Identifikasjon av ukjente legemidler og misbruksstoffer ved spektersøk på GCMS ved bruk av deconvolution software

Hensikt og problemstilling: Gasskromatografi-massespektrometri (GCMS) brukes ofte i laboratorier som utfører toksikologisk screening etter legemidler, giftstoffer og misbruksstoffer i biologiske prøver. Det kan imidlertid være en stor utfordring å identifisere ukjente stoffer i prøver med komplekse matrikser og ko-eluerende interferenser. Spesielt er dette et problem for detektering av stoffer i lave konsentrasjonsområder. Deconvolution-teknikk (DRS - Deconvolutiuon Reporting Software) ”løser opp" og ekstraherer spektra fra overlappende interfererende topper. Deretter sammenlignes ekstraherte spektra mot et referanse spekterbibliotek. I denne oppgaven undersøkes effekten av DRS og bruken av et retensjonstidslåst (RTL) bibliotek (FT-DBL – Forensic Toxicology Database Library). I tillegg sammenliknes bruk av en 15m DB-5 kolonne med en 30m HP-5 kolonne. Tre problemstillinger ønskes besvart i denne oppgaven: 1. Vil en metode med deconvolution-teknikk og FT-DBL-RTL på en 15 m DB5 kolonne (ny metode) gi flere funn sammenlignet med en metode uten deconvolution-teknikk på en 30 m HP5- kolonne (gammel metode)? 2. Vil antall funn ved bruk av de to forskjellige kolonnene påvirkes av hvorvidt deconvolution-teknikk benyttes eller ikke? 3. Vil ny metode gi en gevinst med tanke på ressursbruk i forhold til gammel metode? Metode/eksperimentelt: 167 blodprøver fra rettsmedisinske obduksjoner ble ekstrahert, injisert og rapportert på to GCMS-instrument som var identiske med unntak av de faktorene som omfattes av undersøkelsens problemstilling. Resultater/Konklusjon: 1. Ved bruk av metode med deconvolution, FT-DBL-RTL og 15 m DB5- kolonne (ny metode) ble det registrert 40 % flere funn enn ved bruk av metode uten deconvolution på en 30 m HP5- kolonne (gammel metode). 2. Ved bruk av metode med deconvolution både på 15 m DB5- og på 30 m HP5-kolonne, ble det registrert 18 % flere funn med 15 m DB5-kolonne sammenlignet med 30 m HP5- kolonne. Ved bruk av metode uten deconvolution på 15 m DB5- og på 30 m HP5-kolonne, ble det ikke funnet forskjell i antall registrerte analytter. 3. Ved ny metode med deconvolution, FT-DBL-RTL og 15 meters DB5-kolonne ble kjøretid på instrumentet nesten halvert, og den totale analysetiden (instrumenttid og rapportering) ble redusert med 60 % i forhold til gammel metode uten deconvolution og 30 m HP5-kolonne

Recurrent malignant ventricular arrhythmias and paresthesia—a mystery revealed as aconitine poisoning: a case report

Abstract Background We report a case of a clinical challenge lasting for 12 months, with severe and unresolved clinical features involving several medical disciplines. Case presentation A 53-year-old Caucasian male, who had been previously healthy apart from a moderate renal impairment, was hospitalized 12 times during a 1-year period for a recurrent complex of neurological, cardiovascular, and gastrointestinal symptoms and signs, without any apparent etiology. On two occasions, he suffered a cardiac arrest and was successfully resuscitated. Following the first cardiac arrest, a cardiac defibrillator was inserted. During the 12th admission to our hospital, aconitine poisoning was suspected after a comprehensive multidisciplinary evaluation and confirmed by serum and urine analyses. Later, aconitine was also detected in a hair segment, indicating exposure within the symptomatic period. After the diagnosis was made, no further episodes occurred. His cardiac defibrillator was later removed, and he returned to work. A former diagnosis of epilepsy was also abandoned. Criminal intent was suspected, and his wife was sentenced to 11 years in prison for attempted murder. To make standardized assessments of the probability for aconitine poisoning as the cause of the eleven prior admissions, an “aconitine score” was established. The score is based on neurological, cardiovascular, gastrointestinal, and other clinical features reported in the literature. We also make a case for the use of hair analysis to confirm suspected poisoning cases evaluated after the resolution of clinical features. Conclusion This report illustrates the medical challenge raised by cases of covert poisoning. In patients presenting with symptoms and signs from several organ systems without apparent cause, poisoning should always be suspected. To solve such cases, insight into the effects of specific toxic agents is needed. We present an “aconitine score” that may be useful in cases of suspected aconitine poisoning

Relevant genes examined in brown adipose tissue (BAT) in the chronic study.

<p>Data are given as fold change relative to vehicle, and presented as mean±SEM. Data shown are normalised to P0 (<i>Arbp</i>), with comparable results when normalised to <i>β-actin</i>.</p>*<p>P≤0.05 vs vehicle.</p>**<p>P≤0.01 vs vehicle.</p>***<p>P≤0.001 vs vehicle.</p

Serum levels of antipsychotic agents.

<p>Fasting serum levels of antipsychotic agents, given in nM, after 2 or 8 weeks of treatment, respectively.</p

Parameters measured during the subchronic experiment.

<p>a) daily food intake, b) daily cumulative weight gain, and c) and serum levels of total cholesterol, triglycerides, liver total cholesterol and triglycerides at the 2-week end point of the subchornic experiment. VEH, vehicle, TTA: tetradecylthioacetic acid, OLZ: olanzapine. * P≤0.05 vs vehicle.</p

Selected genes with drug exposure-related, differential expression in liver in the subchronic experiment.

<p>Data are given as fold change relative to vehicle, and presented as mean±SEM. Data shown are normalised to P0 (Arbp), with comparable results when normalised to β-actin.</p>*<p>P≤0.05 vs vehicle.</p>**<p>P≤0.01 vs vehicle.</p>***<p>P≤0.001 vs vehicle. Subchronic data for the VEH, OLZ, and APZ groups have been reported in a previous article <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0050853#pone.0050853-Skrede1" target="_blank">[23]</a>. Gene abbreviations: <i>Scd1</i>; stearoyl-CoA desaturase. <i>Fasn</i>; fatty acid synthase. <i>Srebp1</i>; sterol regulatory element binding protein 1, <i>Srebp2</i>; sterol regulatory element binding protein 2. <i>Hmgcr</i>; 3-hydroxy-3-methylglutaryl-CoA reductase. <i>Ppara</i>: peroxisome proliferator activated receptor α, <i>Pparg</i>: peroxisome proliferator activated receptor γ. <i>Cpt2</i>: carnitine O-palmitoyltransferase 2. <i>Acox1</i>: acyl-Coenzyme A oxidase 1.</p

Fasting lipids in serum and liver at 8 weeks.

<p>Serum and liver lipids after chronic treatment with vehicle (VEH), olanzapine (OLZ), clozapine (CLZ), tetradecylthioacetic acid (TTA), or a combination of OLZ/CLZ+TTA. * P≤0.05, ** P≤0.01, *** P≤0.001.</p

Relevant genes examined in brown adipose tissue (BAT) in the subchronic study.

<p>Data are given as fold change relative to vehicle, and presented as mean±SEM. Data shown are normalised to P0 (<i>Arbp</i>), with comparable results when normalised to <i>β-actin</i>.</p>*<p>P≤0.05 vs vehicle.</p>**<p>P≤0.01 vs vehicle.</p>***<p>P≤0.001 vs vehicle.</p

Daily food intake during 8 weeks of treatment with antipsychotics and TTA.

<p>Total food intake during the entire treatment period of 8 weeks (a) and daily food intake during chronic treatment with vehicle (open circles), antipsychotic monotherapy, TTA, or antipsychotics in combination with TTA (filled circles; b-f). Data are given as mean±SEM. * P≤0.05 vs vehicle (Dunnett’s post hoc test for daily food intake). TTA: tetradecylthioacetic acid, OLZ: olanzapine, CLZ: clozapine.</p