containing metabolites was achieved using HPLC-ICP-MS/MS. For identification of the compounds, high resolution ESI-MS (Orbitrap LTQ and q-TOF) was used. The plants contained up to 54 separated sulphur-containing compounds, which constitute about 80% of the total sulphur present in A. sativum. The roots and bulbs of A. sativum contained the same compounds, but not necessarily the same amounts and proportions. The S-containing metabolites in the roots reacted more sensitively to manipulations of sulphur fertilization than those compounds in the bulbs. In addition to known compounds (e.g. γ-glutamyl-S-1-propenylcysteine) we were able to identify and partially quantify 31 compounds. Three as yet undescribed S-containing compounds were also identified and quantified for the first time. Putative structures were assigned to the oxidised forms of S-1-propenylmercaptoglutathione, S-2-propenylmercaptoglutathione, S-allyl/propenyl-containing PC-2 and 2-amino-3-[(2-carboxypropyl)sulfanyl]propanoic acid. The parallel use of ICP-MS/MS as a sulphur-specific detector and ESI-MS as a molecular detector simplifies the identification and quantification of sulphur containing metabolites without species specific standards. This non-target analysis approach enables a mass balance approach and identifies the occurrence of the so far unidentified organosulphur compounds. The experiments showed that the sulphur-fertilization regime does not influence sulphur-speciation, but the concentration of some S

  16. Dansyl-peptides matrix-assisted laser desorption/ionization mass spectrometric (MALDI-MS) and tandem mass spectrometric (MS/MS) features improve the liquid chromatography/MALDI-MS/MS analysis of the proteome.

    Science.gov (United States)

    Chiappetta, Giovanni; Ndiaye, Sega; Demey, Emmanuelle; Haddad, Iman; Marino, Gennaro; Amoresano, Angela; Vinh, Joëlle

    2010-10-30

    Peptide tagging is a useful tool to improve matrix-assisted laser desorption/ionization tandem mass spectrometric (MALDI-MS/MS) analysis. We present a new application of the use of the dansyl chloride (DNS-Cl). DNS-Cl is a specific primary amine reagent widely used in protein biochemistry. It adds a fluorescent dimethylaminonaphthalene moiety to the molecule. The evaluation of MALDI-MS and MS/MS analyses of dansylated peptides shows that dansylation raises the ionization efficiency of the most hydrophilic species compared with the most hydrophobic ones. Consequently, higher Mascot scores and protein sequence coverage are obtained by combining MS and MS/MS data of native and tagged samples. The N-terminal DNS-Cl sulfonation improves the peptide fragmentation and promotes the generation of b-fragments allowing better peptide sequencing. In addition, we set up a labeling protocol based on the microwave chemistry. Peptide dansylation proved to be a rapid and cheap method to improve the performance of liquid chromatography (LC)/MALDI-MS/MS analysis at the proteomic scale in terms of peptide detection and sequence coverage. Copyright © 2010 John Wiley & Sons, Ltd.

  17. LC-MS-MS identification of drug metabolites obtained by metalloporphyrin mediated oxidation

    Directory of Open Access Journals (Sweden)

    Maurin Andrea J. M.

    2003-01-01

    Full Text Available In this paper we report the application of liquid chromatography-mass spectrometry (LC-MS-MS to the identification of the products formed by oxidation of albendazole and disopyramide with metalloporphyrins in dichloroethane, using iodosylbenzene as an oxygen donor. Our results show that LC-MS-MS is a powerful tool to study the in vitro metabolism of drugs, allowing the identification of known and unknown metabolites. In addition, it was observed that the catalyst system used resulted in the formation of the same metabolites as obtained in vivo, although for disopyramide other products were also observed.

  18. Analytical Method Details (MS): SE52_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available stem and Waters Q-Tof Premier UPLC-QTOF-MS ESI Negative The eluates (3 μl) were subsequently subjected to metabolome...DS column (LC-ESI-Q-Tof/MS, HPLC: Waters Acquity UPLC system; MS: Waters Q-Tof Premier). The metabolome...d (Matsuda et al., 2009c, 2010a). Briefly, the metabolome data were obtained in the negative ion mode (m/z 1... the complex nature of the metabolome data. To construct MS2T libraries, the extracts of five ecotypes were

  19. Characterization, stoichiometry, and stability of salivary protein-tannin complexes by ESI-MS and ESI-MS/MS.

    Science.gov (United States)

    Canon, Francis; Paté, Franck; Meudec, Emmanuelle; Marlin, Thérèse; Cheynier, Véronique; Giuliani, Alexandre; Sarni-Manchado, Pascale

    2009-12-01

    Numerous protein-polyphenol interactions occur in biological and food domains particularly involving proline-rich proteins, which are representative of the intrinsically unstructured protein group (IUP). Noncovalent protein-ligand complexes are readily detected by electrospray ionization mass spectrometry (ESI-MS), which also gives access to ligand binding stoichiometry. Surprisingly, the study of interactions between polyphenolic molecules and proteins is still an area where ESI-MS has poorly benefited, whereas it has been extensively applied to the detection of noncovalent complexes. Electrospray ionization mass spectrometry has been applied to the detection and the characterization of the complexes formed between tannins and a human salivary proline-rich protein (PRP), namely IB5. The study of the complex stability was achieved by low-energy collision-induced dissociation (CID) measurements, which are commonly implemented using triple quadrupole, hybrid quadrupole time-of-flight, or ion trap instruments. Complexes composed of IB5 bound to a model polyphenol EgCG have been detected by ESI-MS and further analyzed by MS/MS. Mild ESI interface conditions allowed us to observe intact noncovalent PRP-tannin complexes with stoichiometries ranging from 1:1 to 1:5. Thus, ESI-MS shows its efficiency for (1) the study of PRP-tannin interactions, (2) the determination of stoichiometry, and (3) the study of complex stability. We were able to establish unambiguously both their stoichiometries and their overall subunit architecture via tandem mass spectrometry and solution disruption experiments. Our results prove that IB5.EgCG complexes are maintained intact in the gas phase.

  20. Metabolic profiling of roots of liquorice (Glycyrrhiza glabra) from different geographical areas by ESI/MS/MS and determination of major metabolites by LC-ESI/MS and LC-ESI/MS/MS.

    Science.gov (United States)

    Montoro, Paola; Maldini, Mariateresa; Russo, Mariateresa; Postorino, Santo; Piacente, Sonia; Pizza, Cosimo

    2011-02-20

    Liquid chromatography electrospray mass spectrometry (LC-ESI/MS) has been applied to the full characterization of saponins and phenolics in hydroalcoholic extracts of roots of liquorice (Glycyrrhiza glabra). Relative quantitative analyses of the samples with respect to the phenolic constituents and to a group of saponins related to glycyrrhizic acid were performed using LC-ESI/MS. For the saponin constituents, full scan LC-MS/MS fragmentation of the protonated (positive ion mode) or deprotonated (negative ion mode) molecular species generated diagnostic fragment ions that provided information concerning the triterpene skeleton and the number and nature of the substituents. On the basis of the specific fragmentation of glycyrrhizic acid, an LC-MS/MS method was developed in order to quantify the analyte in the liquorice root samples. Chinese G. glabra roots contained the highest levels of glycyrrhizic acid, followed by those from Italy (Calabria). Copyright © 2010 Elsevier B.V. All rights reserved.

  1. Analytical Method Details (MS): SE29_MS1 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available SE29_MS1 LC-FT-ICR-MS ESI positive method 1 Agilent1100 HPLC (Agilent), LTQ-FT (The... (100mg) are solved in 300uL 80% methanol solution. 20uL sample is injected into HPLC after 0.2um membrane filter treatment. HPLC

  2. Analytical Method Details (MS): SE2_MS3 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available 00.0-1500.0); 2: ITMS + c norm !corona !pi Dep MS/MS Most intense ion from (1)., Rejected mass=284.2000;300.2000;328.2000;344.2000;372.2000;388.2000;416.3000;432.3000;460.0000. ...

  3. Natural isotope correction of MS/MS measurements for metabolomics and (13)C fluxomics.

    Science.gov (United States)

    Niedenführ, Sebastian; ten Pierick, Angela; van Dam, Patricia T N; Suarez-Mendez, Camilo A; Nöh, Katharina; Wahl, S Aljoscha

    2016-05-01

    Fluxomics and metabolomics are crucial tools for metabolic engineering and biomedical analysis to determine the in vivo cellular state. Especially, the application of (13)C isotopes allows comprehensive insights into the functional operation of cellular metabolism. Compared to single MS, tandem mass spectrometry (MS/MS) provides more detailed and accurate measurements of the metabolite enrichment patterns (tandem mass isotopomers), increasing the accuracy of metabolite concentration measurements and metabolic flux estimation. MS-type data from isotope labeling experiments is biased by naturally occurring stable isotopes (C, H, N, O, etc.). In particular, GC-MS(/MS) requires derivatization for the usually non-volatile intracellular metabolites introducing additional natural isotopes leading to measurements that do not directly represent the carbon labeling distribution. To make full use of LC- and GC-MS/MS mass isotopomer measurements, the influence of natural isotopes has to be eliminated (corrected). Our correction approach is analyzed for the two most common applications; (13)C fluxomics and isotope dilution mass spectrometry (IDMS) based metabolomics. Natural isotopes can have an impact on the calculated flux distribution which strongly depends on the substrate labeling and the actual flux distribution. Second, we show that in IDMS based metabolomics natural isotopes lead to underestimated concentrations that can and should be corrected with a nonlinear calibration. Our simulations indicate that the correction for natural abundance in isotope based fluxomics and quantitative metabolomics is essential for correct data interpretation. © 2015 Wiley Periodicals, Inc.

  4. Dried blood spot analysis of creatinine with LC-MS/MS in addition to immunosuppressants analysis

    NARCIS (Netherlands)

    Koster, Remco A.; Greijdanus, Ben; Alffenaar, Jan-Willem C.; Touw, Daan J.

    In order to monitor creatinine levels or to adjust the dosage of renally excreted or nephrotoxic drugs, the analysis of creatinine in dried blood spots (DBS) could be a useful addition to DBS analysis. We developed a LC-MS/MS method for the analysis of creatinine in the same DBS extract that was

  5. Quantification of free and total sialic acid excretion by LC-MS/MS

    NARCIS (Netherlands)

    van der Ham, Maria; Prinsen, Berthil H. C. M. T.; Huijmans, Jan G. M.; Abeling, Nicolaas G. G. M.; Dorland, Bert; Berger, Ruud; de Koning, Tom J.; de Sain-van der Velden, Monique G. M.

    2007-01-01

    The main purpose for measuring urinary free sialic acid (FSA) is to diagnose sialic acid (SA) storage diseases. Elevated amounts of conjugated sialic acid (CSA) are observed in several diseases indicating the need to quantify CSA as well. A LC-MS/MS method for quantification of FSA and total sialic

  6. STS-48 MS Buchli and MS Gemar on MB SMS middeck during JSC training session

    Science.gov (United States)

    1991-01-01

    STS-48 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) James F. Buchli (left) and MS Charles D. Gemar listen to instructions while on the middeck of JSC's Motion Based (MB) Shuttle Mission Simulator (SMS). Buchli and Gemar are reviewing inflight procedures during this preflight familiarization session held in the Mission Simulation and Training Facility Bldg 5.

  7. Determination of chlormequat in pig serum and sow milk by LC-MS/MS

    DEFF Research Database (Denmark)

    Poulsen, Mette Erecius; Christensen, Hanne Bjerre; Sørensen, M.T.

    2007-01-01

    reproduction. Validation of the method was based on recovery tests at three spiking levels, determined as double determinations and repeated at least four times. Samples were extracted with methanol-water-acetic acid, centrifuged, filtrated and determined by LC-MS/MS. The mean recoveries were in the range 80...

  8. Determination of selected bisphenols, parabens and estrogens in human plasma using LC-MS/MS

    Czech Academy of Sciences Publication Activity Database

    Kolatorova Sosvorova, L.; Chlupacova, T.; Vitku, J.; Vlk, Martin; Heráček, J.; Stárka, L.; Šaman, David; Šimková, M.; Hampl, R.

    2017-01-01

    Roč. 174, NOV 1 (2017), s. 21-28 ISSN 0039-9140 Institutional support: RVO:61389030 ; RVO:61388963 Keywords : Alternative bisphenol * Bisphenol A * Bisphenol F * Endocrine disruptor * lc-ms/ms * Paraben Subject RIV: CC - Organic Chemistry OBOR OECD: Analytical chemistry; Organic chemistry (UOCHB-X) Impact factor: 4.162, year: 2016

  9. Fach(sprach)lichkeit und Verständlichkeit in Verträgen

    DEFF Research Database (Denmark)

    Larsen, Aase Voldgaard

    2010-01-01

    categories (“lexis” and “syntax”) and in a content related category (“references and intertextuality”). The results provide knowledge about LSP and linguistic features of legal language, more precisely of different types of contracts, i.e. language in use. They can be used for didactic purposes in teaching...... by the judge in case of a litigation between the parties. On the one hand tradition demands that LSP texts are unambiguous, exact, economical (Fluck 1996), which gives them some conventional linguistic features, usually considered to make the texts difficult, on the other hand there is a legal demand...... that contracts must be accessible to non-professionals who have less knowledge of genre and linguistic conventions, and this may entail that legal language is changed accordingly. I wish to show what kinds of differences might exist between contracts between professionals and contracts between professionals...

  10. Diagnosis and heterogeneity of MS in MRI

    International Nuclear Information System (INIS)

    Holst, B.; Fiehler, J.; Schippling, S.

    2008-01-01

    An efficient therapy of MS requires a quick and reliable diagnosis of the disease. MRI is the most leading paraclinical examination for MS diagnosis. Even though there is no pathognomic finding in MRI, there are MS characteristics with respect to morphology and localization. To exclude other neurological disorders and distinguish between different characteristics within MS, the use of contrast agent is advantageous. Postulated MRI criteria have been increasingly adjusted to the clinical routine and have become clearer, more sensitive, and more specific. Different imaging criteria will be introduced. In addition to the McDonald criteria of 2001 and 2005, new criteria will be presented in which the use of contrast agent is replaced by a second MRI and the dissemination in time and space is simplified. Different pathomechanisms which help to separate MS patients into subgroups are postulated. The diverse pathomechanisms also enable the development of new pharmaceuticals to manipulate the immunologic course in different stages. For varying therapy approaches, it is increasingly important to differentiate the heterogeneous appearance forms into subtypes. The two visible main components of the disorder in MRI are inflammation and neurodegeneration and are responsible for different clinical courses. Both are interdependent and independent of each other. We introduce a stratification which uses both components as a function of their different outcomes to compose subgroups. The previous challenge with respect to MRI was to support the diagnosis of MS via MRI criteria. A future problem will be the heterogeneity and classification of subgroups. This article gives an overview of both problems. (orig.)

  11. An in silico MS/MS library for automatic annotation of novel FAHFA lipids.

    Science.gov (United States)

    Ma, Yan; Kind, Tobias; Vaniya, Arpana; Gennity, Ingrid; Fahrmann, Johannes F; Fiehn, Oliver

    2015-01-01

    A new lipid class named 'fatty acid esters of hydroxyl fatty acids' (FAHFA) was recently discovered in mammalian adipose tissue and in blood plasma and some FAHFAs were found to be associated with type 2 diabetes. To facilitate the automatic annotation of FAHFAs in biological specimens, a tandem mass spectra (MS/MS) library is needed. Due to the limitation of the commercial available standard compounds, we proposed building an in silico MS/MS library to extend the coverage of molecules. We developed a computer-generated library with 3267 tandem mass spectra (MS/MS) for 1089 FAHFA species. FAHFA spectra were generated based on authentic standards with negative mode electrospray ionization and 10, 20, and 40 V collision induced dissociation at 4 spectra/s as used in in ultra-high performance liquid chromatography-QTOF mass spectrometry studies. However, positional information of the hydroxyl group is only obtained either at lower QTOF spectra acquisition rates of 1 spectrum/s or at the MS(3) level in ion trap instruments. Therefore, an additional set of 4290 fragment-rich MS/MS spectra was created to enable distinguishing positional FAHFA isomers. The library was generated based on ion fragmentations and ion intensities of FAHFA external reference standards, developing a heuristic model for fragmentation rules and extending these rules to large swaths of computer-generated structures of FAHFAs with varying chain lengths, degrees of unsaturation and hydroxyl group positions. Subsequently, we validated the new in silico library by discovering several new FAHFA species in egg yolk, showing that this library enables high-throughput screening of FAHFA lipids in various biological matrices. The developed library and templates are freely available for commercial or noncommercial use at http://fiehnlab.ucdavis.edu/staff/yanma/fahfa-lipid-library. This in silico MS/MS library allows users to annotate FAHFAs from accurate mass tandem mass spectra in an easy and fast manner

  12. An impulse-driven liquid-droplet deposition interface for combining LC with MALDI MS and MS/MS.

    Science.gov (United States)

    Young, J Bryce; Li, Liang

    2006-03-01

    A simple and robust impulse-driven droplet deposition system was developed for off-line liquid chromatography matrix-assisted laser desorption ionization mass spectrometry (LC-MALDI MS). The system uses a solenoid operated with a pulsed voltage power supply to generate impulses that dislodge the hanging droplets from the LC outlet directly to a MALDI plate via a momentum transfer process. There is no contact between the LC outlet and the collection surface. The system is compatible with solvents of varying polarity and viscosity, and accommodates the use of hydrophobic and hydrophilic MALDI matrices. MALDI spots are produced on-line with the separation, and do not require further processing before MS analysis. It is shown that high quality MALDI spectra from 5 fmol of pyro-Glu-fibrinopeptide deposition after LC separation could be obtained using the device, indicating that there was no sample loss in the interface. To demonstrate the analytical performance of the system as a proteome analysis tool, a range of BSA digest concentrations covering about 3 orders of magnitude, from 5 fmol to 1 pmol, were analyzed by LC-MALDI quadrupole time-of-flight MS, yielding 6 and 57% amino acid sequence coverage, respectively. In addition, a complex protein mixture of an E. coli cell extract was tryptically digested and analyzed by LC-MALDI MS, resulting in the detection of a total of 409 unique peptides from 100 fractions of 15-s intervals.

  13. Dopamine, T cells and multiple sclerosis (MS).

    Science.gov (United States)

    Levite, Mia; Marino, Franca; Cosentino, Marco

    2017-05-01

    Dopamine is a key neurotransmitter that induces critical effects in the nervous system and in many peripheral organs, via 5 dopamine receptors (DRs): D1R-D5R. Dopamine also induces many direct and very potent effects on many DR-expressing immune cells, primarily T cells and dendritic cells. In this review, we focus only on dopamine receptors, effects and production in T cells. Dopamine by itself (at an optimal concentration of~0.1 nM) induces multiple function of resting normal human T cells, among them: T cell adhesion, chemotactic migration, homing, cytokine secretion and others. Interestingly, dopamine activates resting effector T cells (Teffs), but suppresses regulatory T cells (Tregs), and both effects lead eventually to Teff activation. Dopamine-induced effects on T cells are dynamic, context-sensitive and determined by the: T cell activation state, T cell type, DR type, and dopamine concentration. Dopamine itself, and also few dopaminergic molecules/ drugs that are in clinical use for cardiac, neurological and other non-immune indications, have direct effects on human T cells (summarized in this review). These dopaminergic drugs include: dopamine = intropin, L-DOPA, bromocriptine, pramipexole, pergolide, haloperidol, pimozide, and amantadine. Other dopaminergic drugs were not yet tested for their direct effects on T cells. Extensive evidence in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) show dopaminergic dysregulations in T cells in these diseases: D1-like DRs are decreased in Teffs of MS patients, and dopamine does not affect these cells. In contrast, D1-like DRs are increased in Tregs of MS patients, possibly causing functional Treg impairment in MS. Treatment of MS patients with interferon β (IFN-β) increases D1-like DRs and decreases D2-like DRs in Teffs, decreases D1-like DRs in Tregs, and most important: restores responsiveness of patient's Teffs to dopamine. DR agonists and antagonists confer some benefits in

  14. Quality evaluation of LC-MS/MS-based E. coli H antigen typing (MS-H) through label-free quantitative data analysis in a clinical sample setup.

    Science.gov (United States)

    Cheng, Keding; Sloan, Angela; McCorrister, Stuart; Peterson, Lorea; Chui, Huixia; Drebot, Mike; Nadon, Celine; Knox, J David; Wang, Gehua

    2014-12-01

    The need for rapid and accurate H typing is evident during Escherichia coli outbreak situations. This study explores the transition of MS-H, a method originally developed for rapid H antigen typing of E. coli using LC-MS/MS of flagella digest of reference strains and some clinical strains, to E. coli isolates in clinical scenario through quantitative analysis and method validation. Motile and nonmotile strains were examined in batches to simulate clinical sample scenario. Various LC-MS/MS batch run procedures and MS-H typing rules were compared and summarized through quantitative analysis of MS-H data output for a standard method development. Label-free quantitative data analysis of MS-H typing was proven very useful for examining the quality of MS-H result and the effects of some sample carryovers from motile E. coli isolates. Based on this, a refined procedure and protein identification rule specific for clinical MS-H typing was established and validated. With LC-MS/MS batch run procedure and database search parameter unique for E. coli MS-H typing, the standard procedure maintained high accuracy and specificity in clinical situations, and its potential to be used in a clinical setting was clearly established. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. siMS Score: Simple Method for Quantifying Metabolic Syndrome

    OpenAIRE

    Soldatovic, Ivan; Vukovic, Rade; Culafic, Djordje; Gajic, Milan; Dimitrijevic-Sreckovic, Vesna

    2016-01-01

    Objective To evaluate siMS score and siMS risk score, novel continuous metabolic syndrome scores as methods for quantification of metabolic status and risk. Materials and Methods Developed siMS score was calculated using formula: siMS score = 2*Waist/Height + Gly/5.6 + Tg/1.7 + TAsystolic/130?HDL/1.02 or 1.28 (for male or female subjects, respectively). siMS risk score was calculated using formula: siMS risk score = siMS score * age/45 or 50 (for male or female subjects, respectively) * famil...

  16. 2013 NRCS-USGS Lidar: Lauderdale (MS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME:NRCS LAUDERDALE MS 0.7M NPS LIDAR. LiDAR Data Acquisition and Processing Production Task. USGS Contract No. G10PC00057. Task Order No. G12PD000125 Woolpert...

  17. 2014 USGS/NRCS Lidar: Central MS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME: USGS-NRCS Laurel MS 0.7m NPS LIDAR Lidar Data Acquisition and Processing Production Task USGS Contract No. G10PC00057 Task Order No. G13PD01086 Woolpert...

  18. Interpretation of MS ISO/ IEC 17020

    International Nuclear Information System (INIS)

    Mohamad Pauzi Ismail

    2012-01-01

    MS ISO/ IEC 17020 is an international standard which adopted by Malaysian Standard states the requirement criteria for inspection bodies. The author involved in the NDT technical assessment to several NDT companies in Malaysia. The experience in performing NDT assessment activity is explained and discussed. (author)

  19. Retinoid quantification by HPLC/MS(n)

    Science.gov (United States)

    McCaffery, Peter; Evans, James; Koul, Omanand; Volpert, Amy; Reid, Kevin; Ullman, M. David

    2002-01-01

    Retinoic acid (RA) mediates most of the biological effects of vitamin A that are essential for vertebrate survival. It acts through binding to receptors that belong to the nuclear receptor transcription factor superfamily (Mangelsdorf et al. 1994). It is also a highly potent vertebrate teratogen. To determine the function and effects of endogenous and exogenous RA, it is important to have a highly specific, sensitive, accurate, and precise analytical procedure. Current analyses of RA and other retinoids are labor intensive, of poor sensitivity, have limited specificity, or require compatibility with RA reporter cell lines (Chen et al. 1995. BIOCHEM: Pharmacol. 50: 1257-1264; Creech Kraft et al. 1994. BIOCHEM: J. 301: 111-119; Lanvers et al. 1996. J. Chromatogr. B Biomed. Appl. 685: 233-240; Maden et al. 1998. DEVELOPMENT: 125: 4133-4144; Wagner et al. 1992. DEVELOPMENT: 116: 55-66). This paper describes an HPLC/mass spectrometry/mass spectrometry product ion scan (HPLC/MS(n)) procedure for the analysis of retinoids that employs atmospheric pressure chemical ionization MS. The retinoids are separated by normal-phase column chromatography with a linear hexane-isopropanol-dioxane gradient. Each retinoid is detected by a unique series of MS(n) functions set at optimal collision-induced dissociation energy (30% to 32%) for all MS(n) steps. The scan events are divided into three segments, based on HPLC elution order, to maximize the mass spectrometer duty cycle. The all-trans, 9-cis, and 13-cis RA isomers are separated, if desired, by an isocratic hexane-dioxane-isopropanol mobile phase. This paper describes an HPLC/MS(n) procedure possessing high sensitivity and specificity for retinoids.

  20. Improved LC-MS/MS method for the quantification of hepcidin-25 in clinical samples.

    Science.gov (United States)

    Abbas, Ioana M; Hoffmann, Holger; Montes-Bayón, María; Weller, Michael G

    2018-06-01

    Mass spectrometry-based methods play a crucial role in the quantification of the main iron metabolism regulator hepcidin by singling out the bioactive 25-residue peptide from the other naturally occurring N-truncated isoforms (hepcidin-20, -22, -24), which seem to be inactive in iron homeostasis. However, several difficulties arise in the MS analysis of hepcidin due to the "sticky" character of the peptide and the lack of suitable standards. Here, we propose the use of amino- and fluoro-silanized autosampler vials to reduce hepcidin interaction to laboratory glassware surfaces after testing several types of vials for the preparation of stock solutions and serum samples for isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS). Furthermore, we have investigated two sample preparation strategies and two chromatographic separation conditions with the aim of developing a LC-MS/MS method for the sensitive and reliable quantification of hepcidin-25 in serum samples. A chromatographic separation based on usual acidic mobile phases was compared with a novel approach involving the separation of hepcidin-25 with solvents at high pH containing 0.1% of ammonia. Both methods were applied to clinical samples in an intra-laboratory comparison of two LC-MS/MS methods using the same hepcidin-25 calibrators with good correlation of the results. Finally, we recommend a LC-MS/MS-based quantification method with a dynamic range of 0.5-40 μg/L for the assessment of hepcidin-25 in human serum that uses TFA-based mobile phases and silanized glass vials. Graphical abstract Structure of hepcidin-25 (Protein Data Bank, PDB ID 2KEF).

  1. Diet-induced perturbation of the rat liver mitochondrial acetylome studied by quantitative (iTRAQ) LC-MS/MS

    DEFF Research Database (Denmark)

    León, Ileana R.; Schwämmle, Veit; Williamson, James

    described3. Quantitation by MS/MS was achieved by using iTRAQ 8-Plex reagents (Life Technologies). LC-MS/MS analyses were performed using an Easy-nLC (Proxeon/ThermoFisher) fitted with an in-house made 17 cm C18 column that was interfaced to an LTQ-OrbiTrap XL instrument (ThermoFisher). Data analysis...

  2. ESI MS/MS Study of Calix[4]arene Derivatives and their Metal Complexes

    OpenAIRE

    Benković, Tomislav; Tomišić, Vladislav; Frkanec, Leo; Galić, Nives

    2012-01-01

    The peptidocalixarenes 1–3 bearing tryptophan, phenylglycine and leucil units at the lower rim and their complexes with alkali-metal (Li+, Na+, K+, Rb+, Cs+) and selected lanthanide cations (La3+, Ce3+, Eu3+, Yb3+) were analyzed by ESI MS. The influences of the solvent (acetonitrile, methanol, addition of formic acid or sodium acetate) and the calixarene:cation molar ratio on signal intensities were investigated. Comprehensive MS/MS analyses were performed of all singly and doubly charged ion...

  3. MsLDR-creator: a web service to design msLDR assays.

    Science.gov (United States)

    Bormann, Felix; Dahl, Andreas; Sers, Christine

    2012-03-01

    MsLDR-creator is a free web service to design assays for the new DNA methylation detection method msLDR. The service provides the user with all necessary information about the oligonucleotides required for the measurement of a given CpG within a sequence of interest. The parameters are calculated by the nearest neighbour approach to achieve optimal behaviour during the experimental procedure. In addition, to guarantee a good start using msLDR, further information, like protocols and hints and tricks, are provided.

  4. Factors Associated with Neurologists' Provision of MS Patient Care

    Science.gov (United States)

    Halpern, Michael T.; Teixeira-Poit, Stephanie M.; Kane, Heather; Frost, Corey; Keating, Michael; Olmsted, Murrey

    2014-01-01

    Neurologists are central to providing quality care for individuals with MS. However, neurologist shortages may restrict access to care for MS patients. To examine factors influencing neurologists' provision of MS care, we surveyed 1,700 US neurologists to assess demographic/practice characteristics, training, and attitudes toward MS care. The study population consisted of 573 respondents: 87 (15.2%) MS subspecialists and 486 (84.8%) “other neurologists,” including subspecialists in other neurology areas (i.e., non-MS) and general neurologists. MS subspecialists indicating they “enjoy interacting with MS patients” had a significantly greater rate of MS patients seen per week. In separate analyses of the “other neurologists” group, the rate of MS patients seen was lower among neurologists in university-based groups or those practicing in major cities; female neurologists; and neurologists who indicated lack of sufficient knowledge regarding MS patient care. Rates of MS patients seen were significantly greater for other neurologists who agreed that MS care involved “ability to improve patient outcomes and quality of life”; “dynamic area with evolving treatment options”; and “enjoy interacting with MS patients.” Understanding factors influencing MS patient care by neurologists and developing policies for appropriate access to care is critical for optimal outcomes among this population. PMID:24949203

  5. Factors Associated with Neurologists’ Provision of MS Patient Care

    Directory of Open Access Journals (Sweden)

    Michael T. Halpern

    2014-01-01

    Full Text Available Neurologists are central to providing quality care for individuals with MS. However, neurologist shortages may restrict access to care for MS patients. To examine factors influencing neurologists’ provision of MS care, we surveyed 1,700 US neurologists to assess demographic/practice characteristics, training, and attitudes toward MS care. The study population consisted of 573 respondents: 87 (15.2% MS subspecialists and 486 (84.8% “other neurologists,” including subspecialists in other neurology areas (i.e., non-MS and general neurologists. MS subspecialists indicating they “enjoy interacting with MS patients” had a significantly greater rate of MS patients seen per week. In separate analyses of the “other neurologists” group, the rate of MS patients seen was lower among neurologists in university-based groups or those practicing in major cities; female neurologists; and neurologists who indicated lack of sufficient knowledge regarding MS patient care. Rates of MS patients seen were significantly greater for other neurologists who agreed that MS care involved “ability to improve patient outcomes and quality of life”; “dynamic area with evolving treatment options”; and “enjoy interacting with MS patients.” Understanding factors influencing MS patient care by neurologists and developing policies for appropriate access to care is critical for optimal outcomes among this population.

  6. Quantitative Determination of Perfluorochemicals and Fluorotelomer Alcohols in Plants from Biosolid-Amended Fields using LC/MS/MS and GC/MS

    Science.gov (United States)

    Analytical methods for determining perfluorochemicals (PFCs) and fluorotelomer alcohols (FTOHs) in plants using liquid chromatography/tandem mass spectrometry (LC/MS/MS) and gas chromatography/mass spectrometry (GC/MS) were developed, and applied to quantify a suite of analytes i...

  7. Urinary Amino Acid Analysis: A Comparison of iTRAQ®-LC-MS/MS, GC-MS, and Amino Acid Analyzer

    OpenAIRE

    Kaspar, Hannelore; Dettmer, Katja; Chan, Queenie; Daniels, Scott; Nimkar, Subodh; Daviglus, Martha L.; Stamler, Jeremiah; Elliott, Paul; Oefner, Peter J.

    2009-01-01

    Urinary amino acid analysis is typically done by cation-exchange chromatography followed by post-column derivatization with ninhydrin and UV detection. This method lacks throughput and specificity. Two recently introduced stable isotope ratio mass spectrometric methods promise to overcome those shortcomings. Using two blinded sets of urine replicates and a certified amino acid standard, we compared the precision and accuracy of gas chromatography/mass spectrometry (GC-MS) and liquid chromatog...

  8. Rapid Determination of Isomeric Benzoylpaeoniflorin and Benzoylalbiflorin in Rat Plasma by LC-MS/MS Method

    Directory of Open Access Journals (Sweden)

    Chuanqi Zhou

    2017-01-01

    Full Text Available Benzoylpaeoniflorin (BP is a potential therapeutic agent against oxidative stress related Alzheimer’s disease. In this study, a more rapid, selective, and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS method was developed to determine BP in rat plasma distinguishing with a monoterpene isomer, benzoylalbiflorin (BA. The method showed a linear response from 1 to 1000 ng/mL (r>0.9950. The precision of the interday and intraday ranged from 2.03 to 12.48% and the accuracy values ranged from −8.00 to 10.33%. Each running of the method could be finished in 4 minutes. The LC-MS/MS method was validated for specificity, linearity, precision, accuracy, recovery, and stability and was found to be acceptable for bioanalytical application. Finally, this fully validated method was successfully applied to a pharmacokinetic study in rats following oral administration.

  9. DBS-LC-MS/MS assay for caffeine: validation and neonatal application.

    Science.gov (United States)

    Bruschettini, Matteo; Barco, Sebastiano; Romantsik, Olga; Risso, Francesco; Gennai, Iulian; Chinea, Benito; Ramenghi, Luca A; Tripodi, Gino; Cangemi, Giuliana

    2016-09-01

    DBS might be an appropriate microsampling technique for therapeutic drug monitoring of caffeine in infants. Nevertheless, its application presents several issues that still limit its use. This paper describes a validated DBS-LC-MS/MS method for caffeine. The results of the method validation showed an hematocrit dependence. In the analysis of 96 paired plasma and DBS clinical samples, caffeine levels measured in DBS were statistically significantly lower than in plasma but the observed differences were independent from hematocrit. These results clearly showed the need for extensive validation with real-life samples for DBS-based methods. DBS-LC-MS/MS can be considered to be a good alternative to traditional methods for therapeutic drug monitoring or PK studies in preterm infants.

  10. Determination of drug residues by CLAR-MS/MS in animal tissues

    International Nuclear Information System (INIS)

    Brenes Jimenez, Jose Eduardo

    2009-01-01

    Produced food of animal origin, present the possibility of occurrence of any contact with substances that have negative effects on the health of people who consume them. The use of drugs in veterinary medicine is one of the possible sources of such waste; so, the conditions for the analysis of some classes of antibiotics in animal tissues are based on the study. Costa Rica and the countries that are export destination, have regulation and programs for control before to be distributed in local markets, or post if it is received any complaint of pollution. The high resolution liquid chromatography coupled to mass spectrometers (CLAR-MS/MS) allows the analysis of analytes monitored, according to the specifications required by the legislation. The cases of two laboratories in Costa Rica are presented as the only ones who have the ability to perform the analysis of drug residues CLAR-MS/MS. (author) [es

  11. How much separation for LC-MS/MS quantitative bioanalysis of drugs and metabolites?

    Science.gov (United States)

    Tan, Aimin; Fanaras, John C

    2018-05-01

    LC-MS/MS has been the dominant analytical technology for quantitative bioanalysis of drugs and metabolites for more than two decades. Despite this, a very fundamental question like how much separation is required for LC-MS/MS quantitative bioanalysis of drugs and metabolites has not been adequately addressed. Some think that no or only very limited separation is necessary thanks to the unparalleled selectivity offered by tandem mass spectrometry. Others think that the more separation, the better, because of the potential detrimental impact of matrix effect (ion suppression or enhancement). Still others just use a rule-of-thumb approach by keeping the adjusted retention/capacity factor always between 2 and 5. The purpose of this article is to address this fundamental question through rational thinking together with various real case examples drawn from regulated bioanalytical laboratories. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Analytical Method Details (MS): SE59_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available argeted metabolomic analysis using LC-QTOF-MS and the metabolome data processing of alignment, de-isotoping, noise cutting, and normalization was conducted as previously described. ...

  13. MS+MS/MS

    Indian Academy of Sciences (India)

    2014-04-12

    /Pos. 130/F5. Instr./Gel Origin. AK139/T056. Process Status Analysis Succeeded. Plate [#] Name. [1] T056P10. Instrument Sample Name. Spectra. 9. Rank. Protein Name. Accession No. Protein. Protein MW Protein. Pep.

  14. The APEX Quantitative Proteomics Tool: Generating protein quantitation estimates from LC-MS/MS proteomics results

    Directory of Open Access Journals (Sweden)

    Saeed Alexander I

    2008-12-01

    Full Text Available Abstract Background Mass spectrometry (MS based label-free protein quantitation has mainly focused on analysis of ion peak heights and peptide spectral counts. Most analyses of tandem mass spectrometry (MS/MS data begin with an enzymatic digestion of a complex protein mixture to generate smaller peptides that can be separated and identified by an MS/MS instrument. Peptide spectral counting techniques attempt to quantify protein abundance by counting the number of detected tryptic peptides and their corresponding MS spectra. However, spectral counting is confounded by the fact that peptide physicochemical properties severely affect MS detection resulting in each peptide having a different detection probability. Lu et al. (2007 described a modified spectral counting technique, Absolute Protein Expression (APEX, which improves on basic spectral counting methods by including a correction factor for each protein (called Oi value that accounts for variable peptide detection by MS techniques. The technique uses machine learning classification to derive peptide detection probabilities that are used to predict the number of tryptic peptides expected to be detected for one molecule of a particular protein (Oi. This predicted spectral count is compared to the protein's observed MS total spectral count during APEX computation of protein abundances. Results The APEX Quantitative Proteomics Tool, introduced here, is a free open source Java application that supports the APEX protein quantitation technique. The APEX tool uses data from standard tandem mass spectrometry proteomics experiments and provides computational support for APEX protein abundance quantitation through a set of graphical user interfaces that partition thparameter controls for the various processing tasks. The tool also provides a Z-score analysis for identification of significant differential protein expression, a utility to assess APEX classifier performance via cross validation, and a

  15. Method Development and Validation for UHPLC-MS-MS Determination of Hop Prenylflavonoids in Human Serum

    OpenAIRE

    Yuan, Yang; Qiu, Xi; Nikolic, Dejan; Dahl, Jeffrey H.; van Breemen, Richard B.

    2012-01-01

    Hops (Humulus lupulus L.) are used in the brewing of beer, and hop extracts containing prenylated compounds such as xanthohumol and 8-prenylnaringenin are under investigation as dietary supplements for cancer chemoprevention and for the management of hot flashes in menopausal women. To facilitate clinical studies of hop safety and efficacy, a selective, sensitive, and fast ultra-high pressure liquid chromatography tandem mass spectrometry (UHPLC-MS-MS) method was developed and validated for t...

  16. Identification and Quantification of Several Mammalian Steroid Hormones in Plants by UPLC-MS/MS

    Czech Academy of Sciences Publication Activity Database

    Simerský, Radim; Novák, Ondřej; Morris, David; Pouzar, Vladimír; Strnad, Miroslav

    2009-01-01

    Roč. 28, č. 2 (2009), s. 125-136 ISSN 0721-7595 R&D Projects: GA AV ČR KAN200380801 Institutional research plan: CEZ:AV0Z50380511; CEZ:AV0Z40550506 Keywords : Ultra-performance liquid chromatography (UPLC) * Tandem mass spectrometry (MS/MS) * Immunoaffinity purification * Steroids * Plant extracts * Digitalis purpurea * Nicotiana tabacum * Inula helenium Subject RIV: EC - Immunology Impact factor: 2.438, year: 2009

  17. pDeep: Predicting MS/MS Spectra of Peptides with Deep Learning.

    Science.gov (United States)

    Zhou, Xie-Xuan; Zeng, Wen-Feng; Chi, Hao; Luo, Chunjie; Liu, Chao; Zhan, Jianfeng; He, Si-Min; Zhang, Zhifei

    2017-12-05

    In tandem mass spectrometry (MS/MS)-based proteomics, search engines rely on comparison between an experimental MS/MS spectrum and the theoretical spectra of the candidate peptides. Hence, accurate prediction of the theoretical spectra of peptides appears to be particularly important. Here, we present pDeep, a deep neural network-based model for the spectrum prediction of peptides. Using the bidirectional long short-term memory (BiLSTM), pDeep can predict higher-energy collisional dissociation, electron-transfer dissociation, and electron-transfer and higher-energy collision dissociation MS/MS spectra of peptides with >0.9 median Pearson correlation coefficients. Further, we showed that intermediate layer of the neural network could reveal physicochemical properties of amino acids, for example the similarities of fragmentation behaviors between amino acids. We also showed the potential of pDeep to distinguish extremely similar peptides (peptides that contain isobaric amino acids, for example, GG = N, AG = Q, or even I = L), which were very difficult to distinguish using traditional search engines.

  18. Investigation of enrofloxacin residues in broiler tissues using ELISA and LC-MS/MS.

    Science.gov (United States)

    Panzenhagen, Pedro Henrique N; Aguiar, Waldemir S; Gouvêa, Raquel; de Oliveira, Andréa M G; Barreto, Fabiano; Pereira, Virgínia L A; Aquino, Maria Helena C

    2016-01-01

    This study investigated the efficiency of an enrofloxacin ELISA test kit to detect the presence of enrofloxacin residues in broiler tissues compared with LC-MS/MS. Broiler tissues from 72 samples consisting of 60 breast muscle, six pools of livers (500 g each) and six pools of kidneys (500 g each) were obtained from six different slaughterhouses. Breast muscle from 10 carcasses and pools of livers and kidneys from approximately 200 carcasses of the same flock were collected from each slaughterhouse. ELISA and HPLC were used to identify and quantify the contamination of the samples with enrofloxacin. A total of 72% of the analysed samples contained enrofloxacin residues detected by the ELISA and 22.2% were detected by LC-MS/MS. The mean values of enrofloxacin contamination found in chicken breast by ELISA and HPLC were 8.63 and 12.25 μg kg(-1), respectively. None of the samples exceeded the maximum limit of 100 μg kg(-1) by both methods set by the European Union as well as the Brazilian Agriculture Ministry. All positive samples for enrofloxacin residues detected by LC-MS/MS were also positive by ELISA. These data confirm the efficiency of the ELISA test, and suggest its use as a screening method for enrofloxacin residues in poultry tissues due to its quick results, low price and ease of applicability.

  19. Relationship between plasma and salivary melatonin and cortisol investigated by LC-MS/MS.

    Science.gov (United States)

    van Faassen, Martijn; Bischoff, Rainer; Kema, Ido P

    2017-08-28

    Disturbance of the circadian rhythm has been associated with disease states, such as metabolic disorders, depression and cancer. Quantification of the circadian markers such as melatonin and cortisol critically depend on reliable and reproducible analytical methods. Previously, melatonin and cortisol were primarily analyzed separately, mainly using immunoassays. Here we describe the validation and application of a high-throughput liquid chromatography in combination with mass spectrometry (LC-MS/MS) method for the combined analysis of melatonin and cortisol in plasma and saliva. The LC-MS/MS method was validated according to international validation guidelines. We used this method to analyze total plasma, free plasma (as obtained by equilibrium dialysis) and saliva melatonin and cortisol in healthy adults. Validation results for plasma and saliva melatonin and cortisol were well within the international validation criteria. We observed no difference between saliva collected by passive drooling or Salivette. Moreover, we noted a significant difference in saliva vs. free plasma melatonin. We observed on average 36% (95% CI: 4%-60%) higher salivary melatonin levels in comparison to free plasma melatonin, suggestive of local production of melatonin in the salivary glands. The novel outcome of this study is probably due to the high precision of our LC-MS/MS assay. These outcomes illustrate the added value of accurate and sensitive mass spectrometry based methods for the quantification of neuroendocrine biomarkers.

  20. COMPARISON OF COMMERCIAL LC MS/MS COMPATIBLE DETERGENTS WITH SODIUM DEOXYCHOLATE FOR SHOTGUN PROTEOMICS

    Directory of Open Access Journals (Sweden)

    Caleb J. Porter

    2014-12-01

    Full Text Available In this study, we compared the performance of sodium deoxycholate (SDC with several commercially available LC MS/MS compatible detergents for digestion of complex proteomic mixtures. First, the parameters affecting in-solution digestion using SDC were investigated with a full factorial experimental design. Metrics explored were trypsin ratio, digestion time, and concentration of SDC. These parameters were not found to be statistically associated with total peptide identifications in the experimental space investigated. However, in terms of digestion efficiency, digestion time was highly significant (p = 0.0095 as determined by the percent of peptides identified with missed cleavages. The optimized protocol for peptide identification and throughput was used to compare the performance of SDC with various commercially available LC MS/MS compatible surfactants namely Invitrosol, RapiGest, and PPS Silent Surfactant. The detergents were found to be similar through comparisons of the total identified peptides and the hydrophobicity of recovered peptides. We found suitable recovery across a large range of SDC concentrations determined from a bicinchoninic acid (BCA assay. In a spike down experiment, no distinct differences in total number of peptide identifications were discovered when comparing PPS (Silent Surfactant and SDC for preparation of peptide samples derived from low protein amounts (< 20 µg. Combined, these results indicate that SDC is a cost effective alternative to other commonly used LC MS/MS compatible surfactants

  1. Economic costs associated with an MS relapse

    LENUS (Irish Health Repository)

    O'Connell, K.

    2014-09-01

    This was an prospective audit composed of medical chart review and patient questionnaire. Relapses were stratified into 3 groups: low, moderate and high intensity. Age, gender, MS subtype, disease duration, expanded disability status scale (EDSS) score, disease modifying therapy (DMT) use and employment status were recorded. Direct costs included GP visits, investigations, clinic visit, consultations with medical staff, medication and admission costs. Indirect costs assessed loss of earnings, partner\\'s loss of earnings, childcare, meals and travel costs.

  2. Development and Validation of an LC-MS/MS Method and Comparison with a GC-MS Method to Measure Phenytoin in Human Brain Dialysate, Blood, and Saliva

    Directory of Open Access Journals (Sweden)

    Raphael Hösli

    2018-01-01

    Full Text Available Phenytoin (PHT is one of the most often used critical dose drugs, where insufficient or excessive dosing can have severe consequences such as seizures or toxicity. Thus, the monitoring and precise measuring of PHT concentrations in patients is crucial. This study develops and validates an LC-MS/MS method for the measurement of phenytoin concentrations in different body compartments (i.e., human brain dialysate, blood, and saliva and compares it with a formerly developed GC-MS method that measures PHT in the same biological matrices. The two methods are evaluated and compared based on their analytical performance, appropriateness to analyze human biological samples, including corresponding extraction and cleanup procedures, and their validation according to ISO 17025/FDA Guidance for Industry. The LC-MS/MS method showed a higher performance compared with the GC-MS method. The LC-MS/MS was more sensitive, needed a smaller sample volume (25 µL and less chemicals, was less time consuming (cleaning up, sample preparation, and analysis, and resulted in a better LOD ( 0.995 for all tested matrices (blood, saliva, and dialysate. For larger sample numbers as in pharmacokinetic/pharmacodynamic studies and for bedside as well as routine analyses, the LC-MS/MS method offers significant advantages over the GC-MS method.

  3. Survey of diagnostic and treatment practices for multiple sclerosis (MS) in Europe. Part 2: Progressive MS, paediatric MS, pregnancy and general management.

    Science.gov (United States)

    Fernández, O; Delvecchio, M; Edan, G; Fredrikson, S; Giovannoni, G; Hartung, H-P; Havrdova, E; Kappos, L; Pozzilli, C; Soerensen, P S; Tackenberg, B; Vermersch, P; Comi, G

    2018-05-01

    The European Charcot Foundation supported the development of a set of surveys to understand current practice patterns for the diagnosis and management of multiple sclerosis (MS) in Europe. Part 2 of the report summarizes survey results related to secondary progressive MS (SPMS), primary progressive MS (PPMS), pregnancy, paediatric MS and overall patient management. A steering committee of MS neurologists developed case- and practice-based questions for two sequential surveys distributed to MS neurologists throughout Europe. Respondents generally favoured changing rather than stopping disease-modifying treatment (DMT) in patients transitioning from relapsing-remitting MS to SPMS, particularly with active disease. Respondents would not initiate DMT in patients with typical PPMS symptoms, although the presence of ≥1 spinal cord or brain gadolinium-enhancing lesion might affect that decision. For patients considering pregnancy, respondents were equally divided on whether to stop treatment before or after conception. Respondents strongly favoured starting DMT in paediatric MS with active disease; recommended treatments included interferon, glatiramer acetate and, in John Cunningham virus negative patients, natalizumab. Additional results regarding practice-based questions and management are summarized. Results of part 2 of the survey of diagnostic and treatment practices for MS in Europe largely mirror results for part 1, with neurologists in general agreement about the treatment and management of SPMS, PPMS, pregnancy and paediatric MS as well as the general management of MS. However, there are also many areas of disagreement, indicating the need for evidence-based recommendations and/or guidelines. © 2018 EAN.

  4. NMR and MS methods for metabonomics.

    Science.gov (United States)

    Dieterle, Frank; Riefke, Björn; Schlotterbeck, Götz; Ross, Alfred; Senn, Hans; Amberg, Alexander

    2011-01-01

    Metabonomics, also often referred to as "metabolomics" or "metabolic profiling," is the systematic profiling of metabolites in bio-fluids or tissues of organisms and their temporal changes. In the last decade, metabonomics has become increasingly popular in drug development, molecular medicine, and other biotechnology fields, since it profiles directly the phenotype and changes thereof in contrast to other "-omics" technologies. The increasing popularity of metabonomics has been possible only due to the enormous development in the technology and bioinformatics fields. In particular, the analytical technologies supporting metabonomics, i.e., NMR, LC-MS, UPLC-MS, and GC-MS have evolved into sensitive and highly reproducible platforms allowing the determination of hundreds of metabolites in parallel. This chapter describes the best practices of metabonomics as seen today. All important steps of metabolic profiling in drug development and molecular medicine are described in great detail, starting from sample preparation, to determining the measurement details of all analytical platforms, and finally, to discussing the corresponding specific steps of data analysis.

  5. CCSVI and MS: no meaning, no fact.

    Science.gov (United States)

    Baracchini, Claudio; Atzori, Matteo; Gallo, Paolo

    2013-03-01

    A condition called "chronic cerebrospinal venous insufficiency" (CCSVI) has been postulated to play a role in the pathogenesis of multiple sclerosis (MS). This hypothesis implies that a complex pattern of extracranial venous stenosis determines a venous reflux into the brain of MS patients, followed by increased intravenous pressure, blood-brain barrier breakdown and iron deposition into the brain parenchyma, thus triggering a local inflammatory response. In this review, we critically analyze the scientific basis of CCSVI, the current literature on the relationship between CCSVI and MS, as well as the ultrasound methodology that has been claimed to provide evidence of impaired cerebral venous drainage. We show that no piece of the CCSVI theory has a solid supportive scientific evidence. The CCSVI appears to be a rather alien condition and its existence should be definitely questioned. Finally, no proven (i.e., based on strict scientific methodology and on the rules of evidence-based medicine) therapeutic effect of the "liberation" procedure (unblocking the extracranial venous obstruction using angioplasty) has been shown up to date.

  6. siMS Score: Simple Method for Quantifying Metabolic Syndrome.

    Science.gov (United States)

    Soldatovic, Ivan; Vukovic, Rade; Culafic, Djordje; Gajic, Milan; Dimitrijevic-Sreckovic, Vesna

    2016-01-01

    To evaluate siMS score and siMS risk score, novel continuous metabolic syndrome scores as methods for quantification of metabolic status and risk. Developed siMS score was calculated using formula: siMS score = 2*Waist/Height + Gly/5.6 + Tg/1.7 + TAsystolic/130-HDL/1.02 or 1.28 (for male or female subjects, respectively). siMS risk score was calculated using formula: siMS risk score = siMS score * age/45 or 50 (for male or female subjects, respectively) * family history of cardio/cerebro-vascular events (event = 1.2, no event = 1). A sample of 528 obese and non-obese participants was used to validate siMS score and siMS risk score. Scores calculated as sum of z-scores (each component of metabolic syndrome regressed with age and gender) and sum of scores derived from principal component analysis (PCA) were used for evaluation of siMS score. Variants were made by replacing glucose with HOMA in calculations. Framingham score was used for evaluation of siMS risk score. Correlation between siMS score with sum of z-scores and weighted sum of factors of PCA was high (r = 0.866 and r = 0.822, respectively). Correlation between siMS risk score and log transformed Framingham score was medium to high for age groups 18+,30+ and 35+ (0.835, 0.707 and 0.667, respectively). siMS score and siMS risk score showed high correlation with more complex scores. Demonstrated accuracy together with superior simplicity and the ability to evaluate and follow-up individual patients makes siMS and siMS risk scores very convenient for use in clinical practice and research as well.

  7. An On-Target Desalting and Concentration Sample Preparation Protocol for MALDI-MS and MS/MS Analysis

    DEFF Research Database (Denmark)

    Zhang, Xumin; Wang, Quanhui; Lou, Xiaomin

    2012-01-01

    2DE coupled with MALDI-MS is one of the most widely used and powerful analytic technologies in proteomics study. The MALDI sample preparation method has been developed and optimized towards the combination of simplicity, sample-cleaning, and sample concentration since its introduction. Here we...... present a protocol of the so-called Sample loading, Matrix loading, and on-target Wash (SMW) method which fulfills the three criteria by taking advantage of the AnchorChip™ targets. Our method is extremely simple and no pre-desalting or concentration is needed when dealing with samples prepared from 2DE...

  8. When a Parent Has MS: A Teenager's Guide

    Science.gov (United States)

    ... can prevent fights. National MS Society | 14 With Strangers When strangers stare or make rude comments about your parent, ... Society helps people affected by MS by funding cutting-edge research, driving change through advocacy, facilitating professional ...

  9. Gas Chromatography (GC) – Mass Spectrometry (MS) analysis of ...

    African Journals Online (AJOL)

    MS. Glycosides, phenolics and alkaloids were indicated in large amount; eugenols and terpenes were also present while saponin, tannins and steroid were absent. Major components detected by GC-MS were 2-Hydroxy hexadecanoic acid ...

  10. Lung Cancer Serum Biomarker Discovery Using Label Free LC-MS/MS

    Science.gov (United States)

    Zeng, Xuemei; Hood, Brian L.; Zhao, Ting; Conrads, Thomas P.; Sun, Mai; Gopalakrishnan, Vanathi; Grover, Himanshu; Day, Roger S.; Weissfeld, Joel L.; Wilson, David O.; Siegfried, Jill M.; Bigbee, William L.

    2011-01-01

    Introduction Lung cancer remains the leading cause of cancer-related death with poor survival due to the late stage at which lung cancer is typically diagnosed. Given the clinical burden from lung cancer, and the relatively favorable survival associated with early stage lung cancer, biomarkers for early detection of lung cancer are of important potential clinical benefit. Methods We performed a global lung cancer serum biomarker discovery study using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in a set of pooled non-small cell lung cancer (NSCLC) case sera and matched controls. Immunoaffinity subtraction was used to deplete the top most abundant serum proteins; the remaining serum proteins were subjected to trypsin digestion and analyzed in triplicate by LC-MS/MS. The tandem mass spectrum data were searched against the human proteome database and the resultant spectral counting data were used to estimate the relative abundance of proteins across the case/control serum pools. The spectral counting derived abundances of some candidate biomarker proteins were confirmed with multiple reaction monitoring MS assays. Results A list of 49 differentially abundant candidate proteins was compiled by applying a negative binomial regression model to the spectral counting data (pbiomarkers with statistically significant differential abundance across the lung cancer case/control pools which, when validated, could improve lung cancer early detection. PMID:21304412

  11. Ellagitannin composition of blackberry as determined by HPLC-ESI-MS and MALDI-TOF-MS.

    Science.gov (United States)

    Hager, Tiffany J; Howard, Luke R; Liyanage, Rohana; Lay, Jackson O; Prior, Ronald L

    2008-02-13

    Blackberries ( Rubus sp.) were evaluated by high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF-MS) to identify the ellagitannins present in flesh, torus (receptacle tissue), and seeds. Most ellagitannins were present (or detectable) only in seed tissues. Ellagitannins identified by HPLC-ESI-MS in the seeds included pedunculagin, casuarictin/potentillin, castalagin/vescalagin, lambertianin A/sanguiin H-6, lambertianin C, and lambertianin D. For several of the ellagitannins, isomeric separation was also obtained. The MALDI-TOF-MS analysis was primarily utilized to evaluate and identify high molecular mass (>1000 Da) ellagitannins. The MALDI analysis verified the presence of the ellagitannins identified by HPLC-ESI-MS including lambertianin A/sanguiin H-6, lambertianin C, and lambertianin D, but the analysis also indicated the presence of several other compounds that were most likely ellagitannins based on the patterns observed in the masses (i.e., loss or addition of a gallic acid moiety to a known ellagitannin). This study determined the presence of several possible isomeric forms of ellagitannins previously unidentified in fruit and presents a possible analytical HPLC method for the analysis of the major ellagitannins present in the fruit.

  12. Determination of 48 fragrance allergens in toys using GC with ion trap MS/MS.

    Science.gov (United States)

    Lv, Qing; Zhang, Qing; Li, Wentao; Li, Haiyu; Li, Pi; Ma, Qiang; Meng, Xianshuang; Qi, Meiling; Bai, Hua

    2013-11-01

    This paper presents a method for the simultaneous determination of 48 fragrance allergens in four types of toys (plastic toys, play clays, plush toys, and paper toys) based on GC with ion trap MS/MS. Compared with single-stage MS, MS/MS is superior in terms of the qualification and quantification of a large range of compounds in complicated matrices. Procedures for extraction and purification were optimized for each toy type. The method proved to be linear over a wide range of concentrations for all analytes with correlation coefficients between 0.9768 and 0.9999. Validation parameters, namely, LODs and LOQs, ranged from 0.005-5.0 and from 0.02-20 mg/kg, respectively. Average recoveries of target compounds (spiked at three concentration levels) were in the range of 79.5-109.1%. Intraday and interday repeatabilities of the proposed method varied from 0.7-10.5% and from 3.1-13.4%, respectively. The proposed method was used to monitor fragrance allergens in commercial toy products. Our findings indicate that this method is an accurate and effective technique for analyzing fragrance allergens in materials composed of complex components. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Development and validation of analytical method for Naftopidil in human plasma by LC–MS/MS

    Directory of Open Access Journals (Sweden)

    Pritam S. Jain

    2015-09-01

    Full Text Available A highly sensitive and simple high-performance liquid chromatographic–tandem mass spectrometric (LC–MS-MS assay is developed and validated for the quantification of Naftopidil in human plasma. Naftopidil is extracted from human plasma by methyl tertiary butyl ether and analyzed using a reversed-phase gradient elution on a discovery C 18 5 μ (50 × 4.6 column. A methanol: 2 mM ammonium formate (90:10 as mobile phase, is used and detection was performed by MS using electrospray ionization in positive mode. Propranolol is used as the internal standard. The lower limits of quantification are 0.495 ng/mL. The calibration curves are linear over the concentration range of 0.495–200.577 ng/mL of plasma for each analyte. This novel LC–MS-MS method shows satisfactory accuracy and precision and is sufficiently sensitive for the performance of pharmacokinetic studies in humans.

  14. SWATH Mass Spectrometry Performance Using Extended Peptide MS/MS Assay Libraries*

    Science.gov (United States)

    Wu, Jemma X.; Song, Xiaomin; Pascovici, Dana; Zaw, Thiri; Care, Natasha; Krisp, Christoph; Molloy, Mark P.

    2016-01-01

    The use of data-independent acquisition methods such as SWATH for mass spectrometry based proteomics is usually performed with peptide MS/MS assay libraries which enable identification and quantitation of peptide peak areas. Reference assay libraries can be generated locally through information dependent acquisition, or obtained from community data repositories for commonly studied organisms. However, there have been no studies performed to systematically evaluate how locally generated or repository-based assay libraries affect SWATH performance for proteomic studies. To undertake this analysis, we developed a software workflow, SwathXtend, which generates extended peptide assay libraries by integration with a local seed library and delivers statistical analysis of SWATH-quantitative comparisons. We designed test samples using peptides from a yeast extract spiked into peptides from human K562 cell lysates at three different ratios to simulate protein abundance change comparisons. SWATH-MS performance was assessed using local and external assay libraries of varying complexities and proteome compositions. These experiments demonstrated that local seed libraries integrated with external assay libraries achieve better performance than local assay libraries alone, in terms of the number of identified peptides and proteins and the specificity to detect differentially abundant proteins. Our findings show that the performance of extended assay libraries is influenced by the MS/MS feature similarity of the seed and external libraries, while statistical analysis using multiple testing corrections increases the statistical rigor needed when searching against large extended assay libraries. PMID:27161445

  15. Comparison of Proteins in Whole Blood and Dried Blood Spot Samples by LC/MS/MS

    Science.gov (United States)

    Chambers, Andrew G.; Percy, Andrew J.; Hardie, Darryl B.; Borchers, Christoph H.

    2013-09-01

    Dried blood spot (DBS) sampling methods are desirable for population-wide biomarker screening programs because of their ease of collection, transportation, and storage. Immunoassays are traditionally used to quantify endogenous proteins in these samples but require a separate assay for each protein. Recently, targeted mass spectrometry (MS) has been proposed for generating highly-multiplexed assays for biomarker proteins in DBS samples. In this work, we report the first comparison of proteins in whole blood and DBS samples using an untargeted MS approach. The average number of proteins identified in undepleted whole blood and DBS samples by liquid chromatography (LC)/MS/MS was 223 and 253, respectively. Protein identification repeatability was between 77 %-92 % within replicates and the majority of these repeated proteins (70 %) were observed in both sample formats. Proteins exclusively identified in the liquid or dried fluid spot format were unbiased based on their molecular weight, isoelectric point, aliphatic index, and grand average hydrophobicity. In addition, we extended this comparison to include proteins in matching plasma and serum samples with their dried fluid spot equivalents, dried plasma spot (DPS), and dried serum spot (DSS). This work begins to define the accessibility of endogenous proteins in dried fluid spot samples for analysis by MS and is useful in evaluating the scope of this new approach.

  16. 50 CFR 660.150 - Mothership (MS) Coop Program.

    Science.gov (United States)

    2010-10-01

    ... follows: (i) Species with formal allocations to the MS Coop Program are Pacific whiting, canary rockfish... issuance for MS permit—(i) Eligibility criteria for MS permit. Only the current owner of a vessel that... mail the application by certified mail to the current address of record in the NMFS permit database...

  17. Simultaneous quantification of the organophosphorus pesticides dimethoate and omethoate in porcine plasma and urine by LC-ESI-MS/MS and flow-injection-ESI-MS/MS.

    Science.gov (United States)

    John, Harald; Eddleston, Michael; Clutton, R Eddie; Worek, Franz; Thiermann, Horst

    2010-05-15

    Dimethoate is an organophosphorus toxicant used in agri- and horticulture as a systemic broad-spectrum insecticide. It also exhibits toxic activity towards mammalian organism provoked by catalytic desulfuration in the liver producing its oxon-derivative omethoate thus inhibiting acetylcholinesterase, initiating cholinergic crisis and ultimately leading to death by respiratory paralysis and cardiovascular collapse. Pharmaco- and toxicokinetic studies in animal models help to broaden basic understanding of medical intervention by antidotes and supportive care. Therefore, we developed and validated a LC-ESI-MS/MS method suitable for the simultaneous, selective, precise (RSD(intra-day) 1-8%; RSD(inter-day) 5-14%), accurate (intra-day: 95-107%; inter-day: 90-115%), and robust quantification of both pesticides from porcine urine and plasma after deproteinization by precipitation and extensive dilution (1:11,250 for plasma and 1:40,000 for urine). Accordingly, lower limits of quantification (0.24-0.49 microg/ml plasma and 0.78-1.56 microg/ml urine) and lower limits of detection (0.12-0.24 microg/ml plasma and 0.39-0.78 microg/ml urine) were equivalent to quite low absolute on-column amounts (1.1-2.1 pg for plasma and 2.0-3.9 pg for urine). The calibration range (0.24-250 microg/ml plasma and 0.78-200 microg/ml urine) was subdivided into two linear ranges (r(2)>or=0.998) each covering nearly two orders of magnitude. The lack of any interfering peak in 6 individual blank specimens from plasma and urine demonstrated the high selectivity of the method. Furthermore, extensive sample dilution causing lowest concentration of potentially interfering matrix ingredients prompted us to develop and validate an additional flow-injection method (FI-ESI-MS/MS). Validation characteristics were as good as for the chromatographic method but sample throughput was enhanced by a factor of 6. Effects on ionization provoked by plasma and urine matrix from 6 individuals as well as in the

  18. Simultaneous quantitative analysis of nine vitamin D compounds in human blood using LC-MS/MS.

    Science.gov (United States)

    Abu Kassim, Nur Sofiah; Gomes, Fabio P; Shaw, Paul Nicholas; Hewavitharana, Amitha K

    2016-01-01

    It has been suggested that each member of the family of vitamin D compounds may have different function(s). Therefore, selective quantification of each compound is important in clinical research. Development and validation attempts of a simultaneous determination method of 12 vitamin D compounds in human blood using precolumn derivatization followed by LC-MS/MS is described. Internal standard calibration with 12 stable isotope labeled analogs was used to correct for matrix effects in MS detector. Nine vitamin D compounds were quantifiable in blood samples with detection limits within femtomole levels. Serum (compared with plasma) was found to be a more suitable sample type, and protein precipitation (compared with saponification) a more effective extraction method for vitamin D assay.

  19. Comparison of LC-ESI-MS and GC-MS for the Analysis of a Synthetic Tabun Sample

    National Research Council Canada - National Science Library

    D'Agostino, Paul

    2003-01-01

    Packed capillary LC-ESI-MS and capillary column GC-MS were compared for the analysis of a synthetic tabun sample as each method has advantages for the analysis of samples containing chemical warfare...

  20. Application of LC–MS/MS for quantitative analysis of glucocorticoids and stimulants in biological fluids

    Directory of Open Access Journals (Sweden)

    Jamshed Haneef

    2013-10-01

    Full Text Available Liquid chromatography tandem mass chromatography (LC–MS/MS is an important hyphenated technique for quantitative analysis of drugs in biological fluids. Because of high sensitivity and selectivity, LC–MS/MS has been used for pharmacokinetic studies, metabolites identification in the plasma and urine. This manuscript gives comprehensive analytical review, focusing on chromatographic separation approaches (column packing materials, column length and mobile phase as well as different acquisition modes (SIM, MRM for quantitative analysis of glucocorticoids and stimulants. This review is not meant to be exhaustive but rather to provide a general overview for detection and confirmation of target drugs using LC–MS/MS and thus useful in the doping analysis, toxicological studies as well as in pharmaceutical analysis. Keywords: LC–MS/MS, Ionization techniques, Glucocorticoids, Stimulants, Hyphenated techniques, Biological fluid

  1. Analysis of benzodiazepines and their metabolites using DBS cards and LC-MS/MS.

    Science.gov (United States)

    Lee, Heesang; Park, Yujin; Jo, Jiyeong; In, Sangwhan; Park, Yonghoon; Kim, Eunmi; Pyo, Jaesung; Choe, Sanggil

    2015-10-01

    Dried Blood Spot (DBS) has been used a blood extraction method for inherited metabolic disorder screening since 1960s. With introduction of LC-MS/MS, not only DBS could be used to analysis drugs in small blood volume, but in various fields, such as toxicology, drug therapeutic monitoring, drug diagnostic screening, and illicit drugs. In toxicology field, many drugs (e.g. benzodiazepines, acetaminophen, small molecule drugs) have been tested with DBS. Compared with earlier blood extraction methods (SPE and LLE), DBS has lots of advantages; lower blood volume (less than 50μL), shorter analysis time caused by a more concise analysis procedure and lower cost. We optimized the DBS procedure and LC-MS/MS conditions for 18 benzodiazepines, seven benzodiazepine metabolites, and one z-drug (zolpidem) analysis in blood. 30μL of whole blood was spotted on FTA DMPK card C and dried for 2h in a desiccator. A 6-mm disk was punched and vortexed for 1min in a centrifuge tube with 300μL methanol/acetonitrile mixture (1:1, v/v). After evaporation, redissolved in 100μL mobile phase of LC-MS/MS and 5μL was injected. In the analysis for 26 target compounds in blood, all of the method validation parameters - LLOD, LLOQ, accuracy (intra- and inter-assay), and precision (intra- and inter-assay) - were satisfied with method validation criteria, within 15%. The results of matrix effect, recovery, and process efficiency were good. We developed a fast and reliable sample preparation method using DBS for 26 benzodiazepines, benzodiazepine metabolites, and z-drug (zolpidem). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Screening of veterinary drug residues in food by LC-MS/MS. Background and challenges.

    Science.gov (United States)

    Delatour, Thierry; Racault, Lucie; Bessaire, Thomas; Desmarchelier, Aurélien

    2018-04-01

    Regulatory agencies and government authorities have established maximum residue limits (MRL) in various food matrices of animal origin for supporting governments and food operators in the monitoring of veterinary drug residues in the food chain, and ultimately in the consumer's plate. Today, about 200 veterinary drug residues from several families, mainly with antibiotic, antiparasitic or antiinflammatory activities, are regulated in a variety of food matrices such as milk, meat or egg. This article provides a review of the regulatory framework in milk and muscle including data from Codex Alimentarius, Europe, the U.S.A., Canada and China for about 220 veterinary drugs. The article also provides a comprehensive overview of the challenge for food control, and emphasizes the pivotal role of liquid chromatography-mass spectrometry (LC-MS), either in tandem with quadrupoles (LC-MS/MS) or high resolution MS (LC-HRMS), for ensuring an adequate consumer protection combined with an affordable cost. The capability of a streamlined LC-MS/MS platform for screening 152 veterinary drug residues in a broad range of raw materials and finished products is highlighted in a production line perspective. The rationale for a suite of four methods intended to achieve appropriate performance in terms of scope and sensitivity is presented. Overall, the platform encompasses one stream for the determination of 105 compounds in a run (based on acidic QuEChERS-like), plus two streams for 23 β-lactams (alkaline QuEChERS-like) and 10 tetracyclines (low-temperature partitioning), respectively, and a dedicated stream for 14 aminoglycosides (molecularly-imprinted polymer).

  3. UFLC-ESI-MS/MS analysis of multiple mycotoxins in medicinal and edible Areca catechu.

    Science.gov (United States)

    Liu, Hongmei; Luo, Jiaoyang; Kong, Weijun; Liu, Qiutao; Hu, Yichen; Yang, Meihua

    2016-05-01

    A robust, sensitive and reliable ultra fast liquid chromatography combined with electrospray ionization tandem mass spectrometry (UFLC-ESI-MS/MS) was optimized and validated for simultaneous identification and quantification of eleven mycotoxins in medicinal and edible Areca catechu, based on one-step extraction without any further clean-up. Separation and quantification were performed in both positive and negative modes under multiple reaction monitoring (MRM) in a single run with zearalanone (ZAN) as internal standard. The chromatographic conditions and MS/MS parameters were carefully optimized. Matrix-matched calibration was recommended to reduce matrix effects and improve accuracy, showing good linearity within wide concentration ranges. Limits of quantification (LOQ) were lower than 50 μg kg(-1), while limits of detection (LOD) were in the range of 0.1-20 μg kg(-1). The accuracy of the developed method was validated for recoveries, ranging from 85% to 115% with relative standard deviation (RSD) ≤14.87% at low level, from 75% to 119% with RSD ≤ 14.43% at medium level and from 61% to 120% with RSD ≤ 13.18% at high level, respectively. Finally, the developed multi-mycotoxin method was applied for screening of these mycotoxins in 24 commercial samples. Only aflatoxin B2 and zearalenone were found in 2 samples. This is the first report on the application of UFLC-ESI(+/-)-MS/MS for multi-class mycotoxins in A. catechu. The developed method with many advantages of simple pretreatment, rapid determination and high sensitivity is a proposed candidate for large-scale detection and quantification of multiple mycotoxins in other complex matrixes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. 75 FR 14606 - Medicare Program; Request for Nominations to the Advisory Panel on Ambulatory Payment...

    Science.gov (United States)

    2010-03-26

    ..., CPHQ Patrick A. Grusenmeyer, Sc.D., FACHE David Halsey, M.D. Judith T. Kelly, B.S.H.A., RHIT, RHIA, CCS....D.* Daniel Pothen, M.S., RHIA, CPHIMS, CCS, CCS-P, CHC Gregory J. Przbylski, M.D. Russ Ranallo, M.S...

  5. UPLC-MS/MS determination of ptaquiloside and pterosin B in preserved natural water

    DEFF Research Database (Denmark)

    Clauson-Kaas, Frederik; Hansen, Hans Chr. Bruun; Strobel, Bjarne W.

    2016-01-01

    and preconcentration of samples with solid phase extraction, before analyte quantification with UPLC-MS/MS. By including gradient elution and optimizing the liquid chromatography mobile phase buffer system, a total run cycle of 5 min was achieved, with method detection limits, including preconcentration, of 8 and 4 ng....../L for ptaquiloside and pterosin B, respectively. The use of loganin as internal standard improved repeatability of the determination of both analytes, though it could not be employed for sample preparation. Buffering raw water samples in situ with ammonium acetate to pH ∼5.5 decisively increased sample integrity...

  6. Shotgun proteomics of plant plasma membrane and microdomain proteins using nano-LC-MS/MS.

    Science.gov (United States)

    Takahashi, Daisuke; Li, Bin; Nakayama, Takato; Kawamura, Yukio; Uemura, Matsuo

    2014-01-01

    Shotgun proteomics allows the comprehensive analysis of proteins extracted from plant cells, subcellular organelles, and membranes. Previously, two-dimensional gel electrophoresis-based proteomics was used for mass spectrometric analysis of plasma membrane proteins. In order to get comprehensive proteome profiles of the plasma membrane including highly hydrophobic proteins with a number of transmembrane domains, a mass spectrometry-based shotgun proteomics method using nano-LC-MS/MS for proteins from the plasma membrane proteins and plasma membrane microdomain fraction is described. The results obtained are easily applicable to label-free protein semiquantification.

  7. ms_lims, a simple yet powerful open source laboratory information management system for MS-driven proteomics.

    Science.gov (United States)

    Helsens, Kenny; Colaert, Niklaas; Barsnes, Harald; Muth, Thilo; Flikka, Kristian; Staes, An; Timmerman, Evy; Wortelkamp, Steffi; Sickmann, Albert; Vandekerckhove, Joël; Gevaert, Kris; Martens, Lennart

    2010-03-01

    MS-based proteomics produces large amounts of mass spectra that require processing, identification and possibly quantification before interpretation can be undertaken. High-throughput studies require automation of these various steps, and management of the data in association with the results obtained. We here present ms_lims (http://genesis.UGent.be/ms_lims), a freely available, open-source system based on a central database to automate data management and processing in MS-driven proteomics analyses.

  8. Analysis of pesticide residues in strawberries and soils by GC-MS/MS, LC-MS/MS and two-dimensional GC-time-of-flight MS comparing organic and integrated pest management farming.

    Science.gov (United States)

    Fernandes, Virgínia C; Lehotay, Steven J; Geis-Asteggiante, Lucía; Kwon, Hyeyoung; Mol, Hans G J; van der Kamp, Henk; Mateus, Nuno; Domingues, Valentina F; Delerue-Matos, Cristina

    2014-01-01

    This study analysed 22 strawberry and soil samples after their collection over the course of 2 years to compare the residue profiles from organic farming with integrated pest management practices in Portugal. For sample preparation, we used the citrate-buffered version of the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. We applied three different methods for analysis: (1) 27 pesticides were targeted using LC-MS/MS; (2) 143 were targeted using low pressure GC-tandem mass spectrometry (LP-GC-MS/MS); and (3) more than 600 pesticides were screened in a targeted and untargeted approach using comprehensive, two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOF-MS). Comparison was made of the analyses using the different methods for the shared samples. The results were similar, thereby providing satisfactory confirmation of both similarly positive and negative findings. No pesticides were found in the organic-farmed samples. In samples from integrated pest management practices, nine pesticides were determined and confirmed to be present, ranging from 2 µg kg(-1) for fluazifop-p-butyl to 50 µg kg(-1) for fenpropathrin. Concentrations of residues in strawberries were less than European maximum residue limits.

  9. NMR and MS Methods for Metabolomics.

    Science.gov (United States)

    Amberg, Alexander; Riefke, Björn; Schlotterbeck, Götz; Ross, Alfred; Senn, Hans; Dieterle, Frank; Keck, Matthias

    2017-01-01

    Metabolomics, also often referred as "metabolic profiling," is the systematic profiling of metabolites in biofluids or tissues of organisms and their temporal changes. In the last decade, metabolomics has become more and more popular in drug development, molecular medicine, and other biotechnology fields, since it profiles directly the phenotype and changes thereof in contrast to other "-omics" technologies. The increasing popularity of metabolomics has been possible only due to the enormous development in the technology and bioinformatics fields. In particular, the analytical technologies supporting metabolomics, i.e., NMR, UPLC-MS, and GC-MS, have evolved into sensitive and highly reproducible platforms allowing the determination of hundreds of metabolites in parallel. This chapter describes the best practices of metabolomics as seen today. All important steps of metabolic profiling in drug development and molecular medicine are described in great detail, starting from sample preparation to determining the measurement details of all analytical platforms, and finally to discussing the corresponding specific steps of data analysis.

  10. Quantification of phytoprostanes - bioactive oxylipins - and phenolic compounds of Passiflora edulis Sims shell using UHPLC-QqQ-MS/MS and LC-IT-DAD-MS/MS.

    Science.gov (United States)

    Medina, Sonia; Collado-González, Jacinta; Ferreres, Federico; Londoño-Londoño, Julián; Jiménez-Cartagena, Claudio; Guy, Alexandre; Durand, Thierry; Galano, Jean-Marie; Gil-Izquierdo, Angel

    2017-08-15

    The genus Passiflora, comprising about 500 species, is the largest in the Passion flower family. Passiflora edulis Sims f. edulis (gulupa) is one of the most important fruits cultivated in Colombia. In recent years and due to its organoleptic and bioactive properties, its exports have significantly increased. In this work, six new bioactive oxylipins -phytoprostanes - were detected in gulupa shell by a UHPLC-QqQ-MS/MS method: F 1t -phytoprostanes and D 1t -phytoprostanes were the predominant and minor classes, respectively. Moreover, the polyphenol profile of the shell was investigated and we were able to detect and quantify phenolic compounds that have not been described previously, like luteolin-8-C-(2-O-rhamnosyl)hexoside and quercetin-3-O-(6″-acetyl)glucosyl-2″-sinapic acid. Consequently, this study provides new insights into the importance of gulupa shell as a valuable option in the design of new beverages rich in antioxidant phytochemicals, as part of a well-balanced diet, and in the process and quality control of such products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. VOC identification and inter-comparison from laboratory biomass burning using PTR-MS and PIT-MS

    Science.gov (United States)

    C. Warneke; J. M. Roberts; P. Veres; J. Gilman; W. C. Kuster; I. Burling; R. Yokelson; J. A. de Gouw

    2011-01-01

    Volatile organic compounds (VOCs) emitted from fires of biomass commonly found in the southeast and southwest U.S. were investigated with PTR-MS and PIT-MS, which are capable of fast measurements of a large number of VOCs. Both instruments were calibrated with gas standards and mass dependent calibration curves are determined. The sensitivity of the PIT-MS linearly...

  12. Analytical Method Details (MS): SE60_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available stem and Waters Q-Tof Premier UPLC-QTOF-MS ESI Positive The supernatant (3 μl) were subsequently subjected to metabolome...g were conducted according to a previously described method (Matsuda et al., 2009, 2010). Briefly, metabolome

  13. Analytical Method Details (MS): SE53_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available .25-μl film Rtx-5 Sil MS stationary phase (RESTEK, Bellefonte, USA) for metabolome... analysis. Helium was used as the carrier gas at a constant flow rate of 1 ml min-1. The temperature program for metabolome

  14. Identification of hormone esters in injection site in muscle tissues by LC/MS/MS.

    Science.gov (United States)

    Costain, R M; Fesser, A C E; McKenzie, D; Mizuno, M; MacNeil, J D

    2008-12-01

    The detection of hormone abuse for growth promotion in food animal production is a global concern. Initial testing for hormones in Canada was directed at the compounds approved for use in beef cattle, melengestrol acetate, trenbolone acetate and zeranol, and the banned compound diethylstilbestrol (DES). No hormonal growth promoters are approved for use in veal production in Canada. However, instances of use of trenbolone and clenbuterol were detected in Canada in the 1990s. During the development of a new analytical method for testosterone and progesterone, there were reports of suspicious injection sites being found in veal calves. Upon implementation of the method, analysis of investigative samples revealed significant residues of testosterone in some injection sites. To prove that the source of these residues was exogenous, a fully validated method for hormone esters was developed to confirm the presence of exogenous hormones in these injection sites. The QUECHERS model was employed in methods development and resulted in a simple, effective extraction technique that consisted of sample pre-homogenization, liquid/liquid partitioning, extract dilution, filtration and use of LC/MS/MS to provide detection selectivity. The result was an adaptable MS/MS confirmation technique that meets the needs of Canadian regulatory authorities to confirm the misuse of injectable testosterone, and potentially other hormones, in food animal production.

  15. UPLC-MS/MS Method for Simultaneous Determination of Three Major Metabolites of Mequindox in Holothurian

    Directory of Open Access Journals (Sweden)

    Huihui Liu

    2018-01-01

    Full Text Available This study developed an ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS method for the detection of three major metabolites of mequindox, including 3-methyl-quinoxaline-2-carboxylic acid, 1-desoxymequindox, and 1,4-bisdesoxymequindox (MQCA, 1-DMEQ, and BDMEQ, in holothurian. Target analytes were simplified with ultrasound-assisted acidolysis extracted without complicated enzymolysis steps. After that, each sample was centrifuged and purified by an Oasis MAX cartridge. Then, the processed samples were separated and monitored by UPLC-MS/MS. This developed method has been validated according to FDA criteria. At fortified levels of 2, 10, and 20 μg/kg, recoveries ranged from 82.5% to 93.5% with the intraday RSD less than 7.27% and interday RSD less than 11.8%. The limit of detection (LOD of all the three metabolites ranged from 0.21 to 0.48 μg/kg, while the limit of quantification (LOQ ranged from 0.79 to 1.59 μg/kg. On application to commercial samples, 14 of 20 samples were detected positive for the three target analytes, with positive rate at 70 percentage. The result indicated that this method was specific, sensitive, and suitable for the quantification and conformation of the three major metabolites of MEQ in holothurian.

  16. metaMS: An open-source pipeline for GC–MS-based untargeted metabolomics

    NARCIS (Netherlands)

    Wehrens, H.R.M.J.; Weingart, G.; Mattivi, F.

    2014-01-01

    Untargeted metabolomics are rapidly becoming an important tool for studying complex biological samples. Gas chromatography–mass spectrometry (GC–MS) is the most widely used analytical technology for metabolomic analysis of compounds that are volatile or can be chemically derivatised into volatile

  17. Analytical Method Details (MS): SE57_MS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available TQD, UPLC (Waters) UPLC-QTOF-MS ESI N.A. All the solutions of authentic....1% formic acid), with a 2.5 min cycle in the isocratic mode. The ionized authentic compounds were detected ... optimal CV and CE were determined automatically for 497 of these compounds using the software QuanOptimize

  18. Multiclass determination and confirmation of antibiotic residues in honey using LC-MS/MS.

    Science.gov (United States)

    Lopez, Mayda I; Pettis, Jeffery S; Smith, I Barton; Chu, Pak-Sin

    2008-03-12

    A multiclass method has been developed for the determination and confirmation in honey of tetracyclines (chlortetracycline, doxycycline, oxytetracycline, and tetracycline), fluoroquinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, and sarafloxacin), macrolides (tylosin), lincosamides (lincomycin), aminoglycosides (streptomycin), sulfonamides (sulfathiazole), phenicols (chloramphenicol), and fumagillin residues using liquid chromatography tandem mass spectrometry (LC-MS/MS). Erythromycin (a macrolide) and monensin (an ionophore) can be detected and confirmed but not quantitated. Honey samples (approximately 2 g) are dissolved in 10 mL of water and centrifuged. An aliquot of the supernatant is used to determine streptomycin. The remaining supernatant is filtered through a fine-mesh nylon fabric and cleaned up by solid phase extraction. After solvent evaporation and sample reconstitution, 15 antibiotics are assayed by LC-MS/MS using electrospray ionization (ESI) in positive ion mode. Afterward, chloramphenicol is assayed using ESI in negative ion mode. The method has been validated at the low part per billion levels for most of the drugs with accuracies between 65 and 104% and coefficients of variation less than 17%. The evaluation of matrix effects caused by honey of different floral origin is presented.

  19. UP-HILIC-MS/MS to Determine the Action Pattern of Penicillium sp. Dextranase

    Science.gov (United States)

    Yi, Lin; Sun, Xue; Du, Kenze; Ouyang, Yilan; Wu, Chengling; Xu, Naiyu; Linhardt, Robert J.; Zhang, Zhenqing

    2015-07-01

    Investigation of the action pattern of enzymes acting on carbohydrates is challenging, as both the substrate and the digestion products are complex mixtures. Dextran and its enzyme-derived oligosaccharides are widely used for many industrial applications. In this work, a new method relying on ultra-performance hydrophilic interaction liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UP-HILIC- Q/TOF-MS/MS) was developed to analyze a complex mixture of dextran oligosaccharide products to determine the action pattern of dextranase. No derivatization of oligosaccharides was required and the impact of the α- and β-configurations of the native oligosaccharides on the chromatographic separation was eliminated. The 1→6, 1→3, 1→4 backbone linkages and the branch linkages of these oligosaccharides were all distinguished from diagnostic ions in their MS/MS spectra, including fragments corresponding to 0,2A, 0,3A, 0,4A, B-H2O, 2,5A, and 3,5A. The sequences of the oligosaccharide products were similarly established. Thus, the complex oligosaccharide mixtures in dextran digestion products were profiled and identified using this method. The more enzyme-resistant structures in dextran were established using much less sample, labor, time, and uncertainty than in previous studies. This method provides an efficient, sensitive, and straightforward way to monitor the entire process of digestion, establish the action pattern of the dextranase from Penicillium sp., and to support the proper industrial application of dextranase.

  20. Taxus ingredients in the red arils of Taxus baccata L. determined by HPLC-MS/MS.

    Science.gov (United States)

    Siegle, Lydia; Pietsch, Jörg

    2018-02-09

    Taxus baccata L. is an evergreen conifer whose plant parts are cardiotoxic. Only the red arils of the berries are described as non-toxic and taxane-free. Extraction and HPLC-MS/MS methods were developed for the investigation of the Taxus compounds 3,5-dimethoxyphenol, 10-deacetylbaccatin III, baccatin III, cephalomannine, taxol A and taxinine M in the red arils of the yew berries. MethodologyA liquid-liquid extraction method for the red arils of the fruits from three yews were developed. An accurate (ESI+) HPLC-MS/MS method was performed for the simultaneous detection and determination of the target compounds in multiple reaction monitoring (MRM) mode. All Taxus agents obtained were detected in the red arils. Highest concentrations were determined for baccatin III and 10-deacetylbaccatin III. The developed quantitative method is reliable and selective and was successfully applied for quantification of selected Taxus ingredients in red arils of Taxus baccata. It was disproved that the red arils of the berries do not contain the selected Taxus compounds. Copyright © 2018 John Wiley & Sons, Ltd.

  1. Pharmacokinetic studies of bergapten in dog plasma by using a LC-MS/MS method studies.

    Science.gov (United States)

    Gao, Y; Liu, Y Z; Zhang, X-M; Zhou, Y; Zhang, X; Dong, C-Y

    2013-07-01

    A sensitive LC-MS/MS method was developed for the determination of bergapten in dog plasma. The chromatographic separation was carried out on a Hypersil ODS column with a mobile phase consisting of methanol-water. The plasma sample was precipitated with methanol and prepare for injecting onto the LC-MS/MS system. The detection was performed on a triple quadrupole tandem mass spectrometer by MRM via electro spray ionization source. The standard curve for bergapten was linear over the concentration range of 0.5-500 ng/mL with a lower limit of quantification of 0.5 ng/mL. The inter-day and intra-day precision (R.S.D.%) for bergapten varied between 3.4 and 11.5. The corresponding inter-day and intra-day accuracy (Bias%) ranged between -3.8 and 6.9. For the pharmacokinetic analysis of serum, the mean (SD) values obtained for the bergapten were as follows: Cmax, 228.5 (14.3) ng/ml; Tmax, 4.2 (0.4) h; t1/2, 6.9 (2.3) h; AUC0-t h, 2507.2 (168.5) ng · h/mL and AUC0-∞, 3 219.2 (211.4) ng · h/mL, respectively. © Georg Thieme Verlag KG Stuttgart · New York.

  2. ToF-SIMS Parallel Imaging MS/MS of Lipid Species in Thin Tissue Sections.

    Science.gov (United States)

    Bruinen, Anne Lisa; Fisher, Gregory L; Heeren, Ron M A

    2017-01-01

    Unambiguous identification of detected species is essential in complex biomedical samples. To date, there are not many mass spectrometry imaging techniques that can provide both high spatial resolution and identification capabilities. A new and patented imaging tandem mass spectrometer, exploiting the unique characteristics of the nanoTOF II (Physical Electronics, USA) TOF-SIMS TRIFT instrument, was developed to address this.Tandem mass spectrometry is based on the selection of precursor ions from the full secondary ion spectrum (MS 1 ), followed by energetic activation and fragmentation, and collection of the fragment ions to obtain a tandem MS spectrum (MS 2 ). The PHI NanoTOF II mass spectrometer is equipped with a high-energy collision induced dissociation (CID) fragmentation cell as well as a second time-of-flight analyzer developed for simultaneous ToF-SIMS and tandem MS imaging experiments.We describe here the results of a ToF-SIMS imaging experiment on a thin tissue section of an infected zebrafish as a model organism for tuberculosis. The focus is on the obtained ion distribution plot of a fatty acid as well as its identification by tandem mass spectrometry.

  3. Determination of chlormequat in pig serum and sow milk by LC-MS/MS.

    Science.gov (United States)

    Poulsen, M E; Christensen, H B; Sørensen, M T; Leffers, H; Andersen, J H

    2007-11-01

    Chlormequat is a plant growth regulator widely used on cereals, and there is general concern that it may impair human fertility. A LC-MS/MS method for the analysis of chlormequat in milk and serum was developed and validated in connection with an investigation on the effect of chlormequat on pig reproduction. Validation of the method was based on recovery tests at three spiking levels, determined as double determinations and repeated at least four times. Samples were extracted with methanol-water-acetic acid, centrifuged, filtrated and determined by LC-MS/MS. The mean recoveries were in the range 80-110%, and the LOD was 0.2 ng/g for serum and 0.3 ng/g for milk. The values for repeatability and reproducibility were within 2/3 of the limits given by the Horwitz equation. Samples of pig serum (59) and sow milk (27) were analyzed using the method. Chlormequat was determined in four milk samples in the range of 0.4 ng/g to 1.2 ng/g and in all serum samples in the range of 0.2 ng/g-4.0 ng/g.

  4. Potential Health Benefits and Metabolomics of Camel Milk by GC-MS and ICP-MS.

    Science.gov (United States)

    Ahamad, Syed Rizwan; Raish, Mohammad; Ahmad, Ajaz; Shakeel, Faiyaz

    2017-02-01

    None of the research reports reveals the metabolomics and elemental studies on camel milk. Recent studies showed that camel milk possesses anticancer and anti-inflammatory activity. Metabolomics and elemental studies were carried out in camel milk which showed us the pathways and composition that are responsible for the key biological role of camel milk. Camel milk was dissolved in methanol and chloroform fraction and then vortexed and centrifuged. Both the fractions were derivatized by N,O-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) and TMCS after nitrogen purging and analyzed by GC-MS. Camel milk was also analyzed by ICP-MS after microwave digestion. We found that higher alkanes and fatty acids are present in the chloroform fraction and amino acids, sugars and fatty acid derivatives are present in aqueous fractions. All the heavy metals like As, Pb, Cd, Co, Cu, and Ni were in the safe limits in terms of maximum daily intake of these elements. Na, K, Mg, and Ca were also present in the safe limits in terms of maximum daily intake of these elements. These results suggested that the camel milk drinking is safe and there is no health hazard. The present data of GC-MS and ICP-MS correlate the activities related to camel milk.

  5. Long term anoxia in rainbow trout investigated by 2-DE and MS/MS

    DEFF Research Database (Denmark)

    Wulff, Tune; Jessen, Flemming; Roepstorff, P.

    2008-01-01

    Twenty-four hours of N-2 induced anoxia induced global perturbations on protein expression in rainbow trout hypodermal fibroblasts cell line. Anoxia was obtained by depleting the medium of O-2 by flushing with N-2, and protein changes were studied by 2-DE coupled with MS providing quantitative...

  6. Study of the performance of three LC-MS/MS platforms for analysis of perfluorinated compounds

    Energy Technology Data Exchange (ETDEWEB)

    Llorca, Marta; Farre, Marinella [IDAEA-CSIC, Department of Environmental Chemistry, Barcelona (Spain); Pico, Yolanda [Universitat de Valencia, Laboratori de Nutricio i Bromatologia, Facultat de Farmacia, Burjassot, Valencia (Spain); Barcelo, Damia [IDAEA-CSIC, Department of Environmental Chemistry, Barcelona (Spain); King Saud University, Riyadh (Saudi Arabia)

    2010-10-15

    The analytical suitabilities of three different liquid chromatography-tandem mass spectrometry (LC-MS/MS) systems, (1) triple quadrupole (QqQ), (2) conventional 3D ion trap (IT), and (3) quadrupole-linear IT (QqLIT), to determine trace levels of perfluorinated compounds (PFCs) in fish and shellfish were compared. Sample preparation was performed using alkaline extraction and solid-phase-extraction cleanup. This evaluation was focused on both quantitative (sensitivity, precision, and accuracy) and qualitative (identification capabilities) aspects. In the three instruments, the former facet was evaluated using selected reaction monitoring (SRM), which is the standard mode for quantitative LC-MS/MS analysis. Accuracy was similar in the three systems, with recoveries always over 70 %. Precision was better for the QqLIT and QqQ systems (7-15%) than for the IT system (10-17%). The QqLIT (working in SRM mode) and QqQ systems offered a linear dynamic range of at least 3 orders of magnitude, whereas that of the IT system was 2 orders of magnitude. The QqLIT system achieved at least 20-fold higher sensitivity than the QqQ system, and this was at least tenfold higher sensitivity than for the IT system. In the IT system, identification was based on sensitive full mass range acquisition and MS{sup n} fragmentation and in the QqLIT system, it was based on the use of an information-dependent-acquisition scan function, which allows the combination of an SRM or MS full scan acting as the survey scan and an enhanced product ion scan followed by MS{sup 3} as the dependent scan in the same analysis. Three instruments were applied to monitor the content in fish and shellfish (anchovies, swordfish, tuna, mussels, and oysters) obtained from Valencia and Barcelona markets (Spain). The eight target PFCs were detected at mean concentrations in the range from 10 ng kg {sup -1} (perfluoro-7-methyloctanoic acid and perfluoro-1-decanesulfonate) to 4,200 ng kg {sup -1} (perfluoropentanoic acid

  7. Identification and quantification of cardiac glycosides in blood and urine samples by HPLC/MS/MS.

    Science.gov (United States)

    Guan, F; Ishii, A; Seno, H; Watanabe-Suzuki, K; Kumazawa, T; Suzuki, O

    1999-09-15

    Cardiac glycosides (CG) are of forensic importance because of their toxicity and the fact that very limited methods are available for identification of CG in biological samples. In this study, we have developed an identification and quantification method for digoxin, digitoxin, deslanoside, digoxigenin, and digitoxigenin by high-performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS). CG formed abundant [M + NH4]+ ions and much less abundant [M + H]+ ions as observed with electrospray ionization (ESI) source and ammonium formate buffer. Under mild conditions for collision-induced dissociation (CID), each [M + NH4]+ ion fragmented to produce a dominant daughter ion, which was essential to the sensitive method of selected reaction monitoring (SRM) quantification of CG achieved in this study. SRM was compared with selected ion monitoring (SIM) regarding the effects of sample matrixes on the methodology. SRM produced lower detection limits with biological samples than SIM, while both methods produced equal detection limits with CG standards. On the basis of the HPLC/MS/MS results for CG, we have proposed some generalized points for conducting sensitive SRM measurements, in view of the property of analytes as well as instrumental conditions such as the type of HPLC/MS interface and CID parameters. Analytes of which the molecular ion can produce one abundant daughter ion with high yield under CID conditions may be sensitively measured by SRM. ESI is the most soft ionization source developed so far and can afford formation of the fragile molecular ions that are necessary for sensitive SRM detection. Mild CID conditions such as low collision energy and low pressure of collision gas favor production of an abundant daughter ion that is essential to sensitive SRM detection. This knowledge may provide some guidelines for conducting sensitive SRM measurements of very low concentrations of drugs or toxicants in biological samples.

  8. Segmental analysis of amphetamines in hair using a sensitive UHPLC-MS/MS method.

    Science.gov (United States)

    Jakobsson, Gerd; Kronstrand, Robert

    2014-06-01

    A sensitive and robust ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for quantification of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine and 3,4-methylenedioxy methamphetamine in hair samples. Segmented hair (10 mg) was incubated in 2M sodium hydroxide (80°C, 10 min) before liquid-liquid extraction with isooctane followed by centrifugation and evaporation of the organic phase to dryness. The residue was reconstituted in methanol:formate buffer pH 3 (20:80). The total run time was 4 min and after optimization of UHPLC-MS/MS-parameters validation included selectivity, matrix effects, recovery, process efficiency, calibration model and range, lower limit of quantification, precision and bias. The calibration curve ranged from 0.02 to 12.5 ng/mg, and the recovery was between 62 and 83%. During validation the bias was less than ±7% and the imprecision was less than 5% for all analytes. In routine analysis, fortified control samples demonstrated an imprecision <13% and control samples made from authentic hair demonstrated an imprecision <26%. The method was applied to samples from a controlled study of amphetamine intake as well as forensic hair samples previously analyzed with an ultra high performance liquid chromatography time of flight mass spectrometry (UHPLC-TOF-MS) screening method. The proposed method was suitable for quantification of these drugs in forensic cases including violent crimes, autopsy cases, drug testing and re-granting of driving licences. This study also demonstrated that if hair samples are divided into several short segments, the time point for intake of a small dose of amphetamine can be estimated, which might be useful when drug facilitated crimes are investigated. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Efficient analysis and extraction of MS/MS result data from Mascot™ result files

    Directory of Open Access Journals (Sweden)

    Sickmann Albert

    2005-12-01

    Full Text Available Abstract Background Mascot™ is a commonly used protein identification program for MS as well as for tandem MS data. When analyzing huge shotgun proteomics datasets with Mascot™'s native tools, limits of computing resources are easily reached. Up to now no application has been available as open source that is capable of converting the full content of Mascot™ result files from the original MIME format into a database-compatible tabular format, allowing direct import into database management systems and efficient handling of huge datasets analyzed by Mascot™. Results A program called mres2x is presented, which reads Mascot™ result files, analyzes them and extracts either selected or all information in order to store it in a single file or multiple files in formats which are easier to handle downstream of Mascot™. It generates different output formats. The output of mres2x in tab format is especially designed for direct high-performance import into relational database management systems using native tools of these systems. Having the data available in database management systems allows complex queries and extensive analysis. In addition, the original peak lists can be extracted in DTA format suitable for protein identification using the Sequest™ program, and the Mascot™ files can be split, preserving the original data format. During conversion, several consistency checks are performed. mres2x is designed to provide high throughput processing combined with the possibility to be driven by other computer programs. The source code including supplement material and precompiled binaries is available via http://www.protein-ms.de and http://sourceforge.net/projects/protms/. Conclusion The database upload allows regrouping of the MS/MS results using a database management system and complex analyzing queries using SQL without the need to run new Mascot™ searches when changing grouping parameters.

  10. Application of CE-ICP-MS and CE-ESI-MS/MS for identification of Zn-binding ligands in Goji berries extracts.

    Science.gov (United States)

    Ruzik, Lena; Kwiatkowski, Piotr

    2018-06-01

    The identification of groups of ligands binding metals is a crucial issue for the better understanding of their bioaccessibility. In the current study, we have intended an approach for identification of Zn-binding ligands based on using capillary electrophoresis combined with inductively coupled plasma mass spectrometry (CE-ICP-MS) and tandem electrospray ionization mass spectrometry (CE-ESI-MS/MS). The approach, which featured the use of the coupling of capillary electrophoresis with inductively coupled plasma mass spectrometry allows to separate and observe zinc ions present in complexes with respect to their size and charge and to identify nine compounds with zinc isotopic profile. CE-ICP-MS provides us with information about presence of zinc species and elemental information about zinc distribution. CE-ESI-MS/MS provide us with information about the most favorable Zn binding ligands: amino acids, flavonols, stilbenoids, fenolic acids and carotenoids. The presented work is the continuation of previous studies based on using LC-ESI-MS/MS, though, now we presented a new solutions with the possibility of changing detectors without changing the separation techniques, what is important without re-optimizing the method. The new presented method allows to identify the zinc-binding ligands in shorter time. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Tropospheric VOC measurements by PTR-MS

    International Nuclear Information System (INIS)

    Hansel, A.; Wisthaler, A.; Graus, M.; Grabmer, W.

    2002-01-01

    Full text: O 3 is formed photochemically from the photolysis of NO 2 , and because O 3 reacts rapidly with NO these reactions result in a photoequilibrium between NO, NO 2 with no net formation or loss of O 3 , However, in the presence of volatile organic compounds (VOCs), the degradation reactions of VOCs lead to the formation of intermediate peroxy radicals which react with NO, converting NO to NO 2 , which then photolyze to form O 3 . Thus, in order to understand quantitatively tropospheric ozone chemistry, it is necessary to know the VOC distribution within the troposphere as well as VOC fluxes from individual sources. Examples will be presented how the use of Proton Transfer Reaction Mass Spectrometry (PTR-MS) has enhanced our understanding of anthropogenic VOC emissions, biosphere-atmosphere exchange processes, and photochemical processing of both anthropogenic and biogenic VOCs in the troposphere. (author)

  12. Adaptation of GAMANAL to MS-DOS

    International Nuclear Information System (INIS)

    Nagy, S.

    1990-04-01

    The public domain gamma spectrum analysis programme GAMANAL was adapted for use with personal computers running with MS-DOS or equivalent operating system. The original command structure of GAMANAL, and its algorithms were kept unchanged; the facilities to read spectra from different multichannel analyzer formats were added. In the completed PC version, GAMANAL runs in a batch mode, without graphics presentation or menu-oriented interaction with the operator. The operation and performance of the PC version of GAMANAL was compared with some commercial software, in respect to peak sensitivity, multiplet resolution, and accuracy of area determination. The study indicates that the GAMANAL analysis yields results as good or better than other programmes. 4 refs

  13. Soil analyses by ICP-MS (Review)

    International Nuclear Information System (INIS)

    Yamasaki, Shin-ichi

    2000-01-01

    Soil analyses by inductively coupled plasma mass spectrometry (ICP-MS) are reviewed. The first half of the paper is devoted to the development of techniques applicable to soil analyses, where diverse analytical parameters are carefully evaluated. However, the choice of soil samples is somewhat arbitrary, and only a limited number of samples (mostly reference materials) are examined. In the second half, efforts are mostly concentrated on the introduction of reports, where a large number of samples and/or very precious samples have been analyzed. Although the analytical techniques used in these reports are not necessarily novel, valuable information concerning such topics as background levels of elements in soils, chemical forms of elements in soils and behavior of elements in soil ecosystems and the environment can be obtained. The major topics discussed are total elemental analysis, analysis of radionuclides with long half-lives, speciation, leaching techniques, and isotope ratio measurements. (author)

  14. Single-cell analysis by ICP-MS/MS as a fast tool for cellular bioavailability studies of arsenite.

    Science.gov (United States)

    Meyer, S; López-Serrano, A; Mitze, H; Jakubowski, N; Schwerdtle, T

    2018-01-24

    Single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS) has become a powerful and fast tool to evaluate the elemental composition at a single-cell level. In this study, the cellular bioavailability of arsenite (incubation of 25 and 50 μM for 0-48 h) has been successfully assessed by SC-ICP-MS/MS for the first time directly after re-suspending the cells in water. This procedure avoids the normally arising cell membrane permeabilization caused by cell fixation methods (e.g. methanol fixation). The reliability and feasibility of this SC-ICP-MS/MS approach with a limit of detection of 0.35 fg per cell was validated by conventional bulk ICP-MS/MS analysis after cell digestion and parallel measurement of sulfur and phosphorus.

  15. Multisteroid LC–MS/MS assay for glucocorticoids and androgens and its application in Addison's disease

    Science.gov (United States)

    Methlie, Paal; Hustad, Steinar; Kellman, Ralf; Almås, Bjørg; Erichsen, Martina M; Husebye, Eystein S; Løvås, Kristian

    2013-01-01

    Objective Liquid chromatography–tandem mass spectrometry (LC–MS/MS) offers superior analytical specificity compared with immunoassays, but it is not available in many regions and hospitals due to expensive instrumentation and tedious sample preparation. Thus, we developed an automated, high-throughput LC–MS/MS assay for simultaneous quantification of ten endogenous and synthetic steroids targeting diseases of the hypothalamic–pituitary–adrenal axis and gonads. Methods Deuterated internal standards were added to 85 μl serum and processed by liquid–liquid extraction. Cortisol, cortisone, prednisolone, prednisone, 11-deoxycortisol, dexamethasone, testosterone, androstenedione and progesterone were resolved by ultra-high-pressure chromatography on a reversed-phase column in 6.1 min and detected by triple-quadrupole mass spectrometry. The method was used to assess steroid profiles in women with Addison's disease (AD, n=156) and blood donors (BDs, n=102). Results Precisions ranged from 4.5 to 10.1% relative standard deviations (RSD), accuracies from 95 to 108% and extraction recoveries from 60 to 84%. The method was practically free of matrix effects and robust to individual differences in serum composition. Most postmenopausal AD women had extremely low androstenedione concentrations, below 0.14 nmol/l, and median testosterone concentrations of 0.15 nmol/l (interquartile range 0.00–0.41), considerably lower than those of postmenopausal BDs (1.28 nmol/l (0.96–1.64) and 0.65 nmol/l (0.56–1.10) respectively). AD women in fertile years had androstenedione concentrations of 1.18 nmol/l (0.71–1.76) and testosterone concentrations of 0.44 nmol/l (0.22–0.63), approximately half of those found in BDs of corresponding age. Conclusion This LC–MS/MS assay provides highly sensitive and specific assessments of glucocorticoids and androgens with low sample volumes and is suitable for endocrine laboratories and research. Its utility has been

  16. Isotope ratio monitoring LC/MS (IRM-LC/MS): new applications

    International Nuclear Information System (INIS)

    Juchelka, D; Hilkert, A.; Krummen, M.

    2005-01-01

    With the introduction of compound specific isotope analysis by isotope ratio monitoring GC/ MS (IRM-GC/MS) the immediate demand for similar applications using HPLC was created. Many compounds of biological, medical, pharmaceutical and environmental interest are not volatile or too polar. Consequently, they cannot be directly analyzed by gas chromatography. In IRM-GC/MS the carrier is helium, which does not interfere with the essential combust ion step prior to isotope ratio mass spectrometry (IRMS). In opposite the LC mobile phase has inhibited a similar direct conversion up to now. All earlier IRM-LC/MS approaches were based on the removal of the liquid phase prior to combustion risking fractionation of the isotope ratios of the eluted compounds. To avoid such restrictions we developed a new continuous flow concept for the coupling of an HPLC system to the isotope ratio MS for 13 C/ 12C isotope ratio analysis. In the Finnigan LC IsoLink, the liquid phase is not removed from the sample prior to oxidation. The sample is oxidized still in the mobile phase followed by on-line separation of the CO 2 from the liquid phase and transfer into the isotope ratio MS. Therefore, this strategy is based on water and inorganic buffers as mobile phase. The new approach opens up a whole new world in the application of gas isotope ratio mass spectrometry. The 13 C/ 12 C ratio s of organic acids, amino acids, carbohydrates and nucleotides can now be measured. These components typically within a complex matrix are separated by liquid chromatography followed by on-line determination of the isotope ratios. The draw backs of using derivatization and off-line preparation procedures can now be over come. This new technique allow s studying biochemical cycles, running tracer experiments and determining the origin of components. Applications from different scientific areas such as biogeochemistry, molecular biology, and pharmacy as well as authenticity control o f foods will be presented

  17. Cannabinoids determination in oral fluid by SPME-GC/MS and UHPLC-MS/MS and its application on suspected drivers.

    Science.gov (United States)

    Anzillotti, Luca; Castrignanò, Erika; Strano Rossi, Sabina; Chiarotti, Marcello

    2014-12-01

    The confirmation of Δ9-tetrahydrocannabinol (THC) in oral fluid (OF) is an important issue for assessing Driving Under the Influence of Drugs (DUID). The aim of this research was to develop a highly sensitive method with minimal sample pre-treatment suitable for the analysis of small OF volumes (100 μL) for the confirmation of cannabinoids in DUID cases. Two methods were compared for the confirmation of THC in residual OF samples, obtained from a preliminary on-site screening with commercial devices. An ultra high performance LC-MS (UHPLC-MS/MS) method and an SPME-GC/MS method were hence developed. 100 μL of the residual mixture OF/preservative buffer or neat OF was simply added to 10 μL of THC-D3 (1 μg/mL) and submitted to the two different analyses: A - direct injection of 10 μL in UHPLC-MS/MS in positive electrospray ionisation (ESI) mode and B - sampling for 30 min with SPME (100 μm polydimethylsiloxane or PDMS fibre) and direct injection by desorption of the fibre in the GC injection port. The lowest limit of detection (LLOD) of THC was 2 ng/mL in UHPLC-MS/MS and 0.5 ng/mL in SPME-GC/MS. In addition, cannabidiol (CBD) and cannabinol (CBN) could be detected in GC/MS equipment at 2 ng/mL, whilst in UHPLC-MS/MS the LLOD was 20 ng/mL. Both methods were applied to 70 samples coming from roadside tests. By SPME-GC/MS analysis, THC was confirmed in 42 samples, whilst CBD was detected in 21 of them, along with CBN in 14 samples. THC concentrations ranged from traces below the lowest limit of quantification or LLOQ (2 ng/mL) up to 690 ng/mL. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

  18. LC-MS/MS Peptide Mapping with Automated Data Processing for Routine Profiling of N-Glycans in Immunoglobulins

    Science.gov (United States)

    Shah, Bhavana; Jiang, Xinzhao Grace; Chen, Louise; Zhang, Zhongqi

    2014-06-01

    Protein N-Glycan analysis is traditionally performed by high pH anion exchange chromatography (HPAEC), reversed phase liquid chromatography (RPLC), or hydrophilic interaction liquid chromatography (HILIC) on fluorescence-labeled glycans enzymatically released from the glycoprotein. These methods require time-consuming sample preparations and do not provide site-specific glycosylation information. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) peptide mapping is frequently used for protein structural characterization and, as a bonus, can potentially provide glycan profile on each individual glycosylation site. In this work, a recently developed glycopeptide fragmentation model was used for automated identification, based on their MS/MS, of N-glycopeptides from proteolytic digestion of monoclonal antibodies (mAbs). Experimental conditions were optimized to achieve accurate profiling of glycoforms. Glycan profiles obtained from LC-MS/MS peptide mapping were compared with those obtained from HPAEC, RPLC, and HILIC analyses of released glycans for several mAb molecules. Accuracy, reproducibility, and linearity of the LC-MS/MS peptide mapping method for glycan profiling were evaluated. The LC-MS/MS peptide mapping method with fully automated data analysis requires less sample preparation, provides site-specific information, and may serve as an alternative method for routine profiling of N-glycans on immunoglobulins as well as other glycoproteins with simple N-glycans.

  19. A UPLC-MS/MS method for analysis of vancomycin in human cerebrospinal fluid and comparison with the chemiluminescence immunoassay.

    Science.gov (United States)

    Mei, Shenghui; Wang, Jiaqing; Zhu, Leting; Chen, Ruiling; Li, Xingang; Chen, Kai; Chen, Guangqiang; Zhou, Jianxin; Wang, Qiang; Zhao, Zhigang

    2017-08-01

    Vancomycin (VCM) is clinically used in treating patients with postoperative intracranial infections. The cerebrospinal fluid (CSF) concentration of VCM varies greatly among patients. To guide the dosage regimens, monitoring of VCM in CSF is needed. However a method for analysis of VCM in human CSF is lacking. An ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was developed and validated for analysis of VCM in human CSF, and the agreement of UPLC-MS/MS and chemiluminescence immunoassay (CLIA) in the analysis of CSF VCM was evaluated. The ion transitions were m/z 725.5 > 144.1 for VCM and m/z 455.2 > 308.2 for methotrexate (internal standard). The agreement between UPLC-MS/MS and CLIA was evaluated by Bland-Altman plot in 179 samples. The calibration range of the UPLC-MS/MS method was 1-400 mg/L. The inaccuracy and imprecision were -0.69-10.80% and  0.98). The 95% limit of agreement of the ratio of CLIA to UPLC-MS/MS was 61.66-107.40%. Further studies are warranted to confirm the results. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Use of Tricaine Methanesulfonate (MS222) for Euthanasia of Reptiles

    Science.gov (United States)

    Conroy, CJ; Papenfuss, T; Parker, J; Hahn, NE

    2009-01-01

    Tricaine methanesulfonate (MS222) injected into the intracoelomic cavity of reptiles was evaluated as a chemical euthanasia method. Three western fence lizards, 2 desert iguanas, 4 garter snakes, and 6 geckos were euthanized by intracoelomic injection of 250 to 500 mg/kg of 0.7% to 1% sodium-bicarbonate–buffered MS222 solution followed by intracoelomic injection of 0.1 to 1.0 ml unbuffered 50% (v/v) MS222 solution. A simple 2-stage protocol for euthanasia of reptiles by using MS222 is outlined. In addition, the conditions for safe use of MS222 are discussed. MS222 offers an alternative to sodium pentobarbital for euthanasia of reptiles. PMID:19245747

  1. Rapid Quantification of Abscisic Acid by GC-MS/MS for Studies of Abiotic Stress Response.

    Science.gov (United States)

    Verslues, Paul E

    2017-01-01

    Drought and low water potential induce large increases in Abscisic Acid (ABA ) content of plant tissue. This increased ABA content is essential to regulate downstream stress resistance responses; however, the mechanisms regulating ABA accumulation are incompletely known. Thus, the ability to accurately quantify ABA at high throughput and low cost is important for plant stress research. We have combined and modified several previously published protocols to establish a rapid ABA analysis protocol using gas chromatography-tandem mass spectrometry (GC-MS/MS). Derivatization of ABA is performed with (trimethylsilyl)-diazomethane rather than the harder to prepare diazomethane. Sensitivity of the analysis is sufficient that small samples of low water potential treated Arabidopsis thaliana seedlings can be routinely analyzed in reverse genetic studies of putative stress regulators as well as studies of natural variation in ABA accumulation.

  2. Current advances and strategies towards fully automated sample preparation for regulated LC-MS/MS bioanalysis.

    Science.gov (United States)

    Zheng, Naiyu; Jiang, Hao; Zeng, Jianing

    2014-09-01

    Robotic liquid handlers (RLHs) have been widely used in automated sample preparation for liquid chromatography-tandem mass spectrometry (LC-MS/MS) bioanalysis. Automated sample preparation for regulated bioanalysis offers significantly higher assay efficiency, better data quality and potential bioanalytical cost-savings. For RLHs that are used for regulated bioanalysis, there are additional requirements, including 21 CFR Part 11 compliance, software validation, system qualification, calibration verification and proper maintenance. This article reviews recent advances in automated sample preparation for regulated bioanalysis in the last 5 years. Specifically, it covers the following aspects: regulated bioanalysis requirements, recent advances in automation hardware and software development, sample extraction workflow simplification, strategies towards fully automated sample extraction, and best practices in automated sample preparation for regulated bioanalysis.

  3. Quantitation of sweet steviol glycosides by means of a HILIC-MS/MS-SIDA approach.

    Science.gov (United States)

    Well, Caroline; Frank, Oliver; Hofmann, Thomas

    2013-11-27

    Meeting the rising consumer demand for natural food ingredients, steviol glycosides, the sweet principle of Stevia rebaudiana Bertoni (Bertoni), have recently been approved as food additives in the European Union. As regulatory constraints require sensitive methods to analyze the sweet-tasting steviol glycosides in foods and beverages, a HILIC-MS/MS method was developed enabling the accurate and reliable quantitation of the major steviol glycosides stevioside, rebaudiosides A-F, steviolbioside, rubusoside, and dulcoside A by using the corresponding deuterated 16,17-dihydrosteviol glycosides as suitable internal standards. This quantitation not only enables the analysis of the individual steviol glycosides in foods and beverages but also can support the optimization of breeding and postharvest downstream processing of Stevia plants to produce preferentially sweet and least bitter tasting Stevia extracts.

  4. LC-MS/MS Identification of Species-Specific Muscle Peptides in Processed Animal Proteins.

    Science.gov (United States)

    Marchis, Daniela; Altomare, Alessandra; Gili, Marilena; Ostorero, Federica; Khadjavi, Amina; Corona, Cristiano; Ru, Giuseppe; Cappelletti, Benedetta; Gianelli, Silvia; Amadeo, Francesca; Rumio, Cristiano; Carini, Marina; Aldini, Giancarlo; Casalone, Cristina

    2017-12-06

    An innovative analytical strategy has been applied to identify signature peptides able to distinguish among processed animal proteins (PAPs) derived from bovine, pig, fish, and milk products. Proteomics was first used to elucidate the proteome of each source. Starting from the identified proteins and using a funnel based approach, a set of abundant and well characterized peptides with suitable physical-chemical properties (signature peptides) and specific for each source was selected. An on-target LC-ESI-MS/MS method (MRM mode) was set up using standard peptides and was then applied to selectively identify the PAP source and also to distinguish proteins from bovine carcass and milk proteins. We believe that the method described meets the request of the European Commission which has developed a strategy for gradually lifting the "total ban" toward "species to species ban", therefore requiring official methods for species-specific discrimination in feed.

  5. Multiplexed LC-MS/MS analysis of horse plasma proteins to study doping in sport.

    Science.gov (United States)

    Barton, Chris; Beck, Paul; Kay, Richard; Teale, Phil; Roberts, Jane

    2009-06-01

    The development of protein biomarkers for the indirect detection of doping in horse is a potential solution to doping threats such as gene and protein doping. A method for biomarker candidate discovery in horse plasma is presented using targeted analysis of proteotypic peptides from horse proteins. These peptides were first identified in a novel list of the abundant proteins in horse plasma. To monitor these peptides, an LC-MS/MS method using multiple reaction monitoring was developed to study the quantity of 49 proteins in horse plasma in a single run. The method was optimised and validated, and then applied to a population of race-horses to study protein variance within a population. The method was finally applied to longitudinal time courses of horse plasma collected after administration of an anabolic steroid to demonstrate utility for hypothesis-driven discovery of doping biomarker candidates.

  6. Phytochemical Analysis of Pfaffia glomerata Inflorescences by LC-ESI-MS/MS

    Directory of Open Access Journals (Sweden)

    Daniele F. Felipe

    2014-09-01

    Full Text Available Pfaffia glomerata contains high levels of β-ecdysone, which has shown a range of beneficial pharmacological effects. The present study demonstrated that inflorescences of P. glomerata contain other important bioactive compounds in addition to β-ecdysone. The identification of compounds from inflorescences using liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS was performed for the first time. The eight compounds identified were β-ecdysone, flavonoid glycosides such as quercetin-3-O-glucoside, kaempferol-3-O-glucoside and kaempferol-3-O-(6-p-coumaroyl-glucoside, oleanane-type triterpenoid saponins such as ginsenoside Ro and chikusetsusaponin IV, in addition to oleanonic acid and gluconic acid. This study provided information on the phytochemicals contained in P. glomerata inflorescences revealing the potential application of this plant part as raw material for the phytotherapeutic and cosmetic industries.

  7. A Validated, Rapid HPLC-ESI-MS/MS Method for the Determination of Lycopsamine.

    Science.gov (United States)

    Jedlinszki, Nikoletta; Csupor, Dezső

    2015-07-01

    The aim of the present work was to develop and validate an HPLC-MS/MS method for the determination of a major pyrrolizidine alkaloid of comfrey (lycopsamine) in aqueous samples as a basis for the development of a method for the determination of absorption of lycopsamine by human skin. A linear calibration curve was established in the range of 1.32-440 ng. The intraday precision during the 3-day validation period ranged between 0.57 and 2.48% while the interday precision was 1.70% and 1.95% for quality control samples. LOD was 0.014 ng and recovery was above 97%. The lycopsamine content of the samples stored for 9 and 25 days at 22 degrees C, 10 degrees C and -25 degrees C did not vary. These results underline the good repeatability and accuracy of our method and allow the analysis of samples with very low lycopsamine content.

  8. Stars of type MS with evidence of white dwarf companions. [IUE, Main Sequence (MS)

    Science.gov (United States)

    Peery, Benjamin F., Jr.

    1986-01-01

    A search for white dwarf companions of MS-type stars was conducted, using IUE. The overendowments of these stars in typical S-process nuclides suggest that they, like the Ba II stars, may owe their peculiar compositions to earlier mass transfer. Short-wavelength IUE spectra show striking emission line variability in HD35155, HD61913, and 4 Ori; HD35155 and 4 Ori show evidence of white dwarf companions.

  9. Characterization of the Proteome of Theobroma cacao Beans by Nano-UHPLC-ESI MS/MS.

    Science.gov (United States)

    Scollo, Emanuele; Neville, David; Oruna-Concha, M Jose; Trotin, Martine; Cramer, Rainer

    2018-02-01

    Cocoa seed storage proteins play an important role in flavour development as aroma precursors are formed from their degradation during fermentation. Major proteins in the beans of Theobroma cacao are the storage proteins belonging to the vicilin and albumin classes. Although both these classes of proteins have been extensively characterized, there is still limited information on the expression and abundance of other proteins present in cocoa beans. This work is the first attempt to characterize the whole cocoa bean proteome by nano-UHPLC-ESI MS/MS analysis using tryptic digests of cocoa bean protein extracts. The results of this analysis show that >1000 proteins could be identified using a species-specific Theobroma cacao database. The majority of the identified proteins were involved with metabolism and energy. Additionally, a significant number of the identified proteins were linked to protein synthesis and processing. Several proteins were also involved with plant response to stress conditions and defence. Albumin and vicilin storage proteins showed the highest intensity values among all detected proteins, although only seven entries were identified as storage proteins. A comparison of MS/MS data searches carried out against larger non-specific databases confirmed that using a species-specific database can increase the number of identified proteins, and at the same time reduce the number of false positives. The results of this work will be useful in developing tools that can allow the comparison of the proteomic profile of cocoa beans from different genotypes and geographic origins. Data are available via ProteomeXchange with identifier PXD005586. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Measurement of methionine level with the LC-ESI-MS/MS method in schizophrenic patients.

    Science.gov (United States)

    Kulaksizoglu, S; Kulaksizoglu, B; Ellidag, H Y; Eren, E; Yilmaz, N; Baykal, A

    2016-01-01

    The purpose of this study was to evaluate plasma methionine levels by using liquid chromatography electrospray ionization-tandem mass spectroscopy (LC-ESI-MS/MS) in schizophrenic patients. A twelve-point standard graph was drawn, and the recovery rate, the intra-day and inter-day coefficients of variation (CV), the limit of detection (LOD), and the limit of quantification (LOQ) were evaluated. The y and R2 values of the standard graph equation were determined as 0.011x + 0.0179 and 0.9989, respectively, and the graph remained linear until the 200 µmol/l level. The intra-day coefficients of variation of the samples (n = 10) containing 8, 28, and 58 µmol/l methionine were determined as 2.68, 3.10, and 3.79%, respectively; while their inter-day coefficients of variation were determined as 2.98, 3.19, and 3.84%. The LOD and LOQ values were determined as 0.04 and 0.1 µmol/l, respectively, while the mean recovery rates were determined as 101.7 and 99.3%. Plasma methionine values were measured as 21.5 (19.5-24,6) µmol/l for the patient group, 17.8 (16.3-20.1) µmol/l for the control group, and the difference between the two groups was statistically significant (p = 0.03). LC-ESI-MS/MS method represents a fairly sensitive, economic, and rapid analysis that requires very little sample and is suitable for measuring methionine levels in schizophrenic patients.

  11. Determination of Dextromethorphan in Oral Fluid by LC-MS-MS.

    Science.gov (United States)

    Amaratunga, Piyadarsha; Clothier, Morgan; Lorenz Lemberg, Bridget; Lemberg, Dave

    2016-06-01

    Dextromethorphan (DXM) is an antitussive drug found in commonly used nonprescription cold and cough medications. At low doses, DXM is a safe drug that does not produce adverse reactions. However, abuse of DXM has been reported among adolescents and young adults using the drug at higher doses. DXM is not a scheduled drug in the USA, and the primary reason for its abuse is the ease of availability. DXM is available to purchase in the form of over-the-counter cough medications, such as Robitussin(®) and Coricidin(®), or it can be purchased over the Internet in the form of a powder. In this research work, we developed an LC-MS-MS method that can quantify DXM and dextrorphan (DXO) in oral fluid in a high-throughput toxicology laboratory setting. The developed method was validated according to the Scientific Working Group for Forensic Toxicology guidelines. The linear dynamic range was 5-100 ng/mL with a lowest limit of quantitation (LLOQ) of 5.0 ng/mL for DXM and DXO. Overall, the results of the accuracy and the precision values were within the acceptance criteria for both drugs. In addition, selectivity, matrix effect and recovery were calculated for the LC-MS-MS method. Authentic samples (n = 59) were tested to evaluate the applicability of the method. Thirty samples were found to be positive for DXM and DXO and two samples were found to be positive for DXM only. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. UPLC-MS/MS determination of ptaquiloside and pterosin B in preserved natural water.

    Science.gov (United States)

    Clauson-Kaas, Frederik; Hansen, Hans Christian Bruun; Strobel, Bjarne W

    2016-11-01

    The naturally occurring carcinogen ptaquiloside and its degradation product pterosin B are found in water leaching from bracken stands. The objective of this work is to present a new sample preservation method and a fast UPLC-MS/MS method for quantification of ptaquiloside and pterosin B in environmental water samples, employing a novel internal standard. A faster, reliable, and efficient method was developed for isolation of high purity ptaquiloside and pterosin B from plant material for use as analytical standards, with purity verified by 1 H-NMR. The chemical analysis was performed by cleanup and preconcentration of samples with solid phase extraction, before analyte quantification with UPLC-MS/MS. By including gradient elution and optimizing the liquid chromatography mobile phase buffer system, a total run cycle of 5 min was achieved, with method detection limits, including preconcentration, of 8 and 4 ng/L for ptaquiloside and pterosin B, respectively. The use of loganin as internal standard improved repeatability of the determination of both analytes, though it could not be employed for sample preparation. Buffering raw water samples in situ with ammonium acetate to pH ∼5.5 decisively increased sample integrity at realistic transportation and storing conditions prior to extraction. Groundwater samples collected in November 2015 at the shallow water table below a Danish bracken stand were preserved and analyzed using the above methods, and PTA concentrations of 3.8 ± 0.24 μg/L (±sd, n = 3) were found, much higher than previously reported. Graphical abstract Workflow overview of ptaquiloside determination.

  13. Simultaneous quantitation of multiple contraceptive hormones in human serum by LC-MS/MS.

    Science.gov (United States)

    Blue, Steven W; Winchell, Andrea J; Kaucher, Amy V; Lieberman, Rachel A; Gilles, Christopher T; Pyra, Maria N; Heffron, Renee; Hou, Xuanlin; Coombs, Robert W; Nanda, Kavita; Davis, Nicole L; Kourtis, Athena P; Herbeck, Joshua T; Baeten, Jared M; Lingappa, Jairam R; Erikson, David W

    2018-04-01

    The objective was to develop a method to simultaneously quantify five commonly used hormonal contraceptives (HCs) and two endogenous sex steroids by liquid chromatography-tandem triple quadrupole mass spectrometry (LC-MS/MS) and apply this method to human serum samples. We developed a method to simultaneously analyze ethinyl estradiol (EE2), etonogestrel (ENG), levonorgestrel (LNG), medroxyprogesterone acetate (MPA) and norethisterone (NET), along with estradiol (E2) and progesterone (P4), in human serum for a Shimadzu Nexera-LCMS-8050 LC-MS/MS platform. We analyzed serum collected from women self-reporting use of oral contraceptives, contraceptive implants or injectable contraceptives (n=14) and normally cycling women using no HC (n=15) as well as pooled samples from women administered various HCs (ENG, n=6; LNG, n=14; MPA, n=7; NET, n=5). Limits of quantitation were 0.010ng/mL for E2, EE2 and P4; 0.020ng/mL for ENG, LNG and MPA; and 0.040ng/mL for NET. Precisions for all assays, as indicated by coefficient of variation, were less than or equal to 12.1%. Accuracies for all assays were in the range of 95%-108%. Endogenous hormone values obtained from analysis of human serum samples are in agreement with levels previously reported in the literature for normally cycling women as well as for women taking the appropriate HC. We have developed a robust, accurate and sensitive method for simultaneously analyzing commonly used contraceptive steroids and endogenous sex steroids in human serum. This analytical method can be used for quantitating contraceptive steroid levels in women for monitoring systemic exposure to determine drug interactions, nonadherence, misreporting and proper dosing. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Identifying inaccuracy of MS Project using system analysis

    Science.gov (United States)

    Fachrurrazi; Husin, Saiful; Malahayati, Nurul; Irzaidi

    2018-05-01

    The problem encountered in project owner’s financial accounting report is the difference in total project costs of MS Project to the Indonesian Standard (Standard Indonesia Standard / Cost Estimating Standard Book of Indonesia). It is one of the MS Project problems concerning to its cost accuracy, so cost data cannot be used in an integrated way for all project components. This study focuses on finding the causes of inaccuracy of the MS Projects. The aim of this study, which is operationally, are: (i) identifying cost analysis procedures for both current methods (SNI) and MS Project; (ii) identifying cost bias in each element of the cost analysis procedure; and (iii) analysing the cost differences (cost bias) in each element to identify what the cause of inaccuracies in MS Project toward SNI is. The method in this study is comparing for both the system analysis of MS Project and SNI. The results are: (i) MS Project system in Work of Resources element has limitation for two decimal digits only, have led to its inaccuracy. Where the Work of Resources (referred to as effort) in MS Project represents multiplication between the Quantities of Activities and Requirements of resources in SNI; (ii) MS Project and SNI have differences in the costing methods (the cost estimation methods), in which the SNI uses the Quantity-Based Costing (QBC), meanwhile MS Project uses the Time-Based Costing (TBC). Based on this research, we recommend to the contractors who use SNI should make an adjustment for Work of Resources in MS Project (with correction index) so that it can be used in an integrated way to the project owner’s financial accounting system. Further research will conduct for improvement the MS Project as an integrated tool toward all part of the project participant.

  15. Software Tools and Approaches for Compound Identification of LC-MS/MS Data in Metabolomics

    Directory of Open Access Journals (Sweden)

    Ivana Blaženović

    2018-05-01

    Full Text Available The annotation of small molecules remains a major challenge in untargeted mass spectrometry-based metabolomics. We here critically discuss structured elucidation approaches and software that are designed to help during the annotation of unknown compounds. Only by elucidating unknown metabolites first is it possible to biologically interpret complex systems, to map compounds to pathways and to create reliable predictive metabolic models for translational and clinical research. These strategies include the construction and quality of tandem mass spectral databases such as the coalition of MassBank repositories and investigations of MS/MS matching confidence. We present in silico fragmentation tools such as MS-FINDER, CFM-ID, MetFrag, ChemDistiller and CSI:FingerID that can annotate compounds from existing structure databases and that have been used in the CASMI (critical assessment of small molecule identification contests. Furthermore, the use of retention time models from liquid chromatography and the utility of collision cross-section modelling from ion mobility experiments are covered. Workflows and published examples of successfully annotated unknown compounds are included.

  16. Application of LC-ESI-MS-MS for detection of synthetic adulterants in herbal remedies.

    Science.gov (United States)

    Bogusz, Maciej J; Hassan, Huda; Al-Enazi, Eid; Ibrahim, Zuhour; Al-Tufail, Mohammed

    2006-05-03

    Adulteration of allegedly "natural herbal medicines" with undeclared synthetic drugs is a common and dangerous phenomenon of alternative medicine. The purpose of the study was to develop a procedure for detection of most common synthetic adulterants in herbal remedies, using high-pressure liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS-MS). Eighty drugs belonging to various pharmacological classes were included in the study. For most drugs two transitions were monitored, using protonated or deprotonated molecules as precursor ions. The drugs were isolated from herbal remedies using simple methanol extraction. Chromatographic separation was done in gradient of acetonitrile-10 mM ammonium formate buffer (pH 3.0). Drugs tested were grouped in suites, comprising analgesic drugs, antibiotics, antidiabetic drugs, antiepileptic drugs, aphrodisiacs, hormones and anabolic drugs, psychotropic drugs, and weight reducing compounds. These suites were used according to the declared benefits of examined preparations. Limits of detection ranged from 5 pg to 1 ng per injected sample. Drug-free herbal remedy spiked with eight various pharmaceuticals occurring in adulterated herbal preparations was used for internal proficiency testing. The recoveries of spiked drugs ranged from 63 to 100%. The procedure was applied in everyday casework. Several undeclared drugs were identified in "herbal" remedies, like e.g. sildenafil, tadalafil, testosterone, or glibenclamide. Pharmacological properties of detected drugs always corresponded with the claims of the "natural" remedies. The method presents a valuable extension of standard GC-MS screening used for this purpose.

  17. Simultaneous and Sequential MS/MS Scan Combinations and Permutations in a Linear Quadrupole Ion Trap.

    Science.gov (United States)

    Snyder, Dalton T; Szalwinski, Lucas J; Cooks, R Graham

    2017-10-17

    Methods of performing precursor ion scans as well as neutral loss scans in a single linear quadrupole ion trap have recently been described. In this paper we report methodology for performing permutations of MS/MS scan modes, that is, ordered combinations of precursor, product, and neutral loss scans following a single ion injection event. Only particular permutations are allowed; the sequences demonstrated here are (1) multiple precursor ion scans, (2) precursor ion scans followed by a single neutral loss scan, (3) precursor ion scans followed by product ion scans, and (4) segmented neutral loss scans. (5) The common product ion scan can be performed earlier in these sequences, under certain conditions. Simultaneous scans can also be performed. These include multiple precursor ion scans, precursor ion scans with an accompanying neutral loss scan, and multiple neutral loss scans. We argue that the new capability to perform complex simultaneous and sequential MS n operations on single ion populations represents a significant step in increasing the selectivity of mass spectrometry.

  18. Identification and quantitation of new glutamic acid derivatives in soy sauce by UPLC/MS/MS.

    Science.gov (United States)

    Frerot, Eric; Chen, Ting

    2013-10-01

    Glutamic acid is an abundant amino acid that lends a characteristic umami taste to foods. In fermented foods, glutamic acid can be found as a free amino acid formed by proteolysis or as a non-proteolytic derivative formed by microorganisms. The aim of the present study was to identify different structures of glutamic acid derivatives in a typical fermented protein-based food product, soy sauce. An acidic fraction was prepared with anion-exchange solid-phase extraction (SPE) and analyzed by UPLC/MS/MS and UPLC/TOF-MS. α-Glutamyl, γ-glutamyl, and pyroglutamyl dipeptides, as well as lactoyl amino acids, were identified in the acidic fraction of soy sauce. They were chemically synthesized for confirmation of their occurrence and quantified in the selected reaction monitoring (SRM) mode. Pyroglutamyl dipeptides accounted for 770 mg/kg of soy sauce, followed by lactoyl amino acids (135 mg/kg) and γ-glutamyl dipeptides (70 mg/kg). In addition, N-succinoylglutamic acid was identified for the first time in food as a minor compound in soy sauce (5 mg/kg). Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.

  19. LC-MS/MS signal suppression effects in the analysis of pesticides in complex environmental matrices.

    Science.gov (United States)

    Choi, B K; Hercules, D M; Gusev, A I

    2001-02-01

    The application of LC separation and mobile phase additives in addressing LC-MS/MS matrix signal suppression effects for the analysis of pesticides in a complex environmental matrix was investigated. It was shown that signal suppression is most significant for analytes eluting early in the LC-MS analysis. Introduction of different buffers (e.g. ammonium formate, ammonium hydroxide, formic acid) into the LC mobile phase was effective in improving signal correlation between the matrix and standard samples. The signal improvement is dependent on buffer concentration as well as LC separation of the matrix components. The application of LC separation alone was not effective in addressing suppression effects when characterizing complex matrix samples. Overloading of the LC column by matrix components was found to significantly contribute to analyte-matrix co-elution and suppression of signal. This signal suppression effect can be efficiently compensated by 2D LC (LC-LC) separation techniques. The effectiveness of buffers and LC separation in improving signal correlation between standard and matrix samples is discussed.

  20. A novel study of screening and confirmation of modafinil, adrafinil and their metabolite modafinilic acid under EI-GC-MS and ESI-LC-MS-MS ionization.

    Science.gov (United States)

    Dubey, S; Ahi, S; Reddy, I M; Kaur, T; Beotra, A; Jain, S

    2009-12-01

    Adrafinil and modafinil have received wide publicity and have become controversial in the sporting world when several athletes were discovered allegedly using these drugs as doping agents. By acknowledging the facts, the World Anti-Doping Agency (WADA) banned these drugs in sports since 2004. The present study explores the possibility of differentiating adrafinil and modafinil and their major metabolites under electron impact ionization in gas chromatograph-mass spectrometer (GC-MSD) and electrospray ionization in liquid chromatograph-mass spectrometer (LC-MS/MS) by studying the fragmentation pattern of these drugs. Adrafinil, modafinil and their major metabolite, modafinilic acid were analyzed on EI-GC-MSD and ESI-LC-MS/MS using various individual parameters on both the instruments. The analytical technique and equipment used in the analysis were an Agilent 6890N GC with 5973 mass selective detector for the GC-MSD analysis and an Agilent 1100 HPLC with API-3200 Triple quadrupole mass spectrometer for the LC-MS/MS analysis. Validation of both methods was performed using six replicates at different concentrations. The results show that adrafinil, modafinil and their major metabolite modafinilic acid could be detected as a single artifact without differentiation under EI-GC-MSD analysis. However, all drugs could be detected and differentiated under ESI-LCMS/MS analysis without any artifaction. The GC-MSD analysis gives a single artifact for both the drugs without differentiation and thus can be used as a marker for screening purposes. Further, the Multiple Reaction Monitoring (MRM) method developed under LC-MS/MS is fit for the purpose for confirmation of suspicious samples in routine sports testing and in forensic and clinical analysis.

  1. Survival and mortality rates among Danes with MS

    DEFF Research Database (Denmark)

    Brønnum-Hansen, H; Stenager, Egon; Hansen, Thomas

    2006-01-01

    Long-term survival and trends in overall and cause-specific excess mortality among people with MS have been studied using the Danish Multiple Sclerosis Registry, which contains information about all Danish MS patients since the mid-20th Century. A total of 4254 deaths among approximately 10......,000 people with MS, representing more than 200,000 person-years of observation, have been analysed. Overall, mortality was almost three times higher and life expectancy 10 years less among people with MS than for the general population. However, excess mortality has declined significantly since 1950....

  2. Maryland magnetic fusion research program: MS speromak

    International Nuclear Information System (INIS)

    DeSilva, A.W.; Goldenbaum, G.C.; Griem, H.R.

    1989-07-01

    The main theme of our present experimentation on MS is to prolong the spheromak lifetime. This research has been concerned with such topics as passive MHD stabilization coils, impurity control and increased energy storage. At the present time the longest lived plasmas appear to be line tied to the liner or reversal coils. The natural consequence of having net flux outside the separatrix and a resistive plasma is that the plasma shrinks in time. At some point in time the plasma is far enough from the liner, or stabilization coils, that it becomes unstable. If we increase the bias field so as to move the separatrix further inside the liner, the plasma becomes unstable earlier as the separatrix moves to a smaller radius in a shorter time than if it starts out outside the liner. We have tried to circumvent this behavior with various configurations of passive conductors used as stabilizing elements. In this paper, we detail some of the machine modifications that have been tried in attempts to produce a stable, long-lived plasma

  3. Short Communication: Testosterone Measured with an Automatic Immunoassay Compares Reasonbly Well to Results Obtained by LC-MS/MS

    DEFF Research Database (Denmark)

    Knudsen, Cindy Søndersø; Højskov, Carsten Schriver; Møller, Holger Jon

    2016-01-01

    Background: Previous studies have reported problems measuring testosterone with immunological assays. Here we explore an automatic second generation immunoassay compared to a LC-MS/MS method. Methods: We collected blood samples from 76 women and measured testosterone, progesterone, gender...... hormonebinding globulin (SHBG), and albumin employing Cobas e601/c501. Testosterone, androstenedione (andro), dehydroepiandrosterone sulphate (DHEAS), and 17-hydroxyprogesterone (17-OHP) concentrations were measured employing LC-MS/MS. We evaluated the difference between testosterone measured by the two methods...... and examined the potential interference from the selected steroids and bindings proteins. Results: Testosterone concentrations measured by the two methods yielded: Cobas e601 = 1.240 x (LC-MS/MS) - 0.197, r = 0.84, for testosterone concentrations between 0.22 - 4.9 nmol/L. A positive correlation was observed...

  4. Structure Annotation and Quantification of Wheat Seed Oxidized Lipids by High-Resolution LC-MS/MS.

    Science.gov (United States)

    Riewe, David; Wiebach, Janine; Altmann, Thomas

    2017-10-01

    Lipid oxidation is a process ubiquitous in life, but the direct and comprehensive analysis of oxidized lipids has been limited by available analytical methods. We applied high-resolution liquid chromatography-mass spectrometry (LC-MS) and tandem mass spectrometry (MS/MS) to quantify oxidized lipids (glycerides, fatty acids, phospholipids, lysophospholipids, and galactolipids) and implemented a platform-independent high-throughput-amenable analysis pipeline for the high-confidence annotation and acyl composition analysis of oxidized lipids. Lipid contents of 90 different naturally aged wheat ( Triticum aestivum ) seed stocks were quantified in an untargeted high-resolution LC-MS experiment, resulting in 18,556 quantitative mass-to-charge ratio features. In a posthoc liquid chromatography-tandem mass spectrometry experiment, high-resolution MS/MS spectra (5 mD accuracy) were recorded for 8,957 out of 12,080 putatively monoisotopic features of the LC-MS data set. A total of 353 nonoxidized and 559 oxidized lipids with up to four additional oxygen atoms were annotated based on the accurate mass recordings (1.5 ppm tolerance) of the LC-MS data set and filtering procedures. MS/MS spectra available for 828 of these annotations were analyzed by translating experimentally known fragmentation rules of lipids into the fragmentation of oxidized lipids. This led to the identification of 259 nonoxidized and 365 oxidized lipids by both accurate mass and MS/MS spectra and to the determination of acyl compositions for 221 nonoxidized and 295 oxidized lipids. Analysis of 15-year aged wheat seeds revealed increased lipid oxidation and hydrolysis in seeds stored in ambient versus cold conditions. © 2017 The author(s). All Rights Reserved.

  5. Time correlation between mononucleosis and initial symptoms of MS

    Science.gov (United States)

    Endriz, John; Ho, Peggy P.

    2017-01-01

    Objective: To determine the average age of MS onset vs the age at which Epstein-Barr infection has previously occurred and stratify this analysis by sex and the blood level of Epstein-Barr nuclear antigen 1 (EBNA1) antibody. Methods: Using infectious mononucleosis (IM) as a temporal marker in data from the Swedish epidemiologic investigation of MS, 259 adult IM/MS cases were identified and then augmented to account for “missing” childhood data so that the average age of MS onset could be determined for cases binned by age of IM (as stratified by sex and EBNA1 titer level). Results: Mean age of IM vs mean age of MS reveals a positive time correlation for all IM ages (from ∼5 to ∼30 years), with IM-to-MS delay decreasing with increased age. When bifurcated by sex or EBNA1 blood titer levels, males and high-titer subpopulations show even stronger positive time correlation, while females and low-titer populations show negative time correlation in early childhood (long IM/MS delay). The correlation becomes positive in females beyond puberty. Conclusions: IM/MS time correlation implies causality if IM is time random. Alternative confounding models seem implausible, in light of constraints imposed by time-invariant delay observed here. Childhood infection with Epstein-Barr virus (EBV) in females and/or those genetically prone to low EBNA1 blood titers will develop MS slowly. Males and/or high EBNA1-prone develop MS more rapidly following IM infection at all ages. For all, postpubescent EBV infection is critical for the initiation and rapid development of MS. PMID:28271078

  6. Chemical characterization of Azadirachta indica grafted on Melia azedarach and analyses of azadirachtin by HPLC-MS-MS (SRM) and meliatoxins by MALDI-MS.

    Science.gov (United States)

    Forim, Moacir Rossi; Cornélio, Vivian Estevam; da Silva, M Fátima das G F; Rodrigues-Filho, Edson; Fernandes, João B; Vieira, Paulo C; Matinez, Sueli Souza; Napolitano, Michael P; Yost, Richard A

    2010-01-01

    Melia azedarach adapted to cool climates was selected as rootstocks for vegetative propagation of Azadirachta indica. Cleft grafting of A. indica on M. azedarach rootstock showed excellent survival. Little is known about the chemistry of grafting. The roots, stems, leaves and seeds of this graft were examined in order to verify if grafted A. indica would produce limonoids different from those found in non-grafted plants. Intact matured fruits were also studied to verify if they were free of meliatoxins. After successive chromatographic separations the extracts afforded several limonoids. HPLC-MS/MS and MALDI-MS were used to develop sensitive methods for detecting azadirachtin on all aerial parts of this graft and meliatoxins in fruits, respectively. The stem afforded the limonoid salannin, which was previously found in the oil seeds of A. indica. Salannin is also found in the root bark of M. azedarach. Thus, the finding of salannin in this study suggests that it could have been translocated from the M. azedarach rootstock to the A. indica graft. HPLC-MS/MS analyses showed that azadirachtin was present in all parts of the fruits, stem, flowers and root, but absent in the leaves. The results of MALDI-MS analyses confirmed the absence of meliatoxins in graft fruits. This study showed that A. indica grafted onto M. azedarach rootstock produces azadirachtin, and also that its fruits are free of meliatoxins from rootstocks, confirming that this graft forms an excellent basis for breeding vigorous Neem trees in cooler regions.

  7. Fundamental and applied measurements in ICP MS

    International Nuclear Information System (INIS)

    Carter, Julian Robert

    2002-01-01

    Fundamental and applied aspects of ICP-MS have been investigated to gain an increased understanding of the technique and improve on its analytical capabilities. Dissociation temperatures of polyatomic ions were calculated using a double-focusing sector instrument, to obtain more reliable mass spectral data with controlled vapour introduction via a Dreschel bottle to allow accurate calculation of the ingredients in the plasma. The equilibrium temperature for the plasma, operated at 1280 W calculated using CO + and C 2 + as the thermometric probes, was c.a. 5800 - 7400 K, while using ArO + and ArC + as the thermometric probes the temperature calculated was c.a. 2000 - 7000 K. Calculated dissociation temperatures were used to elucidate the site of formation of these ions. Results confirmed that strongly bound ions such as CO + and C 2 + were formed in the plasma whereas weakly bound ions such as ArO + and ArC + were formed in the interface region due to gross deviation of the calculated temperatures from those expected for a system in thermal equilibrium. The use of helium gas in a hexapole collision cell attenuated the signals of ArH + Ar + , ArO + , ArC + , ArCl + and Ar 2 + allowing improved determination of 39 K + , 40 Ca + , 56 Fe + , 52 Cr + , 75 As + and 80 Se + in standard solutions. The use of the hexapole collision cell also resulted in an enhancement of analyte signals due to the thermalisation of the ion beam. The ion kinetic energy of ions sampled from the plasma and those sampled from the skimmer cone were determined using a modified lens stack to assess the significance for memory effects of material deposited on the skimmer cone. The most probable kinetic energy of Be + ions sampled from the skimmer cone was found to be 2.4 eV, which was considerably lower than the most probable kinetic energy of Be + ions sampled from the plasma, which was found to be 9.5 eV. The low kinetic energy of the ions deposited on the skimmer cone means they will only

  8. Fundamental and applied measurements in ICP MS

    Energy Technology Data Exchange (ETDEWEB)

    Carter, Julian Robert

    2002-07-01

    Fundamental and applied aspects of ICP-MS have been investigated to gain an increased understanding of the technique and improve on its analytical capabilities. Dissociation temperatures of polyatomic ions were calculated using a double-focusing sector instrument, to obtain more reliable mass spectral data with controlled vapour introduction via a Dreschel bottle to allow accurate calculation of the ingredients in the plasma. The equilibrium temperature for the plasma, operated at 1280 W calculated using CO{sup +} and C{sub 2}{sup +} as the thermometric probes, was c.a. 5800 - 7400 K, while using ArO{sup +} and ArC{sup +} as the thermometric probes the temperature calculated was c.a. 2000 - 7000 K. Calculated dissociation temperatures were used to elucidate the site of formation of these ions. Results confirmed that strongly bound ions such as CO{sup +} and C{sub 2}{sup +} were formed in the plasma whereas weakly bound ions such as ArO{sup +} and ArC{sup +} were formed in the interface region due to gross deviation of the calculated temperatures from those expected for a system in thermal equilibrium. The use of helium gas in a hexapole collision cell attenuated the signals of ArH{sup +} Ar{sup +}, ArO{sup +}, ArC{sup +}, ArCl{sup +} and Ar{sub 2}{sup +} allowing improved determination of {sup 39}K{sup +}, {sup 40}Ca{sup +}, {sup 56}Fe{sup +}, {sup 52}Cr{sup +}, {sup 75}As{sup +} and {sup 80}Se{sup +} in standard solutions. The use of the hexapole collision cell also resulted in an enhancement of analyte signals due to the thermalisation of the ion beam. The ion kinetic energy of ions sampled from the plasma and those sampled from the skimmer cone were determined using a modified lens stack to assess the significance for memory effects of material deposited on the skimmer cone. The most probable kinetic energy of Be{sup +} ions sampled from the skimmer cone was found to be 2.4 eV, which was considerably lower than the most probable kinetic energy of Be{sup +} ions

  9. The case of Ms B: suicide's slippery slope?

    Science.gov (United States)

    Keown, J

    2002-08-01

    In the case of Ms B, the High Court ruled that as Ms B was a competent adult patient, her doctors acted unlawfully in overriding her refusal of life-preserving ventilation. This commentary considers whether this case supports the proposition that in English law the right to refuse treatment extends even to refusals which are clearly suicidal.

  10. The identification of anaerobic bacteria using MALDI-TOF MS

    NARCIS (Netherlands)

    Veloo, A. C. M.; Welling, G. W.; Degener, J. E.

    Matrix Assisted Laser Desorption and Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) has gained more and more popularity for the identification of bacteria. Several studies show that bacterial diagnosticis is being revolutionized by the application of MALDI-TOF MS. For anaerobic bacteria,

  11. The Ms. Stereotype Revisited: Implicit and Explicit Facets

    Science.gov (United States)

    Malcolmson, Kelly A.; Sinclair, Lisa

    2007-01-01

    Implicit and explicit stereotypes toward the title Ms. were examined. Participants read a short description of a target person whose title of address varied (Ms., Mrs., Miss, Mr.). They then rated the person on agentic and communal traits and completed an Implicit Association Test. Replicating earlier research (Dion, 1987), at an explicit level,…

  12. Teaching Bibliometric Analysis and MS/DOS Commands.

    Science.gov (United States)

    Dou, Henri; And Others

    1988-01-01

    Outlines the steps involved in bibliometric studies, and demonstrates the ability to execute simple studies on microcomputers by downloading files using only the capability of MS/DOS. Detailed illustrations of the MS/DOS commands used are provided. (eight references) (CLB)

  13. Determination of Impurities of Atrazine by HPLP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Canping, Pan [Department of Applied Chemistry, China Agricultural University Beijing (China)

    2009-07-15

    The determination of the main impurities of the herbicide atrazine by GC/FID, GC/MS and LC/MS is described. The most relevant technical impurities were synthesized and characterized by IR and UV spectroscopy as well. The impurity profiles of different technical grade formulated products were tested and the typical impurities identified. (author)

  14. New application and future of ICP-MS

    International Nuclear Information System (INIS)

    Masuda, Kimihiko

    1994-01-01

    By ICP-MS, since high sensibility, multi-element rapid analysis and isotope ratio analysis can be carried out, the position as the analysis for ultra-minute amount of elements has been established. Further recently, sample feeder system has been developed, and the multi-collector type device for the purpose of high resolution type isotope ratio analysis has appeared, so the range of its application is spreading more and more. In this report, the examples of application which were able to be attained accompanying the development of these devices are introduced, and the development of the ICP-MS hereafter is described. At present, about 1000 apparatuses are in operation in the world, and the application spread to the fields of semiconductors and materials, earth science, environment, atomic energy and so on. The ICP-MS was developed for the purpose of easily carrying out spectral analysis with high sensibility by using argon ICP as the ion source and doing ion detection which is more efficient than light detection, and has lower background. The progress and the present status of the ICP-MS are reported. As the latest examples of application of the ICP-MS, the analysis of iron by quadrupole type ICP-MS, the small region measurement of solids by laser abrasion, ultra-minute amount analysis by high resolution ICP-MS, the isotope ratio measurement of lead by multi-collector type ICP-MS are reported. (K.I.)

  15. Long-term effects of childbirth in MS

    NARCIS (Netherlands)

    D'hooghe, M.B.; Nagels, G.; Uitdehaag, B.M.J.

    2010-01-01

    Background: The uncertainty about long-term effects of childbirth presents MS patients with dilemmas. Methods: Based on clinical data of 330 female MS patients, the long-term effects of childbirth were analysed, using a cross-sectional study design. Four groups of patients were distinguished: (1)

  16. Multiple sclerosis (MS) for the urologist: What should urologists know about MS?

    Science.gov (United States)

    Aharony, Shachar; Lam, Ornella; Lapierre, Yves; Corcos, Jacques

    2016-02-01

    Multiple sclerosis (MS) is a unique central nervous system (CNS) inflammatory disease with a broad spectrum of clinical presentations, which are time- and disease progression-related. It usually affects young adults, with a female predominance of 3:1. Men are more likely to develop symptoms at a slightly older age with a more progressive disease course. Diagnosis relies on a combination of clinical, radiological, and laboratory investigations, with a central role of magnetic resonance imaging (MRI). Although the exact etiology is still obscure, the leading hypothesis behind MS relapses is acute inflammatory attacks on CNS myelin and axons. This complex process involves B and T cells together with macrophages and microglia. Genetic and environmental factors are thought to be major contributors to the disease's evolution. MS therapies consist of long-term (immunomodulatory) management, focusing on disease modification, and short-term symptomatic control. Symptomatic treatment includes pharmacological and non-pharmacological methods to protect function and restore quality of life (QoL). The introduction and development of disease-modifying medications provide opportunities to change the face of this disease, enhancing QoL over the long-term. Interferon (INF) and Glatiramer acetate (GLAT) represent first line medications with limited effect and relatively fair safety profile. Newer medications with improved efficacy along with a more hazardous side effect profile are now considered second line therapy. The present review summarizes current knowledge of this frequent disease. Urologists must acquire a deeper understanding for better integration of practice recommendations. © 2015 Wiley Periodicals, Inc.

  17. Quantitative analysis of oxytetracycline and its impurities by LC-MS-MS

    DEFF Research Database (Denmark)

    Lykkeberg, Anne Kruse; Halling-Sørensen, Bent; Cornett, Claus

    2004-01-01

    A liquid chromatographic-tandem mass spectrometric method using an Xterra MS C(18) chromatographic column ( 100 mm x 2.1 mm i.d., 3.5microm) that allows complete separation of oxytetracycline (OTC) and the impurities: 4-epi-oxytetracycline (EOTC), tetracycline (TC), 4-epi-tetracycline (ETC), 2......-acetyl-2-decarboxamido-oxytetracycline (ADOTC), alpha-apo-oxytetracycline (alpha-AOTC) and beta-apo-oxytetracycline (beta-AOTC) was developed. Gradient elution was used and calibration curves were obtained using the scan mode selected reaction monitoring (SRM). Acceptable correlations were obtained...

  18. Determination of Scopolamine in Human Saliva Using Solid Phase Extraction and LC/MS/MS

    Science.gov (United States)

    Wang, Zuwei; Vaksman, Zalman; Boyd, Jason; Putcha, Lakshmi

    2007-01-01

    Purpose: Scopolamine is the preferred treatment for motion sickness during space flight because of its quick onset of action, short half-life and favorable side-effect profile. The dose administered depends on the mode of administration and usually ranges between 0.1 and 0.8 mg. Such small doses make it difficult to detect concentrations of scopolamine in biological fluids by using conventional HPLC methods. To measure scopolamine in saliva and thereby to evaluate the pharmacokinetics of scopolamine, we developed an LC/MS/MS method using off-line solid phase extraction. Method: Samples (0.5mL) were loaded onto Waters Oasis HLB co-polymer cartridges (10 mg, 1 mL) and eluted with 0.5 mL methanol without evaporation and reconstitution. HPLC separation of the eluted sample was performed using an Agilent Zorbax SB-CN column (50 x 2.1 mm) at a flow rate of 0.2 mL/min for 4 minutes. The mobile phase for separation was 90:10 (v/v) methanol: ammonium acetate (2 mM) in water, pH 5.0 +/- 0.1. Concentrations of scopolamine were determined using a Micromass Quattro Micro(TM) mass spectrometer with electrospray ionization (ESI). ESI mass spectra were acquired in positive ion mode with multiple reaction monitoring for the determination of scopolamine m/z = 304.2 yields 138.1 and internal standard (IS) hyoscyamine m/z = 290.2 yields 124.1. Results: The method is rapid, reproducible, specific and has the following parameters: scopolamine and the IS are eluted at 1.7 and 3.2 min respectively. The linear range is 50-5000 pg/mL for scopolamine in saliva with correlation coefficients > 0.99 with a CV < 0.5 %. The intra-day and inter-day CVs are < 15 % for quality control samples with concentrations of 75, 300, 750 and 3000 pg/mL of scopolamine in human saliva. Conclusion: Solid phase extraction allows more rapid sample preparation and greater precision than liquid extraction. Furthermore, we increased the sensitivity and specificity by adjusting the LC mobile phase and using an MS/MS

  19. Organization of GC/MS and LC/MS metabolomics data into chemical libraries

    Directory of Open Access Journals (Sweden)

    DeHaven Corey D

    2010-10-01

    Full Text Available Abstract Background Metabolomics experiments involve generating and comparing small molecule (metabolite profiles from complex mixture samples to identify those metabolites that are modulated in altered states (e.g., disease, drug treatment, toxin exposure. One non-targeted metabolomics approach attempts to identify and interrogate all small molecules in a sample using GC or LC separation followed by MS or MSn detection. Analysis of the resulting large, multifaceted data sets to rapidly and accurately identify the metabolites is a challenging task that relies on the availability of chemical libraries of metabolite spectral signatures. A method for analyzing spectrometry data to identify and Quantify Individual Components in a Sample, (QUICS, enables generation of chemical library entries from known standards and, importantly, from unknown metabolites present in experimental samples but without a corresponding library entry. This method accounts for all ions in a sample spectrum, performs library matches, and allows review of the data to quality check library entries. The QUICS method identifies ions related to any given metabolite by correlating ion data across the complete set of experimental samples, thus revealing subtle spectral trends that may not be evident when viewing individual samples and are likely to be indicative of the presence of one or more otherwise obscured metabolites. Results LC-MS/MS or GC-MS data from 33 liver samples were analyzed simultaneously which exploited the inherent biological diversity of the samples and the largely non-covariant chemical nature of the metabolites when viewed over multiple samples. Ions were partitioned by both retention time (RT and covariance which grouped ions from a single common underlying metabolite. This approach benefitted from using mass, time and intensity data in aggregate over the entire sample set to reject outliers and noise thereby producing higher quality chemical identities. The

  20. Discovery of 4ms and 7 MS Pulsars in M15 (F & H)

    Science.gov (United States)

    Middleditch, J.

    1992-12-01

    Observations of M15 taken during Oct. 23-Nov. 1 1991 with the Arecibo 305-m telescope at 430 MHz, which were analyzed using 2-billion point Fourier transforms on supercomputers at Los Alamos National Laboratory, reveal two new ms pulsars in the globular cluster, M15. The sixth and fastest yet discovered in this cluster, M15F, has a spin rate of 248.3 Hz, while the eighth and latest to be discovered in this cluster has a spin rate of 148.3 Hz, the only one known so far in the frequency interval of 100-200 Hz. Further details and implications of these discoveries will be discussed.

  1. Profiling the Oxylipin and Endocannabinoid Metabolome by UPLC-ESI-MS/MS in Human Plasma to Monitor Postprandial Inflammation.

    Science.gov (United States)

    Gouveia-Figueira, Sandra; Späth, Jana; Zivkovic, Angela M; Nording, Malin L

    2015-01-01

    Bioactive lipids, including oxylipins, endocannabinoids, and related compounds may function as specific biochemical markers of certain aspects of inflammation. However, the postprandial responsiveness of these compounds is largely unknown; therefore, changes in the circulating oxylipin and endocannabinoid metabolome in response to a challenge meal were investigated at six occasions in a subject who freely modified her usual diet. The dietary change, and especially the challenge meal itself, represented a modification of precursor fatty acid status, with expectedly subtle effects on bioactive lipid levels. To detect even the slightest alteration, highly sensitive ultra-performance liquid chromatography (UPLC) coupled to electrospray ionization (ESI) tandem mass spectrometry (MS/MS) methods for bioactive lipid profiling was employed. A previously validated UPLC-ESI-MS/MS method for profiling the endocannabinoid metabolome was used, while validation of an UPLC-ESI-MS/MS method for oxylipin analysis was performed with acceptable outcomes for a majority of the parameters according to the US Food and Drug Administration guidelines for linearity (0.9938 metabolome, caused by changes in diet and ii) responsiveness to a challenge meal for a subset of the oxylipin and endocannabinoid metabolome. To summarize, we have shown proof-of-concept of our UPLC-ESI-MS/MS bioactive lipid protocols for the purpose of monitoring subtle shifts, and thereby useful to address lipid-mediated postprandial inflammation.

  2. Direct, rapid quantitative analyses of BVOCs using SIFT-MS and PTR-MS obviating sample collection

    Czech Academy of Sciences Publication Activity Database

    Smith, D.; Španěl, Patrik

    2011-01-01

    Roč. 30, č. 7 (2011), s. 945-959 ISSN 0165-9936 Institutional research plan: CEZ:AV0Z40400503 Keywords : SIFT-MS * PTR-MS * Absolute quantification Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 6.273, year: 2011

  3. In vivo Phosphoproteome of Human Skeletal Muscle Revealed by Phosphopeptide Enrichment and HPLC-ESI-MS/MS

    DEFF Research Database (Denmark)

    Højlund, Kurt; Bowen, Benjamin P; Hwang, Hyonson

    2009-01-01

    volunteers. Trypsin digestion of 3-5 mg human skeletal muscle protein was followed by phosphopeptide enrichment using SCX and TiO2. The resulting phosphopeptides were analyzed by HPLC-ESI-MS/MS. Using this unbiased approach, we identified 306 distinct in vivo phosphorylation sites in 127 proteins, including...

  4. Simultaneous quantitation of sphingoid bases by UPLC-ESI-MS/MS with identical (13)C-encoded internal standards

    NARCIS (Netherlands)

    Mirzaian, M.; Wisse, P.; Ferraz, M. J.; Marques, A. R. A.; Gaspar, P.; Oussoren, S. V.; Kytidou, K.; Codée, J. D. C.; van der Marel, G.; Overkleeft, H. S.; Aerts, J. M.

    2017-01-01

    Free sphingoid bases (lysosphingolipids) of primary storage sphingolipids are increased in tissues and plasma of several sphingolipidoses. As shown earlier by us, sphingoid bases can be accurately quantified using UPLC-ESI-MS/MS, particularly in combination with identical (13)C-encoded internal

  5. Comparison of 7 Published LC-MS/MS Methods for the Simultaneous Measurement of Testosterone, Androstenedione, and Dehydroepiandrosterone in Serum

    DEFF Research Database (Denmark)

    Büttler, Rahel M; Martens, Frans; Fanelli, Flaminia

    2015-01-01

    , and dehydroepiandrosterone (DHEA). METHODS: We used 7 published LC-MS/MS methods to analyze in duplicate 55 random samples from both men and women. We performed Passing-Bablok regression analysis and calculated Pearson correlation coefficients to assess the agreement of the methods investigated with the median concentration...

  6. Structural Feature Ions for Distinguishing N- and O-Linked Glycan Isomers by LC-ESI-IT MS/MS

    Science.gov (United States)

    Everest-Dass, Arun V.; Abrahams, Jodie L.; Kolarich, Daniel; Packer, Nicolle H.; Campbell, Matthew P.

    2013-06-01

    Glycomics is the comprehensive study of glycan expression in an organism, cell, or tissue that relies on effective analytical technologies to understand glycan structure-function relationships. Owing to the macro- and micro-heterogeneity of oligosaccharides, detailed structure characterization has required an orthogonal approach, such as a combination of specific exoglycosidase digestions, LC-MS/MS, and the development of bioinformatic resources to comprehensively profile a complex biological sample. Liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS/MS) has emerged as a key tool in the structural analysis of oligosaccharides because of its high sensitivity, resolution, and robustness. Here, we present a strategy that uses LC-ESI-MS/MS to characterize over 200 N- and O-glycans from human saliva glycoproteins, complemented by sequential exoglycosidase treatment, to further verify the annotated glycan structures. Fragment-specific substructure diagnostic ions were collated from an extensive screen of the literature available on the detailed structural characterization of oligosaccharides and, together with other specific glycan structure feature ions derived from cross-ring and glycosidic-linkage fragmentation, were used to characterize the glycans and differentiate isomers. The availability of such annotated mass spectrometric fragmentation spectral libraries of glycan structures, together with such substructure diagnostic ions, will be key inputs for the future development of the automated elucidation of oligosaccharide structures from MS/MS data.

  7. Detecting pM concentrations of prostaglandins in cell culture supernatants by capillary SCX-LC-MS/MS

    DEFF Research Database (Denmark)

    Dahl, Sandra Rinne; Kleiveland, Charlotte Ramstad; Kassem, Moustapha

    2008-01-01

    A highly sensitive, improved online strong cation exchange (SCX)--RP capillary liquid chromatographic (cLC) method with IT mass spectrometric (IT-MS/MS) detection for the simultaneous determination of prostaglandin (PG)A(1), PGD(2), PGE(1), PGE(2), PGF(2alpha), 8-iso-(8i)PGF(2alpha), 6-keto-(6k...

  8. Metabolomic and elemental analysis of camel and bovine urine by GC-MS and ICP-MS.

    Science.gov (United States)

    Ahamad, Syed Rizwan; Alhaider, Abdul Qader; Raish, Mohammad; Shakeel, Faiyaz

    2017-01-01

    Recent studies from the author's laboratory indicated that camel urine possesses antiplatelet activity and anti-cancer activity which is not present in bovine urine. The objective of this study is to compare the volatile and elemental components of bovine and camel urine using GC-MS and ICP-MS analysis. We are interested to know the component that performs these biological activities. The freeze dried urine was dissolved in dichloromethane and then derivatization process followed by using BSTFA for GC-MS analysis. Thirty different compounds were analyzed by the derivatization process in full scan mode. For ICP-MS analysis twenty eight important elements were analyzed in both bovine and camel urine. The results of GC-MS and ICP-MS analysis showed marked difference in the urinary metabolites. GC-MS evaluation of camel urine finds a lot of products of metabolism like benzene propanoic acid derivatives, fatty acid derivatives, amino acid derivatives, sugars, prostaglandins and canavanine. Several research reports reveal the metabolomics studies on camel urine but none of them completely reported the pharmacology related metabolomics. The present data of GC-MS suggest and support the previous studies and activities related to camel urine.

  9. Simultaneous Determination of Cyclosporine A, Tacrolimus, Sirolimus, and Everolimus in Whole-Blood Samples by LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Mustafa Karapirli

    2012-01-01

    Full Text Available Objectives. Cyclosporine A (CyA, tacrolimus (TRL, sirolimus (SIR, and everolimus (RAD are immunosuppressive drugs frequently used in organ transplantation. Our aim was to confirm a robust sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS method for determination of CyA, TRL, SIR, and RAD in whole-blood samples. Materials and Methods. We used an integrated online solid-phase extraction-LC-MS/MS system and atmospheric pressure ionization tandem mass spectrometry (API-MS/MS in the multiple reaction monitoring (MRM detection mode. CyA, TRL, SIR, and RAD were simultaneously analyzed in whole blood treated with precipitation reagent taken from transplant patients. Results. System performance parameters were suitable for using this method as a high-throughput technique in clinical practice. The high concentration of one analyte in the sample did not affect the concentration of other analytes. Total analytical time was 2.5 min, and retention times of all analytes were shorter than 2 minutes. Conclusion. This LC-MS/MS method can be preferable for therapeutic drug monitoring of these immunosuppressive drugs (CyA, TRL, SRL, and RAD in whole blood. Sample preparation was too short and simple in this method, and it permits robust, rapid, sensitive, selective, and simultaneous determination of these drugs.

  10. A comparison between DART-MS and DSA-MS in the forensic analysis of writing inks.

    Science.gov (United States)

    Drury, Nicholas; Ramotowski, Robert; Moini, Mehdi

    2018-05-23

    Ambient ionization mass spectrometry is gaining momentum in forensic science laboratories because of its high speed of analysis, minimal sample preparation, and information-rich results. One such application of ambient ionization methodology includes the analysis of writing inks from questioned documents where colorants of interest may not be soluble in common solvents, rendering thin layer chromatography (TLC) and separation-mass spectrometry methods such as LC/MS (-MS) impractical. Ambient ionization mass spectrometry uses a variety of ionization techniques such as penning ionization in Direct Analysis in Real Time (DART), and atmospheric pressure chemical ionization in Direct Sample Analysis (DSA), and electrospray ionization in Desorption Electrospray Ionization (DESI). In this manuscript, two of the commonly used ambient ionization techniques are compared: Perkin Elmer DSA-MS and IonSense DART in conjunction with a JEOL AccuTOF MS. Both technologies were equally successful in analyzing writing inks and produced similar spectra. DSA-MS produced less background signal likely because of its closed source configuration; however, the open source configuration of DART-MS provided more flexibility for sample positioning for optimum sensitivity and thereby allowing smaller piece of paper containing writing ink to be analyzed. Under these conditions, the minimum sample required for DART-MS was 1mm strokes of ink on paper, whereas DSA-MS required a minimum of 3mm. Moreover, both techniques showed comparable repeatability. Evaluation of the analytical figures of merit, including sensitivity, linear dynamic range, and repeatability, for DSA-MS and DART-MS analysis is provided. To the forensic context of the technique, DART-MS was applied to the analysis of United States Secret Service ink samples directly on a sampling mesh, and the results were compared with DSA-MS of the same inks on paper. Unlike analysis using separation mass spectrometry, which requires sample

  11. Carotenoid composition of jackfruit (Artocarpus heterophyllus), determined by HPLC-PDA-MS/MS.

    Science.gov (United States)

    de Faria, A F; de Rosso, V V; Mercadante, A Z

    2009-06-01

    Carotenoids are pigments responsible for the yellow-reddish color of many foods and are related to important functions and physiological actions, preventing several chronic-degenerative diseases. The objective of this study was to confirm the carotenoid composition of jackfruit by high-performance liquid chromatography connected to photodiode array and mass spectrometry detectors (HPLC-PDA-MS/MS). The main carotenoids were all-trans-lutein (24-44%), all-trans-beta-carotene (24-30%), all-trans-neoxanthin (4-19%), 9-cis-neoxanthin (4-9%) and 9-cis-violaxanthin (4-10%). Either qualitative or quantitative differences, mainly related to the lutein proportion, were found among three batches of jackfruit. Since the fruits from batch A showed significantly lower contents for almost all carotenoids, it also had the lowest total carotenoid content (34.1 microg/100 g) and provitamin A value, whereas the total carotenoid ranged from 129.0 to 150.3 microg/100 g in the other batches. The provitamin A values from batches B and C were 3.3 and 4.3 microg RAE/100 g, respectively. The carotenoid composition of jackfruit was successfully determined, where 14 of the 18 identified carotenoids were reported for first time. Differences among batches may be due to genetic and/or agricultural factors.

  12. HPLC-MS/MS investigation of biochemical markers for the disclosure of erythropoietin abuse in sports

    Science.gov (United States)

    Appolonova, S. A.; Dikunets, M. A.; Rodchenkov, G. M.

    2009-04-01

    The polypeptide hormone erythropoietin (EPO), which is a forbidden doping drug, was determined by high-performance liquid chromatography combined with tandem mass spectrometry (HPLC-MS/MS). The hypothesis about the influence of EPO on the asymmetric dimethylarginine (ADMA)-dimethylargininedime-thylaminohydrolase (DDAH)-NO-synthase system was verified. Changes in this system can serve as indirect biochemical markers of the presence of the forbidden EPO drug in the organism. In the test group, the concentrations of biochemical markers varied from 10 to 40 μg/ml for ADMA and symmetrical DMA (SDMA) and from 0.5 to 10 μg/ml for arginine and citrulline. A single intravenous administration of r-HuEPO (Epocrin, 2000 ME/day) for two volunteers reliably increased ADMA, SDMA, arginine, and citrulline concentrations to 40-270 μg/ml, 40-240μg/ml, 10-60 μg/ml, and 12-140 μg/ml, respectively, with respect to the reference values. The simultaneous increase in arginine, methylarginines, and citrulline contents could be an indirect marker of EPO abuse. The method is recommended for fast screening analysis.

  13. Identification of proteins from tuberculin purified protein derivative (PPD) by LC-MS/MS.

    Science.gov (United States)

    Borsuk, Sibele; Newcombe, Jane; Mendum, Tom A; Dellagostin, Odir A; McFadden, Johnjoe

    2009-11-01

    The tuberculin purified protein derivative (PPD) is a widely used diagnostic antigen for tuberculosis, however it is poorly defined. Most mycobacterial proteins are extensively denatured by the procedure employed in its preparation, which explains previous difficulties in identifying constituents from PPD to characterize their behaviour in B- and T-cell reactions. We here described a proteomics-based characterization of PPD from several different sources by LC-MS/MS, which combines the solute separation power of HPLC, with the detection power of a mass spectrometer. The technique is able to identify proteins from complex mixtures of peptide fragments. A total of 171 different proteins were identified among the four PPD samples (two bovine PPD and two avium PPD) from Brazil and UK. The majority of the proteins were cytoplasmic (77.9%) and involved in intermediary metabolism and respiration (24.25%) but there was a preponderance of proteins involved in lipid metabolism. We identified a group of 21 proteins that are present in both bovine PPD but were not detected in avium PPD preparation. In addition, four proteins found in bovine PPD are absent in Mycobacterium bovis BCG vaccine strain. This study provides a better understanding of the tuberculin PPD components leading to the identification of additional antigens useful as reagents for specific diagnosis of tuberculosis.

  14. Multi-mycotoxin stable isotope dilution LC-MS/MS method for Fusarium toxins in beer.

    Science.gov (United States)

    Habler, Katharina; Gotthardt, Marina; Schüler, Jan; Rychlik, Michael

    2017-03-01

    A stable isotope dilution LC-MS/MS multi-mycotoxin method was developed for 12 different Fusarium toxins including modified mycotoxins in beer (deoxynivalenol-3-glucoside, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyl-deoxynivalenol, HT2-toxin, T2-toxin, enniatin B, B1, A1, A, beauvericin and zearalenone). As sample preparation and purification of beer a combined solid phase extraction for trichothecenes, enniatins, beauvericin and zearalenone was firstly developed. The validation of the new method gave satisfying results: intra-day and inter-day precision and recoveries were 1-5%, 2-8% and 72-117%, respectively. In total, 61 different organic and conventional beer samples from Germany and all over the world were analyzed by using the newly developed multi-mycotoxin method. In summary, deoxynivalenol, deoxynivalenol-3-glucoside, 3-acetyldeoxynivaleneol and enniatin B were quantified in rather low contents in the investigated beer samples. None of the other monitored Fusarium toxins like 15-acetyldeoxynivalenol, HT2- and T2-toxin, zearalenone, enniatin B1, A1, A or beauvericin were detectable. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. MASPECTRAS: a platform for management and analysis of proteomics LC-MS/MS data

    Directory of Open Access Journals (Sweden)

    Rader Robert

    2007-06-01

    Full Text Available Abstract Background The advancements of proteomics technologies have led to a rapid increase in the number, size and rate at which datasets are generated. Managing and extracting valuable information from such datasets requires the use of data management platforms and computational approaches. Results We have developed the MAss SPECTRometry Analysis System (MASPECTRAS, a platform for management and analysis of proteomics LC-MS/MS data. MASPECTRAS is based on the Proteome Experimental Data Repository (PEDRo relational database schema and follows the guidelines of the Proteomics Standards Initiative (PSI. Analysis modules include: 1 import and parsing of the results from the search engines SEQUEST, Mascot, Spectrum Mill, X! Tandem, and OMSSA; 2 peptide validation, 3 clustering of proteins based on Markov Clustering and multiple alignments; and 4 quantification using the Automated Statistical Analysis of Protein Abundance Ratios algorithm (ASAPRatio. The system provides customizable data retrieval and visualization tools, as well as export to PRoteomics IDEntifications public repository (PRIDE. MASPECTRAS is freely available at http://genome.tugraz.at/maspectras Conclusion Given the unique features and the flexibility due to the use of standard software technology, our platform represents significant advance and could be of great interest to the proteomics community.

  16. Multifamily determination of pesticide residues in soya-based nutraceutical products by GC/MS-MS.

    Science.gov (United States)

    Páleníková, Agneša; Martínez-Domínguez, Gerardo; Arrebola, Francisco Javier; Romero-González, Roberto; Hrouzková, Svetlana; Frenich, Antonia Garrido

    2015-04-15

    An analytical method based on a modified QuEChERS extraction coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) was evaluated for the determination of 177 pesticides in soya-based nutraceutical products. The QuEChERS method was optimised and different extraction solvents and clean-up approaches were tested, obtaining the most efficient conditions with a mixture of sorbents (PSA, C18, GBC and Zr-Sep(+)). Recoveries were evaluated at 10, 50 and 100 μg/kg and ranged between 70% and 120%. Precision was expressed as relative standard deviation (RSD), and it was evaluated for more than 160 pesticides as intra and inter-day precision, with values always below 20% and 25%, respectively. Limits of detection (LODs) ranged from 0.1 to 10 μg/kg, whereas limits of quantification (LOQs) from 0.5 to 20 μg/kg. The applicability of the method was proved by analysing soya-based nutraceuticals. Two pesticides were found in these samples, malathion and pyriproxyfen, at 11.1 and 1.5 μg/kg respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. LC-MS/MS analysis of neonicotinoid insecticides: Residue findings in chilean honeys

    Directory of Open Access Journals (Sweden)

    Raquel Bridi

    Full Text Available ABSTRACT Neonicotinoids are a relatively new generation of insecticides that have been used for control of pests such as aphids, leafhoppers and whiteflies. This paper presents for the first time a determination of residues of four neonicotinoid insecticides (acetamiprid, thiamethoxam, thiacloprid and imidacloprid in Chilean honey using QuEChERS extraction and UHPLC-MS/MS analysis. The limits of detection and quantification found for all analytes ranging from 0.34 to 1.43 μg kg-1 and from 0.30 to 4.76 μg kg-1, respectively. The extraction using QuEChERS method provided recoveries over 79% and the precision showed coefficient of variation lower than 20%. These data are in agreement with the international criteria that recommend general recovery limits of 70 - 120%. Of the 16 samples analyzed, in three honey samples neonicotinoids pesticides were detected. These three samples were collected from the same geographical area (Rengo. Fruit and grain production characterize the province of Rengo. The analysis of the botanical origin of these honeys showed the absence of pollen grains of crops and the majority presence of pollen grains of weeds such as Medicago sativa, Galega officinalis and Brassica rapa, which could be associated with crops. Although the residue levels found were low, the results also confirm the actual occurrence of a transfer of neonicotinoid insecticides from exposed honeybees into honey.

  18. LC-MS/MS Estimation of Propranolol level in Exhaled Breath Condensate

    Directory of Open Access Journals (Sweden)

    Samin Hamidi 1, Maryam Amini 2, Maryam Khoubnasabjafari 3, Vahid Jouyban-Gharamaleki 4,5, Hossein Sate 6, Abolghasem Jouyban 5,7 *

    2017-12-01

    Full Text Available Background: Exhaled breath condensate (EBC could be used as a non-invasive and alternative specimen to urine and blood for monitoring propranolol levels. A simple, sensitive and selective liquid chromatography–tandem mass spectrometry (LC–MS/MS method is employed for the determination of propranolol in EBC samples. Methods: Samples directly injected to a C18 analytical column and isocratically separated using a mobile phase composed of methanol + acetic acid (99:1 v/v. Detection was performed by positive electrospray ionization in multiple reaction monitoring and selected ion recording modes. Results: The chromatographic separation was obtained within 6.0 min and was linear over the concentration range of 5.6–224.0 ng/mL (R2 = 0.999. The accuracy and precision of the method were within 15% according to FDA guideline. The found concentrations of propranolol in EBC of two patients receiving 80 mg/day were 30 and 40 ng/mL. Conclusion: Developed method was applied to determine propranolol levels in three patients receiving propranolol in their medication. The obtained propranolol levels in EBC could be used to develop simpler, cheaper and more feasible analytical methods to be used in routine analysis of propranolol in biomedical analytical laboratories.

  19. Simultaneous determination of metformin and vildagliptin in human plasma by a HILIC-MS/MS method.

    Science.gov (United States)

    Pontarolo, Roberto; Gimenez, Ana Carolina; de Francisco, Thais Martins Guimarães; Ribeiro, Rômulo Pereira; Pontes, Flávia Lada Degaut; Gasparetto, João Cleverson

    2014-08-15

    The objective of this work was to develop and validate a HILIC-MS/MS method for the simultaneous determination of metformin and vildagliptin in human plasma. Chromatographic separation was achieved using an Atlantis HILIC Silica 150-mm × 2.1-mm, 3-μm particle size column maintained at 40°C. The isocratic mobile phase consisted of 20% water and 80% acetonitrile/water solution 95:5 (v/v), containing both 0.1% formic acid and 3mM ammonium formate. The flow rate was maintained at 400 μL min(-1). Data from validation studies demonstrated that the new method is highly selective, sensitive (limits of detection vildagliptin in plasma volunteers who orally received a single dose of metformin (850 mg), vildagliptin (50mg) or drug association (metformin 850 mg+vildagliptin 50mg). The new method can thus also be used as a tool for the clinical monitoring of metformin and vildagliptin. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Simultaneous quantification of seven hippocampal neurotransmitters in depression mice by LC-MS/MS.

    Science.gov (United States)

    Huang, Fei; Li, Jia; Shi, Hai-Lian; Wang, Ting-ting; Muhtar, Wahaf; Du, Min; Zhang, Bei-bei; Wu, Hui; Yang, Li; Hu, Zhi-bi; Wu, Xiao-jun

    2014-05-30

    There is no method available to simultaneously detect GABA, Glu, Epi, NE, DA, 5-HT and 5-HIAA in mouse hippocampus. A rapid and sensitive LC-MS/MS method has been developed for simultaneously measuring seven neurotransmitters in mouse hippocampus. The analytes were detected in positive mode with multiple reaction monitoring (MRM) and the procedure was completed in less than 9min. This method exhibited excellent linearity for all of the analytes with regression coefficients higher than 0.99, and showed good intra- and inter-day precisions (RSDneurotransmitters in a mouse depression model induced by successive methylprednisolone injections. The results indicated that this depression model was closely associated with the decreased level of Epi (p=0.002) and elevated ratio of 5-HIAA/5-HT (p=0.01), which has never been reported elsewhere. Compared with previous methods, current approach is more convenient without any pre-column derivatization of the analytes but enhances detectability with incremental neurotransmitter profile and shortens detection time. This work represents the first accurate simultaneous determination of seven neurotransmitters in the mouse depression model induced by methylprednisolone. The reliable method will benefit the research of neurological diseases with the altered neurotransmitter profile in brain. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Antioxidant properties and phenolic profile characterization by LC-MS/MS of selected Tunisian pomegranate peels.

    Science.gov (United States)

    Abid, Mouna; Yaich, Héla; Cheikhrouhou, Salma; Khemakhem, Ibtihel; Bouaziz, Mohamed; Attia, Hamadi; Ayadi, M A

    2017-08-01

    Antioxidant contents and activities of different extracts from four Tunisian pomegranate peels, locally called "Acide", "Gabsi", "Nebli" and "Tounsi", were studied. Peels samples were extracted with three solvents (water, ethanol and acetone). For each extract, the total phenol contents and antioxidant activity were evaluated. The highest values of polyphenol, tannins, flavonoids and anthocyanins were recorded in the acetone extract of Acide ecotype with 304.6 mg gallic acid equivalent/g; 292.23 mg gallic acid equivalent/g; 15.46 mg Quercetin/g and 54.51 mg cy-3-glu/100 g, respectively. The acetone extract of Acide ecotype also showed the highest free radical-scavenging and reducing power activity compared to other extracts. Besides, the phytochemical analysis by LC-MS/MS revealed a high content of ellagitannins with punicalagin and punicalagin derivatives as the major compounds that might be responsible for promising antioxidant activity of pomegranate peel extracts. Two compounds (Castalagin derivative and Galloyl-bis-HHDP-hex derivative) were detected only in "Acide" ecotype in important contents.

  2. Quantitative Determination of Ivermectin in Raw Milk Using Positive ESI LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Meenakshi Dahiya

    2010-01-01

    Full Text Available Ivermectin, a veterinary drug, is commonly used endectocide for animal husbandry. The drug is available in the form of subcutaneous or topical formulations. Its application may cause accumulation of its residues into the animal tissues, which ultimately find their way into the food products, such as milk and meat products. In order to determine the residues of ivermectin in milk, a comparatively simple, sensitive and rapid method was developed and validated using LC-MS/MS. The MRM transitions corresponding to m/z 892.71>569.6, 892.71>551.5 and 892.71>307.3 were used for the purpose of quantification and evaluation of other parameters of the method. The limit of detection of the method was found to be 0.1 μg/kg and the limit of quantitation was calculated as 0.2 μg/kg. The method was found to be linear in the range of 1.0 ng/mL to 100.0 ng/mL with correlation coefficient of 0.9992 for pure calibration curve and 0.9990 for the matrix- matched calibration curve. The recoveries of ivermectin from the spiked samples of raw milk were found between 85 to 105%.

  3. Secondary Metabolite Profiling of Species of the Genus Usnea by UHPLC-ESI-OT-MS-MS

    Directory of Open Access Journals (Sweden)

    Francisco Salgado

    2017-12-01

    Full Text Available Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria, which are considered among the slowest growing organisms, with strong tolerance to adverse environmental conditions. There are about 400 genera and 1600 species of lichens and those belonging to the Usnea genus comprise about 360 of these species. Usnea lichens have been used since ancient times as dyes, cosmetics, preservatives, deodorants and folk medicines. The phytochemistry of the Usnea genus includes more than 60 compounds which belong to the following classes: depsides, depsidones, depsones, lactones, quinones, phenolics, polysaccharides, fatty acids and dibenzofurans. Due to scarce knowledge of metabolomic profiles of Usnea species (U. barbata, U. antarctica, U. rubicunda and U. subfloridana, a study based on UHPLC-ESI-OT-MS-MS was performed for a comprehensive characterization of their secondary metabolites. From the methanolic extracts of these species a total of 73 metabolites were identified for the first time using this hyphenated technique, including 34 compounds in U. barbata, 21 in U. antarctica, 38 in U. rubicunda and 37 in U. subfloridana. Besides, a total of 13 metabolites were not identified and reported so far, and could be new according to our data analysis. This study showed that this hyphenated technique is rapid, effective and accurate for phytochemical identification of lichen metabolites and the data collected could be useful for chemotaxonomic studies.

  4. Substitution pattern elucidation of hydroxypropyl Pinus pinaster (Ait.) bark polyflavonoid derivatives by ESI(-)-MS/MS.

    Science.gov (United States)

    García Marrero, Danny E; Glasser, Wolfgang G; Pizzi, Antonio; Paczkowski, Sebastian; Laborie, Marie-Pierre G

    2014-10-01

    The structure of condensed tannins (CTs) from Pinus pinaster bark extract and their hydroxypropylated derivatives with four degrees of substitution (DS 1, 2, 3 and 4) has been characterized for the first time using negative-ion mode electrospray ionization tandem mass spectrometry (ESI(-)-MS/MS). The results showed that P. pinaster bark CTs possess structural homogeneity in terms of monomeric units (C(15), catechin). The oligomer sizes were detected to be dimers to heptamers. The derivatives showed typical phenyl-propyl ether mass fragmentation by substituent elimination (58 amu) and inherent C(15) flavonoid fissions. The relative abundance of the product ions revealed a preferential triple, tetra-/penta- and octa- hydroxypropylation substitution pattern in the monomer, dimer and trimer derivatives, respectively. A defined order of -OH reactivity towards propylene oxide was established by means of multistage experiments (A-ring ≥ B-ring > C-ring). A high structural heterogeneity of the modified oligomers was detected. Copyright © 2014 John Wiley & Sons, Ltd.

  5. Determination of piroxicam from rat articular tissue and plasma based on LC-MS/MS.

    Science.gov (United States)

    Kim, Han Sol; Cho, Ha Ra; Ho, Myoung Jin; Kang, Myung Joo; Choi, Yong Seok

    2016-12-01

    Osteoarthritis (OA) is the most common type of arthritis. To manage OA, in general, oral administration of non-steroidal anti-inflammatory drugs (NSAIDs) is used. Recently, the analgesic and anti-inflammatory efficacy of piroxicam (PX), a long-acting NSAID, by intra-articular (IA) administration in OA was reported, and the possibility that PX is distributed in articular tissues at a certain concentration was raised. Thus, herein, novel LC-MS/MS methods to detect PX in rat articular tissue and plasma are presented. For articular tissue, solvent extraction with acetonitrile for 12 h was employed and a protein precipitation method was used for the preparation of a plasma sample. The developed methods were validated by following the FDA guidelines, and the validated methods were successfully applied to a PK study of IA PX. The present study presents, to our knowledge, the first method of determining a drug in articular tissue. Additionally, the level of PX in articular tissue after IA PX administration was experimentally confirmed for the first time using the present methods. Therefore, the present methods provide a new direction for in vivo evaluation for IA PX formulations and contribute to the development of alternative IA PX formulations with better effects for the treatment of OA.

  6. Antioxidant capacity and phenolic compounds of Lonicerae macranthoides by HPLC-DAD-QTOF-MS/MS.

    Science.gov (United States)

    Hu, Xin; Chen, Lin; Shi, Shuyun; Cai, Ping; Liang, Xuejuan; Zhang, Shuihan

    2016-05-30

    Lonicerae macranthoides with strong antioxidant activity is commonly used in traditional Chinese medicine and folk tea/beverage. However, detailed information about its antioxidant activity and bioactive compounds is limited. Then at first, we comparatively evaluated total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activities of water extract, petroleum ether, ethyl acetate and n-butanol fractions of L. macranthoides. Ethyl acetate fraction exhibited the highest level of TPC (207.38 mg GAE/g DW), TFC (53.06 mg RE/g DW) and the best DPPH scavenge activity and reducing power. n-Butanol fraction showed the best ABTS(+) and O2(-) scavenging activities. Interestingly, water extract, ethyl acetate and n-butanol fractions showed stronger antioxidant activities than positive control, butylated hydroxytoluene (BHT). After that, thirty-one antioxidant phenolic compounds, including twenty-two phenolic acids and nine flavonoids, were screened by DPPH-HPLC experiment and then identified using HPLC-DAD-QTOF-MS/MS. It is noted that twenty-one compounds (1, 3-4, 6-17, 19, 23, 26, 28-29, and 31), as far as was known, were discovered from L. macranthoide for the first time, and eleven of them (3-4, 10-17, and 23) were reported in Lonicera species for the first time. Results indicated that L. macranthoides could serve as promising source of rich antioxidants in foods, beverages and medicines for health promotion. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Simultaneous determination of telmisartan and amlodipine in dog plasma by LC-MS-MS.

    Science.gov (United States)

    Wang, Baolian; Sheng, Li; Li, Yan

    2015-01-01

    A simple, rapid and sensitive method was established for the simultaneous determination of telmisartan and amlodipine in dog plasma by a HPLC-MS-MS analysis. The plasma sample preparation was a simple deproteinization by the addition of three volumes of methanol/acetonitrile mixture followed by centrifugation. The analytes and internal standard diphenhydramine were separated on a Zorbax SB-C18 column with a mobile phase of acetonitrile : water (45 : 55, v/v) at a flow rate of 0.2 mL/min with an operating temperature of 25°C. Detection was carried out by electrospray ionization in positive-ion multiple reaction monitoring mode. The calibration plots in dog plasma were linear over the ranges of 0.5-2,000 ng/mL for telmisartan and 0.5-500 ng/mL for amlodipine. The lower limit of quantification was 0.5 ng/mL for two analytes. The intra- and interday precisions (RSD%) were within 9.0%. The average recoveries of analytes were >85.0%. The method was successfully applied to the pharmacokinetic study of the two compounds after oral administration of telmisartan-amlodipine combination preparation to dogs. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. IPeak: An open source tool to combine results from multiple MS/MS search engines.

    Science.gov (United States)

    Wen, Bo; Du, Chaoqin; Li, Guilin; Ghali, Fawaz; Jones, Andrew R; Käll, Lukas; Xu, Shaohang; Zhou, Ruo; Ren, Zhe; Feng, Qiang; Xu, Xun; Wang, Jun

    2015-09-01

    Liquid chromatography coupled tandem mass spectrometry (LC-MS/MS) is an important technique for detecting peptides in proteomics studies. Here, we present an open source software tool, termed IPeak, a peptide identification pipeline that is designed to combine the Percolator post-processing algorithm and multi-search strategy to enhance the sensitivity of peptide identifications without compromising accuracy. IPeak provides a graphical user interface (GUI) as well as a command-line interface, which is implemented in JAVA and can work on all three major operating system platforms: Windows, Linux/Unix and OS X. IPeak has been designed to work with the mzIdentML standard from the Proteomics Standards Initiative (PSI) as an input and output, and also been fully integrated into the associated mzidLibrary project, providing access to the overall pipeline, as well as modules for calling Percolator on individual search engine result files. The integration thus enables IPeak (and Percolator) to be used in conjunction with any software packages implementing the mzIdentML data standard. IPeak is freely available and can be downloaded under an Apache 2.0 license at https://code.google.com/p/mzidentml-lib/. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Multimycotoxin LC-MS/MS Analysis in Tea Beverages after Dispersive Liquid-Liquid Microextraction (DLLME).

    Science.gov (United States)

    Pallarés, Noelia; Font, Guillermina; Mañes, Jordi; Ferrer, Emilia

    2017-11-29

    The aim of the present study was to develop a multimycotoxin liquid chromatography tandem mass spectrometry (LC-MS/MS) method with a dispersive liquid-liquid microextraction procedure (DLLME) for the analysis of AFs, 3aDON, 15aDON, NIV, HT-2, T-2, ZEA, OTA, ENNs, and BEA in tea beverages and to evaluate their mycotoxin contents. The proposed method was characterized in terms of linearity, limits of detection (LODs), limits of quantification (LOQs), recoveries, repeatability (intraday precision), reproducibility (interday precision), and matrix effects to check suitability. The results show LODs in the range of 0.05-10 μg/L, LOQs in the range of 0.2-33 μg/L, and recoveries in the range of 65-127% (RSD tea, red tea, green tea, and green mint tea. The results show that, of the analyzed mycotoxins, AFB2, AFG2, 15aDON, AFG1, and ENB were detected in the samples. AFB2 (14.4-32.2 μg/L) and 15aDON (60.5-61 μg/L) presented the highest levels. Green mint tea contained the highest concentration of mycotoxins. The risk assessment study shows that the population is not much exposed to mycotoxins through the consumption of tea beverages.

  10. The potential use of complex derivatization procedures in comprehensive HPLC-MS/MS detection of anabolic steroids.

    Science.gov (United States)

    Baranov, Pavel A; Appolonova, Svetlana A; Rodchenkov, Grigory M

    2010-10-01

    The use of two separate derivatization procedures with the formation of oxime (hydroxyl ammonium pretreatment) and picolinoyl (mixed anhydride method) derivates of anabolic steroids following HPLC-MS/MS analysis was proposed. The main product ions of obtained derivatives for 21 anabolic steroids were evaluated and fragmentation pathways were compared.The analysis of MS/MS spectra for underivatized steroids versus oxime or picolinoyl derivatives showed that in case of analytes containing conjugated double bonds in sterane core all of the observed MS/MS spectra contained abundant product ions of diagnostic value. The implementation of derivatization procedures to such compounds is useful for upgrading sensitivity or selectivity of the evaluated method. On the other hand, MS/MS spectra of underivatized and oxime analytes without conjugated double bonds in sterane core produce spectra with large amounts of low abundant product ions. Picolinoyl derivatives formation leads to highly specific spectra with product ions of diagnostic value coupled with sensitive and selective analysis at the same time. The intra- and inter-group comparison analysis revealed that fragmentation pathways for underivatized steroids and correspondent oxime derivatives are similar.The obtained oxime and picolinoyl derivatives provided 10-15 times higher ESI response in the HPLC-ESI-MS-selected reaction monitoring (SRM) when compared to those of underivatized molecules in positive HPLC-ESI-MS mode.Due to the laborious sample preparation we suggest to use the performed strategy for confirmation analysis purposes, metabolic studies or while the identification of new steroids or steroid-like substances. Copyright © 2010 John Wiley & Sons, Ltd.

  11. Improvement of the M/S manipulator maintenance at OSL

    International Nuclear Information System (INIS)

    Kuwana, Koichi; Ouchi, Hiroshi; Ito, Yutaka; Sato, Yoshihiro; Midorikawa, Mituhiro; Hayakawa, Tuyoshi

    2010-01-01

    The safeguards inspection samples from the JNFL Rokkasho Reprocessing Plant (RRP) are received and analyzed at the On Site Laboratory (OSL). Since the samples from the input accountancy tank of the RRP contain a lot of fission products, they are treated in a hot-cell line with a M/S (Master /Slave) manipulator. Special equipment and tools were used for the maintenance of the M/S manipulator, especially for the exchange of the M/S manipulator. However, the manipulator exchange work was not easy due to the limitation of the space in the OSL. For solution to this problem, a monorail and monorail hoist equipment was installed onto wall surface of analytical room close to each M/S manipulator, and then it made the exchange of M/S manipulator easy without special equipment and tools. Additionally, operator was freed from the burden of working space arranging for the exchange of M/S manipulator such as removing of analytical equipments. This report represents the improvement of operation for the exchange of M/S manipulator with installation of monorail and hoist equipment. (author)

  12. LA-ICP-MS of magnetite: Methods and reference materials

    Science.gov (United States)

    Nadoll, P.; Koenig, A.E.

    2011-01-01

    Magnetite (Fe3O4) is a common accessory mineral in many geologic settings. Its variable geochemistry makes it a powerful petrogenetic indicator. Electron microprobe (EMPA) analyses are commonly used to examine major and minor element contents in magnetite. Laser ablation ICP-MS (LA-ICP-MS) is applicable to trace element analyses of magnetite but has not been widely employed to examine compositional variations. We tested the applicability of the NIST SRM 610, the USGS GSE-1G, and the NIST SRM 2782 reference materials (RMs) as external standards and developed a reliable method for LA-ICP-MS analysis of magnetite. LA-ICP-MS analyses were carried out on well characterized magnetite samples with a 193 nm, Excimer, ArF LA system. Although matrix-matched RMs are sometimes important for calibration and normalization of LA-ICP-MS data, we demonstrate that glass RMs can produce accurate results for LA-ICP-MS analyses of magnetite. Cross-comparison between the NIST SRM 610 and USGS GSE-1G indicates good agreement for magnetite minor and trace element data calibrated with either of these RMs. Many elements show a sufficiently good match between the LA-ICP-MS and the EMPA data; for example, Ti and V show a close to linear relationship with correlation coefficients, R2 of 0.79 and 0.85 respectively. ?? 2011 The Royal Society of Chemistry.

  13. Quantification of acetaminophen (paracetamol) in human plasma and urine by stable isotope-dilution GC-MS and GC-MS/MS as pentafluorobenzyl ether derivative.

    Science.gov (United States)

    Trettin, Arne; Zoerner, Alexander A; Böhmer, Anke; Gutzki, Frank-Mathias; Stichtenoth, Dirk O; Jordan, Jens; Tsikas, Dimitrios

    2011-08-01

    We report on the quantitative determination of acetaminophen (paracetamol; NAPAP-d(0)) in human plasma and urine by GC-MS and GC-MS/MS in the electron-capture negative-ion chemical ionization (ECNICI) mode after derivatization with pentafluorobenzyl (PFB) bromide (PFB-Br). Commercially available tetradeuterated acetaminophen (NAPAP-d(4)) was used as the internal standard. NAPAP-d(0) and NAPAP-d(4) were extracted from 100-μL aliquots of plasma and urine with 300 μL ethyl acetate (EA) by vortexing (60s). After centrifugation the EA phase was collected, the solvent was removed under a stream of nitrogen gas, and the residue was reconstituted in acetonitrile (MeCN, 100 μL). PFB-Br (10 μL, 30 vol% in MeCN) and N,N-diisopropylethylamine (10 μL) were added and the mixture was incubated for 60 min at 30 °C. Then, solvents and reagents were removed under nitrogen and the residue was taken up with 1000 μL of toluene, from which 1-μL aliquots were injected in the splitless mode. GC-MS quantification was performed by selected-ion monitoring ions due to [M-PFB](-) and [M-PFB-H](-), m/z 150 and m/z 149 for NAPAP-d(0) and m/z 154 and m/z 153 for NAPAP-d(4), respectively. GC-MS/MS quantification was performed by selected-reaction monitoring the transition m/z 150 → m/z 107 and m/z 149 → m/z 134 for NAPAP-d(0) and m/z 154 → m/z 111 and m/z 153 → m/z 138 for NAPAP-d(4). The method was validated for human plasma (range, 0-130 μM NAPAP-d(0)) and urine (range, 0-1300 μM NAPAP-d(0)). Accuracy (recovery, %) ranged between 89 and 119%, and imprecision (RSD, %) was below 19% in these matrices and ranges. A close correlation (r>0.999) was found between the concentrations measured by GC-MS and GC-MS/MS. By this method, acetaminophen can be reliably quantified in small plasma and urine sample volumes (e.g., 10 μL). The analytical performance of the method makes it especially useful in pediatrics. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Methods in endogenous steroid profiling - A comparison of gas chromatography mass spectrometry (GC-MS) with supercritical fluid chromatography tandem mass spectrometry (SFC-MS/MS).

    Science.gov (United States)

    Teubel, Juliane; Wüst, Bernhard; Schipke, Carola G; Peters, Oliver; Parr, Maria Kristina

    2018-06-15

    In various fields of endocrinology, the determination of steroid hormones synthesised by the human body plays an important role. Research on central neurosteroids has been intensified within the last years, as they are discussed as biomarkers for various cognitive disorders. Their concentrations in cerebrospinal fluid (CSF) are considered to be regulated independently from peripheral fluids. For that reason, the challenging matrix CSF becomes a very interesting specimen for analysis. Concentrations are expected to be very low and available amount of CSF is limited. Thus, a comprehensive method for very sensitive quantification of a set of analytes as large as possible in one analytical aliquot is desired. However, high structural similarities of the selected panel of 51 steroids and steroid sulfates, including numerous isomers, challenges achievement of chromatographic selectivity. Since decades the analysis of endogenous steroids in various body fluids is mainly performed by gas chromatography (GC) coupled to (tandem) mass spectrometry (MS(/MS)). Due to the structure of the steroids of interest, derivatisation is performed to meet the analytical requirements for GC-MS(/MS). Most of the laboratories use a two-step derivatisation in multi-analyte assays that was already published in the 1980s. However, for some steroids this elaborate procedure yields multiple isomeric derivatives. Thus, some laboratories utilize (ultra) high performance liquid chromatography ((U)HPLC)-MS/MS as alternative but, even UHPLC is not able to separate some of the isomeric pairs. Supercritical fluid chromatography (SFC) as an orthogonal separation technique to GC and (U)HPLC may help to overcome these issues. Within this project the two most promising methods for endogenous steroid profiling were investigated and compared: the "gold standard" GC-MS and the orthogonal separation technique SFC-MS/MS. Different derivatisation procedures for gas chromatographic detection were explored and the

  15. Precise and accurate isotope ratio measurements by ICP-MS.

    Science.gov (United States)

    Becker, J S; Dietze, H J

    2000-09-01

    The precise and accurate determination of isotope ratios by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) is important for quite different application fields (e.g. for isotope ratio measurements of stable isotopes in nature, especially for the investigation of isotope variation in nature or age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, quality assurance of fuel material, for reprocessing plants, nuclear material accounting and radioactive waste control, for tracer experiments using stable isotopes or long-lived radionuclides in biological or medical studies). Thermal ionization mass spectrometry (TIMS), which used to be the dominant analytical technique for precise isotope ratio measurements, is being increasingly replaced for isotope ratio measurements by ICP-MS due to its excellent sensitivity, precision and good accuracy. Instrumental progress in ICP-MS was achieved by the introduction of the collision cell interface in order to dissociate many disturbing argon-based molecular ions, thermalize the ions and neutralize the disturbing argon ions of plasma gas (Ar+). The application of the collision cell in ICP-QMS results in a higher ion transmission, improved sensitivity and better precision of isotope ratio measurements compared to quadrupole ICP-MS without the collision cell [e.g., for 235U/238U approximately 1 (10 microg x L(-1) uranium) 0.07% relative standard deviation (RSD) vs. 0.2% RSD in short-term measurements (n = 5)]. A significant instrumental improvement for ICP-MS is the multicollector device (MC-ICP-MS) in order to obtain a better precision of isotope ratio measurements (with a precision of up to 0.002%, RSD). CE- and HPLC-ICP-MS are used for the separation of isobaric interferences of long-lived radionuclides and stable isotopes by determination of spallation nuclide abundances in an irradiated tantalum target.

  16. Analytical methods for multiresidue determination of sulfonamides and trimethoprim in meat and ground water samples by CE-MS and CE-MS/MS.

    Science.gov (United States)

    Soto-Chinchilla, Jorge J; García-Campaña, Ana M; Gámiz-Gracia, Laura

    2007-11-01

    This paper presents two methods based on CZE-MS detection and CZE-MS/MS detection developed for the multiresidue determination of ten sulfonamides (sulfapyridine, sulfadoxin, sulfamethazine, sulfadimethoxine, sulfameter, sulfamerazine, sulfachlorpyridazine, sulfadiazine, sulfamethoxazole, and sulfamethizole) and a potentiator, trimethoprim (TMP), whose contents are regulated by the EU Council Regulation no. 2377/90 in animal edible tissues. Experimental designs were employed to optimize the electrospray conditions. MS/MS experiments using an IT as analyzer operating in multiple reaction monitoring (MRM) mode were carried out to achieve the minimum number of points according to the 2002/657/EC European Decision for unambiguous identification. The proposed procedures have been compared in terms of the performance characteristics and trueness. The limits of detection and quantification were in all cases lower than the maximum residue limits legislated for these compounds and the recoveries were satisfactory, being possible the application for their monitoring in foodstuff of animal origin and in environmental samples, allowing the determination of sulfonamides and TMP residues in meat and in superficial water in the low microg/L range.

  17. Importance of MS selectivity and chromatographic separation in LC-MS/MS-based methods when investigating pharmaceutical metabolites in water. Dipyrone as a case of study.

    Science.gov (United States)

    Ibáñez, M; Gracia-Lor, E; Sancho, J V; Hernández, F

    2012-08-01

    Pharmaceuticals are emerging contaminants of increasing concern because of their presence in the aquatic environment and potential to reach drinking-water sources. After human and/or veterinary consumption, pharmaceuticals can be excreted in unchanged form, as the parent compound, and/or as free or conjugated metabolites. Determination of most pharmaceuticals and metabolites in the environment is commonly made by liquid chromatography (LC) coupled to mass spectrometry (MS). LC coupled to tandem MS is the technique of choice nowadays in this field. The acquisition of two selected reaction monitoring (SRM) transitions together with the retention time is the most widely accepted criterion for a safe quantification and confirmation assay. However, scarce attention is normally paid to the selectivity of the selected transitions as well as to the chromatographic separation. In this work, the importance of full spectrum acquisition high-resolution MS data using a hybrid quadrupole time-of-flight analyser and/or a suitable chromatographic separation (to reduce the possibility of co-eluting interferences) is highlighted when investigating pharmaceutical metabolites that share common fragment ions. For this purpose, the analytical challenge associated to the determination of metabolites of the widely used analgesic dipyrone (also known as metamizol) in urban wastewater is discussed. Examples are given on the possibilities of reporting false positives of dypirone metabolites by LC-MS/MS under SRM mode due to a wrong assignment of identity of the compounds detected. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Distinctive and Complementary MS2 Fragmentation Characteristics for Identification of Sulfated Sialylated N-Glycopeptides by nanoLC-MS/MS Workflow

    Science.gov (United States)

    Kuo, Chu-Wei; Guu, Shih-Yun; Khoo, Kay-Hooi

    2018-04-01

    High sensitivity identification of sulfated glycans carried on specific sites of glycoproteins is an important requisite for investigation of molecular recognition events involved in diverse biological processes. However, aiming for resolving site-specific glycosylation of sulfated glycopeptides by direct LC-MS2 sequencing is technically most challenging. Other than the usual limiting factors such as lower abundance and ionization efficiency compared to analysis of non-glycosylated peptides, confident identification of sulfated glycopeptides among the more abundant non-sulfated glycopeptides requires additional considerations in the selective enrichment and detection strategies. Metal oxide has been applied to enrich phosphopeptides and sialylated glycopeptides, but its use to capture sulfated glycopeptides has not been investigated. Likewise, various complementary MS2 fragmentation modes have yet to be tested against sialylated and non-sialylated sulfoglycopeptides due to limited appropriate sample availability. In this study, we have investigated the feasibility of sequencing tryptic sulfated N-glycopeptide and its MS2 fragmentation characteristics by first optimizing the enrichment methods to allow efficient LC-MS detection and MS2 analysis by a combination of CID, HCD, ETD, and EThcD on hybrid and tribrid Orbitrap instruments. Characteristic sulfated glyco-oxonium ions and direct loss of sulfite from precursors were detected as evidences of sulfate modification. It is anticipated that the technical advances demonstrated in this study would allow a feasible extension of our sulfoglycomic analysis to sulfoglycoproteomics. [Figure not available: see fulltext.

  19. Improved profiling of estrogen metabolites by orbitrap LC/MS

    Science.gov (United States)

    Li, Xingnan; Franke, Adrian A.

    2015-01-01

    Estrogen metabolites are important biomarkers to evaluate cancer risks and metabolic diseases. Due to their low physiological levels, a sensitive and accurate method is required, especially for the quantitation of unconjugated forms of endogenous steroids and their metabolites in humans. Here, we evaluated various derivatives of estrogens for improved analysis by orbitrap LC/MS in human serum samples. A new chemical derivatization reagent was applied modifying phenolic steroids to form 1-methylimidazole-2-sulfonyl adducts. The method significantly improves the sensitivity 2–100 fold by full scan MS and targeted selected ion monitoring MS over other derivatization methods including, dansyl, picolinoyl, and pyridine-3-sulfonyl products. PMID:25543003

  20. 76 FR 66931 - Medicare Program: Notice of Two Membership Appointments to the Advisory Panel on Ambulatory...

    Science.gov (United States)

    2011-10-28

    ...., FACHE.* David A. Halsey, M.D. Brian D. Kavanagh, M.D., MPH. Judith T. Kelly, R.H.I.T., R.H.I.A., C.C.S. Scott Manaker, M.D., Ph.D. John Marshall, CRA, RCC, CIRCC, RT(R), FAHRA. Agatha Nolan, D.Ph., M.S...

  1. MS Windows domēna darbstacijas migrācijas iespējas no MS Windows XP uz MS Windows 7.

    OpenAIRE

    Zariņš, Valdis

    2009-01-01

    Kvalifikācijas darbā tiek aprakstītas MS Windows domēna darbstacijas migrācijas iespējas no MS Windows XP uz MS Windows 7, kā servera operētājsistēmas izmantojot tādus Microsoft produktus, kā Microsoft Windows Server 2003 un Microsoft Windows Server 2008. Kvalifikācijas darba teorētiskaja daļā tiek apskatīti Microsoft Windows 7 priekšrocības un uzlabojumus gan no darbstacijas lietotāja , gan no darbstacijas administratora puses. Ir aprakstītas Microsoft Windows Server 2008 jauninājumu ie...

  2. Preclinical pharmacokinetic evaluation and metabolites identification of methyl salicylate-2-O-β-d-lactoside in rats using LC-MS/MS and Q-TOF-MS methods.

    Science.gov (United States)

    Zhang, Dan; Huang, Chao; Xin, Wenyu; Ma, Xiaowei; Zhang, Weiku; Zhang, Tiantai; Du, Guanhua

    2015-05-10

    Methyl salicylate-2-O-β-d-lactoside (MSL) is a natural salicylate derivative from the traditional Chinese medicine of Gaultheria yunnanensis (Franch.) Rehder (G. yunnanensis). As a non-steroidal anti-inflammatory drug (NSAID), MSL exerts a significant anti-arthritis effect but hardly has any gastrointestinal toxicity. In this paper, the pharmacokinetics, distribution, excretion and identification of MSL and its metabolites are described following rat oral and intravenous administration. The biological samples were quantified by UPLC-MS/MS and the metabolites in urine and feces were identified by using Q-TOF-MS. These results will support future investigations leading to clinical development of this drug. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Application of HRAM screening and LC-MS/MS confirmation of active pharmaceutical ingredient in "natural" herbal supplements.

    Science.gov (United States)

    Pascali, Jennifer P; Fais, Paolo; Vaiano, Fabio; Bertol, Elisabetta

    2018-05-01

    The growing market of herbal remedies worldwide could pose severe problems to consumers' health due to the possible presence of potentially harmful, undeclared synthetic substances or analogues of prescription drugs. The present work shows a simple but effective approach to unequivocally identify synthetic anorectic compounds in allegedly 'natural' herbal extracts, by exploiting liquid chromatography/time of flight (Q-TOF LC/MS) technology coupled to liquid chromatography/triple quadrupole (LC-MS/MS) confirmation and quantitation. The procedure was applied to five tea herbal extracts and pills sold as coadjutant for weigh loss. The method exploited liquid-liquid sample extraction (LLE) and separation in a C18 (2.1mm×150mm, 1.8μm) column. QTOF acquisitions were carried out both in scan mode and all ion MS/MS mode and results were obtained after search against ad hoc prepared library. Sibutramine, 4-hydroxyamphetamine, caffeine and theophylline were preliminary identified samples. Confirmation and quantitation of the preliminary identified compounds were obtained in LC-MS/MS after preparation of appropriated standards. Sibutramine, caffeine and theophylline were finally confirmed and quantitate. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Identification of alkyl dimethylbenzylammonium surfactants in water samples by solid-phase extraction followed by ion trap LC/MS and LC/MS/MS

    Science.gov (United States)

    Ferrer, I.; Furlong, E.T.

    2001-01-01

    A novel methodology was developed for the determination of alkyl (C12, C14, and C16) dimethylbenzylammonium chloride (benzalkonium chloride or BAC, Chemical Abstract Service number: 8001-54-5) in water samples. This method is based on solid-phase extraction (SPE) using polymeric cartridges, followed by high-performance liquid chromatography/ion trap mass spectrometry (LC/MS) and tandem mass spectrometry(MS/MS) detection, equipped with an electrospray interface in positive ion mode. Chromatographic separation was achieved for three BAC homologues by using a C18 column and a gradient of acetonitrile/10 millimolar aqueous ammonium formate. Total method recoveries were higher than 71% in different water matrices. The main ions observed by LC/MS were at mass-to-charge ratios (m/z) of 304, 332, and 360, which correspond to the molecular ions of the C12, C14, and C16 alkyl BAC, respectively. The unequivocal structural identification of these compounds in water samples was performed by LC/MS/MS after isolation and subsequent fragmentation of each molecular ion. The main fragmentation observed for the three different homologues corresponded to the loss of the toluyl group in the chemical structure, which leads to the fragment ions at m/z 212, 240, and 268 and a tropylium ion, characteristic of all homologues, at m/z 91. Detection limits for the methodology developed in this work were in the low nanogram-per-liter range. Concentration levels of BAC - ranging from 1.2 to 36.6 micrograms per liter - were found in surface-water samples collected downstream from different wastewater-treatment discharges, thus indicating its input and persistence through the wastewater-treatment process.

  5. Comprehensive analysis of proteins of pH fractionated samples using monolithic LC/MS/MS, intact MW measurement and MALDI-QIT-TOF MS

    Science.gov (United States)

    Yoo, Chul; Patwa, Tasneem H.; Kreunin, Paweena; Miller, Fred R.; Huber, Christian G.; Nesvizhskii, Alexey I.; Lubman, David M.

    2012-01-01

    A comprehensive platform that integrates information from the protein and peptide levels by combining various MS techniques has been employed for the analysis of proteins in fully malignant human breast cancer cells. The cell lysates were subjected to chromatofocusing fractionation, followed by tryptic digestion of pH fractions for on-line monolithic RP-HPLC interfaced with linear ion trap MS analysis for rapid protein identification. This unique approach of direct analysis of pH fractions resulted in the identification of large numbers of proteins from several selected pH fractions, in which approximately 1.5 μg of each of the pH fraction digests was consumed for an analysis time of ca 50 min. In order to combine valuable information retained at the protein level with the protein identifications obtained from the peptide level information, the same pH fraction was analyzed using nonporous (NPS)-RP-HPLC/ESI-TOF MS to obtain intact protein MW measurements. In order to further validate the protein identification procedures from the fraction digest analysis, NPS-RP-HPLC separation was performed for off-line protein collection to closely examine each protein using MALDI-TOF MS and MALDI-quadrupole ion trap (QIT)-TOF MS, and excellent agreement of protein identifications was consistently observed. It was also observed that the comparison to intact MW and other MS information was particularly useful for analyzing proteins whose identifications were suggested by one sequenced peptide from fraction digest analysis. PMID:17206599

  6. Determination of higenamine in dietary supplements by UHPLC/MS/MS method.

    Science.gov (United States)

    Stajić, A; Anđelković, M; Dikić, N; Rašić, J; Vukašinović-Vesić, M; Ivanović, D; Jančić-Stojanović, B

    2017-11-30

    From 1st January 2017 higenamine was added on the WADA (World Anti-doping Agency) Prohibited list under S3 group beta-2 agonists as at all times banned substance for the athletes. The main origine of higenamine (or norcoclaurine) are different plants including Nandina domestica, Aconitum carmichaelii, Asarum heterotropioides, Galium divaricatum, Annona squamosa, Nelumbo nucifera etc. Higenamine main use is related to weight loss and it could be found (un)labeled in different dietary supplements. The objective of this study was development of sensitive and reliable UHPLC/MS/MS method for determination of higenamine in various dietary supplement samples. In order to obtain high method sensitivity, hydrophilic interaction liquid chromatography (HILIC) mode was applied. Separation was carried out on UHPLC Acquity BEH HILIC analytical column (2.1mm×100mm, 1.7μm particle size). Mobile phase consisted of 0.1% formic acid in water and acetonitrile, respectively, was mixed in ratio of 30:70, v/v. Flow rate was set at 0.2mLmin -1 . Quercetin was used as an internal standard. ESI (+) source ionization mode using multi reaction monitoring (MRM) mode was utilized and three ion transitions of higenamine were followed 272.08→107.01, 272.08→161.07 and 272.08→77.08. Developed method was fully validated and applied for identification and quantification of higenamine in different dietary supplements. According to the results, the most of investigated supplements were free of higenamine, and on the other hand, presence of higenamine was confirmed in some samples while it was not declared on the label. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Screening and Identification of Mitragynine and 7-Hydroxymitragynine in Human Urine by LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Hanzhuo Fu

    2015-05-01

    Full Text Available Kratom is a tree planted in Southeast Asia, including Thailand, Malaysia, Myanmar (Burma and elsewhere in the region. A long history of usage and abuse of kratom has led to the classification of kratom as a controlled substance in its native Thailand and other Southeast Asian countries. However, kratom is not controlled in the United States, and the wide availability of kratom on the Internet and in the streets has led to its emergence as an herbal drug of misuse. With the increasing popularity of kratom, efficient protocols are needed to detect kratom use. In this study, a rapid method for the analysis of kratom compounds, mitragynine and 7-hydroxymitragynine, in human urine has been developed and validated using high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS. The chromatographic system employed a 2.6-μm 100 mm × 2.1 mm phenyl-hexyl analytical column and gradient elution with a 0.4-mL/min flow rate of water and acetonitrile as mobile phases. A triple quadrupole mass spectrometer was used as the detector for data acquisition. The analyst was the quantification software. The established method demonstrated linearity of >0.99 for both analytes, and low detection limits were obtained down to 0.002581 ng/mL for mitragynine and 0.06910 ng/mL for 7-hydroxymitragynine. The validated method has been utilized for clinical analysis of urine for the purpose of mitragynine and 7-hydroxymitragynine detection.

  8. Dried blood spot analysis of creatinine with LC-MS/MS in addition to immunosuppressants analysis.

    Science.gov (United States)

    Koster, Remco A; Greijdanus, Ben; Alffenaar, Jan-Willem C; Touw, Daan J

    2015-02-01

    In order to monitor creatinine levels or to adjust the dosage of renally excreted or nephrotoxic drugs, the analysis of creatinine in dried blood spots (DBS) could be a useful addition to DBS analysis. We developed a LC-MS/MS method for the analysis of creatinine in the same DBS extract that was used for the analysis of tacrolimus, sirolimus, everolimus, and cyclosporine A in transplant patients with the use of Whatman FTA DMPK-C cards. The method was validated using three different strategies: a seven-point calibration curve using the intercept of the calibration to correct for the natural presence of creatinine in reference samples, a one-point calibration curve at an extremely high concentration in order to diminish the contribution of the natural presence of creatinine, and the use of creatinine-[(2)H3] with an eight-point calibration curve. The validated range for creatinine was 120 to 480 μmol/L (seven-point calibration curve), 116 to 7000 μmol/L (1-point calibration curve), and 1.00 to 400.0 μmol/L for creatinine-[(2)H3] (eight-point calibration curve). The precision and accuracy results for all three validations showed a maximum CV of 14.0% and a maximum bias of -5.9%. Creatinine in DBS was found stable at ambient temperature and 32 °C for 1 week and at -20 °C for 29 weeks. Good correlations were observed between patient DBS samples and routine enzymatic plasma analysis and showed the capability of the DBS method to be used as an alternative for creatinine plasma measurement.

  9. An improved UPLC-MS/MS platform for quantitative analysis of glycerophosphoinositol in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Laura Grauso

    Full Text Available The glycerophosphoinositols constitute a class of biologically active lipid-derived mediators whose intracellular levels are modulated during physiological and pathological cell processes. Comprehensive assessment of the role of these compounds expands beyond the cellular biology of lipids and includes rapid and unambiguous measurement in cells and tissues. Here we describe a sensitive and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS method for quantitative analysis of the most abundant among these phosphoinositide derivatives in mammalian cells, the glycerophosphoinositol (GroPIns. The method has been developed in mouse Raw 264.7 macrophages with limits of quantitation at 3 ng/ml. Validation on the same cell line showed excellent response in terms of linear dynamic range (from 3 to 3,000 ng/ml, intra-day and inter-day precision (coefficient of variation ≤ 7.10% and accuracy (between 98.1 and 109.0% in the range 10-320 ng/ml. As proof of concept, a simplified analytical platform based on this method and external calibration was also tested on four stimulated and unstimulated cell lines, including Raw 264.7 macrophages, Jurkat T-cells, A375MM melanoma cells and rat basophilic leukemia RBL-2H3 cells. The results indicate a wide variation in GroPIns levels among different cell lines and stimulation conditions, although the measurements were always in line with the literature. No significant matrix effects were observed thus indicating that the here proposed method can be of general use for similar determinations in cells of different origin.

  10. Multielement analysis of Zanthoxylum bungeanum Maxim. essential oil using ICP-MS/MS.

    Science.gov (United States)

    Fu, Liang; Xie, Hualin; Shi, Shuyun

    2018-04-12

    The concentrations of trace elements (Cr, Ni, As, Cd, Hg, and Pb) in Zanthoxylum bungeanum Maxim. essential oil (ZBMEO) were determined by inductively coupled plasma tandem mass spectrometry. The ZBMEO sample was directly analyzed after simple dilution with n-hexane. Aiming for a relatively high vapor pressure of n-hexane and its resultant loading on plasma, we used a narrow injector torch and optimized plasma radio frequency power and carrier gas flow to ensure stable operation of the plasma. An optional gas flow of 20% O 2 in Ar was added to the carrier gas to prevent the incomplete combustion of highly concentrated organic carbon in plasma and the deposition of carbon on the sampling and skimmer cone orifices. In tandem mass spectrometry mode, O 2 was added to the collision/reaction cell to eliminate the interferences. The limits of detection for Cr, Ni, As, Cd, Hg, and Pb were 2.26, 1.64, 2.02, 1.35, 1.76, and 0.97 ng L -1 , respectively. After determination of 23 ZBMEO samples from different regions in China, we found that the average concentration ranges of trace elements in the 23 ZBMEO samples were 0.72-6.02 ng g -1 , 0.09-2.87 ng g -1 , 0.21-5.84 ng g -1 , 0.16-2.15 ng g -1 , 0.13-0.92 ng g -1 , and 0.17-0.73 ng g -1 for Cr, Ni, As, Cd, Hg, and Pb, respectively. The trace elements in ZBMEO differed significantly when different extraction technologies were used. The study revealed that the contents of the toxic elements As, Cd, Hg, and Pb were extremely low, and hence they are unlikely to pose a health risk following ZBMEO ingestion. Graphical abstract The working mechanism of sample analysis by ICP-MS/MS.

  11. Highly sensitive and specific derivatization strategy to profile and quantitate eicosanoids by UPLC-MS/MS

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Ting; Tie, Cai; Wang, Zhe; Zhang, Jin-Lan, E-mail: zhjl@imm.ac.cn

    2017-01-15

    Eicosanoids are signaling molecules mainly oxidized from arachidonic acid (ARA) and eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). They have attracted increasing attention from the scientists attributing to their essential physiological functions. However, their quantification have long been challenged by the low abundance, high structure similarity, poor stability and limited ionization efficiency. In this paper, an ultra-high performance liquid chromatograph coupled with tandem mass spectrometry (UPLC-MS/MS) strategy was developed for the comprehensive profiling of more than 60 eicosanoids based on an efficient derivatization reagent 2,4-bis(diethylamino)-6-hydrazino-1,3,5-triazine (T3) and general multiple reaction monitoring (MRM) parameters. Carboxylic acid of eicosanoid was converted to amide in 30 min at 4 °C with derivatization yield larger than 99%. Limits of quantitation (LOQs) for derivatized eicosanoids varied from 0.05 to 50 pg depending on their structures. The sensitivities of derivatized eicosanoids were enhanced by 10- to 5000-folds compared to free eicosanoids. Stabilities of T3 modified eicosanoids were also highly improved compared to free eicosanoids. This new method can also be used to quantify eicosanoids in bio-samples using isotopic internal standards with high efficiency and reliability within 19 min. 46 and 50 eicosanoids in rat plasma and heart tissue from control and acute myocardial ischemia (AMI) model rats were respectively profiled and quantitated using this new method. And 24 of 46 and 25 of 50 eicosanoids were found to be significantly changed between control and model groups. The changed eicosanoids related to AMI modeling were further statistically analyzed and interpreted based on eicosanoid metabolism pathway. - Highlights: • Eicosanoids are important signaling molecules. • A highly sensitive and specific derivatization strategy was developed for eicosanoid profiling. • The strategy was employed for

  12. Highly sensitive and specific derivatization strategy to profile and quantitate eicosanoids by UPLC-MS/MS

    International Nuclear Information System (INIS)

    Hu, Ting; Tie, Cai; Wang, Zhe; Zhang, Jin-Lan

    2017-01-01

    Eicosanoids are signaling molecules mainly oxidized from arachidonic acid (ARA) and eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). They have attracted increasing attention from the scientists attributing to their essential physiological functions. However, their quantification have long been challenged by the low abundance, high structure similarity, poor stability and limited ionization efficiency. In this paper, an ultra-high performance liquid chromatograph coupled with tandem mass spectrometry (UPLC-MS/MS) strategy was developed for the comprehensive profiling of more than 60 eicosanoids based on an efficient derivatization reagent 2,4-bis(diethylamino)-6-hydrazino-1,3,5-triazine (T3) and general multiple reaction monitoring (MRM) parameters. Carboxylic acid of eicosanoid was converted to amide in 30 min at 4 °C with derivatization yield larger than 99%. Limits of quantitation (LOQs) for derivatized eicosanoids varied from 0.05 to 50 pg depending on their structures. The sensitivities of derivatized eicosanoids were enhanced by 10- to 5000-folds compared to free eicosanoids. Stabilities of T3 modified eicosanoids were also highly improved compared to free eicosanoids. This new method can also be used to quantify eicosanoids in bio-samples using isotopic internal standards with high efficiency and reliability within 19 min. 46 and 50 eicosanoids in rat plasma and heart tissue from control and acute myocardial ischemia (AMI) model rats were respectively profiled and quantitated using this new method. And 24 of 46 and 25 of 50 eicosanoids were found to be significantly changed between control and model groups. The changed eicosanoids related to AMI modeling were further statistically analyzed and interpreted based on eicosanoid metabolism pathway. - Highlights: • Eicosanoids are important signaling molecules. • A highly sensitive and specific derivatization strategy was developed for eicosanoid profiling. • The strategy was employed for

  13. Quantitative monitoring of corticosteroids in cosmetic products manufactured in Korea using LC-MS/MS.

    Science.gov (United States)

    Nam, Yun Sik; Kwon, Il Keun; Lee, Yeonhee; Lee, Kang-Bong

    2012-07-10

    Some cosmetic products manufactured in Korea for the treatment of eczema, seborrhea and psoriasis have been suspected to contain anti-inflammatory corticosteroids such as prednisolone, hydrocortisone, betamethasone, dexamethasone and triamcinolone acetonide without these ingredients being indicated on the label. Due to their severe side effects such as permenent skin atopy, these corticosteroids have to be monitored in cosmetic products from a forensic point of view. Many cosmetic product samples (N=65) have been collected from both local and online markets in Korea. The corticosteroid content of these samples was analyzed by LC-MS/MS with diagnostic ions (m/z). Linearity was studied with 0.1-10 μg/mL range in all corticosteroids. Good correlation coefficients (r(2)≥0.997) were found and the limits of quantification were 4.68-7.97 ng/mL for each of the corticosteroids. At three different concentrations spanning the linear dynamic ranges, mean recoveries were 97.2-113.5%and precisions (RSD) for intra-day and inter-day analysis were less than 8.9%. Also, accuracy (Bias %) was less than 11.8%. The results showed that between 0.76-0.94 μg/g levels of prednisolone were detected in four cosmetic products and triamcinolone acetonidewas detected with a concentration in the range of 11.5-272 μg/g in nine samples. This fact reveals that some manufacturers have arbitrarily added these corticosteroids in their cosmetic products without indicating them on the label. Thus, these cosmetic products have to be monitored and if proven illegal preparations removed from the market. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  14. Chemical characterization of neonicotinoids in surface waters by high performance liquid chromatography with Tandem Mass Spectrometry (HPLC MS/MS)

    International Nuclear Information System (INIS)

    Amaral, Priscila Oliveira

    2017-01-01

    The present study aimed to develop a method for the determination and validation of a method for the identification and quantification of Neonicotinoids in surface waters collected in the Bauru region, in the state of São Paulo. The analytical techniques studied for the development of this method were the high performance liquid chromatography with tandem mass spectrometry (HPLC - MS / MS), gas chromatography with mass spectrometry (GC / MS) and gas chromatography with electron capture detector (GC / ECD). The class of pesticides Neonicotinoids was chosen for this work because it is related to a sudden disappearance of bees in colonies around the world. This phenomenon is known as Colony Collapse Disorder (CCD) and it is characterized by a rapid loss in the population of adult bees. The Neonicotinoids used in this study were the compounds Clothianidin, Imidacloprid and Thiamethoxam which were banned in their use as pesticides in Europe by Implementing Regulation No. 540/2011. The samples were concentrated using solid phase extraction (SPE) and liquid liquid extraction (LLE) techniques and injected into HPLC-MS / MS, GC / MS and GC / ECD. The GC / ECD and GC / MS techniques were not satisfactory for determination in the water matrix because the detection limit (10 mg L -1 ) is above the maximum allowed by the US Environmental Protection Agency (0.6 μg L -1 ). The HPLC - MS / MS technique using the multiple reaction monitoring (MRM) proved to be adequate for this study because it obtained quantification limits between 5.89 and 8.06 μg L -1 and a linearity between 0.9963 and 0.9999 for the three compounds. (author)

  15. What Is in Your Wallet? Quantitation of Drugs of Abuse on Paper Currency with a Rapid LC-MS/MS Method

    Science.gov (United States)

    Parker, Patrick D.; Beers, Brandon; Vergne, Matthew J.

    2017-01-01

    Laboratory experiments were developed to introduce students to the quantitation of drugs of abuse by high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). Undergraduate students were introduced to internal standard quantitation and the LC-MS/MS method optimization for cocaine. Cocaine extracted from paper currency was…

  16. METHOD 544. DETERMINATION OF MICROCYSTINS AND NODULARIN IN DRINKING WATER BY SOLID PHASE EXTRACTION AND LIQUID CHROMATOGRAPHY/TANDEM MASS SPECTROMETRY (LC/MS/MS)

    Science.gov (United States)

    Method 544 is an accurate and precise analytical method to determine six microcystins (including MC-LR) and nodularin in drinking water using solid phase extraction and liquid chromatography tandem mass spectrometry (SPE-LC/MS/MS). The advantage of this SPE-LC/MS/MS is its sensi...

  17. Vitamin D and Multiple Sclerosis (MS): Is There Any Connection?

    Science.gov (United States)

    ... there any connection? Is there any proof that vitamin D supplements can prevent MS or keep symptoms ... School have suggested that maintaining adequate levels of vitamin D may have a protective effect and lower ...

  18. Practical guide to ICP-MS: a tutorial for beginners

    National Research Council Canada - National Science Library

    Thomas, Robert

    2013-01-01

    ... for those with limited knowledge of the technique. Written by an insider with more than 20 years experience in product development, customer support, and technical marketing for an ICP-MS instrument vendor, the book highlights this powerful ultra...

  19. CE-MS fingerprinting of Laurencia complex algae (Rhodophyta).

    Science.gov (United States)

    Machín-Sánchez, María; Asensio-Ramos, María; Hernández-Borges, Javier; Gil-Rodríguez, María Candelaria

    2014-03-01

    The use of CE-ESI-MS has been considered as a new chemical strategy for the possible discernment of genera and species of the Laurencia complex. After the selection of the CE-MS and the extraction conditions, a total of 28 specimens of the complex, including different species of four genera (Laurencia, Laurenciella, Palisada, and Osmundea) collected from five intertidal locations on the Island of Tenerife (Canary Islands, Spain) were analyzed. CE-MS fingerprints revealed that CE-MS can be used as a useful tool for these studies in order to assess similarities and differences between them and that it constitutes an important starting point for further studies in the field. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Analysis of pesticides in fruit, vegetables and cereals using methanolic extraction and detection by LC-MS/MS

    DEFF Research Database (Denmark)

    Granby, Kit; Andersen, Jens Hinge; Christensen, Hanne Bjerre

    2004-01-01

    Abstract: A method for analysing carbamates and other relatively polar pesticides by LC–MS–MS with electrospray ionisation has been developed. The method is based on extraction by ultrasonication using a methanolic ammonium acetate–acetic acid buffer. After centrifugation the samples are filtered...... in Miniprep filter HPLC vials and detected by LC–MS–MS. To compensate for variations in the MS response [13C6]-carbaryl was used as internal standard and matrix-matched pesticide solutions were used as external standards for the quantification. The method has been validated for the matrices apple, avocado...

  1. Social cognition in pediatric-onset multiple sclerosis (MS).

    Science.gov (United States)

    Charvet, L E; Cleary, R E; Vazquez, K; Belman, A L; Krupp, L B

    2014-10-01

    Pediatric-onset multiple sclerosis (MS) patients represent a subpopulation who are diagnosed during the course of development. Social cognitive deficits have recently been recognized in adults with MS. It is critical to identify whether these youngest patients with the disorder are also at risk. To determine whether pediatric-onset MS is associated with social cognitive deficits. Consecutively-recruited participants with pediatric-onset MS were compared to a group of age- and gender-matched healthy controls on Theory of Mind (ToM) task performance. Tasks measured facial affect recognition (Reading the Mind in the Eyes Test), detecting social faux pas (Faux Pas Test), and understanding the perspective of another (False Beliefs Task). Twenty-eight (28) pediatric-onset MS participants (median age 17 years) and 32 healthy controls (median age 16 years) completed the study. The MS participants performed worse than controls on all three ToM tasks: Reading the Mind in the Eyes Test (p = 0.008), the Faux Pas Test (p = 0.009), and the False Beliefs Task (p = 0.06). While more MS than control participants were impaired on a measure of information processing speed (the Symbol Digit Modalities Test; 38% versus 6%), it did not account for the differences in ToM performance. Social cognition may represent an area of cognitive functioning affected by MS in the pediatric-onset population. These processes are especially important to study in younger patients as they may have long range implications for social adjustment, employment, and well-being. © The Author(s) 2014.

  2. The multiple sclerosis visual pathway cohort: understanding neurodegeneration in MS.

    Science.gov (United States)

    Martínez-Lapiscina, Elena H; Fraga-Pumar, Elena; Gabilondo, Iñigo; Martínez-Heras, Eloy; Torres-Torres, Ruben; Ortiz-Pérez, Santiago; Llufriu, Sara; Tercero, Ana; Andorra, Magi; Roca, Marc Figueras; Lampert, Erika; Zubizarreta, Irati; Saiz, Albert; Sanchez-Dalmau, Bernardo; Villoslada, Pablo

    2014-12-15

    Multiple Sclerosis (MS) is an immune-mediated disease of the Central Nervous System with two major underlying etiopathogenic processes: inflammation and neurodegeneration. The latter determines the prognosis of this disease. MS is the main cause of non-traumatic disability in middle-aged populations. The MS-VisualPath Cohort was set up to study the neurodegenerative component of MS using advanced imaging techniques by focusing on analysis of the visual pathway in a middle-aged MS population in Barcelona, Spain. We started the recruitment of patients in the early phase of MS in 2010 and it remains permanently open. All patients undergo a complete neurological and ophthalmological examination including measurements of physical and disability (Expanded Disability Status Scale; Multiple Sclerosis Functional Composite and neuropsychological tests), disease activity (relapses) and visual function testing (visual acuity, color vision and visual field). The MS-VisualPath protocol also assesses the presence of anxiety and depressive symptoms (Hospital Anxiety and Depression Scale), general quality of life (SF-36) and visual quality of life (25-Item National Eye Institute Visual Function Questionnaire with the 10-Item Neuro-Ophthalmic Supplement). In addition, the imaging protocol includes both retinal (Optical Coherence Tomography and Wide-Field Fundus Imaging) and brain imaging (Magnetic Resonance Imaging). Finally, multifocal Visual Evoked Potentials are used to perform neurophysiological assessment of the visual pathway. The analysis of the visual pathway with advance imaging and electrophysilogical tools in parallel with clinical information will provide significant and new knowledge regarding neurodegeneration in MS and provide new clinical and imaging biomarkers to help monitor disease progression in these patients.

  3. The utility of ultra-high performance supercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) for clinically relevant steroid analysis.

    Science.gov (United States)

    Storbeck, Karl-Heinz; Gilligan, Lorna; Jenkinson, Carl; Baranowski, Elizabeth S; Quanson, Jonathan L; Arlt, Wiebke; Taylor, Angela E

    2018-05-15

    Liquid chromatography tandem mass spectrometry (LC-MS/MS) assays are considered the reference standard for serum steroid hormone analyses, while full urinary steroid profiles are only achievable by gas chromatography (GC-MS). Both LC-MS/MS and GC-MS have well documented strengths and limitations. Recently, commercial ultra-high performance supercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) systems have been developed. These systems combine the resolution of GC with the high-throughput capabilities of UHPLC. Uptake of this new technology into research and clinical labs has been slow, possibly due to the perceived increase in complexity. Here we therefore present fundamental principles of UHPSFC-MS/MS and the likely applications for this technology in the clinical research setting, while commenting on potential hurdles based on our experience to date. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  4. Laser ablation ICP-MS for quantitative biomedical applications

    International Nuclear Information System (INIS)

    Konz, Ioana; Fernandez, Beatriz; Fernandez, M.L.; Pereiro, Rosario; Sanz-Medel, Alfredo

    2012-01-01

    LA-ICP-MS allows precise, relatively fast, and spatially resolved measurements of elements and isotope ratios at trace and ultratrace concentration levels with minimal sample preparation. Over the past few years this technique has undergone rapid development, and it has been increasingly applied in many different fields, including biological and medical research. The analysis of essential, toxic, and therapeutic metals, metalloids, and nonmetals in biomedical tissues is a key task in the life sciences today, and LA-ICP-MS has proven to be an excellent complement to the organic MS techniques that are much more commonly employed in the biomedical field. In order to provide an appraisal of the fast progress that is occurring in this field, this review critically describes new developments for LA-ICP-MS as well as the most important applications of LA-ICP-MS, with particular emphasis placed on the quantitative imaging of elements in biological tissues, the analysis of heteroatom-tagged proteins after their separation and purification by gel electrophoresis, and the analysis of proteins that do not naturally have ICP-MS-detectable elements in their structures, thus necessitating the use of labelling strategies. (orig.)

  5. Methylation-Sensitive High Resolution Melting (MS-HRM).

    Science.gov (United States)

    Hussmann, Dianna; Hansen, Lise Lotte

    2018-01-01

    Methylation-Sensitive High Resolution Melting (MS-HRM) is an in-tube, PCR-based method to detect methylation levels at specific loci of interest. A unique primer design facilitates a high sensitivity of the assays enabling detection of down to 0.1-1% methylated alleles in an unmethylated background.Primers for MS-HRM assays are designed to be complementary to the methylated allele, and a specific annealing temperature enables these primers to anneal both to the methylated and the unmethylated alleles thereby increasing the sensitivity of the assays. Bisulfite treatment of the DNA prior to performing MS-HRM ensures a different base composition between methylated and unmethylated DNA, which is used to separate the resulting amplicons by high resolution melting.The high sensitivity of MS-HRM has proven useful for detecting cancer biomarkers in a noninvasive manner in urine from bladder cancer patients, in stool from colorectal cancer patients, and in buccal mucosa from breast cancer patients. MS-HRM is a fast method to diagnose imprinted diseases and to clinically validate results from whole-epigenome studies. The ability to detect few copies of methylated DNA makes MS-HRM a key player in the quest for establishing links between environmental exposure, epigenetic changes, and disease.

  6. LSN MS guidelines for the management of multiple sclerosis.

    Science.gov (United States)

    Shatila, A R; Koussa, S; Jabbour, R; Mourad, A; Aouad, A; Sabbagh, G; Kallab, K; Hilal, R; Khalifeh, R; Gebeily, S; Tourbah, A

    2013-12-01

    The prevalence of multiple sclerosis (MS) in Lebanon is unknown, as there are no available or reliable epidemiological studies to date. The circumstances of Middle East countries are different from those of Europe and North America in terms of differential diagnoses and disease management. The aim of the conference is to establish guidelines for diagnosis, treatment, follow-up and management of patients with MS in Lebanon. Another objective is to discuss and participate in research projects based on epidemiology, clinical trials and more fundamental aspects of the disease in the future. Under the authority of the Lebanese Society of Neurology (LSN), a group of neurologists took the initiative to participate in this LSN MS committee with the purpose of establishing a consensus for the management of patients with MS, and under the supervision of a Coordinator (A.T.) designed by the LSN board. Diagnostic and therapeutic, follow-up and research recommendations were proposed with special emphasis on the specific needs and circumstances of Lebanon. The experts highlighted the importance of considering particular needs, the identification of patients at high risk of developing MS in order to maximize therapeutic opportunities, and cost-effective control of treatment efficacy, as well as global assessment of disability. The experts established guidelines concerning diagnosis, treatment, and follow-up of patients with MS in Lebanon. Furthermore, they recommended some clinical and fundamental research projects. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  7. Demographic characteristics of MS patients in Poland's upper Silesia region.

    Science.gov (United States)

    Pierzchala, Krystyna; Adamczyk-Sowa, Monika; Dobrakowski, Pawel; Kubicka-Baczyk, Katarzyna; Niedziela, Natalia; Sowa, Pawel

    2015-05-01

    In Poland, no national registry of MS patients has yet been introduced. So far, no demographic studies have been conducted in patients with MS in Upper Silesia. The aim of the present study was to evaluate, for the first time, a selected demographic and clinical parameters in MS patients from the Upper Silesia region and compare these characteristics with previously published data from other regions of Poland. 640 patients with clinically defined MS, were prospectively and randomly selected for the study. Social, socio-economic, and demographic data were obtained through a questionnaire study. All subjects performed a self-assessment of their health condition using EQ-5D and EQ-VAS version questionnaires. The ratio of women to men was 2.18. The average age of onset was 29.6 ± 11.1 years; the disease duration was 7.9 ± 4.5 years. The relapsing-remitting form of MS was diagnosed in 73.12%. In 71.25% the onset was monofocal and in 28.75% multifocal disease onset was observed. Among the studied population 339 (52.97%) patients were still employed. A mean EQ-VAS score of 66.11 ± 20.12 was calculated. Results from our study identify for the first time the demographic and clinical characteristics of the Upper Silesia MS population.

  8. Inductively coupled plasma mass spectrometry (ICP-MS)

    International Nuclear Information System (INIS)

    Shimamura, Tadashi

    1997-01-01

    The period of investigation for the previous general remarks on the progress of ICP-MS was from January, 1991 to September, 1993. In the investigation of this time, for the object of the Chemical Abstracts from January, 1994 to September, 1996, retrieval was carried out by using the STN International. As the key words, ICP-MS, Inductively Coupled Plasma Mass Spectrometry or Inductively Coupled Plasma Mass Spectrometer was used. The number of hit was 373 in 1994, 462 in 1995, and 356 as of September, 1996, 1191 in total. The cumulative number of the papers from 1980 to 1996 is shown. It is known how rapidly the ICP-MS has pervaded as the means of analysis. In order to cope with the enormous number of papers, this time, it was decided to do the review by limiting to the papers which were published in the main journals deeply related to analytical chemistry. As to the tendency in the last three years, it is summarized as how to overcome the spectrum interference and matrix effect in the ICP-MS and the trend of using the ICP-MS as the high sensitivity detector for separation techniques. The technical basic research of the ICP-MS on spectrum interference, sample introduction method and others and the analysis of living body samples are reported. (K.I.)

  9. Comparing depression screening tools in persons with multiple sclerosis (MS).

    Science.gov (United States)

    Hanna, Joshua; Santo, Jonathan B; Blair, Mervin; Smolewska, Kathy; Warriner, Erin; Morrow, Sarah A

    2017-02-01

    Depression is more common among persons with multiple sclerosis (MS) than the general population. Depression in MS is associated with reduced quality of life, transition to unemployment, and cognitive impairment. Two proposed screening measures for depression in MS populations are the Hospital Anxiety and Depression Scale (HADS) and the Beck Depression Inventory-Fast Screen (BDI-FS). Our objective was to compared the associations of the BDI-FS and the HADS-D scores with history of depressive symptoms, fatigue, and functional outcomes to determine the differential clinical utility of these screening measures among persons with MS. We reviewed charts of 133 persons with MS for demographic information; scores on the HADS, BDI-FS, a fatigue measure, and a processing speed measure; and employment status. Structural equation modeling results indicated the HADS-D predicted employment status, disability status, and processing speed more effectively than did the BDI-FS, whereas both measures predicted fatigue. This study suggests the HADS-D is more effective than the BDI-FS in predicting functional outcomes known to be associated with depression among persons with MS. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. Quantitation of iothalamate in urine and plasma using liquid chromatography electrospray tandem mass spectrometry (HPLC-ESI-MS/MS).

    Science.gov (United States)

    Molinaro, Ross J; Ritchie, James C

    2010-01-01

    The following chapter describes a method to measure iothalamate in plasma and urine samples using high performance liquid chromatography combined with electrospray positive ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Methanol and water are spiked with the internal standard (IS) iohexol. Iothalamate is isolated from plasma after IS spiked methanol extraction and from urine by IS spiked water addition and quick-spin filtration. The plasma extractions are dried under a stream of nitrogen. The residue is reconstituted in ammonium acetate-formic acid-water. The reconstituted plasma and filtered urine are injected into the HPLC-ESI-MS/MS. Iothalamate and iohexol show similar retention times in plasma and urine. Quantification of iothalamate in the samples is made by multiple reaction monitoring using the hydrogen adduct mass transitions, from a five-point calibration curve.

  11. Post-acquisition data mining techniques for LC-MS/MS-acquired data in drug metabolite identification.

    Science.gov (United States)

    Dhurjad, Pooja Sukhdev; Marothu, Vamsi Krishna; Rathod, Rajeshwari

    2017-08-01

    Metabolite identification is a crucial part of the drug discovery process. LC-MS/MS-based metabolite identification has gained widespread use, but the data acquired by the LC-MS/MS instrument is complex, and thus the interpretation of data becomes troublesome. Fortunately, advancements in data mining techniques have simplified the process of data interpretation with improved mass accuracy and provide a potentially selective, sensitive, accurate and comprehensive way for metabolite identification. In this review, we have discussed the targeted (extracted ion chromatogram, mass defect filter, product ion filter, neutral loss filter and isotope pattern filter) and untargeted (control sample comparison, background subtraction and metabolomic approaches) post-acquisition data mining techniques, which facilitate the drug metabolite identification. We have also discussed the importance of integrated data mining strategy.

  12. Development of an LC-MS/MS method for the determination of pesticides and patulin in apples

    DEFF Research Database (Denmark)

    Christensen, Hanne Bjerre; Poulsen, Mette Erecius; Rasmussen, Peter Have

    2009-01-01

    A method for the simultaneous determination of 33 pesticides or degradation products together with patulin in apples by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. The method involved homogenization of the apples, extraction with ammonium acetate-acetic acid solution...... in methanol-water by ultrasonication, filtration, and determination by LC-MS/MS. The repeatability and within-laboratory reproducibility for the three spiking levels 0.02, 0.04 and 0.2 mg kg(-1) were between 4% and 35%. In general, the repeatability and reproducibility were about 10-20%. The limits...... of quantification (LOQs) were between 0.01 and 0.14 mg kg(-1). The method was used on incurred samples from parts of the ISAFRUIT project financed by the European Commission under the 6th Framework Programme. Samples were analysed at four different stages: after harvest, after storage (controlled), after a water...

  13. Complex mixture analysis of peptides using LC/LC-MS/MS and data-dependent protein identification

    International Nuclear Information System (INIS)

    Wasinger, V.; Corthals, G.

    2001-01-01

    The comprehensive identification of proteins within complex solutions by mass-spectrometry largely depends on the sensitivity, resolving power and sampling efficiency of the technology. An integrated orthogonal approach using Strong Cation Exchange-Reverse Phase-MS/MS (SCX-RP-MS/MS) was used to evaluate the data-dependent Collision Induced Dissociation (CID) of yeast peptides. Reverse phase gradient times of 4, 10. 30, 90, and 180 minutes allowed the identification of hundreds of proteins in a nearly automated fashion from nuclear, membrane, and cytosolic distributions. Many proteins from typically difficult to resolve regions of two-dimensional gels, such as >100kDa, > pI 9.0 and Codon Adaptation Index < 0.2, were also identified using this multi-dimensional separation technology. Few low mass proteins (<10kDa) were identified. The impact of scan-range and duty-cycle on CID of peptides will be discussed

  14. Detection of mono- and di-hexoses as metabolites of 4-bromoaniline using HPLC-TOF-MS/MS.

    Science.gov (United States)

    Major, H; Castro-Perez, J; Nicholson, J K; Wilson, I D

    2003-08-01

    1. The metabolic fate of 4-bromoaniline (4-BrA) was investigated in rat following intraperitoneal administration at 50 mg kg(-1) using HPLC-TOF-MS/MS. 2. The sensitivity provided by the use of TOF-MS/MS, aided by the distinctive isotope pattern resulting from the presence of the bromine substituent in the molecule, enabled the detection of many previously uncharacterized metabolites in the samples. 3. Several groups of minor metabolites were detected in the urine that corresponded to a number of isomeric hexose and di-hexose-containing conjugates (possibly glucosides and diglucosides) of 4-BrA. 4. As well as hexose and di-hexose conjugates of 4-BrA, several further groups of metabolites that also contained either a sulphamate or sulphate group in addition to the sugar moieties were also detected.

  15. Quantitation of dialkyl phosphate metabolites of organophosphate pesticides in human urine using GC-MS-MS with isotopic internal standards.

    Science.gov (United States)

    Bravo, Roberto; Driskell, William J; Whitehead, Ralph D; Needham, Larry L; Barr, Dana B

    2002-01-01

    Human exposure to organophosphate pesticides can be estimated from the presence of urinary metabolites. An isotope-dilution gas chromatography-tandem mass spectrometry (GC-MS-MS) method was developed for quantitating the six dialkyl phosphate urinary metabolites of at least 29 organophosphate pesticides. Urine samples were spiked with stable isotope analogues of the dialkyl phosphates, evaporated using azeotropic distillation, followed by chemical derivatization of the metabolites to their respective chloropropyl phosphate esters. The chloropropyl phosphate esters were concentrated and then analyzed using GC-MS-MS. The limits of detection (LODs) of the method were in the low-to-mid picogram-per-milliliter range (parts per trillion) with coefficients of variation of less than 20%. The use of stable isotope analogues as internal standards for each of these metabolites allows for the highest degree of accuracy and precision. Additionally, the low LODs allow the use of this method in general population studies.

  16. The EIPeptiDi tool: enhancing peptide discovery in ICAT-based LC MS/MS experiments

    Directory of Open Access Journals (Sweden)

    Tradigo Giuseppe

    2007-07-01

    Full Text Available Abstract Background Isotope-coded affinity tags (ICAT is a method for quantitative proteomics based on differential isotopic labeling, sample digestion and mass spectrometry (MS. The method allows the identification and relative quantification of proteins present in two samples and consists of the following phases. First, cysteine residues are either labeled using the ICAT Light or ICAT Heavy reagent (having identical chemical properties but different masses. Then, after whole sample digestion, the labeled peptides are captured selectively using the biotin tag contained in both ICAT reagents. Finally, the simplified peptide mixture is analyzed by nanoscale liquid chromatography-tandem mass spectrometry (LC-MS/MS. Nevertheless, the ICAT LC-MS/MS method still suffers from insufficient sample-to-sample reproducibility on peptide identification. In particular, the number and the type of peptides identified in different experiments can vary considerably and, thus, the statistical (comparative analysis of sample sets is very challenging. Low information overlap at the peptide and, consequently, at the protein level, is very detrimental in situations where the number of samples to be analyzed is high. Results We designed a method for improving the data processing and peptide identification in sample sets subjected to ICAT labeling and LC-MS/MS analysis, based on cross validating MS/MS results. Such a method has been implemented in a tool, called EIPeptiDi, which boosts the ICAT data analysis software improving peptide identification throughout the input data set. Heavy/Light (H/L pairs quantified but not identified by the MS/MS routine, are assigned to peptide sequences identified in other samples, by using similarity criteria based on chromatographic retention time and Heavy/Light mass attributes. EIPeptiDi significantly improves the number of identified peptides per sample, proving that the proposed method has a considerable impact on the protein

  17. Phenolic Profiling of Duchesnea indica Combining Macroporous Resin Chromatography (MRC with HPLC-ESI-MS/MS and ESI-IT-MS

    Directory of Open Access Journals (Sweden)

    Mingzhi Zhu

    2015-12-01

    Full Text Available Duchesnea indica (D. indica is an important traditional Chinese medicine, and has long been clinically used to treat cancer in Asian countries. It has been described previously as a rich source of phenolic compounds with a broad array of diversified structures, which are the major active ingredients. However, an accurate and complete phenolic profiling has not been determined yet. In the present work, the total phenolic compounds in crude extracts from D. indica were enriched and fractionated over a macroporous resin column, then identified by HPLC-ESI-MS/MS and ESI-IT-MS (ion trap MS. A total of 27 phenolic compounds were identified in D. indica, of which 21 compounds were identified for the first time. These 27 phenolic compounds encompassing four phenolic groups, including ellagitannins, ellagic acid and ellagic acid glycosides, hydroxybenzoic acid and hydroxycinnamic acid derivatives, and flavonols, were then successfully quantified using peak areas against those of the corresponding standards with good linearity (R2 > 0.998 in the range of the tested concentrations. As a result, the contents of individual phenolic compounds varied from 6.69 mg per 100 g dry weight (DW for ellagic acid to 71.36 mg per 100 g DW for brevifolin carboxylate. Not only did this study provide the first phenolic profiling of D. indica, but both the qualitative identification and the subsequent quantitative analysis of 27 phenolic compounds from D. indica should provide a good basis for future exploration of this valuable medicinal plant.

  18. LIQUID: an-open source software for identifying lipids in LC-MS/MS-based lipidomics data

    Energy Technology Data Exchange (ETDEWEB)

    Kyle, Jennifer E.; Crowell, Kevin L.; Casey, Cameron P.; Fujimoto, Grant M.; Kim, Sangtae; Dautel, Sydney E.; Smith, Richard D.; Payne, Samuel H.; Metz, Thomas O.

    2017-01-31

    We introduce an open-source software, LIQUID, for semi-automated processing and visualization of LC-MS/MS based lipidomics data. LIQUID provides users with the capability to process high throughput data and contains a customizable target library and scoring model per project needs. The graphical user interface provides visualization of multiple lines of spectral evidence for each lipid identification, allowing rapid examination of data for making confident identifications of lipid molecular species.

  19. Determination of isosteviol by LC-MS/MS and its application for evaluation of pharmacokinetics of isosteviol in rat

    Directory of Open Access Journals (Sweden)

    Bazargan M.

    2007-06-01

    Full Text Available Isosteviol has been found to have potential preventive or therapeutic effects against hypertension, ischemia reperfusion injury, diabetes and cancer, but little is known about the pharmacokinetics (PK of the compound. The aim of this study was to develop a liquid chromatographic-tandem mass spectrometric (LC-MS/MS method for determination of isosteviol in rat plasma and to assess in a preliminary manner the PK of isosteviol after intravenous bolus injection.Ions of analytes were generated using electro-spray ionization and detected in the positive-ion mode in LC-MS/MS. Multiple reaction monitoring was performed, using the precursor product ion combination for isosteviol m/z 319.4→273.4. Progesterone was used as an internal standard. Nitrogen was used as the nebulising gas and unit resolution was set for Q1 and Q3. Isosteviol solution was injected through the penile vein of rats at a dose of 8 mg/kg. Blood samples were collected from a jugular vein cannula. The PK parameters were calculated using a two - compartment PK model.The LC-MS/MS assay for isosteviol in rat plasma was linear over the range of 0.5-80 μg/ml. The terminal half life of isosteviol (t 1/2 was 406 ± 31.7 min and clearance (CL was 2.9 ± 0.3 ml/min/kg. A sensitive LC-MS/MS assay for isosteviol in plasma has been successfully established and used in a preliminary PK evaluation of isosteviol in rats.

  20. Effect of Genetics, Environment, and Phenotype on the Metabolome of Maize Hybrids Using GC/MS and LC/MS.

    Science.gov (United States)

    Tang, Weijuan; Hazebroek, Jan; Zhong, Cathy; Harp, Teresa; Vlahakis, Chris; Baumhover, Brian; Asiago, Vincent

    2017-06-28

    We evaluated the variability of metabolites in various maize hybrids due to the effect of environment, genotype, phenotype as well as the interaction of the first two factors. We analyzed 480 forage and the same number of grain samples from 21 genetically diverse non-GM Pioneer brand maize hybrids, including some with drought tolerance and viral resistance phenotypes, grown at eight North American locations. As complementary platforms, both GC/MS and LC/MS were utilized to detect a wide diversity of metabolites. GC/MS revealed 166 and 137 metabolites in forage and grain samples, respectively, while LC/MS captured 1341 and 635 metabolites in forage and grain samples, respectively. Univariate and multivariate analyses were utilized to investigate the response of the maize metabolome to the environment, genotype, phenotype, and their interaction. Based on combined percentages from GC/MS and LC/MS datasets, the environment affected 36% to 84% of forage metabolites, while less than 7% were affected by genotype. The environment affected 12% to 90% of grain metabolites, whereas less than 27% were affected by genotype. Less than 10% and 11% of the metabolites were affected by phenotype in forage and grain, respectively. Unsupervised PCA and HCA analyses revealed similar trends, i.e., environmental effect was much stronger than genotype or phenotype effects. On the basis of comparisons of disease tolerant and disease susceptible hybrids, neither forage nor grain samples originating from different locations showed obvious phenotype effects. Our findings demonstrate that the combination of GC/MS and LC/MS based metabolite profiling followed by broad statistical analysis is an effective approach to identify the relative impact of environmental, genetic and phenotypic effects on the forage and grain composition of maize hybrids.

  1. Temporal variation of gravity field prior to the Ludian Ms6.5 and Kangding Ms6.3 earthquakes

    OpenAIRE

    Hao, Hongtao; Wei, Jin; Hu, Minzhang; Liu, Ziwei; Li, Hui

    2015-01-01

    Using mobile gravity data from the central area of Sichuan and Yunnan Provinces, the relationship between gravity variation and earthquakes was studied based on the Ludian Ms6.5 earthquake that occurred on August 3rd, 2014, and the Kangding Ms6.3 earthquake that occurred on November 22nd, 2014; the mechanism of gravity variation was also explored. The results are as follows: (1) Prior to both earthquakes, gravity variation exhibited similar characteristics as those observed before both the Ta...

  2. Non-enzymolytic adenosine barcode-mediated dual signal amplification strategy for ultrasensitive protein detection using LC-MS/MS.

    Science.gov (United States)

    Yang, Wen; Li, Tengfei; Shu, Chang; Ji, Shunli; Wang, Lei; Wang, Yan; Li, Duo; Mtalimanja, Michael; Sun, Luning; Ding, Li

    2018-05-10

    A method is described for the determination of proteins with LC-MS/MS enabled by a small molecule (adenosine) barcode and based on a double-recognition sandwich structure. The coagulation protein thrombin was chosen as the model analyte. Magnetic nanoparticles were functionalized with aptamer29 (MNP/apt29) and used to capture thrombin from the samples. MNP/apt29 forms a sandwich with functionalized gold nanoparticles modified with (a) aptamer15 acting as thrombin-recognizing element and (b) a large number of adenosine as mass barcodes. The sandwich formed (MNP/apt29-thrombin-apt15/AuNP/adenosine) can ben magnetically separated from the sample. Mass barcodes are subsequently released from the sandwiched structure for further analysis by adding 11-mercaptoundecanoic acid. Adenosine is then detected by LC-MS/MS as it reflects the level of thrombin with impressively amplified signal. Numerous adenosines introduced into the sandwich proportional to the target concentration further amplify the signal. Under optimized conditions, the response is linearly proportional to the thrombin concentration in the range of 0.02 nM to 10 nM, with a detection limit of 9 fM. The application of this method to the determination of thrombin in spiked plasma samples gave recoveries that ranged from 92.3% to 104.7%. Graphical abstract Schematic representation of a method for the determination of thrombin with LC-MS/MS. The method is based on a double-recognition sandwiched structure. With LC-MS/MS, mass barcodes (adenosine) are detected to quantify thrombin, which amplifies the detection signal impressively.

  3. IsoMS: automated processing of LC-MS data generated by a chemical isotope labeling metabolomics platform.

    Science.gov (United States)

    Zhou, Ruokun; Tseng, Chiao-Li; Huan, Tao; Li, Liang

    2014-05-20

    A chemical isotope labeling or isotope coded derivatization (ICD) metabolomics platform uses a chemical derivatization method to introduce a mass tag to all of the metabolites having a common functional group (e.g., amine), followed by LC-MS analysis of the labeled metabolites. To apply this platform to metabolomics studies involving quantitative analysis of different groups of samples, automated data processing is required. Herein, we report a data processing method based on the use of a mass spectral feature unique to the chemical labeling approach, i.e., any differential-isotope-labeled metabolites are detected as peak pairs with a fixed mass difference in a mass spectrum. A software tool, IsoMS, has been developed to process the raw data generated from one or multiple LC-MS runs by peak picking, peak pairing, peak-pair filtering, and peak-pair intensity ratio calculation. The same peak pairs detected from multiple samples are then aligned to produce a CSV file that contains the metabolite information and peak ratios relative to a control (e.g., a pooled sample). This file can be readily exported for further data and statistical analysis, which is illustrated in an example of comparing the metabolomes of human urine samples collected before and after drinking coffee. To demonstrate that this method is reliable for data processing, five (13)C2-/(12)C2-dansyl labeled metabolite standards were analyzed by LC-MS. IsoMS was able to detect these metabolites correctly. In addition, in the analysis of a (13)C2-/(12)C2-dansyl labeled human urine, IsoMS detected 2044 peak pairs, and manual inspection of these peak pairs found 90 false peak pairs, representing a false positive rate of 4.4%. IsoMS for Windows running R is freely available for noncommercial use from www.mycompoundid.org/IsoMS.

  4. Wide-scope screening of pesticides in fruits and vegetables using information-dependent acquisition employing UHPLC-QTOF-MS and automated MS/MS library searching.

    Science.gov (United States)

    Wang, Zhibin; Cao, Yanzhong; Ge, Na; Liu, Xiaomao; Chang, Qiaoying; Fan, Chunlin; Pang, Guo-Fang

    2016-11-01

    This paper presents an application of ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) for simultaneous screening and identification of 427 pesticides in fresh fruit and vegetable samples. Both full MS scan mode for quantification, and an artificial-intelligence-based product ion scan mode information-dependent acquisition (IDA) providing automatic MS to MS/MS switching of product ion spectra for identification, were conducted by one injection. A home-in collision-induced-dissociation all product ions accurate mass spectra library containing more than 1700 spectra was developed prior to actual application. Both qualitative and quantitative validations of the method were carried out. The result showed that 97.4 % of the pesticides had the screening detection limit (SDL) less than 50 μg kg -1 and more than 86.7 % could be confirmed by accurate MS/MS spectra embodied in the home-made library. Meanwhile, calibration curves covering two orders of magnitude were performed, and they were linear over the concentration range studied for the selected matrices (from 5 to 500 μg kg -1 for most of the pesticides). Recoveries between 80 and 110 % in four matrices (apple, orange, tomato, and spinach) at two spiked levels, 10 and 100 μg kg -1 , was 88.7 or 86.8 %. Furthermore, the overall relative standard deviation (RSD, n = 12) for 94.3 % of the pesticides in 10 μg kg -1 and 98.1 % of the pesticides in 100 μg kg -1 spiked levels was less than 20 %. In order to validate the suitability for routine analysis, the method was applied to 448 fruit and vegetable samples purchased in different local markets. The results show 83.3 % of the analyzed samples have positive findings (higher than the limits of identification and quantification), and 412 commodity-pesticide combinations are identified in our scope. The approach proved to be a cost-effective, time-saving and powerful strategy for routine large

  5. HPLC-UV, MALDI-TOF-MS and ESI-MS/MS analysis of the mechlorethamine DNA crosslink at a cytosine-cytosine mismatch pair.

    Directory of Open Access Journals (Sweden)

    Pornchai Rojsitthisak

    Full Text Available Mechlorethamine [ClCH(2CH(2N(CH(3CH(2CH(2Cl], a nitrogen mustard alkylating agent, has been proven to form a DNA interstrand crosslink at a cytosine-cytosine (C-C mismatch pair using gel electrophoresis. However, the atomic connectivity of this unusual crosslink is unknown.HPLC-UV, MALDI-TOF-MS, and ESI-MS/MS were used to determine the atomic connectivity of the DNA C-C crosslink formed by mechlorethamine, MALDI-TOF-MS of the HPLC-purified reaction product of mechlorethamine with the DNA duplex d[CTCACACCGTGGTTC]•d[GAACCACCGTGTGAG] (underlined bases are a C-C mismatch pair indicated formation of an interstrand crosslink at m/z 9222.088 [M-2H+Na](+. Following enzymatic digestion of the crosslinked duplex by snake venom phosphodiesterase and calf intestinal phosphatase, ESI-MS/MS indicated the presence of dC-mech-dC [mech = CH(2CH(2N(CH(3CH(2CH(2] at m/z 269.2 [M](2+ (expected m/z 269.6, exact mass 539.27 and its hydrolytic product dC-mech-OH at m/z 329.6 [M](+ (expected m/z 329.2. Fragmentation of dC-mech-dC gave product ions at m/z 294.3 and 236.9 [M](+, which are both due to loss of the 4-amino group of cytosine (as ammonia, in addition to dC and dC+HN(CH(3CH = CH(2, respectively. The presence of m/z 269.2 [M](2+ and loss of ammonia exclude crosslink formation at cytosine N(4 or O(2 and indicate crosslinking through cytosine N(3 with formation of two quaternary ammonium ions.Our results provide an important addition to the literature, as the first example of the use of HPLC and MS for analysis of a DNA adduct at the N(3 position of cytosine.

  6. Die musiktheoretische Ergründung der Arienform in italienischen Opern des 18. Jahrhunderts und die Umgestaltung des Fachs Formenlehre

    Directory of Open Access Journals (Sweden)

    Irina Susidko

    2015-12-01

    Full Text Available The paper focuses on the issue of the role played by the 18th Century Italian aria within the general system of musical forms. This question is relevant for both music theory and pedagogy. Did the aria influence instrumental genres or was it the opposite?Throughout the history of professional musical education in Russia (from the 19th century to the present day, both general music theory and courses in musical form have usually been based on instrumental music. However, studies in recent decades show that, in the process of crystallization of a number of structures and principles of composition in the first half of the 18th century, the aria takes a prominent position. Among these are such principles as the ritornello, which underlies the Baroque concerto; principles of recapitulation and ternary form that became established in Italian arias in the 1680s (earlier than in the instrumental genres, as well as the principle of thematic contrast. Italian opera played a key role in the formation of classical musical Thematik (Ger. - not only in its lexical topoi, but also in the treatment of homophony, metric and syntactic periodicity, and the fractionality of motivic structure. The development of the two-subjects sonata form took place within the framework of da capo arias simultaneously with instrumental music (1720-1750s. The Italian aria played a decisive role in the birth of the sonata form with two initial sections typical of the classic concerto.In the musical form course for musicologists and musicians-performers at the Russian Gnessins Academy of Music, I discuss the theory and history of music forms during the 17th and 18 th centuries, taking into account all these factors. This method introduces significant adjustments in the traditional practice of music form teaching in Russia, thereby bringing the understanding of students closer to the real processes that occurred in the music history of the 18th century.

  7. Interkulturelle kommunikative Kompetenz. Ein Versuch der Operationalisierung aus dem Fach Deutsch in der dänischen Lehrerausbildung

    DEFF Research Database (Denmark)

    Bjerre, Kirsten; Daryai-Hansen, Petra

    2017-01-01

    point of departure in Michael Byram’s model of intercultural communicative competence, which is compared with Darla K. Deardorff’s process model and with the definition given by the so-called REPT-project. Thereafter, an attempt is made to meet the above-mentioned requirement: on the basis...

  8. Improved liquid chromatography-MS/MS of heparan sulfate oligosaccharides via chip-based pulsed makeup flow.

    Science.gov (United States)

    Huang, Yu; Shi, Xiaofeng; Yu, Xiang; Leymarie, Nancy; Staples, Gregory O; Yin, Hongfeng; Killeen, Kevin; Zaia, Joseph

    2011-11-01

    Microfluidic chip-based hydrophilic interaction chromatography (HILIC) is a useful separation system for liquid chromatography-mass spectrometry (LC-MS) in compositional profiling of heparan sulfate (HS) oligosaccharides; however, ions observed using HILIC LC-MS are low in charge. Tandem MS of HS oligosaccharide ions with low charge results in undesirable losses of SO(3) from precursor ions during collision induced dissociation. One solution is to add metal cations to stabilize sulfate groups. Another is to add a nonvolatile, polar compound such as sulfolane, a molecule known to supercharge proteins, to produce a similar effect for oligosaccharides. We demonstrate use of a novel pulsed makeup flow (MUF) HPLC-chip. The chip enables controlled application of additives during specified chromatographic time windows and thus minimizes the extent to which nonvolatile additives build up in the ion source. The pulsed MUF system was applied to LC-MS/MS of HS oligosaccharides. Metal cations and sulfolane were tested as additives. The most promising results were obtained for sulfolane, for which supercharging of the oligosaccharide ions increased their signal strengths relative to controls. Tandem MS of these supercharged precursor ions showed decreased abundances of product ions from sulfate losses yet more abundant product ions from backbone cleavages.

  9. pyOpenMS: a Python-based interface to the OpenMS mass-spectrometry algorithm library.

    Science.gov (United States)

    Röst, Hannes L; Schmitt, Uwe; Aebersold, Ruedi; Malmström, Lars

    2014-01-01

    pyOpenMS is an open-source, Python-based interface to the C++ OpenMS library, providing facile access to a feature-rich, open-source algorithm library for MS-based proteomics analysis. It contains Python bindings that allow raw access to the data structures and algorithms implemented in OpenMS, specifically those for file access (mzXML, mzML, TraML, mzIdentML among others), basic signal processing (smoothing, filtering, de-isotoping, and peak-picking) and complex data analysis (including label-free, SILAC, iTRAQ, and SWATH analysis tools). pyOpenMS thus allows fast prototyping and efficient workflow development in a fully interactive manner (using the interactive Python interpreter) and is also ideally suited for researchers not proficient in C++. In addition, our code to wrap a complex C++ library is completely open-source, allowing other projects to create similar bindings with ease. The pyOpenMS framework is freely available at https://pypi.python.org/pypi/pyopenms while the autowrap tool to create Cython code automatically is available at https://pypi.python.org/pypi/autowrap (both released under the 3-clause BSD licence). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Sensitivity and proportionality assessment of metabolites from microdose to high dose in rats using LC-MS/MS.

    Science.gov (United States)

    Ni, Jinsong; Ouyang, Hui; Seto, Carmai; Sakuma, Takeo; Ellis, Robert; Rowe, Josh; Acheampong, Andrew; Welty, Devin; Szekely-Klepser, Gabriella

    2010-03-01

    The objective of this study was to evaluate the sensitivity requirement for LC-MS/MS as an analytical tool to characterize metabolites in plasma and urine at microdoses in rats and to investigate proportionality of metabolite exposure from a microdose of 1.67 µg/kg to a high dose of 5000 µg/kg for atorvastatin, ofloxacin, omeprazole and tamoxifen. Only the glucuronide metabolite of ofloxacin, the hydroxylation metabolite of omeprazole and the hydration metabolite of tamoxifen were characterized in rat plasma at microdose by LC-MS/MS. The exposure of detected metabolites of omeprazole and tamoxifen appeared to increase in a nonproportional manner with increasing doses. Exposure of ortho- and para-hydroxyatorvastatin, but not atorvastatin and lactone, increased proportionally with increasing doses. LC-MS/MS has demonstrated its usefulness for detecting and characterizing the major metabolites in plasma and urine at microdosing levels in rats. The exposure of metabolites at microdose could not simply be used to predict their exposure at higher doses.

  11. ICP-MS/MS-Based Ionomics: A Validated Methodology to Investigate the Biological Variability of the Human Ionome.

    Science.gov (United States)

    Konz, Tobias; Migliavacca, Eugenia; Dayon, Loïc; Bowman, Gene; Oikonomidi, Aikaterini; Popp, Julius; Rezzi, Serge

    2017-05-05

    We here describe the development, validation and application of a quantitative methodology for the simultaneous determination of 29 elements in human serum using state-of-the-art inductively coupled plasma triple quadrupole mass spectrometry (ICP-MS/MS). This new methodology offers high-throughput elemental profiling using simple dilution of minimal quantity of serum samples. We report the outcomes of the validation procedure including limits of detection/quantification, linearity of calibration curves, precision, recovery and measurement uncertainty. ICP-MS/MS-based ionomics was used to analyze human serum of 120 older adults. Following a metabolomic data mining approach, the generated ionome profiles were subjected to principal component analysis revealing gender and age-specific differences. The ionome of female individuals was marked by higher levels of calcium, phosphorus, copper and copper to zinc ratio, while iron concentration was lower with respect to male subjects. Age was associated with lower concentrations of zinc. These findings were complemented with additional readouts to interpret micronutrient status including ceruloplasmin, ferritin and inorganic phosphate. Our data supports a gender-specific compartmentalization of the ionome that may reflect different bone remodelling in female individuals. Our ICP-MS/MS methodology enriches the panel of validated "Omics" approaches to study molecular relationships between the exposome and the ionome in relation with nutrition and health.

  12. Data-independent MS/MS quantification of neuropeptides for determination of putative feeding-related neurohormones in microdialysate.

    Science.gov (United States)

    Schmerberg, Claire M; Liang, Zhidan; Li, Lingjun

    2015-01-21

    Food consumption is an important behavior that is regulated by an intricate array of neuropeptides (NPs). Although many feeding-related NPs have been identified in mammals, precise mechanisms are unclear and difficult to study in mammals, as current methods are not highly multiplexed and require extensive a priori knowledge about analytes. New advances in data-independent acquisition (DIA) MS/MS and the open-source quantification software Skyline have opened up the possibility to identify hundreds of compounds and quantify them from a single DIA MS/MS run. An untargeted DIA MS(E) quantification method using Skyline software for multiplexed, discovery-driven quantification was developed and found to produce linear calibration curves for peptides at physiologically relevant concentrations using a protein digest as internal standard. By using this method, preliminary relative quantification of the crab Cancer borealis neuropeptidome (winnowing candidate NPs related to a behavior of interest in a functionally relevant manner, and demonstrates the success of such a UPLC-MS(E) quantification method using the open source software Skyline.

  13. Sensitive quantification of apomorphine in human plasma using a LC-ESI-MS-MS method.

    Science.gov (United States)

    Abe, Emuri; Alvarez, Jean-Claude

    2006-06-01

    An analytical method based on liquid chromatography coupled with ion trap mass spectrometry (MS) detection with electrospray ionization interface has been developed for the identification and quantification of apomorphine in human plasma. Apomorphine was isolated from 0.5 mL of plasma using a liquid-liquid extraction with diethyl ether and boldine as internal standard, with satisfactory extraction recoveries. Analytes were separated on a 5-microm C18 Highpurity (Thermohypersil) column (150 mm x 2.1 mm I.D.) maintained at 30 degrees C, coupled to a precolumn (C18, 5-microm, 10 mm x 2.0 mm I.D., Thermo). The elution was achieved isocratically with a mobile phase of 2 mM NH4COOH buffer pH 3.8/acetonitrile (50/50, vol/vol) at a flow rate of 200 microL per minute. Data were collected either in full-scan MS mode at m/z 150 to 500 or in full-scan tandem mass spectrometry mode, selecting the [M+H]ion at m/z 268.0 for apomorphine and m/z 328.0 for boldine. The most intense daughter ion of apomorphine (m/z 237.1) and boldine (m/z 297.0) were used for quantification. Retention times were 2.03 and 2.11 minutes for boldine and apomorphine, respectively. Calibration curves were linear in the 0.025 to 20 ng/mL range. The limits of detection and quantification were 0.010 ng/mL and 0.025 ng/mL, respectively. Accuracy and precision of the assay were measured by analyzing 54 quality control samples for 3 days. At concentrations of 0.075, 1.5, and 15 ng/mL, intraday precisions were less than 10.1%, 5.3%, and 3.8%, and interday precisions were less than 4.8%, 6.6%, and 6.5%, respectively. Accuracies were in the 99.5 to 104.2% range. An example of a patient who was given 6 mg of apomorphine subcutaneously is shown, with concentrations of 14.1 ng/mL after 30 minutes and 0.20 ng/mL after 6 hours. The method described enables the unambiguous identification and quantification of apomorphine with very good sensitivity using only 0.5 mL of sample, and is very convenient for therapeutic drug

  14. Comparison of piracetam measured with HPLC-DAD, HPLC-ESI-MS, DIP-APCI-MS, and a newly developed and optimized DIP-ESI-MS.

    Science.gov (United States)

    Lenzen, Claudia; Winterfeld, Gottfried A; Schmitz, Oliver J

    2016-06-01

    The direct inlet probe-electrospray ionization (DIP-ESI) presented here was based on the direct inlet probe-atmospheric pressure chemical ionization (DIP-APCI) developed by our group. It was coupled to an ion trap mass spectrometer (MS) for the detection of more polar compounds such as degradation products from pharmaceuticals. First, the position of the ESI tip, the gas and solvent flow rates, as well as the gas temperature were optimized with the help of the statistic program Minitab® 17 and a caffeine standard. The ability to perform quantitative analyses was also tested by using different concentrations of caffeine and camphor. Calibration curves with a quadratic calibration regression of R (2) = 0.9997 and 0.9998 for caffeine and camphor, respectively, were obtained. The limit of detection of 2.5 and 1.7 ng per injection for caffeine and camphor were determined, respectively. Furthermore, a solution of piracetam was used to compare established analytical methods for this drug and its impurities such as HPLC-diode array detector (DAD) and HPLC-ESI-MS with the DIP-APCI and the developed DIP-ESI. With HPLC-DAD and 10 μg piracetam on column, no impurity could be detected. With HPLC-ESI-MS, two impurities (A and B) were identified with only 4.6 μg piracetam on column, while with DIP-ESI, an amount of 1.6 μg piracetam was sufficient. In the case of the DIP-ESI measurements, all detected impurities could be identified by MS/MS studies. Graphical Abstract Scheme of the DIP-ESI principle.

  15. Determination of piracetam in rat plasma by LC-MS/MS and its application to pharmacokinetics.

    Science.gov (United States)

    Wang, Xianqin; Zhu, Jiayin; Xu, Renai; Yang, Xuezhi; Wu, Haiya; Lin, Dan; Ye, Faqing; Hu, Lufeng

    2010-10-01

    A sensitive and selective liquid chromatography-tandem mass spectrometry method for the determination of piracetam in rat plasma was developed and validated over the concentration range of 0.1-20 µg/mL. After addition of oxiracetam as internal standard, a simplified protein precipitation with trichloroacetic acid (5%) was employed for the sample preparation. Chromatographic separation was performed by a Zorbax SB-Aq column (150 × 2.1 mm, 3.5 µm). The mobile phase was acetonitrile-1% formic acid in water (10:90 v/v) delivered at a flow rate of 0.3 mL/min. The MS data acquisition was accomplished in multiple reaction monitoring mode with a positive electrospray ionization interface. The lower limit of quantification was 0.1 µg/mL. For inter-day and intra-day tests, the precision (RSD) for the entire validation was less than 9%, and the accuracy was within the 94.6-103.2% range. The developed method was successfully applied to pharmacokinetic studies of piracetam in rats following single oral administration dose of 50 mg/kg. Copyright © 2010 John Wiley & Sons, Ltd.

  16. Matrix effects break the LC behavior rule for analytes in LC-MS/MS analysis of biological samples.

    Science.gov (United States)

    Fang, Nianbai; Yu, Shanggong; Ronis, Martin Jj; Badger, Thomas M

    2015-04-01

    High-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) are generally accepted as the preferred techniques for detecting and quantitating analytes of interest in biological matrices on the basis of the rule that one chemical compound yields one LC-peak with reliable retention time (Rt.). However, in the current study, we have found that under the same LC-MS conditions, the Rt. and shape of LC-peaks of bile acids in urine samples from animals fed dissimilar diets differed significantly among each other. To verify this matrix effect, 17 authentic bile acid standards were dissolved in pure methanol or in methanol containing extracts of urine from pigs consuming either breast milk or infant formula and analyzed by LC-MS/MS. The matrix components in urine from piglets fed formula significantly reduced the LC-peak Rt. and areas of bile acids. This is the first characterization of this matrix effect on Rt. in the literature. Moreover, the matrix effect resulted in an unexpected LC behavior: one single compound yielded two LC-peaks, which broke the rule of one LC-peak for one compound. The three bile acid standards which exhibited this unconventional LC behavior were chenodeoxycholic acid, deoxycholic acid, and glycocholic acid. One possible explanation for this effect is that some matrix components may have loosely bonded to analytes, which changed the time analytes were retained on a chromatography column and interfered with the ionization of analytes in the MS ion source to alter the peak area. This study indicates that a comprehensive understanding of matrix effects is needed towards improving the use of HPLC and LC-MS/MS techniques for qualitative and quantitative analyses of analytes in pharmacokinetics, proteomics/metabolomics, drug development, and sports drug testing, especially when LC-MS/MS data are analyzed by automation software where identification of an analyte is based on its exact molecular weight and Rt

  17. ICP-MS and elemental tags for the life sciences

    Energy Technology Data Exchange (ETDEWEB)

    Giesen, Charlotte

    2012-08-07

    Inductively coupled plasma mass spectrometry (ICP-MS) has been applied for the analysis of biomolecules due to its high sensitivity, wide linear dynamic range, and multielement capabilities. However, outside the elemental MS community the potential of this technique, e.g. for life sciences applications, is not yet fully exploited. Thus, the development of ICP-MS-based (immuno) assays for a wide range of medical (cancer diagnostics, cisplatin toxicity studies), biochemical (DNA microarray, single cell analysis), and environmental (analysis of comestible goods) applications was accomplished by utilization of chemical labels. Laser ablation (LA)-ICP-MS was employed for the direct analysis of solid samples like microarrays and thin tissue sections. An immunoassay was developed for ochratoxin A (OTA) determination in wine, and ICP-MS detection was compared to conventional photometry by gold nanoparticle tagging and horseradish peroxidase, respectively. Detection limits of the assay were optimized to 0.003 {mu}g L{sup -1}, and the quantification range was 0.01-1 {mu}g L{sup -1} for both methods. For LA-ICP-MS-based DNA microarray detection, gold nanoparticle tags were specifically introduced via a streptavidin-biotin linkage. In immunohistochemistry (IHC), up to 20 tumor markers are routinely evaluated for one patient and thus, a common analysis results in a series of time consuming staining procedures. Hence, LA-ICP-MS was elaborated as a detection tool for a novel, multiplexed IHC analysis of tissue sections. Different lanthanides were employed for the simultaneous detection of up to three tumor markers (Her 2, CK 7, and MUC 1) in a breast cancer tissue. Additionally, iodine was employed as a labeling reagent, and a new LA-ICP-MS method for single cell and cell nucleus imaging was developed at 4 {mu}m laser spot size. Iodine was also applied as a new internal standard for tissue samples. Moreover, Pt-protein complexes separated by an optimized 1D and 2D gel

  18. Large deep neural networks for MS lesion segmentation

    Science.gov (United States)

    Prieto, Juan C.; Cavallari, Michele; Palotai, Miklos; Morales Pinzon, Alfredo; Egorova, Svetlana; Styner, Martin; Guttmann, Charles R. G.

    2017-02-01

    Multiple sclerosis (MS) is a multi-factorial autoimmune disorder, characterized by spatial and temporal dissemination of brain lesions that are visible in T2-weighted and Proton Density (PD) MRI. Assessment of lesion burden and is useful for monitoring the course of the disease, and assessing correlates of clinical outcomes. Although there are established semi-automated methods to measure lesion volume, most of them require human interaction and editing, which are time consuming and limits the ability to analyze large sets of data with high accuracy. The primary objective of this work is to improve existing segmentation algorithms and accelerate the time consuming operation of identifying and validating MS lesions. In this paper, a Deep Neural Network for MS Lesion Segmentation is implemented. The MS lesion samples are extracted from the Partners Comprehensive Longitudinal Investigation of Multiple Sclerosis (CLIMB) study. A set of 900 subjects with T2, PD and a manually corrected label map images were used to train a Deep Neural Network and identify MS lesions. Initial tests using this network achieved a 90% accuracy rate. A secondary goal was to enable this data repository for big data analysis by using this algorithm to segment the remaining cases available in the CLIMB repository.

  19. Two-dimensional HPLC coupled to ICP-MS and electrospray ionisation (ESI)-MS/MS for investigating the bioavailability in vitro of arsenic species from edible seaweed

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Sartal, Cristina; Barciela-Alonso, Maria del Carmen; Bermejo-Barrera, Pilar [University of Santiago de Compostela, Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, Santiago de Compostela (Spain); Taebunpakul, Sutthinun [LGC Limited, Teddington, Middlesex (United Kingdom); Imperial College of Science, Technology and Medicine, South Kensington, Department of Materials, London (United Kingdom); National Institute of Metrology (Thailand), Pathumthani (Thailand); Stokes, Emma; Goenaga-Infante, Heidi [LGC Limited, Teddington, Middlesex (United Kingdom)

    2012-04-15

    Edible seaweed consumption is a route of exposure to arsenic. However, little attention has been paid to estimate the bioaccessibility and/or bioavailability of arsenosugars in edible seaweed and their possible degradation products during gastrointestinal digestion. This work presents first use of combined inductively coupled plasma mass spectroscopy (ICP-MS) with electrospray ionization tandem mass spectrometry (ESI-MS/MS) with two-dimensional HPLC (size exclusion followed by anion exchange) to compare the qualitative and quantitative arsenosugars speciation of different edible seaweed with that of their bioavailable fraction as obtained using an in vitro gastrointestinal digestion procedure. Optimal extraction conditions for As species from four seaweed namely kombu, wakame, nori and sea lettuce were selected as a compromise between As extraction efficiency and preservation of compound identity. For most investigated samples, the use of ammonium acetate buffer as extractant and 1 h sonication in a water bath followed by HPLC-ICP-MS resulted in 40-61% of the total As to be found in the buffered aqueous extract, of which 86-110% was present as arsenosugars (glycerol sugar, phosphate sugar and sulfonate sugar for wakame and kombu and glycerol sugar and phosphate sugar for nori). The exception was sea lettuce, for which the arsenosugar fraction (glycerol sugar, phosphate sugar) only comprised 44% of the total extracted As. Interestingly, the ratio of arsenobetaine and dimethylarsinic acid to arsenosugars in sea lettuce extracts seemed higher than that for the rest of investigated samples. After in vitro gastrointestinal digestion, approximately 11-16% of the total As in the solid sample was found in the dialyzates with arsenosugars comprising 93-120% and 41% of the dialyzable As fraction for kombu, wakame, nori and sea lettuce, respectively. Moreover, the relative As species distribution in seaweed-buffered extracts and dialyzates was found to be very similar

  20. Biodiesel production from microalgal isolates of southern Pakistan and quantification of FAMEs by GC-MS/MS analysis

    Directory of Open Access Journals (Sweden)

    Musharraf Syed

    2012-12-01

    Full Text Available Abstract Background Microalgae have attracted major interest as a sustainable source for biodiesel production on commercial scale. This paper describes the screening of six microalgal species, Scenedesmus quadricauda, Scenedesmus acuminatus, Nannochloropsis sp., Anabaena sp., Chlorella sp. and Oscillatoria sp., isolated from fresh and marine water resources of southern Pakistan for biodiesel production and the GC-MS/MS analysis of their fatty acid methyl esters (FAMEs. Results Growth rate, biomass productivity and oil content of each algal species have been investigated under autotrophic condition. Biodiesel was produced from algal oil by acid catalyzed transesterification reaction and resulting fatty acid methyl esters (FAMEs content was analyzed by GC/MS. Fatty acid profiling of the biodiesel, obtained from various microalgal oils showed high content of C-16:0, C-18:0, cis-Δ9C-18:1, cis-Δ11C-18:1 (except Scenedesmus quadricauda and 10-hydroxyoctadecanoic (except Scenedesmus acuminatus. Absolute amount of C-14:0, C-16:0 and C-18:0 by a validated GC-MS/MS method were found to be 1.5-1.7, 15.0-42.5 and 4.2-18.4 mg/g, respectively, in biodiesel obtained from various microalgal oils. Biodiesel was also characterized in terms of cetane number, kinematic viscosity, density and higher heating value and compared with the standard values. Conclusion Six microalgae of local origin were screened for biodiesel production. A method for absolute quantification of three important saturated fatty acid methyl esters (C-14, C-16 and C-18 by gas chromatography-tandem mass spectrometry (GC-MS/MS, using multiple reactions monitoring (MRM mode, was employed for the identification and quantification of biodiesels obtained from various microalgal oils. The results suggested that locally found microalgae can be sustainably harvested for the production of biodiesel. This offers the tremendous economic opportunity for an energy-deficient nation.

  1. A sensitive LC-MS/MS method for measurement of organophosphorus pesticides and their oxygen analogs in air sampling matrices.

    Science.gov (United States)

    Armstrong, Jenna L; Dills, Russell L; Yu, Jianbo; Yost, Michael G; Fenske, Richard A

    2014-01-01

    A rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for determination of levels of the organophosphorus (OP) pesticides chlorpyrifos (CPF), azinphos methyl (AZM), and their oxygen analogs chlorpyrifos-oxon (CPF-O) and azinphos methyl-oxon (AZM-O) on common active air sampling matrices. XAD-2 resin and polyurethane foam (PUF) matrices were extracted with acetonitrile containing stable-isotope labeled internal standards (ISTD). Analysis was accomplished in Multiple Reaction Monitoring (MRM) mode, and analytes in unknown samples were identified by retention time (±0.1 min) and qualifier ratio (±30% absolute) as compared to the mean of calibrants. For all compounds, calibration linearity correlation coefficients were ≥0.996. Limits of detection (LOD) ranged from 0.15-1.1 ng/sample for CPF, CPF-O, AZM, and AZM-O on active sampling matrices. Spiked fortification recoveries were 78-113% from XAD-2 active air sampling tubes and 71-108% from PUF active air sampling tubes. Storage stability tests also yielded recoveries ranging from 74-94% after time periods ranging from 2-10 months. The results demonstrate that LC-MS/MS is a sensitive method for determining these compounds from two different matrices at the low concentrations that can result from spray drift and long range transport in non-target areas following agricultural applications. In an inter-laboratory comparison, the limit of quantification (LOQ) for LC-MS/MS was 100 times lower than a typical gas chromatography-mass spectrometry (GC-MS) method.

  2. Integrated Solid-Phase Extraction-Capillary Liquid Chromatography (speLC) Interfaced to ESI-MS/MS for Fast Characterization and Quantification of Protein and Proteomes

    DEFF Research Database (Denmark)

    Falkenby, Lasse Gaarde; Such-Sanmartín, Gerard; Larsen, Martin Røssel

    2014-01-01

    min speLC-MS/MS experiment. Analysis by selected reaction monitoring by speLC-SRM-MS/MS of distinct peptides derived from the blood proteins IGF1, IGF2, IBP2, and IBP3 demonstrated protein quantification with CV values below 10% across 96 replicates. The speLC-MS/MS system is ideally suited for fast......The high peptide sequencing speed provided by modern hybrid tandem mass spectrometers enables the utilization of fast liquid chromatographic (LC) separation techniques. We present a robust solid-phase extraction/capillary LC system (speLC) for 5-10 min separation of semicomplex peptide mixtures...

  3. LC-MS/MS method for the determination of clodronate in human plasma.

    Science.gov (United States)

    Hasan, Mahmoud; Schumacher, Gitta; Seekamp, Anne; Taedken, Tobias; Siegmund, Werner; Oswald, Stefan

    2014-11-01

    Clodronate belongs to the class of bisphosphonates which are used for the treatment of bone disorders. Due to its high polarity it has a low and highly variable oral bioavailability which results in low plasma concentrations and requires sensitive bioanalytical methods to characterize its pharmacokinetics in human. Here, we describe for the first time the development and validation of a LC-MS/MS assay for the quantification of clodronate in human plasma. The bisphosphonate was isolated from the biological matrix by protein precipitation using perchloric acid (10%), and derivatized with trimethylorthoacetate prior sample clean-up with liquid-liquid extraction using methyl tert-butyl ether. The chromatography was performed using an isocratic elution with ammonium acetate 5mM (85% v/v, pH 3.8) and acetonitrile (15% v/v) as mobile phase with a flow rate of 300μl/min on a reversed-phase column (Supelco Ascentis(®), C18) temporized at 50°C. The mass spectrometric detection was done using the API4000 triple quadruple mass spectrometer monitoring the mass/charge transitions 301.0/145 for clodronate and 305.2/137.1 for the internal standard etidronate. The analytical range was set to 5-800ng/ml, allowing an evaluation of the plasma concentration-time profiles of clodronate for approximately 7-8 half-life (∼24h). The method was validated according to current FDA/EMA guidelines on bioanalytical method validation with respect to specificity, linearity, intra- and inter-day accuracy and precision, matrix effect, recovery as well as stability. The precision of the assay was 0.6-6.9% and 0.6-8.1% for the intra-day and inter-day variability, respectively. The intra-day and inter-day accuracy (error) was 0.6-8.8% and 2.2-4.5%. The recovery of the analyte was low (2-3%) but reproducible over the entire validation range and sufficient to monitor the target concentrations in human plasma. The drug was shown to be stable in plasma at room temperature for at least 3h (96.0±6%) and

  4. Global metabolic profiling procedures for urine using UPLC-MS.

    Science.gov (United States)

    Want, Elizabeth J; Wilson, Ian D; Gika, Helen; Theodoridis, Georgios; Plumb, Robert S; Shockcor, John; Holmes, Elaine; Nicholson, Jeremy K

    2010-06-01

    The production of 'global' metabolite profiles involves measuring low molecular-weight metabolites (sample preparation, stability/storage and the selection of chromatographic conditions that balance metabolome coverage, chromatographic resolution and throughput. We discuss quality control and metabolite identification, as well as provide details of multivariate data analysis approaches for analyzing such MS data. Using this protocol, the analysis of a sample set in 96-well plate format, would take ca. 30 h, including 1 h for system setup, 1-2 h for sample preparation, 24 h for UPLC-MS analysis and 1-2 h for initial data processing. The use of UPLC-MS for metabolic profiling in this way is not faster than the conventional HPLC-based methods but, because of improved chromatographic performance, provides superior metabolome coverage.

  5. Can LC and LC-MS ever replace immunoassays?

    Directory of Open Access Journals (Sweden)

    Timothy G. Cross

    2016-10-01

    Full Text Available Immunoassays have been the technology of choice for the analysis of biomolecules for many decades across a wide range of applications in research, diagnostics and infectious disease monitoring. There are good reasons for the wide adoption of immunoassays but even such a well established and characterised technique has limitations and as such investigators are looking at alternative technologies. One such alternative is liquid chromatography (LC and, more specifically, liquid chromatography coupled with mass spectrometry (LC-MS. This article will review both immunoassay and LC and LC-MS technologies and methodologies and discuss the advantages and limitations of both approaches. In addition, the next developments that will need to occur before there is widespread adoption of LC and LC-MS technology preferentially over immunoassays will be examined.

  6. Applications of ICP-MS in marine analytical chemistry

    Energy Technology Data Exchange (ETDEWEB)

    McLaren, J W; Siu, K W.M.; Lam, J W; Willie, S N; Maxwell, P S; Palepu, A; Koether, M; Berman, S S [National Research Council of Canada, Ottawa, ON (Canada). Analytical Chemistry Section

    1990-07-01

    The versatility of ICP-MS in marine analytical chemistry is illustrated with applications to the multielement trace analysis of two recently released marine reference materials, the coastal seawater CASS-2 and the non-defatted lobster hepatopancreas tissue LUTS-1, and to the determination of tributyltin and dibutyltin in the harbour sediment reference material PACS-1 by HPLC-ICP-MS. Seawater analyses were performed after separation of the trace elements either by adsorption on immobilized 8-hydroxyquinoline or by reductive coprecipitation with iron and palladium. Simultaneous determination of seven trace elements in LUTS-1, including mercury, by isotope dilution ICP-MS, was achieved after dissolution by microwave digestion with nitric acid and hydrogen peroxide. Butyltin species in PACS-1 were separated by cation exchange HPLC of an extract of the sediment; method detection limits for tributyltin and dibutyltin in sediment samples are estimated to be 5 ng Sn/g and 12 ng Sn/g, respectively. (orig.).

  7. [Applications of MALDI-TOF-MS in clinical microbiology laboratory].

    Science.gov (United States)

    Carbonnelle, Etienne; Nassif, Xavier

    2011-10-01

    For twenty years, mass spectrometry (MS) has emerged as a particularly powerful tool for analysis and characterization of proteins in research. It is only recently that this technology, especially MALDI-TOF-MS (Matrix Assisted Laser Desorption Ionization Time-Of-Flight) has entered the field of routine microbiology. This method has proven to be reliable and safe for the identification of bacteria, yeasts, filamentous fungi and dermatophytes. MALDI-TOF-MS is a rapid, precise and cost-effective method for identification, compared to conventional phenotypic techniques or molecular biology. Its ability to analyse whole microorganisms with few sample preparation has greatly reduced the time to identification (1-2 min). Furthermore, this technology can be used to identify bacteria directly from clinical samples as blood culture bottles or urines. Future applications will be developed in order to provide direct information concerning virulence or resistance protein markers. © 2011 médecine/sciences – Inserm / SRMS.

  8. MALDI-TOF MS in the Microbiology Laboratory: Current Trends.

    Science.gov (United States)

    Schubert, Sören; Kostrzewa, Markus

    2017-01-01

    Within less than a decade matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become a gold standard for microbial identification in clinical microbiology laboratories. Besides identification of microorganisms the typing of single strains as well as the antibiotic and antimycotic resistance testing has come into focus in order to speed up the microbiological diagnostic. However, the full potential of MALDI-TOF MS has not been tapped yet and future technological advancements will certainly expedite this method towards novel applications and enhancement of current practice. So, the following chapter shall be rather a brainstorming and forecast of how MALDI-TOF MS will develop to influence clinical diagnostics and microbial research in the future. It shall open up the stage for further discussions and does not claim for overall validity.

  9. Analysis of nanoparticles using the ICAP Q ICP-MS

    DEFF Research Database (Denmark)

    Kutscher, Daniel; McSheehy-Ducos, Shona; Lindemann, Torsten

    2014-01-01

    The analysis of Nanoparticles (NPs) has become one of the hot topics in analytical chemistry. However, detailed knowledge about potential risks or hazards is still unavailable. Two approaches have been developed in recent years using ICP-MS as a detection system: hyphenation of an appropriate...... separation technique like Field-Flow-Fractionation (FFF), or direct analysis using spICP-MS. The separation of particles and particle mixtures using FFF is based on the differing mobilities of different particle sizes in a laminar liquid flow. FFF is compatible for particle sizes in the low nm to low μm...... range and is thus perfectly suited for the separation of different NPs. Combined with other detection systems such as dynamic light scattering, it can provide also additional information about the particles of interest, like shape. In comparison, spICP-MS is able to analyze NPs directly based...

  10. ICP-MS analysis for long-lived radionuclides

    International Nuclear Information System (INIS)

    Roos, P.

    2010-01-01

    Full text: Inductively coupled plasma mass spectrometry (ICP-MS) is an attractive alternative for the analysis of radioisotopes having a half-life in the order of several hundred years and above. The technique should not be considered a replacement for radiometric measurements of these isotopes but merely an alternative. Similarly to radiometric techniques like alpha and beta spectrometry most analysis of 'low-level' concentrations by ICP-MS requires chemical isolation of the element in question. For 'ultra-low-level' concentrations this clean-up of the sample is usually even more necessary than for the alternative radiometric techniques. The presentation gives an overview of advantages and disadvantages in using ICP-MS and compares it to relevant radiometric alternatives. (author)

  11. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) based bioavailability determination of the major classes of phytochemicals.

    Science.gov (United States)

    Stylos, Evgenios; Chatziathanasiadou, Maria V; Syriopoulou, Aggeliki; Tzakos, Andreas G

    2017-03-15

    Natural products derived from plants have served as an inexhausted source for drug discovery and drug development. They have been evolutionary amplified with drug-like properties and have already illustrated immense therapeutic potential over an array of different diseases. However, their incorporation in the drug discovery pipeline has been diminished the last two decades. This was probably due to barriers related to their inherent difficulties to be integrated in high-throughput screening assays as also their largely unexplored bioavailability. Analytical procedures have come into the spotlight, a result of the continuous development of the instrumentation's capabilities as far as detection and separation is concerned. Integral part of this technological evolution is LC-MS instrumentation and its extended use for the determination of various compounds. The fact that it provides extra sensitivity, specificity and good separation in complex samples, makes LC-MS/MS the ultimate tool in the determination of many types of chemical compounds, such as phytochemicals. Herein, we focus on the achievements of the last five years in quantitative analysis of the major classes of phytochemicals (flavonoids, alkaloids, terpenes, glycosides and saponins) in plasma, through LC-MS/MS, as also their bioavailability. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. [Separation and identification of red pigments in natural red yolk of duck's eggs by HPLC-MS-MS].

    Science.gov (United States)

    Liu, Liangzhong; Zhang, Min; Peng, Guanghua; Wang, Haibin; Zhang, Shenghua

    2004-05-01

    The natural red yolk of duck's eggs is produced by the laying duck in the lake areas in southward of China. In the laying duck breeding areas such as Honghu, Jianli, Xiantao, Tianmen and Hanchuan citys in Hubei Province, the culturists are used to feeding fresh pondweeds to the laying ducks. The yolk of duck's eggs is natural red with the chrominance reaching up to and/or above RCF (Roche Yolk Color Fan) 15. The red pigment components of natural red yolk of duck's eggs were separated and identified by thin layer chromatography (TLC), high performance liquid chromatography-mass spectrometry-mass spectrometry (HPLC-MS-MS) and high resolution electron impact-mass spectrometry (EI-MS). Four isomers of red pigments were separated by HPLC on a RP-C18 column with methanol-water (99.5:0.5, v/v) as mobile phase. The lambda(max) of the four components were 482, 488, 496, 501 nm, respectively, and all of them were single peak on chromatogram. They had the same molecular mass (Mr = 562), and had the same fragment peaks of MS2 with rhodoxanthin. The molecular formula of red pigments was determined as C40H50O2 by high resolution EI-MS. The results indicate that the red pigment is rhodoxanthin, and they are all cis-isomers of rhodoxanthin.

  13. Evaluation of laser diode thermal desorption-tandem mass spectrometry (LDTD-MS-MS) in forensic toxicology.

    Science.gov (United States)

    Bynum, Nichole D; Moore, Katherine N; Grabenauer, Megan

    2014-10-01

    Many forensic laboratories experience backlogs due to increased drug-related cases. Laser diode thermal desorption (LDTD) has demonstrated its applicability in other scientific areas by providing data comparable with instrumentation, such as liquid chromatography-tandem mass spectrometry, in less time. LDTD-MS-MS was used to validate 48 compounds in drug-free human urine and blood for screening or quantitative analysis. Carryover, interference, limit of detection, limit of quantitation, matrix effect, linearity, precision and accuracy and stability were evaluated. Quantitative analysis indicated that LDTD-MS-MS produced precise and accurate results with the average overall within-run precision in urine and blood represented by a %CV forensic toxicology but before it can be successfully implemented that there are some challenges that must be addressed. Although the advantages of the LDTD system include minimal maintenance and rapid analysis (∼10 s per sample) which makes it ideal for high-throughput forensic laboratories, a major disadvantage is its inability or difficulty analyzing isomers and isobars due to the lack of chromatography without the use of high-resolution MS; therefore, it would be best implemented as a screening technique. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. A LC-MS-MS method for determination of low doxazosin concentrations in plasma after oral administration to dogs.

    Science.gov (United States)

    Erceg, Marijana; Cindric, Mario; Pozaic Frketic, Lidija; Vertzoni, Maria; Cetina-Cizmek, Biserka; Reppas, Christos

    2010-02-01

    A rapid and sensitive reversed phase liquid chromatography- tandem mass spectrometry (LC-MS-MS) method is developed for the determination of doxazosin in canine plasma. The samples are prepared by precipitation of proteins using a mixture of methanol and acetonitrile, followed by freezing and evaporation of the organic solvent. The remaining dry residue is redissolved in mobile phase and analyzed by LC-MS-MS with positive electrospray ionization using the selected reactions monitoring mode. An XTerra MS C(18) column, a mobile phase composed of acetonitrile and 2mM ammonium acetate with gradient elution, and a flow rate of 400 microL/min are employed. The elution times for prazosin (internal standard) and doxazosin are approximately 8 and 10 min, respectively. Calibration curves are linear in the 1-20 ng/mL concentration range. Limits of detection and quantification are 0.4 ng/mL and 1.2 ng/mL, respectively. Recovery is higher than 94%. Intra- and inter-day relative standard deviations are below 7% and 8%, respectively. The method is applied for the determination of doxazosin plasma levels following a single administration of doxazosin base and doxazosin mesylate tablets (2 mg dose) to dogs in the fed state. The results indicate possible superiority of the mesylate salt on the plasma input rates of doxazosin.

  15. PCI-GC-MS-MS approach for identification of non-amino organic acid and amino acid profiles.

    Science.gov (United States)

    Luan, Hemi; Yang, Lin; Ji, Fenfen; Cai, Zongwei

    2017-03-15

    Alkyl chloroformate have been wildly used for the fast derivatization of metabolites with amino and/or carboxyl groups, coupling of powerful separation and detection systems, such as GC-MS, which allows the comprehensive analysis of non-amino organic acids and amino acids. The reagents involving n-alkyl chloroformate and n-alcohol are generally employed for providing symmetric labeling terminal alkyl chain with the same length. Here, we developed an asymmetric labeling strategy and positive chemical ionization gas chromatography-tandem mass spectrometry (PCI-GC-MS-MS) approach for determination of non-amino organic acids and amino acids, as well as the short chain fatty acids. Carboxylic and amino groups could be selectively labelled by propyl and ethyl groups, respectively. The specific neutral loss of C 3 H 8 O (60Da), C 3 H 5 O 2 (74Da) and C 4 H 8 O 2 (88Da) were useful in the selective identification for qualitative analysis of organic acids and amino acid derivatives. PCI-GC-MS-MS using multiple reaction monitoring (MRM) was applied for semi-quantification of typical non-amino organic acids and amino acids. This method exhibited a wide range of linear range, good regression coefficient (R 2 ) and repeatability. The relative standard deviation (RSD) of targeted metabolites showed excellent intra- and inter-day precision (chloroformate derivatization. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. A comparison of the determination and speciation of inorganic arsenic using general HPLC methodology with UV, MS and MS/MS detection.

    Science.gov (United States)

    Gilmartin, Gregory; Gingrich, Diane

    2018-04-15

    The determination and speciation of arsenic in natural resources such as drinking water and agricultural soils has been a growing concern in recent years due to its many toxicological effects [1-3]. To speciate and quantitate concentrations of arsenic, typically an ion chromatograph (IC) interfaced to an inductively coupled plasma mass spectrometer (ICP-MS) is employed [4-9]. This methodology may be very robust and sensitive, but it is expensive and not as ubiquitous as high performance liquid chromatography (HPLC) with ultraviolet (UV) absorbance detection or electrospray ionization mass spectrometry (ESI-MS). Anion exchange chromatography is a well-documented means of speciating arsenite (As(III), As 2 O 3 ) and arsenate (As(V), AsO 4 ) using UV [10], conductivity [11], or ESI-MS detection [12,13]. This paper demonstrates the utilization of common liquid chromatographic instrumentation to speciate and determines inorganic Arsenic compounds using UV or MS via selected ion recording (SIR) or multiple reaction monitoring (MRM) detection. This paper describes the analysis of arsenite and arsenate samples prepared using both deionized and ground water. The limit of quantitation for the techniques described in this paper for samples spiked in ground water were 454 ppb (As(III)) and 562 ppb (As(V)) for UV detection, 45.4 ppb (As(III)) and 56.2 ppb (As(V)) for SIR detection, and 4.54 ppb (As(III)) and 5.62 ppb (As(V)) for MRM detection. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Brain Functional Connectivity in MS: An EEG-NIRS Study

    Science.gov (United States)

    2015-10-01

    1 AWARD NUMBER: W81XWH-14-1-0582 TITLE: Brain Functional Connectivity in MS: An EEG -NIRS Study PRINCIPAL INVESTIGATOR: Heather Wishart...Functional Connectivity in MS: An EEG -NIRS Study 5b. GRANT NUMBER W81XWH-14-1-0582 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Heather...electrical ( EEG ) and blood volume and blood oxygen-based (NIRS and fMRI) signals, and to use the results to help optimize blood oxygen level

  18. Influence map baserad Ms. Pac-Man och Ghost Kontroller

    OpenAIRE

    Svensson, Johan

    2012-01-01

    This thesis will cover the use oftheinfluence map technique applied to the retro game Ms. Pac-Man. A game thatis easy to learn but hard to master. The Ms. Pac-Man controller is implemented with five main parameters that alters the behaviour of the controller while the Ghost controller have three parameters. The experimental results of the controllers is explored to using the alterations of the parameters to find its peak of performance. The conclusion from using the influence map for this gam...

  19. A Liquid Chromatography-Quadrupole-Time of Flight Mass Spectrometry (LC-Q-TOF MS) Study for Analyzing 35 Corticosteroid Compounds: Elucidation of MS/MS Fragmentation Pathways

    International Nuclear Information System (INIS)

    Noh, Eunyoung; Yoon, Chang-Yong; Lee, Ji Hyun; Baek, Sun-Young; Do, Jung-Ah; Lee, Jung-min; Oh, Han Bin

    2016-01-01

    Corticosteroids have been often found to be added to a dietary supplement for the purpose of illegally improving the effect of their products. Thus, it is imperative to develop or improve a method that enables one to rapidly and reliably analyze corticosteroids in health or dietary supplements, for the safety management purpose. In the present study, results from liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) experiments for the selected 35 corticosteroid compounds are presented, which can be useful for the qualitative screening of corticosteroids in health or dietary supplements. Specifically, retention times, accurate mass data of the protonated steroids, m/z values of major fragment ions are given for the 35 corticosteroids. Further, fragmentation pathways for the selected steroids are also suggested. Based on the suggested fragmentation pathways, it was shown that an unknown steroid compound can be readily identified using the knowledge of a group of unique and specific common skeletal fragments. The high selectivity and sensitivity of the LC-Q-TOF-MS/MS results combined with the knowledge of the fragmentation pathways can offer a new opportunity for rapid and accurate screening of corticosteroids, thus preventing health-related incidents involving adulterated products and clamping down on illegally circulated health products.

  20. Multiresidue method for pesticide residue analysis in food of animal and plant origin based on GC or LC and MS or MS/MS.

    Science.gov (United States)

    Muñoz, Eva; Muñoz, Gloria; Pineda, Laura; Serrahima, Eulalia; Centrich, Francesc

    2012-01-01

    A multiresidue method based on GC or LC and MS or MS/MS for the determination of 204 pesticides in diverse food matrixes of animal and plant origin is described. The method can include different stages of cleanup according to the chemical characteristics of each sample. Samples were extracted using accelerated solvent extraction. Those with a high fat content or that contained chlorophyll required further purification by gel permeation chromatography and/or SPE (ENVI-Carb). The methodology developed here was fully validated; the LOQs for the 204 pesticides are presented. The LOQ values lie between 0.01 to 0.02 mg/kg. However, in some cases, mainly in baby food, they were as low as 0.003 mg/kg, thereby meeting European Union requirements on maximum residue levels for pesticides, as outlined in European regulation 396/2005 and the Commission Directive 2003/13/EC. The procedure has been accredited for a wide scope of pesticides and matrixes by the Spanish Accreditation Body (ENAC) following ISO/IEC 17025:2005, as outlined in ENAC technical note NT-19.

  1. A Liquid Chromatography-Quadrupole-Time of Flight Mass Spectrometry (LC-Q-TOF MS) Study for Analyzing 35 Corticosteroid Compounds: Elucidation of MS/MS Fragmentation Pathways

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Eunyoung; Yoon, Chang-Yong; Lee, Ji Hyun; Baek, Sun-Young; Do, Jung-Ah [Ministry of Food and Drug Safety, Cheongju (Korea, Republic of); Lee, Jung-min; Oh, Han Bin [Sogang University, Seoul (Korea, Republic of)

    2016-07-15

    Corticosteroids have been often found to be added to a dietary supplement for the purpose of illegally improving the effect of their products. Thus, it is imperative to develop or improve a method that enables one to rapidly and reliably analyze corticosteroids in health or dietary supplements, for the safety management purpose. In the present study, results from liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) experiments for the selected 35 corticosteroid compounds are presented, which can be useful for the qualitative screening of corticosteroids in health or dietary supplements. Specifically, retention times, accurate mass data of the protonated steroids, m/z values of major fragment ions are given for the 35 corticosteroids. Further, fragmentation pathways for the selected steroids are also suggested. Based on the suggested fragmentation pathways, it was shown that an unknown steroid compound can be readily identified using the knowledge of a group of unique and specific common skeletal fragments. The high selectivity and sensitivity of the LC-Q-TOF-MS/MS results combined with the knowledge of the fragmentation pathways can offer a new opportunity for rapid and accurate screening of corticosteroids, thus preventing health-related incidents involving adulterated products and clamping down on illegally circulated health products.

  2. Characterization of Proteins Present in Isolated Senile Plaques from Alzheimer's Diseased Brains by MALDI-TOF MS with MS/MS.

    Science.gov (United States)

    Kelley, Andrea R; Perry, George; Bach, Stephan B H

    2018-04-18

    The increase of insoluble senile plaques in the brain is a primary hallmark of Alzheimer's disease. The usefulness of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) with tandem MS for the characterization of senile plaques from AD brains and the relevance of the components identified to furthering AD research using MS is discussed. Thirty-three components were reproducibly observed within tryptic aliquots of senile plaques from two different AD brains after sample preparation optimization. Additionally, this is one of the first accounts of LIFT being utilized for the direct sequencing of peptides from isolated senile plaques. While many of the species observed coisolated within senile plaques have been linked to AD etiology, if only speculatively, this is the first instance that many of them have been demonstrated to be a part of the plaques themselves. This work is the first step in determining the potential roles that the species may have in the aggregation or proliferation of the plaques.

  3. Wavelet-based peak detection and a new charge inference procedure for MS/MS implemented in ProteoWizard's msConvert.

    Science.gov (United States)

    French, William R; Zimmerman, Lisa J; Schilling, Birgit; Gibson, Bradford W; Miller, Christine A; Townsend, R Reid; Sherrod, Stacy D; Goodwin, Cody R; McLean, John A; Tabb, David L

    2015-02-06

    We report the implementation of high-quality signal processing algorithms into ProteoWizard, an efficient, open-source software package designed for analyzing proteomics tandem mass spectrometry data. Specifically, a new wavelet-based peak-picker (CantWaiT) and a precursor charge determination algorithm (Turbocharger) have been implemented. These additions into ProteoWizard provide universal tools that are independent of vendor platform for tandem mass spectrometry analyses and have particular utility for intralaboratory studies requiring the advantages of different platforms convergent on a particular workflow or for interlaboratory investigations spanning multiple platforms. We compared results from these tools to those obtained using vendor and commercial software, finding that in all cases our algorithms resulted in a comparable number of identified peptides for simple and complex samples measured on Waters, Agilent, and AB SCIEX quadrupole time-of-flight and Thermo Q-Exactive mass spectrometers. The mass accuracy of matched precursor ions also compared favorably with vendor and commercial tools. Additionally, typical analysis runtimes (∼1-100 ms per MS/MS spectrum) were short enough to enable the practical use of these high-quality signal processing tools for large clinical and research data sets.

  4. Wavelet-Based Peak Detection and a New Charge Inference Procedure for MS/MS Implemented in ProteoWizard’s msConvert

    Science.gov (United States)

    2015-01-01

    We report the implementation of high-quality signal processing algorithms into ProteoWizard, an efficient, open-source software package designed for analyzing proteomics tandem mass spectrometry data. Specifically, a new wavelet-based peak-picker (CantWaiT) and a precursor charge determination algorithm (Turbocharger) have been implemented. These additions into ProteoWizard provide universal tools that are independent of vendor platform for tandem mass spectrometry analyses and have particular utility for intralaboratory studies requiring the advantages of different platforms convergent on a particular workflow or for interlaboratory investigations spanning multiple platforms. We compared results from these tools to those obtained using vendor and commercial software, finding that in all cases our algorithms resulted in a comparable number of identified peptides for simple and complex samples measured on Waters, Agilent, and AB SCIEX quadrupole time-of-flight and Thermo Q-Exactive mass spectrometers. The mass accuracy of matched precursor ions also compared favorably with vendor and commercial tools. Additionally, typical analysis runtimes (∼1–100 ms per MS/MS spectrum) were short enough to enable the practical use of these high-quality signal processing tools for large clinical and research data sets. PMID:25411686

  5. ESI(+-MS and GC-MS Study of the Hydrolysis of N-Azobenzyl Derivatives of Chitosan

    Directory of Open Access Journals (Sweden)

    Fernanda S. Pereira

    2014-10-01

    Full Text Available New N-p-chloro-, N-p-bromo-, and N-p-nitrophenylazobenzylchitosan derivatives, as well as the corresponding azophenyl and azophenyl-p-sulfonic acids, were synthesized by coupling N-benzylvchitosan with aryl diazonium salts. The synthesized molecules were analyzed by UV-Vis, FT-IR, 1H-NMR and 15N-NMR spectroscopy. The capacity of copper chelation by these materials was studied by AAS. Chitosan and the derivatives were subjected to hydrolysis and the products were analyzed by ESI(+-MS and GC-MS, confirming the formation of N-benzyl chitosan. Furthermore, the MS results indicate that a nucleophilic aromatic substitution (SnAr reaction occurs under hydrolysis conditions, yielding chloroaniline from N-p-bromo-, and N-p-nitrophenylazo-benzylchitosan as well as bromoaniline from N-p-chloro-, and N-p-nitrophenylazobenzyl-chitosan.

  6. Determination of rhenium traces in river water by Q-ICP-MS and HR-ICP-MS

    International Nuclear Information System (INIS)

    Uchida, S.; Tagami, K.; Saito, M.

    2003-01-01

    A simple separation method was applied to determine rhenium in river water using Q-ICP-MS and HR-ICP-MS. Re was concentrated from 420-925 ml river water using a TEVA resin minicolumn. Such extraction using a resin could separate Re from most sample matrices and trace elements. Almost 100% recovery was found throughout the method as determined with radioactive multitracers. The HR-ICP-MS was also used for the direct determination because of its low detection limit for Re (0.007 pg/ml). The Re concentration in the river water samples ranged from 0.9 to 6.5 pg/ml and the three analysis results showed good agreement with each other. (author)

  7. Analysis of a Brazilian green propolis from Baccharis dracunculifolia by HPLC-APCI-MS and GC-MS

    Directory of Open Access Journals (Sweden)

    Roberto Chang

    Full Text Available Ethanol and dichloromethane extracts of a Brazilian green propolis from Baccharis dracunculifolia were analyzed by HPLC-APCI-MS and GC-MS, respectively. The HPLC-APCI-MS technique, at the positive mode, furnished a complete and unequivocal chemical composition of the green propolis sample. It serves as fingerprint for different propolis samples. The composition of the ethanol extract consisted mainly of cinnamic acid and derivatives, flavonoids, benzoic acid and a few benzoates, non-hydroxylated aromatics, and aliphatic acids and esters, which are normally not reported in the literature because they do not absorb UV light. The main constituents of the dichloromethane extract were prenylated compounds, alkanes and terpenoids.

  8. Determination of carbohydrates in medicinal plants--comparison between TLC, mf-MELDI-MS and GC-MS.

    Science.gov (United States)

    Qureshi, Muhammad Nasimullah; Stecher, Guenther; Sultana, Tahira; Abel, Gudrun; Popp, Michael; Bonn, Guenther K

    2011-01-01

    Quality control in the pharmaceutical and phytopharmaceutical industries requires fast and reliable methods for the analysis of raw materials and final products. This study evaluates different analytical approaches in order to recognise the most suitable technique for the analysis of carbohydrates in herbal drug preparations. The specific focus of the study is on thin-layer chromatography (TLC), gas chromatography (GC), and a newly developed mass spectrometric method, i.e. matrix free material enhanced laser desorption/ionisation time of flight mass spectrometry (mf-MELDI-MS). Samples employed in the study were standards and microwave-assisted water extracts from Quercus. TLC analysis proved the presence of mono-, di- and trisaccharides within the biological sample and hinted at the existence of an unknown carbohydrate of higher oligomerisation degree. After evaluation of different derivatisation techniques, GC-MS confirmed data obtained via TLC for mono- to trisaccharides, delivering additionally quantified values under a considerable amount of time. A carbohydrate of higher oligomerisation degree could not be found. The application of mf-MELDI-MS further confirmed the presence of carbohydrates up to trisaccharides, also hinting at the presence of a form of tetrasaccharide. Besides this information, mf-MELDI-MS delivered further data about other substances present in the extract. Quantitative determination resulted in 1.750, 1.736 and 0.336 mg/mL for glucose, sucrose and raffinose respectively. Evaluation of all three techniques employed, clearly proved the heightened performance of mf-MELDI-MS for the qualitative analysis of complex mixtures, as targets do not need modification and analysis requires only a few minutes. In addition, GC-MS is suitable for quantitative analysis. Copyright © 2011 John Wiley & Sons, Ltd.

  9. UPLC-MS/MS based diagnostics for epithelial ovarian cancer using fully sialylated C4-binding protein.

    Science.gov (United States)

    Tanabe, Kazuhiro; Matsuo, Koji; Miyazawa, Masaki; Hayashi, Masaru; Ikeda, Masae; Shida, Masako; Hirasawa, Takeshi; Sho, Ryuichiro; Mikami, Mikio

    2018-05-01

    Serum levels of fully sialylated C4-binding protein (FS-C4BP) are remarkably elevated in patients with epithelial ovarian cancer (EOC) and can be used as a marker to distinguish ovarian clear cell carcinoma from endometrioma. This study aimed to develop a stable, robust and reliable liquid chromatography-hybrid mass spectrometry (UPLC-MS/MS) based diagnostic method that would generalize FS-C4BP as a clinical EOC biomarker. Glycopeptides derived from 20 μL of trypsin-digested serum glycoprotein were analyzed via UPLC equipped with an electrospray ionization time-of-flight mass spectrometer. This UPLC-MS/MS-based diagnostic method was optimized for FS-C4BP and validated using sera from 119 patients with EOC and 127 women without cancer. A1958 (C4BP peptide with two fully sialylated biantennary glycans) was selected as a marker of FS-C4BP because its level in serum was highest among FS-C4BP family members. Preparation and UPLC-MS/MS were optimized for A1958, and performance and robustness were significantly improved relative to our previous method. An area under the curve analysis of the FS-C4BP index receiver operating characteristic curve revealed that the ratio between A1958 and A1813 (C4BP peptide with two partially sialylated biantennary glycans) reached 85%. A combination of the FS-C4BP index and carbohydrate antigen-125 levels further enhanced the sensitivity and specificity. © 2017 The Authors. Biomedical Chromatography published by John Wiley & Sons Ltd.

  10. UPLC–MS/MS for the determination of azilsartan in beagle dog plasma and its application in a pharmacokinetics study

    Directory of Open Access Journals (Sweden)

    Cheng Gong

    2015-06-01

    Full Text Available The purpose of the study is to develop an ultra performance liquid chromatography-tandem mass spectrometry (UPLC–MS/MS to determinate the concentration of azilsartan in the dog plasma. After precipitated by methanol, the plasma sample containing azilsartan and diazepam (internal standard, IS was determined by UPLC–MS/MS. The mobile phase consisted of acetonitrile-water was pumped at a flow rate of 0.3 ml/min in gradient elution. Kinetex 2.6 μ XB-C18 column (50 × 2.1 mm, 100 Å; Phenomenex, USA were used for LC separations. The column temperature was 30 °C and the injection volume was 5 μl. The electrospray ionization (ESI and multiple reaction monitoring (MRM were applied at the transitions of m/z 457 → 279 (azilsartan and m/z 285 → 193 (diazepam, respectively. The developed method was identified a good linearity over a concentration range of 2.5–5000 ng/ml. The lower limit of quantitation (LLOQ was 2.5 ng/ml. The intra-day and inter-day precision (relative standard deviation, RSD% were less than 10% and accuracy (relative error, RE % was less than 5% at three quality control levels. The extraction recovery of azilsartan at three quality control levels were 82.41 ± 0.68%, 98.66 ± 11.00%, 102.43 ± 0.82%. And the recovery for IS (100 ng/ml was 91.75 ± 0.54%. A validated UPLC–MS/MS method was firstly developed for the quantification of azilsartan in dog plasma and it was applied to the pharmacokinetics study.

  11. Photolysis of sulfamethoxypyridazine in various aqueous media: Aerobic biodegradation and identification of photoproducts by LC-UV–MS/MS

    Energy Technology Data Exchange (ETDEWEB)

    Khaleel, Nareman D.H., E-mail: drndahshan@yahoo.com [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Leuphana University Lüneburg, C13, DE-21335 Lüneburg (Germany); Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522 (Egypt); Mahmoud, Waleed M.M. [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Leuphana University Lüneburg, C13, DE-21335 Lüneburg (Germany); Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522 (Egypt); Hadad, Ghada M.; Abdel-Salam, Randa A. [Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522 (Egypt); Kümmerer, Klaus, E-mail: Klaus.Kuemmerer@uni.leuphana.de [Sustainable Chemistry and Material Resources, Institute of Sustainable and Environmental Chemistry, Leuphana University Lüneburg, C13, DE-21335 Lüneburg (Germany)

    2013-01-15

    Highlights: ► Sulfonamides are one of the most extensively used antibiotics in human and veterinary medicine. ► Sulfamethoxypyridazine (SMP) underwent photodegradation in three different media. ► SMP was not readily biodegradable. ► SMP and some of its degradation products were identified by LC-UV–MS/MS. -- Abstract: Sulfonamides are one of the most frequently used antibiotics worldwide. Therefore, mitigation processes such as abiotic or biotic degradation are of interest. Photodegradation and biodegradation are the potentially significant removal mechanisms for pharmaceuticals in aquatic environments. The photolysis of sulfamethoxypyridazine (SMP) using a medium pressure Hg-lamp was evaluated in three different media: Millipore water pH 6.1 (MW), effluent from sewage treatment plant pH 7.6 (STP), and buffered demineralized water pH 7.4 (BDW). Identification of transformation products (TPs) was performed by LC-UV–MS/MS. The biodegradation of SMP using two tests from the OECD series was studied: Closed Bottle test (OECD 301 D), and Manometric Respirometry test (OECD 301 F). In biodegradation tests, it was found that SMP was not readily biodegradable so it may pose a risk to the environment. The results showed that SMP was removed completely within 128 min of irradiation in the three media, and the degradation rate was different for each investigated type of water. However, dissolved organic carbon (DOC) was not removed in BDW and only little DOC removal was observed in MW and STP, thus indicating the formation of TPs. Analysis by LC-UV–MS/MS revealed new TPs formed. The hydroxylation of SMP represents the main photodegradation pathway.

  12. RAId_aPS: MS/MS analysis with multiple scoring functions and spectrum-specific statistics.

    Science.gov (United States)

    Alves, Gelio; Ogurtsov, Aleksey Y; Yu, Yi-Kuo

    2010-11-16

    Statistically meaningful comparison/combination of peptide identification results from various search methods is impeded by the lack of a universal statistical standard. Providing an E-value calibration protocol, we demonstrated earlier the feasibility of translating either the score or heuristic E-value reported by any method into the textbook-defined E-value, which may serve as the universal statistical standard. This protocol, although robust, may lose spectrum-specific statistics and might require a new calibration when changes in experimental setup occur. To mitigate these issues, we developed a new MS/MS search tool, RAId_aPS, that is able to provide spectrum-specific-values for additive scoring functions. Given a selection of scoring functions out of RAId score, K-score, Hyperscore and XCorr, RAId_aPS generates the corresponding score histograms of all possible peptides using dynamic programming. Using these score histograms to assign E-values enables a calibration-free protocol for accurate significance assignment for each scoring function. RAId_aPS features four different modes: (i) compute the total number of possible peptides for a given molecular mass range, (ii) generate the score histogram given a MS/MS spectrum and a scoring function, (iii) reassign E-values for a list of candidate peptides given a MS/MS spectrum and the scoring functions chosen, and (iv) perform database searches using selected scoring functions. In modes (iii) and (iv), RAId_aPS is also capable of combining results from different scoring functions using spectrum-specific statistics. The web link is http://www.ncbi.nlm.nih.gov/CBBresearch/Yu/raid_aps/index.html. Relevant binaries for Linux, Windows, and Mac OS X are available from the same page.

  13. Photolysis of sulfamethoxypyridazine in various aqueous media: Aerobic biodegradation and identification of photoproducts by LC-UV–MS/MS

    International Nuclear Information System (INIS)

    Khaleel, Nareman D.H.; Mahmoud, Waleed M.M.; Hadad, Ghada M.; Abdel-Salam, Randa A.; Kümmerer, Klaus

    2013-01-01

    Highlights: ► Sulfonamides are one of the most extensively used antibiotics in human and veterinary medicine. ► Sulfamethoxypyridazine (SMP) underwent photodegradation in three different media. ► SMP was not readily biodegradable. ► SMP and some of its degradation products were identified by LC-UV–MS/MS. -- Abstract: Sulfonamides are one of the most frequently used antibiotics worldwide. Therefore, mitigation processes such as abiotic or biotic degradation are of interest. Photodegradation and biodegradation are the potentially significant removal mechanisms for pharmaceuticals in aquatic environments. The photolysis of sulfamethoxypyridazine (SMP) using a medium pressure Hg-lamp was evaluated in three different media: Millipore water pH 6.1 (MW), effluent from sewage treatment plant pH 7.6 (STP), and buffered demineralized water pH 7.4 (BDW). Identification of transformation products (TPs) was performed by LC-UV–MS/MS. The biodegradation of SMP using two tests from the OECD series was studied: Closed Bottle test (OECD 301 D), and Manometric Respirometry test (OECD 301 F). In biodegradation tests, it was found that SMP was not readily biodegradable so it may pose a risk to the environment. The results showed that SMP was removed completely within 128 min of irradiation in the three media, and the degradation rate was different for each investigated type of water. However, dissolved organic carbon (DOC) was not removed in BDW and only little DOC removal was observed in MW and STP, thus indicating the formation of TPs. Analysis by LC-UV–MS/MS revealed new TPs formed. The hydroxylation of SMP represents the main photodegradation pathway

  14. High throughput LC-MS/MS method for the simultaneous analysis of multiple vitamin D analytes in serum.

    Science.gov (United States)

    Jenkinson, Carl; Taylor, Angela E; Hassan-Smith, Zaki K; Adams, John S; Stewart, Paul M; Hewison, Martin; Keevil, Brian G

    2016-03-01

    Recent studies suggest that vitamin D-deficiency is linked to increased risk of common human health problems. To define vitamin D 'status' most routine analytical methods quantify one particular vitamin D metabolite, 25-hydroxyvitamin D3 (25OHD3). However, vitamin D is characterized by complex metabolic pathways, and simultaneous measurement of multiple vitamin D metabolites may provide a more accurate interpretation of vitamin D status. To address this we developed a high-throughput liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to analyse multiple vitamin D analytes, with particular emphasis on the separation of epimer metabolites. A supportive liquid-liquid extraction (SLE) and LC-MS/MS method was developed to quantify 10 vitamin D metabolites as well as separation of an interfering 7α-hydroxy-4-cholesten-3-one (7αC4) isobar (precursor of bile acid), and validated by analysis of human serum samples. In a cohort of 116 healthy subjects, circulating concentrations of 25-hydroxyvitamin D3 (25OHD3), 3-epi-25-hydroxyvitamin D3 (3-epi-25OHD3), 24,25-dihydroxyvitamin D3 (24R,25(OH)2D3), 1,25-dihydroxyvitamin D3 (1α,25(OH)2D3), and 25-hydroxyvitamin D2 (25OHD2) were quantifiable using 220μL of serum, with 25OHD3 and 24R,25(OH)2D3 showing significant seasonal variations. This high-throughput LC-MS/MS method provides a novel strategy for assessing the impact of vitamin D on human health and disease. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Assess, compare and enhance the status of Persons with Multiple Sclerosis (MS) in Europe

    DEFF Research Database (Denmark)

    Pugliatti, M; Eskic, D; Mikolcić, T

    2012-01-01

    Persons with multiple sclerosis (PwMS) experience health-related quality of life (HRQoL) problems greatly differing across Europe, and the European Union (EU) faces deep inequalities in MS management from country to country. Through the establishment of a European MS Register (EUReMS), an effective...

  16. HPLC-ESI-MS/MS analysis of oxidized di-caffeoylquinic acids generated by metalloporphyrin-catalyzed reactions

    Directory of Open Access Journals (Sweden)

    Michel D. Santos

    2008-01-01

    Full Text Available This paper reports an HPLC-ESI-MS/MS investigation on the oxidation of 3,5- and 4,5- dicaffeoylquinic acid using iron(III tetraphenylporphyrin chloride as catalyst. Two major mono-oxidised products of the quinic acid moiety have been identified for both compounds. However, only the 4,5-derivative afforded two different tri-oxo products. Thus, it seems that the oxidation pattern depends on the number and positions of the caffeic acid moieties present in caffeoylquinic acid molecules.

  17. HPLC-ESI-MS/MS analysis of oxidized di-caffeoylquinic acids generated by metalloporphyrin-catalyzed reactions

    International Nuclear Information System (INIS)

    Santos, Michel D.; Lopes, Norberto P.; Iamamoto, Yassuko

    2008-01-01

    This paper reports an HPLC-ESI-MS/MS investigation on the oxidation of 3,5- and 4,5- dicaffeoylquinic acid using iron(III) tetraphenylporphyrin chloride as catalyst. Two major mono-oxidised products of the quinic acid moiety have been identified for both compounds. However, only the 4,5-derivative afforded two different tri-oxo products. Thus, it seems that the oxidation pattern depends on the number and positions of the caffeic acid moieties present in caffeoylquinic acid molecules. (author)

  18. HPLC-ESI-MS/MS analysis of oxidized di-caffeoylquinic acids generated by metalloporphyrin-catalyzed reactions

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Michel D.; Lopes, Norberto P. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Fisica e Quimica]. E-mail: npelopes@fcfrp.usp.br; Iamamoto, Yassuko [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Quimica

    2008-07-01

    This paper reports an HPLC-ESI-MS/MS investigation on the oxidation of 3,5- and 4,5- dicaffeoylquinic acid using iron(III) tetraphenylporphyrin chloride as catalyst. Two major mono-oxidised products of the quinic acid moiety have been identified for both compounds. However, only the 4,5-derivative afforded two different tri-oxo products. Thus, it seems that the oxidation pattern depends on the number and positions of the caffeic acid moieties present in caffeoylquinic acid molecules. (author)

  19. Targeted LC-MS/MS method for quantification of Plant Lignans and Enterolignans in Biofluids from Humans and Pigs

    DEFF Research Database (Denmark)

    Nørskov, Natalja; Olsen, Anja; Tjønneland, Anne

    2015-01-01

    Lignans have gained nutritional interest due to their promising role in the prevention of lifestyle diseases. However, epidemiological studies are in need of more evidence to link the intake of lignans to this promising role. In this context, it is necessary to study large population groups...... to obtain sufficient statistical power. Therefore, there is a demand for fast, sensitive, and accurate methods for quantitation with high throughput of samples. This paper presents a validated LC-MS/MS method for the quantitation of eight plant lignans (matairesinol, hydroxymatairesinol...

  20. Combination of LC-ICP-MS, LC-MS and NMR for investigation of the oxidative degradation of selenomethionine

    DEFF Research Database (Denmark)

    Gammelgaard, B.; Cornett, Claus; Olsen, J.

    2003-01-01

    Selenomethionine (SeMet) was oxidized by heating an acidic solution with hydrogen peroxide. Samples were taken before and during the oxidation process. The oxidation products were separated by cation exchange chromatography followed by ICP-MS detection to identify the selenium containing compounds...... as well as electrospray ionization MS detection to determine the masses of the degradation products. Furthermore, the samples were analyzed by Se-77-NMR. The first appearing degradation product was selenomethionine selenoxide, which was converted via the deaminated selenoxide to methane seleninic acid...

  1. Screening for Anabolic Steroids in Urine of Forensic Cases Using Fully Automated Solid Phase Extraction and LC–MS-MS

    DEFF Research Database (Denmark)

    Andersen, David Wederkinck; Linnet, Kristian

    2014-01-01

    and solid phase extraction followed by analysis by liquid chromatography-tandem mass spectrometry (LC-MS-MS) using electrospray ionization with adduct formation for two compounds. Urine samples from 580 forensic cases were analyzed to determine the T/E ratio and occurrence of exogenous anabolic steroids....... Extraction recoveries ranged from 77 to 95%, matrix effects from 48 to 78%, overall process efficiencies from 40 to 54% and the lower limit of identification ranged from 2 to 40 ng/mL. In the 580 urine samples analyzed from routine forensic cases, 17 (2.9%) were found positive for one or more anabolic...

  2. Misleading measures in Vitamin D analysis: A novel LC-MS/MS assay to account for epimers and isobars

    Directory of Open Access Journals (Sweden)

    Petroczi Andrea

    2011-05-01

    Full Text Available Abstract Background Recently, the accuracies of many commercially available immunoassays for Vitamin D have been questioned. Liquid chromatography tandem mass spectrometry (LC- MS/MS has been shown to facilitate accurate separation and quantification of the major circulating metabolite 25-hydroxyvitamin-D3 (25OHD3 and 25-hydroxyvitamin-D2 (25OHD2 collectively termed as 25OHD. However, among other interferents, this method may be compromised by overlapping peaks and identical masses of epimers and isobars, resulting in inaccuracies in circulating 25OHD measurements. The aim of this study was to develop a novel LC-MS/MS method that can accurately identify and quantitate 25OHD3 and 25OHD2 through chromatographic separation of 25OHD from its epimers and isobars. Methods A positive ion electrospray ionisation (ESI LC-MS/MS method was used in the Multiple Reaction Monitoring (MRM mode for quantification. It involved i liquid-liquid extraction, ii tandem columns (a high resolution ZORBAX C18 coupled to an ULTRON chiral, with guard column and inlet filter, iii Stanozolol-D3 as internal standard, and iv identification via ESI and monitoring of three fragmentation transitions. To demonstrate the practical usefulness of our method, blood samples were collected from 5 healthy male Caucasian volunteers; age range 22 to 37 years and 25OHD2, 25OHD3 along with co-eluting epimers and analogues were quantified. Results The new method allowed chromatographic separation and quantification of 25OHD2, 25OHD3, along with 25OHD3 epimer 3-epi-25OHD3 and isobars 1-α-hydroxyvitamin-D3 (1αOHD3, and 7-α-hydroxy-4-cholesten-3-one (7αC4. The new assay was capable of detecting 0.25 ng/mL of all analytes in serum. Conclusions To our knowledge, this is the first specific, reliable, reproducible and robust LC-MS/MS method developed for the accurate detection of 25OHD (Vitamin D. The method is capable of detecting low levels of 25OHD3 and 25OHD2 together with chromatographic

  3. Determination of post-culture processing with carbohydrates by MALDI-MS and TMS derivatization GC-MS.

    Science.gov (United States)

    Wunschel, David S; Wahl, Karen L; Melville, Angela M; Sorensen, Christina M; Colburn, Heather A; Valentine, Nancy B; Stamper, Casey L

    2011-10-15

    Biological materials generally require stabilization to retain activity or viability in a dry form. A number of industrial products, such as vaccines, probiotics and biopesticides have been produced as dry preparations. The same methods and materials used for stabilizing commercial microbial products may be applicable to preserving biothreat pathogens in a dry form. This is a likely step that may be encountered when looking at samples from terrorism attempts since only spores, such as those from Bacillus anthracis, are inherently stable when dried. The stabilizers for microbial preparations generally include one or more small carbohydrates. Different formulations have been reported for different industrial products and are often determined empirically. However sugar alcohols (mannitol and sorbitol) and disaccharides (lactose, sucrose and trehalose) are the common constituents of these formulations. We have developed an analytical method for sample preparation and detection of these simple carbohydrates using two complementary analytical tools, MALDI-MS and GC-MS. The native carbohydrates and other constituents of the formulation are detected by MALDI-MS as a screening tool. A longer and more detailed analysis is then used to specifically identify the carbohydrates by derivatization and GC-MS detection. Both techniques were tested against ten different types of stabilization recipes with Yersinia pestis cell mass cultured on different media types used as the biological component. A number of additional components were included in these formulations including proteins and peptides from serum or milk, polymers (e.g. poly vinyl pyrrolidone - PVP) and detergents (e.g. Tween). The combined method was characterized to determine several figures of merit. The accuracy of the method was 98% for MALDI-MS and 100% for GC-MS. The repeatability for detection of carbohydrates by MALDI-MS was determined to be 96%. The repeatability of compound identification by GC-MS was

  4. LC-MS/MS analysis of uncommon paracetamol metabolites derived through in vitro polymerization and nitration reactions in liquid nitrogen.

    Science.gov (United States)

    Trettin, Arne; Jordan, Jens; Tsikas, Dimitrios

    2014-09-01

    Paracetamol (acetaminophen, APAP) is a commonly used analgesic drug. Known paracetamol metabolites include the glucuronide, sulfate and mercapturate. N-Acetyl-benzoquinonimine (NAPQI) is considered the toxic intermediate metabolite of paracetamol. In vitro and in vivo studies indicate that paracetamol is also metabolized to additional poorly characterized metabolites. For example, metabolomic studies in urine samples of APAP-treated mice revealed metabolites such as APAP-sulfate-APAP and APAP-S-S-APAP in addition to the classical phase II metabolites. Here, we report on the development and application of LC-MS and LC-MS/MS approaches to study reactions of unlabelled and (2)H-labelled APAP with unlabelled and (15)N-labelled nitrite in aqueous phosphate buffers (pH 7.4) upon their immersion into liquid nitrogen (-196°C). In mechanistic studies, these reactions were also studied in aqueous buffer prepared in (18)O-labelled water. LC-MS and LC-MS/MS analyses were performed on a reverse-phase material (C18) using gradient elution (2mM ammonium acetate/acetonitrile), in positive and negative electrospray mode. We identified a series of APAP metabolites including di-, tri- and tetra-APAP, mono- and di-nitro-APAP and nitric ester of di-APAP. Our study indicates that nitrite induces oxidation, i.e., polymerization and nitration of APAP, when buffered APAP/nitrite solutions are immersed into liquid nitrogen. These reactions are specific for nitrite with respect to nitrate and do not proceed via intermediate formation of NAPQI. Potassium ions and physiological saline but not thiols inhibit nitrite- and shock-freeze-induced reactions of paracetamol. The underlying mechanism likely involves in situ formation of NO2 radicals from nitrite secondary to profound pH reduction (down to pH 1) and disproportionation. Polymeric paracetamol species can be analyzed as pentafluorobenzyl derivatives by LC-MS but not by GC-MS. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Accurate determination of ultra-trace levels of Ti in blood serum using ICP-MS/MS

    International Nuclear Information System (INIS)

    Balcaen, Lieve; Bolea-Fernandez, Eduardo; Resano, Martín; Vanhaecke, Frank

    2014-01-01

    Graphical abstract: -- Highlights: •Novel method for determination of Ti at ultra-trace levels in clinical samples (serum). •Novel method based on Ti(NH 3 ) 6 + reaction product ion formation and double mass selection using recently introduced ICP-QQQ instrumentation. •Lowest limits of detection ever obtained using quadrupole-based instrumentation for Ti. •Accurate determination of basal levels of Ti in blood serum. -- Abstract: Ti is frequently used in implants and prostheses and it has been shown before that the presence of these in the human body can lead to elevated Ti concentrations in body fluids such as serum and urine. As identification of the exact mechanisms responsible for this increase in Ti concentrations, and the risks associated with it, are not fully understood, it is important to have sound analytical methods that enable straightforward quantification of Ti levels in body fluids (for both implanted and non-implanted individuals). Until now, only double-focusing sector field ICP-mass spectrometry (SF-ICP-MS) offered limits of detection that are good enough to deal with the very low basal levels of Ti in human serum. This work reports on the development of a novel method for the accurate and precise determination of trace levels of Ti in human serum samples, based on the use of ICP-MS/MS. O 2 and NH 3 /He have been compared as reaction gases. While the use of O 2 did not enable to overcome all spectral interferences, it has been shown that conversion of Ti + ions into Ti(NH 3 ) 6 + cluster ions by using NH 3 /He as a reaction gas in an ICP-QQQ-MS system, operated in MS/MS mode, provided interference-free conditions and sufficiently low limits of detection, down to 3 ng L −1 (instrumental detection limit obtained for the most abundant Ti isotope). The accuracy of the method proposed was evaluated by analysis of a Seronorm Trace Elements Serum L-1 reference material and by comparing the results obtained with those achieved by means of SF-ICP-MS

  6. Clinical laboratory verification of thyroglobulin concentrations in the presence of autoantibodies to thyroglobulin: comparison of EIA, radioimmunoassay and LC MS/MS measurements in an Urban Hospital.

    Science.gov (United States)

    Wheeler, Sarah E; Liu, Li; Blair, Harry C; Sivak, Richard; Longo, Nancy; Tischler, Jeffery; Mulvey, Kathryn; Palmer, Octavia M Peck

    2017-12-08

    Thyroglobulin (Tg) measurements assess recurrence in post-thyroidectomy thyroid cancer patients. Tg measurements by enzyme immunoassays (EIA) can be falsely elevated by interference from Tg autoantibodies (TgAb). Radioimmunoassay (RIA) is less susceptible to TgAb interference and has been the standard-of-care test for TgAb positive patients. Recently developed liquid chromatography tandem mass spectrometry (LC-MS/MS) methods may eliminate TgAb interference. We assessed the performance of Tg measurements by EIA, RIA and LC-MS/MS to evaluate TgAb interference differences. We measured TgAb and Tg in 50 plasma samples from 40 patients in whom Tg measurement was part of their routine follow-up and 10 healthy volunteers. Discrepancy between EIA and both LC-MS/MS and RIA was observed at low Tg concentrations (≤ 7.55 ng/mL) in TgAb positive specimens (LC-MS/MS = 1.9 * EIA - 0.03, r = 0.68). RIA and LC-MS/MS Tg measurements in TgAb positive specimens with low Tg concentrations had improved correlation but demonstrated bias (LC MS/MS = 0.6 * RIA - 1.4, r = 0.90). Disagreement between methods may be attributed to LC-MS/MS reported Tg concentrations as undetectable compared to RIA. It seems likely that most discrepant cases are falsely elevated in RIA due to TgAb interference, however, some cases appear below the detection limit of LC-MS/MS; implementation of LC-MS/MS by clinicians will require lower detection limits.

  7. Characterization and Clearance of m/s Sigyn

    International Nuclear Information System (INIS)

    Jiselmark, Jonatan; Vreede, Patrick

    2016-01-01

    M/s Sigyn was a 2044 ton ship that transported contaminated material between 1982 and 2013. Most of the transports were with spent nuclear fuel between Swedish nuclear power plants and the Swedish fuel repository, Clab. In addition to spent fuel, m/s Sigyn also transported big contaminated components, from nuclear power plants in Europe, to Studsvik for analysis or decontamination and melting. She also transported components from Swedish nuclear power plants to final disposal of short lived waste, SFR. Even though all transported items have been cleaned, checked and wrapped with plastics, some activity ended up as contamination onboard. In December 2013 it was decided that m/s Sigyn was subject for decommissioning due to her age. This Paper describes the method in which the activity onboard m/s Sigyn was characterized and clearance levels were calculated. This method for radiological characterization and clearance has recently been developed in Sweden, the method is efficient in that it does not need a big pre characterization survey. Only the nuclide distribution and history of the object, is needed to start the final survey. In the future there will be further development of the method, making it possible to reduce the number of measurements even more. This will further optimize the method and reduce the cost for final surveys and clearance. (authors)

  8. Report on the survey of geothermal development at Okushiri Island, Hokkaido. Geochemical survey (GC/MS and MS method); Hokkaido Okushiritou chinetsu kaihatsu chosa chikagaku chosa (GC/MS and MS ho) hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-09-01

    To elucidate chemical components of soil gas in the Okushiri Island area, soil gas was collected by the method using charcoal adsorbent, and analysis was made by the GC/MS method. Out of the 19 measuring points, 17 points were set up near the measuring points in the FY 1998 survey by the finger print method. At the same measuring points, analytical survey by the MS method was also conducted to sort the type of soil gas. As a result of the GC/MS analysis, xylene or ethyl benzene was detected at 12 measuring points of all 19 measuring points, and from the distribution, it was predicted that there were anomaly zones in the district along the road of the Okushiri Island line and the district southward from the 5.8K Pass. These results were in harmony with the results of the survey by the finger print method. As to the sorting of soil gas based on the results of the MS analysis, the results were different at 8 measuring points from those of the survey by the finger print method in FY 1998. It was considered that the cause was the accidental vaporization of a large quantity of acetaldehyde, and acetaldehyde was regarded as a noise gas component that does not reflect the geothermal structure. (NEDO)

  9. Determination of neptunium in soil by ICP-MS

    International Nuclear Information System (INIS)

    Ayranov, M.; Kraehenbuehl, U.

    2005-01-01

    A fast and simple method for the determination of 237 Np in soil is presented. The borate fusion decreases the sample pre-treatment time and a TEVA extraction chromatography separates neptunium from uranium and the interfering matrix components. A comparison of the sensitivities of alpha spectrometry and sector field ICP-MS for determination of 237 Np is presented. (orig.)

  10. CE-TOF/MS: fundamental concepts, instrumental considerations and applications.

    Science.gov (United States)

    Staub, Aline; Schappler, Julie; Rudaz, Serge; Veuthey, Jean-Luc

    2009-05-01

    This review discusses the fundamental principles of TOF analyzers and covers the great progress that has been made in this area in recent years (i.e. orthogonal acceleration, reflectron). This paper also gives an overview of applications performed by CE coupled to TOF/MS detection. The main domains of interest include the analysis of biomolecules and natural compounds.

  11. A Dicey Strategy To Get Your M&Ms.

    Science.gov (United States)

    Nisbet, Steven; Jones, Graham; Langrall, Cynthia; Thornton, Carol

    2000-01-01

    Describes and analyzes a learning episode in which two children in year 4 interact with each other and their teacher while playing a probability game involving chocolate M&Ms. Children developed key ideas in probability from a game that was designed to produce cognitive conflict. (ASK)

  12. GC – MS Characterization of Degutted White Grubs' Fatty Acids ...

    African Journals Online (AJOL)

    Fatty acids composition of white grubs examined by GC- MS identified 19 different fatty acids; 11 saturated, 7 monoene and a cyclopropaneoctanoate. The identified ones are Methyl tetradecanoate (C14:0), Methyl dodecanoate (C12:0), Methyl cis – 9 - octadecenote (C18:1), Methyl(7E) – 7 – hexadecenoate (C16:1), Methyl ...

  13. Neuroimaging (NMR) in the assessment of multiple sclerosis (MS)

    International Nuclear Information System (INIS)

    Gambi, D.; Uncini, A.

    1990-01-01

    Clinical well defined patients with MS have been submitted to series of controls of NMR investigations after an attack of the disease and during 12 months in order to organize a methodology useful to analyze patients in different periods or stages of the disease, when new lesions can develop. (author). 11 refs.; 2 figs.; 5 tabs

  14. Someone You Know Has MS: A Book for Families

    Science.gov (United States)

    ... very often. For Children and Teenagers | 10 Some Hard Things Some Good Things Doctors can’t cure MS ... of things to do with feelings that are hard to talk about. Here are some things Michael does: Draws a picture. Makes something out ...

  15. Analysis of banned veterinary drugs and herbicide residues in shellfish by liquid chromatography-tandem mass spectrometry (LC/MS/MS) and gas chromatography-tandem mass spectrometry (GC/MS/MS)

    International Nuclear Information System (INIS)

    Chang, Geng-Ruei; Chen, Hui-Shan; Lin, Feng-Yi

    2016-01-01

    Seafood safety is a crucial public health concern for consumers. In this study, we applied a validated method to analyze the residue of banned veterinary drugs in shellfish, namely chloramphenicol, malachite green, leucomalachite green, and nitrofuran metabolites; additionally, the QuEChERS method was employed to detect 76 herbicides by LC/MS/MS and GC/MS/MS. In total, 42 shellfish samples, which included hard clams, freshwater clams, and oysters, were collected from aquafarms and production areas in Taiwan during 2012. Our results revealed 3.8 ng/g of chloramphenicol in one hard clam, 19.9–32.1 ng/g of ametryn in two hard clams, 16.1–60.1 ng/g of pendimethalin in four hard clams, and 17.0 ng/g of mefenacet in one oyster, indicating that 19.1% of the samples contained residues from banned veterinary drugs and pesticides. These data can be used to monitor the residue of veterinary drugs and pesticides in aquatic organisms and as a reference for food safety. - Highlights: • A certified method was employed for analyzing residues of banned veterinary drugs and herbicides in shellfish samples. • The trace levels of chloramphenicol, ametryn, pendimethalin were detected in hard clam samples. • For ensuring food safety, continual monitoring of aquatic products is necessary.

  16. 76 FR 53531 - Environmental Impact Statement: Hancock County, MS

    Science.gov (United States)

    2011-08-26

    ...)] Environmental Impact Statement: Hancock County, MS AGENCY: Federal Highway Administration (FHWA), Department Of... that an environmental impact statement will be prepared for a proposed highway project in Hancock... an Environmental Impact Statement (EIS) for the proposed widening and/or realignment of State Route...

  17. 3400 m/s deuterium pellet injector for Tore Supra

    International Nuclear Information System (INIS)

    Perin, J.P.; Geraud, A.

    1995-01-01

    This paper reports on the Tore Supra high velocity pellet injector which was built in Grenoble and after qualification tests installed on Tore Supra Tokomak where it is used for plasma and ablation studies. By using a two stage light gas gun (TSG) and two cells (φ = 3 mm or 4 mm), unsupported pellets pellets (1 to 3.5 10 21 atoms) made directly in the gun by > [1] have been launched into Tore Supra plasma at speeds between 2400m/s and 3400m/s with a reliability of 80%. These higher pellets velocities (> 2500 m/s) [2] are obtained by the optimization of a TSG and the search for the cryogenic conditions of freezing deuterium with good mechanical properties. In particular, the impurities concentration in deuterium during the condensation process has been studied. Several tens pellets have been injected into ohmically and ICR heated plasma and during LH current drive experiments with a good reliability in the range of 3000m/s. These experiments allowed us to extend significantly the ablation data base. Central penetrations can be reached even for high temperatures plasma (3-5 keV) and very peaked density profiles have been obtained in ohmically and ICR heated plasmas A transient improved confinement regime is then observed, which presents some features similar to the PEP regime obtained on JET. (orig.)

  18. Adsorption gas chromatography with 150-ms {sup 216}Po

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, A [Bern Univ. (Switzerland); Gaeggeler, H W; Tuerler, A [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    A gas chromatography apparatus was developed, which allows experiments with volatile radionuclides having shorter half-lives than one second. This apparatus was tested with the 150-ms isotope {sup 216}Po. Experimental data were compared with a Monte Carlo model to determine the adsorption enthalpy {Delta}H{sub a}. (author) 2 figs., 2 refs.

  19. Disinfection of bacteriophage MS2 by copper in water.

    Science.gov (United States)

    Armstrong, Andrew M; Sobsey, Mark D; Casanova, Lisa M

    2017-09-01

    Households that lack piped water supply are often forced to meet water needs by storing in the home, leaving water vulnerable to contamination by viruses. Storage in copper containers can potentially prevent this type of contamination, but the inactivation kinetics of viruses by copper need to be described to make appropriate storage recommendations. This work characterized inactivation kinetics of bacteriophage MS2 as a surrogate for enteric viruses by dissolved ionic copper in water. Reduction of MS2 increased with increasing doses of copper. At 0.3 mg/L, there was a 1.8-log 10 reduction of MS2 within 6 h. At 1 and 3 mg/L, 2-2.5 log 10 inactivation could be achieved between 6 and 24 h. Parameters for the Chick-Watson, Hom, and One Hit-Two Population models of inactivation were calculated and evaluated, all of which demonstrated strong goodness-of-fit and predictability at various contact times. Copper inactivates MS2 under controlled conditions at doses between 0.3 and 3 mg/L. Although requiring longer contact times than conventional disinfectants, it is a candidate for improving the safety of stored drinking water.

  20. Comparative LC-MS: A landscape of Peaks and Valleys

    NARCIS (Netherlands)

    America, A.H.P.; Cordewener, J.H.G.

    2008-01-01

    Quantitative proteomics approaches using stable isotopes are well-known and used in many labs nowadays. More recently, high resolution quantitative approaches are reported that rely on LC-MS quantitation of peptide concentrations by comparing peak intensities between multiple runs obtained by

  1. Geographical origin classification of olive oils by PTR-MS

    NARCIS (Netherlands)

    Araghipour, N.; Colineau, J.; Koot, A.H.; Akkermans, W.; Rojas, J.M.M.; Beauchamp, J.; Wisthaler, A.; Märk, T.D.; Downey, G.; Guillou, C.; Mannina, L.; Ruth, van S.M.

    2008-01-01

    The volatile compositions of 192 olive oil samples from five different European countries were investigated by PTR-MS sample headspace analysis. The mass spectra of all samples showed many masses with high abundances, indicating the complex VOC composition of olive oil. Three different PLS-DA models

  2. 76 FR 5119 - Television Broadcasting Services; Jackson, MS

    Science.gov (United States)

    2011-01-28

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 [DA 11-96; MB Docket No. 11-8; RM-11618] Television Broadcasting Services; Jackson, MS AGENCY: Federal Communications Commission. ACTION: Proposed... CFR 1.415 and 1.420. List of Subjects in 47 CFR Part 73 Television, Television broadcasting. For the...

  3. 76 FR 19275 - Television Broadcasting Services; Jackson, MS

    Science.gov (United States)

    2011-04-07

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 [MB Docket No. 11-8; RM-11618, DA 11-516] Television Broadcasting Services; Jackson, MS AGENCY: Federal Communications Commission. ACTION: Final rule... review Act, see 5 U.S.C. 801(a)(1)(A). List of Subjects in 47 CFR Part 73 Television. Federal...

  4. Some practical applications of an ICP-MS instrument

    International Nuclear Information System (INIS)

    Meddings, B.; Ng, R.

    1987-01-01

    An early model commercial ICP-MS instrument (PlasmaQuad from VG Isotopes Limited) was acquired more than two years ago. As a typical analytical laboratory in the metallurgical field, the application of the ICP-MS technique to real sample analysis is the authors prime concern. The process of introducing this state-of-the-art instrument into routine analysis will be described. The modifications and limitations necessary to achieve acceptable precision under normal working conditions will be outlined. In most cases, practical problems can be circumvented with some sacrifice in analytical performance in the area of detection limits and dynamic range. In this presentation, specific applications of the ICP-MS technique in the authors laboratory will be discussed. These include trace analysis on high purity metals such as copper, aluminum, cobalt, nickel etc., on refinery feed samples such as nickel sulfate, mixed cobalt and nickel sulfide, cobalt cathode, samarium oxide etc., on alloys such as cobalt-samarium magnetic materials, nickel or cobalt based alloys used in turbine blades etc. Other applications such as the determination of uranium in phosphate rock, trace analysis on fertilizers, water samples and high purity acids will also be mentioned. The solutions to the practical problems encountered in these applications will be discussed. The analytical power of the ICP-MS technique for real sample analysis will be assessed

  5. Occurrence of acidic PPCPs in surface and drinking waters by UHPLC-MS/MS

    Science.gov (United States)

    Picó, Yolanda; Carmona, Eric; Andreu, Vicente

    2015-04-01

    The term "emerging pollutants" stands for the substances that are released in the environment for which currently no regulations are established for their environmental monitoring. Their occurrence is reported worldwide in a range of aquatic environments, such as lakes, rivers, freshwater catchments, estuaries, reservoirs and marine waters. However, there are still few studies on their occurrence, levels and distribution in River Basins from Spain. This study is aimed at contributing information on the occurrence of three groups of emerging contaminants -licit and illicit drugs and personal care products- in the Turia River Basin. This River is a 280-km Mediterranean River with a flow rate 10.43 m3/s (Carmona et al., 2011), which is born in the province of Teruel and flows near the Valencia city. It has been selected because it is a typical Mediterranean River heavily affected by drought. The most 14 drank waters in Spain were analyzed to determinate the occurrence of some emerging pollutants. Selected contaminants include more than 40 pharmaceuticals, 5 personal care products and two illicit drugs. These substances were determined with an Agilent Technologies HPLC linked with a Triple Quad LC/MS in positive and negative ion mode using for compound separation a Waters C18 analytical column of 2.1x50mm and 3.5 µm particle diameter from Sunfire. The optimal mobile phase was a gradient of 5mM Ammonium fluoride in water (mobile phase A) and 5mM Ammonium fluoride in methanol (mobile phase B), at a flow rate of 0.2mL/min with a gradient that starts with 30% of mobile phase B and increase until 95% at minute 12 and remains 13 minutes more. The analytes were extracted from 250 mL of water by solid-phase extraction using Strata-X cartridges, eluted with methanol, evaporated and dissolved in 250 µL of methanol (Carmona et al. 2014). This procedure provides acceptable recoveries (>70%) and relative standard deviation (RSDs < 20%) at the limits of quantification, which are

  6. Body composition differences between adults with multiple sclerosis and BMI-matched controls without MS.

    Science.gov (United States)

    Wingo, Brooks C; Young, Hui-Ju; Motl, Robert W

    2018-04-01

    Persons with multiple sclerosis (MS) have many health conditions related to overweight and obesity, but little is known about how body composition among those with MS compares to those without MS at the same weight. To compare differences in whole body and regional body composition between persons with and without MS matched for sex and body mass index (BMI). Persons with MS (n = 51) and non-MS controls (n = 51) matched for sex and BMI. Total mass, lean mass, fat mass, and percent body fat (%BF) of total body and arm, leg, and trunk segments were assessed using dual-energy X-ray absorptiometry (DXA). Men with MS had significantly less whole body lean mass (mean difference: 9933.5 ± 3123.1 g, p MS counterparts. Further, men with MS had significantly lower lean mass in the arm (p = 0.02) and leg (p MS. Men with MS had significantly higher %BF in all three regions (p MS. There were no differences between women with and without MS. We observed significant differences in whole body and regional body composition between BMI-matched men with and without MS. Additional research is needed to further explore differences in body composition, adipose distribution, and the impact of these differences on the health and function of men with MS. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. High-Throughput LC-MS/MS Method for Direct Quantification of Glucuronidated, Sulfated and Free Enterolactone in Human Plasma

    DEFF Research Database (Denmark)

    Nørskov, Natalja; Kyrø, Cecilie; Olsen, Anja

    2016-01-01

    Sulfation and glucuronidation constitute a major pathway in humans and may play an important role in biological activity of metabolites including the enterolignan, enterolactone. Because the aromatic structure of enterolactone has similarities to steroid metabolites, it was hypothesized that ente......Sulfation and glucuronidation constitute a major pathway in humans and may play an important role in biological activity of metabolites including the enterolignan, enterolactone. Because the aromatic structure of enterolactone has similarities to steroid metabolites, it was hypothesized......−MS/MS and a fluoroimmunoassay; however, most of these methods measure the total concentration of enterolactone, without any specification of its conjugation pattern. Here for the first time we present a high-throughput LC−MS/MS method to quantify enterolactone in its intact form as glucuronide, sulfate, and free enterolactone....... The method has shown good accuracy and precision at low concentration and very high sensitivity, with LLOQ for enterolactone sulfate at 16 pM, enterolactone glucuronide at 26 pM, and free enterolactone at 86 pM. The short run time of 2.6 min combined with simple sample clean up and high sensitivity make...

  8. Screening for anabolic steroids in urine of forensic cases using fully automated solid phase extraction and LC-MS-MS.

    Science.gov (United States)

    Andersen, David W; Linnet, Kristian

    2014-01-01

    A screening method for 18 frequently measured exogenous anabolic steroids and the testosterone/epitestosterone (T/E) ratio in forensic cases has been developed and validated. The method involves a fully automated sample preparation including enzyme treatment, addition of internal standards and solid phase extraction followed by analysis by liquid chromatography-tandem mass spectrometry (LC-MS-MS) using electrospray ionization with adduct formation for two compounds. Urine samples from 580 forensic cases were analyzed to determine the T/E ratio and occurrence of exogenous anabolic steroids. Extraction recoveries ranged from 77 to 95%, matrix effects from 48 to 78%, overall process efficiencies from 40 to 54% and the lower limit of identification ranged from 2 to 40 ng/mL. In the 580 urine samples analyzed from routine forensic cases, 17 (2.9%) were found positive for one or more anabolic steroids. Only seven different steroids including testosterone were found in the material, suggesting that only a small number of common steroids are likely to occur in a forensic context. The steroids were often in high concentrations (>100 ng/mL), and a combination of steroids and/or other drugs of abuse were seen in the majority of cases. The method presented serves as a fast and automated screening procedure, proving the suitability of LC-MS-MS for analyzing anabolic steroids. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. LC-ESI/MS/MS method for rapid screening and confirmation of 44 exogenous anabolic steroids in human urine.

    Science.gov (United States)

    Jeon, Byoung Wook; Yoo, Hye Hyun; Jeong, Eun Sook; Kim, Ho Jun; Jin, Changbae; Kim, Dong Hyun; Lee, Jaeick

    2011-09-01

    A sensitive and rapid method based on liquid chromatography-triple-quadrupole tandem mass spectrometry (LC-MS/MS) with electrospray ionization (ESI) has been developed and validated for the screening and confirmation of 44 exogenous anabolic steroids (29 parent steroids and 15 metabolites) in human urine. The method involves an enzymatic hydrolysis, liquid-liquid extraction, and detection by LC-MS/MS. A triple-quadrupole mass spectrometer was operated in positive ESI mode with selected reaction monitoring (SRM) mode for the screening and product ion scan mode for the confirmation. The protonated molecular ions were used as precursor ions for the SRM analysis and product ion scan. The intraday and interday precisions of the target analytes at concentrations of the minimum required performance levels for the screening were 2-14% and 2-15%, respectively. The limits of detection for the screening and confirmation method were 0.1-10 ng/mL and 0.2-10 ng/mL, respectively, for 44 steroids. This method was successfully applied to analysis of urine samples from suspected anabolic steroid abusers.

  10. Simultaneous Determination of 11 Compounds in Gualou Guizhi Granule and Pharmacokinetics Study by UPLC-MS/MS

    Directory of Open Access Journals (Sweden)

    Chengtao Sun

    2017-01-01

    Full Text Available A rapid and sensitive ultrafast performance liquid chromatography-tandem mass spectrometry method (UPLC-MS/MS was developed for the simultaneous determination of 11 compounds in Gualou Guizhi Granule (GLGZG, including liquiritin, isoliquiritin, liquirtin apioside, isoliquiritin apioside, liquiritigenin, isoliquiritigenin, glycyrrhizic acid, glycyrrhetinic acid, paeoniflorin, albiflorin, and paeoniflorin sulfonate in rat plasma. UPLC-MS/MS assay with negative ion mode was performed on a Waters CORTECS C18 (2.1 × 100 mm, 1.6 μm with the mobile phase consisting of 0.1% aqueous formic acid (A and acetonitrile (B in gradient elution at a flow rate of 0.25 mL·min−1. The method was linear for all analytes within the detection range (r≥0.9597. The inter- and intraday precision (RSD were 2.21–6.41% and 1.67–6.18%; the inter- and intraday accuracy (recover were 92.48–114.03% and 90.23–112.04%. And the recovery rate ranged from 81.30% to 108.22%. The matrix effect values obtained for analytes ranged from 88.91% to 113.32%. This validated method was successfully applied to a pharmacokinetics study in rats after oral administration of GLGZG.

  11. Fast Simultaneous Determination of 13 Nucleosides and Nucleobases in Cordyceps sinensis by UHPLC–ESI–MS/MS

    Directory of Open Access Journals (Sweden)

    Shi-Yu Zong

    2015-12-01

    Full Text Available A reliable ultra-high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UHPLC–ESI–MS/MS method for the fast simultaneous determination of 13 nucleosides and nucleobases in Cordyceps sinensis (C. sinensis with 2-chloroadenosine as internal standard was developed and validated. Samples were ultrasonically extracted in an ice bath thrice, and the optimum analyte separation was performed on an ACQUITY UPLCTM HSS C18 column (100 mm × 2.1 mm, 1.8 μm with gradient elution. All targeted analytes were separated in 5.5 min. Furthermore, all calibration curves showed good linear regression (r > 0.9970 within the test ranges, and the limits of quantitation and detection of the 13 analytes were less than 150 and 75 ng/mL, respectively. The relative standard deviations (RSDs of intra- and inter-day precisions were <6.23%. Recoveries of the quantified analytes ranged within 85.3%–117.3%, with RSD < 6.18%. The developed UHPLC–ESI–MS/MS method was successfully applied to determine nucleosides and nucleobases in 11 batches of C. sinensis samples from different regions in China. The range for the total content in the analyzed samples was 1329–2057 µg/g.

  12. Comparison of Protein Phosphatase Inhibition Assay with LC-MS/MS for Diagnosis of Microcystin Toxicosis in Veterinary Cases

    Directory of Open Access Journals (Sweden)

    Caroline E. Moore

    2016-03-01

    Full Text Available Microcystins are acute hepatotoxins of increasing global concern in drinking and recreational waters and are a major health risk to humans and animals. Produced by cyanobacteria, microcystins inhibit serine/threonine protein phosphatase 1 (PP1. A cost-effective PP1 assay using p-nitrophenyl phosphate was developed to quickly assess water and rumen content samples. Significant inhibition was determined via a linear model, which compared increasing volumes of sample to the log-transformed ratio of the exposed rate over the control rate of PP1 activity. To test the usefulness of this model in diagnostic case investigations, samples from two veterinary cases were tested. In August 2013 fifteen cattle died around two ponds in Kentucky. While one pond and three tested rumen contents had significant PP1 inhibition and detectable levels of microcystin-LR, the other pond did not. In August 2013, a dog became fatally ill after swimming in Clear Lake, California. Lake water samples collected one and four weeks after the dog presented with clinical signs inhibited PP1 activity. Subsequent analysis using liquid chromatography-mass spectrometry (LC-MS/MS detected microcystin congeners -LR, -LA, -RR and -LF but not -YR. These diagnostic investigations illustrate the advantages of using functional assays in combination with LC-MS/MS.

  13. A method for the determination of acrylamide in bakery products using ion trap LC-ESI-MS/MS.

    Science.gov (United States)

    Claus, Achim; Weisz, Georg M; Kammerer, Dietmar R; Carle, Reinhold; Schieber, Andreas

    2005-10-01

    Acrylamide levels of bakery products, e. g., bread and bread rolls, are usually below 100 microg/kg , often even below 50 microg/kg. Therefore, usual analytical methods which have an LOQ greater, not dbl equals 25 microg/kg are not sensitive enough for detailed investigations on acrylamide formation within these commodities. An improved method for trace level determination of acrylamide in bakery products was developed using ion trap LC-ESI-MS/MS. Samples were divided into crumbs and crusts to achieve an initial concentration by removing the crumbs since these are devoid of acrylamide. After sample extraction and clean-up using multimode SPE cartridges, further analyte enrichment was accomplished by solid-phase-supported liquid-liquid extraction with ethyl acetate prior to LC-MS/MS analysis. The method was evaluated using bread, bread rolls, alkali-baked bread rolls, and toast. LOQ was calculated from the confidence interval of the calibration curve and found to be 1.7 ng/mL, corresponding to 17 microg/kg of product. When crumbs and crusts were separated, an LOQ of 10.2 microg/kg of bakery product could be obtained. As demonstrated in preliminary comparative analyses, accuracy of the method met the requirements for determination of trace level acrylamide formation in bakery products. Mean recovery was 102.4% (CV 4.5%), intermediate reproducibility revealed a CV of 2.1%, and a repeatability of CV 6.0%.

  14. LC-MS/MS as an alternative for SDS-PAGE in blue native analysis of protein complexes.

    NARCIS (Netherlands)

    Wessels, H.C.T.; Vogel, R.O.; Heuvel, L.P.W.J. van den; Smeitink, J.A.M.; Rodenburg, R.J.T.; Nijtmans, L.G.J.; Farhoud, M.H.

    2009-01-01

    Two-dimensional blue native/SDS-PAGE is widely applied to investigate native protein-protein interactions, particularly those within membrane multi-protein complexes. MS has enabled the application of this approach at the proteome scale, typically by analysis of picked protein spots. Here, we

  15. LFQuant: a label-free fast quantitative analysis tool for high-resolution LC-MS/MS proteomics data.

    Science.gov (United States)

    Zhang, Wei; Zhang, Jiyang; Xu, Changming; Li, Ning; Liu, Hui; Ma, Jie; Zhu, Yunping; Xie, Hongwei

    2012-12-01

    Database searching based methods for label-free quantification aim to reconstruct the peptide extracted ion chromatogram based on the identification information, which can limit the search space and thus make the data processing much faster. The random effect of the MS/MS sampling can be remedied by cross-assignment among different runs. Here, we present a new label-free fast quantitative analysis tool, LFQuant, for high-resolution LC-MS/MS proteomics data based on database searching. It is designed to accept raw data in two common formats (mzXML and Thermo RAW), and database search results from mainstream tools (MASCOT, SEQUEST, and X!Tandem), as input data. LFQuant can handle large-scale label-free data with fractionation such as SDS-PAGE and 2D LC. It is easy to use and provides handy user interfaces for data loading, parameter setting, quantitative analysis, and quantitative data visualization. LFQuant was compared with two common quantification software packages, MaxQuant and IDEAL-Q, on the replication data set and the UPS1 standard data set. The results show that LFQuant performs better than them in terms of both precision and accuracy, and consumes significantly less processing time. LFQuant is freely available under the GNU General Public License v3.0 at http://sourceforge.net/projects/lfquant/. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Untargeted LC-MS/MS Profiling of Cell Culture Media Formulations for Evaluation of High Temperature Short Time Treatment Effects.

    Science.gov (United States)

    Floris, Patrick; McGillicuddy, Nicola; Albrecht, Simone; Morrissey, Brian; Kaisermayer, Christian; Lindeberg, Anna; Bones, Jonathan

    2017-09-19

    An untargeted LC-MS/MS platform was implemented for monitoring variations in CHO cell culture media upon exposure to high temperature short time (HTST) treatment, a commonly used viral clearance upstream strategy. Chemically defined (CD) and hydrolysate-supplemented media formulations were not visibly altered by the treatment. The absence of solute precipitation effects during media treatment and very modest shifts in pH values observed indicated sufficient compatibility of the formulations evaluated with the HTST-processing conditions. Unsupervised chemometric analysis of LC-MS/MS data, however, revealed clear separation of HTST-treated samples from untreated counterparts as observed from analysis of principal components and hierarchical clustering sample grouping. An increased presence of Maillard products in HTST-treated formulations contributed to the observed differences which included organic acids, observed particularly in chemically defined formulations, and furans, pyridines, pyrazines, and pyrrolidines which were determined in hydrolysate-supplemented formulations. The presence of Maillard products in media did not affect cell culture performance with similar growth and viability profiles observed for CHO-K1 and CHO-DP12 cells when cultured using both HTST-treated and untreated media formulations.

  17. Simultaneous Determination of Multi-Mycotoxins in Cereal Grains Collected from South Korea by LC/MS/MS

    Directory of Open Access Journals (Sweden)

    Dong-Ho Kim

    2017-03-01

    Full Text Available An improved analytical method compared with conventional ones was developed for simultaneous determination of 13 mycotoxins (deoxynivalenol, nivalenol, 3-acetylnivalenol, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, fumonisin B1, fumonisin B2, T-2, HT-2, zearalenone, and ochratoxin A in cereal grains by liquid chromatography-tandem mass spectrometry (LC/MS/MS after a single immunoaffinity column clean-up. The method showed a good linearity, sensitivity, specificity, and accuracy in mycotoxin determination by LC/MS/MS. The levels of 13 mycotoxins in 5 types of commercial grains (brown rice, maize, millet, sorghum, and mixed cereal from South Korea were determined in a total of 507 cereal grains. Mycotoxins produced from Fusarium sp. (fumonisins, deoxynivalenol, nivalenol, and zearalenone were more frequently (more than 5% and concurrently detected in all cereal grains along with higher mean levels (4.3–161.0 ng/g in positive samples than other toxins such as aflatoxins and ochratoxin A (less than 9% and below 5.2 ng/g in positive samples from other fungal species.

  18. In vitro dissolution profile study of mucolytic drug ambroxol hydrochloride from solid oral dosage form by UHPLC-MS/MS

    Directory of Open Access Journals (Sweden)

    Vujović Maja M.

    2017-01-01

    Full Text Available In this paper a simplified dissolution test was performed for the release of ambroxol from tablets according to the European Pharmacopoeia. In vitro, three different dissolution media; 0.1 M HCl pH 1.2, acetate buffer (ABS pH 4.5 and phosphate buffer (PBS pH 6.8 were used for the simulation of the gastrointestinal conditions at temperature of 37.0±0.5°C. The drug release was evaluated by a new ultra - high performance liquid chromatography (UHPLC - tandem mass spectrometry (MS/MS method. The method was validated to meet requirements as per ICH guidelines which include linearity, specificity, precision, accuracy and robustness. The corresponding dissolution profiles showed more than 80% drug release within 30 minutes without significant differences. Further, the developed and validated UHPLC-MS/MS method could find a useful application in the process of production, quality control and bioavailability/bioequivalence studies of new pharmaceutical formulations of drugs in order to achieve a safe therapeutic efficacy. [Projekat Ministarstva nauke Republike Srbije, br. 175045

  19. Identification and characterization of phenolics and terpenoids from ethanolic extracts of Phyllanthus species by HPLC-ESI-QTOF-MS/MS

    Institute of Scientific and Technical Information of China (English)

    Sunil Kumar; Awantika Singh; Brijesh Kumar

    2017-01-01

    Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-QTOF-MS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C8 column (250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and P. niruri.

  20. Detection of endocrine active substances in the aquatic environment in southern Taiwan using bioassays and LC-MS/MS.

    Science.gov (United States)

    Chen, Kuang-Yu; Chou, Pei-Hsin

    2016-06-01

    Endocrine active substances, including naturally occurring hormones and various synthetic chemicals have received much concern owing to their endocrine disrupting potencies. It is essential to monitor their environmental occurrence since these compounds may pose potential threats to biota and human health. In this study, yeast-based reporter assays were carried out to investigate the presence of (anti-)androgenic, (anti-)estrogenic, and (anti-)thyroid compounds in the aquatic environment in southern Taiwan. Liquid chromatography tandem mass spectrometry (LC-MS/MS) was also used to measure the environmental concentrations of selected endocrine active substances for assessing potential ecological risks and characterizing contributions to the endocrine disrupting activities. Bioassay results showed that anti-androgenic (ND-7489 μg L(-1) flutamide equivalent), estrogenic (ND-347 ng L(-1) 17β-estradiol equivalent), and anti-thyroid activities were detected in the dissolved and particulate phases of river water samples, while anti-estrogenic activities (ND-10 μg L(-1) 4-hydroxytamoxifen equivalent) were less often found. LC-MS/MS analysis revealed that anti-androgenic and estrogenic contaminants, such as bisphenol A, triclosan, and estrone were frequently detected in Taiwanese rivers. In addition, their risk quotient values were often higher than 1, suggesting that they may pose an ecological risk to the aquatic biota. Further identification of unknown anti-androgenic and estrogenic contaminants in Taiwanese rivers may be necessary to protect Taiwan's aquatic environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Determination of Urinary PAH Metabolites Using DLLME Hyphenated to Injector Port Silylation and GC-MS-MS.

    Science.gov (United States)

    Gupta, Manoj Kumar; Jain, Rajeev; Singh, Pratibha; Ch, Ratnasekhar; Mudiam, Mohana Krishna Reddy

    2015-06-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants and well-known carcinogens. Hydroxy derivatives of PAH are considered as biomarkers of PAH exposure, and there is a need to measure these metabolites at low concentrations. So, a precise and eco-friendly analytical method has been developed for rapid determination of PAH metabolites. For the first time, a new analytical method based on coupling of dispersive liquid-liquid microextraction (DLLME) with auto-injector port silylation (auto-IPS) followed by gas chromatography-tandem mass spectrometry (GC-MS-MS) analysis is reported for the analysis of seven urinary PAH metabolites. Factors affecting DLLME and IPS, such as type and volume of extraction and disperser solvent, pH, ionic strength, injector port temperature, volume of N,O-bis(trimethylsilyl)trifluoroacetamide and type of solvent were investigated. Under optimized conditions, the limit of detection and limit of quantification were found to be in the range of 1-9 and 3-29 ng/mL, respectively. Satisfactory recoveries of metabolites in urine samples in the range of 87-95% were found. The developed method has been successfully applied for the determination of PAH metabolites in urine samples of exposed workers. DLLME-auto-IPS-GC-MS-MS method is time, labor, solvent and reagent saving, which can be routinely used for the analysis of urinary PAH metabolites. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. SFC-MS/MS as an orthogonal technique for improved screening of polar analytes in anti-doping control.

    Science.gov (United States)

    Parr, Maria Kristina; Wuest, Bernhard; Naegele, Edgar; Joseph, Jan F; Wenzel, Maxi; Schmidt, Alexander H; Stanic, Mijo; de la Torre, Xavier; Botrè, Francesco

    2016-09-01

    HPLC is considered the method of choice for the separation of various classes of drugs. However, some analytes are still challenging as HPLC shows limited resolution capabilities for highly polar analytes as they interact insufficiently on conventional reversed-phase (RP) columns. Especially in combination with mass spectrometric detection, limitations apply for alterations of stationary phases. Some highly polar sympathomimetic drugs and their metabolites showed almost no retention on different RP columns. Their retention remains poor even on phenylhexyl phases that show different selectivity due to π-π interactions. Supercritical fluid chromatography (SFC) as an orthogonal separation technique to HPLC may help to overcome these issues. Selected polar drugs and metabolites were analyzed utilizing SFC separation. All compounds showed sharp peaks and good retention even for the very polar analytes, such as sulfoconjugates. Retention times and elution orders in SFC are different to both RP and HILIC separations as a result of the orthogonality. Short cycle times could be realized. As temperature and pressure strongly influence the polarity of supercritical fluids, precise regulation of temperature and backpressure is required for the stability of the retention times. As CO2 is the main constituent of the mobile phase in SFC, solvent consumption and solvent waste are considerably reduced. Graphical Abstract SFC-MS/MS vs. LC-MS/MS.

  3. UPLC-MS/MS-Based Profiling of Eicosanoids in RAW264.7 Cells Treated with Lipopolysaccharide

    Directory of Open Access Journals (Sweden)

    Jae Won Lee

    2016-04-01

    Full Text Available While both the pro- and anti-inflammatory effects of several eicosanoids have been widely studied, the degree of inflammation in cells that results from various eicosanoids has yet to be comprehensively studied. The objective of this study was to assess the effect of lipopolysaccharide (LPS treatment on eicosanoid content in RAW264.7 cells. An Ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS-based profiling method was used to analyze the eicosanoid contents of RAW264.7 cells treated with different LPS concentrations. The profiling data were subjected to statistical analyses, such as principal component analysis (PCA and hierarchical clustering analysis. LPS treatment increased nitric oxide production and secretion of pro-inflammatory cytokines, such as tumor necrosis factor-α and interleukin-6, in a concentration-dependent manner. In total, 79 eicosanoids were identified in the cells. RAW264.7 cells treated with different LPS concentrations were well differentiated in the PCA score plot. A heatmap was used to identify the eicosanoids that were up- or down-regulated according to the degree of inflammation and LPS concentration. Thirty-nine eicosanoids were upregulated and seven were down-regulated by LPS treatment in a concentration-dependent manner. Our novel UPLC-MS/MS technique can profile eicosanoids, and can evaluate the correlations between inflammation and eicosanoid metabolism.

  4. Thrombin generation correlates with disease duration in multiple sclerosis (MS): Novel insights into the MS-associated prothrombotic state.

    Science.gov (United States)

    Parsons, Martin Em; O'Connell, Karen; Allen, Seamus; Egan, Karl; Szklanna, Paulina B; McGuigan, Christopher; Ní Áinle, Fionnuala; Maguire, Patricia B

    2017-01-01

    Thrombin is well recognised for its role in the coagulation cascade but it also plays a role in inflammation, with enhanced thrombin generation observed in several inflammatory disorders. Although patients with multiple sclerosis (MS) have a higher incidence of thrombotic disease, thrombin generation has not been studied to date. The aim of this study was to characterise calibrated automated thrombography parameters in patients with relapsing-remitting MS (RRMS) and primary progressive MS (PPMS) in comparison to healthy controls (HCs). Calibrated automated thrombography was performed on platelet poor plasma from 15 patients with RRMS, 15 with PPMS and 19 HCs. We found that patients with RRMS generate thrombin at a significantly faster rate than the less inflammatory subtype, PPMS or HCs. In addition, the speed of thrombin generation was significantly correlated with time from clinical diagnosis in both subtypes. However, in RRMS the rate of thrombin generation was increased with increased time from clinical diagnosis, while in PPMS the rate of thrombin generation decreased with increased time from clinical diagnosis. These data likely reflect the differential active proinflammatory states in each MS subtype and provide novel mechanistic insights into the clinically relevant prothrombotic state observed in these patients.

  5. Combined use of ESI-QqTOF-MS and ESI-QqTOF-MS/MS with mass-spectral library search for qualitative analysis of drugs.

    Science.gov (United States)

    Pavlic, Marion; Libiseller, Kathrin; Oberacher, Herbert

    2006-09-01

    The potential of the combined use of ESI-QqTOF-MS and ESI-QqTOF-MS/MS with mass-spectral library search for the identification of therapeutic and illicit drugs has been evaluated. Reserpine was used for standardizing experimental conditions and for characterization of the performance of the applied mass spectrometric system. Experiments revealed that because of the mass accuracy, the stability of calibration, and the reproducibility of fragmentation, the QqTOF mass spectrometer is an appropriate platform for establishment of a tandem-mass-spectral library. Three-hundred and nineteen substances were used as reference samples to build the spectral library. For each reference compound, product-ion spectra were acquired at ten different collision-energy values between 5 eV and 50 eV. For identification of unknown compounds, a library search algorithm was developed. The closeness of matching between a measured product-ion spectrum and a spectrum stored in the library was characterized by a value called "match probability", which took into account the number of matched fragment ions, the number of fragment ions observed in the two spectra, and the sum of the intensity differences calculated for matching fragments. A large value for the match probability indicated a close match between the measured and the reference spectrum. A unique feature of the library search algorithm-an implemented spectral purification option-enables characterization of multi-contributor fragment-ion spectra. With the aid of this software feature, substances comprising only 1.0% of the total amount of binary mixtures were unequivocally assigned, in addition to the isobaric main contributors. The spectral library was successfully applied to the characterization of 39 forensic casework samples.

  6. Characterization of a PEGylated protein therapeutic by ion exchange chromatography with on-line detection by native ESI MS and MS/MS.

    Science.gov (United States)

    Muneeruddin, K; Bobst, C E; Frenkel, R; Houde, D; Turyan, I; Sosic, Z; Kaltashov, I A

    2017-01-16

    Detailed profiling of both enzymatic (e.g., glycosylation) and non-enzymatic (e.g., oxidation and deamidation) post-translational modifications (PTMs) is frequently required for the quality assessment of protein-based drugs. Challenging as it is, this task is further complicated for the so-called second-generation biopharmaceuticals, which also contain "designer PTMs" introduced to either enhance their pharmacokinetic profiles (e.g., PEGylated proteins) or endow them with therapeutic activity (e.g., protein-drug conjugates). Such modifications of protein covalent structure can dramatically increase structural heterogeneity, making the very notion of "molecular mass" meaningless, as ions representing different glycoforms of a PEGylated protein may have nearly identical distributions of ionic current as a function of m/z, making their contributions to the mass spectrum impossible to distinguish. In this work we demonstrate that a combination of ion exchange chromatography (IXC) with on-line detection by electrospray ionization mass spectrometry (ESI MS) and methods of ion manipulation in the gas phase (limited charge reduction and collision-induced dissociation) allows meaningful structural information to be obtained on a structurally heterogeneous sample of PEGylated interferon β-1a. IXC profiling of the protein sample gives rise to a convoluted chromatogram with several partially resolved peaks which can represent both deamidation and different glycosylation patterns within the protein, as well as varying extent of PEGylation. Thus, profiling the protein with on-line IXC/ESI/MS/MS allows it to be characterized by providing information on three different types of PTMs (designer, enzymatic and non-enzymatic) within a single protein therapeutic.

  7. Analysis of the constituents in jojoba wax used as a food additive by LC/MS/MS.

    Science.gov (United States)

    Tada, Atsuko; Jin, Zhe-Long; Sugimoto, Naoki; Sato, Kyoko; Yamazaki, Takeshi; Tanamoto, Kenichi

    2005-10-01

    Jojoba wax is a natural gum base used as a food additive in Japan, and is obtained from jojoba oil with a characteristically high melting point. Although the constituents of jojoba oil have been reported, the quality of jojoba wax used as a food additive has not yet been clarified. In order to evaluate its quality as a food additive and to obtain basic information useful for setting official standards, we investigated the constituents and their concentrations in jojoba wax. LC/MS analysis of the jojoba wax showed six peaks with [M+H]+ ions in the range from m/z 533.6 to 673.7 at intervals of m/z 28. After isolation of the components of the four main peaks by preparative LC/MS, the fatty acid and long chain alcohol moieties of the wax esters were analyzed by methanolysis and hydrolysis, followed by GC/MS. The results indicated that the main constituents in jojoba wax were various kinds of wax esters, namely eicosenyl octadecenoate (C20:1-C18:1) (1), eicosenyl eicosenoate (C20:1-C20:1) (II), docosenyl eicosenoate (C22:1-C20:1) (III), eicosenyl docosenoate (C20:1-C22:1) (IV) and tetracosenyl eiosenoate (C24:1-C20:1) (V). To confirm and quantify the wax esters in jojoba wax directly, LC/MS/MS analysis was performed. The product ions corresponding to the fatty acid moieties of the wax esters were observed, and by using the product ions derived from the protonated molecular ions of wax esters the fatty acid moieties were identified by MRM analysis. The concentrations of the wax esters I, II and III, in jojoba wax were 5.5, 21.4 and 37.8%, respectively. In summary, we clarified the main constituents of jojoba wax and quantified the molecular species of the wax esters without hydrolysis by monitoring their product ions, using a LC/MS/MS system.

  8. Analysis of neem oils by LC-MS and degradation kinetics of azadirachtin-A in a controlled environment. Characterization of degradation products by HPLC-MS-MS.

    Science.gov (United States)

    Barrek, Sami; Paisse, Olivier; Grenier-Loustalot, Marie-Florence

    2004-02-01

    Since it was first isolated, the oil extracted from seeds of neem (Azadirachtin indica A juss) has been extensively studied in terms of its efficacy as an insecticide. Several industrial formulations are produced as emulsifiable solutions containing a stated titer of the active ingredient azadirachtin-A (AZ-A). The work reported here is the characterization of a formulation of this insecticide marketed under the name of Neem-azal T/S and kinetic studies of the major active ingredient of this formulation. We initially performed liquid-liquid extraction to isolate the neem oil from other ingredients in the commercial mixture. This was followed by a purification using flash chromatography and semi-preparative chromatography, leading to (13)C NMR identification of structures such as azadirachtin-A, azadirachtin-B, and azadirachtin-H. The neem extract was also characterized by HPLC-MS using two ionization sources, APCI (atmospheric pressure chemical ionization) and ESI (electrospray ionization) in positive and negative ion modes of detection. This led to the identification of other compounds present in the extract-azadirachtin-D, azadirachtin-I, deacetylnimbin, deacetylsalannin, nimbin, and salannin. The comparative study of data gathered by use of the two ionization sources is discussed and shows that the ESI source enables the largest number of structures to be identified. In a second part, kinetic changes in the main product (AZ-A) were studied under precise conditions of pH (2, 4, 6, and 8), temperature (40 to 70 degrees C), and light (UV, dark room and in daylight). This enabled us to determine the degradation kinetics of the product (AZ-A) over time. The activation energy of the molecule (75+/-9 kJ mol(-1)) was determined by examining thermal stability in the range 40 to 70 degrees C. The degradation products of this compound were identified by use of HPLC-MS and HPLC-MS-MS. The results enabled proposal of a chemical degradation reaction route for AZ-A under

  9. PyMS: a Python toolkit for processing of gas chromatography-mass spectrometry (GC-MS data. Application and comparative study of selected tools

    Directory of Open Access Journals (Sweden)

    O'Callaghan Sean

    2012-05-01

    Full Text Available Abstract Background Gas chromatography–mass spectrometry (GC-MS is a technique frequently used in targeted and non-targeted measurements of metabolites. Most existing software tools for processing of raw instrument GC-MS data tightly integrate data processing methods with graphical user interface facilitating interactive data processing. While interactive processing remains critically important in GC-MS applications, high-throughput studies increasingly dictate the need for command line tools, suitable for scripting of high-throughput, customized processing pipelines. Results PyMS comprises a library of functions for processing of instrument GC-MS data developed in Python. PyMS currently provides a complete set of GC-MS processing functions, including reading of standard data formats (ANDI- MS/NetCDF and JCAMP-DX, noise smoothing, baseline correction, peak detection, peak deconvolution, peak integration, and peak alignment by dynamic programming. A novel common ion single quantitation algorithm allows automated, accurate quantitation of GC-MS electron impact (EI fragmentation spectra when a large number of experiments are being analyzed. PyMS implements parallel processing for by-row and by-column data processing tasks based on Message Passing Interface (MPI, allowing processing to scale on multiple CPUs in distributed computing environments. A set of specifically designed experiments was performed in-house and used to comparatively evaluate the performance of PyMS and three widely used software packages for GC-MS data processing (AMDIS, AnalyzerPro, and XCMS. Conclusions PyMS is a novel software package for the processing of raw GC-MS data, particularly suitable for scripting of customized processing pipelines and for data processing in batch mode. PyMS provides limited graphical capabilities and can be used both for routine data processing and interactive/exploratory data analysis. In real-life GC-MS data processing scenarios PyMS performs

  10. Determination of 25-OCH3-PPD and the related substances by UPLC-MS/MS and their cytotoxic activity.

    Science.gov (United States)

    Ding, Meng; Lu, Jingjing; Zhao, Chen; Zhang, Sainan; Zhao, Yuqing

    2016-06-01

    20(R)-25-methoxyl-dammarane-3β,12β,20-triol (25-OCH3-PPD) is a promising antitumor compound belonging to triterpenoid saponins isolated from radix notoginseng. A systematic research on the related impurities in raw material of 25-OCH3-PPD has not been conducted. In this study, three impurities obtained by HPLC-ELSD and characterized by (13)C NMR and MS were observed in the raw material of 25-OCH3-PPD. Cytotoxic activities of the related substances were also evaluated, of which impurity B with 25-OCH3-PPD showed synergistic inhibitory activity against BGC-823 with IC50 values of 8.33μM. Furthermore, a rapid and selective UPLC-MS/MS method was developed for simultaneous determination of the principal component and three related substances in the raw material of 25-OCH3-PPD. Multiple reaction monitoring scan mode was used for the quantification of 20(R)-25-OCH3-PPD and its three related substances. The four constituents were separated within 11min on a BEH C18 column (100 mm×2.1mm, 1.7μm) using a mobile phase comprising methanol and 0.03% formic acid water (82:18, v/v) at a flow rate of 0.2mL/min. The proposed UPLC-MS/MS method displayed acceptable levels of linearity, precision, repeatability, and accuracy. In addition, the proposed method was successfully applied for the establishment of a rational quality control standard for the raw material of 25-OCH3-PPD. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Determining the degradation efficiency and mechanisms of ethyl violet using HPLC-PDA-ESI-MS and GC-MS

    Directory of Open Access Journals (Sweden)

    Chung Wen-Hsin

    2012-06-01

    Full Text Available Abstract Background The discharge of wastewater that contains high concentrations of reactive dyes is a well-known problem associated with dyestuff activities. In recent years, semiconductor photocatalysis has become more and more attractive and important since it has a great potential to contribute to such environmental problems. One of the most important aspects of environmental photocatalysis is in the selection of semiconductor materials like ZnO and TiO2, which are close to being two of the ideal photocatalysts in several respects. For example, they are relatively inexpensive, and they provide photo-generated holes with high oxidizing power due to their wide band gap energy. In this work, nanostructural ZnO film on the Zn foil of the Alkaline-Manganese Dioxide-Zinc Cell was fabricated to degrade EV dye. The major innovation of this paper is to obtain the degradation mechanism of ethyl violet dyes resulting from the HPLC-PDA-ESI-MS analyses. Results The fabrication of ZnO nanostructures on zinc foils with a simple solution-based corrosion strategy and the synthesis, characterization, application, and implication of Zn would be reported in this study. Other objectives of this research are to identify the reaction intermediates and to understand the detailed degradation mechanism of EV dye, as model compound of triphenylmethane dye, with active Zn metal, by HPLC-ESI-MS and GC-MS. Conclusions ZnO nanostructure/Zn-foils had an excellent potential for future applications on the photocatalytic degradation of the organic dye in the environmental remediation. The intermediates of the degradation process were separated and characterized by the HPLC-PDA-ESI-MS and GC-MS, and twenty-six intermediates were characterized in this study. Based on the variation of the amount of intermediates, possible degradation pathways for the decolorization of dyes are also proposed and discussed.

  12. Natalizumab Discontinuation and Treatment Strategies in Patients with Multiple Sclerosis (MS): A Retrospective Study from Two Italian MS Centers.

    Science.gov (United States)

    Lo Re, Marianna; Capobianco, Marco; Ragonese, Paolo; Realmuto, Sabrina; Malucchi, Simona; Berchialla, Paola; Salemi, Giuseppe; Bertolotto, Antonio

    2015-12-01

    Natalizumab (NTZ) discontinuation can be followed by multiple sclerosis (MS) disease reactivation. Currently no disease-modifying drug (DMD) has been shown to be able to abolish disease reactivation. The aims of the current study were: (1) to determine the frequency of MS reactivation after NTZ discontinuation; (2) to evaluate predictors of reactivation risk, and (3) to compare the effect of different treatments in reducing this risk. Data from 132 patients with MS followed-up for 2 years before NTZ treatment and 1 year after interruption were collected from two Italian MS centers and retrospectively evaluated. Overall, 72 of 132 patients (54.5%) had relapses after NTZ discontinuation and 60 of 125 patients (48%), who had magnetic resonance imaging, had radiological reactivation. Rebound was observed in 28 of 132 patients (21.2%). A higher number of relapses in the 2 years before NTZ treatment, a longer washout period, and a lower number NTZ infusions correlated with reactivation and rebound. Untreated patients (n = 37) had higher clinical and radiological activity and rebound in comparison to patients receiving DMDs. Moreover, a lower risk of relapses was found in patients treated with second-line therapies (NTZ and fingolimod) than in those treated with first-line therapies (interferon beta, glatiramer acetate, teriflunomide, azathioprine). Interestingly, no disease reactivation in off-label treatment (rituximab, autologous hematopoietic stem cell transplantation) was observed. NTZ discontinuation is a risk for MS reactivation and rebound. An alternative treatment should be promptly resumed mainly in patients with a previous very active disease course and with a shorter NTZ therapy. Second-line therapies demonstrate superiority in preventing relapses after NTZ discontinuation.

  13. High temperature liquid chromatography hyphenated with ESI-MS and ICP-MS detection for the structural characterization and quantification of halogen containing drug metabolites

    International Nuclear Information System (INIS)

    Vlieger, Jon S.B. de; Giezen, Mark J.N.; Falck, David; Tump, Cornelis; Heuveln, Fred van; Giera, Martin; Kool, Jeroen; Lingeman, Henk; Wieling, Jaap; Honing, Maarten; Irth, Hubertus; Niessen, Wilfried M.A.

    2011-01-01

    Highlights: → Hyphenation of high temperature liquid chromatography to ICP-MS and ESI-MS. → Structural characterization of kinase inhibitor metabolites with high resolution MS n experiments. → Quantification of drug metabolites with ICP-MS based on Iodine detection. → Significant changes in ESI-MS response after small structural changes. - Abstract: In this paper we describe the hyphenation of high temperature liquid chromatography with ICP-MS and ESI-MS for the characterization of halogen containing drug metabolites. The use of temperature gradients up to 200 deg. C enabled the separation of metabolites with low organic modifier content. This specific property allowed the use of detection methods that suffer from (significant) changes in analyte response factors as a function of the organic modifier content such as ICP-MS. Metabolites of two kinase inhibitors (SB-203580-Iodo and MAPK inhibitor VIII) produced by bacterial cytochrome P450 BM3 mutants and human liver microsomes were identified based on high resolution MS n data. Quantification was done using their normalized and elemental specific response in the ICP-MS. The importance of these kinds of quantification strategies is stressed by the observation that the difference of the position of one oxygen atom in a structure can greatly affect its response in ESI-MS and UV detection.

  14. Development and Validation of a Novel LC-MS/MS Opioid Confirmation Assay: Evaluation of β-glucuronidase Enzymes and Sample Cleanup Methods.

    Science.gov (United States)

    Yang, He S; Wu, Alan H B; Lynch, Kara L

    2016-06-01

    With the rise in the use and misuse of prescription opioids, there is an increasing need for the confirmed identification of opioid analgesics in toxicology laboratories. The goals of this study were to (i) systematically evaluate the hydrolysis efficiency of four β-glucuronidase enzymes under optimized condition; (ii) evaluate compound recovery, matrix effects and precision of three protein precipitation plates and (iii) develop and validate a qualitative liquid-chromatography mass spectrometry (LC-MS/MS) assay to identify 13 opioids in urine. A recombinant β-glucuronidase exhibited the best overall hydrolysis efficiency for seven opioid glucuronide conjugates compared with β-glucuronidase from red abalone, Escherichia coli and Patella vulgata One of the protein precipitation plates tested exhibited overall better recovery of the opioids and lower ion suppression compared with the other two plates. An ESI positive mode LC-MS/MS assay for qualitative opioid analysis was developed and validated. Linearity, LOD, precision, matrix effect, recovery, carryover and interference of the method were evaluated. Sixty-two patient samples were analyzed by both a legacy GC-MS opioid method and the LC-MS/MS method, and 22 samples were analyzed by the LC-MS/MS and an LC-MS/MS reference method. The results of the comparisons showed good concordance. Overall, we described an efficient sample preparation procedure for a sensitive qualitative opioid confirmation assay in urine. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Comprehensive comparison of in silico MS/MS fragmentation tools of the CASMI contest: database boosting is needed to achieve 93% accuracy.

    Science.gov (United States)

    Blaženović, Ivana; Kind, Tobias; Torbašinović, Hrvoje; Obrenović, Slobodan; Mehta, Sajjan S; Tsugawa, Hiroshi; Wermuth, Tobias; Schauer, Nicolas; Jahn, Martina; Biedendieck, Rebekka; Jahn, Dieter; Fiehn, Oliver

    2017-05-25

    In mass spectrometry-based untargeted metabolomics, rarely more than 30% of the compounds are identified. Without the true identity of these molecules it is impossible to draw conclusions about the biological mechanisms, pathway relationships and provenance of compounds. The only way at present to address this discrepancy is to use in silico fragmentation software to identify unknown compounds by comparing and ranking theoretical MS/MS fragmentations from target structures to experimental tandem mass spectra (MS/MS). We compared the performance of four publicly available in silico fragmentation algorithms (MetFragCL, CFM-ID, MAGMa+ and MS-FINDER) that participated in the 2016 CASMI challenge. We found that optimizing the use of metadata, weighting factors and the manner of combining different tools eventually defined the ultimate outcomes of each method. We comprehensively analysed how outcomes of different tools could be combined and reached a final success rate of 93% for the training data, and 87% for the challenge data, using a combination of MAGMa+, CFM-ID and compound importance information along with MS/MS matching. Matching MS/MS spectra against the MS/MS libraries without using any in silico tool yielded 60% correct hits, showing that the use of in silico methods is still important.

  16. Amino acid analysis in physiological samples by GC-MS with propyl chloroformate derivatization and iTRAQ-LC-MS/MS.

    Science.gov (United States)

    Dettmer, Katja; Stevens, Axel P; Fagerer, Stephan R; Kaspar, Hannelore; Oefner, Peter J

    2012-01-01

    Two mass spectrometry-based methods for the quantitative analysis of free amino acids are described. The first method uses propyl chloroformate/propanol derivatization and gas chromatography-quadrupole mass spectrometry (GC-qMS) analysis in single-ion monitoring mode. Derivatization is carried out directly in aqueous samples, thereby allowing automation of the entire procedure, including addition of reagents, extraction, and injection into the GC-MS. The method delivers the quantification of 26 amino acids. The isobaric tagging for relative and absolute quantification (iTRAQ) method employs the labeling of amino acids with isobaric iTRAQ tags. The tags contain two different cleavable reporter ions, one for the sample and one for the standard, which are detected by fragmentation in a tandem mass spectrometer. Reversed-phase liquid chromatography of the labeled amino acids is performed prior to mass spectrometric analysis to separate isobaric amino acids. The commercial iTRAQ kit allows for the analysis of 42 physiological amino acids with a respective isotope-labeled standard for each of these 42 amino acids.

  17. Quality control of Al alloy by ICP-MS

    International Nuclear Information System (INIS)

    Zahran, N.F.; Amr, M.A.; Helal, A.I.; Waly, S.A.; Afifi, Y.K.

    2000-01-01

    Laser ablation sample introduction system in combination with an inductive coupled plasma mass spectrometer (ICP-MS) is used for the investigation of elemental distribution of Al alloy. The samples are ablated by an ultraviolet laser beam at 266 nm with an energy of 4mJ/shot at a repetition rate of 20 Hz. Samples are digested using HNO 3 in a microwave system and analyzed in a solution form by ICP-MS. The quantification of the analytical results is carried out using multielement solution. Quantitative data from the solution samples are used as a standard data for the laser ablation technique. The effect of Aluminum as a matrix is studied. High-resolution mass spectrometer is used to identify the Aluminum polyatomic ions in the ICP-ion source

  18. MRI criteria for MS in patients with clinically isolated syndromes

    DEFF Research Database (Denmark)

    Montalban, X.; Tintore, M.; Swanton, J.

    2010-01-01

    neurologists and neuroradiologists. In some circumstances, several MRI examinations are needed to achieve an accurate and prompt diagnosis. This provides an incentive for continued efforts to refine the incorporation of MRI-derived information into the diagnostic workup of patients presenting with a clinically...... isolated syndrome. Within the European multicenter collaborative research network that studies MRI in MS (MAGNIMS), a workshop was held in London in November 2007 to review information that may simplify the existing MS diagnostic criteria, while maintaining a high specificity that is essential to minimize...... false positive diagnoses. New data that are now published were reviewed and discussed and together with a new proposal are integrated in this position paper. Neurology(R) 2010;74:427-434...

  19. Sterol Profile for Natural Juices Authentification by GC-MS

    Science.gov (United States)

    Culea, M.

    2007-04-01

    A GC-MS analytical method is described for some natural juices analysis. The fingerprint of sterols was used to characterize the natural juice. A rapid liquid-liquid extraction method was used. The sterols were separated on a Rtx-5MS capillary column, 15m×0.25mm, 0.25μm film thickness, in a temperature program from 50°C for 1 min, then ramped at 15°C/min to 300°C and held for 15 min. Identification of sterols and their patterns were used for juice characterization. The sterol profile is a useful approach for confirming the presence of juices of orange, grapefruit, pineapple and passion fruit in compounded beverages and for detecting of adulteration of fruit juices.

  20. LC-MS at core of university-industry link

    DEFF Research Database (Denmark)

    Linding, Rune

    2013-01-01

    , and the Orbitrap Fusion Tribrid system is designed for precisely this type of visionary research.’’ DTU is establishing the state-of-the-art laboratory to develop new experiments to dig deeper into the core machinery of the cell. The new laboratory will use four TFS Q Exactive LC-MS/MS systems, and nano-LC 1000.......’’ ‘‘We are immensely pleased to be working with this talented and motivated team of scientists,’’ said Iain Mylchreest, vice president, research and development, life science mass spectrometry, TFS. ‘‘We share with them the objective of pushing the limits of science to make the world a better place...